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Arab Board Ophthalmology Clinical & Oral study materials
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Arab Board Ophthalmology Clinical & Oral practice questions

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Question 1Anterior Segment and Cornea

A 24-year-old contact lens wearer presents with a central corneal epithelial defect, a feathery infiltrate with a ring-shaped distribution, and severe pain out of proportion to findings. What is the most appropriate initial management?

  1. Observation with lubricants and review in 48 hours
  2. Topical corticosteroid alone to reduce inflammation
  3. Topical fortified antibiotics with hourly dosing after corneal scraping Correct answer.
  4. Topical antiviral therapy with acyclovir ointment

Explanation

A ring infiltrate in a contact lens wearer suggests Pseudomonas or another bacterial keratitis, and standard care is corneal scraping for culture followed by intensive fortified topical antibiotics. Steroids and antivirals are not first-line here, and observation risks rapid corneal melting.

Question 2Anterior Segment and Cornea

Which corneal layer is primarily responsible for the majority of corneal tensile strength?

  1. Epithelium
  2. Bowman layer
  3. Stroma Correct answer.
  4. Endothelium

Explanation

The stroma, comprising about 90% of corneal thickness with organized type I collagen lamellae, provides most of the cornea's tensile strength. The epithelium and endothelium are cellular monolayers, and Bowman layer contributes little to structural integrity.

Question 3Anterior Segment and Cornea

A patient with keratoconus has a best-corrected visual acuity of 6/9 with a rigid gas-permeable lens but reports intolerable lens discomfort. Which surgical option is most appropriate next?

  1. Corneal collagen cross-linking
  2. Penetrating keratoplasty
  3. Photorefractive keratectomy
  4. Deep anterior lamellar keratoplasty Correct answer.

Explanation

Deep anterior lamellar keratoplasty replaces the diseased anterior stroma while preserving the host endothelium, which is preferable in keratoconus because the endothelium is healthy. It avoids the endothelial loss and rejection risk of penetrating keratoplasty.

Question 4Anterior Segment and Cornea

A 60-year-old presents with a painful vesicular rash on the forehead and a dendritic corneal lesion with terminal bulbs. What is the most appropriate treatment?

  1. Oral acyclovir with topical steroid only after epithelial healing Correct answer.
  2. Topical acyclovir plus topical corticosteroid
  3. Topical corticosteroid alone
  4. Topical antibiotic and patching

Explanation

Herpes zoster ophthalmicus with dendritic keratitis is treated with systemic antivirals; topical steroids are used for stromal inflammation only after the epithelium has healed. Steroids applied to an active epithelial infection can worsen it.

Question 5Anterior Segment and Cornea

Which finding best distinguishes a true dendritic ulcer of herpes simplex from a pseudodendrite?

  1. Positive staining with rose bengal only
  2. Association with a foreign body
  3. Location at the limbus
  4. Presence of terminal bulbs and fluorescein staining of the branches Correct answer.

Explanation

True herpetic dendrites have terminal bulbs and stain with fluorescein, reflecting epithelial destruction. Pseudodendrites are typically elevated, lack terminal bulbs, and stain poorly with fluorescein.

Question 6Anterior Segment and Cornea

A patient with chronic blepharitis develops a corneal ulcer with hypopyon and a Gram stain showing gram-positive cocci in clusters. Which organism is most likely?

  1. Staphylococcus aureus Correct answer.
  2. Pseudomonas aeruginosa
  3. Fusarium species
  4. Streptococcus pneumoniae

Explanation

Gram-positive cocci in clusters are characteristic of Staphylococcus species, a common cause of keratitis associated with chronic blepharitis. Pseudomonas is gram-negative, Streptococcus forms chains, and Fusarium is a filamentous fungus.

Question 7Anterior Segment and Cornea

Which of the following is the most common cause of infectious keratitis in developed countries?

  1. Bacterial infection Correct answer.
  2. Herpes simplex virus
  3. Acanthamoeba
  4. Fungal infection

Explanation

Bacterial keratitis is the most common cause of infectious keratitis in developed countries, frequently associated with contact lens wear. Viral and fungal keratitis occur but are less common overall.

Question 8Anterior Segment and Cornea

A patient with keratoconus shows progressive steepening on topography over 12 months. What is the most appropriate intervention to slow progression?

  1. Topical corticosteroid
  2. Corneal collagen cross-linking Correct answer.
  3. Rigid gas-permeable contact lenses
  4. Radial keratotomy

Explanation

Corneal collagen cross-linking uses riboflavin and ultraviolet A to stiffen the cornea and is the established treatment to halt keratoconus progression. Contact lenses improve vision but do not alter progression.

Question 9Anterior Segment and Cornea

Which corneal dystrophy is associated with a mutation in the TGFBI gene and shows granular deposits in the anterior stroma?

  1. Granular corneal dystrophy Correct answer.
  2. Lattice corneal dystrophy
  3. Macular corneal dystrophy
  4. Fuchs endothelial dystrophy

Explanation

Granular corneal dystrophy is caused by TGFBI mutations and produces discrete hyaline deposits in the anterior stroma. Lattice dystrophy also involves TGFBI but shows amyloid lines, and macular dystrophy involves CHST6.

Question 10Anterior Segment and Cornea

A 70-year-old presents with gradual bilateral vision loss, and slit-lamp examination shows central corneal guttae and stromal edema. What is the most likely diagnosis?

  1. Lattice corneal dystrophy
  2. Anterior basement membrane dystrophy
  3. Fuchs endothelial corneal dystrophy Correct answer.
  4. Pseudophakic bullous keratopathy

Explanation

Fuchs endothelial dystrophy is characterized by central corneal guttae and progressive endothelial decompensation leading to stromal edema. It is bilateral and typically affects older adults.

Question 11Anterior Segment and Cornea

Which of the following is the treatment of choice for a large, non-healing neurotrophic corneal ulcer?

  1. Tarsorrhaphy or amniotic membrane with aggressive lubrication Correct answer.
  2. Corneal transplant
  3. Topical corticosteroid
  4. Topical antibiotic alone

Explanation

Neurotrophic ulcers result from loss of corneal sensation and impaired healing, so protecting the ocular surface with tarsorrhaphy or amniotic membrane plus intensive lubrication is central to management. Steroids impair healing and transplantation is reserved for perforation.

Question 12Anterior Segment and Cornea

Which topical medication is most likely to cause a corneal epithelial toxicity with a whorl-like keratopathy?

  1. Timolol
  2. Latanoprost
  3. Amiodarone Correct answer.
  4. Chloroquine

Explanation

Amiodarone is associated with vortex or whorl-like corneal epithelial deposits. Timolol and latanoprost are not typically associated with whorl keratopathy, and chloroquine affects the retina.

Question 13Anterior Segment and Cornea

A patient with a history of recurrent corneal erosion syndrome has a loose epithelial sheet on the slit lamp after waking. What is the most appropriate initial management?

  1. Immediate penetrating keratoplasty
  2. Hypertonic saline ointment and lubricants with consideration of anterior stromal puncture Correct answer.
  3. Topical anesthetic drops for long-term use
  4. Topical corticosteroid

Explanation

Recurrent corneal erosion is managed initially with lubricants and hypertonic saline to reduce epithelial edema, with anterior stromal puncture or diamond burr for refractory cases. Long-term topical anesthetics are contraindicated.

Question 14Anterior Segment and Cornea

Which factor is most strongly associated with the development of a corneal graft rejection?

  1. Small graft size
  2. Use of topical antibiotics
  3. Prior corneal neovascularization Correct answer.
  4. Younger donor age

Explanation

Corneal neovascularization allows immune cells access to the graft and is a major risk factor for rejection. Larger grafts and prior grafts also increase risk, whereas small grafts reduce it.

Question 15Anterior Segment and Cornea

A patient with severe dry eye has punctate epithelial erosions and a tear film break-up time of 3 seconds. Which test best confirms aqueous deficiency?

  1. Pachymetry
  2. Schirmer test Correct answer.
  3. Corneal topography
  4. Tear osmolarity

Explanation

The Schirmer test measures tear production and helps identify aqueous-deficient dry eye when wetting is reduced. Tear osmolarity supports dry eye diagnosis but does not specifically quantify aqueous production.

Question 16Anterior Segment and Cornea

Which of the following is a recognized complication of laser-assisted in situ keratomileusis (LASIK)?

  1. Endothelial decompensation
  2. Flap dislocation Correct answer.
  3. Retinal detachment
  4. Lens subluxation

Explanation

Flap-related complications, including dislocation, striae, and epithelial ingrowth, are specific to LASIK because a hinged flap is created. Endothelial decompensation and retinal detachment are not typical LASIK complications.

Question 17Anterior Segment and Cornea

A patient with a corneal abrasion from a fingernail develops a hypopyon and a grey infiltrate 48 hours later. What is the most appropriate next step?

  1. Perform corneal scraping for culture and start fortified topical antibiotics Correct answer.
  2. Prescribe oral antihistamine
  3. Apply a pressure patch and discharge
  4. Prescribe topical steroid and review in a week

Explanation

A corneal infiltrate with hypopyon after trauma indicates microbial keratitis, and corneal scraping with intensive fortified antibiotics is standard. Steroids and patching would be inappropriate in this setting.

Question 18Anterior Segment and Cornea

Which structure is located at the anterior most portion of the corneal stroma and is absent in the central cornea of some individuals?

  1. Dua layer
  2. Bowman layer Correct answer.
  3. Endothelium
  4. Descemet membrane

Explanation

Bowman layer is an acellular condensation of collagen situated beneath the epithelium and is not regenerated after injury. Descemet membrane lies posteriorly and the Dua layer is a pre-Descemet stromal layer.

Question 19Anterior Segment and Cornea

Which condition is characterized by bilateral, symmetric, peripheral corneal thinning with an intact central cornea?

  1. Pellucid marginal degeneration
  2. Terrien marginal degeneration Correct answer.
  3. Marginal keratitis
  4. Mooren ulcer

Explanation

Terrien marginal degeneration causes bilateral, symmetric peripheral thinning with intact epithelium and lipid deposition, typically superiorly. Mooren ulcer is painful and progressive, and pellucid thinning is inferior.

Question 20Anterior Segment and Cornea

Which of the following is a contraindication to corneal collagen cross-linking?

  1. Progressive keratoconus
  2. Corneal thickness less than 400 microns Correct answer.
  3. Post-LASIK ectasia
  4. Pellucid marginal degeneration

Explanation

Corneal cross-linking requires sufficient stromal thickness to protect the endothelium from ultraviolet damage; a thickness below about 400 microns is a relative contraindication unless a hypotonic riboflavin protocol is used. Progressive ectasia is an indication, not a contraindication.

Question 21Anterior Segment and Cornea

A 35-year-old presents with a painful red eye and a dendritic ulcer after using a contact lens while swimming. Which organism should be suspected?

  1. Candida albicans
  2. Staphylococcus epidermidis
  3. Acanthamoeba Correct answer.
  4. Herpes simplex virus

Explanation

Acanthamoeba keratitis is strongly associated with contact lens exposure to water and can present with severe pain and epithelial defects that may mimic dendrites. Herpes simplex is not water-associated, and the other organisms are less linked to swimming.

Question 22Anterior Segment and Cornea

Which of the following is the most appropriate treatment for a perforated corneal ulcer less than 2 mm in size?

  1. Observation alone
  2. Topical corticosteroid
  3. Cyanoacrylate tissue adhesive with a bandage contact lens Correct answer.
  4. Radial keratotomy

Explanation

Small corneal perforations can be sealed with cyanoacrylate tissue adhesive and a bandage contact lens to restore integrity while healing occurs. Steroids impair healing and observation risks aqueous leak and infection.

Question 23Anterior Segment and Cornea

Which of the following describes the correct mechanism of action of riboflavin in corneal collagen cross-linking?

  1. It inhibits matrix metalloproteinases
  2. It directly cross-links collagen without light
  3. It promotes epithelial cell proliferation
  4. It acts as a photosensitizer that generates reactive oxygen species under ultraviolet A Correct answer.

Explanation

Riboflavin absorbs ultraviolet A light and generates reactive oxygen species that induce covalent cross-links between collagen fibrils. It requires ultraviolet A activation and is not a direct cross-linker.

Question 24Anterior Segment and Cornea

A patient with a known history of herpes simplex keratitis presents with a geographic ulcer after using topical steroids. What is the most appropriate management?

  1. Increase topical steroid
  2. Start topical antiviral and taper the steroid Correct answer.
  3. Apply a pressure patch
  4. Add topical antibiotic and continue steroid

Explanation

Steroid use can reactivate herpes simplex and cause a geographic ulcer, so an antiviral should be started and the steroid tapered. Continuing or increasing steroids would worsen the epithelial infection.

Question 25Anterior Segment and Cornea

Which corneal finding is characteristic of keratoconus on retinoscopy?

  1. Kayser-Fleischer ring
  2. Cherry red spot
  3. Scissoring of the red reflex Correct answer.
  4. Oil droplet sign

Explanation

Scissoring of the retinoscopic reflex occurs in keratoconus because of irregular astigmatism from corneal ectasia. The oil droplet sign is seen on ophthalmoscopy, and the other findings relate to retinal or metabolic disease.

Question 26Anterior Segment and Cornea

A 45-year-old contact lens wearer presents with a painful red eye. Slit-lamp examination shows a ring-shaped corneal infiltrate with an intact overlying epithelium and no anterior chamber reaction. Which organism is most characteristically associated with this presentation?

  1. Herpes simplex virus
  2. Pseudomonas aeruginosa
  3. Staphylococcus aureus
  4. Acanthamoeba species Correct answer.

Explanation

A ring-shaped stromal infiltrate with an intact epithelium in a contact lens wearer is characteristic of Acanthamoeba keratitis, which often produces a radial keratoneuritis and a ring abscess as the disease progresses. The intact epithelium and indolent course help distinguish it from typical bacterial keratitis.

Question 27Cataract and Refractive Surgery

Which formula is most appropriate for intraocular lens power calculation in an eye with an axial length of 30.5 mm?

  1. Barrett Universal II
  2. SRK/T Correct answer.
  3. Hoffer Q
  4. Haigis

Explanation

In very long eyes, theoretical formulas based on a fixed or optimized A-constant such as SRK/T are traditionally preferred because they avoid the tendency of some regression formulas to underpredict lens power. Modern formulae such as Barrett Universal II also perform well, but among the classic options listed SRK/T is the standard choice for high axial myopia.

Question 28Cataract and Refractive Surgery

A patient reports glare and haloes around lights at night two weeks after uncomplicated phacoemulsification with a multifocal intraocular lens. What is the most appropriate initial management?

  1. Topical pilocarpine
  2. Nd:YAG capsulotomy
  3. Immediate IOL exchange
  4. Reassurance and observation Correct answer.

Explanation

Dysphotopsia with multifocal IOLs is common in the early postoperative period and often diminishes as neuroadaptation occurs over weeks to months. Reassurance and observation are therefore the first step unless symptoms are severe or persistent.

Question 29Cataract and Refractive Surgery

During phacoemulsification, the surgeon notices the anterior chamber shallowing and the nucleus moving toward the cornea despite adequate irrigation. Which complication should be suspected first?

  1. Wound burn
  2. Iris prolapse
  3. Suprachoroidal hemorrhage
  4. Posterior capsule rupture Correct answer.

Explanation

A sudden loss of anterior chamber stability with forward movement of the nucleus during phacoemulsification suggests a posterior capsule rupture with fluid misdirection into the vitreous. Immediate recognition and modification of technique are required to prevent nucleus drop.

Question 30Cataract and Refractive Surgery

Which biometric parameter most strongly affects the accuracy of IOL power calculation in an eye with previous myopic laser refractive surgery?

  1. Central corneal thickness
  2. Effective corneal power Correct answer.
  3. Anterior chamber depth
  4. White-to-white diameter

Explanation

After corneal refractive surgery, standard keratometry overestimates corneal power because it assumes a fixed anterior-to-posterior curvature ratio that no longer applies. Accurate estimation of effective corneal power is the key determinant of IOL power accuracy in these eyes.

Question 31Cataract and Refractive Surgery

What is the most common cause of early postoperative corneal edema after uncomplicated phacoemulsification?

  1. Surgical endothelial trauma Correct answer.
  2. Infection
  3. Acute rise in intraocular pressure
  4. Endothelial toxicity from viscoelastic retention

Explanation

Transient corneal edema in the early postoperative period most often reflects endothelial cell loss from ultrasonic energy and instrument contact during surgery. It usually clears as remaining endothelial cells pump fluid out of the stroma.

Question 32Cataract and Refractive Surgery

A dense brown cataract in a patient with a shallow anterior chamber and pseudoexfoliation is planned for surgery. Which step most reduces the risk of intraoperative complications?

  1. Use of a single-plane clear corneal incision
  2. High vacuum and high aspiration settings from the outset
  3. Adequate pupil dilation and capsule stabilization with a device Correct answer.
  4. Immediate continuous curvilinear capsulorhexis under air

Explanation

Pseudoexfoliation weakens the zonules and is associated with poor dilation, so achieving adequate mydriasis and supporting the capsule reduces the risk of capsular tear and zonular dialysis. Careful, gentle hydrodissection and reduced settings also help.

Question 33Cataract and Refractive Surgery

Which finding on preoperative assessment most strongly suggests that a patient will be dissatisfied with a multifocal intraocular lens?

  1. Mild dry eye disease
  2. Astigmatism of 1.5 dioptres
  3. A history of well-controlled hypertension
  4. Significant corneal irregular astigmatism Correct answer.

Explanation

Irregular corneal astigmatism degrades the optical quality of the retinal image and amplifies the dysphotopsia associated with diffractive multifocal optics. Such patients generally do better with a monofocal or toric monofocal lens.

Question 34Cataract and Refractive Surgery

What is the recommended approach when the anterior capsule tear extends toward the posterior capsule during phacoemulsification?

  1. Immediately implant an anterior chamber IOL
  2. Continue phacoemulsification at full power
  3. Convert to extracapsular extraction or use low-flow settings and viscoelastic protection Correct answer.
  4. Perform a large capsulotomy with scissors

Explanation

An enlarging capsular tear requires reducing fluid turbulence and protecting the remaining capsule with viscoelastic while completing cortex removal gently. If the tear is uncontrolled, conversion to an extracapsular technique may be needed.

Question 35Cataract and Refractive Surgery

Which type of astigmatism is corrected by a toric intraocular lens placed at the steep corneal meridian?

  1. Regular corneal astigmatism Correct answer.
  2. Irregular astigmatism
  3. Lenticular astigmatism alone
  4. Mixed astigmatism with a spherical equivalent of zero

Explanation

Toric IOLs are designed to neutralize regular corneal astigmatism by aligning the cylinder axis with the steep meridian. Preoperative marking and intraoperative alignment are critical for efficacy.

Question 36Cataract and Refractive Surgery

Which measurement is used to determine the required haptic-to-haptic size for a phakic intraocular lens?

  1. Central corneal thickness
  2. Axial length
  3. Anterior chamber depth
  4. White-to-white distance Correct answer.

Explanation

White-to-white distance, together with sulcus measurements, guides selection of phakic IOL length so the haptics rest appropriately in the ciliary sulcus. Undersizing risks rotation and endothelial touch.

Question 37Cataract and Refractive Surgery

A patient develops a shallow anterior chamber with a flat iris plane and a wound leak on the first postoperative day after clear corneal phacoemulsification. What is the most appropriate immediate action?

  1. Re-suture or seal the wound and reform the anterior chamber Correct answer.
  2. Prescribe topical steroids and review in one week
  3. Perform Nd:YAG laser iridotomy
  4. Apply a bandage contact lens and observe

Explanation

A wound leak with a flat anterior chamber threatens endothelial integrity and predisposes to infection and hypotony. The wound should be sealed, by suture or other means, and the anterior chamber reformed with balanced salt solution or viscoelastic.

Question 38Cataract and Refractive Surgery

Which factor most increases the risk of endophthalmitis after cataract surgery?

  1. Intracameral antibiotic prophylaxis
  2. Use of topical anesthesia
  3. Wound leakage on the first postoperative day Correct answer.
  4. Small incision size

Explanation

A leaking incision allows ingress of ocular surface flora and is a recognized risk factor for postoperative endophthalmitis. Wound integrity and aseptic technique are central to prevention.

Question 39Cataract and Refractive Surgery

A patient with a history of radial keratotomy is scheduled for cataract surgery. Which consideration is most important?

  1. Axial length measurement is unreliable
  2. A multifocal IOL is preferred
  3. The corneal curvature is stable and standard formulas apply
  4. The cornea may weaken and the incisions can open with pressure changes Correct answer.

Explanation

Radial keratotomy incisions reduce corneal tensile strength, and the cornea may undergo progressive hyperopic shift or rupture with relatively minor trauma or pressure. Surgical planning should avoid placing incisions near existing ones and limit intraocular pressure fluctuations.

Question 40Cataract and Refractive Surgery

What is the main advantage of femtosecond laser-assisted cataract surgery over conventional phacoemulsification?

  1. It eliminates the need for viscoelastic
  2. It removes the need for ultrasound energy in all cases
  3. It provides reproducible capsulotomy size and shape Correct answer.
  4. It prevents posterior capsule opacification

Explanation

Femtosecond laser pretreatment creates a precise, reproducible anterior capsulotomy and can fragment the nucleus, which may reduce ultrasound energy. It does not remove the need for viscoelastic or eliminate ultrasound entirely.

Question 41Cataract and Refractive Surgery

A patient with a history of uveitis is being considered for cataract surgery. Which step most improves the surgical outcome?

  1. Routine omission of perioperative steroids
  2. Aggressive control of inflammation before surgery Correct answer.
  3. Use of a multifocal IOL
  4. Immediate surgery during active inflammation

Explanation

In uveitic eyes, surgery should be performed only when inflammation is well controlled, with perioperative and postoperative steroid cover, because active inflammation increases the risk of synechiae, hypotony, and cystoid macular edema.

Question 42Cataract and Refractive Surgery

Which finding on optical biometry suggests that the eye may have a silicone oil-filled vitreous cavity?

  1. A markedly shortened axial length
  2. A very high keratometry reading
  3. An unusually long axial length with a low signal-to-noise ratio Correct answer.
  4. A shallow anterior chamber depth

Explanation

Silicone oil has a different refractive index and sound velocity than vitreous, which distorts measurements. Optical biometry may show poor signal quality, and the eye often has a long axial length from prior pathology.

Question 43Cataract and Refractive Surgery

Which is a recognized risk of implanting an anterior chamber intraocular lens in an eye with insufficient capsular support?

  1. Corneal endothelial decompensation Correct answer.
  2. Cystoid macular edema from capsular contraction
  3. Posterior capsule opacification
  4. Zonular dialysis

Explanation

Anterior chamber IOLs sit close to the corneal endothelium, and haptic or optic contact, together with intermittent inflammation, can lead to progressive endothelial cell loss and decompensation.

Question 44Cataract and Refractive Surgery

What is the primary mechanism by which a multifocal intraocular lens provides near vision?

  1. Corneal multifocality
  2. Increased depth of field from a small pupil
  3. Accommodation of the ciliary muscle
  4. Diffractive or refractive splitting of light into multiple foci Correct answer.

Explanation

Multifocal IOLs use diffractive or refractive optics to divide incoming light into distance and near foci, providing simultaneous vision. The eye does not accommodate because the pseudophakic lens is fixed.

Question 45Cataract and Refractive Surgery

Which parameter is most important when planning a toric intraocular lens for a patient with 2.5 dioptres of corneal astigmatism?

  1. Axial length
  2. Pupil size
  3. Accurate keratometry and axis marking Correct answer.
  4. Anterior chamber depth

Explanation

Toric IOL efficacy depends on accurate measurement of the magnitude and axis of corneal astigmatism and precise intraoperative alignment. Errors in keratometry or marking lead to residual astigmatism.

Question 46Cataract and Refractive Surgery

A patient with cataract and a corneal scar that obscures the red reflex is scheduled for surgery. Which technique modification is most helpful?

  1. Use of a multifocal IOL
  2. Use of trypan blue to stain the anterior capsule Correct answer.
  3. Omission of viscoelastic
  4. Use of a larger incision

Explanation

When the red reflex is poor, trypan blue staining of the anterior capsule improves visualization for performing a continuous curvilinear capsulorhexis. This reduces the risk of an irregular or radial tear.

Question 47Cataract and Refractive Surgery

Which of the following best describes the principle of the effective lens position in IOL power calculation?

  1. The diameter of the capsulorhexis
  2. The thickness of the crystalline lens
  3. The predicted postoperative position of the IOL along the optical axis Correct answer.
  4. The distance from the corneal apex to the fovea

Explanation

Effective lens position is the estimated postoperative location of the IOL along the optical axis, and errors in this estimate are a major source of refractive surprise. Formulae use axial length and keratometry, among other parameters, to predict it.

Question 48Cataract and Refractive Surgery

What is the most appropriate management for a patient with visually significant posterior capsule opacification six months after cataract surgery?

  1. Observation
  2. Nd:YAG laser posterior capsulotomy Correct answer.
  3. Topical steroid drops
  4. IOL exchange

Explanation

Posterior capsule opacification that reduces vision is treated with Nd:YAG laser capsulotomy, which creates a central opening in the opacified capsule. The procedure is generally safe and effective.

Question 49Glaucoma

Which optic disc finding is the earliest structural sign of glaucomatous damage on clinical examination?

  1. Total cupping of the disc with complete loss of the rim
  2. Pallor of the central disc cup
  3. Peripapillary atrophy
  4. Focal narrowing or loss of the neuroretinal rim at the superior or inferior pole Correct answer.

Explanation

Glaucomatous rim loss typically begins as focal thinning, most often at the superior and inferior poles where nerve fiber bundles are densest. This focal notching precedes generalized cupping and is detectable before visual field loss.

Question 50Glaucoma

A 62-year-old has intraocular pressure of 26 mmHg in both eyes, open angles on gonioscopy, and a normal-appearing optic disc with no field defect. Which diagnosis is most appropriate?

  1. Primary open-angle glaucoma
  2. Primary angle-closure suspect
  3. Normal-tension glaucoma
  4. Ocular hypertension Correct answer.

Explanation

Ocular hypertension requires elevated intraocular pressure with open angles and no evidence of glaucomatous optic neuropathy or field loss. Once structural or functional damage appears, the diagnosis becomes glaucoma.