FMGE 2024 — Ophthalmology

Q: Which of the following topical local anesthetics is commonly used in cataract surgery?

Proparacaine 0.5%. ***Proparacaine 0.5%***- It is an **ester-type** topical anesthetic that provides rapid, short-duration anesthesia essential for preparatory steps (like measuring **intraocular pressure**) and the initiation of cataract surgery. - **Proparacaine** is the highly preferred topical agent in ophthalmology due to its low corneal toxicity and efficacy in anesthetizing the **corneal** and **conjunctival** surfaces. *Bupivacaine 0.5%*- **Bupivacaine** is an **amide-type** anesthetic known for its potent, long-lasting effects, typically utilized for regional or infiltration blocks (e.g., retrobulbar or peribulbar blocks) in the eye, but not standard for topical application alone.- It is less favored than proparacaine for simple topical anesthesia due to potential **corneal epithelial toxicity** if used excessively topically.*Halothane*- **Halothane** is a potent **volatile inhaled general anesthetic** agent used to induce unconsciousness and muscle relaxation during major surgery.- It is not a local anesthetic agent and cannot be used topically to anesthetize the **ocular surface**.*Nitrous Oxide*- **Nitrous oxide** is an **inhalational anesthetic gas** often used for sedation (or as an adjunct to general anesthesia) due to its analgesic properties.- It provides systemic central nervous system effects and is not formulated or used as a **topical local anesthetic** solution for eye surgery. [Practice more Ophthalmology PYQs on OnCourse]

Q: A 32-year-old patient presents with blurred vision, photophobia, and mild ocular pain. Examination reveals aqueous flares and keratic precipitates in the anterior chamber. What is the likely diagnosis?

D. Iridocyclitis. ***D. Iridocyclitis***- **Iridocyclitis** is the preferred term for **anterior uveitis**, which involves inflammation of the iris and ciliary body.- The hallmark signs of **aqueous flares** (protein and cells in the anterior chamber) and **keratic precipitates** (inflammatory cell deposits on the corneal endothelium) confirm that the inflammation is localized to the **anterior chamber**.*A. Intermediate uveitis*- Characterized by inflammation primarily in the **vitreous** and **pars plana**, often referred to as *vitritis*.- While it causes blurred vision and floaters, the anterior chamber signs like *aqueous flares* and *keratic precipitates* are not the dominant features; fundoscopy may reveal **snowbanking**.*B. Posterior uveitis*- Involves inflammation of the **retina** and/or **choroid** (e.g., retinitis or choroiditis), often causing significant central vision loss and scotomas.- The primary findings are located in the posterior segment (fundus lesions), and the anterior chamber is often **quiet** or shows only mild reaction.*C. Toxoplasma uveitis*- This is a specific cause of **posterior uveitis**, typically presenting as a focus of **necrotizing retinitis** adjacent to an old, pigmented scar.- Although it can cause a *secondary* anterior chamber reaction, the primary diagnostic feature is the specific retinal lesion, which is not mentioned in this presentation. [Practice more Ophthalmology PYQs on OnCourse]

Q: Optic nerve glioma is seen in?

A. NF-1. ***NF-1***- **Optic pathway gliomas (OPGs)** are hallmark features of **Neurofibromatosis type 1 (NF-1)**, an autosomal dominant disorder caused by a mutation in the *NF1* gene on chromosome 17.- OPGs are typically low-grade **pilocytic astrocytomas** and commonly present in children under 6 years of age. *Tuberous sclerosis*- The most characteristic CNS tumor in patients with **Tuberous Sclerosis Complex (TSC)** is the **subependymal giant cell astrocytoma (SEGA)**, usually near the foramen of Monro.- TSC is associated with **retinal astrocytic hamartomas** (phakomas), not primary optic nerve gliomas. *NF-2*- **Neurofibromatosis type 2 (NF-2)** is characterized by **bilateral vestibular schwannomas** (acoustic neuromas), which is the diagnostic criterion.- Other common tumors in NF-2 include meningiomas, ependymomas, and other cranial or spinal schwannomas, but rarely **optic nerve gliomas**. *Schwannoma*- A **schwannoma** is a tumor arising from Schwann cells, often seen on peripheral nerves or cranial nerves (like CN VIII in NF-2).- The optic nerve is considered part of the CNS (a tract of the diencephalon) and is myelinated by oligodendrocytes, meaning **schwannomas** are not primary tumors of the optic nerve itself. [Practice more Ophthalmology PYQs on OnCourse]

Q: Conjunctival xerosis is caused by which vitamin deficiency?

Vitamin A. ***Vitamin A***- Vitamin A is crucial for the maintenance and differentiation of **epithelial cells**, including those of the conjunctiva.- Deficiency leads to **xerophthalmia**, starting with **night blindness** and progressing to **conjunctival xerosis** (dryness) and eventual **keratomalacia**.*Vitamin K*- Vitamin K is essential for the hepatic synthesis of **clotting factors** (II, VII, IX, X).- Deficiency results in a **coagulopathy** characterized by **excessive bleeding** and prolonged prothrombin time (PT).*Vitamin C*- Vitamin C (*ascorbic acid*) is vital for the hydroxylation of **proline and lysine** during **collagen synthesis**.- Deficiency causes **Scurvy**, symptomatically involving **fragile capillaries**, **gingival swelling and bleeding**, and impaired wound healing.*Vitamin D*- Vitamin D's primary role is regulating **calcium and phosphate metabolism** to maintain bone health.- Deficiency leads to **Rickets** in children and **Osteomalacia** in adults, primarily affecting the skeletal system. [Practice more Ophthalmology PYQs on OnCourse]

4 Previous Year Questions with Answers & Explanations

Questions

Which of the following topical local anesthetics is commonly used in cataract surgery?

A 32-year-old patient presents with blurred vision, photophobia, and mild ocular pain. Examination reveals aqueous flares and keratic precipitates in the anterior chamber. What is the likely diagnosis?

Optic nerve glioma is seen in?

Conjunctival xerosis is caused by which vitamin deficiency?

FMGE 2024 - Ophthalmology FMGE Practice Questions and MCQs

Question 1: Which of the following topical local anesthetics is commonly used in cataract surgery?

A. Proparacaine 0.5% (Correct Answer)
B. Bupivacaine 0.5%
C. Halothane
D. Nitrous Oxide

Explanation: ***Proparacaine 0.5%***- It is an **ester-type** topical anesthetic that provides rapid, short-duration anesthesia essential for preparatory steps (like measuring **intraocular pressure**) and the initiation of cataract surgery. - **Proparacaine** is the highly preferred topical agent in ophthalmology due to its low corneal toxicity and efficacy in anesthetizing the **corneal** and **conjunctival** surfaces. *Bupivacaine 0.5%*- **Bupivacaine** is an **amide-type** anesthetic known for its potent, long-lasting effects, typically utilized for regional or infiltration blocks (e.g., retrobulbar or peribulbar blocks) in the eye, but not standard for topical application alone.- It is less favored than proparacaine for simple topical anesthesia due to potential **corneal epithelial toxicity** if used excessively topically.*Halothane*- **Halothane** is a potent **volatile inhaled general anesthetic** agent used to induce unconsciousness and muscle relaxation during major surgery.- It is not a local anesthetic agent and cannot be used topically to anesthetize the **ocular surface**.*Nitrous Oxide*- **Nitrous oxide** is an **inhalational anesthetic gas** often used for sedation (or as an adjunct to general anesthesia) due to its analgesic properties.- It provides systemic central nervous system effects and is not formulated or used as a **topical local anesthetic** solution for eye surgery.

Question 2: A 32-year-old patient presents with blurred vision, photophobia, and mild ocular pain. Examination reveals aqueous flares and keratic precipitates in the anterior chamber. What is the likely diagnosis?

A. D. Iridocyclitis (Correct Answer)
B. A. Intermediate uveitis
C. B. Posterior uveitis
D. C. Toxoplasma uveitis

Explanation: ***D. Iridocyclitis***- **Iridocyclitis** is the preferred term for **anterior uveitis**, which involves inflammation of the iris and ciliary body.- The hallmark signs of **aqueous flares** (protein and cells in the anterior chamber) and **keratic precipitates** (inflammatory cell deposits on the corneal endothelium) confirm that the inflammation is localized to the **anterior chamber**.*A. Intermediate uveitis*- Characterized by inflammation primarily in the **vitreous** and **pars plana**, often referred to as *vitritis*.- While it causes blurred vision and floaters, the anterior chamber signs like *aqueous flares* and *keratic precipitates* are not the dominant features; fundoscopy may reveal **snowbanking**.*B. Posterior uveitis*- Involves inflammation of the **retina** and/or **choroid** (e.g., retinitis or choroiditis), often causing significant central vision loss and scotomas.- The primary findings are located in the posterior segment (fundus lesions), and the anterior chamber is often **quiet** or shows only mild reaction.*C. Toxoplasma uveitis*- This is a specific cause of **posterior uveitis**, typically presenting as a focus of **necrotizing retinitis** adjacent to an old, pigmented scar.- Although it can cause a *secondary* anterior chamber reaction, the primary diagnostic feature is the specific retinal lesion, which is not mentioned in this presentation.

Question 3: Optic nerve glioma is seen in?

A. A. NF-1 (Correct Answer)
B. B. Tuberous sclerosis
C. C. NF-2
D. D. Schwannoma

Explanation: ***NF-1***- **Optic pathway gliomas (OPGs)** are hallmark features of **Neurofibromatosis type 1 (NF-1)**, an autosomal dominant disorder caused by a mutation in the *NF1* gene on chromosome 17.- OPGs are typically low-grade **pilocytic astrocytomas** and commonly present in children under 6 years of age. *Tuberous sclerosis*- The most characteristic CNS tumor in patients with **Tuberous Sclerosis Complex (TSC)** is the **subependymal giant cell astrocytoma (SEGA)**, usually near the foramen of Monro.- TSC is associated with **retinal astrocytic hamartomas** (phakomas), not primary optic nerve gliomas. *NF-2*- **Neurofibromatosis type 2 (NF-2)** is characterized by **bilateral vestibular schwannomas** (acoustic neuromas), which is the diagnostic criterion.- Other common tumors in NF-2 include meningiomas, ependymomas, and other cranial or spinal schwannomas, but rarely **optic nerve gliomas**. *Schwannoma*- A **schwannoma** is a tumor arising from Schwann cells, often seen on peripheral nerves or cranial nerves (like CN VIII in NF-2).- The optic nerve is considered part of the CNS (a tract of the diencephalon) and is myelinated by oligodendrocytes, meaning **schwannomas** are not primary tumors of the optic nerve itself.

Question 4: Conjunctival xerosis is caused by which vitamin deficiency?

A. Vitamin K
B. Vitamin C
C. Vitamin D
D. Vitamin A (Correct Answer)

Explanation: ***Vitamin A***- Vitamin A is crucial for the maintenance and differentiation of **epithelial cells**, including those of the conjunctiva.- Deficiency leads to **xerophthalmia**, starting with **night blindness** and progressing to **conjunctival xerosis** (dryness) and eventual **keratomalacia**.*Vitamin K*- Vitamin K is essential for the hepatic synthesis of **clotting factors** (II, VII, IX, X).- Deficiency results in a **coagulopathy** characterized by **excessive bleeding** and prolonged prothrombin time (PT).*Vitamin C*- Vitamin C (*ascorbic acid*) is vital for the hydroxylation of **proline and lysine** during **collagen synthesis**.- Deficiency causes **Scurvy**, symptomatically involving **fragile capillaries**, **gingival swelling and bleeding**, and impaired wound healing.*Vitamin D*- Vitamin D's primary role is regulating **calcium and phosphate metabolism** to maintain bone health.- Deficiency leads to **Rickets** in children and **Osteomalacia** in adults, primarily affecting the skeletal system.