Internal Medicine
3 questionsWhich visual disturbance is commonly associated with Vitamin B12 deficiency?
Ataxia, nystagmus, and ophthalmoplegia are seen in which of the following conditions?
Madarosis is seen in ?
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 641: Which visual disturbance is commonly associated with Vitamin B12 deficiency?
- A. Centrocaecal scotoma (Correct Answer)
- B. Binasal hemianopia
- C. Constriction of peripheral vision
- D. Bitemporal hemianopia
Explanation: No relevant citations could be added to the original explanation because the provided references did not specifically address the association between Vitamin B12 deficiency and centrocaecal scotoma. ***Centrocaecal scotoma*** - **Vitamin B12 deficiency** can lead to optic neuropathy, which often manifests as a **centrocaecal scotoma**, affecting central and paracentral vision. - This visual impairment is due to **demyelination of the optic nerve fibers** caused by the deficiency. *Binasal hemianopia* - This type of visual field defect is rare and typically caused by lesions that compress the uncrossed retinal nerve fibers, such as **bilateral internal carotid artery aneurysms** or **bilateral optic nerve disease**. - It does not directly correlate with **Vitamin B12 deficiency**. *Constriction of peripheral vision* - **Peripheral vision loss** is associated with conditions like **glaucoma** or advanced **retinitis pigmentosa**. - It is not a characteristic visual disturbance of **Vitamin B12 deficiency**. *Bitemporal hemianopia* - This visual field defect is commonly caused by compression of the **optic chiasm**, most often due to a **pituitary adenoma**. - It results in loss of vision in the outer half of both visual fields and is not linked to **Vitamin B12 deficiency**.
Question 642: Ataxia, nystagmus, and ophthalmoplegia are seen in which of the following conditions?
- A. 3rd nerve palsy
- B. Wernicke encephalopathy (Correct Answer)
- C. Myasthenia gravis
- D. Chronic progressive external ophthalmoplegia
Explanation: ***Wernicke encephalopathy*** - This condition is characterized by the classic triad of **ataxia**, **nystagmus**, and **ophthalmoplegia** (often presenting as external ophthalmoplegia), alongside confusion [2]. - It results from a **thiamine (vitamin B1) deficiency** [2], [3], commonly seen in chronic alcoholics or individuals with severe malnutrition. *Myasthenia gravis* - This is an **autoimmune disorder** affecting the neuromuscular junction, leading to fluctuating muscle weakness that worsens with activity [1]. - While it can cause **ophthalmoplegia** (especially ptosis and diplopia), it does not typically present with ataxia or nystagmus. *3rd nerve palsy* - A **third nerve palsy** specifically affects the oculomotor nerve, causing a constellation of symptoms including ptosis, pupillary dilation, and inability to move the eye up, down, or medially. - While it causes **ophthalmoplegia** affecting one eye, it does not typically cause nystagmus or ataxia. *Chronic progressive external ophthalmoplegia* - This is a mitochondrial disorder characterized by **slowly progressive weakness** of the extraocular muscles, leading to bilateral ptosis and limitation of eye movements. - It causes a specific type of **ophthalmoplegia** but is not typically associated with nystagmus or prominent ataxia.
Question 643: Madarosis is seen in ?
- A. None of the options
- B. Addison's disease
- C. Acromegaly
- D. Hypothyroidism (Correct Answer)
Explanation: ***Hypothyroidism*** - **Madarosis**, specifically the loss of the **outer third of the eyebrows**, is a classic sign of **hypothyroidism** due to decreased thyroid hormone levels affecting hair follicle growth [1]. - Other common symptoms include **fatigue**, **weight gain**, **cold intolerance**, and **dry skin**. *Addison's disease* - This condition involves **adrenal insufficiency**, primarily causing symptoms like **hyperpigmentation**, low blood pressure, and fatigue. - **Hair loss** is generally not a prominent feature, and madarosis is not typically seen. *Acromegaly* - Characterized by excessive **growth hormone** production, leading to enlargement of hands, feet, and facial features. - While it can cause some changes in hair texture, **madarosis** is not a common clinical manifestation. *None of the options* - This option is incorrect because **Hypothyroidism** is a direct cause of madarosis due to its impact on **hair follicle metabolism** [1]. - The other conditions listed do not typically present with this specific type of eyebrow hair loss.
Ophthalmology
5 questionsWhich type of cataract is specifically associated with decreased reading ability?
What is the primary mechanism of pathogenesis in acute angle closure glaucoma?
What condition is characterized by cherry red spot at the macula with retinal whitening?
Most common cause of bilateral optic atrophy is:
Massaging of nasolacrimal duct is done in ?
NEET-PG 2012 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 641: Which type of cataract is specifically associated with decreased reading ability?
- A. Blue dot cataract
- B. Nuclear cataract (Correct Answer)
- C. Fusiform cataract
- D. Punctate cataract
Explanation: ***Nuclear cataract*** - **Nuclear cataracts** cause progressive hardening and yellowing of the lens nucleus with increased refractive index - This produces a **myopic shift** that initially causes **"second sight"** (temporary improvement in near vision) - However, as the cataract progresses, the increasing opacity leads to **overall visual decline affecting both distance and near vision**, including reading ability - Among the given options, nuclear cataract is the most common age-related cataract that significantly impairs vision including reading *Blue dot cataract* - **Blue dot cataracts** (cerulean cataracts) are small, bluish peripheral opacities, usually congenital and stationary - They rarely cause significant visual impairment and do not affect reading ability *Fusiform cataract* - **Fusiform cataracts** are congenital spindle-shaped opacities along the visual axis - While they can affect vision if dense, they are rare and not typically associated with progressive reading difficulty *Punctate cataract* - **Punctate cataracts** are small, scattered dot-like opacities in the lens - They are often congenital or age-related and cause minimal visual disturbance - Not specifically associated with decreased reading ability
Question 642: What is the primary mechanism of pathogenesis in acute angle closure glaucoma?
- A. Increased secretion of aqueous humor
- B. Outflow obstruction due to anatomical factors (Correct Answer)
- C. Increased absorption of aqueous humor
- D. Decreased ciliary body function
Explanation: ***Outflow obstruction due to anatomical factors*** - **Acute angle-closure glaucoma (AACG)** occurs due to a sudden blockage of the **trabecular meshwork**, which is the primary drainage pathway for aqueous humor. - This blockage is caused by anatomical predispositions, such as a **narrow anterior chamber angle**, relatively large lens, and **pupillary block** leading to iris bombé with peripheral iris bowing forward. - The iridocorneal angle closure prevents aqueous humor drainage, causing **rapid IOP elevation**. *Increased secretion of aqueous humor* - While increased aqueous humor production can contribute to elevated intraocular pressure, it is **not the primary mechanism** in acute angle-closure glaucoma. - This mechanism is more relevant in **open-angle glaucoma** or conditions with ciliary body overactivity. - AACG's hallmark is **outflow obstruction**, not increased production. *Decreased ciliary body function* - Decreased ciliary body function would **reduce aqueous humor production**, leading to **hypotony** (low IOP), not elevated pressure. - This is the opposite of what occurs in AACG, where IOP rises dramatically due to impaired drainage. - Ciliary body dysfunction is seen in conditions like **uveitis** or post-surgical complications. *Increased absorption of aqueous humor* - **Increased absorption** of aqueous humor would **reduce intraocular pressure**, which is the opposite of what occurs in acute angle-closure glaucoma. - The disease is characterized by a **rapid and severe rise in intraocular pressure** due to impaired outflow, not enhanced absorption. - Normal aqueous absorption occurs via trabecular and uveoscleral pathways, both of which are blocked in AACG.
Question 643: What condition is characterized by cherry red spot at the macula with retinal whitening?
- A. CRVO
- B. CRAO (Correct Answer)
- C. Diabetic retinopathy
- D. Syphilitic retinopathy
Explanation: ***CRAO*** - **Central retinal artery occlusion (CRAO)** is characterized by **sudden, profound, painless monocular vision loss**. - The classic funduscopic finding is a **cherry-red spot at the macula** with diffuse **retinal whitening** due to ischemia. *CRVO* - **Central retinal vein occlusion (CRVO)** presents with **painless vision loss** but typically shows **hemorrhages**, **dilated tortuous veins**, and **cotton wool spots** on funduscopic exam. - It does not usually cause retinal whitening or a cherry-red spot. *Diabetic retinopathy* - **Diabetic retinopathy** is characterized by **microaneurysms**, **hemorrhages**, **hard exudates**, and **cotton wool spots**, and can lead to neovascularization. - It does not present with acute retinal whitening or a cherry-red spot in the macula. *Syphilitic retinopathy* - **Syphilitic retinopathy** can cause a variety of presentations, including **retinal vasculitis**, **chorioretinitis**, and **optic neuritis**. - It does not typically manifest as a cherry-red spot with diffuse retinal whitening at the macula.
Question 644: Most common cause of bilateral optic atrophy is:
- A. Intracranial tumor
- B. Nutritional deficiency (B12/folate) (Correct Answer)
- C. Hereditary optic neuropathy
- D. Toxic optic neuropathy
Explanation: ***Nutritional deficiency (B12/folate)*** - **Nutritional optic neuropathy** due to deficiencies in B vitamins (especially B12, thiamine) and folate is a common cause of bilateral optic atrophy, particularly in **developing countries** and in populations with **malnutrition or chronic alcoholism**. - These deficiencies impair the **metabolism of retinal ganglion cells** and their axons, leading to symmetric bilateral optic nerve degeneration. - The condition is often **reversible in early stages** with appropriate supplementation. - **Note:** The "most common" cause varies by geographic location, population, and clinical setting. *Hereditary optic neuropathy* - **Leber's hereditary optic neuropathy (LHON)** and **autosomal dominant optic atrophy (ADOA)** are major causes of bilateral optic atrophy, especially in **younger patients**. - LHON typically presents in young males (15-35 years) with **sequential bilateral visual loss**. - These are among the **most common inherited optic neuropathies** and should always be considered in bilateral cases. *Intracranial tumor* - Intracranial tumors typically cause **unilateral optic atrophy** due to direct compression of one optic nerve. - **Bilateral optic atrophy** can occur with **chiasmal or suprasellar tumors** (pituitary adenomas, craniopharyngiomas) but is less common. - Usually presents with **visual field defects** (bitemporal hemianopia) before significant atrophy develops. *Toxic optic neuropathy* - **Toxic optic neuropathies** result from exposure to substances such as **methanol, ethambutol, tobacco-alcohol amblyopia**, or isoniazid. - Can cause bilateral symmetric optic atrophy but are **exposure-dependent** and less prevalent in general population. - **Tobacco-alcohol amblyopia** may overlap with nutritional deficiency.
Question 645: Massaging of nasolacrimal duct is done in ?
- A. Acute dacryocystitis
- B. Congenital dacryocystitis (Correct Answer)
- C. Conjunctivitis
- D. None of the options
Explanation: ***Congenital dacryocystitis*** - **Massaging the nasolacrimal duct** (Crigler massage) is a primary treatment for congenital dacryocystitis to promote the opening of the **valve of Hasner**. - This condition is due to incomplete canalization of the nasolacrimal duct, leading to tearing and discharge in infants. *Acute dacryocystitis* - This is an **acute infection of the lacrimal sac**, and massaging can worsen the condition by spreading the infection. - Treatment typically involves **antibiotics** and, if necessary, incision and drainage of any abscess. *Conjunctivitis* - **Conjunctivitis** is inflammation of the conjunctiva and is not related to obstruction of the nasolacrimal duct. - Massaging the nasolacrimal duct has no therapeutic role in treating conjunctivitis. *None of the options* - This option is incorrect because **congenital dacryocystitis** is a condition where nasolacrimal duct massage is a standard and effective treatment.
Pathology
2 questionsOrphan Annie nuclei are characteristic of which of the following?
Which of the following is the most likely proliferating breast mass?
NEET-PG 2012 - Pathology NEET-PG Practice Questions and MCQs
Question 641: Orphan Annie nuclei are characteristic of which of the following?
- A. Paraganglioma with Zellballen pattern
- B. Meningioma with psammoma bodies
- C. Pituitary adenoma with atypical nuclei
- D. Papillary thyroid carcinoma (Correct Answer)
Explanation: ***Papillary carcinoma thyroid***[1][2] - Characterized by **Orphan Annie nuclei**[1], which are large and round with a clear or empty appearance due to the presence of intranuclear cytoplasmic inclusions[1]. - Often associated with **thyroid follicular structures** and is the most common type of thyroid cancer[2]. *Meningioma* - Typically presents with **dural-based tumors** and does not exhibit Orphan Annie nuclei. - Histologically, it may demonstrate **whorled patterns** or calcifications instead. *Carcinoma pituitary* - Involves **adenomatous changes** in the pituitary gland but does not demonstrate the characteristic Orphan Annie nuclei. - More commonly shows **varied cellular morphology** depending on the type of secretory cells (e.g., prolactin, ACTH). *Paraganglioma* - Derived from **neuroendocrine cells**, and presents with **zellballen pattern** rather than Orphan Annie nuclei. - Often shows **chromaffin cells** and is typically associated with catecholamine secretion. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, p. 1099. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 429-430.
Question 642: Which of the following is the most likely proliferating breast mass?
- A. Duct ectasia
- B. Adenosis
- C. Papilloma
- D. Fibroadenoma (Correct Answer)
Explanation: **Fibroadenoma** - A **fibroadenoma** is a benign **biphasic breast tumor** composed of both glandular and stromal tissue, making it a common proliferating mass [3]. - It is often seen in **young women** and typically presents as a firm, movable, non-tender lump [3]. *Duct ectasia* - **Duct ectasia** is a non-proliferative condition characterized by dilation of the **subareolar ducts**, often with inflammation and fibrosis. - It is more commonly associated with **nipple discharge** and **periductal inflammation** rather than being a primary proliferating mass. *Adenosis* - **Adenosis** refers to an increase in the number of **glands or lobules** within the breast parenchyma, which can be sclerosing or florid [2]. - While it involves increased glandular elements, it is generally considered a **benign proliferative change** and less likely to form a distinct, palpable mass compared to a fibroadenoma [1], [4]. *Papilloma* - A **papilloma** is a benign epithelial proliferation within a **duct**, characterized by a central fibrovascular core [2]. - It commonly presents with **nipple discharge**, often bloody, and is typically a smaller lesion within the ductal system rather than a large, palpable proliferating mass [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Breast, pp. 1052-1054. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 446-447. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 448-449. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Breast, p. 1052.