Objectively Structured Clinical Examination (OSCE) in Ophthalmology Amar Agarwal, Athiya Agarwal, Dimple Prakash
INDEX
×
Chapter Notes

Save Clear


Question papers 1 to 25Section 1

zoom view
2
3QUESTION 1
zoom view
  1. What will be the diagnosis of this patient?
  2. Mention two complications that this patient will develop if left untreated.
  3. In this patient what will be the two surgical procedures of choice?
  4. In case of grafting which are the preferred areas of procuring the graft?
    4
ANSWERS
  1. This patient has a cicatrical ectropion.
  2. Two common complications of untreated ectropions are: Corneal exposure keratopathy and keratinisation of conjunctiva.
  3. Two commonly performed surgeries are: For mild cicatrical ectropion – Z or VY plasty and for severe ectropion – split skin grafts of full thickness skin grafts with release of the cicatrix.
  4. Grafts are commonly taken from: Posterior auricular, preauricular and supraclavicular areas.
5QUESTION 2
zoom view
  1. Name the lid signs in thyroid eye disease related to the retraction of the eyelid.
  2. What percentage of patients with Grave's disease develop thyroid eye disease and what is the risk factor involved?
  3. Give the five main clinical manifestation of the disease and state the two stages.
  4. What are the causes of visual loss in a patient with thyroid ophthalmopathy?
6ANSWERS
  1. The three eyelid signs associated with retraction of the lid are: Dalrymple's sign (lid retraction in primary gaze), Kocher sign (staring, frightened look) and von Graefe's sign (slow or restricted descent of the lid on attempted down gaze).
  2. 25 to 50% of patients with Graves’ diseases develop thyroid eye disease. Smoking is the most important risk factor for a Grave's disease patient to develop thyroid eye disease.
  3. The five main clinical characteristics are: Soft tissue involvement, restrictive myopathy, optic neuropathy, and proptosis and lid retraction. The two stages of the disease are: Congestive and fibrotic.
  4. The commonest causes of vision loss in thyroid eye disease are corneal exposure keratopathy and optic neuropathy.
7QUESTION 3
zoom view
  1. What is the imaging shown here?
  2. Name the structures visible.
  3. What is the other imaging technique by which you can see these structures?
  4. What is the advantages and disadvantages of both?
8ANSWERS
  1. The imaging technique is the UBM : Ultrasound biomicroscopy
  2. The structures seen here are the corneoscleral junction, the angle recess, root of the iris and ciliary body with the supraciliary space.
  3. Anterior segment OCT is the other imaging technique by which most of these structures can be seen.
  4. Advantages of UBM:
    • Study of angle recess and beyond like the ciliary body and the supraciliary space and the suprachoroidal space can be done.
    • Tumors of the iris root, ciliary body with extension can be visualized well.
    Advantages of anterior segment OCT
    • Corneal morphological details seen in detail
    • Easy to learn with shorter learning curve
    • Quick non-contact procedure with greater patient comfort.
    • Anterior chamber cells and reactions seen well
    • Vector measurements possible
    • Serial analysis of disease possible with respect to progress due to ability of data storage.
    Disadvantage of UBM
    • Contact method that requires immersion technique causing patient discomfort and cooperation.
    • Takes a long time to carry out
    • Longer learning curve
    • Vector measurement absent, manual measurement needs to be done
    • Corneal and anterior chamber morphological not seen in detail.
    Disadvantage of anterior segment OCT
    • Iris root and beyond like the ciliary body, supraciliary space and suprachoroidal space not viewed with their details.
    • Lesions and tumors situated beyond the angle recess are not seen well.
9QUESTION 4
zoom view
  1. What is the most likely diagnosis in this child? What is the other name for the white reflex / leucocoria that is seen here?
  2. Give the non-infective causes of pseudoglioma.
  3. What is the investigation of choice in this condition? What does the figure show?
  4. Which group does this child belong to and why?
  5. What will be the vision prognosis of this child? What is the treatment offered to this child?
10ANSWERS
  1. This child most likely has retinoblastoma. Leucocoria is also called amaurotic cat's eye.
  2. Pseudoglioma can be caused by congenital defects like large colobomas, PHPV, Norries disease, retrolental fibroplasias.
  3. CT scan is the investigation of choice. The CT scan shows the presence of a intraocular irregular mass extending almost retrolental space with calcification.
  4. The child belongs to group 3 on Rees Ellsworth classification. The reason is because the tumour is single, larger than 10 DD and is situated behind the equator.
  5. The vival prognosis may be poor in this child due to the close approximity to the optic disc. External beam radiation can be thought of before an enucleation.
11QUESTION 5
zoom view
  1. Classify and name the surgical procedure that has been performed here. Between which two anatomical spaces is the channel created?
  2. What is the type of bleb seen here? Give two reasons.
  3. What is the most common cause of failed bleb?
  4. What are the non-surgical and non-laser methods of treatment of bleb failure?
  5. In what way can laser be used in patients post-trabeculectomy? Name the lens and the lasers that can be used during the procedure.
12ANSWERS
  1. A partial thickness filtration surgery called trabeculectomy has been performed. The drainage channel is created between the anterior chamber and the subtenons space.
  2. Overhanging bleb also called over filtering cyst is seen here. It is because
    • It is a localised highly elevated cyst like cavity.
    • There are no engorged surface vessels in the surrounding area.
    • Two reasons are – excessive use of antimetabolites during surgery and excessive cautery during surgery.
  3. The most common cause of bleb failure is subconjunctival fibrosis.
  4. Non-surgical method of bleb failure treatment is digital massage and scleral depression and subconjunctival 5FU injection.
  5. The following lasers with the help of Hoskins lens or Zeiss lens can be used:
    • Nd:Yag, for relieving the block at the internal opening of the fistula
    • Argon laser, for laser suture lysis.
13QUESTION 6
zoom view
  1. What is the name of the implant being put? What are the other types available?
  2. Name the clinical condition for which this procedure is being performed. Give its associated lenticular abnormalities.
  3. Which other important systemic investigation will you order for this patient? Why?
  4. At what age will this patient develop glaucoma and at what percentage?
  5. How will the rudimentary stump of iris cause glaucoma?
14ANSWERS
  1. This implant is called Mocher's implant (Aniridia ring segment).
  2. This patient has Anirida, the associated lenticular changes can be: Subluxation of lens, cataract, congenital lens absence, persistent pupillary membrane.
  3. Ultrasound of the abdomen should be ordered as Wilms' tumour is commonly associated with Anirida due to the deletion of short arm of chromosome 11.
  4. 50 % of patients develop glaucoma and usually found at adolescence and at late childhood.
  5. The rudimentary stump will cause glaucoma by closure of the angle with synechiae as a result of contracture of pre-existing fibres between the stump and the angle bridge.
15QUESTION 7
zoom view
  1. What type of scotoma does this patient have? Name the condition casing this type of visual field defect.
  2. Mention the commonest agents causing this clinical condition.
  3. What will be the treatment in this patient?
  4. Which tests should be done on follow-up of this patient apart from visual fields?
  5. What will be the clinical signs on ophthalmoscopy?
16ANSWERS
  1. This patient has a centroceacal scotoma. The typical condition causing this is toxic optic neuropathy.
  2. Commonest causes of toxic optic neuropathy are: Alcohol and smoking.
  3. The treatment will be withdrawal of the toxic agent followed by injection of 1000 units of hydroxycobalamin for 10 days along with oral Vit B12 and a well balanced diet of proteins.
  4. Colour vision, pupillary reactions and near vision test should be done on follow-up visits.
  5. Optic disc temporal pallor, mild disc oedema and splinter haemorrhages are the optic disc clinical signs.
17QUESTION 8
zoom view
  1. Differential diagnosis of clinical conditions on this B scan picture.
  2. What are the systemic features that can be associated with the above differential diagnosis?
  3. What does the A scan picture of this patient show?
  4. The retinal blood vessels bleed into which areas of the intraocular cavity?
  5. What is the membrane caused by organised blood of vitreous haemorrhage called?
18ANSWERS
  1. Vitreous haemorrhage, vitreous exudates and asteroid hyalosis are the common differential diagnosis of this B scan picture.
  2. The systemic conditions to be thought of in case of vitreous haemorrhage is diabetes mellitus, in case of vitreous exudates systemic causes of uveitis and in case of asteroid hyalosis hypercholesterolemia is to be thought of.
  3. The A scan picture in this patient shows moderate spikes.
  4. The retinal blood vessels bleed into the intragel, into the subretinal space and into the retinal layers.
  5. The organised vitreous haemorrhage blood is called Ochre membrane.
19QUESTION 9
zoom view
  1. Give your diagnosis.
  2. Between which layers of the retina is the fluid accumulated?
  3. What is the vision threatening complication of this patient? Give your reason.
  4. What will be the FFA picture in this patient?
  5. What does the red coloured layer signify and why?
20ANSWERS
  1. This is an OCT showing cystoid macular oedema.
  2. The fluid is accumulated between the outer plexiform layer and the inner nuclear layer.
  3. This patient can develop a lamellar macular hole which will cause a drop in the vision. The reason of a macular hole developing is the presence of large cystic spaces that are seen on the OCT which will coalesce.
  4. The FFA of this patient will show flower pattern appearance due to pooling of the dye causing hyperfluorescence.
  5. The red coloured layer is the layer of RPE and choriocapillaries and it is differentiated because of its property of hyper reflectivity.
21QUESTION 10
zoom view
  1. Describe this fundus photo and give the diagnosis.
  2. Where is the abnormal material deposited and give the reason for it?
  3. What are the risk factors of vision loss in this patient?
  4. Give two features in case of exudative form of the disease.
  5. What will be the FFA picture in this patient?
22ANSWERS
  1. This fundus photo shows loss of RPE pigmentation and atrophic areas showing the underlying Choroidal vessels. The diagnosis is in the favour of Dry ARMD.
  2. The abnormal material is deposited at the level of the Bruch's membrane and it is due to failure of RPE PUMP.
  3. The risk factors of vision loss in this patient will be: Large soft drusen, other eye less vision due to ARMD.
  4. In exudative form there is RPE detachment and choroidal new vessels.
  5. The FFA of this patient will show the presence of hyperfluorescence of choroidal vessels and also window defects.
23QUESTION 11
zoom view
  1. What is the astigmatism in the patient?
  2. Comment on posterior elevation.
  3. Is this patient suitable for lasik surgery? why?
  4. What pattern does the astigmatic map shows?
  5. What do the numbers inside the circle in the lower right map means?
24ANSWERS
  1. −5.0 D @ 29 deg.
  2. The posterior elevation is seen in left upper map by purple color indicating >0.075 mm elevation.
  3. No, because of the ectasia of the anterior and posterior cornea with thinning of the cornea suggestive of keratoconus.
  4. Asymmetric Bow Tie with inferior steepening.
  5. The numbers inside the circle in the lower left map indicate local corneal pachymetry readings in those areas of the cornea.
25QUESTION 12
zoom view
  1. Name the parts of this instrument.
  2. What are the optical constituents of the microscope and of what power?
  3. How many prisms are there in the eye piece and why are they placed there?
  4. After whose name is the illumination system named and give the different types of illuminations used?
  5. What is the angle between the slit lamp and eye piece on indirect illumination and give four uses of this system?
26ANSWERS
  1. The three parts of the slit lamp are: Observation system, illumination system and mechanical system.
  2. The microscope consists of an objective lens and an eye piece. The objective lens is a set of two planoconvex lenses that add up to a power of 20 diopters. The eyepiece is of 10 and 16 diopters.
  3. There are two prisms in the eyepiece; they are there to re-invert the inverted image that is formed.
  4. The illumination system is named after Gullstrand and the methods of illumination are: Diffuse, focal, retro, specular, indirect, sclerotic scatter and oscillatory.
  5. The angle between the slit lamp and the eyepiece should be between 30 and 45 degrees. The indirect method is used for seeing corneal vacuoles, corneal infiltrates, epithelial cells and microcysts of the cornea.
27QUESTION 13
zoom view
  1. Identify this instrument. What is the name of the test done with it?
  2. What law of muscle movement does this test follow? What is the distance at which this test can be done?
  3. Should an accommodative target be used during this test? Give your reason.
  4. How is it placed in front of the eye? What is the end point of the test?
  5. What deviation does this test measure?
28ANSWERS
  1. This is a prism bar. The test is called prism bar cover test or prism bar alternate cover test.
  2. Herring's law of equal innervation is followed during the test. The distances at which this test is done are 33 cm and 6 mt.
  3. An accommodative target should be used during the test. The reason is so that the accommodation of the patient is controlled during squint measurement and accommodation does not bring about a change in the angle of squint.
  4. The prism bar is held in front of one eye with the base in the opposite direction of the squint. The end point during the test is reached when there is no movement of either eye seen or less commonly also when a movement in the opposite direction maybe seen.
  5. It measures the total deviation, i.e. manifest and latent deviation.
29QUESTION 14
zoom view
  1. What is the name of the test done here? What are the findings?
  2. Early glaucomatous changes are seen on which type of visual field testing? Should it be done for this patient?
  3. Which stage of glaucoma does this patient belong to? What will be the most likely visual field of this patient?
  4. What does the black line indicate? What are the two zones and what should be the normal position or pattern of the black line?
  5. What are the other methods of scanning of the optic nerve?
30ANSWERS
  1. The test done here is the optical coherence tomography. It shows the presence of thinning of almost all the quadrants of the nerve fibre layer and the loss of the double hump pattern.
  2. Early visual fields involve testing blue targets on yellow background. It is not recommended in this patient.
  3. This patient belongs to late stage of glaucoma. The patient most likely will have a double arcuate scotoma.
  4. The black line indicates the patients RNFL distribution. The two zones are the red and green, indicating the area of thinning and the normative thickness of the RNFL respectively. The black line should always be above the red zone with a characteristic double hump pattern.
  5. The other methods of scanning in this patient are polarimetry and scanning laser ophthalmoscopy.
31QUESTION 15
zoom view
  1. Describe the fundus and the FFA pictures.
  2. Give your differential diagnosis of this patient.
  3. If this was a bilateral condition mention its causes.
  4. Mention the ocular causes of this condition of the optic nerve head causing secondary swelling.
  5. Mention the conditions causing sudden vision loss in such a patient.
  6. If there was optic atrophy in the other eye then what are the conditions called?
32ANSWERS
  1. This is a fundus picture of the optic nerve head showing blurring of the disc margins, hyperemia of the disc and obliteration of the cup disc ratio. The surrounding area as well as the vessels on the disc appears normal.
    The FFA picture shows hyperfluorescence of the disc.
  2. The differential diagnosis of this patient is: Papilloedema, papillitis, AION, hypertensive optic nerve disease and diabetic optic neuritis.
  3. Bilateral diseases are seen in raised intracranial tension, hypertension, diabetes, thyroid and cavernous sinus thrombosis.
  4. Ocular causes causing secondary disc swelling are:
    • Neuro retinitis and phlebitis
    • Ocular hypotony
    • Ischemic CRVO.
  5. Conditions causing of sudden vision loss in this patient are: AION, Papillitis, and ischemic CRVO.
  6. Optic atrophy in the other eye are called Foster Kennedy syndrome or psuedo Foster Kennedy syndrome.
33QUESTION 16
zoom view
  1. Identify the staining and describe the organism. What is the most likely diagnosis?
  2. What is the color of hypopyon caused by this organism?
  3. Is it motile or non-motile organism?
  4. Mention one pigment released by this organism.
34ANSWERS
  1. The staining used is Gram's staining, the slide shows the presence of pink rod shaped bacilli that are gram-negative, most likely and commonly to be Pseudomonas.
  2. The color of the hypopyon produced is Green.
  3. They are motile organisms.
  4. Pyocynine is the pigment released by them.
35QUESTION 17
zoom view
  1. Describe the clinical photo and give your likely diagnosis.
  2. Mention other aetiologies of similar clinical picture.
  3. Which ganglion will lodge the HZ virus? Which are the branches of the trigeminal nerve that will be affected?
  4. What is the oral treatment of recurrent herpetic eye diseases, mention dosage and period? What is the treatment of scarred eyes and after how long?
  5. Why will a patient get 800 mg of oral Acyclovir five times a day? Give three reasons.
  6. Give the role of steroids topical and oral in treatment of viral keratitis.
36ANSWERS
  1. The clinical photo shows the presence of multiple punctate epithelial and subepithelial lesions involving mostly the anterior layer of the cornea and stroma. The most likely diagnosis is viral keratitis.
  2. Other causes of similar clinical picture are:
    • Staphylococci toxin secondary to blepharitis
    • Chemical toxic epitheliopathy
  3. The HZ virus is lodged in the Gasserian ganglion. The branches of the trigeminal nerve that are involved are supraorbital, supratrochlear, infratrochlear and nasal.
  4. Herpetic recurrent eye disease is treated with oral acyclovir of 400 mg twice a day for six months. Scarred eyes are treated with PTK and PK after a period of one year.
  5. 800 mg of Acyclovir are started for the following reasons:
    • Virus shedding period is decreased
    • Healing is accelerated by 50 %
    • Postherpetic neuralgia is decreased.
  6. Topical steroids cause reduction in the scarring and are indicated in associated uveitis or scleritis. Oral steroids are indicated in third nerve paralysis, proptosis, optic neuritis and disciform keratitis.
37QUESTION 18
zoom view
  1. What is the most likely diagnosis of this clinical picture?
  2. If there is iris distortion crescent how will it be differentiated from an iridodialysis?
  3. What will be the cause of decreased vision?
  4. What is the most suspicious sign seen on the anterior surface of the eye?
  5. Describe the diagnostic picture on the B and A scan.
38ANSWERS
  1. The clinical photo most likely shows an ocular tumour belonging to uveal melanoma with extraocular spread.
  2. The iris distortion crescent of a tumour will be differentiated from iridodialysis with the absence of red reflex on transillumination and also absence of H/o of trauma.
  3. The cause of decreased vision will be displacement and distortion of lens as well as ciliary muscle malfunction.
  4. The anterior surface shows the presence of Sentinel vessels which are the dilated perforating branches of the anterior ciliary arteries.
  5. B scan picture shows a classic mushroom shape with A scan showing rapid attenuation of signals and large angle Kappa.
39QUESTION 19
zoom view
  1. Which laser is used in intralase and what is its wavelength?
  2. Give 3 etiological factors for diffuse lamellar keratitis.
  3. Describe 2 advantages of intralase over microkeratome.
  4. Mention 3 patterns of corneal graft edges made by intralase.
40ANSWERS
  1. Laser used is Nd: YLF, wavelength is 1053 nm.
  2. Common causes of DLK are: Meibomitis, bacterial endotoxin, marker ink, microkeratome blade debris, preservatives in drops, interface hemoglobin.
  3. The advantages of intralase are: can make thinner flaps, less flap complication, and uniform depth of flaps possible without the meniscus shape.
  4. The patterns of corneal grafts that are possible with intralase are: Mushroom pattern, zigzag pattern, top hat.
41QUESTION 20
zoom view
  1. What is your complete diagnosis?
  2. Define AC/A ratio. How is it measured?
  3. State the significance of measuring AC/A ratio in this child.
  4. On which examination does the type of surgery to be done depend on, and what are the surgical procedures that can be performed?
  5. How much of esotropia should be surgically corrected? What precaution should be taken before surgery?
42ANSWERS
  1. This child has refractive fully accommodative esotropia.
  2. AC/A ratio is defined as the amount of convergence measured in prism per unit diopter change in accommodation. It is measured by the gradient method and the heterophoria method.
  3. The significance of AC/A ratio is that it helps to know whether the squint is non-refractive accommodative or refractive accommodative squint. Thus it deals with the management of the child.
  4. Examination of squint at distance and at near is important and also the presence of amblyopia should be confirmed. If the deviation is equal for distance and near, then a recession and resection procedure in one eye followed by that of the other eye should be done. If the deviation is greater for near than distance, then bimedial recessions should be done.
  5. The residual squint that is not treatable with glasses should be surgically corrected. Amblyopia should be detected and treated before surgery.
43QUESTION 21
zoom view
  1. Give your diagnosis and the clinical findings in the above picture.
  2. What are the common causes of the condition?
  3. What should be monitored carefully in this patient? State its significance. At what intervals should the follow-up of this patient be placed?
  4. What is the most common cause of isolated nontraumatic third nerve palsy with pupillary involvement?
  5. What are the signs indicative of cavernous sinus syndrome?
44ANSWERS
  1. Complete third nerve paralysis. The patient has complete ptosis, exotropia and defective adduction.
  2. The common causes of this condition are ischemic, trauma, neoplasm and aneurysm.
  3. Pupillary reaction should be carefully monitored. Its significance is that, it is involved in 95% of cases of compressive lesions. It should be monitored every day for the first 5 to 7 days.
  4. The commonest cause of isolated third nerve palsy with pupillary involvement is aneurysm at the junction of the posterior communicating artery with the internal carotid artery.
  5. Presence of involvement of other cranial nerves namely 4, 5 and 6th along with sympathetic plexus involvement is indicative of cavernous sinus syndrome.
45QUESTION 22
zoom view
  1. What is the likely diagnosis? Which variant of neurofibromatosis are they commonly associated with?
  2. Name the two cardinal diagnostics of classic NF1.
  3. Give the other skin associations that can be found in neurofibromatosis.
  4. Which tumour of the optic nerve is associated with neurofibromatosis?
  5. Which clinical picture in patients is commonly associated with glaucoma? Give their percentage.
46ANSWERS
  1. Café au lait spots and NF type 4 (familial café au lait spots) is the variant of neurofibromatosis that these are associated with.
  2. Two cardinal diagnostics of NF are more than 6 café au lait spots and multiple cutaneous neurofibromas.
  3. The other skin associations are: Fibrous molluscum, plexiform neurofibromas and axillary freckles.
  4. Optic nerve glioma is seen in NF cases.
  5. The patients who have upper lid and hemifacial hypertrophy are commonly associated with glaucoma and 50% of patients develop glaucoma.
47QUESTION 23
zoom view
  1. At what distance is this test done and it is used to diagnose which type of strabismus?
  2. What is the lens made up of?
  3. How will you measure the amount of deviation with this test?
  4. What is Maddox groove? What is it used for?
48ANSWERS
  1. This test is done at a distance of 5 to 6 mts. The test diagnoses phorias.
  2. The lens is made up of 5 to 6 cut cylinders.
  3. The amount of deviation is measured by using the tangent screen or by the strength of prisms placed before the eye to make the dot appear at the centre of the red line.
  4. Maddox groove is a red disc with deep grooves on its surface and it is used to measure heterophorias for distance.
49QUESTION 24
zoom view
  1. Describe the clinical picture.
  2. In case of malignancy, give your differential diagnosis.
  3. Does this patient have proptosis? If yes, then what type? Give reasons for your answers.
  4. What are the types of biopsy possible in this patient?
  5. If the surgical excision of the lesion causes a moderate defect then how will it be reconstructed?
50ANSWERS
  1. This clinical picture shows involvement of the right upper and lower lid with hyperplasia or a mass causing mechanical ptosis and fullness of the upper and lower fornicial spaces. There is also associated proptosis.
  2. The following are the differential diagnosis in case of malignancy: sebaceous gland carcinoma and squamous cell carcinoma.
  3. Yes the patient has proptosis. It is a non-axial proptosis. The reason for diagnosing proptosis is presence of exotropia with forward displacement of the globe.
  4. The two types of biopsy that are commonly done are incisional and excisional. The incisional biopsy is further classified as punch and shave.
  5. A moderate sized defect will be reconstructed with a semicircular flap of Tenzel.
51QUESTION 25
zoom view
  1. Identify the instrument.
  2. What are the uses of this instrument?
  3. Why is there an angulation present at the tip?
  4. What is the significance of the flat area behind the tip?
  5. Give another example of similar forceps. Give an example of a less traumatic forceps and the reason for its being less traumatic.
52ANSWERS
  1. The instrument is Colibri forceps.
  2. The uses of the instrument are: Holding tissue like corneal and scleral, tying the sutures and fixing the ocular surface tissue while doing surgery.
  3. The angulation is present at the tip so as to facilitate easy manipulation of the tissue.
  4. The flat area behind the tip is to facilitate easy tying of sutures.
  5. A similar forceps is Lims forceps. A less traumatic forceps is Pierce Hoskins; the reason for it being less traumatic is that its two ends appose each other like cups.