NEET-PG 2015 - Ophthalmology Practice Questions

Q: Kayser-Fleischer ring is found in which layer of cornea?

Descemet's membrane. ***Descemet's membrane*** - Kayser-Fleischer rings are caused by **copper deposition** at the periphery of the cornea, specifically within **Descemet's membrane**. - This membrane is located between the **corneal stroma** and the **endothelium**. *Bowman's layer* - Bowman's layer is a thin, acellular layer of the cornea that lies beneath the **corneal epithelium**. - While it plays a role in corneal integrity, it is not the site of **copper deposition** in Wilson's disease. *Corneal stroma* - The corneal stroma is the thickest layer of the cornea, composed primarily of **collagen fibrils**. - Although it contains most of the corneal mass, **copper deposition** in Kayser-Fleischer rings does not specifically occur within the main stromal layer. *Endothelium* - The corneal endothelium is the innermost layer of the cornea, responsible for maintaining **corneal deturgescence**. - While it is adjacent to Descemet's membrane, the copper rings are deposited in the membrane itself, not directly in the endothelial cell layer.

Q: Kayser-Fleischer rings (KF rings) are seen in:

Wilson's disease. ***Wilson's disease*** - **Kayser-Fleischer (KF) rings** are pathognomonic for **Wilson's disease**, resulting from **copper deposition** in the Descemet's membrane of the cornea. - This genetic disorder leads to excessive **copper accumulation** in the liver, brain, and other tissues due to impaired copper excretion. *Pterygium* - A **pterygium** is a benign growth of the **conjunctiva** that extends onto the cornea, typically appearing as a fleshy, triangular lesion. - It is not associated with systemic copper metabolism disorders or the presence of KF rings. *Hemochromatosis* - **Hemochromatosis** is a disorder of **iron overload**, leading to iron deposition in various organs, including the liver, heart, and pancreas. - It does not involve copper metabolism or the formation of corneal rings. *Menke's kinked hair syndrome* - **Menke's syndrome** is a genetic disorder characterized by **copper deficiency**, leading to impaired copper transport and utilization. - It presents with severe neurological deterioration, connective tissue abnormalities, and characteristic **kinky hair**, but not KF rings.

Q: Posterior staphyloma is seen in which condition?

Myopia. ***Myopia*** - A **posterior staphyloma** is an outward bulging of the posterior sclera and choroid, which is a common complication of **high myopia**. - It occurs due to the excessive elongation of the eyeball in myopic eyes, leading to thinning and weakening of the posterior sclera. *Hypermetropia* - This condition involves the eye being too short or the cornea being too flat, causing light to focus behind the retina, and is not associated with posterior staphyloma. - Hypermetropia is typically associated with **smaller axial length** and doesn't lead to the structural changes that cause staphyloma. *Astigmatism* - Astigmatism results from an **irregular curvature of the cornea or lens**, causing light to focus at multiple points on the retina, leading to blurred vision. - It describes a refractive error related to the shape of the optical surfaces, not an outward bulging of the posterior eye wall. *Presbyopia* - This is an **age-related decline in the eye's ability to focus on near objects** due to hardening of the crystalline lens and weakening of the ciliary muscles. - Presbyopia is a normal aging process of the lens and has no association with the structural changes of the posterior sclera seen in staphyloma.

Q: Unilateral frontal blisters with upper lid edema and conjunctivitis is seen in?

Herpes Zoster Ophthalmicus. ***Herpes Zoster Ophthalmicus*** - This condition is characterized by a **unilateral vesicular rash** (blisters) in the **trigeminal dermatome (V1)**, which includes the forehead and upper eyelid, along with significant **lid edema** and **conjunctivitis**. - **Hutchinson's sign** (lesions on the tip, side, or root of the nose) indicates a high risk of ocular involvement due to the nasociliary nerve innervation. *Acanthamoeba Keratitis* - This is an **amoebic infection** of the cornea typically associated with **contact lens wear** and often presents with severe pain and a **ring infiltrate** in the cornea. - It does not typically present with unilateral frontal blisters or significant lid edema. *Herpes Simplex* - Herpes simplex typically causes **recurrent corneal ulcers** (dendritic or geographic) and sometimes blepharitis, but not the widespread **unilateral frontal blisters** seen in the trigeminal distribution. - While it can cause conjunctivitis and lid edema, the pattern of skin lesions is the key differentiator. *Neuroparalytic Keratitis* - This condition results from **trigeminal nerve damage**, leading to corneal anesthesia and subsequent **trophic corneal ulceration**. - It presents primarily with **corneal findings** (epithelial defects, ulcers) due to impaired sensation and tear film stability, not initial vesicular skin lesions or prominent lid edema.

Q: Which organism can penetrate corneal endothelium?

Haemophilus influenzae. ***Haemophilus influenzae*** - *Haemophilus influenzae* is unique in its ability to penetrate the **intact corneal endothelium** through its specific virulence factors and enzymatic mechanisms. - Along with *Neisseria meningitidis*, it can breach the **Descemet's membrane and endothelial barrier** without requiring prior epithelial damage. - This property makes it particularly dangerous as it can cause **endophthalmitis** by directly accessing the anterior chamber. *Neisseria gonorrhoeae* - While highly virulent, *N. gonorrhoeae* penetrates the **corneal epithelium** (outer layer) through its proteases, not the endothelium (inner layer). - It causes severe **hyperacute conjunctivitis** and can lead to **corneal perforation**, but via epithelial destruction and stromal infiltration. *Staphylococcus aureus* - A common cause of **bacterial keratitis** following epithelial defects or trauma. - Causes stromal infiltration and abscess formation but **cannot penetrate intact endothelium**. *Aspergillus fumigatus* - This fungus causes **fungal keratitis** typically after trauma with vegetative matter. - Invades through **epithelial breaches** and stromal infiltration, not through intact endothelial penetration.

Q: All of the following are true about Keratoconus, except:

Thick cornea. ***Thick cornea*** - Keratoconus is characterized by **progressive corneal thinning** and weakening, not thickening. - This corneal thinning leads to a conical protrusion, causing significant visual distortion and irregular astigmatism. *Increased curvature of cornea and Astigmatism* - Keratoconus features **increased corneal curvature** with progressive steepening into a cone-shaped configuration. - This results in **irregular astigmatism**, a hallmark feature causing distorted vision at all distances. *Astigmatism* - **Irregular astigmatism** is a cardinal feature of keratoconus due to the asymmetric corneal shape. - Causes blurred and distorted vision that is difficult to correct with spectacles alone. *Fleischer's ring* - **Fleischer's ring** is an iron deposit ring at the base of the cone in keratoconus, visible on slit-lamp examination. - It represents hemosiderin deposition in the basal epithelial cells and is a characteristic clinical sign of keratoconus.

Q: All of the following are true for sympathetic ophthalmitis except which of the following?

Affects the injured eye. ***Affects the injured eye*** - Sympathetic ophthalmia is a **bilateral, granulomatous panuveitis** that characteristically affects the **fellow, uninjured eye** (sympathizing eye) following trauma or surgery to the other eye (exciting eye). - The disease involves an immune response directed against ocular antigens, typically from the uveal tissue, in the uninjured eye. *Mostly results from a penetrating wound* - This statement is true; **penetrating ocular trauma** (e.g., from surgery or injury) is the most common trigger for sympathetic ophthalmia. - The exposure of uveal antigens from the injured eye initiates an autoimmune response. *Autoimmune etiology* - This statement is true; sympathetic ophthalmia is an **autoimmune disease** mediated by T-lymphocytes against uveal antigens. - The condition is characterized by a delayed hypersensitivity reaction against exposed uveal proteins. *Dalen Fuch's nodules may be seen* - This statement is true; **Dalen-Fuchs nodules** are characteristic histopathological findings in sympathetic ophthalmia. - These are accumulations of epithelioid cells and lymphocytes located between the retinal pigment epithelium and Bruch's membrane.

Q: Where is the intraocular lens placed during cataract surgery?

Capsular bag. ***Capsular bag*** - The **capsular bag** is the natural anatomical space where the human crystalline lens resides and is the ideal location for an intraocular lens (IOL) to mimic the natural lens's position and function. - Placing the IOL in the capsular bag provides **optimal stability**, centration, and reduces the risk of complications such as glare or secondary glaucoma. *Surface of iris* - Placing an IOL on the surface of the iris (**iris-fixated IOL**) is a less common surgical approach, typically reserved for cases where capsular support is absent or insufficient. - This position can lead to potential complications including **iris chafing**, pigment dispersion, and increased risk of uveitis or secondary glaucoma. *Over the face of vitreous* - Placing an IOL over the face of the vitreous typically occurs in cases of **capsular rupture** with inadequate posterior capsule support, requiring anterior vitrectomy and alternative IOL fixation. - This position is less stable and carries a higher risk of **vitreous prolapse**, retinal detachment, and cystoid macular edema compared to capsular bag placement. *Around the limbus* - The limbus is the **junction between the cornea and sclera** and is an entirely incorrect location for an intraocular lens implant. - An IOL around the limbus would be outside the globe and would serve no optical purpose within the eye, leading to **severe visual impairment** and potentially structural damage.

Q: Non foldable lens is made of?

PMMA. ***PMMA*** - **Polymethylmethacrylate (PMMA)** is a rigid, non-foldable material historically used for **intraocular lenses (IOLs)**. - Due to its rigidity, PMMA IOLs require a **larger incision** for implantation, which can lead to astigmatism and slower recovery. *Silicone* - **Silicone** is a flexible, foldable material commonly used for modern IOLs, allowing for **smaller incisions**. - It has excellent **elastic properties** but may be associated with certain risks in eyes with silicone oil. *Acrylic* - **Acrylic** (both hydrophobic and hydrophilic) is a popular material for foldable IOLs, known for its **biocompatibility** and ability to be inserted through small incisions. - It is currently the most widely used material due to its **foldable nature** and good optical qualities. *Hydrogel* - **Hydrogel** is a type of hydrophilic acrylic material, characterized by its **high water content** and flexibility. - While foldable, hydrogel IOLs are less commonly used than other acrylic types, partly due to some concerns about long-term clarity or calcification in certain formulations.

Question 1

Kayser-Fleischer ring is found in which layer of cornea?

Accepted Answer

Descemet's membrane

Answer

Endothelium

Answer

Bowman's layer

Answer

Corneal stroma

Question 2

Kayser-Fleischer rings (KF rings) are seen in:

Accepted Answer

Wilson's disease

Answer

Pterygium

Answer

Hemochromatosis

Answer

Menke's kinked hair syndrome

Question 3

Posterior staphyloma is seen in which condition?

Accepted Answer

Myopia

Answer

Hypermetropia

Answer

Astigmatism

Answer

Presbyopia

Question 4

Unilateral frontal blisters with upper lid edema and conjunctivitis is seen in?

Accepted Answer

Herpes Zoster Ophthalmicus

Answer

Herpes Simplex

Answer

Neuroparalytic Keratitis

Answer

Acanthamoeba Keratitis

Question 5

Which organism can penetrate corneal endothelium?

Accepted Answer

Haemophilus influenzae

Answer

Staphylococcus Aureus

Answer

Aspergillus fumigatus

Answer

Neisseria gonorrhoeae

Question 6

All of the following are true about Keratoconus, except:

Accepted Answer

Thick cornea

Answer

Astigmatism

Answer

Increased curvature of cornea and Astigmatism

Answer

Fleischer's ring

Question 7

All of the following are true for sympathetic ophthalmitis except which of the following?

Accepted Answer

Affects the injured eye

Answer

Mostly results from a penetrating wound

Answer

Autoimmune etiology

Answer

Dalen-Fuchs nodules may be seen

Question 8

Where is the intraocular lens placed during cataract surgery?

Accepted Answer

Capsular bag

Answer

Surface of iris

Answer

Around the limbus

Answer

Over the face of vitreous

Question 9

Non foldable lens is made of?

Accepted Answer

PMMA

Answer

Acrylic

Answer

Hydrogel

Answer

Silicone

Question 10

Rigid gas permeable (RGP) lenses are made from which of the following combinations of materials?

Accepted Answer

Copolymer of PMMA, Silicon containing monomer & cellulose acetyl butyrate

Answer

Hydroxymethylmethacrylate

Answer

Cellulose acetate Butyrate

Answer

Polymethylmethacrylate

NEET-PG 2015 — Ophthalmology