Diseases of the Conjunctiva Practice Questions

Q: Schirmer's test is done for:

Dry eye. **Explanation:** **Schirmer’s test** is the gold-standard bedside clinical test used to evaluate **tear production** (aqueous tear deficiency). It is primarily indicated for the diagnosis of **Dry Eye (Keratoconjunctivitis Sicca)**. The test involves placing a specialized filter paper (Whatman filter paper No. 41, 5mm x 35mm) in the lower fornix at the junction of the lateral one-third and medial two-thirds of the eyelid. * **Schirmer I:** Measures total secretion (reflex + basal) without anesthesia. Normal is >15mm in 5 minutes. <5mm is diagnostic of dry eye. * **Schirmer II:** Measures reflex secretion by irritating the nasal mucosa. **Analysis of Incorrect Options:** * **Epiphora:** This refers to the overflow of tears due to anatomical obstruction of the lacrimal drainage system. It is evaluated using the **Jones Dye Test** or Lacrimal Syringing, not Schirmer’s. * **Dacryocystitis:** This is an infection of the lacrimal sac. Diagnosis is clinical (swelling, pain, and regurgitation on pressure over the sac area). * **Myopia:** This is a refractive error where light focuses in front of the retina. It is diagnosed via **Retinoscopy** or subjective refraction. **High-Yield Clinical Pearls for NEET-PG:** * **Basic Secretion Test:** Performed after topical anesthesia to measure only basal secretion (useful in Sjogren’s syndrome). * **Tear Film Break-up Time (TBUT):** Measures tear film stability. Normal is 15–35 seconds; <10 seconds indicates tear film instability. * **Rose Bengal/Lissamine Green Stains:** Used to identify devitalized conjunctival and corneal epithelial cells in severe dry eye. * **Phenol Red Thread Test:** A faster alternative to Schirmer’s (takes 15 seconds).

Q: What is the term for an infection of an eyelash follicle?

Stye. ### Explanation **Correct Answer: A. Stye (Hordeolum Externum)** A **stye**, or external hordeolum, is an acute, focal, pyogenic inflammation of the **eyelash follicle** and its associated glands (Glands of Zeis or Moll). It is most commonly caused by *Staphylococcus aureus*. Clinically, it presents as a painful, red, and swollen lump at the eyelid margin, which often points outwards and may develop a yellow pus head around the base of an eyelash. **Why the other options are incorrect:** * **B. Impetigo:** This is a highly contagious superficial bacterial skin infection (usually *Staph. aureus* or *Strep. pyogenes*) characterized by "honey-colored crusts." While it can affect the skin of the eyelids, it is not an infection of the hair follicle itself. * **C. Boil (Furuncle):** A boil is a deep infection of a hair follicle (folliculitis) that involves the dermis and subcutaneous tissue, typically occurring on the trunk, face, or neck. While a stye is technically a "small boil" of the eyelid, the specific anatomical term for the eyelash follicle infection is a stye. * **D. Carbuncle:** This is a cluster of connected furuncles (boils) that form a multi-headed inflammatory mass with deeper suppuration. It is much larger and more severe than a stye. **High-Yield Clinical Pearls for NEET-PG:** * **Internal Hordeolum:** Infection of the **Meibomian glands**. It points toward the conjunctival side (tarsal plate) rather than the skin. * **Chalazion:** A **painless**, chronic granulomatous inflammation of the Meibomian gland (not an acute infection). * **Treatment:** Most styes are self-limiting. Management includes warm compresses (to aid drainage), topical antibiotic ointments, and epilation of the involved eyelash to facilitate pus discharge.

Q: Which of the following is the likely organism causing ophthalmia neonatorum on the 3rd day of birth?

Neisseria gonorrhoeae. **Explanation:** Ophthalmia neonatorum is defined as conjunctivitis occurring within the first 30 days of life. The most critical factor in identifying the causative organism is the **incubation period** (timing of onset after birth). **1. Why Neisseria gonorrhoeae is correct:** * **Timing:** Gonococcal conjunctivitis typically presents within **2 to 5 days** of birth. Onset on the 3rd day is a classic presentation for this organism. * **Severity:** It is the most hyperacute and vision-threatening form, characterized by profuse purulent discharge, marked chemosis, and a high risk of corneal perforation if not treated urgently with systemic Ceftriaxone. **2. Why the other options are incorrect:** * **Chlamydia trachomatis (B):** This is the most common cause of ophthalmia neonatorum worldwide, but it has a longer incubation period, typically appearing **5 to 14 days** after birth. * **Streptococcus species (C) & Haemophilus influenzae (D):** These are common bacterial causes that usually present between **5 to 10 days** of life. They generally cause a milder, non-specific mucopurulent conjunctivitis compared to Neisseria. **High-Yield Clinical Pearls for NEET-PG:** * **Chemical Conjunctivitis (Silver Nitrate):** Occurs within the **first 24 hours** (usually resolves in 48 hours). * **Herpes Simplex (HSV-2):** Typically presents between **1 to 2 weeks** of life; associated with vesicular skin lesions. * **Prophylaxis:** 0.5% Erythromycin ointment is the standard of care. * **Diagnosis:** Gram stain showing **Gram-negative intracellular diplococci** confirms Neisseria. * **Important Note:** If a neonate has Chlamydial conjunctivitis, always monitor for **Chlamydial pneumonia** (presents with a characteristic "staccato cough").

Q: Pterygium causes visual disturbances due to which of the following?

Astigmatism. **Explanation:** A **Pterygium** is a triangular, fibrovascular proliferation of the subconjunctival tissue that encroaches onto the cornea. It causes visual disturbances primarily through two mechanisms: 1. **Astigmatism (Correct Answer):** As the pterygium grows onto the cornea, it exerts mechanical traction and flattens the horizontal meridian of the cornea. This induces **With-the-Rule (WTR) astigmatism**. Additionally, the pooling of the tear film at the advancing edge of the pterygium can further alter the corneal curvature. 2. **Visual Axis Obstruction:** If left untreated, the pterygium may grow centrally and cover the pupillary area, directly blocking the light path. **Why other options are incorrect:** * **Myopia & Hypermetropia:** These are axial or refractive errors primarily related to the length of the eyeball or the resting power of the lens. While a pterygium changes the corneal shape, it specifically causes an irregular or meridional change (astigmatism) rather than a uniform spherical shift. * **Keratoconus:** This is a non-inflammatory ectatic dystrophy characterized by progressive thinning and cone-like bulging of the cornea. While both involve corneal distortion, their etiologies are entirely distinct. **High-Yield Clinical Pearls for NEET-PG:** * **Stocker’s Line:** An iron deposition line seen on the corneal epithelium at the leading edge (head) of a stable pterygium. * **Indication for Surgery:** The most common indication is cosmetic disfigurement, followed by visual impairment (astigmatism or axis encroachment) and restricted ocular motility. * **Surgical Gold Standard:** Excision with **Limbal Conjunctival Autograft (CAG)** is the treatment of choice to minimize the high recurrence rate. * **Prevalence:** More common in the "Pterygium Belt" (tropical regions) due to chronic UV light exposure.

Q: Subconjunctival hemorrhage can occur in all of the following conditions except?

High intraocular tension. **Explanation:** Subconjunctival hemorrhage (SCH) occurs when a small blood vessel under the conjunctiva ruptures, leading to the accumulation of blood in the potential space between the conjunctiva and the episclera. **Why High Intraocular Tension is the Correct Answer:** High intraocular tension (Glaucoma) refers to the pressure **inside** the eyeball (intraocular). Subconjunctival vessels are located on the **outside** of the globe (extraocular). While high intraocular pressure can cause corneal edema or ciliary congestion, it does not cause the rupture of superficial conjunctival vessels. Therefore, it is not a cause of SCH. **Analysis of Incorrect Options:** * **Passive Venous Congestion:** Any condition that increases venous pressure (e.g., coughing, sneezing, vomiting, or strangulation) can cause the fragile conjunctival capillaries to rupture due to back-pressure. * **Pertussis (Whooping Cough):** This is a classic cause of SCH in children. The violent, paroxysmal coughing fits lead to a sudden spike in venous pressure (Valsalva-like maneuver), causing mechanical rupture of the vessels. * **Trauma:** This is the most common cause of SCH. Direct blunt trauma or even minor eye rubbing can cause vessel wall disruption. In cases of head injury, SCH without a posterior limit may indicate a base of skull fracture. **NEET-PG High-Yield Pearls:** * **Appearance:** SCH is typically asymptomatic, bright red, and has a sharp anterior limit but may lack a posterior limit in orbital fractures. * **Management:** It is a self-limiting condition. Blood usually reabsorbs within 7–14 days without treatment. * **Systemic Associations:** Recurrent or bilateral SCH should prompt an investigation into systemic hypertension or bleeding diathesis (e.g., hemophilia, anticoagulant use).

Q: What is the most common cause of low vision in pterygium?

Astigmatism. **Explanation:** **Pterygium** is a triangular, fibrovascular subepithelial ingrowth of degenerative bulbar conjunctiva onto the cornea. It is most commonly seen in individuals with chronic exposure to UV light. **Why Astigmatism is the Correct Answer:** The most common cause of visual impairment in pterygium is **With-the-Rule (WTR) astigmatism**. As the pterygium grows onto the cornea, it exerts mechanical traction and flattens the horizontal meridian of the cornea. This change in corneal curvature leads to significant astigmatism even before the lesion reaches the pupillary axis. If the pterygium continues to grow and covers the visual axis (pupillary area), it can cause a further profound decrease in vision due to direct obstruction. **Analysis of Incorrect Options:** * **B. Retinal Detachment:** This is a posterior segment pathology involving the neurosensory retina and is unrelated to the surface pathology of a pterygium. * **C. Corneal ulcer and perforation:** While a pterygium can cause localized dryness (Dellen), it rarely leads to spontaneous ulceration or perforation unless complicated by severe secondary infection or trauma. * **D. Myopia:** Pterygium affects the corneal curvature (astigmatism) rather than the axial length of the eye or the overall refractive power in a way that induces simple myopia. **High-Yield Clinical Pearls for NEET-PG:** * **Stocking’s Line:** An iron deposition line seen on the corneal epithelium anterior to the head of the pterygium (indicates stability). * **Fuchs’ Flecks:** Small greyish-white opacities seen at the advancing edge. * **Surgical Gold Standard:** Wide excision with **Limbal Conjunctival Autograft (CAG)** is the treatment of choice to minimize recurrence. * **Indication for Surgery:** Visual impairment (astigmatism or pupillary encroachment), cosmetic disfigurement, or restricted ocular motility.

Q: Trantas spots and Herbe's pits are seen in which of the following conditions?

Trachoma. **Explanation:** The correct answer is **Trachoma (Option A)**. Trachoma, caused by *Chlamydia trachomatis* (serotypes A, B, Ba, and C), is characterized by specific clinical features depending on the stage of the disease. * **Herbert’s Pits:** These are pathognomonic for Trachoma. They are shallow, oval, or circular depressions found at the superior limbus. They represent the scarred remains of ruptured limbal follicles. * **Trantas Spots:** These are small, white, elevated dots found at the limbus, consisting of eosinophils and epithelial debris. While classically associated with Vernal Keratoconjunctivitis (VKC), they can also be seen in the limbal form of Trachoma during active inflammation. **Analysis of Incorrect Options:** * **Option B (Following conjunctivitis):** General bacterial or viral conjunctivitis does not typically result in permanent limbal scarring (pits) or specific eosinophilic deposits. * **Option C (Spring catarrh/VKC):** While **Trantas spots** are a hallmark of the limbal form of Spring Catarrh (Vernal Keratoconjunctivitis), **Herbert’s pits** are exclusive to Trachoma. Since the question asks for both, Trachoma is the most accurate clinical association. * **Option D (Glaucoma):** This is a disease of the optic nerve and intraocular pressure; it does not involve the formation of conjunctival follicles or limbal pits. **High-Yield Clinical Pearls for NEET-PG:** * **Arlt’s Line:** Horizontal scarring of the superior palpebral conjunctiva (seen in Trachoma). * **SAFE Strategy (WHO):** **S**urgery, **A**ntibiotics (Azithromycin), **F**acial cleanliness, **E**nvironmental improvement. * **Pannus:** Trachomatous pannus is typically superior and progressive. * **Differential:** If the question only mentions "Cobblestone papillae" or "Shield ulcer," think **Spring Catarrh (VKC)**. If it mentions "Herbert's pits," it is always **Trachoma**.

Question 1

Schirmer's test is done for:

Accepted Answer

Dry eye

Answer

Epiphora

Answer

Dacryocystitis

Answer

Myopia

Question 2

What is the term for an infection of an eyelash follicle?

Accepted Answer

Stye

Answer

Impetigo

Answer

Boil

Answer

Carbuncle

Question 3

Which of the following is true regarding pterygium?

Accepted Answer

Occurs in the interpalpebral fissure, mostly on the nasal side.

Answer

Dual pterygium is located superiorly and inferiorly.

Answer

It is infective in etiology.

Answer

It is not associated with UV radiation.

Question 4

Which of the following is the likely organism causing ophthalmia neonatorum on the 3rd day of birth?

Accepted Answer

Neisseria gonorrhoeae

Answer

Chlamydia trachomatis

Answer

Streptococcus species

Answer

Haemophilus influenzae

Question 5

Pterygium causes visual disturbances due to which of the following?

Accepted Answer

Astigmatism

Answer

Myopia

Answer

Hypermetropia

Answer

Keratoconus

Question 6

What type of epithelium lines the conjunctiva?

Accepted Answer

Stratified non-keratinized squamous

Answer

Pseudostratified

Answer

Stratified columnar

Answer

Transitional

Question 7

Subconjunctival hemorrhage can occur in all of the following conditions except?

Accepted Answer

High intraocular tension

Answer

Passive venous congestion

Answer

Peusis

Answer

Trauma

Question 8

What is the most common cause of low vision in pterygium?

Accepted Answer

Astigmatism

Answer

Retinal Detachment

Answer

Corneal ulcer and perforation

Answer

Myopia

Question 9

Giant papillary conjunctivitis is most commonly caused by?

Accepted Answer

Contact lens wear

Answer

Trichiasis

Answer

LASIK surgery

Answer

L.ASEK surgery

Question 10

Trantas spots and Herbe's pits are seen in which of the following conditions?

Accepted Answer

Trachoma

Answer

Following conjunctivitis

Answer

Spring catarrh

Answer

Glaucoma

Diseases of the Conjunctiva — MCQs

Diseases of the Conjunctiva — MCQs

On this page

Practice by Chapter

Want unlimited practice?