Your FREE COT Flashcards 2026 – 250+ Cards

Outer fibrous (cornea + sclera), middle vascular uvea (iris, ciliary body, choroid), inner neural (retina).

Epithelium, Bowman's layer, stroma, Descemet's membrane, endothelium.

The endothelium — a non-regenerating single cell layer that maintains corneal deturgescence (dehydration).

The cornea provides ~⅔ of the eye's total power (~43 D of ~60 D); the crystalline lens supplies the rest.

Lipid (outer, from meibomian glands), aqueous (middle, lacrimal gland), and mucin (inner, goblet cells).

Ciliary body → posterior chamber → through the pupil → anterior chamber → trabecular meshwork → Schlemm's canal → episcleral veins.

By the ciliary body (ciliary processes / epithelium) in the posterior chamber.

The macula is the central retina responsible for sharp central vision; the fovea is its center, packed with cones, giving the best acuity.

Rods: night/peripheral, motion, no color, very light-sensitive. Cones: central, color (red/green/blue), high detail, need bright light.

Where retinal ganglion axons exit as the optic nerve — it has no photoreceptors, creating the physiologic blind spot ~15° temporal to fixation.

Puncta → canaliculi → lacrimal sac → nasolacrimal duct → inferior meatus of the nose.

The iris is the colored diaphragm; the pupil is its central aperture that controls light entering the eye (constricts in light, dilates in dark).

Sphincter pupillae (parasympathetic) constricts (miosis); dilator pupillae (sympathetic) dilates (mydriasis).

Emmetropia = light focuses exactly on the retina (no refractive error). Ametropia = a refractive error (myopia, hyperopia, astigmatism).

The eye is too long or too powerful, so light focuses in front of the retina; distance is blurry. Corrected with a minus (concave) lens.

The eye is too short or too weak, so light focuses behind the retina; near is blurry first. Corrected with a plus (convex) lens.

The cornea/lens has unequal curvatures (toric), so light focuses at two points instead of one. Corrected with a cylindrical lens.

Age-related loss of accommodation (the lens stiffens), making near focus difficult, typically after ~40. Corrected with a reading add.

The eye's ability to increase its focusing power for near objects — the ciliary muscle contracts, zonules relax, and the lens becomes more convex.

Normal is <120/80 mmHg; stage 1 hypertension is 130–139/80–89, stage 2 is ≥140/90 (current ACC/AHA categories).

Heart rate ~60–100 beats/min; respiratory rate ~12–20 breaths/min.

Pale, sweaty, lightheaded, slow pulse. Stop the procedure, recline the patient, elevate the legs, monitor, and call for help.

Hives, swelling, wheeze, hypotension after an allergen. First-line is intramuscular epinephrine; activate emergency response.

Right, left, up-right, up-left, down-right, down-left — each isolates a pair of yoke (agonist) muscles.

Diabetic retinopathy — microaneurysms, hemorrhages, exudates, and neovascularization; a leading cause of blindness. Control of glucose/BP is key.

CN III (oculomotor — most muscles), CN IV (trochlear — superior oblique), CN VI (abducens — lateral rectus). Mnemonic: LR6 SO4, rest 3.

The transition zone where the clear cornea meets the white sclera; it contains corneal stem cells and is a surgical landmark.

The clear mucous membrane covering the white of the eye (bulbar) and the inner eyelids (palpebral); it produces mucin and tears.

COA (entry/assistant) → COT (intermediate/technician) → COMT (advanced/technologist).

The clear gel that fills the large posterior cavity behind the lens, helping the eye keep its shape and transmit light to the retina.

The vascular middle layer between the retina and sclera; it supplies blood and nutrients to the outer retina.

Anterior chamber (between cornea and iris) and posterior chamber (between iris and lens); both are filled with aqueous humor.

Superior, inferior, medial, and lateral rectus, plus the superior and inferior oblique — six muscles per eye.

The lateral rectus abducts (turns the eye outward), controlled by CN VI (abducens).

They secrete the oily (lipid) outer layer of the tear film, which slows evaporation; their dysfunction is a common cause of dry eye.

About 97–99°F (≈36.1–37.2°C); ~98.6°F (37°C) is the classic average.

Retinal vessel changes from high blood pressure — narrowing, arteriovenous nicking, hemorrhages, and in severe cases optic-disc swelling.

A compressive lesion such as a posterior communicating artery aneurysm — a 'pupil-involving' CN III palsy is a neurologic emergency.

Symptoms are what the patient reports (subjective); signs are what the examiner observes or measures (objective).

It produces the watery (aqueous) middle layer of the tear film, which makes up most of the tear volume.

The patient's main reason for the visit, recorded in their own words — the foundation of the ophthalmic history.

Onset, Location, Duration, Character, Aggravating, Relieving, Timing, Severity — a structured way to document the chief complaint.

History of Present Illness — the detailed chronological account of the chief complaint and its associated symptoms.

Glasses/contact lens use, prior eye surgery or injury, glaucoma, amblyopia, eye drops, family eye history (glaucoma, macular degeneration).

Many drugs affect the eye — steroids (cataract/glaucoma), tamsulosin (floppy iris), hydroxychloroquine (retinal toxicity), amiodarone (corneal deposits).

OD = right eye (oculus dexter), OS = left eye (oculus sinister), OU = both eyes (oculus uterque).

The drug name and the specific reaction (e.g., hives vs. anaphylaxis vs. nausea); distinguish a true allergy from a side effect.

No Known Drug Allergies — documented when a patient reports no medication allergies.

Subjective = what the patient reports (symptoms, history). Objective = measurable findings (acuity, IOP, exam). Both belong in the chart.

Perform delegated testing and assist; do NOT diagnose, prescribe, or interpret results for the patient — that is the physician's role.

Review of Systems — a checklist of body systems screened for relevant symptoms beyond the chief complaint.

Photophobia = light sensitivity; diplopia = double vision; metamorphopsia = distorted/wavy vision (often macular).

Draw a single line through it, write 'error,' add the correct entry, then date and initial — never erase, scribble out, or use white-out.

It focuses the history and exam; everything documented connects back to why the patient came in, in their own words.

Document the discrepancy and verify with the patient/pharmacy; flag it for the physician — never silently overwrite.

Lifestyle and occupation affect eye disease and safety — smoking raises AMD risk; occupation guides safety-eyewear and visual-demand counseling.

A relevant symptom the patient specifically denies (e.g., 'no flashes or floaters') — documenting it shows the question was asked.

Glaucoma, macular degeneration, retinal detachment, and strabismus/amblyopia — all have a hereditary component.

Documenting the physician's exam findings and orders in real time in the medical record, at the physician's direction.

At 20 feet the patient reads what a normal eye reads at 40 feet — worse than normal. The bottom number is the test distance for a normal eye.

Logarithm of the Minimum Angle of Resolution — a uniform-step acuity scale (each line = 0.1 log unit, 5 letters) used in research (e.g., ETDRS charts).

It blocks unfocused peripheral rays, so improvement with a pinhole indicates uncorrected refractive error; no improvement suggests a media or retinal cause.

20 feet (6 m). If a patient misses letters, record e.g. 20/30 -2 (read the 20/30 line missing two letters).

Counting Fingers (CF), Hand Motion (HM), Light Perception (LP), then No Light Perception (NLP), with the test distance.

To measure the power of an existing spectacle lens — sphere, cylinder, axis, add, and prism — by neutralizing it.

Read the distance power, then move to the segment and read the near power; the add = near power minus distance power (always plus).

An objective refraction technique: a streak of light is swept across the pupil and the reflex movement is neutralized with lenses to find the refractive error.

'With' motion (reflex moves same direction) needs plus lenses; 'against' motion needs minus lenses; neutralization = no movement.

The single sphere that best represents a sphero-cylindrical lens: spherical equivalent = sphere + ½ × cylinder.

Refining the cylinder axis and power during subjective refraction by flipping the cross cylinder and asking 'which is clearer, one or two?'

1) New sphere = sphere + cylinder; 2) change the cylinder sign; 3) rotate the axis 90°.

+3.00 −1.00 × 180. (Sphere 2+1=3; flip cyl sign; axis 90+90=180.)

The distance from the back of the lens to the cornea (~12–14 mm). Adjust for high powers (>±4.00 D) because effective lens power changes with distance.

A subjective check of refractive endpoint: a slightly under-minused eye sees red letters clearer; over-minused sees green clearer. 'Make red and green equal.'

The distance between the pupil centers; it aligns the optical centers of the lenses with the visual axes so the patient isn't induced into prism.

A unit of prism deviation: 1Δ displaces an image 1 cm at 1 meter. The base direction (BU, BD, BI, BO) names where the prism's base points.

Induced prism (Δ) = lens power (D) × decentration (cm). It quantifies prism created when looking away from a lens's optical center.

The front surface curvature of a lens; it affects fit, magnification, and how the lens looks, and is matched when remaking a lens.

A convex (converging) lens magnifies and corrects hyperopia/presbyopia. Moving it shows 'against' motion; objects appear larger.

A concave (diverging) lens minifies and corrects myopia. Moving it shows 'with' motion; objects appear smaller.

Photochromic: darken in UV. Polycarbonate: impact-resistant (safety/children). High-index: thinner lenses for strong prescriptions.

Base curve (mm), diameter (mm), and power (D); soft lenses also consider water content and material; the fit is checked for centration and movement.

A progressive corneal thinning/cone causing irregular astigmatism; rigid gas-permeable (RGP) or scleral lenses give the best vision.

It pools under the lens to show the tear film pattern — apical clearance vs. touch — so the fitter can judge the fit relationship.

Lenses mold the cornea (corneal warpage); readings are inaccurate until the cornea recovers (often hours to days for RGP).

Microbial keratitis (corneal infection/ulcer), especially Pseudomonas and Acanthamoeba — a sight-threatening emergency.

Distance acuity is tested at 20 feet (Snellen); near acuity is tested at ~14–16 inches with a reading card (e.g., Jaeger or reduced Snellen).

Measures the ability to distinguish an object from its background at varying contrast levels — can reveal deficits when acuity is still 20/20.

Measure visual acuity (and IOP and pupils) BEFORE dilating, because dilating drops blur near vision and change the pupil exam.

To detect a difference between the eyes (a weaker eye can hide behind a stronger one); occlude one eye completely without pressing on it.

To hold and quickly change trial lenses in front of the eye during refraction and refinement.

A significant difference in refractive error between the two eyes; large amounts in childhood can cause amblyopia.

A bifocal has a visible line dividing distance and near; a progressive (PAL) blends distance to near with no visible line.

Working distance (m) ≈ 1 / add power, so a +2.50 add focuses at about 1 / 2.50 = 0.40 m (≈16 inches).

To correct vertical prism imbalance at near in anisometropic patients reading through bifocals.

A thin, lightweight press-on prism (a series of small prism segments) applied to a lens, often as a temporary correction for diplopia.

Base-up (BU), base-down (BD), base-in (BI, toward the nose), base-out (BO, toward the ear) — name where the prism's thick base points.

It causes irregular astigmatism that spectacles correct poorly; rigid or scleral contact lenses give better vision by masking the irregular surface.

Correcting astigmatism in a soft lens; it has a stabilization design (e.g., prism ballast) to keep the cylinder axis oriented.

The base curve is chosen relative to the flattest keratometry (K) reading so the lens aligns properly with the cornea.

A gross bedside screening: the examiner compares the patient's peripheral field to their own, presenting fingers in each quadrant, one eye at a time.

Automated = static threshold perimetry (computer presents stationary lights of varying brightness). Goldmann = kinetic (a moving target maps isopters).

An area of reduced or absent vision within the visual field (e.g., the physiologic blind spot, or a pathologic defect in glaucoma).

Nasal step, arcuate (Bjerrum) scotoma, and paracentral defects, reflecting nerve-fiber-layer loss; central vision is spared until late.

The optic chiasm (e.g., pituitary tumor) — crossing nasal fibers are affected, so both temporal fields are lost.

Posterior to the chiasm (optic tract, radiations, or occipital cortex) on the side opposite the field loss.

Fixation losses, false positives, and false negatives; high rates make the field unreliable and may need a repeat.

Shining light in one eye constricts that same eye's pupil. The consensual reflex constricts the fellow (unstimulated) eye.

A relative afferent pupillary defect — the swinging-flashlight test shows the affected pupil dilate when light swings to it; it signals optic nerve/retinal disease.

Unequal pupil sizes. Note whether the difference is greater in light (parasympathetic/CN III problem) or dark (sympathetic/Horner's).

Pupils Equal, Round, Reactive to Light and Accommodation; also note size in mm in light and dark, and shape.

A test for tropias (manifest deviation): cover one eye and watch the OTHER for a shift to take up fixation, revealing a strabismus.

Rapidly switching the cover between eyes to dissociate them and reveal the total deviation (tropia + phoria); measured with prisms.

Eso = inward turn, exo = outward turn, hyper = upward turn (of the deviating eye). A '-phoria' is the latent (controlled) version.

Ocular alignment by where a penlight reflects on each cornea; each mm of decentration ≈ 7° (≈15Δ) of deviation.

Reduced vision in an eye that developed poorly in childhood (from strabismus, anisometropia, or deprivation) despite a healthy eye — best treated early.

Depth perception from binocular vision; tested with the Titmus (fly) or Randot stereo tests, scored in seconds of arc.

The closest point both eyes can converge on a target before one breaks outward; a receded NPC suggests convergence insufficiency.

Involuntary rhythmic eye oscillation (jerk or pendular); it can be congenital or acquired (neurologic, vestibular, drug-related).

Constriction of the fellow (non-stimulated) pupil when light is shone in one eye — both pupils respond together.

A sympathetic-pathway lesion; the affected pupil is small (miosis) with mild ptosis, and the anisocoria is greater in the dark.

A white pupillary reflex (instead of red); in children it can signal retinoblastoma or cataract and must be evaluated urgently.

A test of binocular fusion and suppression using red/green glasses and four lights; the number and color of dots seen reveals fusion, suppression, or diplopia.

It dissociates the eyes to measure phorias; one eye sees a line, the other a dot, and prisms quantify the deviation.

An estimate of strabismus angle by placing prism over the deviating eye until the corneal light reflexes are symmetric.

An esotropia worse at distance with limited abduction of the affected eye (the lateral rectus is weak).

Ductions are movements of one eye; versions are conjugate movements of both eyes together (tested in the cardinal positions).

A central scotoma affects fixation/reading (macular or optic-nerve disease); a peripheral scotoma affects the side field (e.g., glaucoma, retinal disease).

Progressive constriction toward central/tunnel vision, with the central island and a temporal crescent often last to go.

A loss of one quadrant of the visual field, usually from a lesion in the optic radiations (temporal or parietal lobe).

It confirms correct fixation and the eye's orientation; an enlarged or shifted blind spot can also indicate disc pathology.

Intraocular pressure (IOP) — the fluid pressure inside the eye, a key screening value for glaucoma.

About 10–21 mmHg; pressures consistently above 21 raise concern for glaucoma, though glaucoma can occur at normal pressures.

Goldmann applanation tonometry — it flattens a fixed corneal area; the force needed equals the pressure (Imbert-Fick principle).

A topical anesthetic (e.g., proparacaine) and fluorescein dye, so the examiner can see the mires (semicircles) to align.

Thick corneas read falsely high; thin corneas read falsely low. Pachymetry helps interpret the IOP.

Non-contact 'air-puff' tonometer (no anesthetic needed) and the Tono-Pen / iCare rebound tonometer (handheld).

Wipe and disinfect per protocol (e.g., diluted bleach or hydrogen peroxide soak, then rinse/dry) or use disposable tips/covers to prevent infection transmission.

The curvature (in mm or diopters) of the central cornea along its two principal meridians — the 'K readings' — and corneal astigmatism.

Contact-lens base-curve fitting, IOL power calculation for cataract surgery, and detecting/monitoring corneal astigmatism and keratoconus.

Focus the eyepiece, then align and superimpose the plus and minus mires along each meridian; the lack of doubling gives the reading.

A color map of the entire corneal surface curvature (not just the center), used to detect irregular astigmatism, keratoconus, and to plan refractive surgery.

Measuring ocular dimensions — chiefly axial length and keratometry — to calculate the intraocular lens (IOL) power for cataract surgery.

Optical biometry is non-contact and very precise (preferred). Ultrasound A-scan touches the eye (or uses immersion) and is used when media are too dense for optics.

Applanation touches the cornea and can compress (shortening axial length, error). Immersion uses a saline standoff for more accurate, non-compressing readings.

Axial length — a 1 mm error produces roughly 2.5–3 diopters of postoperative refractive error.

Measurement of corneal thickness (CCT), important for glaucoma IOP interpretation, refractive surgery screening, and corneal disease.

Confirm no active corneal infection/abrasion, instill anesthetic, use clean/disposable tips, and avoid pressure on the globe.

For a thin sphere, pressure = force ÷ area; flattening a fixed corneal area means the force applied equals the intraocular pressure.

The mires appear too thick and the reading is falsely high; too little makes thin mires and a falsely low reading.

IOP fluctuates over the day (often highest in the morning); a single reading may miss peaks, so timing is noted and sometimes repeated.

Pressing on the globe or a tight collar/breath-holding, and excess fluorescein or a wide mire; thick corneas also read high.

Corneal curvature in millimeters of radius and/or in diopters of power, for each of the two principal meridians.

Significant corneal astigmatism — the difference between the steep and flat meridians is the corneal cylinder.

To eliminate the examiner's own accommodation, which would otherwise introduce error into the readings.

It feeds modern IOL power formulas and helps assess angle-closure risk (a shallow chamber suggests a narrow angle).

Axial length and keratometry (corneal power); errors in either translate directly into postoperative refractive surprise.

Usually emmetropia or slight myopia for distance, chosen with the patient; the IOL power is selected to hit that target.

Whether the cornea is thick enough to safely remove tissue; a too-thin cornea is a contraindication to LASIK.

Measuring acuity under a glare source, which uncovers functional vision loss from cataract or corneal haze missed in dim conditions.

A non-invasive cross-sectional scan of the retina and optic nerve using light interferometry — it measures retinal/RNFL thickness for glaucoma and macular disease.

The retinal nerve fiber layer (RNFL) thickness and the ganglion cell complex; thinning indicates glaucomatous damage.

Photographing the retina, optic disc, macula, and vessels to document and monitor disease (diabetic retinopathy, glaucoma, AMD).

IV sodium fluorescein is injected and timed retinal photos show blood flow, leakage, and ischemia — used in diabetic retinopathy and AMD.

Rare anaphylaxis (have emergency drugs ready). Expected: transient nausea and yellow-orange discoloration of skin and urine.

The choroidal circulation (deeper than the retina), useful in occult choroidal neovascularization and choroidal disorders.

A 2-D ultrasound image of the posterior eye/orbit when the view is blocked (dense cataract, vitreous hemorrhage) — to detect retinal detachment, tumors, foreign bodies.

Imaging and counting the corneal endothelial cells (cell density, morphology) — important before cataract surgery and in corneal disease.

Estimating the best possible vision behind a cataract (projects an acuity chart through clearer media) to predict post-surgery acuity.

Red-green color deficiency (congenital), and acquired defects from optic nerve disease; pseudoisochromatic plates hide a number from the color-deficient.

Detecting and monitoring central (macular) field distortion (metamorphopsia) or scotomas, as in macular degeneration; patients self-monitor at home.

Measuring the forward protrusion of the globe (proptosis), used in thyroid eye disease and orbital masses.

A measure of aqueous tear production: a paper strip in the lower fornix wets a length in 5 minutes; <5–10 mm suggests dry eye.

The seconds from a blink to the first dry spot in the fluorescein-stained tear film; <10 seconds indicates tear-film instability (dry eye).

Sharp focus, correct exposure, proper field/centration of the pathology, and accurate labeling of eye (OD/OS) and date.

A dye-free OCT technique that images retinal and choroidal blood flow by detecting moving red cells across repeated scans.

Standardized A-scan characterizes tissue/lesions (echography); diagnostic A-scan/biometry measures axial length for IOL calculation.

Motion artifact — broken or doubled vessels and a distorted segmentation line; re-acquire the scan.

Lids, conjunctiva, cornea, and anterior chamber findings — useful for tracking lesions, ptosis, and pre/post-operative appearance.

Consent covers the IV dye risks (rare anaphylaxis); precise timing of the photo sequence is essential to interpret the dye transit.

The choroidal circulation — ICG fluoresces in the infrared and stays in vessels, showing deeper choroidal flow.

It maps lipofuscin in the retinal pigment epithelium without dye, useful in macular degeneration and dystrophies.

Steady central or eccentric fixation aligns the desired field (e.g., disc-centered vs. macula-centered) for a clear, reproducible image.

Scanning-laser instruments that quantify the optic nerve head and nerve-fiber layer to detect and monitor glaucoma.

They contact patient skin between every patient; cleaning prevents transmission of infection (a noncritical-item precaution).

A sympathomimetic (adrenergic) mydriatic such as phenylephrine — it dilates without affecting accommodation (no cycloplegia).

An anticholinergic that paralyzes accommodation (and dilates) — e.g., tropicamide (short), cyclopentolate, atropine (longest). Used for cycloplegic refraction.

Any dilating drop in a patient with narrow/occludable angles can precipitate angle-closure glaucoma — screen and counsel for red eye/pain after dilation.

Constricts the pupil (and lowers IOP by opening the angle), e.g., pilocarpine — historically for glaucoma and angle-closure.

Proparacaine and tetracaine — used before tonometry, foreign-body removal, and biometry. Never dispense for home use (delays healing).

They lower IOP by reducing aqueous production. Caution in asthma/COPD, bradycardia, and heart block (systemic absorption).

Increase uveoscleral outflow (first-line, once daily). Side effects: iris/lash darkening, lengthened lashes, periocular pigmentation, conjunctival hyperemia.

They decrease aqueous humor production (e.g., topical dorzolamide/brinzolamide, oral acetazolamide).

Pressing the inner corner after instilling drops blocks nasolacrimal drainage, increasing ocular absorption and reducing systemic side effects.

About 5 minutes, so the second drop doesn't wash out the first.

A suspension (e.g., some steroids) must be shaken before use so the drug is evenly dispersed; a solution does not.

Bacterial: purulent discharge, often Staph/Strep/Haemophilus. Viral (often adenovirus): watery discharge, very contagious, preauricular node.

Pseudomonas aeruginosa (rapid bacterial ulcer) and Acanthamoeba (linked to water/poor hygiene) — both can cause vision loss.

Treat all blood and body fluids as potentially infectious: hand hygiene, gloves/PPE as needed, safe sharps handling, and equipment disinfection between patients.

Hand hygiene before and after every patient contact (and between exams), plus disinfecting shared instruments and chin/forehead rests.

Critical (enters sterile tissue) = sterilize; semicritical (touches mucosa, e.g., tonometer tip) = high-level disinfection; noncritical (intact skin) = low-level.

Steam sterilization under pressure — commonly 121°C at 15 psi for ~15–30 min (or 132°C flash cycles); kills all microorganisms including spores.

Chemical indicators (tape/strips that change color) confirm exposure; biological indicators (spore tests) confirm actual sterilization, run periodically.

Semicritical items that touch mucous membranes but aren't easily sterilized (e.g., applanation tips) — using agents like glutaraldehyde or hydrogen peroxide per protocol.

Cleaning optics, replacing bulbs, disinfecting chin/forehead rests between patients, and checking alignment and illumination.

Drift causes inaccurate readings; the Goldmann tonometer is checked with a calibration bar/weight at set positions, and other devices per manufacturer schedule.

Atropine lasts up to ~1–2 weeks; tropicamide is short-acting (a few hours), making tropicamide the routine dilating drop.

They dilate by different mechanisms (phenylephrine stimulates the dilator; tropicamide relaxes the sphincter), giving a wider, more reliable dilation.

Pilocarpine (a cholinergic miotic) can reverse pupil dilation; clinically, dilation is simply allowed to wear off.

Patients with hypertension or cardiovascular disease, because systemic absorption can raise blood pressure; the 2.5% strength is safer.

Topical fluorescein stains corneal/conjunctival epithelial defects (abrasions, ulcers) green under cobalt-blue light.

A preservative (e.g., benzalkonium chloride) and not touching the tip to any surface; discard if contaminated or past the date.

The instrument must stay in the disinfectant for the full manufacturer-specified time/temperature to kill pathogens — shortcuts fail.

Sterile = free of ALL microorganisms including spores; disinfected = most pathogens killed but not necessarily spores.

Wrapped items stay sterile in storage; flash/immediate-use sterilization is for an item needed right away and is used straight from the autoclave.

Dispose directly into a puncture-resistant, leak-proof, labeled sharps container without recapping by hand.

Hand hygiene is universal; gloves and additional PPE are added when contacting body fluids or for infectious cases.

Drift produces inaccurate axial-length or curvature readings, which propagate into wrong IOL powers and contact-lens fits.

A clouding of the eye's natural crystalline lens, causing blurred vision and glare; treated by surgical removal and IOL implantation.

The standard cataract surgery: an ultrasonic probe emulsifies and aspirates the cloudy lens through a small incision, then an IOL is implanted.

Prepare/sterilize instruments, position and drape the patient, hand instruments, maintain the sterile field, and document — never exceeding delegated tasks.

Only sterile items touch sterile items; keep within view and above waist level; consider edges/borders non-sterile; never reach over the field or turn your back on it.

The physician explains the procedure, risks, benefits, and alternatives; the technician may witness/document the signature but does not obtain the consent itself.

A team pause to verify correct patient, correct procedure, and correct site/eye (and IOL) — a Universal Protocol safety step to prevent wrong-site surgery.

Laser refractive surgery that reshapes the corneal stroma under a flap to correct refractive error (myopia, hyperopia, astigmatism).

A laser procedure that opens a cloudy posterior capsule ('secondary cataract') that can form months to years after cataract surgery, restoring vision.

A monofocal IOL focuses at one distance (usually far). A multifocal/EDOF IOL provides multiple focal points to reduce glasses dependence.

Thoroughly clean and rinse to remove detergent/debris (Toxic Anterior Segment Syndrome is caused by retained residues), then sterilize properly.

A progressive optic neuropathy (cupping + visual field loss), often associated with elevated IOP, that causes irreversible vision loss if untreated.

Open-angle: chronic, painless, gradual field loss (most common). Angle-closure: can be acute — pain, red eye, halos, nausea, fixed mid-dilated pupil — an emergency.

Central retinal (macular) degeneration causing loss of central vision; dry (drusen, atrophy) and wet (neovascular, treated with anti-VEGF injections) forms.

The retina separates from the underlying tissue — an emergency. Warning signs: sudden flashes, a shower of floaters, and a curtain/shadow over the field.

Reinforce the physician's instructions (drops, follow-up, postoperative care), confirm understanding, and answer general questions within scope — not diagnosing.

Wash hands, tilt head back, pull down the lower lid to form a pocket, instill one drop without touching the eye/tip, close gently, and use punctal occlusion.

Federal law protecting patient health information (PHI); share PHI only on a need-to-know basis, secure records/screens, and never discuss patients publicly.

Defer to the physician — interpreting findings or giving a diagnosis is outside the technician's scope of practice.

Failing to act as a reasonably prudent technician would; following protocols, documenting accurately, and staying within scope reduces liability.

Immediate copious irrigation with saline/water for at least 15–30 minutes (before other steps), then check pH and seek physician care urgently.

A scratch of the corneal epithelium causing pain, tearing, and photophobia; fluorescein staining shows the defect under cobalt-blue light.

Treat as urgent — possible retinal artery occlusion, retinal detachment, or stroke. Notify the physician immediately; do not delay.

Chin in the rest, forehead against the band, eyes aligned to the canthus marker, comfortable and stable — adjust table/chair height first.

Patient name/ID, date, and which eye (OD/OS) — correct labeling prevents serious errors in interpretation and treatment.

Consider table edges, anything below the waist, and the back of a gown non-sterile; only the front from chest to waist and gloved hands are sterile.

Refractive lasers (LASIK/PRK) reshape the cornea to change focus; non-refractive lasers treat disease (e.g., YAG capsulotomy, retinal photocoagulation).

Laser treatment of the peripheral retina to reduce abnormal new-vessel growth in proliferative diabetic retinopathy.

Wet macular degeneration, diabetic macular edema, and retinal vein occlusion — anti-VEGF drugs injected into the vitreous.

Wavelength-specific protective eyewear, warning signage on the door, restricted access, and a labeled laser-safe zone.

Sudden severe eye pain and headache with a red eye, halos around lights, nausea/vomiting, and a fixed mid-dilated pupil — an emergency.

Treat as a possible retinal detachment — an urgent finding; notify the physician immediately for same-day evaluation.

Do not rub; protect the eye, ask about high-velocity exposure (grinding), and have the physician evaluate — an intraocular foreign body is sight-threatening.

Accurately measure and record blood pressure, pulse, and sometimes oxygen saturation, and report abnormal values to the physician.

Respect the refusal, document it, explain the purpose, and notify the physician — never coerce the patient.

The nature of the procedure, its risks and benefits, alternatives, and the chance to ask questions — explained by the physician.

To document services correctly for the record and billing; inaccurate coding is a compliance and legal risk.

Provide the measured data the physician has authorized, but defer interpretation and diagnosis to the physician (scope of practice).