Diseases of the Lens Practice Questions

Q: All of the following are true about Morgagnian cataract, EXCEPT:

It is an immature cataract. **Explanation:** A **Morgagnian cataract** is a specific form of **Hypermature Senile Cataract (HMSC)**, not an immature one. This distinction is the key to identifying the correct answer. 1. **Why Option A is the correct answer (The Exception):** An immature cataract (IMS) is one where the lens is only partially opaque. A Morgagnian cataract occurs when a mature cataract is left untreated, leading to the total liquefaction of the cortex. Therefore, it is classified as **Hypermature**, making Option A false. 2. **Analysis of other options:** * **Option B:** Due to the degeneration of lens fibers and enzymatic breakdown, the cortex transforms into a **milky white fluid**. The lens essentially becomes a bag containing this fluid. * **Option C:** In the hypermature stage, the lens capsule becomes thickened, and **calcium deposits** (calcific spots) are frequently seen on the anterior capsule. * **Option D:** As the cortex liquefies, it loses its structural support. The heavy, dense, and often brownish-colored nucleus **sinks to the bottom** of the capsular bag due to gravity. **Clinical Pearls for NEET-PG:** * **Iridodonesis:** In Morgagnian cataracts, the lack of cortical support can lead to "tremulousness of the iris." * **Complications:** If the liquefied cortex leaks through the capsule, it can lead to **Phacolytic Glaucoma** (macrophages clog the trabecular meshwork). * **Visual Acuity:** Usually reduced to "Hand Movements" or "Projection of Rays." * **Surgical Note:** During surgery (SICS/Phaco), the "milky" cortex can obscure the view, making the Continuous Curvilinear Capsulorhexis (CCC) challenging (often requiring Trypan Blue dye).

Q: Cataract associated with convulsions is seen in which condition?

Galactosemia. **Explanation:** **Galactosemia** is the correct answer because it is a metabolic disorder characterized by the deficiency of the enzyme **Galactose-1-phosphate uridyltransferase (GALT)**. This leads to the accumulation of galactose and its metabolite, **dulcitol (galactitol)**, in the lens. Dulcitol is osmotically active, drawing water into the lens fibers and causing the classic **"Oil droplet cataract."** Systemically, the accumulation of toxic metabolites leads to liver failure, mental retardation, and **hypoglycemic convulsions** (due to inhibition of glycogenolysis). **Analysis of Incorrect Options:** * **Toxoplasmosis:** Typically presents with the triad of chorioretinitis, hydrocephalus, and intracranial calcifications. While it causes seizures, it does not typically cause congenital cataracts. * **Tay-Sachs Disease:** A lysosomal storage disorder characterized by a **"Cherry-red spot"** at the macula and progressive neurodegeneration. It does not cause cataracts. * **Birth Asphyxia with Prematurity:** This is a major risk factor for **Retinopathy of Prematurity (ROP)** and hypoxic-ischemic encephalopathy (causing seizures), but it is not a primary cause of congenital cataract. **High-Yield Clinical Pearls for NEET-PG:** * **Oil Droplet Cataract:** Pathognomonic for Galactosemia. * **Reversibility:** Galactosemic cataracts are among the few types that can be **reversed** if a lactose-free diet is initiated early. * **Sunflower Cataract:** Seen in Wilson’s Disease (Copper deposition). * **Snowflake Cataract:** Seen in Diabetes Mellitus. * **Christmas Tree Cataract:** Seen in Myotonic Dystrophy.

Q: Which of the following types of cataract is most commonly associated with aging?

Nuclear cataract. **Explanation:** **Nuclear Cataract** is the most common type of age-related (senile) cataract. It occurs due to the progressive intensification of the normal aging process of the lens. As we age, the lens fibers become increasingly compressed and dehydrated at the center (nucleus), leading to **nuclear sclerosis**. This is characterized by the deposition of yellow-brown pigment (urochrome), which increases the refractive index of the lens, often causing a "myopic shift" or "second sight" in elderly patients. **Analysis of Incorrect Options:** * **B. Intumescent cataract:** This is a stage of cataract progression (usually cortical) where the lens becomes swollen due to the osmotic imbibition of water. It is not a primary type associated with aging but rather a complication of the immature stage. * **C. Morgagnian cataract:** This represents a hypermature stage where the cortex liquefies, allowing the heavy, brownish nucleus to settle at the bottom of the capsular bag. This is an advanced stage, not the most common presentation. * **D. Posterior subcapsular cataract (PSC):** While it can occur with age, it is more classically associated with **steroid use**, diabetes mellitus, or ionizing radiation. It causes significant glare and vision loss in bright light. **High-Yield Clinical Pearls for NEET-PG:** * **Second Sight:** A hallmark of nuclear cataract where the myopic shift allows elderly patients to read without glasses again. * **Cupuliform Cataract:** Another name for Posterior Subcapsular Cataract. * **Grading:** Nuclear cataracts are graded based on color (e.g., *Cataracta Brunescens* for brown, *Cataracta Nigra* for black). * **Most common cause of blindness in India:** Cataract (specifically senile).

Q: Rider's cataract is seen in which of the following types of cataracts?

Zonular cataract. **Explanation:** **Zonular (Lamellar) cataract** is the most common type of congenital cataract. It is characterized by opacity involving a specific "zone" or layer of the lens fibers (usually the fetal nucleus), while the embryonic nucleus and the cortex remain clear. The hallmark feature of this condition is **"Riders."** These are linear, U-shaped opacities that extend from the main zone of opacity into the clear cortex, straddling the equator like a rider on a horse. This occurs because the lens fibers formed during the period of metabolic insult become opaque, while those formed before and after remain transparent. **Analysis of Incorrect Options:** * **Blue dot cataract (Punctate cataract):** These are the most common congenital cataracts but are usually stationary and asymptomatic. They appear as small, bluish, rounded opacities scattered throughout the lens. * **Anterior capsular cataract:** These are small, central, white opacities on the anterior lens capsule, often associated with persistent pupillary membranes or intrauterine inflammation. * **Coronary cataract:** This is a form of senile or developmental cataract where club-shaped opacities are arranged in a ring (like a crown) in the peripheral deep cortex, often hidden by the iris. **Clinical Pearls for NEET-PG:** * **Etiology:** Zonular cataracts are frequently associated with **Vitamin D deficiency (Hypocalcemia)** during infancy or maternal infections. * **Visual Impact:** They are usually bilateral and often cause significant visual impairment, frequently requiring surgical intervention. * **Morphology:** Always look for the keyword "linear opacities straddling the equator" to identify Riders.

Q: A 60-year-old male presents with coloured halos. On Fincham's test, the halos split and then reunite. The most probable diagnosis is?

Senile immature cataract. **Explanation:** The presence of colored halos is a classic symptom in ophthalmology, typically caused by the diffraction of light. The **Fincham’s Test** is the definitive clinical maneuver used to differentiate the cause of these halos. **1. Why Senile Immature Cataract is correct:** In an immature cataract, the halos are produced by the **radial arrangement of lens fibers**, which act as a diffraction grating. When a stenopeic slit is moved across the pupil (Fincham’s Test), the halos **split and then reunite**. This "splitting" is pathognomonic for lenticular halos (cataract). **2. Why the other options are incorrect:** * **Acute Congestive Glaucoma:** Halos are caused by **corneal edema** (fluid droplets in the epithelium). Since the edema is uniform and lacks a radial structure, the halos **do not split** during Fincham’s test; they simply disappear or diminish in intensity. * **Open Angle Glaucoma:** This condition is usually asymptomatic in early stages and does not typically present with colored halos unless the intraocular pressure is acutely very high. * **Mucopurulent Conjunctivitis:** Halos here are caused by **mucus flakes** on the corneal surface. These halos are transient and **disappear after blinking** or washing the eyes. **Clinical Pearls for NEET-PG:** * **Glaucomatous Halos:** The blue-violet ring is innermost, and the red ring is outermost. * **Fincham’s Test Result:** * *Splitting:* Lenticular (Cataract) * *No Splitting:* Corneal (Glaucoma) * **Differential Diagnosis of Halos:** Remember the "3 C's": **C**ataract, **C**orneal Edema (Glaucoma), and **C**onjunctivitis (Mucus). * **Stenopeic Slit:** This is the tool used to perform Fincham's test.

Q: Which of the following is true about lens epithelium?

Is deposited as lens fibers. The lens epithelium is a single layer of cuboidal cells located just beneath the anterior lens capsule. Understanding its dynamics is crucial for NEET-PG. ### **Explanation of the Correct Option** **B. Is deposited as lens fibers:** The lens epithelium is metabolically active only in the anterior and equatorial regions. At the **equator (germinal zone)**, these epithelial cells undergo continuous mitosis, elongate, and differentiate into **secondary lens fibers**. These new fibers are deposited layer-upon-layer over the pre-existing ones throughout life. This unique process makes the lens the only organ that never sheds its cells, leading to the increasing density of the lens nucleus with age. ### **Analysis of Incorrect Options** * **A. Contains polygonal cells:** The anterior lens epithelium consists of a single layer of **cuboidal cells**, not polygonal cells. These cells are responsible for the metabolic transport and synthesis of crystallins. * **C. Remains dehydrated:** While the lens maintains a relatively low water content (approx. 66%) to ensure transparency, it is not "dehydrated." It maintains a **state of relative deturgescence** through the active Na+/K+ ATPase pump located primarily in the lens epithelium. ### **High-Yield Clinical Pearls for NEET-PG** * **Posterior Capsule:** There is **no posterior epithelium** in the adult lens (it is used up during embryonic development to form primary lens fibers). This is why the posterior capsule is the thinnest part of the lens. * **Vossius Ring:** A circular ring of pigment on the anterior lens capsule following blunt trauma, corresponding to the pupillary margin. * **Epicapsular Stars:** Remnants of the tunica vasculosa lentis found on the anterior lens surface (congenital anomaly). * **Cataract Pathogenesis:** Abnormal proliferation and migration of epithelial cells toward the posterior pole lead to **Posterior Subcapsular Cataract (PSC)**.

Q: What is the surgery of choice for congenital cataract?

Extracapsular cataract extraction (ECCE). **Explanation:** The management of congenital cataract focuses on providing a clear visual axis to prevent irreversible amblyopia. **Why ECCE is the Correct Answer:** **Extracapsular Cataract Extraction (ECCE)**, specifically via **Lens Aspiration**, is the gold standard. In children, the lens matter is soft and can be easily aspirated. Modern pediatric cataract surgery involves ECCE with **Primary Posterior Capsulotomy (PPC)** and **Anterior Vitrectomy**. This is crucial because, in children, the posterior capsule opacifies (PCO) almost 100% of the time if left intact. For children >2 years of age, ECCE is combined with Posterior Chamber Intraocular Lens (PCIOL) implantation. **Analysis of Incorrect Options:** * **Intracapsular Cataract Extraction (ICCE):** This is **contraindicated** in children. The vitreous is strongly adherent to the posterior lens capsule (Wieger’s ligament). Removing the entire lens capsule would result in massive vitreous loss and high risk of retinal detachment. * **Needling:** An obsolete technique where a needle was used to puncture the capsule to allow aqueous to dissolve the lens. It often led to severe inflammation (phacoanaphylactic uveitis) and secondary glaucoma. * **Discission:** Similar to needling, it involves incising the anterior capsule. While it may be a component of surgery, it is not a complete procedure for cataract removal. **High-Yield Clinical Pearls for NEET-PG:** * **Timing:** Surgery should be done as early as possible (ideally before 6–8 weeks of age) to prevent stimulus-deprivation amblyopia. * **IOL Calculation:** In infants, the eye is under-corrected (hyperopic target) to account for the "myopic shift" as the eye grows. * **Most common cause:** Idiopathic (overall), but **Galactosemia** is a classic metabolic cause (Oil droplet cataract). * **Rubella:** Characterized by "Pearly white nuclear cataract."

Q: Nuclear cataract is associated with which refractive error?

Index myopia. In nuclear cataracts, the central part of the lens (the nucleus) undergoes progressive sclerosis and opacification. This process increases the **Refractive Index** of the lens nucleus. According to the principles of optics, an increase in the refractive index of the lens increases its total dioptric power, causing light rays to focus in front of the retina. This shift is termed **Index Myopia**. **Explanation of Options:** * **A. Index Myopia (Correct):** The hardening and increased density of the nucleus lead to a higher refractive index, shifting the patient’s refraction toward myopia. * **B. Index Hypermetropia:** This occurs when the refractive index of the lens decreases (e.g., in cortical cataracts due to hydration changes) or when the refractive index of the vitreous increases (e.g., in some diabetic states). * **C & D. Axial Myopia/Hypermetropia:** These refractive errors are determined by the **axial length** of the eyeball (too long or too short, respectively), not by changes in the lens density or refractive index. **Clinical Pearls for NEET-PG:** * **Second Sight (Day-sight):** Patients with nuclear cataracts often experience a temporary improvement in near vision (e.g., being able to read without glasses again) due to the induced index myopia. This is a classic "buzzword" for nuclear cataracts. * **Color Perception:** Nuclear cataracts act as a yellow/brown filter, leading to poor blue-color discrimination (cyanopsia). * **Grading:** Nuclear cataracts are graded based on color (from pale yellow to black/brown, known as *Cataracta Brunescens*). * **Contrast:** While nuclear cataracts cause index myopia, **Cortical cataracts** are more commonly associated with an initial shift toward **Index Hypermetropia** due to a decrease in the refractive index of the cortex.

Q: A 55-year-old male presents with vision of 6/12 in both eyes and complaints of glare at night, particularly while driving. What is the most likely diagnosis?

Opacification of the lens. **Explanation:** The correct answer is **Opacification of the lens (Cataract)**. **1. Why Opacification of the lens is correct:** The hallmark symptom described—**glare (photophobia) at night**, especially from oncoming headlights while driving—is a classic presentation of early cataracts, particularly **posterior subcapsular** or **cortical cataracts**. As the lens becomes opaque, it causes light rays to scatter (diffraction) instead of focusing sharply on the retina. This scattering manifests as glare and halos. A visual acuity of 6/12 in a 55-year-old further supports the diagnosis of age-related lens changes. **2. Why other options are incorrect:** * **Diabetic Retinopathy:** Typically presents with blurred vision, floaters, or sudden vision loss (vitreous hemorrhage). While it affects vision, "glare at night" is not its primary or pathognomonic symptom. * **Age-related Macular Degeneration (ARMD):** Patients usually complain of central vision loss, metamorphopsia (distortion of shapes), or a central scotoma. Peripheral vision and light scattering are generally not the initial complaints. * **Corneal Degeneration:** While some corneal pathologies (like Keratoconus or corneal edema) can cause glare, they are less common in a 55-year-old presenting with bilateral 6/12 vision compared to the high prevalence of cataracts in this age group. **Clinical Pearls for NEET-PG:** * **Cataract Types & Symptoms:** Nuclear cataracts often cause "second sight" (myopic shift), while Posterior Subcapsular Cataracts (PSC) cause significant glare and near-vision impairment. * **Glare Test:** The Brightness Acuity Tester (BAT) is used clinically to evaluate the impact of glare on a patient's functional vision. * **Differential for Glare:** Always consider Cataract, Corneal edema, and status post-refractive surgery (LASIK/PRK).

Question 1

All of the following are true about Morgagnian cataract, EXCEPT:

Accepted Answer

It is an immature cataract

Answer

Lens becomes a bag of milky fluid

Answer

Calcium deposits are seen on the lens capsule

Answer

Brown nucleus settles at the bottom

Question 2

Cataract associated with convulsions is seen in which condition?

Accepted Answer

Galactosemia

Answer

Toxoplasmosis

Answer

Tay-Sachs disease

Answer

Birth asphyxia with prematurity

Question 3

Which of the following types of cataract is most commonly associated with aging?

Accepted Answer

Nuclear cataract

Answer

Intumescent cataract

Answer

Morgagnian cataract

Answer

Posterior subcapsular cataract

Question 4

Rider's cataract is seen in which of the following types of cataracts?

Accepted Answer

Zonular cataract

Answer

Blue dot cataract

Answer

Anterior capsular cataract

Answer

Coronary cataract

Question 5

A 60-year-old male presents with coloured halos. On Fincham's test, the halos split and then reunite. The most probable diagnosis is?

Accepted Answer

Senile immature cataract

Answer

Acute congestive glaucoma

Answer

Open angle glaucoma

Answer

Mucopurulent conjunctivitis

Question 6

Which of the following is true about lens epithelium?

Accepted Answer

Is deposited as lens fibers

Answer

Contains polygonal cells

Answer

Remains dehydrated

Answer

None of the above

Question 7

What is the surgery of choice for congenital cataract?

Accepted Answer

Extracapsular cataract extraction (ECCE)

Answer

Intracapsular cataract extraction (ICCE)

Answer

Needling

Answer

Discission

Question 8

What is the recommended treatment modality for a congenital cataract involving the visual axis?

Accepted Answer

Immediate surgical intervention

Answer

Observation and continued monitoring

Answer

Surgical intervention when the child reaches a suitable age

Answer

Administration of mydriatics

Question 9

Nuclear cataract is associated with which refractive error?

Accepted Answer

Index myopia

Answer

Index hypermetropia

Answer

Axial myopia

Answer

Axial hypermetropia

Question 10

A 55-year-old male presents with vision of 6/12 in both eyes and complaints of glare at night, particularly while driving. What is the most likely diagnosis?

Accepted Answer

Opacification of the lens

Answer

Diabetic retinopathy

Answer

Age-related macular degeneration

Answer

Corneal degeneration

Diseases of the Lens — MCQs

Diseases of the Lens — MCQs

On this page

Practice by Chapter

Want unlimited practice?