Sanjay' S MCQs for part-II

1.Trochlear nerve
A.Only cranial nerve to emerge from the dorsal aspect of brain.
B.Crossed cranial nerve innervating opposite superior oblique muscle
C.Long and slender nerve
D.Nucleus located at the level of inferior colliculus ventral to aqueduct sylvius.
E.Decussates completely in anterior medullary vellum.

A - E: True

2.Fourth nerve cranial palsies
A. Identical features are seen irrespective of whether nuclear, fascicular or peripheral.
B. Diplopia is avoided by the patient by adopting contralateral head tilt and turn with chin depression.
C. Congenital lesions may not be symptomatic until adult life.
D. Trauma causes bilateral ptosis.
E. Aneurysm is one of the common causes.
A - D: True E: False, vascular is common, aneurysms and tumour are rare.

3.Third cranial nerve palsies
A.Isolated 3rd N palsies are frequently basilar. ( occurs when the N passes through sub arachnoid space)
B.Trauma and aneurysms are most important causes of isolated palsies
C.Painless, pupillary sparing isolated palsies are due to aneurysms at junction of posterior communicating and internal carotid artery.
D.Intracavernous lesions are associated with 4th, 6th and 5th nerve lesions.
E. Lesions of inferior division of 3rd nerve in its intra orbital part may occur due to vascular or traumatic cause.
A - B: True C: False, painful and papillary involvement.
D - E: True; characterized by defective adduction, depression and dilation of pupil (parasympathetic fibres pass through N to inferior oblique.

4. Isolated 3rd cranial nerve palsies
A. 25% have no causes
B. Diabetes and hypertension are most common causes of pupil sparing palsies
C. Trivial trauma not associated with loss of consciousness should possibly indicate a basal intracranial tumour stretching the nerve trunk.
D. MRA, a non invasive technique can identify aneurysms 4mm and greater located at junction of posterior communicating and internal carotid artery.
E. Surgical treatment is to be considered six months after the onset of palsy.
A - E: True

5. CT scan orbit
A. Bone excavation with round or smooth outline in presence of calcification is common in pleomorphic adenoma.
B. Contiguous bone erosion with invasion with calcification in 1/3rd cases is seen in lacrimal gland carcinoma.
C. Fusiform enlargement of optic nerve is seen in optic nerve glioma
D. Tubular thickening and calcification of optic nerve is seen in optic nerve sheath meningioma
E. Poorly defined mass of heterogeneous density is seen in rhabdomyosarcoma
A: False; calcification is rare and indicates carcinoma
B - D: True
E: False; homogeneous density.

6. Third cranial nerve
A.Lesions involving medial rectus subnucleus causes WEBINO.
B. Lesions involving the entire 3rd nerve nucleus cause ipsilateral 3rd nerve palsy
sparing ipsilateral elevation but causing contralateral weakness of elevation.
C. Levator subnucleus lesions give rise to bilateral ptosis.
D. Benedikt syndrome occurs when the fascicle passes through red nucleus.
E. Weber’s syndrome occurs when the fascicle passes through cerebral peduncle.
A - E: True
WEBINO: wall eyed bilateral inter nuclear ophthalmoplegia is characterized by exotropia, defective convergence and adduction.

7. Convergence retraction nystagmus
A. Jerk nystagmus occurs on attempted down gaze.
B. Fast phase brings two eyes into convergence
C. Associated with protrusion of globe into orbit
D. Pinealoma and vascular accidents in pretectal area can cause it.
E. May be associated with lid retraction ( Collier’s sign) and light near disscociation.
A - False; upgaze B: True; C: False; retraction of globe D - E: True

8. Ocular nystagmus
A. Is due to sensory deprivation caused by defective vision.
B. Is vertical and jerky
C. Increased by convergence
D. Abnormal head posture may be associated to dampen nystagmus.
E. Associated with loss of central vision in early life(< 2years) due to cataract, macular hypoplasia.
A: True; B: False, horizontal and pendular; C: False dampened; D- E: True

9. Regarding orbital varices
A. Most cases are unilateral and located in upper nasal quadrant.
B. Phleboliths are seen in 20% cases on X ray/ CT.
C. Presentation is early childhood to late middle age with proptosis and visible lesions
D. Natural course is progressive enlargement associated with recurrent episodes of haemorrhage and thrombosis.
E. Surgery is technically difficult and reserved for cases with recurrent episodes of thrombosis, pain, proptosis and optic nerve compression.
A - E: True
10. Direct carotid cavernous fistula (CCF)
A. Abnormal communication between artery and vein in which vein becomes arterialized.
B. May occur after head injury or spontaneous rupture
C. Anterior segment ischaemia is common and occurs in 20% cases.
D. 6th nerve is affected in 50% with variable involvement of 3rd and 4th.
E. Intravascular balloons introduced via catheter into internal carotid artery is used for closure.
A - E: True

11. Indirect CCF
A. Communications are between meningeal branches of ICA/ECA and cavernous sinus.
B. Spontaneous rupture may be precipitated by minor trauma/straining in hypertensive patients
C. Red eye and 4th nerve palsy is common.
D. Low intra ocular pressure with dilated episcleral blood vessels.
E. Exaggerated ocular pulsation is seen in tonometry.
A, B: True; C- False, 6th nerve palsy; D- False, high IOP; E- True.

12. Regarding tonometers
A. Accuracy of non contact is only in low and middle range.
B. Pulsair tonometer is a non contact tonometer and provides clinically useful measurements comparable to Goldmann.
C. Tonopen overestimates a low IOP and underestimates a high IOP.
D. Tonopen is useful in distorted and oedematous cornea and also through bandage contact lens.
E. Perkins is a hand held tonometer useful in bed bound patients.
A - E: True

13. Torsion can be measured by
A. Synaptophore
B. Maddox wing
C. Adapted Lees screen
D. Awaya cyclo test
E. Bagolini glasses
A - E: True; also used are Maddox double rods

14. Ultrasound examination of eye
A. Helps in diagnosis and determining the tumour size.
B. In choroidal melanoma, is characterized by anterior border of tumour, acoustic hollowness, choroidal excavation and orbital shadowing.
C. In retinoblastoma detects presence of calcification.
D. Useful in detection of intra ocular foreign body, globe rupture, suprachoroidal haemorrhage in cases of trauma to the globe.
E. T sign in posterior scleritis is due to thickening of posterior sclera and fluid in sub tenon’s space.
A - E: True

15. Frequency doubling perimetry
A. Portable table top instrument
B. Requires dim illumination with patching
C. Stimuli are presented in 17/19 sectors in central 20*/ 30* depending on the program used.
D. Low spatial frequency sinusoidal gratings undergoes high temporal frequency counter phase flicker.
E. Reliability indices, probabilities, mean deviation and PSD are present in the print out.
A: True; B- False, normal lighting, viewing canopy automatically covers the eye not being tested so no need for occlusion. C - E: True

16. Dark adaptation
A. Retina and pupil react to decreased illumination and is useful in patients with nyctalopia.
B. Performed using Goldmann-Weekes adaptometer.
C. Sensitive curve is tripartite.
D. Alpha point occurs 20 min after dark adaptation.
E. Flash focused on foveola, only a cone plateau is recorded.
A - B: True
C: False; Curve is bipartite. The subject is pre-adapted to a standard amount of illumination and presented with series of flashes of light 11* below fixation. The intensity of flashes are controlled by neutral density filter and threshold plotted against time. The curve is obtained wherein initial rapid segment is cone followed by slower rod segment function.
D: False; Alpha point is inflection of curve where rod limit begins, rod-cone break”. Healthy eyes have it in 7-10 minutes of dark adaptation.
E: True; May be more sensitive than electroretinogram in certain disorders.

17. Electrophysiology in retinitis pigmentosa
A. Amplitude of scotopic and later photopic b wave is reduced in early stages with minimal fundus changes.
B. Delay in implicit time.
C. Electrooculogram shows absence of light rise.
D. Patients with loss of cone mediated response have poorer visual acuity and visual field scotoma encroaching closer to fixation compared to typical rod- cone type.
E. determination of any rod mediated response in electroretinogram is critical for diagnosis in any young patient suspected of retinitis pigmentosa.
A - E: True

18. MRI scans
A. Could be axial, saggital or coronal.
B. T1 weighted image of vitreous is dark
C. T1 weighted images are preferred for studying pathological changes
D. Gadolinium is a contrast taken up for tumours and appears bright white on T1
E. Good for orbital apex lesions
A - B: True; T2 is bright. Orbital fat T1 is bright T2 is dark
C: False; T1 is for normal anatomy and T2 for pathological changes.
D: True; Paramagnetic substance.
E: True

19. Aberrant regeneration of third cranial nerve
A. Trauma or aneurysms may cause it
B. Central or peripheral response may occur
C. Lid may rise on attempted depression, adduction or occasionally abduction
D. Pupil may constrict on attempted adduction, elevation or depression
E. Convergence may occur on attempted elevation
A - E: True
B- Central response involves mass response of damaged nerve resulting in growth to the wrong muscle. Peripheral response abnormal growth of damaged axons may occur locally.
C- Pseudo Graefe’s phenomenon
D- Pseudo Argyll Robertson pupil.
Widening of palpebral fissure on adduction and narrowing on abduction- Inverse Duane

20. Injury to occipital poles may result
A. Altitudinal defects
B. Upper portion damage leads to entire inferior field of vision
C. Lower portion damage is usually managed conservatively
D. Homonymous paramacular scotoma is the normal area adjoining the scotoma
E. Riddoch phenomenon is characterized by dense homonymous hemianopia in which stationary object is not perceived but a small moving object can be perceived.
A-B: True

C: False; associated with laceration of dural sinuses and results in intracranial bleeding and is fatal.
D: False, this area is characterized by defect for colour and emphasizes the importance of examining the central fields.
E: True.

21. Occipital lobe lesions are associated with
A. Visual hallucinations
B. Colour field defects
C. Vascular injury
D. Cortical blindness
E. Macular sparing
A-E: True
A- Visual hallucinations though can occur from any part of visual system and not specific to occipital lobe. But hallucinations in occipital lobe are unformed (scintillating scotoma)
B- Cerbral dyschromatopsia
Select group of cells involved in colour stimuli are involved
Colour defect is random and does not fall into deuteran/protan types
Make errors while reading pseudo isochromatic plates of Ishihara/ colour sorting
Vascular insult is the most common cause
D- Cortical blindness
Loss of all sensations including dark and light adaptation
Loss of menace reflex
Normal pupillary reaction (pupil pathway is related to third nerve)
Normal extraocular motility
Normal fundus
Hypoxia to the striate cortex is the main cause.
No associated CNS manifestations like motor/sensory/speech disorders

22. Error with Goldmann applanation tonometer
A. Thin corneas produce falsely low readings
B. Thick cornea due to oedema produce low readings
C. For every 3D of increase in corneal power the IOP increases by 1mm Hg
D. Marked corneal astigmatism will produce an elliptical area of contact.
E. For every 4D of increase in astigmatism the IOP increases by 1mm Hg
A-E: True
When biprism is in the usual orientation, with mires horizontally, IOP will be underestimated for with-the rule astigmatism and overestimated for against the rule astigmatism. To minimize this error, the biprism may be rotated until the dividing line between the prisms is 45* to the major axis of the ellipse or an average of vertical and horizontal readings may be taken.

23. Biometry in special conditions
A. Immersion technique is the method of choice in aphakes.
B. Pseudophakic eyes needing IOL exchange have extremely high spikes at the lens followed by reduplication of echoes.
C. System gain is increased in eyes with silicone oil
D. IOL required by eyes with silicone oil is usually 2-3D weaker than indicated by standard power calculation
E. In paediatric biometry in children less than 6 months of age undercorrection has to be done by 60-75% to account for myopic shift later in life.
A-C: True; Newer biometry machines have options for aphakic/ pseudophakic modes
In an aphakic eye sound travels at the speed of 1532m/s and in a phakic eye at 1550m/s.
In a pseudophakic eye sound speed depends on sound transmission characteristic and centre thickness of IOL
Holladay formula for pseudophakic biometry
True axial length = 0.988 apparent axial length +thickness of IOL(1-1532/velocity of sound in IOL)
TAL= 0.988(AAL)+T(1-1532/V)
Velocity of sound in silicone oil is 990m/s
Shammus formula for a cataractous lens with silicone oil
TAL=1133/1550 AAL
Further adjustment for IOL power is required as silicone oil causes a hyperopic shift in aphakic eye.
D: False; stronger lens is required
E: True
For every 1mm axial length the IOL power needs to be increased by +2.5 (considering +23.0 as adult standard)
70% undercorrection of the extra power

24. Wollaston prism
A. Incorporated in the viewing telescope of the keratometer.
B. Consists of two rectangular quartz prisms cemented together.
C. Quartz prisms allow two emergent beams by a fixed angle
D. Dispersion by two prisms causes image blurring
E. Corneal curvature is measured by distance between the mires when the doubled images of the prism just touch
A-C: True; D: False; cancel dispersion of each other allowing sharp images
E- True

25.Javal Schiotz keratometer
A. Calibration is in terms of corneal radius of curvature and not dioptric refracting power of cornea
B. Each step of mire is equivalent to 1D of corneal power
C. In an astigmatic cornea two images are displaced vertically in all meridians of cornea
D. Measures axis of astigmatism as well as its magnitude
E. The mires of Haag- Streit Javal Schiotz incorporate avertical line to facilitate horizontal alignment.

A: False; Also includes dioptric refracting power of cornea.
B. True
C. False; Except in two principal meridians where there is no displacement.
D. True
E. False; Horizontal line for vertical alignment.

26. Fresnel prism/lenses
A. Sheets of polyvinyl chloride, 1mm thick with an refractive index equal to that of crown glass
B. Available in the range between +1 to +20D and -1 to -14 D
C. Patched on the convex surface of lens wetting both surfaces.
D. Temporary trial prisms to evaluate prism corrections for heterophoria
E. Temporary management of recovering muscle paresis.
A-B: True; also 30D, and 25- 18D.
C: False; D-E: True

27. Absorptive lenses
A. Clear crown glass transmits 20% of the UV overall.
B. Clear crown glass increases transmission towards visible spectrum (85% at 350nm)
C. CR-39 no UV transmission at 350 nm and 35% at 375 nm
D. UV filter coatings block all UV rays below 400 nm
E. Glass and CR-39 transmit highly in near IR
A - E: True

28. Anti reflective coatings (ARC)
A. Film of manganese fluoride in a thickness one quarter the wavelength of light
B. Improves light transmission to 100% based on wavelight interference
C. Greatest effect in red green region
D. Coating reduces glare, “ghost veiling” in plus lenses and visibility of thick edge in minus lenses.
E. Reduces shiny appearance of high index glass and plastic lenses
A: False; Magnesium chloride
B: False; 98%
C: False: Yellow green region of spectrum
D- E: True

29. Tinted lenses
A. Pink lenses transmit at high end of spectrum. Comfortable under fluorescent lighting
B. Green good absorption at both ends of spectrum, protect against UV and IR
C. Gray produces maximum colour distortion
D. Brown produces “warm” appearance
E. Yellow tints used for outdoor activities
A: True
B: True; maximum transmission is at luminosity peak of photopic spectrum
C: False; Least distortion
D: True
E: True
No Infra red (NoIR) absorptive lenses absorb between UV 400nm to IR 800 to 1500nm. Their light transmission is variable from 1-40%. Available in gray and yellow colours.

30. Intraocular lens
A. Harold Ridley performed the first successful surgical operation
B. A + 20D lens tilt of 10* induces an astigmatism of 2D
C. Contrast decreases in linear fashion as the amount of implant dislocation increases.
D. A +20D lens in air is 3 times its power in aqueous
E. Magnifying power in air is 15x
A. True
B. True
C. True
D. True;
E. True
If the IOL tilts, a refractive astigmatism results. The effect of tilting IOLs was measured in the laboratory using laser beams. Tilting of the lens caused a spherical error in addition to any astigmatic error. The spherical error was always in the plus direction and, with higher degrees of tilting, became larger than the astigmatic error. With a 20-D lens, a 10° tilt resulted in an increase of spherical power of about 1 D and an astigmatic error of 2 D; a 20° tilt increased spherical power about 4 D; and a 30° tilt increased spherical power about 12 D, increasing astigmatic error to 6.5 D.

31. A compound microscope is used in
A. Slit lamp
B. Keratometer
C. Pachymeter
D. Applanation tonometer
E. Gonioscopy lens
A-E: True

32. Regarding compound microscope
A. Consists of two concave lenses for objective and eye piece
B. Object to be studied is placed just outside the anterior focal length
C. Real, inverted, magnified image is formed behind the objective
D. Porro prisms are incorporated to obtain an erect, non inverted image and also to shorten the physical length of the instrument
E. Zoom lens allows for smooth change in magnification without change in position of object or image.
A: False; convex lens
B-E: True

33. Regarding Hruby lenses
A. used to examine the posterior vitreous and fundus with slit lamp biomicroscope
B. Powerful plano convex lens having a -58.6D
C. Forms virtual, erect, diminished image of the retina
D. Lens placed with plano surface towards the eye.
E. Best view is obtained with lens near the eye, when retinal image is found in pupillary plane.

A: True
B: False; Plano concave
C: True
D: False; Concave surface
E: True

34. Regarding Bausch and Lomb keratometer
A. Principle of constant object size and variable image size
B. Object is a circular mire with one plus and two minus signs
C. Contains 4 aperture diaphragm and two doubling prisms
D. Image doubling is unique in that it is produced side by side as well as 90* from each other.
E. Rotation is required to measure the power of cornea in other principal meridian
A: True
B: False; Two plus and two minus
C: True
D: True
E: False; -One position keratometer. In oblique astigmatism the entire instrument need to be rotated until + signs are aligned.

35. Regarding keratometers
A. The range is 36-52 D (6.5-9.38mm)
B. By interposing a lens of -1D and +1.25 D the lower limit can be extended to 30D (5.6mm) and upper limit to 61 D(10.9mm)
C. Useful in calculation of IOL power
D. Very accurate in flat or steep cornea
E. Measure refractive status in central 3mm cornea.
A-C: True
D: False
E: True

36. Regarding Goldman contact lens
A. Plano concave contact lens with higher RI compared to eye
B. Equatorial mirror(longest and oblong) enables visualization from 30* to equator
C. Smaller the mirror more peripheral the view
D. Illumination column of the slit lamp is always tilted except for viewing 12’o clock fundus (mirror at 6’0 clock)
E. For a more peripheral view of retina, tilt the lens to opposite side and ask the patient to move the eyes to the same side.
A-E: True
For a 12’oclock view , tilt lens down and patient looks up

37. Argon blue-green laser
A. Mixture of 70%(488 nm blue) and 30%(514 nm green) light
B. Argon green well absorbed by melanin and haemoglobin
C. Argon green contra indicated in macular area as it is absorbed by inner retinal layers
D. Scattering of laser light by crystalline lens in elderly necessitates higher power settings
E. Newer lasers are air cooled and limit emission to green
A,B: True
C: False; Argon blue, green is not absorbed
D,E: True

38. Diode lasers
A. 810 nm, infra red, continuous wave mode by semiconductor chip
B. Light is absorbed by melanin
C. Good for oedematous retina and also penetrates sclera
D. Photocoagulation enhanced by ICG with an absorption peak of 800- 810 nm
E. Used in endoscopic DCR
A-E: True

39. Nd:YAG laser
A.1064 infra red, usually continuous wave, but Q switched when used in the eye.
B. Laser energy emitted from neodymium molecules suspended in clear YAG crystal
C. Invisible laser, requires Helium-Neon aiming beam(632.8nm)
D. Photodisruption of capsule
E. Laser beam and aiming beam focused at same spot before starting
A-E: True

40. Blepharophimosis syndrome
A. Autosomal dominant with moderate to severe ptosis
B. Poor levator function, amblyopia is a possibility
C. Short horizontal palpebral fissure
D. Telecanthus, epicanthus inversus and lateral ectropion of lower lid
E. Poorly developed nasal bridge and hypoplasia of superior orbital rims
A-E: True


I made these MCQ's while reading and with the hope I can remember very well next time I revise..