FMGE 2023 — Ophthalmology

Q: A young person with recurrent seasonal conjunctivitis presents with itchiness and eye-watering. What is the most likely cell involved in the immediate phase of this condition?

Mast cells. ***Mast cells*** - Seasonal allergic conjunctivitis is a classic Type I **hypersensitivity** reaction (IgE-mediated). The immediate phase is mediated by the degranulation of **mast cells** resident in the conjunctiva. - Upon allergen exposure, cross-linking of surface-bound IgE causes mast cells to release potent preformed mediators, notably **histamine**, which directly causes the immediate onset of **pruritus** (itchiness) and vascular leakage (watering).*Eosinophils* - Eosinophils are primarily associated with the **late-phase** allergic response, recruited to the site hours after the initial reaction. - They contribute to chronic inflammation and tissue damage by releasing major basic protein and other toxic mediators.*Neutrophils* - Neutrophils are the hallmark of **acute inflammation** and are typically abundant in **bacterial infections**, which is not the primary mechanism of this seasonal condition. - While present in some inflammatory states, they are not the primary effector cell governing the immediate symptoms of Type I hypersensitivity.*Lymphocyte* - Lymphocytes, particularly T helper type 2 (Th2) cells, are crucial for promoting the B cell synthesis of **IgE** (sensitization phase). - They drive the overall adaptive immune response but do not mediate the rapid, immediate release of mediators responsible for the acute symptoms. [Practice more Ophthalmology PYQs on OnCourse]

Q: Following cataract surgery, a patient comes with complaints of decreased visual acuity. On examination, posterior capsular opacification is seen. What type of laser can be used to treat this condition?

Nd YAG laser. ***Nd YAG laser*** - The **Nd YAG laser** (Neodymium-doped Yttrium Aluminum Garnet) is the gold standard for treating **Posterior Capsular Opacification (PCO)**, which causes secondary visual decline after cataract extraction. - It employs **photodisruption** (a non-thermal process creating plasma) to precisely cut an opening in the opacified posterior capsule, restoring the visual axis (YAG capsulotomy). *Femto laser* - The **Femtosecond laser** is commonly used for creating the corneal flap in **LASIK** or performing certain steps (**capsulotomy**, lens fragmentation) during primary cataract surgery. - It is not typically used for the treatment of *established* PCO as the **Nd YAG** laser procedure is faster, more efficient, and specifically designed for posterior capsule cutting. *Argon fluoride* - **Argon fluoride** is the emission medium for the **Excimer laser**, which operates in the ultraviolet spectrum. - The primary application of the Excimer laser in ophthalmology is **photoablation** of corneal tissue for refractive surgery (e.g., **PRK** and **LASIK**). *Argon* - The **Argon laser** is a thermal laser used primarily for **photocoagulation** in retinal conditions, such as treating **diabetic retinopathy** or performing peripheral iridotomy. - It is unsuitable for PCO treatment because its thermal mechanism would cause unnecessary heat damage to surrounding structures, unlike the non-thermal **photodisruption** of the Nd YAG laser. [Practice more Ophthalmology PYQs on OnCourse]

Q: A 3-year-old child has amblyopia in the right eye. What is the preferred treatment for this child?

Occlusion Therapy. ***Occlusion Therapy*** - This is the **cornerstone treatment** for functional amblyopia in children aged 3 to 7, as the visual system remains plastic and responsive to stimulation during this critical period. - It involves **patching the better-seeing eye** for designated periods to force the use and subsequent strengthening of vision in the amblyopic eye. - Occlusion therapy is most effective when combined with appropriate refractive correction if needed. *Observation* - Amblyopia is a **developmental disorder** requiring timely intervention during the critical period (before age 7-9) to prevent permanent visual loss. - Observation alone will result in **cortical suppression** becoming irreversible, leading to poor long-term visual acuity. - Active treatment is essential; the condition will not resolve spontaneously. *Spectacles with near addition* - **Refractive correction** (spectacles) is an essential adjunct when refractive errors (hyperopia, astigmatism, anisometropia) contribute to amblyopia, but **occlusion therapy remains the primary treatment** for established amblyopia. - Near addition (bifocals) is primarily used to treat **accommodative esotropia**, not as primary amblyopia therapy. - Spectacles alone are insufficient to reverse cortical suppression in functional amblyopia. *Radial keratotomy* - This is an **outdated refractive surgical technique** involving corneal incisions to correct myopia in adults. - It is **absolutely contraindicated** and medically inappropriate for treating amblyopia or refractive errors in a 3-year-old child. - Modern pediatric amblyopia management relies on non-surgical approaches during the critical visual development period. [Practice more Ophthalmology PYQs on OnCourse]

Q: A 70-year-old patient who has been using presbyopia glasses for the past few years can now read the newspaper comfortably without the glasses. What is the most likely diagnosis?

Index myopia. ***Index myopia*** - This classic phenomenon, often referred to as **"second sight,"** is caused by an increase in the refractive index of the crystalline lens nucleus due to early **nuclear sclerosis** (a type of cataract). - The change in refractive index leads to an acquired **myopic shift**, which effectively compensates for the patient's existing **presbyopia**, allowing near vision without reading glasses. *Index hypermetropia* - **Index hypermetropia** (a hyperopic shift) would significantly worsen the patient's near vision, making it even more difficult to read without correction. - It is typically associated with a decrease in the refractive index of the lens, sometimes seen in **cortical cataracts** or in highly unstable blood sugar levels (uncontrolled diabetes). *Regression of presbyopia* - **Presbyopia** is an irreversible, age-related process caused by the progressive hardening of the lens and loss of accommodative power. - A genuine biological **regression** of presbyopia does not occur; the apparent improvement in near vision is always attributable to an index shift toward **myopia**. *None of the above* - This option is incorrect because the sudden improvement in near vision in an elderly patient previously requiring reading glasses is a highly specific clinical sign of **index myopia** due to evolving **nuclear cataract**. [Practice more Ophthalmology PYQs on OnCourse]

Q: A patient presents to you with pain and redness in the right eye following an injury during welding. On examination, the following is observed. Which of the following is the appropriate next step in managing this patient? ![img-12.jpeg](img-12.jpeg)

Removal by 26G needle. ***Removal by 26G needle*** - The image shows a superficial **corneal foreign body**, a common injury in welders. The definitive initial management is the physical removal of the object. - This procedure is typically performed under topical anesthesia using a slit lamp for magnification, with a fine instrument like a sterile **26-gauge needle** or a foreign body spud to gently lift the object from the cornea. *Steroids and antibiotics* - While topical antibiotics are often prescribed *after* the foreign body is removed to prevent infection, they do not address the primary problem, which is the object itself. - The use of **steroids** is generally contraindicated in the presence of a corneal epithelial defect as they can impede healing and increase the risk of a secondary infection, particularly fungal keratitis. *Surgical exploration* - Surgical exploration in an operating room is indicated for suspected **penetrating ocular injuries** or an **intraocular foreign body**, where the object has perforated the globe. - The foreign body in the image appears superficial and is not indicative of a full-thickness injury that would necessitate invasive surgical exploration. *Keratoplasty* - **Keratoplasty**, or a corneal transplant, is a major surgical procedure reserved for severe corneal scarring, opacity, or structural damage that significantly impairs vision. - This is an entirely inappropriate and excessive treatment for a small, superficial foreign body that can be removed with a minimally invasive office-based procedure. [Practice more Ophthalmology PYQs on OnCourse]

7 Previous Year Questions with Answers & Explanations

Questions

A young person with recurrent seasonal conjunctivitis presents with itchiness and eye-watering. What is the most likely cell involved in the immediate phase of this condition?

Following cataract surgery, a patient comes with complaints of decreased visual acuity. On examination, posterior capsular opacification is seen. What type of laser can be used to treat this condition?

A 3-year-old child has amblyopia in the right eye. What is the preferred treatment for this child?

A 70-year-old patient who has been using presbyopia glasses for the past few years can now read the newspaper comfortably without the glasses. What is the most likely diagnosis?

A patient presents to you with pain and redness in the right eye following an injury during welding. On examination, the following is observed. Which of the following is the appropriate next step in managing this patient? ![img-12.jpeg](img-12.jpeg)

Which vitamin deficiency causes xerophthalmia, a condition which causes dry eyes?

Fundoscopy findings are shown in the image below. What is the most likely diagnosis? ![img-41.jpeg](img-41.jpeg)

FMGE 2023 - Ophthalmology FMGE Practice Questions and MCQs

Question 1: A young person with recurrent seasonal conjunctivitis presents with itchiness and eye-watering. What is the most likely cell involved in the immediate phase of this condition?

A. Eosinophils
B. Mast cells (Correct Answer)
C. Neutrophils
D. Lymphocyte

Explanation: ***Mast cells*** - Seasonal allergic conjunctivitis is a classic Type I **hypersensitivity** reaction (IgE-mediated). The immediate phase is mediated by the degranulation of **mast cells** resident in the conjunctiva. - Upon allergen exposure, cross-linking of surface-bound IgE causes mast cells to release potent preformed mediators, notably **histamine**, which directly causes the immediate onset of **pruritus** (itchiness) and vascular leakage (watering).*Eosinophils* - Eosinophils are primarily associated with the **late-phase** allergic response, recruited to the site hours after the initial reaction. - They contribute to chronic inflammation and tissue damage by releasing major basic protein and other toxic mediators.*Neutrophils* - Neutrophils are the hallmark of **acute inflammation** and are typically abundant in **bacterial infections**, which is not the primary mechanism of this seasonal condition. - While present in some inflammatory states, they are not the primary effector cell governing the immediate symptoms of Type I hypersensitivity.*Lymphocyte* - Lymphocytes, particularly T helper type 2 (Th2) cells, are crucial for promoting the B cell synthesis of **IgE** (sensitization phase). - They drive the overall adaptive immune response but do not mediate the rapid, immediate release of mediators responsible for the acute symptoms.

Question 2: Following cataract surgery, a patient comes with complaints of decreased visual acuity. On examination, posterior capsular opacification is seen. What type of laser can be used to treat this condition?

A. Argon
B. Argon fluoride
C. Femto laser
D. Nd YAG laser (Correct Answer)

Explanation: ***Nd YAG laser*** - The **Nd YAG laser** (Neodymium-doped Yttrium Aluminum Garnet) is the gold standard for treating **Posterior Capsular Opacification (PCO)**, which causes secondary visual decline after cataract extraction. - It employs **photodisruption** (a non-thermal process creating plasma) to precisely cut an opening in the opacified posterior capsule, restoring the visual axis (YAG capsulotomy). *Femto laser* - The **Femtosecond laser** is commonly used for creating the corneal flap in **LASIK** or performing certain steps (**capsulotomy**, lens fragmentation) during primary cataract surgery. - It is not typically used for the treatment of *established* PCO as the **Nd YAG** laser procedure is faster, more efficient, and specifically designed for posterior capsule cutting. *Argon fluoride* - **Argon fluoride** is the emission medium for the **Excimer laser**, which operates in the ultraviolet spectrum. - The primary application of the Excimer laser in ophthalmology is **photoablation** of corneal tissue for refractive surgery (e.g., **PRK** and **LASIK**). *Argon* - The **Argon laser** is a thermal laser used primarily for **photocoagulation** in retinal conditions, such as treating **diabetic retinopathy** or performing peripheral iridotomy. - It is unsuitable for PCO treatment because its thermal mechanism would cause unnecessary heat damage to surrounding structures, unlike the non-thermal **photodisruption** of the Nd YAG laser.

Question 3: A 3-year-old child has amblyopia in the right eye. What is the preferred treatment for this child?

A. Radial keratotomy
B. Observation
C. Occlusion Therapy (Correct Answer)
D. Spectacles with near addition

Explanation: ***Occlusion Therapy*** - This is the **cornerstone treatment** for functional amblyopia in children aged 3 to 7, as the visual system remains plastic and responsive to stimulation during this critical period. - It involves **patching the better-seeing eye** for designated periods to force the use and subsequent strengthening of vision in the amblyopic eye. - Occlusion therapy is most effective when combined with appropriate refractive correction if needed. *Observation* - Amblyopia is a **developmental disorder** requiring timely intervention during the critical period (before age 7-9) to prevent permanent visual loss. - Observation alone will result in **cortical suppression** becoming irreversible, leading to poor long-term visual acuity. - Active treatment is essential; the condition will not resolve spontaneously. *Spectacles with near addition* - **Refractive correction** (spectacles) is an essential adjunct when refractive errors (hyperopia, astigmatism, anisometropia) contribute to amblyopia, but **occlusion therapy remains the primary treatment** for established amblyopia. - Near addition (bifocals) is primarily used to treat **accommodative esotropia**, not as primary amblyopia therapy. - Spectacles alone are insufficient to reverse cortical suppression in functional amblyopia. *Radial keratotomy* - This is an **outdated refractive surgical technique** involving corneal incisions to correct myopia in adults. - It is **absolutely contraindicated** and medically inappropriate for treating amblyopia or refractive errors in a 3-year-old child. - Modern pediatric amblyopia management relies on non-surgical approaches during the critical visual development period.

Question 4: A 70-year-old patient who has been using presbyopia glasses for the past few years can now read the newspaper comfortably without the glasses. What is the most likely diagnosis?

A. Index myopia (Correct Answer)
B. Index hypermetropia
C. Regression of presbyopia
D. None of the above

Explanation: ***Index myopia*** - This classic phenomenon, often referred to as **"second sight,"** is caused by an increase in the refractive index of the crystalline lens nucleus due to early **nuclear sclerosis** (a type of cataract). - The change in refractive index leads to an acquired **myopic shift**, which effectively compensates for the patient's existing **presbyopia**, allowing near vision without reading glasses. *Index hypermetropia* - **Index hypermetropia** (a hyperopic shift) would significantly worsen the patient's near vision, making it even more difficult to read without correction. - It is typically associated with a decrease in the refractive index of the lens, sometimes seen in **cortical cataracts** or in highly unstable blood sugar levels (uncontrolled diabetes). *Regression of presbyopia* - **Presbyopia** is an irreversible, age-related process caused by the progressive hardening of the lens and loss of accommodative power. - A genuine biological **regression** of presbyopia does not occur; the apparent improvement in near vision is always attributable to an index shift toward **myopia**. *None of the above* - This option is incorrect because the sudden improvement in near vision in an elderly patient previously requiring reading glasses is a highly specific clinical sign of **index myopia** due to evolving **nuclear cataract**.

Question 5: A patient presents to you with pain and redness in the right eye following an injury during welding. On examination, the following is observed. Which of the following is the appropriate next step in managing this patient? ![img-12.jpeg](img-12.jpeg)

A. Removal by 26G needle (Correct Answer)
B. Keratoplasty
C. Steroids and antibiotics
D. Surgical exploration

Explanation: ***Removal by 26G needle*** - The image shows a superficial **corneal foreign body**, a common injury in welders. The definitive initial management is the physical removal of the object. - This procedure is typically performed under topical anesthesia using a slit lamp for magnification, with a fine instrument like a sterile **26-gauge needle** or a foreign body spud to gently lift the object from the cornea. *Steroids and antibiotics* - While topical antibiotics are often prescribed *after* the foreign body is removed to prevent infection, they do not address the primary problem, which is the object itself. - The use of **steroids** is generally contraindicated in the presence of a corneal epithelial defect as they can impede healing and increase the risk of a secondary infection, particularly fungal keratitis. *Surgical exploration* - Surgical exploration in an operating room is indicated for suspected **penetrating ocular injuries** or an **intraocular foreign body**, where the object has perforated the globe. - The foreign body in the image appears superficial and is not indicative of a full-thickness injury that would necessitate invasive surgical exploration. *Keratoplasty* - **Keratoplasty**, or a corneal transplant, is a major surgical procedure reserved for severe corneal scarring, opacity, or structural damage that significantly impairs vision. - This is an entirely inappropriate and excessive treatment for a small, superficial foreign body that can be removed with a minimally invasive office-based procedure.

Question 6: Which vitamin deficiency causes xerophthalmia, a condition which causes dry eyes?

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

Explanation: **Vitamin A** - It is critical for the differentiation and maintenance of epithelial tissues, including the **conjunctival** and **corneal** epithelium. - Deficiency impairs the eye's ability to produce necessary mucous and results in **xerophthalmia** (pathological dryness of the conjunctiva and cornea) and **night blindness**. *Vitamin B* - Deficiencies in B vitamins (e.g., B1, B2, B3, B12) primarily affect cellular metabolism, causing conditions like **Beriberi** (B1) or **Pellagra** (B3). - While ocular issues like angular blepharitis can occur with deficiencies like Riboflavin (B2), the primary cause of severe **xerophthalmia** is not Vitamin B deficiency. *Vitamin C* - Vitamin C is essential for **collagen synthesis** and acts as a powerful antioxidant. - Its deficiency leads to **scurvy**, characterized by fragile blood vessels, **gingivitis**, and impaired wound healing, unrelated to primary eye dryness or **xerophthalmia**. *Vitamin D* - This vitamin is primarily involved in maintaining **calcium and phosphate homeostasis** for bone health. - Deficiency causes **rickets** in children and **osteomalacia** in adults, systemic conditions that do not cause **xerophthalmia**.

Question 7: Fundoscopy findings are shown in the image below. What is the most likely diagnosis? ![img-41.jpeg](img-41.jpeg)

A. Diabetic retinopathy
B. CRVO
C. CRAO (Correct Answer)
D. Cystoid macular edema

Explanation: ***CRAO*** - The fundoscopy image shows a classic **cherry-red spot** at the macula, which is pathognomonic for Central Retinal Artery Occlusion (CRAO). This spot appears because the fovea receives its blood supply from the underlying choroid, which remains visible and red against the pale, ischemic retina. - CRAO presents as sudden, profound, and painless monocular vision loss. The diffuse retinal pallor is due to edema and ischemia of the inner retinal layers caused by the occlusion of the central retinal artery, often by an **embolus**. *CRVO* - Central Retinal Vein Occlusion (CRVO) is characterized by a "**blood and thunder**" fundus, featuring widespread **retinal hemorrhages**, dilated and tortuous veins, and cotton-wool spots, none of which are present in the image. - Unlike the arterial occlusion seen here, CRVO is a venous outflow obstruction, leading to venous stasis, ischemia, and hemorrhage rather than diffuse retinal pallor. *Diabetic retinopathy* - The fundoscopic findings of diabetic retinopathy include **microaneurysms**, **dot and blot hemorrhages**, **hard exudates**, and **cotton-wool spots** in its non-proliferative stage. - Proliferative diabetic retinopathy is marked by **neovascularization** (new, fragile blood vessel growth) at the disc or elsewhere, which is absent in this image. *Cystoid macular edema* - Cystoid macular edema involves fluid accumulation in the macula, which on fundoscopy may cause loss of the foveal reflex and macular thickening, but not the diffuse pallor or cherry-red spot seen here. - The characteristic finding is a **petaloid pattern** of leakage on fluorescein angiography or cystic spaces on **Optical Coherence Tomography (OCT)**.