Free COT® Practice Test: Sample Questions with Answers

1. Question 1

   An exophthalmometry result is charted as "Hertel base 102, OD 21 mm, OS 24 mm." The base figure is recorded because it:

   1. A. Names the model of instrument that was used, so that a clinic holding several exophthalmometers can match each reading to the device that produced it
   2. B. Documents the distance from the instrument's mirrors to the examiner's eye, which is what the parallax reference lines are used to set
   3. C. Converts the millimeter readings into a percentage of the normal protrusion expected for the patient's age and ethnic background before charting
   4. D. Is the millimeter separation of the footplates on the lateral orbital rims for this patient, so readings taken at a different base are not comparable
   Show answer to question 1

   Answer: D. Is the millimeter separation of the footplates on the lateral orbital rims for this patient, so readings taken at a different base are not comparable

   The Hertel measures each cornea's forward position relative to the lateral orbital rims, so the rim-to-rim separation is part of the measurement setup. Widen or narrow the base and the reference points move, changing the numbers even though the orbit has not. Serial measurements only mean something when base, instrument and technique are held constant, which is why the base is charted every single time and repeated by the next examiner.

2. Question 2

   A dry-eye workup calls for tear osmolarity, tear break-up time, ocular surface staining and Schirmer testing at one visit. The correct order is:

   1. A. Schirmer, staining, tear break-up time, osmolarity — most invasive first, so the strip provokes the tearing the later tests need
   2. B. Osmolarity, tear break-up time, staining, Schirmer — least invasive first, because each test disturbs the film for the ones that follow
   3. C. Staining, osmolarity, Schirmer, tear break-up time — dye first, because fluorescein must be given time to work before anything is measured
   4. D. Any order at all, provided that all four are completed at the same visit and each is charted with the time it was performed
   Show answer to question 2

   Answer: B. Osmolarity, tear break-up time, staining, Schirmer — least invasive first, because each test disturbs the film for the ones that follow

   Osmolarity samples the undisturbed tear film and is invalidated by any prior drop, so it goes first. Break-up time needs fluorescein but no anesthetic. Staining is graded after the dye has had time to work. Schirmer comes last because the strip abrades the surface and provokes reflex tearing that would corrupt every other measurement. Reversing the sequence is the classic way to generate four numbers that contradict both each other and the patient's symptoms.

3. Question 3

   The Farnsworth-Munsell 100-hue test is chosen over the D-15 when the clinic needs to:

   1. A. Test a patient who cannot reliably arrange caps in order, since the 100-hue offers a simplified forced-choice format instead
   2. B. Grade severity quantitatively and follow a color defect over time, since the caps yield a total error score plotted by hue
   3. C. Screen a waiting room quickly, because the four trays can be sorted in about a minute once the first cap has been shown
   4. D. Detect blue-yellow defects at all, since the D-15 contains only red-green caps and cannot reveal a tritan arrangement
   Show answer to question 3

   Answer: B. Grade severity quantitatively and follow a color defect over time, since the caps yield a total error score plotted by hue

   The 100-hue uses 85 movable caps in four trays and produces a numeric total error score with a polar plot, so serial testing can document a toxic or nutritional defect worsening or recovering. The cost is time: it is far slower than the D-15 and demands sustained attention, which is exactly why it is a poor choice for an uncooperative patient or a screening line. The D-15 does detect tritan defects; it simply cannot grade them finely.

Supplemental Skills study guide →

1. Question 4

   Counseling a patient immediately before intravenous fluorescein angiography, the technician should explain that:

   1. A. The dye is mildly radioactive, so close contact with young children should be limited for a full day
   2. B. The skin may look yellow for a few hours, the urine will be discolored, and brief nausea is common
   3. C. The yellow tint the patient sees will last for several days before color perception returns to normal
   4. D. The dye is injected into the eye itself with a fine needle after a drop of topical anesthetic
   Show answer to question 4

   Answer: B. The skin may look yellow for a few hours, the urine will be discolored, and brief nausea is common

   Sodium fluorescein is injected into an arm vein, not the eye, and is not radioactive. Expected effects are transient skin yellowing for several hours, bright discolored urine for about 24–36 hours, and a wave of nausea in the first minute or two. Setting that expectation prevents panic; the patient is separately told to report itching, hives, or any breathing difficulty at once, because those signal a true allergic reaction rather than an expected effect.

2. Question 5

   A low-vision patient's best-corrected distance acuity is 20/200. Using Kestenbaum's rule as a starting point, the near add to try first for reading 1 M print is approximately:

   1. A. +2.50 D
   2. B. +5.00 D
   3. C. +10.00 D
   4. D. +20.00 D
   Show answer to question 5

   Answer: C. +10.00 D

   Kestenbaum's rule takes the reciprocal of the distance acuity fraction as the dioptric add: 20/200 inverts to 200/20, which is 10, so a +10.00 D add is the starting lens. The patient reads at the focal distance of that add — about 10 cm. It is an estimate to begin trial-frame testing, not a prescription; the final power is settled by what the patient can actually read comfortably.

Ophthalmic Patient Services and Education study guide →

1. Question 6

   Partway through a fluorescein injection the patient reports burning at the injection site and a firm swelling appears beneath the skin. The technician should:

   1. A. Stop the injection at once, notify the physician, and elevate and cool the arm
   2. B. Inject the remainder quickly so the transit phases can still be photographed
   3. C. Continue the injection, since fluorescein in the tissue causes no lasting harm
   4. D. Massage the site vigorously to disperse the dye, then finish the remaining injection
   Show answer to question 6

   Answer: A. Stop the injection at once, notify the physician, and elevate and cool the arm

   Firm swelling with burning means the dye is going into tissue rather than vein. Extravasated fluorescein is intensely irritating and can cause severe local pain and, with larger volumes, tissue injury and sloughing, so every additional milliliter makes the injury worse — and vigorous massage simply spreads the irritant through more tissue. Stop, elevate, cool, tell the physician, and document. Prevention is the real lesson: confirm blood return and free flow before injecting, choose an adequate vein, and secure the line.

2. Question 7

   A follow-up macular cube on a patient with an epiretinal membrane reports a central subfield thickness of 612 μm, far above the prior visit. On the B-scans the inner boundary line has been drawn along the posterior hyaloid rather than the internal limiting membrane. The technician should:

   1. A. Report the 612 μm figure exactly as measured, since the software output is the standard of record for the visit
   2. B. Recognize the segmentation error, correct or flag it, and have the physician see the raw B-scans
   3. C. Delete the study and record that no interpretable OCT was obtainable at this visit
   4. D. Switch the analysis to the myopic normative database so the boundary lines are redrawn
   Show answer to question 7

   Answer: B. Recognize the segmentation error, correct or flag it, and have the physician see the raw B-scans

   A thickness map is only as trustworthy as the boundary lines the software drew, and membranes, large pigment epithelial detachments, dense fluid and low signal all push segmentation astray. An uncorrected error can manufacture apparent worsening and drive an unnecessary injection, or hide real fluid. Most devices allow manual correction or a rescan; at minimum the error is flagged. Deleting the study discards genuine information, and the normative database governs color coding, not segmentation.

Ophthalmic Imaging study guide →

1. Question 8

   On a fogged astigmatic (clock) dial the patient reports that the 2–8 o'clock line is blackest and sharpest. The axis of the correcting MINUS cylinder is:

   1. A. 30
   2. B. 60
   3. C. 90
   4. D. 120
   Show answer to question 8

   Answer: B. 60

   The rule of 30: multiply the lower clock-hour of the clearest line by 30. Here 2 × 30 = 60, so minus cylinder is added at axis 60 until every spoke of the dial looks equally black. Axis 30 would follow from the 1 o'clock line, 90 from 3 o'clock, and 120 from 4 o'clock. The dial only works while the patient is fogged, so the interval lies in front of the retina.

2. Question 9

   During JCC power refinement you add −0.50 D of cylinder. To keep the circle of least confusion on the retina you should at the same time:

   1. A. Add −0.50 D of sphere
   2. B. Add +0.25 D of sphere
   3. C. Add +0.50 D of sphere
   4. D. Leave the sphere alone until refinement is finished
   Show answer to question 9

   Answer: B. Add +0.25 D of sphere

   Spherical equivalent is sphere plus half the cylinder, so every −0.50 D of minus cylinder drags the equivalent 0.25 D minus-ward. Adding +0.25 D of sphere holds it constant and keeps the blur circle centered on the retina. Neglecting the compensation lets the sphere drift minus as cylinder accumulates, and a young patient will accommodate to clear it — corrupting the endpoint you are trying to find.

Refractometry study guide →

1. Question 10

   A patient reports seeing double. The single most useful question to ask next, and the reason it comes first, is:

   1. A. "Have you ever had eye surgery?" — because surgical history determines whether diplopia is possible
   2. B. "Does the double vision go away when you cover either eye?" — because this one question sorts binocular from monocular diplopia before any measurement is taken
   3. C. "Is the second image in color?" — because colored second images indicate a neurologic cause
   4. D. "Is the second image beside, above or below the first, and does it stay separated the same way in every direction of gaze?" — because the pattern of separation identifies the affected muscle
   Show answer to question 10

   Answer: B. "Does the double vision go away when you cover either eye?" — because this one question sorts binocular from monocular diplopia before any measurement is taken

   The monocular/binocular split is the first fork in the entire diplopia workup and it costs one question. Binocular diplopia resolves when EITHER eye is occluded and means the two eyes are not aligned — cranial nerve palsy, restriction, decompensated phoria. Monocular diplopia persists in the affected eye with the fellow eye covered and is optical: uncorrected astigmatism, cataract, an irregular tear film, keratoconus, posterior capsular opacity or a decentered implant. Answering this before any measurement tells the physician which examination they are about to do.

2. Question 11

   A parent reports that their four-month-old has watery eyes, squeezes them shut in bright light, and "one eye looks bigger than the other." The technician should recognize this history as:

   1. A. Ordinary neonatal tearing needing no more than routine lid hygiene instructions at home
   2. B. A normal developmental stage in which most otherwise-healthy infants simply dislike bright light until about six months of age or so
   3. C. An allergic response best managed by an over-the-counter antihistamine eye drop
   4. D. The classic triad of epiphora, photophobia and blepharospasm, which with an enlarged eye raises concern for congenital glaucoma
   Show answer to question 11

   Answer: D. The classic triad of epiphora, photophobia and blepharospasm, which with an enlarged eye raises concern for congenital glaucoma

   Epiphora, photophobia and blepharospasm together are the textbook presentation of congenital (infantile) glaucoma, and an enlarged or hazy-looking cornea — buphthalmos from a distensible infant eye — makes the picture much more worrying. Simple nasolacrimal duct obstruction causes tearing and mattering of the lashes but not photophobia, blepharospasm, or an enlarging, hazy cornea. The technician's role is to recognize that this specific combination is not routine infant tearing and to escalate it the same visit, not to diagnose or to recommend a drop.

History Taking study guide →

1. Question 12

   On a standard phacoemulsification footpedal, position 2 delivers:

   1. A. Irrigation plus aspiration
   2. B. Irrigation only
   3. C. Irrigation, aspiration, and ultrasound together
   4. D. Ultrasound only, with irrigation controlled separately
   Show answer to question 12

   Answer: A. Irrigation plus aspiration

   The ladder is cumulative: position 1 opens irrigation, position 2 adds aspiration, position 3 adds ultrasound power. Knowing it converts a vague complaint into a located fault. If the surgeon reports no vacuum in position 2, the problem lies in the aspiration path — a clamped line, a poorly seated cassette, an occluded tip. If the chamber shallows in position 1, the fault is on the irrigation side — bottle height, a closed clamp, an empty bottle. Position 3 adds ultrasound on top of irrigation and aspiration, so a complaint that appears only in position 3 localizes to the handpiece connection, the tip, tuning, or a power setting left at zero.

2. Question 13

   Two unlabeled syringes and a medicine cup of clear fluid are sitting on the sterile back table. The correct action is to:

   1. A. Keep them, since only one drug is being used on this case and the vial is still in the room
   2. B. Label them at the end of the case, while the vials are still available for checking
   3. C. Discard them and start over, then label each new solution at the moment it is transferred
   4. D. Identify the contents by appearance and odor, then label each one with name and strength
   Show answer to question 13

   Answer: C. Discard them and start over, then label each new solution at the moment it is transferred

   Wrong-drug and wrong-concentration events on the ophthalmic sterile field are well documented, because clear, similar-looking solutions — balanced salt solution, lidocaine, epinephrine dilutions, antibiotics — sit inches apart, and a fraction of a milliliter of the wrong one in the anterior chamber can be blinding. The rule is absolute: label at the moment of transfer, confirm drug and dilution aloud with the circulator against the vial, and discard anything unlabeled or of uncertain identity. Waiting until the end of the case labels from memory, and identifying a drug by look or smell is not identification at all.

Assisting in Surgical Procedures study guide →

1. Question 14

   A patient with a dense central posterior subcapsular cataract reads 20/70; with a pinhole the acuity drops to 20/100. The best explanation is:

   1. A. The pinhole sent every ray through the axial opacity and cut retinal illumination
   2. B. The cataract caused a myopic shift too large for the pinhole to neutralize
   3. C. The habitual and pinhole acuities were transposed when the two results were charted
   4. D. The patient tired from reading the same chart twice in quick succession
   Show answer to question 14

   Answer: A. The pinhole sent every ray through the axial opacity and cut retinal illumination

   A posterior subcapsular opacity sits directly on the visual axis, so a pinhole forces every ray through the worst part of the lens while also cutting total light. Pinhole worsening is a meaningful finding pointing toward axial media opacity rather than refractive error, and it should be recorded rather than repeated until it improves. Uncorrected refractive error, including a myopic shift from cataract, is what a pinhole improves: even an error too large for the pinhole to correct fully still blurs less through it, not more, so it cannot explain acuity that falls. A myopic shift is also more typical of nuclear sclerosis than of a posterior subcapsular cataract. Blaming fatigue or a transposed entry throws away a real finding.

2. Question 15

   A wall chart calibrated for 20 feet is read in a 12-foot lane with no rescaling or mirror. The patient reads the line labeled 20/30. The acuity actually demonstrated is:

   1. A. 20/18
   2. B. 20/30
   3. C. 20/50
   4. D. 20/72
   Show answer to question 15

   Answer: C. 20/50

   Record what was really done: 12/30. Multiply top and bottom by 20/12 to put it on the 20-foot scale: 12/30 = 20/50. At 12 feet every optotype subtends 20/12 = 1.67 times its intended angle, so the patient is performing that much worse than the printed label suggests. An uncalibrated short lane flatters every patient in the clinic and corrupts comparison with any correctly calibrated lane.

Visual Assessment study guide →

1. Question 16

   Among homonymous hemianopias, the MOST congruous defects — the two eyes' defects nearly identical in shape — arise from lesions located:

   1. A. In the occipital cortex, where the optic radiations end
   2. B. In the temporal lobe, where the radiations loop forward
   3. C. In the optic tract, just behind the chiasm
   4. D. At the optic chiasm, where the nasal fibers cross
   Show answer to question 16

   Answer: A. In the occipital cortex, where the optic radiations end

   Fibers serving corresponding points in the two retinas travel apart in the optic tract and come progressively closer together as the pathway runs backward, so congruity increases with how posterior the lesion is: tract defects are typically incongruous, occipital defects strikingly congruous. Occipital lesions also classically spare the macula, attributed to the macula's very large cortical representation and dual blood supply. Chiasmal lesions give bitemporal rather than homonymous defects, and temporal-lobe lesions, which catch the radiations where they loop forward (Meyer's loop), lie well in front of the occipital cortex and give less congruous defects.

2. Question 17

   A field returns 6/13 fixation losses, yet the gaze-tracking graph is quiet and the technician observed steady fixation throughout. The most likely explanation is:

   1. A. The patient is malingering or is not making a genuine effort
   2. B. The gaze tracker malfunctioned and failed to record real eye movements
   3. C. The bowl background was set brighter than the standard 31.5 apostilbs
   4. D. The blind spot was mapped poorly, or the head shifted after mapping
   Show answer to question 17

   Answer: D. The blind spot was mapped poorly, or the head shifted after mapping

   The Heijl-Krakau method counts a fixation loss whenever the patient responds to a stimulus placed in the mapped blind spot, which assumes the mapping is accurate and the head has not moved since. A sloppy initial map, a head that slid on the chin rest, or an unusually small blind spot all manufacture fixation losses in a perfectly cooperative patient — and the quiet gaze tracker is the clue that the eye itself was steady. A tracker that missed real eye movements is ruled out as well, because the technician watched the eye and saw steady fixation. A wrong bowl background shifts thresholds across the field but does not put a seen stimulus inside the blind spot. The fix is mechanical: re-check chin and forehead position and alignment, remap the blind spot, and re-run.

Visual Fields study guide →

1. Question 18

   A patient has a fixed, non-reactive left pupil after prior iris trauma, and the physician wants to know whether the left optic nerve is also involved. The technician can still assess this by:

   1. A. Running the swinging-flashlight test, watching only the reactive right pupil
   2. B. Reporting that afferent testing is impossible while the left pupil cannot move
   3. C. Measuring the near response in the left eye with an accommodative target
   4. D. Measuring both pupils in bright and dim light and recording the anisocoria in millimeters
   Show answer to question 18

   Answer: A. Running the swinging-flashlight test, watching only the reactive right pupil

   Because each eye's afferent signal drives both pupils, one working pupil is all the test needs — this is the reverse RAPD method. Swing the light as usual and watch the reactive right pupil: if it dilates when the light moves onto the left eye, the afferent defect is in the left eye. Anisocoria measurements and near testing say nothing about the afferent limb, and declaring the test impossible would miss an optic neuropathy behind a damaged iris.

Pupillary Assessment study guide →

1. Question 19

   Reading in minus-cylinder form, the single (sphere) lines clear at −2.00 with the axis wheel at 070; the triple (cylinder) lines then clear at −3.50. The lens is:

   1. A. −5.50 −1.50 × 070
   2. B. −3.50 −1.50 × 160
   3. C. −2.00 −1.50 × 070
   4. D. −2.00 −1.50 × 160
   Show answer to question 19

   Answer: C. −2.00 −1.50 × 070

   The more-plus (less-minus) drum position gives the sphere, −2.00. The difference between the two drum readings gives the cylinder, −1.50. In minus-cylinder form the axis is the wheel setting at which the SPHERE lines cleared, so 070. Recording 160 names the other principal meridian and would be dispensed as a completely different lens; taking the more-minus reading (−3.50) as the sphere describes yet another lens; and the two drum readings are the meridional powers — they are never summed.

Lensometry study guide →

1. Question 20

   Keratometry reads 43.00 D @ 180 and 45.50 D @ 090. Expressed as a minus cylinder, the corneal astigmatism is:

   1. A. −2.50 D × 090, against-the-rule
   2. B. −2.50 D × 090, with-the-rule
   3. C. −2.50 D × 180, against-the-rule
   4. D. −2.50 D × 180, with-the-rule
   Show answer to question 20

   Answer: D. −2.50 D × 180, with-the-rule

   The meridians differ by 2.50 D. A minus cylinder carries its power 90° from its axis, so the minus power has to sit in the steep 090 meridian — which puts the axis at 180, along the flat meridian. A steep vertical meridian is with-the-rule, the pattern typical of younger eyes; corneas drift against-the-rule with age. Writing the axis at the steep meridian instead of the flat one is the classic reversal, and it is exactly the error that misaligns an astigmatic surgical plan.

Keratometry study guide →

1. Question 21

   An ophthalmic solution is labeled 2.5%. Taking a commercial drop as approximately 0.05 mL, how much drug does one drop deliver?

   1. A. 0.125 mg
   2. B. 0.25 mg
   3. C. 1.25 mg
   4. D. 12.5 mg
   Show answer to question 21

   Answer: C. 1.25 mg

   Percentage strength means grams of drug per 100 mL, so the anchor to memorize is that 1% equals 10 mg/mL. A 2.5% solution is therefore 25 mg/mL, and 25 mg/mL × 0.05 mL gives 1.25 mg in a single drop. The same arithmetic explains a familiar safety rule: phenylephrine 10% is 100 mg/mL, so one drop carries about 5 mg of a potent vasopressor — which is why the 2.5% strength is preferred in infants, the elderly, and anyone with cardiovascular disease.

Pharmacology study guide →

1. Question 22

   Three-step testing shows a right hypertropia in primary position that increases in left gaze and increases further on right head tilt. This pattern isolates:

   1. A. The right superior oblique
   2. B. The left superior rectus
   3. C. The right inferior oblique
   4. D. The left inferior rectus
   Show answer to question 22

   Answer: A. The right superior oblique

   Step one names the higher eye, implicating the right depressors or the left elevators. Step two, worse in left gaze, narrows the field to the right superior oblique or the left superior rectus. Step three separates them: tilting the head right demands intorsion of the right eye, and if the superior oblique cannot contribute its share of that torsion the unopposed right superior rectus elevates the eye, so the hyper grows. The technician measures every position and both tilts; naming the palsy remains the physician's call.

Ocular Motility study guide →

1. Question 23

   A glaucoma suspect had myopic LASIK years ago. Central corneal thickness now measures 480 μm and Goldmann applanation reads 15 mmHg. The technician charting this should recognize that:

   1. A. A thin cornea makes applanation over-read, so the true pressure is probably below 15 mmHg
   2. B. Corneal thickness affects the reading mainly above about 600 μm, so 480 μm needs no comment
   3. C. A thin, surgically flattened cornea resists the prism less, so applanation tends to under-read
   4. D. After LASIK, a standard correction table should be applied and the corrected value charted instead
   Show answer to question 23

   Answer: C. A thin, surgically flattened cornea resists the prism less, so applanation tends to under-read

   Goldmann is calibrated around a central thickness near 520 μm. Thinner corneas resist the prism less and read low, and laser ablation changes corneal biomechanics on top of simply removing tissue, so a post-refractive eye can read lower still. There is no single universally accepted correction nomogram, which is why charting a silently corrected number is worse than charting the raw one: it hides the measurement the physician wants to see. The technician's contribution is the measured pressure, the pachymetry value, and the surgical history in the same place.

Tonometry study guide →

1. Question 24

   At the start of a session the technician mounts the focusing rod in front of the slit lamp's objective and focuses the slit beam on its flat face. The purpose of this step is to:

   1. A. Calibrate the slit-width scale against a known standard before the session's slit-lamp photography
   2. B. Confirm that the illumination bulb is centered and properly seated in its housing
   3. C. Set the interpupillary distance by sliding the eyepiece tubes in or out until the two views fuse into one image
   4. D. Set each eyepiece separately, starting at maximum plus and turning down until the target first looks sharp
   Show answer to question 24

   Answer: D. Set each eyepiece separately, starting at maximum plus and turning down until the target first looks sharp

   The rod places a flat target exactly where the slit beam comes to focus, so it is the reference for making the viewing and illumination systems parfocal — that is, for making the microscope's focal plane coincide with the plane of the slit image for that observer's eyes. Each observer sets each eyepiece independently, beginning at full plus and reducing, because starting on the plus side keeps accommodation relaxed and stops the observer from focusing the instrument with their own ciliary muscle. Skip it and the joystick position that looks sharp is not the position where the beam is actually focused, which quietly degrades photography, reticle measurement and any subsequent applanation. Interpupillary distance is set separately by sliding the eyepiece tubes until a single image is seen; slit width and bulb centering are unrelated adjustments.

Equipment Maintenance and Repair study guide →

1. Question 25

   A soft toric ordered for −2.75 −1.25 × 090 is assessed at the slit lamp. On three separate observations the 6 o'clock scribe mark sits 10° to the examiner's left of vertical — the lens has rotated clockwise from the examiner's view. Applying the LARS rule, the axis that should be ordered is:

   1. A. 070
   2. B. 080
   3. C. 090
   4. D. 100
   Show answer to question 25

   Answer: D. 100

   LARS — Left Add, Right Subtract: rotation to the examiner's left is added to the prescribed axis, so 090 + 10 = 100. Ordering the compensated axis lets the lens settle onto the intended 090 in habitual wear. Two conditions must hold before compensating: the rotation has to be consistent across repeated checks, and the lens must otherwise fit well. A lens that rotates to a different position each time is unstable, and an unstable lens needs a different design rather than a recalculated axis.

Contact Lenses study guide →

1. Question 26

   Two days after a visit, a technician realizes a pachymetry value was charted in the wrong patient's electronic record. The correct handling is to:

   1. A. Correct the entry using the amendment function, leaving the original visible, then chart the value correctly and notify the physician
   2. B. Ask a colleague with administrator rights to overwrite the entry under its original date and time so the chart reads cleanly and no one notices the mistake
   3. C. Delete the erroneous entry so the record is no longer misleading, then enter the value in the correct chart
   4. D. Fix it quietly, since the error was caught before anyone acted on the value
   Show answer to question 26

   Answer: A. Correct the entry using the amendment function, leaving the original visible, then chart the value correctly and notify the physician

   A medical record is a legal document, and its integrity depends on the original entry remaining visible next to its correction. Electronic systems keep an audit trail of every view, entry, and edit, so a deletion or a back-dated overwrite is both discoverable and far more damaging than the original mistake — it reads as falsification rather than as a correction. Use the amendment or addendum function, signed and dated as of today with a brief reason for the change. The paper equivalent is a single line through the error with initials, date, and a brief reason, never obliteration or correction fluid. A wrong-chart entry also carries clinical risk in both directions: one patient's chart now holds a value that could drive a decision, and the other's is missing one, so the physician is told rather than the fix being made silently.

Medical Ethics, Legal and Regulatory Issues study guide →

1. Question 27

   Acute endophthalmitis after routine cataract surgery most often grows an organism that was already living on the patient before the operation. That organism is:

   1. A. Pseudomonas aeruginosa or another gram-negative rod carried in the healthy tear film
   2. B. Candida albicans or another yeast carried on the patient's skin and mucous membranes
   3. C. Streptococcus pneumoniae or another streptococcus carried in the patient's nose and throat
   4. D. Staphylococcus epidermidis or another coagulase-negative staphylococcus on the lid margin
   Show answer to question 27

   Answer: D. Staphylococcus epidermidis or another coagulase-negative staphylococcus on the lid margin

   The normal ocular surface is not sterile: coagulase-negative staphylococci dominate it, with diphtheroids (Corynebacterium) and smaller numbers of Staphylococcus aureus alongside them. When the globe is opened, that resident flora is the nearest available inoculum, and coagulase-negative staphylococci are accordingly the organisms most often recovered from acute post-cataract endophthalmitis. This is exactly why the preoperative preparation concentrates on the lids, lashes and conjunctival sac rather than on the air in the room, and why a technician never treats a lash or lid-margin touch during preparation as a trivial event. Streptococci, which colonize the nose and throat, and Candida, a mucosal commensal, can cause endophthalmitis but account for a far smaller share of post-cataract cases. Pseudomonas and other gram-negative rods are not part of the usual resident flora of a healthy eye and usually point to a contaminated source or trauma.

Microbiology study guide →

1. Question 28

   A new progressive wearer returns because the frame now rides low: the fitting cross sits about 3 mm below pupil center as worn, and the patient must lift the chin to reach the reading zone. The frame has adjustable nose pads. The adjustment that raises the frame is to:

   1. A. Increase the pantoscopic tilt at the temples
   2. B. Spread the nose pads farther apart
   3. C. Bring the nose pads closer together
   4. D. Lengthen the temples so the bend starts farther behind the ear
   Show answer to question 28

   Answer: C. Bring the nose pads closer together

   Narrowing the pad spread makes the pads rest higher on the narrowing part of the nasal bridge, which lifts the whole frame; spreading them apart lets the frame settle lower. Height matters more on a progressive than on any other lens, because the corridor and near zone are referenced to the fitting cross — a fitting cross that has dropped 3 mm pushes the reading zone out of comfortable downgaze and produces exactly this chin-up complaint. Verify the corrected height against the permanent engravings before concluding the lens design or the prescription is at fault; increasing pantoscopic tilt changes the angle of the front rather than raising it, and lengthening the temple so the bend sits behind the ear crest lets the frame slide down further rather than lifting it.

Spectacle Skills study guide →