What molecule acts as a reducing agent in the protection against superoxide?
B. NADPH. These agents are found along the sorbitol pathway. This pathway is important in understanding the breakdown of glucose in the body. One molecule of glucose can either undergo reduction to sorbitol in a low oxygen environment or can be converted directly to fructose 6-phosphate.
Which amino acid is found in the first step in production of epinephrine?
D. Epinephrine is derived from Tyrosine. Tyrosine molecules are converted to dopamine which leads to production and release of norepinephrine. Norepinephrine is converted to epinephrine via methyltransferase.
Tricyclic antidepressants function by increasing _______ levels in the synaptic cleft. (PICK 2)
B/D. TCAs function by increasing levels of serotonin, norepinephrine/epinephrine, and anticholinergic activity. These three functions lead to increased sympathetic output.
What is the mechanism of action of Natamycin?
C. Natamycin is an antifungal that works by inhibiting ergosterol thereby forming pores in cell walls. This leads to cell death. Recall that Natamycin is NOT a macrolide – a drug class that inhibits the 50s subunit of bacterial ribosomes. Penicillins inhibit transpeptidase.
All of the following medications are classified as antifungals, EXCEPT:
C. Oseltamivir, also known as Tamiflu, is used in the treatment of Influenza. The remaining options are antifungals. Of note, Natamycin is NOT a Macrolide as the name indicates.
Which of the following is NOT considered a first generation Oral Antihistamine?
B. Loratidine is an example of a second generation antihistamine. To recall, “phen” in the drug name is a clue to determining first generation – exception of promethazine. First generation antihistamines penetrate the blood/barrier more easily than second generation antihistamines. This leads to less side effects such as sedation.
A patient reports an allergy to Sulfa drugs. Which of the following medications is safe to prescribe?
D. Ciprofloxacin is safe to use in patients with Sulfa allergies. Sulfa drug classes include: Penicillins, CAIs, Sulfonylureas, and Sulfonamides.
Which of the following drug classes function by binding the 30s subunit of bacterial ribosomes? (PICK 2)
B/C. Recall, “Buy AT 30, CEL at 50”. Aminoglycosides and Tetracyclines act by binding the 30s subunit of bacterial ribosomes and preventing protein synthesis. The other three classes work by binding the 50s subunit.
Which of the following antimicrobial medications works by preventing transfer of peptidoglycan into a growing bacterial wall?
D. Bacitracin prevents bacterial wall synthesis by inhibiting transfer of peptidoglycan into the growing wall. Oxacillin and Cephalexin inhibit transpeptidase. Gentamicin inhibits bacterial protein synthesis by binding 30s subunits of the bacterial ribosome.
Which of the following statements regarding Penicillins and Cephalosporins is INCORRECT?
D. If a patient is on Warfarin, it is best to prescribe a Penicillin. Cephalosporins may destroy normal intestinal flora thus altering Vitamin K absorption. This may lead to excessive thinning of the blood in conjunction with Warfarin.
Which of the following medications is contraindicated for use with Phenylephrine?
D. Nardil, also known as Phenylzine, is a Monoamine oxidase inhibitor. MAO is an enzyme found in the synaptic cleft that breaks down norepinephrine and serotonin to be taken back up. By inhibiting MAO, norepinephrine and serotonin may remain active in the cleft for longer. When used in combination with Phenylephrine, there is too much sympathetic activity.
What is the mechanism of action of Digoxin?
A. Digoxin, a medication used in treatment of congestive heart failure, functions by inhibiting Na+/K+ ATPase resulting in increased intracellular Ca2+. Side effects include Retrobulbar Optic Neuritis and/or B/Y color defects.
Which of the following medications function by inhibiting HMG-CoA reductase?
A. Simvastatin, also known as Zocor, is one of three cholesterol medications that function by inhibiting HMG-CoA reductase. This enzyme is responsible for production of cholesterol. These medications are first line therapies. Gemfibrozil binds to PPAR-alpha leading to breakdown of VLDL. Cholestyramine binds bile acids in intestines to prevent reabsorption. Isotretinoin is a distractor as it is used in treatment of acne.
Which of the following diuretic medications is the only medication to affect the Ascending Loop of Henle in the nephron?
D. Furosemide is the only diuretic to affect the ascending loop of Henle. Furosemide functions by inhibiting Na+/2Cl-/K+ co-transporter while also increasing Ca2+ secretion. Use of Furosemide may lead to development of hypokalemia and/or nephrotoxicity.
Which of the following medications used in the treatment of elevated blood pressure does not cause patients to develop a productive cough?
A. Losartan, an Angiotensin II receptor antagonist (ARB) is used to treat hypertension. It does not have any effect on bradykinin activity, thus leaving lungs unaffected for cough. The remaining options are ACE inhibitors which act by preventing formation of angiotensin II through ACE inhibition as well as blocking metabolism of bradykinins causing vasodilation.
Which of the following two arteries supply the occipital lobe? (PICK 2)
A, E: Both the posterior and middle cerebral arteries supply the occipital lobe. Having two vascular branches is the reason behind macular sparing in some patients with traumatic brain injuries.
The major circle of the iris is formed by the anastomosis of the _____ and _____ arteries. (PICK 2)
A, C: MACI is formed by the anastomosis of the long posterior ciliary and anterior arteries. It is located within the iris stroma and is non-fenestrated.
Which of the following regions of the body does NOT drain lymphatic fluid into the right lymphatic duct?
D. The liver is the only region above that does not drain into the right lymphatic duct.
In opposition to the ascending limb of the loop of Henle, the descending limb is permeable to _____ and impermeable to _____.
D. The descending limb of the loop of Henle is permeable to water and impermeable to NaCl. The opposite is true of the ascending limb.
In the proximal convoluted tubule, the Na/K ATPase drives NA+ ___ and K+ ___.
B. In the proximal convoluted tubule, the ATPases drive Na+ out into the interstitial space and K+ in to the proximal convoluted tubule for excretion. Water will follow the Na+
Which cells of the pancreas are responsible for production of glucagon?
A. Alpha cells within the Islet of Langerhans are responsible for production of glucagon. Beta cells produce insulin and amylin. Delta cells produce somatostatin. F cells produce pancreatic polypeptide.
Goblet cells secrete products via which of the following types of secretion?
D. Apocrine secretion – products secreted in membrane-bound vesicles. Holocrine secretion is when the entire cell that contains the product is secreted. Meibomian glands are an example. The main lacrimal gland secretes via merocrine – products move directly into lumen.
Which of the following cells does NOT require an antigen presenting cell when responding to antigens?
A. Natural Killer cells do not require an antigen presenting cell to attack antigens. NK cells serve as the rapid response team for antigens that have yet to be phagocytosed. The remaining cells are part of a specific immunity response.
Which structure within the diencephalon is responsible for regulating body temperature, hunger, and sleep?
D. The hypothalamus is responsible for regulating body temperature, hunger, and sleep. The epithalamus contains the pineal gland which regulates circadian rhythms. The thalamus acts as a relay station for sensory input to different cortical regions. The subthalamus and basal ganglia communicate to control muscle movement.
Which of the Cranial Nerves is responsible for smiling?
A: CNVII – Facial Nerve provides motor innervation to muscles of facial expression. CNV – Trigeminal Nerve is separated into 3 branches. V1 is ophthalmic, V2 is maxillary, and V3 is mandibular. V1 and V2 provide sensory information while V3 provides motor input.
Which muscle is responsible for raising eyebrows?
B: Frontalis muscle is responsible for the look of surprise. The frontalis is activated in cases of ptosis and dermatochalasis to assist with raising eyelids. The corrugator creates the look of concentration. Procerus, think rhinoceros.
Select the bones that make up the lateral wall of the orbit:
B,E: The Greater wing and the Zygomatic bones comprise the lateral wall (Great-Z)
Select all the bones that make up the medial wall of the orbit:
All but C: Recall the mnemonic “the nose SMELs” for medial wall of orbit.
How many bones make up the orbit?
D: Seven – Frontal, Ethmoid, Sphenoid, Lacrimal, Maxilla, Palatine, and Zygomatic
Lateral conjunctival lymphatics drain into the ______ lymph nodes.
B: Preauricular nodes – the site of palpation in cases of red eye. Medial conjunctival lymphatics travel to the submandibular nodes.
Which corneal layer has the most mitochondria?
C: The corneal ENDOTHELIUM has the most mitochondria to supply energy to the Na/K pumps that maintain corneal water concentration.
Which muscle is responsible for keeping the eyelids adhered to the globe?
C: Muscle of riolan is the most superficial portion of the orbicularis oculi and is responsible for keeping the eyelid adhered to the globe.
Muller’s muscle is ______ muscle that is innervated by the ______ system.
C: Smooth muscle that is innervated by the sympathetic nervous system. Mueller’s muscle provides an extra 2-3mm of lift to the eyelids. Loss of innervation to this muscle will lead to a mild ptosis (i.e. Horners)
Which of the following layers of the eyelid contains goblet cells?
E: Palpebral conjunctiva and within caruncle are two sites of mucous production
Which of the following statements regarding inflammation of the eyelids is FALSE?
D. Although inflammation does cause a widening of meibomian ducts, meibum that has become more viscous will block the further secretions. This blockade leads to acinar atrophy, a primary cause of dry eye.
Which of the following ganglia innervate the lacrimal gland?
C. Pterygopalatine innervates the lacrimal gland to stimulate aqueous secretion.
Which of the following is the primary contributor to iris color?
D. Anterior border layer is the primary contributor to eye color with trace input from the iris stroma.
Which of the following lens nuclei is demarcated by sutures?
B: Fetal nucleus is the only site of Y-sutures. The embryonic nucleus contains the most mature fibers.
Which Cranial Nerve is at highest risk for damage due to trauma?
D: CN IV, the trochlear nerve as it is not only the thinnest nerve, it also has the longest course of all cranial nerves as it leaves the brainstem dorsally.
Which of the following statements regarding CN IV is INCORRECT?
C: Innervates the SUPERIOR oblique; all other statements are correct.
Which of the following pairs of parasympathetic cranial nerves and associated ganglion is INCORRECT?
E. All of the above are correct. It is important to understand the general pathways innervation travels to the orbit and adnexa. Try to draw out these pathways with blanks that you can fill in and erase later.
Which of the following represents remnants of the hyaloid artery on the optic nerve?
E. Bergmeister’s Papillae can remain at the optic nerve. Mitterndorf and Epicapsular star are lens findings. Cloquet’s canal is within the vitreous. Weiss ring is the consequence of a posterior vitreous detachment of the optic nerve.
Which of the following allows for lateral movement of the globe?
C. Plica Semilunaris allows for movement WITHIN the globe. The fornix and caruncle are location and redundant tissue, respectively. Mueller’s is responsible for lifting the eyelid. The muscle of riolan is responsible for keeping the eyelid adhered to the globe.
Which of the following statements describing the lateral rectus is CORRECT? (PICK 3)
A, B, D: The lateral rectus is unique in that it is the only nerve innervated by CN VI. Nerve innervation begins in the pons and travels past the precarious skull process which is more susceptible to damage from increased cranial pressure (vs. trauma). Unlike the other extraocular muscles, the lateral rectus has two origins on the annulus of zinn and receives blood supply from only one artery.
Which of the following muscles causes extortion, abduction, and/or elevation?
B. Recall that torsion is a primary function of obliques; OBliques ABduct (or O’s to the nose); and obliques have opposite roles in supraduction.
The central retinal artery forms two capillary networks within the ____ and _____.
B. The CRA has networks within both the Nerve Fiber Layer and the Inner Nuclear Layer. Dot and blot hemes are seen in the OPL as bleeding from INL leaks down layers.
Which of the following retinal layers contains the cell bodies of the photoreceptors?
C. The outer nuclear layer in the retina contains all the cell bodies of the photoreceptors.
What is the opsin found in iprGCs?
A: Melanopsin is found in the intrinsically photosensitive ganglion cells. These cells are thought to be regulators of the circadian rhythms found in mammals.
Which vitamin is responsible for generation and health of retinal photopigments?
A. Vitamin A is the main component of opsins. Vitamin B can be found in all cells and usually depleted in alcoholics. Vitamin C is important in collagen synthesis, antioxidants, wound healing, bone formation, and many other functions. Vitamin D is supplied by the sun and helps in digestion. Vitamin E is an antioxidant found in vapes that in conjunction with nicotine, can increase the likelihood of developing cancer.
Which of the following is NOT part of the uvea?
B. The uvea is made up of iris, ciliary body, and the choroid.
Which layer of the eye is located between the conjunctival stroma and episclera?
B: Tenon’s capsule – To remember, consider C.C. TESLA From anterior to posterior: C. epithelium, C. stroma, Tenon’s capsule, Episclera, Scleral proper, Lamina fusca, and Anterior choroid
What type of connective cell is responsible for the blood/aqueous barrier?
C. Zonula Occludens/Adherens are responsible for tight barriers. Desmosomes maintain structure integrity. Hemidesmosomes are responsible for connecting cells to their basement membranes. Gap junctions serve a role in small ion transport and cell-cell signalling. Keratocytes are cells responsible for structural integrity of the cornea.
Which region of the ciliary body do the lens zonules begin their course from?
B. The lens zonules begin their course from the pars plana and traverse to the posterior lens capsule to participate in accommodation.
Which of the following is NOT considered a side effect of Tamoxifen?
E. All of the above traits are true. To recall, the 4 C’s of side effects: Clots, Cancer, Crystal, Corneal Whorl. Tamoxifen inhibits estradiol thereby reducing estrogen effects in the breast. Patients in remission must remain on this medication for up to 5 years after successful treatment.
Which of the following medications is commonly used in the treatment of muscle spasms?
C. Cyclobenzaprine, also known as Flexeril, is a muscle relaxant used in treatment of muscle spasms. It works by decreasing somatic motor activity by inhibiting tonic activity of alpha and gamma neurons. Caution as this medication may cause Narrow Angle Glaucoma.
Which of the following is associated with superior limbic keratoconjunctivitis? (PICK 3)
B,C,E: Superior limbic keratoconjunctivitis (SLK) is related to FRICTION. Dry eye, thyroid eye disease, and contact lens hypersensitivity are most commonly associated with SLK.
One would expect to see preauricular adenopathy (PAN) in all of the following, except:
C. Ligneous conjunctivitis is caused by a systemic plasmin deficiency leading to development of thick mucous membranes. Other conditions associated with PAN include viral, inflammatory systemic, and hyperacute bacterial infections.
With regards to keratoconus, which of the following is NOT an associated systemic condition?
B. Klinefelter syndrome is NOT associated with keratoconus. To recall these conditions, use the mnemonic “T-DOME”: Turner Syndrome, Down Syndrome (aka Trisomy 21), Osteogenesis Imperfecta (aka Brittle Bone disease), Marfan Syndrome, and/or Ehlers-Danlos Syndrome. Other lower yield conditions include atopic dermatitis (excessive rubbing) and mitral valve prolapse (can be correlated to Marfan syndrome).
Which slit lamp technique is best for evaluation of non-opaque corneal lesions?
E. Indirect illumination is used to assess non-opaque corneal lesions by focusing oculars adjacent to the beam of light (i.e EMBD). Sclerotic scatter is used to evaluate the clarity of the cornea. Optic section is used to determine depth (i.e. Van Herick, corneal scar). Conical beam is used to assess anterior chamber for cells and flare. Specular reflection is used to assess the corneal endothelial cells (i.e. Fuchs).
Of the following test results, which are indicative for dry eye? (PICK 3)
A,D,E: A normal result for phenol red thread test is >10mm in 15 secs, Schirmer 1 test is >10mm in 5 minutes, Schirmer 2 testing (with anesthesia) is >5mm in 5 minutes. Tear osmolarity should be greater than 308 mOsm/L. Tear meniscus is measured under a slit lamp and should be greater than 0.2mm. Tear break up time (TBUT) is evaluated under slit lamp and blue light conditions. The tear film should remain intact for up to 10 secs.
A diabetic patient presents to the office without complaint. Slit lamp examination reveals diffuse punctate erosions with an area of ulceration. Damage to which cranial nerves leads to development of Neurotrophic Keratopathy? (PICK 2)
A,E: Either the nasociliary branch of the trigeminal (V1) and/or the facial nerve (VII). The nasociliary nerve is responsible for sensory information from the cornea. Corneal regeneration is reduced as there is little feedback from the corneal nerves that indicate damage. Common causes of damage include HSV, DM, LASIK, contact lens overwear, and chronic corneal injury. The facial nerve can also cause NK due to reduced reflex tearing and inability to close the eyelid leading to chronic damage of ocular surface and further damage to VI. The cotton-swab test is used for aid in diagnosis of NK.
What is the minimal number of endothelial cells/mm2 required to prevent corneal edema?
B. The minimum number is 400-700 cells/mm2. This range is seen in older patients or those diagnosed with Fuchs’ endothelial dystrophy. From birth, the average range is 3,000-4,000. After 80, that number drops to about 1,000-2,00 cells. Recall that endothelial cells do not regenerate.
Which of the following conditions would you expect to present with unilateral cells in the anterior chamber with acutely elevated IOP?
A,C,D: These conditions lead to development of trabeculitis and iritis that reduces aqueous outflow. This reduction in outflow leads to spikes in IOP as high as the 40s-50s. Sarcoidosis may cause inflammation anywhere in the body. Most often, Sarcoidosis leads to bilateral uveitis and may also include posterior or panuveitis. Toxoplasmosis does not often cause anterior uveitis, rather posterior or panuveitis.
Which of the following conditions would you expect to find stellate KPs?
C,D: Stellate KPs are unique to Herpes simplex and Fuch’s iridocyclitis. Other options listed here are also considered granulomatous. However, these conditions present with Koeppe (found at pupillary margin) or Busacca nodules (other locations on iris).
What is the most common cause of unilateral glaucoma?
A. Trauma is the number 1 cause of unilateral glaucoma. This is due to damage to the TM when the iris root is affected.
A patient presents with complaints of one eye looking smaller than the other with pain and redness of the upper eyelid. You note an S-shaped ptosis of the same eye. Which of the following is most likely to cause this clinical finding?
A. An S-shaped ptosis is classically associated with dacryoadenitis – inflammation of the lacrimal gland. Dacryoadenitis can occur acutely or chronically. Acute infections present with S-shaped ptosis, pain, redness, and preauricular lymphadenopathy. Acute infections are often bacterial or viral in nature. Chronic infections have a similar set of signs/symptoms, however, to a much lesser degree. Chronic infections are related to inflammatory disorders such as the other answer choices.
A patient presents with a mild ptosis, miosis, and anhidrosis. You correctly diagnose Horner’s syndrome. Which ocular muscle has been affected leading to the lower eyelid?
B. Mueller’s muscle is the culprit. Horner’s is known to affect the sympathetic nervous system. Mueller’s muscle is innervated by sympathetic input and acts to lift the eyelid 2-3mm. This is the reason for the mild ptosis in Horner’s patients.
Which cranial nerve is responsible for eyelid elevation while chewing in a patient with Marcus Gunn Jaw Winking syndrome?
B. A consequence of congenital aberrant degeneration, the motor branches of the trigeminal nerves will simultaneously communicate with the superior division of the oculomotor nerve which controls the levator.
What pathogen is the most common cause of blepharitis?
E. Although staph epidermidis is a common cause, Staph Aureus is seen most frequently. H. influenza and N. gonorrhoeae are gram “-” bacteria more common in children’s bacterial eye infections. Moraxella is more common in angular blepharitis.
A patient presents to your office with complaints of yellow plaques growing on the skin below their eyes. Blood work should reveal elevated levels of __________.
D. Cholesterol. The condition we are seeing is known as Xanthelasma. The yellow plaques develop over time with elevated cholesterol levels. The patient can be referred for excision/cryotherapy after cholesterol levels are brought back to normal levels.
What is the most common cause of orbital cellulitis in children?
D. H. influenzae is the most common culprit for cellulitis in children. Staph aureus is the most common cause of cellulitis in adults.
Which of the following represents the correct order in which EOMs are affected in Thyroid Eye disease?
C. The correct order is Inferior rectus, Medial rectus, Superior rectus, Lateral rectus, and then the obliques. The mnemonic for this condition is “IM SLO”.
Which of the following terms correctly describes whitening of the eyelashes?
B. Poliosis is the whitening of eyelashes often caused by chronic eye infections. Madarosis describes a loss of eyelashes. Tylosis is thickening of the lid margin. Trichiasis is an inward turned eyelash. Sudoriferous is a term used to describe a cyst.
Which of the following chemical agents is most dangerous to the eye?
D. Chemical burns with alkali agents are more dangerous than acidic agents. This list is challenging. First, remove the two acids. Next, we know that fertilizers and pepper spray (PAVA) are both acidic. Calcium hydroxide is not only basic, but also the most common cause of alkali burns.
During ocular development, the optic vesicles interact with which of the following tissues?
C. Surface Ectoderm. Embryonic optic vesicles form as an extension of the neural tube. As these approach the surface ectoderm, the lens placide and lens vesicles form. The narrow cleft, aka embryonic fissure, forms in the walls of the optic cup. Hyaloid vessels form the vascular capsule of the lens.
You are conducting a 4BO test on a suspected microstrabismus. You place the loose prism in front of the right eye and note an outward movement of the left eye that does NOT refixate. What is your conclusion?
C. Suppression of the left eye. Placing a loose 4BO in front of the right eye causes a small movement of the right eye toward the apex of the prism. Due to yoked muscles movement, the left eye will also move. If the left eye is not suppressing, it should quickly re-fixated to target. If there is NO movement of either eye with lens placement, it is a suppression of the right eye. If the left eye does not refixate after a right eye shift, the left eye is considered suppressed.
By the age of ____, a child should be able to draw and identify a square?
E, 4.5 years is roughly when a child should be able to draw and identify a square. Some important shapes to know include: Straight line near the end of 2 years of age, Circle at 3 years, and Triangle near 5 years.
Accommodation reaches adult levels by ______ of age.
A. Accommodative response is present at birth and reaches maturity at about 3 months of age. It is important to review key ocular motor and visual development milestones.
Which of the following statements regarding fusional vergence is FALSE?
C. Minus lenses indirectly test NEGATIVE fusional vergence. Adding minus lenses increases accommodation and convergence. In order to maintain images on the fovea,negative fusional vergence is required to overcome the changes. Prisms directly test the direction of their apex.
Which of the following conditions is an adverse effect of Tamsulosin?
B. Floppy iris syndrome is an adverse effect of Benign Prostatic Hypertrophy – a condition that causes frequent but poor urination. It is important to remember this medication as Floppy Iris Syndrome can impact cataract surgery. Tamsulosin is considered an Alpha-1 blocker.
Which of the following medications are known to cause retinal pigmentary changes? (PICK 3)
A/B/C: These three medications may cause retinal pigmentary changes. When it comes to pigmentary changes throughout the eye, the drug class Phenothiazines (antipsychotics) are infamous for this adverse effect. From pigment on endothelium to the retina, the “-Azines” affect all regions of the eye.
All of the following are the most clinically significant side effects of chronic corticosteroid use, EXCEPT?
C. Chronic corticosteroid use leads to development of posterior SUBCAPSULAR cataracts. PCO develops after a PCIOL has been in an eye for a period of time. The remaining options are correct facts.
Which of the following steroids are LEAST likely to cause an elevation in intraocular pressure?
B. Loteprednol is considered the safest steroid for prescribing. Unfortunately, many cases of inflammation are severe and require stronger prescription steroids. In these cases, it is important to educate patients about proper use and follow up schedules to avoid rebound inflammation.
All of the following are Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), EXCEPT:
E. Cromolyn Sodium is classified as a mast cell stabilizer. The remaining options are NSAIDs. Recall that “-fenac” and “-rolac” help identify generic equivalents.
All of the following medications may cause Verticillata, EXCEPT:
E. Voltaren is not known to cause Whorl Keratopathy (aka Verticillata). Recall, CHAI-T when asked about verticillata. Do not forget, Fabry’s Disease may also lead to this finding.
Which of the following increases risk of developing Bull’s Eye Maculopathy with chronic use of Hydroxychloroquine?
B. Abnormal renal function can cause an increased risk of developing side effects related to chronic use. To recall: treatment duration greater than 5 years, abnormal renal function, high body fat percentage, over 60 years of age, and/or liver disease can increase risk of BEM.
Of the following drugs, which one works by a dual mechanism of histamine inhibition and mast cell stabilizers?
A. Optivar is the only allergy eye drop listed here that is a combination of H1 inhibition and stabilization of mast cells. Mast cells stabilizers work by preventing Ca2+ from binding mast cells. Calcium serves to initiate degranulation of mast cells leading to allergy symptoms. Recall, BEZPOP for combination antihistamines.
Which of the following is NOT considered a mast cell stabilizer?
B. Emadine is considered only an antihistamine with no mast cell stabilizer action. The remaining choices all work by preventing mast cell degranulation by preventing binding of Ca2+.
All of the following are possible side effects of Tetracyclines, EXCEPT:
C. Ototoxicity is not considered a side effect of Tetracyclines. Tetracyclines function by inhibiting protein synthesis through binding of 30s subunits of bacterial ribosomes.
What is the mechanism of action of Tropicamide?
B. Tropicamide, a cholinergic antagonist, works by preventing binding of acetylcholine at muscarinic sites. Direct stimulation of cholinergic receptors is the MOA for Pilocarpine. Anesthetics act by preventing influx of Na+ ions.
All of the following are possible side effects of Pilocarpine, EXCEPT:
B. Use of Pilocarpine may cause a MYOPIC shift. Other side effects include: brow aches, headaches, miosis, cataracts, retinal detachment, and secondary angle closure.
Which of the following adrenergic agonists acts specifically on ⍺1 receptors?
C. Phenylephrine is an adrenergic agonists that acts only on ⍺1. Brimonidine is highly selective for ⍺2 and Apraclonidine acts on ⍺2 receptors with limited ⍺1 activity. Naphazoline and Tetrahydrolozine are non-specific alpha receptor agonists.
Pilocarpine is used to confirm diagnosis of which of the following conditions?
C. Adie’s Tonic Pupil. Since the iris sphincter is desensitized in Adie’s, it will respond to even a low concentration of pilocarpine. Recall that ADie’s is an Acutely Dilated pupil normally found in young females.
All of the following are contraindications of prostaglandin analogs, EXCEPT:
E. Grave’s disease is not considered a contraindication for PG use. The remaining options describe conditions associated with inflammation. Recall that PGs are produced naturally in response to inflammation in the body.
Which of the following topical drop preservatives is used in the treatment of Band Keratopathy?
C. EDTA is a Calcium ion chelating agent that can be used in treatment of Gout and Band Keratopathy. BAK is infamous for causing SPK with the benefit of increased corneal penetration. Thimerosal is considered very toxic as it contains mercury. SP is found in artificial tears/ointment and is considered less toxic.
All topical anesthetics are categorized as ______
C. All topical anesthetics are considered esters for their shorter duration and ability to be metabolized locally. Amides have a longer duration and are metabolized by the LIVER.
Which of the following will increase production of aqueous humor? (PICK 3)
A,B,C. All of these options will influence pars plicata to produce more aqueous humor. Build up of H+ in pigmented epithelium leads to reversal of bicarbonate ion movement, thus halting aqueous production. A similar mechanism can be seen with increased intracellular Cl- ions.
By which method is a majority of aqueous humor produced?
C. Active secretion is responsible for 80-90% of aqueous humor production. A small portion of aqueous is produced through diffusion and ultrafiltration. Hydration and holocrine are both distractors.
Which of the following allows for adherence of the mucus layer to the corneal epithelium?
D. Glycocalyx, which is secreted by the epithelial cells, allows adherence of the mucus layer. Goblet cells secrete mucins which make up the mucus layer.
Which of the following statements about corneal nerves is INCORRECT?
B. The long ciliary nerves of the cornea are branches of the ophthalmic division of the trigeminal nerves (CN V). The nerves enter into the cornea and traverse about ⅔ of the distance before moving anteriorly. These nerves loes myelin sheath about 1.5mm into the cornea.
Which gland within the sympathetic pathway does NOT synapse with a ganglion?
D. The adrenal gland does not have a ganglion synapse with the ganglionic fibers of the spinal column. Rather, it receives a signal to release epinephrine directly into the bloodstream.
All of the following are found in the tear film, EXCEPT:
C. All but Vitamin B are found in the tear film. Lysozymes serve as bacteriolytic cells. Defensins and IgA serve to detect foreign material and cells. Lactoferrin protects the eye from free radical iron molecules.
A corneal topographic map shows a “Figure 8” pattern with noted horizontal steepening. What does this represent?
D. This CT pattern is indicative of against-the-rule astigmatism. WTR astigmatism is characterized by a bow tie pattern with vertical steepening. Keratoconus would present with inferior steepening. Pellucid marginal degeneration scans are known for a kissing dove or crab claw appearance.
A patient looks 4 mm to the right in a +2.00 D lens over the right eye. What is the resulting power and direction of the prism induced?
D. Total prism induced is 0.8 BI. First, recall Prentice’s law (Total prism = power of lens x decentration in centimeters). In this example, the answer is 0.8. Next, draw a picture of the lens (two triangles sharing one side). We can see that the patient is looking through the base-in portion of the lens.
A patient’s pupillary distance (PD) is measured at 70 mm. The patient is fit into a frame with a PD of 74 mm. How much and in what direction must the right lens be decentered to fit correctly?
D. The lens will need to be moved 2 mm to place the optical center in front of the patient’s eye. Do not forget that TOTAL decentration is 4 mm but each lens only moves half of that. Easy rule of thumb – patient PD < frame PD = move lens in and vice versa
A patient presents with acute angle closure glaucoma. You are able to reduce intraocular pressure in the office and refer for laser peripheral iridotomy. What type of laser is most commonly used in this procedure?
C. YAG laser is used for LPI, PCO, and SLT. Argon and Krypton are used for PRP, ALT, retinal tears, and in rare instances LPIs. Excimer/LASIK laser is used for LASIK and PRK. Helium neon is used to illuminate the retina to view the fundus.
Fluorescein examination of a spherical GP lens demonstrates a bow-tie pattern of lens touch and figure-8 pattern of lens clearance. What type of corneal shape does this patient have?
A. This pattern is classic for WTR astigmatism. The opposite pattern of clearance and touch indicates ATR. General clearance or touch is more characteristic of a spherical cornea. You would expect an inferior spot of lens touch.
Silicone hydrogel contact lenses are designed for better oxygen transmission. What occurs to the transmission levels as one decreases the water content of the lens?
D. Increased oxygen transmission via silicone as the water content decreases. Increasing water content leads to lower ratio of Silicone to water. Therefore, more water in the lens means less oxygen from tears through the silicone.
What is the minimum amount of clearance over the cornea for a fully-settled scleral lens?
C. The minimum amount of clearance is 50 microns. In practice, it is best to aim for 100-150 but 50 microns will still allow for corneal clearance even with blinks.
A low vision patient presents with an initial BCVA of 20/500 in both eyes. How would you classify their vision?
D. 20/500 is considered Profound low vision. Recall the following pairs: Normal = 20/12 -20/25, Near-Normal = 20/30 to 20/60, Moderate = 20/70 – 20/160, Severe = 20/200 – 20/400, Profound = 20/500 – 20/1000, Near Blindness > 20/2000. Blindness is no perception of light or motion.
What is the effective magnification of a 20 D magnifier held at standard distance?
C. 5x. Recall the equation Effective magnification = F/4 = 20/4. Standard distance is 25 cm as the standard presbyopic and emmetropic patient needs a +4.00 add for magnification.
Which of the following conditions can arise in a patient diagnosed with AIDS with concurrent HHV-8 infection?
B. Kaposi’s sarcoma is a malignant lesion that develops secondary to an active herpes infection in an immunocompromised individual. The remaining options are all opportunistic infections that develop as CD4 cell count declines.
Which of the following statements about Systemic Lupus Erythematosus (SLE) is FALSE?
A. SLE is an example of a Type III hypersensitivity reaction – involves ag/ab complexes. SLE most often presents in young women in their teens and twenties. These patients may experience a malar rash, joint pain, and other consequences of inflammation in the body. Blood work will reveal a positive ANA.
Which of the following vitamins is used as a supplement to reduce the probability of developing Spina Bifida?
C. Folic acid supplementation can significantly reduce the risk of spina bifida in a newborn. Spina bifida is a defective closure of the spinal cord that leads to lower body dysfunction and decreased mental function.
Which of the following is NOT associated with epicanthal folds?
C. Klinfelter syndrome is the only option in this list without evidence of prominent epicanthal folds. Be sure to know other conditions besides Down syndrome and Fetal Alcohol syndrome. Blepharophimosis is an eyelid condition that demonstrates REVERSE epicanthal folds.
An acute, recurrent hypopyon in a young South Asian man is most likely associated with which inflammatory disease?
D. Behcet’s disease is an inflammatory disease that occurs more commonly in young males of Middle Eastern or Asian descent. It is defined as recurrent mouth, eye and/or genital sores. One must have two of these to receive a formal diagnosis. Behcet’s is associated with acute recurrent hypopyon as well as all forms of uveitis.
A 55yo Caucasian female presents with complaints of jaw pain while eating and scalp tenderness. Patient reports sudden loss of vision of the eye on the same side. Which of the following blood work results would you NOT expect?
A. An ESR of 30 mm/hr is considered normal in a female of this age. This patient suffers from Giant Cell Arteritis. Abnormal GCA results include: elevated ESR, CRP, and platelet count as well as inflammation of the temporal artery noted on biopsy. Recall that elevated ESR in males is greater than their age divided by 2 (> age/2) and in females it is their age plus ten (> (age+10)/2). Elevated CRP is considered greater than 2.45 mg/dL. Elevated platelet count is any value > 400,000.
_________ states that critical diameter of light varies with eccentricity and retinal illumination.
A. Ricco’s law states that the number of photons is the same for all stimulus sizes that are less than a critical diameter. This varies as stated above. Bloch’s law describes a critical time threshold for stimulation. Ferry-Porter law states the critical flicker frequency with the log of retinal illumination. Granit-Harper law states that the CFF increases as the stimulus area increases.