Q-1. Which of the following topical agents causes hetero-chromia iridis?
a) Latanoprost
b) Prednisolone
c) Timolol
d) Olopatadine
Answer: Latanoprost
Explanation:
Heterochromia iridis occurs in several conditions:
Waardenburg syndrome
Fuchs hetero-chromic iridocyclitis
Melanosis oculi
Iris melanoma
Horner syndrome
Certain drugs, such as Latanoprost
Q-2. Evisceration of eye is not done in
a) Malignancy
b) Pan-ophthalmitis
c) Trauma
d) Hemorrhage
Answer: Malignancy
Explanation:
Indications of evisceration:
Pan-ophthalmitis
Expulsive choroidal hemorrhage
Bleeding anterior staphyloma
Severe traumatic injury
Q-3. Vitreous humor has high concentration of what compared to blood
a) Glucose
b) Sodium
c) Potassium
d) Ascorbate
Answer: Ascorbate
Explanation:
Ascorbic acid (AA) accumulates in vitreous at a concentration several times higher than in plasma.
It has been suggested that AA may serve as an antioxidant that protects ocular tissues from free radical attack.
Important points:
Composition of aqueous is similar to plasma except that it has high concentration of ascorbate, pyruvate and lactate; and low concentration of protein, urea and glucose.
Q-4. Corneal sensation is lost in which nerve palsy
a) Naso-Cilliary nerve
b) Supra-trochlear nerve
c) Infra-trochlear nerve
d) Infra-orbital nerve
Answer: Naso-Cilliary nerve
Explanation:
Loss of sensation in naso-ciliary nerves which are branch of ophthalmic division of 5th cranial nerve is of great importance.
Loss of sensation in cornea abolishes corneal reflex leaving the cornea unprotected and can lead to ulcer formation on cornea.
Q-5. High molecular weight proteins in cataractous lens seen only in humans
a) HM 1 and 2
b) HM 2 and 4
c) HM 3 and 4
d) HM 2 and 3
Answer: HM 3 and 4
Explanation:
The high molecular weight fractions isolated from nuclear cataracts:
Fraction HM3 and HM4 are only found in cataractous lens.
Q-6. Universal marker of limbal stem cells
a) Elastin
b) Keratin
c) Collagen
d) ABCG2
Answer: ABCG2
Explanation:
At the corneo-scleral junction in an area known as the limbus, there is a population of limbal epithelial stem cells.
Limbal epithelial stem cells share common features with other adult somatic stem cells including small size and high nuclear to cytoplasmic ratio.
They also lack expression of differentiation markers such as cyto-keratins 3 and 12.
ABCG2 has been proposed as a universal and conserved marker for stem cells from a wide variety of tissues.
Q-7. Multifocal ERG impulse records from
a) Rods
b) Ganglion cell layer
c) RPE layer
d) Macular cones
Answer: Macular cones
Explanation:
In patient with macular degeneration, the multifocal ERG technique is a useful tool to detect and quantify central cone function, especially in disease stages with no or subtle visible retinal changes.
Depending on the underlying disorder, patient with macular degeneration may show reduced and/or delayed central responses.
Q-8. True Statements regarding Direct Ophthalmoscopy are A/E:
a) 2 disc diameter field of vision
b) Image is virtual and erect
c) Magnification is 5 times
d) Self illuminated device
Answer: Magnification is 5 times
Explanation:
Direct Ophthalmoscopy is self illuminated device and most commonly plasticized method for routine fundus examination.
Characteristics of image formed in Direct Ophthalmoscopy:
Erect
Virtual
15 times magnification in emmetropes
Q-9. Granular dystrophy of cornea diagnosed by which stain?
a) Masson Trichrome
b) Congo red
c) PAS
d) Colloid iron
Answer: Masson Trichrome
Explanation:
Granular corneal dystrophy is an autosomal-dominant, bilateral, non-inflammatory condition that results in milky granular hyaline deposits in anterior stroma with clear-areas between these deposits.
When corneal specimens are obtained, light microscopy reveals eosinophilic hyaline deposits in the corneal stroma. Masson Trichrome stains the deposits bright red.
Q-10. A person comes with history of painful loss of vision with delayed recovery of vision after exposure to bright light. Most likely diagnosis is-
a) Retro-bulbar Neuritis
b) Aortic arch syndrome
c) Ocular Ischemic Syndrome
d) All
Answer: Retro-bulbar Neuritis
Explanation:
Sudden painful loss of vision:
Acute-angle closure glaucoma
Fracture of the lesser wing of the sphenoid bone
Optic neuritis
Temporal arteritis
Uveitis
Clinical presentations of retro-bulbar Neuritis:
Painful, sudden, progressive and profound visual loss
Lowered dark adaption
Visual obscuration in bright light
Impairment of color vision
Important point:
The most common reason for painless sudden visual loss is ischemia.
Q-11. Steroids are contra-indicated in
a) Herpes keratitis
b) Atopic dermatitis
c) Fungal corneal ulcer
d) Exposure keratitis
Answer: Herpes keratitis
Explanation:
Herpetic keratitis:
Epithelial keratitis:
Topical steroid are contraindicated in epithelial keratitis.
Stromal keratitis:
It is due to delayed type of hypersensitivity reaction to HSV.
Topical steroids are used for treatment.
Q-12. Right trochlear nerve palsy, all are present except
a) Right hypertropia
b) Diplopia on upper gaze and adduction
c) Right ex-torsion
d) Right head tilt
Answer: Right head tilt
Explanation:
Unilateral trochlear nerve (CN IV) palsy:
Hyper-deviation
Hypertropia on side of trochlear nerve palsy
Excyclo-torsion: Compensated by head tilt to opposite shoulder
Limited depression in adduction
Diplopia- vertical and worse on looking down