Free Ophthalmology mock test

Ophthalmology sample questions with answers

10 more original exam-style Ophthalmology questions, worked in full. They are not real or recalled exam questions, and none of them is in the mock above or on the bank page, so sit the mock first if you have not.

1. Question 1 · Glaucoma

   A 29-year-old man with -9.00 D myopia is referred because OCT reports 'borderline/outside normal limits' with red inferotemporal retinal nerve fibre layer sectors in both eyes. Intraocular pressure is 14 mmHg, discs are tilted with temporal crescents but have healthy rims, and repeated reliable 24-2 fields are normal. What is the most likely explanation?

   1. AA false-positive result ('red disease') because tilted, myopic discs with a temporally displaced nerve fibre bundle are poorly represented in the normative database
   2. BEarly pre-perimetric glaucoma requiring immediate initiation of a prostaglandin analogue
   3. CSegmentation failure caused by cystoid macular oedema
   4. DA physiological floor effect of the retinal nerve fibre layer
   Show answer and explanation

   Correct answer: A. A false-positive result ('red disease') because tilted, myopic discs with a temporally displaced nerve fibre bundle are poorly represented in the normative database

   High myopia shifts the temporal raphe and the peak nerve fibre bundles, and axial-length-related magnification is not corrected in most normative databases, so healthy myopic eyes are frequently flagged abnormal - the classic 'red disease' artefact. Treating on the strength of a colour-coded printout in the presence of healthy rims, normal pressure and normal fields is not justified; there is no macular oedema described; and the floor effect is a phenomenon of advanced, not early or absent, damage.

   Reference: AAO Basic and Clinical Science Course, Section 10: Glaucoma (2023-2024); European Glaucoma Society Guidelines, 5th edition (2020)

2. Question 2 · Cataract and Lens Surgery

   A patient with pseudoexfoliation has phacodonesis and about four clock hours of zonular dehiscence noted after capsulorhexis. Which device most reliably provides both intraoperative bag stability and long-term fixation in this situation?

   1. AAn anterior chamber intraocular lens
   2. BTwo iris retractors on the capsulorhexis edge left in place at the end of surgery
   3. CA standard closed-loop capsular tension ring alone
   4. DA Cionni modified capsular tension ring or Ahmed capsular tension segment sutured to the sclera
   Show answer and explanation

   Correct answer: D. A Cionni modified capsular tension ring or Ahmed capsular tension segment sutured to the sclera

   A standard capsular tension ring redistributes zonular forces and helps intraoperatively but cannot anchor the bag when a segment of zonule is absent, so progressive decentration and late in-the-bag dislocation remain likely. A Cionni ring or an Ahmed capsular tension segment has an eyelet that can be sutured to the sclera, providing definitive fixation of the deficient quadrant. An anterior chamber IOL sacrifices the capsular bag unnecessarily, and iris retractors are a temporary intraoperative aid only.

   Reference: AAO Basic and Clinical Science Course, Section 11: Lens and Cataract (2023-2024)

3. Question 3 · Paediatric Ophthalmology and Strabismus

   A 7-year-old has an esotropia of 30 prism dioptres in primary position, 45 prism dioptres in down gaze and 10 prism dioptres in up gaze, with elevation of each adducting eye on versions. What is the most appropriate surgical plan?

   1. ABilateral medial rectus recession alone
   2. BBilateral superior oblique tenotomy with medial rectus recession
   3. CBilateral medial rectus recession combined with bilateral inferior oblique weakening
   4. DBilateral lateral rectus resection with inferior rectus recession
   Show answer and explanation

   Correct answer: C. Bilateral medial rectus recession combined with bilateral inferior oblique weakening

   The deviation is larger in down gaze than up gaze, which defines a V-pattern esotropia, and the elevation of the adducting eye indicates inferior oblique overaction as its cause; therefore horizontal surgery should be combined with bilateral inferior oblique weakening. Horizontal recession alone leaves the pattern uncorrected, superior oblique weakening is used for A-patterns with superior oblique overaction, and lateral rectus resection would increase the esotropia.

   Reference: AAO Basic and Clinical Science Course, Section 6: Pediatric Ophthalmology and Strabismus (2023-2024)

4. Question 4 · Oculoplastics, Orbit and Lacrimal System

   A surgeon plans to reconstruct a full-thickness eyelid defect using a free tarsoconjunctival graft harvested from the contralateral upper eyelid for the posterior lamella. According to accepted reconstructive principles, what must the anterior lamella be reconstructed with?

   1. AA free full-thickness retroauricular skin graft
   2. BA vascularised skin-muscle advancement or transposition flap
   3. CA second free tarsal graft placed superficially
   4. DAmniotic membrane secured to the graft margins
   Show answer and explanation

   Correct answer: B. A vascularised skin-muscle advancement or transposition flap

   A fundamental principle of eyelid reconstruction is that at least one lamella must be a vascularised flap; placing a free graft against a free graft deprives both of a blood supply and leads to necrosis and contracture. Therefore a free posterior lamellar tarsoconjunctival graft must be covered by a vascularised myocutaneous advancement or transposition flap. A free skin graft or a second free graft violates this rule, and amniotic membrane is not a substitute for a vascularised anterior lamella in a full-thickness defect.

   Reference: AAO Basic and Clinical Science Course, Section 7: Oculofacial Plastic and Orbital Surgery (2023-2024)

5. Question 5 · Ocular Trauma and Ophthalmic Emergencies

   After adequate irrigation for an ammonia injury, a patient has a total corneal epithelial defect, stromal haze that obscures iris detail, and perilimbal blanching involving 5 clock hours. What is the Roper-Hall grade and the implied prognosis?

   1. AGrade II - good prognosis
   2. BGrade III - guarded prognosis
   3. CGrade IV - poor prognosis
   4. DGrade I - excellent prognosis
   Show answer and explanation

   Correct answer: B. Grade III - guarded prognosis

   Roper-Hall grade III is defined by total epithelial loss with stromal haze obscuring iris details and limbal ischaemia of one-third to one-half of the limbus, which corresponds to 5 of 12 clock hours; the prognosis is guarded. Grade II has a hazy cornea through which iris details are still visible with less than one-third limbal ischaemia and a good prognosis, while grade IV has an opaque cornea with more than one-half limbal ischaemia and a poor prognosis. The Dua classification refines this by grading limbal involvement in clock hours together with the percentage of conjunctival involvement, which is more discriminating in severe injuries.

   Reference: Roper-Hall MJ, Thermal and chemical burns, Trans Ophthalmol Soc UK (1965); Dua HS et al., Br J Ophthalmol (2001); AAO BCSC Section 8 (2023-2024)

6. Question 6 · Patient Safety, Professionalism, Ethics and Practice in the GCC

   A 50-year-old man has had a dense vitreous haemorrhage in the left eye; the right eye is 6/6 with a full field. He asks whether he may drive his private car. Which factor is most decisive in the assessment?

   1. AThe absolute acuity in the affected eye
   2. BWhether the better eye meets the acuity standard and the binocular horizontal visual field is adequate, together with a period of adaptation to the monocular state
   3. CThe presence of stereopsis, which is mandatory for all private driving licences
   4. DThe patient's subjective confidence when driving
   Show answer and explanation

   Correct answer: B. Whether the better eye meets the acuity standard and the binocular horizontal visual field is adequate, together with a period of adaptation to the monocular state

   Private (group 1) driving standards are based on the acuity achieved with both eyes open, an adequate binocular horizontal field, and, for newly monocular drivers, a period of adaptation before resuming driving. Acuity in the poorer eye alone is not determinative, stereopsis is not a licensing requirement for private driving, and subjective confidence is not an acceptable substitute for objective standards.

   Reference: DVLA Assessing Fitness to Drive - a Guide for Medical Professionals, visual disorders section (2024); Royal College of Ophthalmologists guidance on vision and driving

7. Question 7 · Glaucoma

   A 63-year-old hypermetropic woman has narrow angles. On static gonioscopy no angle structures are visible for 360 degrees. With gentle indentation using a four-mirror lens, the superior and temporal angles open to reveal the scleral spur, but nasally the iris remains adherent to the trabecular meshwork in a broad, irregular band that does not separate. What is the correct interpretation?

   1. AAppositional closure in all quadrants, so laser peripheral iridotomy alone will fully reopen the angle
   2. BPeripheral anterior synechiae nasally with appositional closure superiorly and temporally
   3. CPlateau iris syndrome, which is confirmed by the failure of the nasal angle to open
   4. DAn artefact of excessive indentation pressure with no pathological significance
   Show answer and explanation

   Correct answer: B. Peripheral anterior synechiae nasally with appositional closure superiorly and temporally

   Indentation gonioscopy displaces aqueous peripherally and separates iris that is merely in apposition; an area that fails to open represents permanent peripheral anterior synechiae. The angle therefore shows synechial closure nasally and reversible appositional closure elsewhere, which is why iridotomy alone cannot restore the full outflow area. Plateau iris is diagnosed by a persistently anteriorly positioned ciliary body with a double-hump sign after a patent iridotomy, not by focal non-opening; over-indentation causes corneal striae and falsely widened, not falsely closed, angles.

   Reference: European Glaucoma Society Terminology and Guidelines for Glaucoma, 5th edition (2020); Shields Textbook of Glaucoma, 7th edition (2020)

8. Question 8 · Cataract and Lens Surgery

   Midway through phacoemulsification in an 84-year-old hypertensive patient the anterior chamber shallows abruptly, the eye becomes firm, the red reflex is lost and the iris prolapses through the main incision. What is the immediate priority?

   1. APerform an immediate posterior sclerotomy to drain the choroidal haemorrhage
   2. BInject intracameral acetylcholine and continue with reduced bottle height
   3. CEnlarge the incision to deliver the nucleus quickly
   4. DClose the incisions immediately and securely to restore a closed globe and raise intraocular pressure
   Show answer and explanation

   Correct answer: D. Close the incisions immediately and securely to restore a closed globe and raise intraocular pressure

   This is a suprachoroidal (expulsive) haemorrhage, and the single most important step is rapid watertight closure of all incisions so that rising intraocular pressure tamponades the bleeding and prevents expulsion of intraocular contents. Enlarging the incision or continuing to operate accelerates expulsion. Immediate posterior sclerotomy during active bleeding is not the first move; drainage, if required, is generally delayed several days until the clot lyses.

   Reference: Yanoff & Duker, Ophthalmology, 6th edition (2023)

9. Question 9 · Paediatric Ophthalmology and Strabismus

   A 3-year-old with dense anisometropic amblyopia is tested with Teller acuity cards, which give a result close to age norms, yet the parents report the child ignores objects on that side and the fixation pattern is clearly non-central and non-maintained. What is the best explanation for the discrepancy?

   1. APreferential-looking grating acuity systematically overestimates acuity in amblyopia compared with recognition optotypes
   2. BTeller cards are invalid in the presence of anisometropia of any degree
   3. CGrating acuity is unaffected by refractive blur, so the result reflects true macular function
   4. DPreferential-looking testing measures contrast sensitivity rather than acuity
   Show answer and explanation

   Correct answer: A. Preferential-looking grating acuity systematically overestimates acuity in amblyopia compared with recognition optotypes

   Grating (resolution) acuity measured by preferential looking is well recognised to overestimate acuity in amblyopic eyes, sometimes by several lines, because amblyopia degrades recognition and crowded optotype acuity more than simple grating resolution. Teller cards remain valid in anisometropia, grating acuity is degraded by blur, and preferential looking measures resolution, not contrast sensitivity; therefore optotype testing should be used as soon as the child can cooperate.

   Reference: AAO Basic and Clinical Science Course, Section 6: Pediatric Ophthalmology and Strabismus (2023-2024)

10. Question 10 · Oculoplastics, Orbit and Lacrimal System

    Ten years after enucleation with a small primary implant, a patient has a deep superior sulcus, an apparently sunken prosthesis, upper lid pseudoptosis and backward tilt of the prosthesis, with lower eyelid laxity causing the prosthesis to slip. The socket lining and fornices are healthy with no contracture. What is the most appropriate management?

    1. AFit a larger and heavier prosthesis alone
    2. BLevator aponeurosis advancement for the ptosis
    3. CSecondary orbital implant or dermis-fat graft to restore orbital volume, combined with lower eyelid tightening
    4. DOrbital exenteration and fitting of a facial prosthesis
    Show answer and explanation

    Correct answer: C. Secondary orbital implant or dermis-fat graft to restore orbital volume, combined with lower eyelid tightening

    This is post-enucleation socket syndrome, caused by a deficit of orbital volume that produces enophthalmos of the prosthesis, a deep superior sulcus, pseudoptosis and backward tilt, aggravated by lower lid laxity; correction requires restoring volume with a secondary implant or dermis-fat graft together with horizontal lid tightening. Enlarging the prosthesis increases weight, stretches the lower lid further and worsens the cycle. Levator surgery treats the pseudoptosis symptomatically without addressing the volume deficit, and exenteration is destructive and has no role in a healthy socket.

    Reference: AAO Basic and Clinical Science Course, Section 7: Oculofacial Plastic and Orbital Surgery (2023-2024)