The main reason that the patient has come to the office.
A mother brings in her 4 year old son. The mother says he has a lazy eye. What do you need to find out?
What does she mean by “lazy eye”.
A patient with heart problems?
May have hardening of the arteries in the eye. (Ocular disorders associated with heart problems include hardening of the arteries and/or blood vessel blockage)
Knowledge of a patient’s breathing or lung problems would be important if the patient also has?
Glaucoma (Certain glaucoma meds are contraindicated in patients with lung disease)
Your patient states that he has rheumatoid arthritis. You should now ask symptom-related questions to find out if he has?
Dry eye (Dry eye is strongly associated with rheumatoid arthritis)
Major infections that can affect the eye include?
Human immunodeficiency virus (HIV), gonorrhea, tuberculosis, and herpes simplex.
A patient taking a diuretic probably has which health problem?
Heart trouble (Heart patients are placed on diuretics to reduce excess fluid in the body, thereby reducing heart strain)
High blood pressure is frequently treated by?
It is important to know if a patient is taking birth control pills because?
These hormones can cause changes in the retina. (Includes retinal artery and vein occlusion)
A patient who has been taking oral steroids for long periods should be evaluated for possible development of?
An example of an analgesic is?
A male patient is going to be scheduled for cataract surgery. What is one medication that is of concern?
Slidenafil Citrate (Viagra) (Medications for erectile dysfunction have been implicated in intraoperative floppy iris syndrome (a common complication of cataract surgery))
The most common ocular disorders that run in families are?
Strabismus, myopia and glaucoma
What are 3 potentially a hereditary disorders?
Keratoconus, migraine headaches and nystagmus are usually hereditary
Any pupil larger than what size is considered mydriatic?
True or false: older people tend to have smaller pupils?
Unequal pupil size is termed?
Helps with the diagnosis, management and non-surgical treatment of eye muscles
Measures and fits patients with artificial eyes
Clear, round membrane at the front of the globe
Colored circle of tissue that is behind the cornea
Where light enters the eye; controlled by the iris by enlarging or reducing the size
Immediately behind iris; this is the second part of the optical focusing system
A clear, jelly-like substance that fills the large space behind the lens
Where light produces an image at the back surface of the eye
Light sensitive cells of the retina convert the image to electrical impulses that are carried to the brain
The range from front to back – normal is about 23-25 mm and width is about 24mm
Corneal central thickness (CCT)
About 545 micrometers or just over 0.5 mm
Measuring the corneal thickness either optically or with ultrasound; important in the evaluation of glaucoma
Average for cornea – 42 diopters; average for lens – 18 diopters; total eye – 60 diopters
Tissues and structures surrounding the eye; include the orbit, extra ocular muscles, eyelids and lacrimal apparatus
Bony cavity in the skull that holds the globe; contains 7 bones,extra ocular muscles, blood vessels and nerves
A fracture in the floor of the orbit that results from blunt force trauma
Extra ocular muscles
Muscles that control the movement of the globe
Rotates the eye inward toward the nose; called adduction
Rotates the eye outward toward the temple; called abduction
Causes torsional movement and twists the eye down and inward; called incylotorsion
Causes torsional movement and twists the eye up and outward; called exclotorsion
Turns the eye upward secondarily incylotorsion
Turns the eye downward secondarily exclyclotorsion
Almond shaped opening between the upper and lower lids
The point where lids meet on nasal side of palpebral fissure
The temporal junction of the lids
Abnormal growth of an eyelash in the wrong direction
Stye (External Hordeolom)
When lash follicle becomes inflamed causing a red sore bump near the outer edge of the lid
On posterior of the eyelid, row of tiny holes that are the opening of oil secreting glands
When a meibomian gland becomes inflamed and infected, producing swelling
A lump on the outer lid cause by an internal hordeolum
Common inflammation that produces red and crusted lid margins
Gives eyelids firmness and shape; within middle layer of both eyelids
Middle layer; circular muscle that close the eye when contracted
Attached to upper tarsal plate; when contracts raises the upper lid
When the Levator muscle loses its ability to contract and causes a “droopy” eyelid
When the lower lid falls or pulls away from the eye due to malformation of tissues or damage
When the upper and lower lids turn inward
Thin translucent mucous membrane that lines the inner surface of the lids and outer surface of the globe
Portion of the tissue lining the eyelids
Portion of the tissue covering the outer globe
Area where palpebral and bulbar portions meet beneath upper and lower lids and is a loose pocket of conjunctiva tissue
Consists of orbital structure that produce tears and the ducts that drain excess fluid from the front of the eye into the nose
Contains an outer oily substance secreted by the meibomian glands and a middle aqueous layer that provides moisture, oxygen and nutrients
Lateral part of upper lid and has an inner layer composed of mucinous (sticky) fluid
Upper and lower canaliculus
“Tubes” that begin at the punci and lead to the lacrimal sac
Where the lacrimal sac empties into the nasal cavity
Schirmer and phenol red thread test
Tests that detect dry eyes
Inflammation of the lacrimal sac due to a blockage in the nasolacrimal duct and causes constant tearing
What type of medication is frequently used to treat pain?
What 2 types of medication is frequently used to treat inflamation?
NSAIDS and Steroids
Condition in which 2 eyes have unequal refracting power
Marked variation in the chromaticity, the color density of Red blood cells
Condition that results from an excessive difference in prescription between the eyes causing a difference in image size perceived between the eyes from unequal magnification
An iris coloboma usually causes a pupillary shape defect where?
A 6 o’clock (Iris coloboma is a congential defect where the iris fails to fuse, usually inferiorly or at 6 o’clock)
To evaulate a patient for tonic pupil (or Adies’ tonic pupil) one would use which method?
Accommodation response test (In Adie’s tonic pupil, there is a rapid/normal reaction of constriction when looking at a near object, the pupil is also slow in its reaction to light)
Testing that reveals normal – appearing pupils that react appropriatley is documented by the acronym?
PERRLA (Pupils Equally Round and Reactive to Light and Accomodation)
The most common cause of a false positive pupillary defect is?
Weak flashlight Batteries
Each of the following disorders can cause a change in pupil size except?
Open angle Glaucoma (Iritis, angle-closure glaucoma attack and drug reactions can all cause a change in pupil size)
Argyll Robertson pupils are often?
Unreactive to direct or consensual light
Argyll Robertson pupils
Bilateral small pupils that reduce in size when the patient focuses on a near object, but do not constrict when exposed to bright light
You discover your patient has an Argyll Robertson pupil, this pupillary defect is associated with?
Which is associated with ptosis, miosis, and lack of perspiration on the affected side?
Horner’s syndrome is caused by?
Adie’s tonic pupil (or tonic pupil) is caused by?
Nerve damage (damage to the short posterior ciliary nerves is the cause of Adie’s tonic pupil)
You might first suspect that the patient has a tonic pupil when?
The response to direct light is slow (A tonic pupil will have a slow reaction to direct light. A pupil that enlarges in direct light most likely has a Marcus Gunn or RAPD defect, horners syndrome exhibits ptosis on that same side)
Soft contact lens diameter can be selected by measuring the patients?
Visible iris diameter (A soft contact lens should extend beyond the limbus, so one needs to measure the visible iris diameter (limbus-to-limbus))
Your patient is going to be fit with rigid gas permeables (RPGs). In addition to the usual parameters, you should also measure?
Palpebral fissures (distance between upper and lower lid)
Before inserting a soft lens, the patient should make sure it is not inverted. This can by done by?
Visual inspection or the taco test
To insert a soft lens?
The lens should be wet and the finger dry
The patient should be instructed to place a contact lens?
Directly on the cornea
Use of lotion or moisturizer before handling lenses or use of makeup, hairspray or face cream after inserting lens can cause?
Rigid contact lenses are often removed by blinking them out. For this technique to work?
The lens must be centered on the eye
Which technique should NOT be used to remove a rigid lens while using a plunger?
Run the plunger over the cornea and sclera to locate a “loss lens”
Soft lenses should be cleaned immediatly after removal because?
Grunge is easier to remove at body temperature (A soft lens should never be allowed to dry out)
When using a one-step contact lens solution, what should one do upon removing a lens from the eye?
Place the lens in the palm, add solution and gently rub with fingertip
When not bieng worn, even rigid lens should be stored in soaking solution because?
It prevents warping
If a gas-permeable lens dries out?
It should be soaked for at least 4 hours (If a gas-permeable lens dries-out, the base curve may change. It should return to normal after soaking for 4 hours or overnight)
Wetting solutions are used to?
Enable tears to spread evenly on the lens surface (Wetting solutions do not sterilize, reduce deposits or prevent scratches)
What is the least sterile rewetting fluid?
Salvia (Urine is more sterile then saliza and tap and pool water (although “cleaner”) can cause a lens to adhere to the cornea and cause corneal edema)
Every patient who wears extended-wear contact lenses should be told to?
Use lubricating drops every morning and during the day
True or False: Contact lens cases should be washed weekly with hot water and soap?
False (Soap can leave a residue and the case should be replaced every couple of months)
Giant papillary Conjuntivitis is suspected to be?
An allergic response (An allergic response of the body to the protein deposits on a contact lens (usually soft), as the deposits break down, an allergice response is triggered)
True or false: Soft contact lenses provide crisper vision then rigid lenses?
False (As a rule, soft lenses (being very flexable) do not provide the crisp, sharp vision of rigid lenses)
One of the main disadvantages of soft lenses is?
Poor durability (Because it is soft, it makes it vulnerable to durability and can be torn eaily. However there is less lens loss, better oxygen permeability and lower risk on insertion)
The characteristic of soft lens matierial that is responsible for most of the lens advantages (and disadvantages) is its?
Ability to absorb water (Soft lens is hyrophilic (loves water). The fact that it absorbs water is responsible for its entire nature which includes comfort, flexability and oxygen transmission. There is however very little tear exhange (as opposed to rigid lenses) but they are not resistant to deposits)
All of the following are poor candidates for extended-wear lenses except?
Those taking blood thinners (Those who work in dusty environments, those with chronic Blepheritis and those with pre-exhisting giant papillary conjuntivitis are poor condidates)
The lower the water content of a soft lens?
The more durable the lens (The lower the water content, the more rigid it is and therefore more durable, although a lower water content is less oxygen transmissible)
Selecting the power of a spherical soft contact lens is based on?
The spherical equivalent of the refractometric measurment (The power of a sperical equivalent of the refrometric measurement. The K reading are not used for calculating the power)
To obtain the spherical equivalent?
Add half the cylinder to the sphere algebraically, deleting the cylinder and axis
The amount of astigmatism that is present after the patient is fitted with lenses is referred to as?
The most common source of residual astigmatism in contact lens wearers is?
The crystalline lens (Residual astigmatism is most often caused by lenticular astigmatism or irregular curvature of the lens (this does not show up on K readings))
Polymethylmethacrylate or PMMA
The orignal hard lens
Hydroxymethylmethacrylate or HEMA
Cellulose acetate butyrate or CAB
Gas-permeable hard lens
The major difficulty with fitting toric lenses is?
Lens stability on the eye (Keeping the cylinder properly aligned means keeping the lens aligned. A Spherical lens is normally pushed around and rotates during blinking. This spells disacter for a toric lens fit)
True or False: A patient with Exophthalmos would make a patient a poor candidate for gas-permeable contact lenses?
True (An exophtalmic (bulging eye) usually is afit better with a soft lens, which is more stable on the eye and does not interfere with the lids)
The fact that gas-permeable contact lens material allows more oxygen on the eye means that?
The lens can be larger than a PMMA lens (Becuase a gas-permeable contact lens allows more oxygen to get to the cornea, the eye can tolerate a larger lens. A properly fit gas-permeable lens does not sit of the lower lid)
The average life of a rigid-gas-permeable lens is?
Over refractometry of a contact lens is useful in fine tuning?
What are 4 routine uses of a bandage contact lenses?
A plano lens is usually used due to it being thinner and therefore higher oxygen-permeability. They are routinely used for promotting healing and protection, patient comfort and as a drug reservoir
The key in selecting a bandage contact lens is?
Oxygen permeability (Patient DO NOT usually handle bandage contact lenses)
Even if a patient has a hyperopic refractive error, it is best to try a plano bandage lens first because?
A plano lens is thinner
True or False: Storing a direct ophthalmoscope with the lens setting on zero will help prevent dust build-up on the lenses?
True (With the setting on zero, there are no exposed lenses in the instruments aperture)
Unless the maufactures instructions indicated otherwise, the perimeter bowl surface may be cleaned with?
A mild detergent and water
When brushing or wiping the perimeter bowl surface, it is important to avoid?
excessive pressure/friction (Putting too much pressure on an area inside the bowl might change the reflective properties of the bowl in that area or scratch the finish)
Dirty tangent screen test objects should be cleaned with?
Soap and water
The tangent screen itself can be cleaned?
By gently whisking with a very soft brush
Unless the maufacturers instruction state otherwise, a glass lens (non-bloomed) may be cleaned by any of the following except?
Commercial chrome cleaner (Blooming refers to a special coating on the lens)
Do no use commercial glass cleaner on plastic lenses because?
This can cloud the lens
What will remove the coating on a bloomed lens (Such as the indirect ophthalmoscope lens)?
Heavily rubbing the lens to remove fingerprints (Friction can remove the coating on a bloomed lens, be gentle)
The best way to remove dust from a funus camera lens is to first?
Blow off dust with air (The order of cleaning for a camera lens is blow using a bulb syringe (not your breath), brush and wipe)
Which surface of an ophthalmodynamometer might require disinfection?
The tip (The tip touches the eye and therefore must be disinfected after every us)
True or False: Front surface mirrors produce a faint double image of reflection?
False (They DO NOT produce a double image which is why they are used in optical situations)
Prior to cleaning a front surface mirror, one should?
Use canned air to remove loose dust
A mirror surface should be dried by?
Patting with a lint-free lens wipe
What is a surface that is not affected by friction during cleaning?
Glass trial lenses (Front surface, bloomed lens and glasses trail lenses are all affected by friction during cleaning)
A projector screen is cleaned by?
A solution of mild detergent (The projector screen is designed to be hilghly reflective)
To extend the life of a slit-lamp bulb?
Use the lowest voltage setting as much as possible
If the bulb contacts become corroded, one may remedy this problem by unplugging the instrument and?
Scrapping with a metal file (The only way to remove corrosion is to scrape it off (alcohol or air will not work))
If a particular fuse repeatedly burns out, one should?
Get professional assistance
One might adjust the concave mirror in an acutity projection in order to?
Improve faulty illumination
A bent, or C-shaped streak in a streak retinoscope is caused by?
A bent bulb filament (A bent bulb filament will cause the retinoscope streak to be distorted which is caused by laying the instrument on its side)
If the retinoscope light flickers and the bulb placement is solid, the flickering is probably due to?
Internal wiring problems
Which of the following is NOT true regarding fluid-filled ultrasound probes?
The probe is filled with steile saline solution (Water filled probes contian distilled water not saline solution)
Ultrasound units are calibrated by?
Touching the probe to a test block specific for that machine
Care of the noncontact tonometer includes all of the following except?
Checking the calibration by firing the air burst again your finger
The muscle light (Transilluminator) might require the following maintenance?
Bulb and battery replacement (The muscle light usually runs on batteries (often rechargable) and will occasionally blow a bulb. The tip may require disinfection (no sterilization) with an alcohol swab (if applied directly to the sclear for transillumination))
When using an automated lensometer, it is important to designate?
Desired cylinder type (An automated lensometer can be set to read in plus (+) or Minus (-) cylinder
An advantage of the automated lensometer is the ease with which it?
Reads progressive add lenses (The most modern automated lensometers make reading a progressive add lens a snap)
All of the following are true regarding automated lensometers except?
The internal lenses and mirrors can be cleaned by removing the instrument housing. (They should be set on an antistatic mat, they should not be placed and used in direct sunlight and the computer components are sensitive to dust are true)
Before adjusting the lensometer eye piece?
Turn the eye piece to the most plus (+) postition (Minus will trigger your accomodative reflex)
If all the lines of the lensometer target clear at the same time, the lens is?
If the narrow/single line and wide/triple lines of the lensometer target do not clear at the same time, then lens is?
If the narrow/single lines are clear and you wish to read the lens in minus cylinder form, you should?
Turn the power-focusing wheel away from yourself (You should turn the wheel away from yourself after clearing the narrow/single line, in order to clear the wide/triple lines)
You have taken the following lensometer reading. The narrow/single line clears at +2.25. The wide/triple lines clear at -0.25. The axis is on 178. The prescription after being transposed is?
-0.25 + 2.50 x 088 (The prescription is +2.25 – 2.50 x 178, transposed you add sphere and cylinder together algebraically: +2.25 + (-2.50) = -0.25 sphere; then change the sign on cylinder: +2.50; Rotate axis by 90(178 – 90 = 088))
You have centered and read the distant portion of the right lens of a pair of bifocals. What is the next step?
Switch to the left lens and note the postion of the target (It is very important to go from distant, right lens to distant left lens, without moving the stage. Otherwise, you could miss induced vertical prism)
The power of a bifocal will be the difference between?
The point where the narrow/single lines clear on the distant part of the lens and where they clear on the bifocal
The distance portion of the lens prescription is -1.25 sphere. You are now reading the bifocal add, and the lensometer dial reads +1.50. The add should be recorded as?
+1.75 (+3.00 – (+1.75) = +1.25)
The best method for reading the add on a no-line progressive lens using a manual lensometer is to?
Mark the lens first using the template from that manufacture (Most companies who manufacture no-line progressives have a template for their lens. The lens is laid on the template and a wax pencil is used to trace the marking onto the lens. A circle indicates where the reading should be taken)
To read the bifocal portion of an aphakic spectacle lens?
The distance and bifocal spherical power should be read with the temples toward the technician
Regarding the power of the midlevel trifocal lens segment?
It is always twice (2x) the power of the trifocal (Even though the middle portion of most trifocals if half the add power, it is not always so. The lens can be read on a lensometer)
Lenses that are not correctly centered on the visual axis result in?
Unwanted prism (Visual axis is the line from the fovea through the pupil)
If the target can be centered in the lensometer, how does one determine whether or not there is induced prism due to decentration?
By marking the centers and observing the glasses on the patient (looking at the marked lenses on the patient will show if there is induced prism because the centers of the lenses will not line up with the patients visual axis)
The target of the right lens is displaced to the right and the lines cross at the third ring. the prism power and direction is?
3 prism diopters base in (Because the lines cross at the third ring you know there are 3 diopters. An image displace to the right in the right lens is displaced nasally, so the base is in)
The target of the left lens is displace to the right, and the lines cross between the first and second rings. The prism power and direction is?
1.5 prism diopters base out
Base out prism is induced when?
The optical center-seperation is less than the pupillary distance with minus lenses (Remember that a minus lens is made up of prisms aligned apex-to-apex. If the pupillary distance is weider than the optical center seperation this would place the visual axis temporal to the center; hence, base out)
To check a manual lensometer for accuracy?
Adjust the eye piece then read a trial lens
Corneal curvature can be recorded as?
Which of the following is an example of oblique astigmatism?
-4.25 + 2.75 x 046 (oblique astigmatism means the axis are not vertical or horizontal, but at an angle in between, NOTE: That the axis do not have to be “on the dot” at 90, 180, 45 or 135 to qualify)
Of the following, which patient is most likely to have irregular astigmatism?
Surface ocular trauma (this is the most common cause of an irregular astigmatism)
The steepest part of the cornea is the?
Center (Cornea is the steepest in the center then flattens out toward the periphery)
The diameter of the corneas optic zone, or cap measures?
4.0 mm (by definition, the corneal cap or optic zone is the central 4.0 mm of the cornea)
Manual keratometry would not be the most appropriate method for reliable measurements in which of the following cases?
Monitoring keratoconus (Key phrase here is “most appropriate”, because the keratometer evaluates a tiny section of the cornea (3mm), it would be more accurate to follow keratoconus using corneal topography)
List the steps of using a keratomoter in chronological order?
1. Focus the eye piece 2. Position the patient 3. Occlude the eye not being tested 4. Focus the mires and center the cross-hairs in the lower right hand circle 5. Turn the drum so that the horizontal plus signs are alligned exactly tip-to-tip 6. Turn the dials to superimpose the horizontal plus and vertical minus signs
You are attempting a K reading and do not see both horizontal plus signs. This may be due to?
A keratometer occluder in the way (the plus sign is projected on the side and the main thing that would obstruct the mires from the side is the occluder (a common vertical obstruction (-) is the patients upper lid))
Karatometer mires appear distorted, small and cannot super impose
Keratometer mires appears Round
Keratometer mires appear small
Keratometer mires appear clear, then quickly blur
Keratometer mires appear elliptical
If the cross-hairs of the keratometer are not centered during the intial reading for contact lens fitting?
The fit may be inaccurate (If the cross-hairs are not centered, you are not reading the corneal apex, because the corneal periphery is flatter, the resulting fit will be to loose when place on the steeper corneal apex)
K readings in a contact lens – wearing patient may be used to evaluate all of the following except?
Lens coverage (the keratometer can be used to evaluate corneal steepening by taking a series of readings over time. Corneal warpage is eviden by distorted mires. The fit of a contact lens can be evaluated by the appearance of the mires and whether they clear/blue before or after a blink)
Which of the following types of astigmatism is NOT obvious when measuring with the keratometer?
Lenticular astigmatism (Lenticular astigmatism is caused by the crystalline lens, which is not detected with the keratometer, but by noting a difference in the amount of astigmatism found on keratometry and that found on refractometry)
You are taking a K reading. The power drum is at 52.00 D (the upper limit of the scale) and the mires are still not alligned. To extend the range of the keratometer, you should?
Affix a +1.25 D trail lens over the aperture (Past upper range of 52.00 D affix a +1.25 trial lens, If below the lower range, then use a -1.00 trail lens)
You have taken a K reading by extending the instruments range. To get the correct value you can?
Use a conversion chart (If math is derired for an extended range upward multiply by 1.1659, for extended range downward divide by 1.1659)
You are adjusting the keratometer eye piece by looking at the occluder through the ocular. The mires are distorted, you should?
Return to the manufacture for cleaning
True or False: When calibrating the keratometer with the metal balls, you should handle the metal balls with your fingers?
False (Do Not handle chrome balls with your fingers, use a tissue or magnet. Oils from the fingers can cause the chrome to corrode changing the readings)
If calibration of the keratometer reveals a discrepancy?
Have the manufacturer repair it
Which of the following is a legal regulation?
The patient who has a refractive eye exam must be provided with a copy of the glasses prescription (expiration date varies state to states but the minimum will be 1 year)
OSHA has developed laws regarding?
Eye protection in the workplace (OSHA deals with employee safey and has rules regarding eye protection in the work place)
True or False: The federal trade commision (FTC) has regulartion affecting the “intraocular lens implant rule”?
True or False: OSHA regulations regarding medical practices require that all contact lenses must be fit by a licensed eye care practitioner?
True (OSHA does not legislate prescribing or dispensing of medical devices)
The “Red Flags Rule” was developed by the FTC in order to prevent?
Identity theft (rule requires businesses (including medical practices) to deveop a plan of identifying relevant patterns, practices and specific forms of activity – the “Red Flags” – that signal possible identity theft)
True or False: The patient protection and affordable care act (PPACA) enforces health care privacy laws?
Which of the following does not carry with it the “duty to report”?
At its most basic, the duty of a scribe is?
Personal assitant to the practitioner (Scribing is essentially being the practioners right hand. While the mian duty may be documentation, the scribe also preforms other duties at the physican’s discretion, including patient education, coordinating patient flow and overseeing billing forms and char work)
True or False: Telling a patient “The risk of developing glaucoma after surgery is so miniscule that you do not have to worry about it” is appropriate when explaining the risks of cataract surgery?
False (Telling a patient that the risk is so small he/she “does not have to worry about it” is discounting a viable risk and suggests a guarentee that it will not happen)
The destruction and inhibition of micro-organisma on any surface (living or inanimate)
The effectivness of a sterilization method is based on?
Destruction of bacterial spores
Sanitation can be described as?
“Clean enough to be healthy” (Sanitation is cleanliness, no destruction or reduction of spores. It may involve something as simple as disposing of paper wrappers)
The organism that may contaminate ophthalmic solutions, including fluorescein and can destroy an eye in 48 hours is?
Pseudomonas aeruginosa (Known to contaminate eye drops)
Universal precautions generally apply to tears (lacrimal secretions)?
If they are bloody (Certain fluids always fall under universal precautions procedures, such as blood, semen, veginal secretions, vitreous and wound exudates. Fluids that become of concern only when blood is visible in them include tears, sweat, feces and urine. While HIV has been isolated in human tears, it is not considered to be in high enough concentration to spread the disease)
Use of eye drops would be advantageous?
If exterior parts of the eye are being treated
All of the following are exmples of systemically administered drugs except?
Timolol eye drops for glaucoma (Eye drops are topical, not systemic)
A topical ophthalmic drug preparation is considered unsterile?
Once it is opened
All of the following should be done prior to pupil dilation except?
Reasons that a patient fail to take his or her glaucoma meds properly include all of the following except?
He/She understands the serious nature of the disease
If a patient has a localized allergic reaction to a topical medication instilled in the office, one should?
Irrigate the eye properly
A patient having an allergic response involving shallow respiration should be given?
Oxygen from a portable unit (If the patient is breathing, give him/her oxygen. Do not give artifical respiration to a person who is breathing on his/her own)
Coodinated movement of both eyes in the same direction is known as?
The movement of one eye alone
If one eye is obviously turned in, out, up or down when you preform a simple external evaluation of the patient, this deviation is a?
Tropia (Unless it is intermittent, a tropia is there all the time. if you can look at the patient and see that one eye is turned, it is a tropia. A phoria is evident only when you cover one eye or otherwise disrupt fusion)
Testing ductions is useful in differentiating cases of?
Restrictive strabismus (Testing ductions is useful when one eye is at fault for a deviation, as in restrictive strabismus)
You have covered the patients right eye. When you uncover it the right eye moves inward. Now, you cover the left eye and when you uncover it, the left eye moves inward. At this point, you can only deduce that the patient has?
Exodeviation (The eyes must have drifted out (i.e. toward the temple) under the cover if they make inward movements when uncovered)
To test the right inferior rectus (RIR) and the left superior oblique (LSO) muscles, the patient must look?
Down and to the right (Looking down and right (from patient perspective) requires RIR and LSO; RSR and LIO are up and right; RSO and LIR are down and left)
Your patient is looking down and to the left. Which muscles are pulling the eyes into this position?
Right superior oblique (RSO) and left inferior rectus (LIR)
You want to check the action of the right lateral rectus (RLR) muscle. Where do you direct the patient to look?
To the right
You want to check the action of the LIO muscle. Where do you direct the patient to look?
Up and right
Ductions refer to?
Movements of one eye (Muscles that work against each other in the same eye are antagonists. Movements of both eyes in the same direction are versions. movements of both eyes in opposite directions are vergences)
Testing ductions is useful in differentiating cases of?
Restrictive strabismus (Testing ductions is useful when one eye is at fault for a deviation, as in restrictive strabismus)
The difference between a phoria and an intermittent tropia is?
The phoria usually is controlled, and the intermittent tropia sometimes is controlled (A phoria is usually controlled unless fusion is disrupted, when disruption is removed the eyes will fuse again. An intermittent tropia comes and goes when the patient is fusing, the deviation appears)
An adult patient with a tropia has either?
Diplopia or suppression (An adult with a crossed eye either has learned to suppress the image from the eye that is not fixating or has double vision. Usually suppression is learned in childhood as the visual system is developing; the brain learns to ignore the image from a crossed eye. In cases where strabismus occurs as an adult diplopia occurs because the brain does not know how to suppress a second image. It is not a given that amblyopia or anisometropia exist, although they might. Fusion and stereopsis can occur only when both eyes are working together, looking at the same object)
Vertical deviations are conventionally described by indicating?
The high (up-turned) eye
The eyes look crossed, but actually are straight (pseudostrabismus is false strabismus, the eyes falsely appear to be crossed although they are straight)
Pseudostrabismus usually is seen in?
Infants (Because infants have a flat nasal bridge and (sometimes) eopicanthal folds, they are imp.icated more often in pseudostrabismus (an optical illusion of esotropia) then any other group)
The most common complaint in a NEW nerve palsy is?
The purpose of covering one eye with an occulder for strabismus screening is to?
Disrupt fusion (fusion will hold a phoria and often an intermittent deviation in check, so fusion must be disrupted in order to determine if these deviation exhist)
Cover testing can be performed even on an infant because?
It is objective (they are based on observation of the examiner rather then the responses of the subject and are therefore objective)
The patient vision is 20/20 in both eyes. You cover the patients right eye and note that when you do so, the left eye moves outward. When you uncover the right eye neither eye moves. When you cover the left eye, the right eye moves outward. When you uncover the left eye, neither eye moves. This indicates?
Alternating esotropia (An outward motion upon uncovering indicated that the eye has drifted in, denoting an esodeviation. In this case, regardless of which eye is covered the covered eye drifts in. When the eye is uncovered it does not move to take up fixation (indicating a tropia). the patient is willing to use either eye to fixate, revealing an alternating esotropia)
During the cover/uncover test, if a patient has a phoria, the response of the eye that is NOT covered is to?
Remains straight (In a phoria, the eye under the cover drifts, the eye that is not covered is fixating, when you remove the cover, the resulting diplopia causes the deviated eye to move, in order to pickup fixation. The eye that was not covered is fixating already, so it does not need to move)
The alternate (Cross) cover test does NOT reveal?
A phoria vs a tropia (It reveals a horizontal or vertical deviation )
When performing the aternate (Cross) cover test, it is important to?
Move the cover rapidly from one eye to the other (Move it form one eye to the other, but every 1/2 second is too fast. It is important to prevent the patient from seeing with both eyes at once and regaining fusion)
You have preformed the alternate (Cross) cover test and notice that each eye moves inward when uncovered. What is your next step?
Preform a cover/uncover test (We do not know if it is a phoria or tropia, just that there is an exodeviation)
The alternate (Cross) cover test can be used to measure the size of a deviation if?
It is combined with prisms (this test combined with prisms to measure the size of deviation (phoria or tropia) becomes the “prism and cover test”. The deviation can be measured in a patient with fusion because the test itself disrupts fusion)
Which of the following is NOT a component of binocular vision?
Identical images on each retina
Uses environmental “clues” (Depth perception is not the same as binocular or stereo vision. A person with one eye can deveop depth perception by learning to use “clues” from the environment, such as overlap, grayness or merging)
Stereopsis is recorded in?
Seconds of arc
Which of the following indicates the better stereo vision?
25 seconds of arc (25 seconds of arc indicates finer stereo discrimination than 50 seconds of arc)
Stereopsis can be elicited and measured in which of the following patient?
8 diopter intermittent exotropia (A patient with a constant esotropia or exotropia over 10 diopters will not have stereo vision, no will a monocular patient. A Binocular patient with an intermittent deviation, a phoria, or a deviation of 10 diopters or less should have a stereo acuity test preformed)
Stereopsis differs from depth perception in that?
Depth perception is monocular or binocular (Stereopsis is present only in binocular individuals depth perception, however, exists in binocular and monocluar patients. Stereopsis is not learned, depth perception is)
While it does not give a measurement, a simple stereo test that can be done at bedside is the?
Pencil point to pencil point test
You ask a cooperative 3 y.o. girl to touch the wings of the Titmus fly. She recoils and refuses. You can assume most likely?
She has at least gross fusion (The fly was choosen as a test object because it is repulsive. An othersie cooperative child may refuse to touch the fly because it is ugly and appears to be real. Refusal is generally considered a positive indication that gross stereopsis exhists)
You are testing an intelligent 12 y.o. boy with the Titmus/Wirt circles and suspect that he is either a good guesser or a cheater. you should?
Turn the test 180 degrees (Turning the test 180 will chagne the location of the stereo rings and make them appear sunken instead of elevated)
An advantage of the Random Dot E over the Titmus test is that the Random Dot E?
Does not offer monocular clues
When evaluating congenitial nystagmus all of the following might be noted except?
Binocular or monocular (Because both eyes will jerk, the direction should be noted as well as magnitude. In some the jerking is lessened when the eyes are in a specific position, so the patient may adopt a head tilt or turn to quiet the eyes)
A patient with nystagmus might find that which of the following decreases the magnitude of the jerking?
Positioning the head
During visual acuity testing and refractometry, it is important to remember that which of the following might cause a worsening of nystagmus?
Occluding one eye
True or False: Children will frequently outgrow congenital nystagmus?
True (Nystagmus is often associated with lesions in the optic system. finding a head position to help quiet the jerking is called the “null point”)
The term minor surgery can be defined as?
A simple procedure with minimal risk
The procedure for removal of a fleshy encroachment onto the cornea is a/an?
Pterygium excision (A pterygium is a fleshy growth that extends from the conjunctiva onto the cornea. It is removed because it can grow across the front of the cornea, impeding sight)
A sterile tray for a lacrimal evaluation might include?
Medicine glass, punctal dilator, syringe and lacrimal cannula
A sterile tray for any growth removal will probably include?
Scalpel, scissors, forceps, needle holder and sutures
All of the following can cause stains on surgical instruments except?
Residue from sutures (Failure to rinse off detergents, minerals in the water source and dried blood can cause stains)
Which of the following is true regarding ultrasonic cleaners?
Instruments should not touch while in the unit (Ultrasonic cleaners do not sterilize, you do NOT have to scrub first, and you can put glass in them, but the instruments should not touch)
The premise behind refractive surgery is to change the refractive power of the eye by?
Altering the eyes focal lenth (The focal length of the eye (or of any lens/lens system) is the distance from the lens system to the focal point, where light is focused. Refractive surgery seeks to alter this in order to put the focal point directly on the retina)
To correct myopia with laser refractive surgery, the goal is to?
Flatten the corneal center (Flattening the corneas center moves the eyes focal point back toward the retina. In myopia, the focal point falls somewhere in the vitreous) NOTE: the Myopic eye has to much plus (+) power which is why we neutralize it with minus (-) power
In which of the following refractive procedures is a corneal flap created and laser used to sculpt the underlying tissue?
LASIK or laser assisted in-situ keratomileusis (in LASIK surgery, a microkeratome (A keratome is a surgical knife/blade used to incise the cornea, a microkeratome is small and capable of making very precise incisions) is used to cut a thin flap in the top-most corneal layers. The excimer laser is then used to sculpt the underlying tissue to correct the refractive error. the flap is then put back into place over the ablated area)
Laser refractive surgery is preformed with which type of laser?
Excimer (the name excimer is dervied from the word “excited dimer”. The alser uses ultraviolet radiation that breaks or photevaporates chemical bonds between tissues and is ideally suited for work on the cornea)
In LASIK, which corneal layers are excised as part of the flap?
Epithelium and Bowman’s layer
Which of the following allows the surgeon to customize laser refractive surgery during the procedure?
Wavefront LASIK (Wavefront technology creates a rough map of the patients eye allowing precise control and treatment. The idea ia to reduce aberrations thus reducing side effects like glare, halos and blur)
True or False: Post op instructions following LASIK surgery would include showering from the neck down, wearing a shield at bedtime and do not rub the eye?
True (Patients are told to avoid water/sweat in the eye, do not rub the eye, wear the shield at bedtime, avoid smoke and not to wear make-up)
Used to treat corneal scars
Phototherapeutic Keratectomy (PTK)
Involves use of a keratome
LASIK and LASEK
Corneal epithelium removed
PRK and sometimes Phototherapeutic keratectomy (PTK)
Very thin corneal flap
Treats some types of corneal dystrophy
Phototherapeutic Keratectomy (PTK)
corneal flap includes some stroma
Routine use of a post-op bandage contact lens
Phototherapeutic keratectomy (PTK) and PRK
Laser stand for?
Light amplification by stimulated emission of radiation
Which of the following is not a medication used in intraocular injection?
Pilopine (Pilopine is a topical miotic gel sometimes used in the treatment of glaucoma)
True or False: The use of a blunt-ended Cannula would be apart of the tray set-up for an intraocular injection?
False (Fine toothed forceps are used to keep the eye in postition by grabbing the conjunctiva)
The prep for an intraocular injection involves?
Use of povidone iodine directly on the ocular surface
YAG stand for?
Yttrium-aluminum-garnet (A reference to the crystals that emit radiation when stimulated by an energy source)
The YAG laser might commonly be used for which of the following procedures?
Cutting through vitreous adhesions (A complication of ocular surgery is where the vitreous pushes out the posterior segment and into the anterior chamber. In this case their is concern that the vitreous pulling on the retina (to which it is still attached) may cause a retinal detachment. if the vitreous has adhered to a surgical incision, it may also be a conduit for bacteria to enter the eye. In such a scenario, the YAG laser is used to cut through the vitreous strand in a procedure known as vitreolysis)
A possible complication of a YAG capsulotomy laser procedure is?
Rise in intraocular pressure
All of the following are acceptable sterilizing procedures except?
Which statement regarding autoclave steriliaing procedures for ophthalmic instruments is false?
Instruments should be closed (they should be open to expose all surfaces)
The minimum time for instrument sterilization in a cold chemical bath is?
All of the following are commonly used for chemical sterilization except?
Iodine (Phenol derivatives, ethyl alcohol 10% and fermaldehyde are all commonly used for chemical sterilization)
Site identification can be accomplished by all of the following except?
Marking the skin with a wax penicil
Which of the following is proper technique when scrubbing?
Rinse from hand to elbows, hands up (Scrubbed arms are held hands-up when rinsing so that run-off goes toward the elbows and not back over the hands. The scrub suit, head cover, shoe covers and mask should all be donned prior to scrubbing. Water should be tolerably warm and the scrub extends to include the forearm)
True or False: Gown cuffs are stretched over the glove cuffs?
False (Glove cuffs are stretched over the gown cuffs. An unscrubbed person may tie the gown as long as they do not touch teh front of the gown or any part of the tie that touches the front. The parts of the gown that are considered unsterile is the neck, the arm pits, the shoulders, the cuffs, the back and any area below the surgical field)
The technique of using the cuffs of one’s sterile surgical gown to handle sterile gloves while putting them on is?
Closed gloving technique (The closed gloving technique, also called the cloased cuff gloving technique, incolces putting the arms through the sterile gown up to the point of the cuffs. The hands, still inside the gown cuffs, are used to minipulate the gloves without touching them directly)
How should members of the scrubbed surgical team move about the OR?
Passing eachother face to face
A common mistake in preforming skin prep prior to ocular surgery is?
Scrubbing back and forth
Hemostatis refers to?
Stopping blood flow (Homo – meaning blood, Stasis – meaning standing or still. Hemostasis is stilling the flow of blood. A surgical assistant may be asked to stop blood flow by applying pressure or other means)
Identify muscles, grasp IOL loops
Holding suture needles
opening obstructed canals
The main purpose of a biopsy is to?
Determine the type of lesion (In a biopsy, tissue is sent to a lab for identification. Usually the concern is whether or not the tissue is malignant (Cancerous))
The surgical procedure where skin or other tissue is transplanted from one part of the body to another is?
Graft (NOTE: When a flap is performed, the tissue to be transplanted is not totally removed, but left partially attached and rotated to cover the adjacent area needing repair)
True or False: Punctal occlusion is a procedure that many patients with dry eyes might have?
True (Punctal occlusion is sometimes used to prevent tears from draining off the eyes surface. Occlusion keeps the tears that are produced (Not much in a patient with dry eye) on the eye)
Which of the following might need to be surgically removed because it is growing across the cornea?
Pterygium (A pterygium is a piece of fleshy tissue that grows from the conjunctiva onto the cornea. An “active” pterygium continues to grow and may need to be removed before it gets to the center and obscures vision)
Surgery that is preformed in order to correct hyperopia, myopia and/or astigmatism is classified as?
Refractive surgery (Technically any surgery that purposely alters the eyes refractive status could be considered refractive surgery, making cataract extraction with IOL implant the most preformed refractive surgery)
Symptoms of cataract include?
Becoming more nearsighted (As the lens opacity gets denser, the eye generally becomes more nearsighted or myopic. This can happen even in a farsighted/hyperopic eye and is known as a myopic shift. A person who needed glasses to read may now find he/she no longer needs them. This is known as “second sight” or the “honeymoon” stage of cataracts)
Another possible symptom of cataract include?
Ghost Image (the scattered light can cause objects to be doubled, although “ghost image” is usually a better description)
Another common symptom of cataract include?
Change in color vision (Cataracts tend to cause a yellowing to a person’s color vision. Often after cataract surgery, a patient will notice that colors are more vivid)
Your patient says his neighbor had her cataracts removed with laser and want to know if his will be taken off in the same way. You tell him?
“No, She is probably referring to the way we use ultrasound to break the cataract into tiny pieces. It is not actually a laser” (Because laser is used to treat post-op capsule opacity, people often think that the cataract is removed that way as well)
The vision a patient may have after cataract surgery can be estimated with?
PAM – Potential acuity meter (A PAM is used to estimate what vision will be once a cataract is removed)
Prior to cataract surgery, an A-scan is used to?
Measure the length of the eye (The A-scan ultrasound is used to measure the axial length of the eye prior to cataract surgery. It is one of several variables in determining the power of an IOL implant to be used once the cataract has been removed)
Which gives the most accurate idea of a cataract patients visual disability?
BAT – Brightness acuity tester (The results of the BAT can indicate a level of disability that is not evident on testing with the regular snellen eye chart. Cataracts that are dense in the center can often cause vision to worsen in bright light because the pupil constricts. The BAT gives an actual measurement of how much worse the vision is in such bright conditions)
True or False: Intraocular pressure is used in IOL calculations?
False (Pressure if not relevant to the actual calculation, K-readings, Desired post op refraction and an A-scan are used in IOL calculations)
Currently the most commonly used type of anesthesia for cataract surgery is?
The term “secondary cataract” is misnomer because?
Once removed, a cataract cannot grow back
Insertion of a phakic IOL would be done for the purpose of?
Correction of refractive error (A phakic IOL is inserted into the eye without removing the natural crystalline lens. It is done for the purpose of correcting refractive error)
Laser treatment for primary/chronic open angle glaucoma is a/an?
Trabeculoplasty (The laser beam is aimed into the angle of the eye (between the cornea and iris root). The theory is that when the tissue heals, the scarring pulls the trabecular meshwork open increasing aqueous outflow)
A surgically created, conjunctiva-covered external opening trough which aqueous can drain is a?
Bleb (In glaucoma surgery using a valve, a “bubble” or bleb is created between the conjunctive and sclera as a site for venting aqueous from the eye)
Angle-closure glaucoma is most often treated by preforming a?
Laser iridotomy (In angle-closure glaucoma, the iris butts up against the anterior lens surface and is then pushed into the angle of the eye blocking the drainage of aqueous from the eye. A laser iridotomy is done to create an opening in the iris to allow the aqueous to drain even when the angle is blocked)
In the event that the eyeball is removed, an implant is placed into the orbit. The purpose of this implant is to?
Maintain the shape of the orbit (Without the implant the shape of the orbit would tend to shrink, making it difficult to fit a prosthetic eye)
Hypertension is when, most of the time, the blood pressure is equal to or greater than?
140 systolic and/or 90 diastolic (Currently the designation of hypertension states when a person’s blood pressure is consistantly 140-149 systolic (or higher) and/or 90-99 diastolic (or higher). There is also a category known as “prehypertension”, which ranges from 130-139 systolic and 80-89 diastolic. If the systolic is 180 or higher and/or diastolic higher than 110, emergency care is called for)
True or False: Toxoplasmosis, herpes simplex and gonorrhea are all infections that can be present at birth?
True (If the mother is infected with toxoplasmosis, herpes simplex or gonorrhea the infant is at risk. Toxoplasmosis would occur inutero, herpes simplex and gonorrha at birth)
Name 3 symptoms that are often seen in a patient with AIDS?
Dry eye, recurrent blepharitis, Optic Neuritis and reccurent conjunctivitis (AIDs patients can also develop xanthelasm (yellowish lid lesions related to cholesterol) but in general is not directly associated with AIDs)
True or False: Smoking can cause ptosis, trichiasis and retinoblastoma?
False (Externally smoking can contribute to dry eye; also increases the rish of retinal diseases, including diabetic and hypertensive retinopathy and macular degeneration; also can cause tabacco amblyopia (which is a visual decrease in an otherwise healthy eye due to smoking))
Sagging and eversion of the lower eyelid is termed?
Ectropion (extropion is a sagging, everted (out-turned) lid)
Infection of the lash follicle is a?
Hordeolum (An infected lash follicle produces a stye or hordeolum (A chalazion is an infected meibomian gland))
An infected meibomian gland causes a?
Infection of the lacrimal sac is termed?
Dacryocystitis (Canallulitis is an infection of the canaliculus)
Redundant skin of the lids is referred to as?
Dermatochalasis (The term dermato – indicates a condition involving the skin; the suffix chalasis means relaxation
The condition where the lacrimal gland slips down under the conjunctiva is known as?
Prolapse (A prolapse occurs when a structure slips out of place. The lacrimal gland can “fall” into the space between the globe and the conjunctiva, appearing as a yellowish, moveable mas under the conjunctiva on the superior area of the globe)
True or False: Burning, epiphora (streaming tears) and gritty foreign body sensation are all a symptom of dry eye?
Slit-lamp exam of your patient reveals a yellowish nodule on the conjunctiva just nasal of the cornea. Most likely this is a?
Pinguecula (A Pinguecula appears as a yellow nodule, usually on the nasal side of the eyeball. A Pterygium crosses onto the cornea, and the nodule associated with spiscleritis generally is seen in red eye. Xanthelasma appears on the lids)
True or False: Yellow crusting is a common indication of viral conjunctivitis?
False (Crusting is usually associated with bilateral conjunctivitis. Photophobia, recent sore throat and moderate redness are all associated with viral conjunctivitis)
True or False: Epidemic Keratoconjunctivitis (EKC) is caused by a bacterium?
False (EKC is caused by a virus, the conjunctiva and usually the cornea are involved)
Neovascularization of the cornea is generally related to?
Lack of oxygen (Neovascularization (in any part of the body) is the growth of new blood vessels. In the cornea, this is due to anoxia or lack of oxygen. It is commonly associated with contact lens wear.)
Your patient has an abrasion of the corneal epithelium. All of the following are true except?
There will likely be a corneal scar (If only the corneal epithelium is involved, there will be no scarring. Corneal scaarring generally occurs if the abrasion reaches the deeper stroma tissue)
When asked about previous eye surgery, your patient says that she once had “a piece of skin removed that was growing onto the clear part of my eye.” Most likely she is describing?
Blood in the anterior chamber of the eye is a?
Hyphema (hyphema (hema referring to blood) denotes the presence of blood in the Anterior chamber. it is usually graded by the amount of anterior chamber involved. A 50% hyphema would mean that half of the anterior chamber is filled with blood. A 100% hyphema is sometimes called an 8-ball hyphema, because the filled anterior chamber looks like a black 8-ball)
What is the term that referes to a layer of inflammatory cells/pus in the anterior chamber?
Hypopyon (A hypopyon is the presence of white blood cells in the anterior chamber, it usually signals the presence of an infection)
Which of the following indicates a risk for open-angle glaucoma?
A family history of glaucoma (Open angle glaucoma has no physical symptoms and tends to be hereditary. Halos around lights at night are sometimes associated with angle-closure glaucoma)
Because of elevated intraocular pressure, a child born with glaucoma has?
Buphthalmos (An infants eye is more elastic than an adults so elevated intraocular pressure tends to distort and distend the globe. This causes buphthalmos or “ox eye” in which the cornea takes up most of the palperbral fissure)
True or False: Risk factors for glaucoma include; positive family history, african-american heritage and ocular trauma?
True or False: Generating public interest is a problem common to public glaucoma screening programs?
False (The fact that glaucoma screening generates public interest is not a plague but a benifit)
The diagnosis of glaucoma may be based on what kind of tests?
Tonometry, perimetry, ophthalmoscopy and central corneal thickness (The classic hallmarks of glaucoma are increased IOP (tested with tonometry), loss of peripheral vision (evaluated with formal perimetry) and damage to the optic nerve head (As seen on ophthalmoscopy). Because a thin cornea is also associated with increased risk of glaucoma, a central – not peripheral – corneal thickness measurement is also taken)
The apperance of halos around lights during an attack of angle-closure glaucoma is due to?
Corneal edema (Corneal edema has a prismatic effect, breaking light into its component colors and thus creating halos around lights. Pressure build up during an attack causes a breakdown in the pumping function of the corneal endothelium and edema results)
In open-angle glaucoma?
The angle looks normal
A patient in the end stages of open-angle glaucoma?
May have a small temporal island of vision
A dislocation of the crystalline lens is termed?
Luxated (A luxated lens is dislocated; a subluxated lens is only partially dislocated. Lens dislocation may cause iridodonesis, where the iris seems to vibrate or shake because its support, the lens, has shifted or been lost)
True or False: Dizziness and nausea is a sign and symptoms of uveitis?
False (Redness is generally more marked at the limbus. Light sensitivity may be severe and the pupil is generally smaller)
True or False: The symptoms of a Retinal vein occlusion are easily distinguished?
False (Because the symptoms of a retinal vein occlusion are so similar to those of a retinal artery occlusion, the patient with sudden, painless loss of vision should always be triaged as if it were a retinal artery occlusion. If a vein is occluded blood can still come into the eye via the arteries, but blood drainage from the retina is blocked or slowed. Happens most often in patients with high blood pressure and there may be a generalized blurring of vision or a field loss in an area related to the part of the retina that has been affected)
What is commonly seen in open-angle glaucoma?
Optic nerve cupping (Optic nerve cupping is where the high IOP has killed axons, leaving empty space)
True or False: Albinism, Retinitis Pigmentosa and Coloboma are hereditary?
Chemicals from the endocrine glands travel to the target organ through the?
Bloodstream (Hormones are released into the bloodstream and are carried to the target organ)
Which order represents human circulation?
Capillaries, veins, heart, lungs, heart, arteries, capillaries (It is a continuous cycle)
The human nervious system is divided into which 2 structural parts?
Central and peripheral
Most of the blood supple directly to the eye is supplied by the?
Ophthalmic artery (Ophthalmic artery is the main blood source that enters the eye directly. The vein conducts blood OUT of an organ while the artery conducts blood INTO an organ)
True or False: Plasma is a component of the tear film layer?
False (The tear fild is made up of mucin, water and oil)
the ocular media consists of?
The tear film, cornea, aqueous, vitreous and lens (The ocular media are the transparent structures of the eye through which light passes)
True or False: The retina is part of the optical media?
Which ocular structure refracts light the most?
Cornea (Light entering the eye is refracted 3/4 by the cornea and 1/4 by the remaining optical structure. Average lens has about 20 Diopters of plus power, the cornea has 43 diopters)
How many muscles make up the iris?
2 (The 2 muscles of the iris are the dilator (opens the pupil) and the sphincter (closes the pupil))
Which of the following structures is responsible for aqueous production?
Ciliary Body (Aqueous humor is formed by the ciliary body which joins the iris and the sclera. The ciliary muscle controls the shape of the lens via accommodation)
True or False: The hard, central core (nucleus) of the lens is formed as lens fiber layers are produced and compacted together?
True (An infants lens is soft throughout, like putty. The hard central core forms as layers laminate over time as we age)
True or False: The crystalline lens is in the anterior chamber?
False (The lens is in the posterior chamber which lays behine the iris)
When a person looks at a near object?
The ciliary muscle contracts, causeing the zonules to relax, causing the lens to thicken (We need more plus (+) power to view close up objects. When the circular ciliary muscle contracts, the zonules are allowed to relax, taking tension off the lens and allowing it to “relax” and thicken causing more “plus (+)” power)
True or False: The retina is part of the uvea?
False (The uvea consists of the iris, ciliary body and choriod)
True or False: Cone rods outnumber the rods 20-1?
False (Cone cells are concentrated in the foveal area, they are responsible for color and central vision and they function best in daylight. Rods acutally outnumber cones 20-1)
The group that accredits standards in safet glasses and lenes is the?
ANSI or American National Standards Institute (ANSI accredits the standards for a number of industries, products and processes. The standards themselves must go through a specific accreditation process including, among other things, a consensus by experts in the field and input from the public sector)
Because of the crossing of retinal fibers after leaving the optic nerve, an object in the patients right field of view?
Will be projected to the left optic tract
The main features of safety frame include all of the following except?
Do not conduct electricity (Frames approved for safety glasses must be resistant to high impact and marked to identify them. If the temples are thin, extra side shields are required)
The thinnest allowable width for a general wear, impact-resistant glass safety lens is?
2.2 mm (A glass safety lens for general use may be no thinner than 2.2 mm in any part of the lens. The standard for an industrial use-lens is 3.0 mm)
Welders must wear safet glasses or shields that will protect them from?
Ultraviolet radiation burns (The welding arc is ultraviolet radiation and can cause very painful corneal burns)
Your patient complains that he cannot see anything to his left. Which of the following will give the most detailed analysis of this problem?
Automated visual field (A patient with a visual field loss would be most benefited by an automated visual field, which can help determine where in the visual pathway the problem is. An amsler grid tests only the central 10-20 degrees of vision, which is not enough in this case)
A test done to estimate how much of a vision loss is due to cataracts and how much to retinal disease is?
PAM – Potential acuity testing
An established patient returns every months or so complaining of decreasing vision. Refractometry has shown a gradual increase in astigmatism. The most helpful test to determine the cause of this would be?
Corneal Topography (Corneal Topography will generate a map of the corneal curvature and if repeated overtime, may reveal that this patient has keratoconus. The keratometer does not “read” a large enough area of the cornea)
A procedure done to help alleviate dry eye by keeping the tears on the eye is?
Punctal occlussion (In punctal occlusion, the puncti, usually just the lower, are plugged with punctal plugs or sealed with laser or cautery)
Which of the following is used to remove an embedded metallic corneal foreign body?
Spud or Drill (A foreign body spud or small drill may be used to remove a metallic foreign body that has lodged in the cornea. Any rust in the tissue around the foreign body must also be removed)
Botulinum toxin injection or Botox is used to relieve?
Blepharospasms (Botulinum toxin is used to relieve chronic lid twitching or blepharospasms. It also is used in some cases of nonaccomodative strabismus)
A procedure done to resolve angle-closure glaucoma is?
Laser iridotomy (Laser iridotomy is a procedure in which a hole is punched into the iris so that aqueous can still exit the eye, even if the angle is occluded)
Following cataract surgery, the patient may notice?
Vision has a blueish tinge (The cataract has the effect of causing vision to become dingy and yellow. When the cataract is removed, objects are restored to their normal color. However, the patient often perceives this as being “bluer” than his/her preoperative vision)
Following cataract surgery, the final refraction will usually take place?
4-6 weeks after surgery
To secure a pressure patch, it may be necessary to?
Shave the patients facial hair (You may have to shave some facial hair to get the tape to stick to the cheek. If the tape is not tight enough to keep the eye shut, pressure patching is useless)
Your patient has a guide dog. You should guide the patient by?
Requesting that the patient and dog follow up you.
True or False: Scheduling fewer patients will help expedite patient flow?
False (Chart preview, template – style exam forms and protocal for handling phone call will help expedite patient flow)
True or False: Corneal transplant patient with symptoms of rejection is a highly emergent ocular situation requiring treatment within minutes?
False (Sudden, painless loss of vision in one eye (symptoms of a central retinal artery occlusion) might be reversed with rapid treatment, Chemical burns should be irrigated immedicately and because a penetrating injury involves exposure of the ocular tissues to contamination, it is also considered a high level emergency)
Urgent occular situations generally need to be seen in?
Within 24-48 hours
True or False: A Construction worker with a foreign body sensation is an emergency situation?
True or False: Sudden, painless loss of vision in one eye constitutes an emergent complaint?
True or False: A subconjunctival Hemorrhage can cause a pain red eye?
False (A subconjunctival hemorrhage is red, but usually painless. Viral conjuctivitis can be particularly painful)
True or False: Open – angle Glaucoma causes red eye?
The appearance of halos around lights during an attack of angle-closure glaucoma is due to?
In examining the pupil of a painful red eye, which would most likely be seen in iritis?
The affected eye would have a smaller pupil
A 60 y.o. patient calls with flashes and floaters in the eye, which started 2 days ago. You should?
Schedule him/her for an urgent visit (These can be signs of a retinal detachment)
True or False: Ammonia can cause one of the most serious chemical injuries?
True (Ammonia is a base. Bases bind to lipids (fats) in the tissues and thus penetrate deeply. Acids cause surface burns, but do not adhere to the tissue or penetrate)
Before any treatment is started on a patient who presents with a foreign body in the eye, the most important question to ask is?
“What were you doing when this happened?”
It is best to remove a metallic corneal foreign body during the first 6-8 hours to prevent?
Formation of a rust ring (A rust ring forms around a metallic corneal foreign body in 6-8 hours. The rust stains the corneal tissue and must be removed with a drill or burr, or a foreign body spud)
A hemorrhage in the anterior chamber is?
An employer’s written plan regarding employee exposure to blood born pathogens is a?
Exposure control plan (The exposure control plan is part of OSHA’s requirement for employee safety in the workplace where there is potential exposure to blood born pathogens)
The purpose of government required forms regarding ocular health is generally to?
A refraction is usually ruled by medicare as?
A noncovered procedure
Average heart rate in a human adult is?
72 beats per minute (Or somewhere between 70-80 beats per minute)
The average adult human respiration rate is?
18 breaths per minute (Or somewhere between 12-20 breaths per minute)
When checking Blood pressure with a manuel (nonelectric) sphygmamanometer, the examiner holds the membrane of the stethoscope?
Against the skin and inside the elbow
If breathing and pulse are not present, brain death will usually occur?
in 4-6 minuts after pulse and breathing cease
How many people survive cardiac arrest if someone preforms chest compressions or CPR?
1 in 10 (Approximately 1 in 10 victims will survive cardiac arrest if chest compressions or CPR is preformed)
The rate of compressions in hand-only CPR is?
100 per minute
A softer lighting that evenly illuminates the entire subject without highlighting any particular part
The illumination source is shined directly on the area of interest
Highlighting an area of interst by illuminating the structure behind it
Illumination source is shined on another structure than the one of interest
Illumination source is shined at an oblique angle across the surface of a structure
When preforming slit-lamp photography, a photograph of the eye using low magnification and diffuse lighting is recommended to?
Provide orientataion (Before photographing pathology, take a photo of the entire eye using diffuse lighting (the diffuser is a foggy-looking filter that flips up over the slit-lamps illumination source). This helps orient the viewer when photos are examined later as well as provides documentation of the eye’s general appearence)
You are taking a slit-lamp photo of an iris lesion that may be melanoma. The illumination technique of choice is?
Direct (Direct illumination is used for opaque entities (A subject that is more see-through would be better photographed using indirect illumination))
You are taking a slit-lamp photo of a cortical catarat. The illumination tecnique of choice is?
Retroillumination (Using retroillumination, the light reflextion from the retina (giving a bright orange/red background) will show any lens opacities in silhouette)
The method used to take photographs of the endothelial layer of the cornea is?
Specular photomicrography (Specular photomicrography is a special technique used to capture images of the corneas single-layer endothelium. The endothelium does not regenerate and is key in maintaining the cornea’s clarity)
Setting the fundus camera eye piece should be done?
With both eyes open, in dim light or darkness (The eye piece should be set in dim light (or in the dark) with both eyes open. On the fundus camera, this means one eye is looking through the eye piece and the other eye is not)
In order to image eyes with high refractive errors it is best to?
Set the diopter compensation device built into the camera
To take a photo of the external eye with the fundus camera (eg. to document corneal edema that interferes with a clear view of the fundus)?
Change the diopter setting to “+” (If you set the dioptric compensation device to “+”, it is possible to take a photo of the external eye using the fundus camera)
Gross focusing with the fundus camera is generally accomplished by?
Moving the joystick (Gross focusing can be accomplished by moving the joystick. On some fundus cameras, fine focusing is accomplished by turning a focusing knob on the camera. The subject is never focused by turning the oculars or by asking the patient to move. Changing the magnification setting will make the image larger, but not more focused)
Focusing the fundus camera can be simplified by?
Focusing the donut on the patient’s closed lid before composing the photograph (This will put you very close to being in focus when the patient opens his/her eye. It is also more comfortable for the patient and allows you to avoid fubling around with the camera, looking for the eye. If the fixation light is in front of the camera, it will get in the way of the photograph)
You are attempting to take fundus photographs and see a blue-gray halo around the subject. To correct this, you should?
Move the camera closer (Blue-gray halo means you are too far back, a whitish haze means you are too close)
You are attempting to take fundus photographs and notice a whitish haze in the center of the subject. This may mean that?
The camera has drifted to one side
You are centering on the macula when a light yellow cresent appears in the upper left of the viewing field. This is cause by?
Reflection off of the edge of the pupil
You are centering on the macula when a light yellow cresent appears in the upper left of the viewing field. How should you correct this?
Move the camera slight down and to the right (To compensate for a pupil cut, move the camera directly opposite from the crescent)
A key feature of a camera to be used in ophthalmology for external photography is that it can?
Provide enough magnification to image a single eye (External ophthalmic photography is often taken on a 1:1 ratio, where the photograph is life-sized. A Macro lens is often used to enhance image quality when taking close up photos)
Regarding lighting for external ophthalmic photography?
An adjustable “point source” flash is preferred (The point source flash reduces the amount of reflection from the cornea. The flashe is often mounted to the camera with a moveable bracket so the flash can be rotated into the most advantageous postition for the area being imaged. If taking an external image of corneal pathology, the reflection from a ring light might totally obliterate the area of interest)
True or False: When illuminating a subject for external photography, direct the illumination from the nasal aspect?
False (If the flash/illumination is coming from the nasal aspect, the nose and brows may cast a shadow across the area of interest)
Ultrasound employs the use of?
The term A-scan refers to a?
One-dimensional amplitude scan
The “A” in A-scan stands for?
The sensitivity, or electronic amplification, of the sound wave signal
True or False: Computerized corneal topography evaluates 4 points of the corneal apex?
False (Corneal topography avaluates some 6000 points across the entire corneal surface. Keratometry measures only 4 points in the 3 mm central optic zone)
The corneal topography map most commonly used is the?
True or False: Corneal topography is useful in the evaluation of corneal sensitivity?
Heidelberg Retinal Tomography (HRT)
Confocal laser, can be adapted for corneal imaging
Glaucoma Diagnosis (GDx)
C on focal laser, uses polarized laser light
Optical Coherence Tomography (OCT)
Can be adapted for corneal imaging, uses “near infrared” light
A postoperative refractive surery patient is complaining of glare and ghosting. What would provide the most helpful analysis?
Corneal topography (Corneal topography can show the location of the ablation zone. If the pupil does not fall within the central portion of the zone, visual disturbances can occur)
When using scnaning laser as an aid in diagnosing glaucoma, the area of interst is the?
Retinal nerve fiber layer
If your patient complains of blurred vision at near, the most likely cause is?
Need more information (the answer depends on the age of the patient and their previous refractive status)
True or False: presbyopia is delayed in patients who are nearsighteded?
False (Myopia does not delay presbyopia, the myopic eye ages at a normal rate (It is true, however, that a mildly myopic patient might not notice the effects of presyopia until later then average))
A classic complaint of the presbyopic patient is?
“My arms are too short” (The loss of near vision is oftern compensated for by holding reading material at arms length. Thus the patient complains that his/her arms are to short)
An automated refractor reading is especially helpfully when the patient?
Is new and has no glasses
Some autorefractors allow the assitant to manipulate the reading in order to provie the clearest image possible. This pushes the autorefractor into the realm of?
Subjective testing (Subjection testing of any kind involes asking for a response from the patient. Still, the reading would not be prescribed directly under most circumstances, refinement using lenses would still be done. Most autorefractors use the principles of reinoscopy)
Performing an autorefraction after the patient is dilated?
May reveal additional hyperopia (If a patient accommondates during an autorefraction, then the reading may be less hyperopic then the patient actually is. When accommidating the eye adds “more plus” to itself, which the autorefractor responds to by adding more minus)
True or False: Glaucoma could result in erroneous autorefraction measurements?
Error in autorefractor measurement can result from?
Having the instrument in a lighted hallway (Dim lighting is recommended, as peripheral light may inhibit the instrument from aligning properly. Pupillary distance does not factor into the measurement; in fact, many autorefractors measure and provide this information)
In order to avoid compromising the distance measurement, refractometry should be preformed prior to?
True or False: Converging the aperture is an appropriate adjustment to the refractore (phoropter) before starting the distance measurement?
False (Always set the pupillary distance, vertex distance and level before measuring. The apertures are converged to test the reading (near) vision, not distance)
True or False: Fogging may be used to avoid giving to much plus at near?
True (Fogging is used to reduce accommodation during refractometry, which helps prevent giving to much minus. It also can be used instead of occulsion, but is not used to avoid giving to much plus at near)
When offering the patient changes in spheres, a good general rule is to?
Offer most plus first (Always offer more plus first, more minus frequently looks better to an eye that is accommodating and sphere has no axis)
The astigmatic dial is useful for?
Estimating the cylinder axis (The astigmatic dial is useful in estimating the cylinder axis. You still must refine with the cross-cylinder)
The astimatic dial looks like?
A clock face
When using plus cylinder, if the patient says that all the lines on the astigmatic dial seem to be equally clear?
Add +0.50 sphere and ask again if any lines are darker (If you are using plus cylinder and the lines on the dial appear equally black, add a little sphere (ie. move in a more plus direction) and ask again. In minus cylinder, give -0.50, either way you are moving the imgae off of the retina enough to see if there is another meridian of focus)
In plus cylinder, if the patient says that the lines on the astigmatic dial running from 12-6 are clearer, you will set your axis cylinder at?
90 (For plus (+) cylinder, set the cylinder axis PARALLEL to (or in line with) the darkest lines as the patient sees them)
In minus cylinder, if the patient says that the lines on the astigmatic dial running from 12-6 are clearer, you will set your axis cylinder at?
180 (For minus (-) cylinder, set the cylinder axis perpendicular to (or away from) the darkest lines as the patient sees them)
You are measuring a patient from scratch (no retinoscopy, lensometry, or prior records) Your best spherical correction is +2.00 sphere for 20/60 vision. You use the astigmatic dial and find that the lines are equally black with cylinder -1.50 x 180. What is your next step?
Change the sphere setting to +2.75 (for every 0.50 D of minus cylinder, you should add 0.25 D of sphere in the plus direction. This is to maintain equivalence. In plus cylinder, for every 0.50 D of cylinder you should subtract 0.25 D of sphere)
On Cross-cylinder testing?
The axis of the cylinder should always be measured first, then its power (ALWAYS measure the cylinder axis first. If the axi is not refined first, you cannot get the accurate power)
When refining the axis using minus cylinder you should follow which dot on the cross-cylinder?
Red (If you are using minus cylinder and are refining axis follow the red dot. MINUS = RED If you are using plus cylinder, then follow the white dot. PLUS = WHITE)
You are using plus cylinder and are refining cylinder power. The present cylinder power is +0.50. The patient says that the letters are more clear when the white dot is showing on the cross-cylinder. What should you do now?