FMGE 2018 — Ophthalmology
21 Previous Year Questions with Answers & Explanations
Argon laser trabeculoplasty is done in:
NOT a feature of trachoma:
Constantly changing refractive error is seen in:
The eye in the newborn is:
Pupil in acute iritis is:
What is the true statement about retinoscopy with a plane mirror?
In dacryocystorhinostomy (DCR), Lacrimal sac opens into:
Cause of sudden loss of vision in a diabetic is due to:
Obstacles in concomitant squint are:
Keratometry is done to assess:
FMGE 2018 - Ophthalmology FMGE Practice Questions and MCQs
Question 1: Argon laser trabeculoplasty is done in:
- A. Secondary glaucoma
- B. Angle recession glaucoma
- C. Angle closure glaucoma
- D. Open angle glaucoma (Correct Answer)
Explanation: ***Open angle glaucoma*** - **Argon laser trabeculoplasty (ALT)** is primarily used in **open-angle glaucoma** to improve aqueous humor outflow through the **trabecular meshwork**. - It creates **small burns** in the trabecular meshwork, increasing permeability and lowering **intraocular pressure (IOP)**. *Secondary glaucoma* - This is a broad category of glaucoma caused by other eye conditions or systemic diseases, and the specific treatment depends on the underlying etiology. - While ALT might be considered in some types of **secondary open-angle glaucoma**, it is not a primary or universal treatment for all secondary glaucomas. *Angle recession glaucoma* - This type of glaucoma occurs after blunt trauma to the eye, causing a tear in the **ciliary body** and widening of the **ciliary body band**. - ALT is generally **ineffective** in angle recession glaucoma because the damage to the trabecular meshwork is structural and not amenable to laser modification. *Angle closure glaucoma* - In **angle-closure glaucoma**, the iris blocks the drainage angle, preventing aqueous outflow. - Treatment typically involves **laser peripheral iridotomy** to create a hole in the iris, or surgical procedures, to open the angle, rather than laser trabeculoplasty.
Question 2: NOT a feature of trachoma:
- A. Entropion
- B. Corneal opacity
- C. Chalazion (Correct Answer)
- D. Herbert's pits
Explanation: ***Chalazion*** - A **chalazion** is a **lipogranulomatous inflammation** of a **meibomian gland** and is not directly caused by *Chlamydia trachomatis* infection, though chronic inflammation could theoretically predispose to it. - While chronic inflammation of the eyelids in trachoma can cause various complications, a chalazion is a distinct condition related to meibomian gland dysfunction and is not a direct, defining feature of trachoma. *Entropion* - **Entropion**, the **inward turning of the eyelid margin**, is a severe late complication of trachoma caused by conjunctival scarring and contraction. - This inward turning leads to **trichiasis** (**misdirected eyelashes**), which abrades the cornea. *Corneal opacity* - **Corneal opacity** is a common and serious consequence of chronic trachoma, resulting from repeated **corneal abrasions** by misdirected eyelashes (trichiasis) and chronic inflammation. - This scarring can lead to **severe vision impairment** and **blindness**. *Herbert's pits* - **Herbert's pits** are characteristic depressions on the **limbus** (corneoscleral junction) formed after the resolution of **limbal follicles** in chronic trachoma. - They are a diagnostic sign of past or present trachomatous infection.
Question 3: Constantly changing refractive error is seen in:
- A. Morgagnian cataract
- B. Intumescent cataract
- C. Traumatic cataract
- D. Diabetic cataract (Correct Answer)
Explanation: ***Diabetic cataract*** - Fluctuating blood glucose levels in diabetes can cause changes in the **osmolarity of the aqueous humor**, which in turn affects the hydration of the lens and its refractive power. - This leads to a **constantly changing refractive error**, where a person's prescription might change rapidly over short periods of time. *Morgagnian cataract* - This is a type of **hypermature cataract** where the cortex has liquefied, allowing the nucleus to sink within the capsular bag. - While vision is severely impaired, it doesn't typically present with a constantly changing refractive error, but rather a stable, significant vision loss. *Intumescent cataract* - An **intumescent cataract** is a mature or hypermature cataract where the lens has become significantly swollen due to water absorption. - This swelling causes the anterior capsule to stretch, but it results in a fixed and profound vision loss, not a fluctuating refractive error. *Traumatic cataract* - A **traumatic cataract** develops as a result of blunt or penetrating ocular injury, causing damage to the lens fibers. - While the specific type of refractive error can vary depending on the trauma, it typically presents as a stable visual impairment rather than a constantly changing refractive error.
Question 4: The eye in the newborn is:
- A. Hypermetropia (Correct Answer)
- B. Myopia
- C. Hypermetropic with regular astigmatism
- D. Hypermetropic with irregular astigmatism
Explanation: ***Hypermetropia*** - The newborn eye is typically **shorter in axial length** (approximately 16-17 mm vs. 24 mm in adults), leading to a state of **physiological hypermetropia** (farsightedness) of about **+2 to +4 diopters**. - This is a **universal finding** in newborns and represents the most fundamental refractive characteristic of the newborn eye. - The eye gradually grows and typically reaches emmetropia (normal vision) by about **6-7 years of age**. *Myopia* - **Myopia** (nearsightedness) occurs when the eye is too long or the refractive power is too strong, causing light to focus in front of the retina. - Myopia is **not the physiological state** of the newborn eye and is uncommon at birth. - When present in newborns, it may indicate pathology or very premature birth. *Hypermetropic with regular astigmatism* - While **most newborns do have some degree of astigmatism** (0.5-2D) in addition to hypermetropia, typically "against-the-rule" astigmatism that decreases during the first year, the question asks for the **primary refractive characteristic**. - **Hypermetropia alone** is the universal and defining feature, whereas the amount of astigmatism varies considerably between individuals. - In standard clinical terminology, when describing the typical newborn eye, "hypermetropic" is the complete answer. *Hypermetropic with irregular astigmatism* - **Irregular astigmatism** is uncommon and is typically associated with corneal pathology, trauma, or surgery. - It is **not a physiological finding** in the normal newborn eye and would indicate an underlying abnormality if present.
Question 5: Pupil in acute iritis is:
- A. Dilated
- B. Normal
- C. Constricted (Correct Answer)
- D. Vertically oval
Explanation: ***Constricted*** - In acute iritis, the pupil is typically **constricted (miotic)** due to ciliary muscle spasm and release of inflammatory mediators like prostaglandins. - This constriction helps to **reduce photophobia** and pain by limiting the amount of light entering the eye. *Dilated* - A dilated pupil (mydriasis) is usually seen in conditions like **acute angle-closure glaucoma** or due to certain medications, not iritis. - In iritis, the inflammatory process *actively* causes constriction. *Normal* - A normal pupil size would not be expected in acute iritis, as inflammation always causes some degree of **miosis** or other pupillary abnormality. - Acute iritis presents with significant symptoms that affect pupillary function. *Vertically oval* - A vertically oval pupil can be seen in specific conditions such as **acute angle-closure glaucoma** in some individuals, particularly with high intraocular pressure. - It is not a characteristic feature of iritis.
Question 6: What is the true statement about retinoscopy with a plane mirror?
- A. In myopia, the red glow moves in the same direction.
- B. Retinoscopy is done at 1 meter away from the patient. (Correct Answer)
- C. In hypermetropia, the red glow moves in the opposite direction.
- D. In emmetropia, the red glow moves in the opposite direction.
Explanation: ***Retinoscopy is done at 1 meter away from the patient.*** - Retinoscopy is typically performed at a **working distance** of 67 cm or 1 meter, to allow for the examiner to observe the reflex and to incorporate a working distance lens in the final calculation. - A 1-meter working distance requires a **-1.00 D sphere correction** to be subtracted from the spherical power found in retinoscopy to find the patient's actual refractive error. *In myopia, the red glow moves in the same direction.* - In **myopia**, using a plane mirror, the retinal reflex appears to move in the **opposite direction** to the movement of the retinoscope. - This "against" movement needs **concave (minus)** lenses to neutralize it. *In hypermetropia, the red glow moves in the opposite direction.* - In **hypermetropia**, using a plane mirror, the retinal reflex appears to move in the **same direction** as the movement of the retinoscope. - This "with" movement needs **convex (plus)** lenses to neutralize it. *In emmetropia, the red glow moves in the opposite direction.* - In **emmetropia**, the light from the retinoscope is focused on the retina, and the reflex also moves in the **same direction** as the retinoscope (when using a plane mirror) until neutralization. - An **emmetropic eye** theoretically requires no corrective lens, other than the working distance correction, to neutralize the reflex.
Question 7: In dacryocystorhinostomy (DCR), Lacrimal sac opens into:
- A. Supreme meatus
- B. Middle meatus (Correct Answer)
- C. Inferior meatus
- D. Superior meatus
Explanation: ***Middle meatus*** - In **dacryocystorhinostomy (DCR)**, a new connection is created between the lacrimal sac and the **nasal cavity**, specifically directing tears into the middle meatus. - This surgical procedure aims to bypass an obstruction in the **nasolacrimal duct**, allowing tears to drain directly into the nasal passage through this newly formed opening. *Supreme meatus* - The supreme meatus is a **rare anatomical variation**, located superior to the superior meatus, and is not the standard site for lacrimal drainage. - Surgical intervention in DCR does not target this region for tear evacuation. *Inferior meatus* - The **nasolacrimal duct** normally drains into the inferior meatus, but DCR is performed when this duct is **obstructed**. - Connecting the lacrimal sac directly to the inferior meatus is not the typical surgical approach for DCR. *Superior meatus* - The superior meatus receives drainage from the **posterior ethmoid cells** and the **sphenoid sinus**. - It is not the anatomical location for the lacrimal drainage system, nor is it the target for DCR.
Question 8: Cause of sudden loss of vision in a diabetic is due to:
- A. Central retinal vein occlusion
- B. Neovascular glaucoma
- C. Vitreous hemorrhage (Correct Answer)
- D. Central retinal artery occlusion
Explanation: ***Vitreous hemorrhage*** - **Vitreous hemorrhage** is the **most common cause** of sudden, painless vision loss in individuals with **proliferative diabetic retinopathy** - New, fragile blood vessels (neovascularization) on the retina in diabetes can rupture, leading to bleeding into the **vitreous gel** - Patients describe sudden onset of floaters, cobwebs, or a red haze obscuring vision *Central retinal vein occlusion* - **CRVO** causes sudden, painless vision loss with **retinal hemorrhages in all four quadrants** (blood and thunder appearance) - While diabetic patients are at increased risk, vision loss is typically less profound than vitreous hemorrhage - Fundoscopy shows widespread retinal hemorrhages, dilated tortuous veins, and cotton-wool spots *Neovascular glaucoma* - **Neovascular glaucoma** causes **painful** vision loss and elevated intraocular pressure due to new vessel growth on the iris and trabecular meshwork - While associated with diabetes, it usually presents with more **gradual onset** and pain, rather than sudden, painless vision loss - Characterized by rubeosis iridis and elevated IOP *Central retinal artery occlusion* - **CRAO** causes sudden, profound, painless monocular vision loss, often described as a "curtain coming down" - While diabetic patients are at higher risk for CRAO due to generalized atherosclerosis, it typically results in a **cherry-red spot** on the macula - This is usually embolic in nature and less specifically related to diabetic retinopathy itself
Question 9: Obstacles in concomitant squint are:
- A. Sensory obstacles
- B. Motor obstacles
- C. Central obstacles
- D. All of the options (Correct Answer)
Explanation: ***All of the options*** - **Concomitant squint** involves **sensory obstacles** (e.g., amblyopia, eccentric fixation), **motor obstacles** (e.g., muscle imbalance, inadequate fusional vergence), and **central obstacles** (e.g., defective brain processing of visual information). - All these factors interact to cause and maintain the misalignment of the eyes. *Sensory obstacles* - These include conditions like **amblyopia** (lazy eye) due to suppression of the deviated eye's image, and **eccentric fixation**, where the fovea is not used for central vision. - While significant, sensory obstacles alone do not fully explain concomitant squint, as motor and central components are also crucial. *Motor obstacles* - These involve issues with the **extraocular muscles**, such as imbalance in muscle tone, or problems with the **neural control** of eye movements, leading to a deviation that is relatively constant in all gaze positions. - Motor obstacles are a key component but are often influenced by central and sensory factors. *Central obstacles* - These refer to problems within the brain's visual pathways and centers responsible for **fusion**, **vergence**, and maintaining **ocular alignment**. - Defective processing of visual input or an inability to maintain binocular vision can directly contribute to squint, highlighting the brain's role in coordinating eye movements.
Question 10: Keratometry is done to assess:
- A. Corneal thickness
- B. Curvature of cornea (Correct Answer)
- C. Corneal sensation
- D. Corneal endothelium
Explanation: ***Curvature of cornea*** - **Keratometry** is specifically designed to measure the **radius of curvature of the anterior surface of the cornea**. - This measurement is essential for detecting and quantifying **astigmatism** and for fitting **contact lenses** and calculating **intraocular lens (IOL) power**. *Corneal thickness* - **Corneal thickness** is measured by **pachymetry**, not keratometry. - Pachymetry is used to assess conditions like **corneal edema** or prior to certain refractive surgeries. *Corneal sensation* - **Corneal sensation** is tested using a fine wisp of cotton or a **corneal aesthesiometer**. - This evaluates the integrity of the **corneal nerves** and blink reflex. *Corneal endothelium* - The **corneal endothelium** is assessed using **specular microscopy** to evaluate cell count, size, and shape. - This is important for surgical planning and monitoring **corneal dystrophies**.