Ophthalmology: AIIMS MAY 2012

Q-1. Corneal dystrophies are usually
a) Primarily unilateral
b) Primarily bilateral
c) Primarily unilateral without systemic disease
d) Primarily bilateral with systemic disease

Answer: Primarily bilateral
Explanation:
Corneal dystrophies:
Inherited disorder and restricted to the cornea
Non inflammatory
Not associated with systemic diseases
Bilateral and manifested occasionally at birth but more usually first or second decade

Q-2. Weakness of both adduction and abduction is seen in
a) Duane’s retraction syndrome type 1
b) Duane’s retraction syndrome type 2
c) Duane’s retraction syndrome Type 3
d) All

Answer: Duane’s retraction syndrome Type 3
Explanation:
Duane’s retraction syndrome is a rare, congenital disorder of eye movement.
Duane’s retraction syndrome type 1: Most common type
Abduction is limited, but adduction is normal or nearly so.
Duane’s retraction syndrome type 2:
Adduction of the affected eye is limited, whereas abduction of the eye is normal or only slightly limited.
Duane’s retraction syndrome type 3:
Adduction and abduction of the affected eye is limited.

Q-3. Area of fundus seen with direct ophthalmoscope is
a) 1 DD
b) 2 DD
c) 3 DD
d) 4 DD

Answer: 2 DD
Explanation:
Direct ophthalmoscope:
Most common practised method for routine fundus examination
Image is erect, virtual and 15 times magnified in emmetropes (More in myopes and less in hypermetropes)
Area of field: 2 Disc Dioptres

Q-4. Gyrate atrophy patient with defective ornithine amino-transferase will be benefited by
a) Ornithine free diet
b) Arginine free diet
c) Pyridoxine and Vit B12
d) Vitamin B1 B6 and B12

Answer: Arginine free diet
Explanation:
Gyrate atrophy, a recessive eye disease involving progressive vision loss due to chorio-retinal degeneration, is associated with the deficiency of the mitochondrial enzyme ornithine amino-transferase with consequent hyperornithinemia.
Ornithine is mainly produced from arginine.
Near total elimination of arginine with supplementation of essential amino acids has been found to be beneficial in gyrate dystrophy.

Q-5. In patients with anterior uveitis, decrease in vision due to posterior segment involvement can occur because of
a) Visual floaters
b) Inflammatory disc edema
c) Exudative retinal detachment
d) CME

Answer: CME
Explanation:
Cystoid macular edema:
Cystoid macular edema refers to collection of fluid in outer plexiform and inner nuclear layer of retina, central around the foveola.
It occurs in a variety of pathological conditions such as intraocular inflammation (uveitis, Behcet’s), central or branch retinal vein occlusion, diabetic retinopathy and most commonly following cataract extraction.
Clinical features:
Visual loss
Ophthalmoscopy: Honey comb appearance
Fundus flourscein angiography: Flower petal appearance

Q-6. On Fundoscopic examination of a patient, a red dot is seen. He has a history of being hit by a tennis ball. What is the probable cause?
a) Macular hole
b) Berlin’s edema
c) Macular tear
d) Macular bleed

Answer: Berlin’s edema
Explanation:
Berlin’s edema or Commotio retinae:
It is common occurrence following a blow on the eye.
It manifests as milky white cloudiness involving a considerable area of the posterior pole with a cherry red spot in the foveal region.
It may disappear after some days or may be followed by pigmentary changes.

Q-7. Ocular dendritic cells have
a) HLA 1
b) HLA 2
c) Both
d) None

Answer: HLA 2
Explanation:
The uveal tract contains rich networks of both resident macrophages and MHC class II dendritic cells.
MHC class II: B cells, Macrophage and dendritic cells

Q-8. A patient presented with unilateral proptosis which was compressible and increases on bending forward. No thrill or bruit was present. MRI shows a retro-orbital mass with enhancement. The likely diagnosis is
a) AV malformations
b) Orbital encephalocoecle
c) Orbital varix
d) Neurofibromatosis

Answer: Orbital varix
Explanation:
Orbital varices are a vascular hamartoma typified by a plexus of low pressure, low flow, thin walled and distensible vessels that intermingle with the normal orbital vessels.
If freely communicating with the orbital circulation, engorgement of varices can occur by increasing venous pressure through the Valsalva maneuver, bending posture, coughing or straining and these, in turn, lead to the clinical characteristics of variable proptosis, intermittent pain, and orbital hemorrhage.

Q-9. A 40 year old male with diabetes presents with vitreous hemorrhage. What is the cause?
a) Posterior retinal detachment
b) Neo-vascularization at disc
c) Central retinal vein occlusion
d) Trauma to central retinal artery

Answer: Neo-vascularization at disc
Explanation:
Proliferative diabetic retinopathy in diabetics:
It is more common in patients with juvenile onset diabetes.
The hallmark of proliferative diabetic retinopathy is the occurrence of neo-vascularization.
Diabetic vitreous hemorrhage secondary to proliferative diabetic retinopathy is a cause of severe vision loss in diabetic patients.

Q-10. A young adult presented with diminished vision. On examination he has anterior uveitis, vitritis, focal necrotizing granuloma and macular spot. What is the most probable diagnosis?
a) Proteus syndrome
b) White dot syndrome
c) White dot syndrome
d) Ocular toxoplasmosis

Answer: Ocular toxoplasmosis
Explanation:
Congenital toxoplasmosis:
Convulsion
Chorio-retinitis
Intra-cranial calcification
Important points:
In active stage, the typical lesion is necrotic granulomatous retino-choroiditis involving the macular region.
Typical chorio-retinal lesion of acquired toxoplasmosis is similar to congenital toxoplasmosis.