Anatomy
1 questionsWhich nerve is not involved in superior orbital fissure syndrome?
NEET-PG 2013 - Anatomy NEET-PG Practice Questions and MCQs
Question 971: Which nerve is not involved in superior orbital fissure syndrome?
- A. 1st cranial nerve (Correct Answer)
- B. 3rd cranial nerve
- C. 4th cranial nerve
- D. 6th cranial nerve
Explanation: ***1st cranial nerve*** - The **olfactory nerve (CN I)** is responsible for the sense of smell [2] and passes through the **cribriform plate** of the ethmoid bone, not the superior orbital fissure. - Due to its distinct pathway, it is not affected in **superior orbital fissure syndrome**. *3rd cranial nerve* - The **oculomotor nerve (CN III)** passes through the superior orbital fissure and is frequently involved in the syndrome. - Its involvement leads to ophthalmoplegia, ptosis, and a dilated pupil due to paralysis of most extrinsic ocular muscles [1], [3] and the parasympathetic fibers [1]. *4th cranial nerve* - The **trochlear nerve (CN IV)** also travels through the superior orbital fissure. - Damage to this nerve causes **diplopia** and impaired downward and intorsion movements of the eye due to paralysis of the **superior oblique muscle** [3]. *6th cranial nerve* - The **abducens nerve (CN VI)** enters the orbit via the superior orbital fissure. - Injury to the abducens nerve results in **lateral rectus muscle** palsy, leading to esotropia (medial deviation of the eye) and impaired abduction [3].
Internal Medicine
4 questionsWhat condition is associated with copper deposition in the cornea?
What is Reifenstein syndrome?
Which of the following is not an absolute indication for hemodialysis?
Which of the following is NOT a feature of scleroderma?
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 971: What condition is associated with copper deposition in the cornea?
- A. Keratoglobus
- B. Keratoconus
- C. Siderosis
- D. Wilson's disease (Correct Answer)
Explanation: ***Wilson's disease*** - Wilson's disease is a genetic disorder of **copper metabolism** leading to excess copper accumulation in various tissues, including the cornea [1]. - This copper deposition in the posterior Descemet's membrane of the cornea forms a distinctive golden-brown or greenish-brown ring known as the **Kayser-Fleischer ring**. *Keratoconus* - This condition is characterized by progressive thinning and steepening of the cornea, causing it to bulge into a **cone-like shape**. - It primarily affects vision due to irregular astigmatism and does not involve copper deposition. *Keratoglobus* - Keratoglobus is a rare corneal ectatic disorder where the entire cornea is thinned and bulges forward, giving it a **globe-like appearance**. - It is congenital and typically runs in families, and it is not associated with copper deposition. *Siderosis* - Siderosis refers to the deposition of **iron** in various tissues, often due to chronic hemorrhage or metallic foreign bodies. - In the eye, it can occur after intraocular iron foreign bodies, leading to retinal degeneration and other ocular complications, but it does not involve copper.
Question 972: What is Reifenstein syndrome?
- A. Partial androgen insensitivity syndrome due to receptor mutation. (Correct Answer)
- B. Complete androgen insensitivity syndrome with female external genitalia
- C. 5-alpha reductase deficiency causing ambiguous genitalia
- D. Gonadal dysgenesis with streak gonads
Explanation: Partial androgen insensitivity syndrome due to receptor mutation. - **Reifenstein syndrome** is a form of **partial androgen insensitivity syndrome (PAIS)**, characterized by varying degrees of undervirilization in 46,XY individuals. [4] - It results from mutations in the **androgen receptor (AR) gene**, leading to impaired androgen signaling. [4] *Complete androgen insensitivity syndrome with female external genitalia* - This describes **complete androgen insensitivity syndrome (CAIS)**, where affected individuals are 46,XY with completely female external genitalia, normal breast development, but no uterus. [4] - Unlike Reifenstein syndrome, there are no signs of virilization. [4] *5-alpha reductase deficiency causing ambiguous genitalia* - **5-alpha reductase deficiency** impedes the conversion of testosterone to the more potent **dihydrotestosterone (DHT)**, which is crucial for external male genital development. - While it causes **ambiguous genitalia**, it's a defect in hormone metabolism, not the androgen receptor itself. *Gonadal dysgenesis with streak gonads* - **Gonadal dysgenesis** refers to conditions where the gonads (testes or ovaries) fail to develop or develop abnormally, often leading to **streak gonads**. [3] - This is a primary gonadal developmental defect, distinct from disorders of androgen action or synthesis. [1], [2]
Question 973: Which of the following is not an absolute indication for hemodialysis?
- A. GI bleeding (Correct Answer)
- B. Convulsions
- C. Pericarditis
- D. Hyperkalemia of 6.5 mEq/L
Explanation: ***GI bleeding*** - While patients on dialysis may experience gastrointestinal bleeding, it is not a direct indication for initiating or continuing **hemodialysis**. - **GI bleeding** in end-stage renal disease (ESRD) patients can be due to various causes and requires specific management of the bleeding itself, not necessarily an alteration in dialysis prescription. *Convulsions* - **Convulsions** in patients with renal failure, especially due to uremia, are a severe manifestation of **uremic encephalopathy**. - This is an absolute indication for **hemodialysis** as it rapidly removes uremic toxins causing central nervous system dysfunction. *Pericarditis* - **Uremic pericarditis**, characterized by inflammation of the pericardium due to accumulation of uremic toxins, is a serious complication of renal failure. - It is an absolute indication for **hemodialysis** to prevent further cardiac complications like cardiac tamponade. *Hyperkalemia of 6.5 mEq/L* - Severe **hyperkalemia** (typically > 6.0-6.5 mEq/L) is a life-threatening electrolyte imbalance that can cause cardiac arrhythmias. - **Hemodialysis** is highly effective in rapidly removing potassium from the body and is an absolute indication, especially if unresponsive to other medical therapies.
Question 974: Which of the following is NOT a feature of scleroderma?
- A. Restrictive cardiomyopathy
- B. Halitosis
- C. Syndactyly (Correct Answer)
- D. Decrease in tone of LES
Explanation: ***Syndactyly*** - **Syndactyly** (fusion of digits) is a congenital anomaly and is **not** a typical feature of scleroderma. - Scleroderma primarily involves **fibrosis** and vascular changes, leading to skin thickening, not digit fusion [1]. *Decrease in tone of LES* - A **decrease in tone of the lower esophageal sphincter (LES)** is a common gastrointestinal manifestation of scleroderma. - This leads to **gastroesophageal reflux disease (GERD)** and related symptoms due to smooth muscle atrophy and fibrosis. *Restrictive cardiomyopathy* - **Restrictive cardiomyopathy** can occur in scleroderma due to **myocardial fibrosis**, leading to impaired diastolic filling. - This is a serious cardiac complication that can cause **heart failure**. *Halitosis* - **Halitosis** (bad breath) can be an indirect manifestation of scleroderma, often associated with severe **GERD**. - Impaired esophageal motility and reflux are common in scleroderma and can contribute to dental problems and **oral dysbiosis**, which can cause halitosis.
Ophthalmology
5 questionsCommotio retinae affects which part of the retina -
Parachute lesions are associated with which of the following conditions?
Which of the following is a specific sign of albinism?
Epithelial xerosis of conjunctiva is caused by?
Which agent is known to cause corneal ulcers that may resemble fungal infections?
NEET-PG 2013 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 971: Commotio retinae affects which part of the retina -
- A. Posterior pole (Correct Answer)
- B. Peripheral retina
- C. Inferior-nasal part
- D. Superior-nasal part
Explanation: ***Posterior pole*** - **Commotio retinae**, also known as Berlin's edema, primarily affects the **posterior pole** of the retina, particularly the macula. - This condition results from **blunt trauma** to the globe, causing disruption of the outer retinal photoreceptors and retinal pigment epithelium, leading to retinal whitening in the area of impact. *Peripheral retina* - While blunt trauma can affect the peripheral retina, commotio retinae specifically refers to the **edematous whitening** that occurs more centrally. - Trauma to the periphery is more commonly associated with **retinal tears or detachments**, rather than the diffuse whitening seen in commotio retinae. *Inferior-nasal part* - This is a specific quadrant of the retina, but commotio retinae is not confined to or preferentially found in the **inferior-nasal part**. - The location of commotio retinae depends on the **point of impact** and the transmission of force, but symptoms are most prominent when the macula at the posterior pole is involved. *Superior-nasal part* - Similar to the inferior-nasal part, the **superior-nasal part** is a specific retinal quadrant. - Commotio retinae is a more generalized finding of retinal edema and whitening due to trauma, not consistently localized to this particular region, though it can occur if that area is directly impacted.
Question 972: Parachute lesions are associated with which of the following conditions?
- A. Eale's disease (Correct Answer)
- B. Diabetes
- C. Sickle cell anemia
- D. None of the options
Explanation: ***Eale's disease*** - **Eale's disease** is an idiopathic retinal perivasculitis affecting young males, characterized by recurrent vitreous hemorrhages. - In the context of this question (NEET-2013), the term "parachute lesions" refers to the characteristic pattern of hemorrhages seen in Eale's disease. - The disease features retinal periphlebitis, capillary non-perfusion, and neovascularization leading to vitreous hemorrhage. - **Note:** The term "parachute hemorrhages" in broader ophthalmology typically describes preretinal/subhyaloid hemorrhages that settle inferiorly (boat-shaped), more commonly seen in proliferative diabetic retinopathy. *Diabetes* - **Diabetic retinopathy** presents with microaneurysms, dot-blot hemorrhages, hard exudates, cotton-wool spots, and neovascularization. - While proliferative diabetic retinopathy can cause preretinal "parachute-shaped" hemorrhages (boat-shaped hemorrhages that settle inferiorly), this is not the association being tested in this NEET-2013 question. - The specific context of this exam question associates the term with Eale's disease. *Sickle cell anemia* - **Sickle cell retinopathy** features characteristic sea-fan neovascularization in the peripheral retina. - Can cause salmon-patch hemorrhages, black sunburst lesions, and angioid streaks. - While vitreous hemorrhage can occur, "parachute lesions" is not standard terminology for sickle cell retinopathy manifestations. *None of the options* - This option is incorrect because **Eale's disease** is the correct answer according to the NEET-2013 exam key.
Question 973: Which of the following is a specific sign of albinism?
- A. Iris transillumination (Correct Answer)
- B. Sensitivity to light (photophobia)
- C. Involuntary eye movements (nystagmus)
- D. Decreased visual acuity
Explanation: ***Iris transillumination*** - This is a highly **specific sign** of albinism, resulting from the severe reduction or absence of pigment in the iris. - When light shines through the pupil, it passes through the unpigmented iris, creating a visible red reflex, indicating the lack of pigment that normally blocks the light. *Sensitivity to light (photophobia)* - While common in albinism due to the lack of pigment in the iris and retina allowing more light to enter the eye, **photophobia is not specific** to albinism. - It can be a symptom of various other ocular conditions like uveitis, corneal abrasions, or migraines. *Involuntary eye movements (nystagmus)* - **Nystagmus is frequently associated with albinism** due to foveal hypoplasia and impaired visual development but is **not specific**. - It can also be caused by neurological disorders, inner ear problems, or other ocular conditions. *Decreased visual acuity* - **Reduced vision is a characteristic feature of albinism** resulting from foveal hypoplasia and abnormal optic nerve pathways, but it is **not specific** to the condition. - Numerous eye conditions, such as refractive errors, cataracts, and retinal diseases, can lead to decreased visual acuity.
Question 974: Epithelial xerosis of conjunctiva is caused by?
- A. Xerophthalmia (Correct Answer)
- B. Infectious conjunctivitis caused by Chlamydia trachomatis
- C. Autoimmune blistering conjunctivitis
- D. Bacterial conjunctivitis due to Corynebacterium diphtheriae
Explanation: ***Xerophthalmia*** - **Xerophthalmia** is a medical condition characterized by **dryness of the eye**, often due to **vitamin A deficiency**. - **Epithelial xerosis of the conjunctiva** is one of the early and hallmark signs of xerophthalmia, representing the drying and thickening of the conjunctival epithelium due to goblet cell loss and squamous metaplasia. *Infectious conjunctivitis caused by Chlamydia trachomatis* - This typically causes **trachoma**, characterized by chronic inflammation, scarring, and eventual blindness. - While it can lead to dryness and scarring in later stages due to **symblepharon** or **entropion**, it does not primarily manifest as epithelial xerosis. *Autoimmune blistering conjunctivitis* - This condition involves **immune-mediated inflammation** leading to subepithelial blistering, scarring, and shrinkage of the conjunctiva. - It results in significant **ocular surface damage** and vision loss but is distinct from the primary epithelial changes seen in xerosis due to vitamin A deficiency. *Bacterial conjunctivitis due to Corynebacterium diphtheriae* - **Diphtheritic conjunctivitis** is a severe form of bacterial conjunctivitis that causes a distinctive **"pseudomembrane"** on the conjunctiva. - It leads to acute inflammation and potentially systemic illness, not primarily epithelial xerosis.
Question 975: Which agent is known to cause corneal ulcers that may resemble fungal infections?
- A. Nocardia asteroides (Correct Answer)
- B. Mycobacterium
- C. Klebsiella pneumoniae
- D. Chlamydia trachomatis
Explanation: ***Nocardia asteroides*** - This organism can cause **Nocardia keratitis**, which often presents with a **feathery or crystalline appearance** in the cornea, mimicking a fungal infection. - It tends to occur in patients with **contact lens use** or ocular trauma and requires specific antimicrobial treatment different from fungal therapy. *Mycobacterium* - **Atypical mycobacteria** can cause chronic, indolent corneal ulcers, particularly after trauma or surgery. - While they can be challenging to diagnose, their appearance typically differs from the **feathery morphology** associated with fungal or Nocardia infections. *Klebsiella pneumoniae* - **Klebsiella pneumoniae** is a common cause of **bacterial keratitis**, especially in contact lens wearers. - Infections usually manifest as a rapidly progressing infiltrate with significant inflammation and often produce abundant **mucopurulent discharge**, not typically mistaken for fungal infections. *Chlamydia trachomatis* - **Chlamydia trachomatis** is the causative agent of **trachoma**, leading to recurrent conjunctivitis and eventually corneal scarring and blindness in endemic areas. - It does not cause acute corneal ulcers that resemble fungal infections; rather, it results in a chronic inflammatory process with **follicular conjunctivitis** and **pannus formation**.