Anesthesiology
1 questionsAll of the following drugs increase the risk of postoperative nausea and vomiting after squint surgery in children except?
NEET-PG 2015 - Anesthesiology NEET-PG Practice Questions and MCQs
Question 861: All of the following drugs increase the risk of postoperative nausea and vomiting after squint surgery in children except?
- A. Halothane
- B. Propofol (Correct Answer)
- C. Nitrous Oxide
- D. Opioids
Explanation: ***Propofol*** - Propofol is known to have **antiemetic properties** and is often used to reduce the incidence of postoperative nausea and vomiting (PONV). - Its mechanism involves modulating **GABA-A receptors** and potentially other pathways that suppress emetic responses. *Halothane* - **Inhalational anesthetics** like halothane are a significant risk factor for PONV, particularly in children and following surgeries like squint repair. - They tend to increase PONV by directly stimulating the **chemoreceptor trigger zone** and altering gut motility. *Opioids* - Opioids, commonly used for postoperative pain control, are a well-known cause of **nausea and vomiting**. - They activate **opioid receptors** in the chemoreceptor trigger zone and the gastrointestinal tract, leading to emesis and delayed gastric emptying. *Nitrous Oxide* - The use of **nitrous oxide** as part of a general anesthetic regimen has been consistently associated with an increased risk of PONV. - It is believed to contribute to PONV by increasing the risk of **bowel distension** and stimulating neurotransmitter release involved in emesis.
Internal Medicine
1 questionsMacular sparing is associated with lesions in:
NEET-PG 2015 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 861: Macular sparing is associated with lesions in:
- A. Lesions in the optic nerve
- B. Lesions in the lateral geniculate body
- C. Lesions in the occipital cortex (Correct Answer)
- D. Lesions in the optic chiasma
Explanation: ***Lesions in the occipital cortex*** - **Macular sparing** occurs when the central visual field (macula) is preserved despite damage to the occipital cortex, often due to its dual blood supply from the **middle cerebral artery** and the **posterior cerebral artery**. [2] - This phenomenon typically results from a **vascular lesion** in the occipital lobe, leading to a **homonymous hemianopia** with a distinct sparing of the foveal region. [2], [3] *Lesions in the optic nerve* - Lesions in the optic nerve cause **monocular vision loss** or central scotomas, rather than the homonymous visual field defects associated with macular sparing. [2] - Damage here affects the visual pathway **before** the optic chiasm, impacting the entire visual input from one eye. [2] *Lesions in the lateral geniculate body* - Lesions in the **lateral geniculate body (LGB)** produce **contralateral homonymous hemianopia** or quadrantanopia, but typically **do not exhibit macular sparing** as consistently as cortical lesions. - The LGB processes visual information from both eyes before relaying it to the visual cortex. [1] *Lesions in the optic chiasma* - Lesions in the **optic chiasma** classically cause **bitemporal hemianopia**, affecting the temporal visual fields of both eyes. [2] - This type of visual field defect is distinct from the homonymous defects seen with macular sparing, as it results from damage to the **crossing nasal fibers**. [2]
Ophthalmology
6 questionsDalrymple's sign of ocular Graves' disease refers to which of the following?
D Shaped pupil is seen in which condition?
In which of the following conditions does Berlin's edema occur?
All of the following are complications of traumatic hyphema except which of the following?
What is the most common eye lesion in HIV?
Which optical instrument utilizes the principle of total internal reflection?
NEET-PG 2015 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 861: Dalrymple's sign of ocular Graves' disease refers to which of the following?
- A. Retraction of the upper lid (Correct Answer)
- B. Lid lag
- C. Proptosis
- D. Convergence insufficiency
Explanation: ***Retraction of the upper lid*** - **Dalrymple's sign** specifically refers to the **wide-eyed stare** seen in **Graves' ophthalmopathy** due to **retraction of the upper eyelid**. - This symptom is caused by sympathetic overactivity of the **levator palpebrae superioris muscle**. *Lid lag* - **Lid lag (Graefe's sign)** is a different ocular sign where the **upper eyelid lags behind the globe** on downward gaze. - While also seen in **Graves' disease**, it is distinct from constant upper lid retraction. *Proptosis* - **Proptosis**, or **exophthalmos**, is the **forward protrusion of the eyeball** from the orbit. - This is a common feature of **Graves' ophthalmopathy**, but it is not what Dalrymple's sign refers to. *Convergence insufficiency* - **Convergence insufficiency (Moebius sign)** refers to the **inability to maintain convergence** during near vision. - While this can occur in **thyroid eye disease**, it is not Dalrymple's sign.
Question 862: D Shaped pupil is seen in which condition?
- A. Anterior synechiae
- B. Anterior Uveitis
- C. Iridodialysis (Correct Answer)
- D. Iridodonesis
Explanation: ***Iridodialysis*** - **Iridodialysis** is a disinsertion or separation of the iris from its root at the ciliary body. - This separation creates a D-shaped or keyhole pupil, as the detached portion of the iris no longer contributes to the circular pupillary margin. *Anterior Uveitis* - **Anterior uveitis** is inflammation of the iris and ciliary body, primarily causing miosis (constricted pupil), not a D-shaped pupil. - It can lead to posterior synechiae, resulting in an irregular, but not typically D-shaped, pupil. *Anterior synechiae* - **Anterior synechiae** involve adhesions between the iris and the corneal endothelium or trabecular meshwork. - While they can cause an irregular pupil shape, they typically pull the iris towards the cornea rather than creating a D-shape from iris root disinsertion. *Iridodonesis* - **Iridodonesis** refers to tremors or wobbling of the iris, often seen in cases of aphakia or subluxated lenses, due to lack of support. - It describes a movement disorder of the iris rather than an abnormal, fixed pupil shape like a D-shaped pupil.
Question 863: In which of the following conditions does Berlin's edema occur?
- A. Open angle glaucoma
- B. After cataract surgery
- C. After concussional trauma (Correct Answer)
- D. Diabetic retinopathy
Explanation: ***After concussional trauma*** - **Berlin's edema**, also known as **commotio retinae**, is a form of **retinal edema** that occurs following **blunt trauma** to the eye. - It results from the disruption of the **photoreceptor outer segments** and retinal pigment epithelium, leading to a **dull, gray-white appearance** of the retina. *Open angle glaucoma* - Characterized by **progressive optic nerve damage** and visual field loss, typically due to elevated intraocular pressure, without retinal edema. - The primary pathology involves the **trabecular meshwork**, not direct retinal swelling. *After cataract surgery* - A common complication is **cystoid macular edema** (Irvine-Gass syndrome), which affects the macula and can cause blurred vision. - This is distinct from Berlin's edema, as it is a **post-surgical inflammatory response**, not a direct traumatic injury. *Diabetic retinopathy* - Involves various retinal changes due to diabetes, such as **microaneurysms**, hemorrhages, and **macular edema** from leaky vessels. - It is a **metabolic and vascular disease**, not a direct consequence of acute ocular trauma.
Question 864: All of the following are complications of traumatic hyphema except which of the following?
- A. Pupillary Block
- B. Posterior synechiae
- C. Rebleeding
- D. Corneal Ulcer (Correct Answer)
Explanation: ***Corneal Ulcer*** - A **corneal ulcer** is typically caused by infection, trauma, or exposure keratitis and is not a direct complication of blood in the anterior chamber from a **traumatic hyphema**. - While prolonged elevation of **intraocular pressure** from hyphema could theoretically impair corneal health, a direct ulcer is not a typical or primary complication. *Rebleeding* - **Rebleeding** is a common and serious complication of hyphema, usually occurring 2-7 days after the initial injury. - It often results in a more significant bleed and carries a higher risk of complications such as **elevated intraocular pressure** and **blood staining of the cornea**. *Pupillary Block* - **Pupillary block** can occur if the amount of blood from the hyphema prevents the flow of aqueous humor from the posterior to the anterior chamber. - This blockage leads to a buildup of **aqueous humor** in the posterior chamber, causing the iris to bow forward and potentially precipitating **acute angle-closure glaucoma**. *Posterior synechiae* - **Posterior synechiae** can develop due to inflammation (uveitis) associated with the hyphema, where the iris adheres to the anterior lens capsule. - This complication can lead to **irregular pupil shape**, **pupillary block glaucoma**, or other visual disturbances.
Question 865: What is the most common eye lesion in HIV?
- A. Kaposi Sarcoma of Lid
- B. Cotton wool spots (Correct Answer)
- C. CMV Retinitis
- D. Choroiditis
Explanation: ***Cotton wool spots*** - These are the most common ocular manifestation in HIV-positive individuals, resulting from **ischemic retinal nerve fiber layer damage**. - While not vision-threatening themselves, their presence indicates **microvascular damage** and can be a sign of systemic disease progression. *Kaposi Sarcoma of Lid* - While Kaposi sarcoma can affect the eyelids in HIV patients, it is **not the most common ocular lesion**. - It presents as a **reddish-purple nodule** or plaque and is an indicator of advanced immunosuppression. *CMV Retinitis* - Cytomegalovirus (CMV) retinitis is a significant and **vision-threatening opportunistic infection** in advanced HIV. - However, it occurs in patients with **severe immunosuppression** (low CD4 counts) and is less common overall than cotton wool spots. *Choroiditis* - Choroiditis, an inflammation of the choroid, can occur in HIV patients due to various opportunistic infections or directly from the virus. - It is **less prevalent** than cotton wool spots and typically requires specific etiologies beyond HIV itself.
Question 866: Which optical instrument utilizes the principle of total internal reflection?
- A. Gonioscope (Correct Answer)
- B. Pachymeter
- C. Ophthalmoscope
- D. Lensometer
Explanation: ***Gonioscope*** - A **gonioscope** uses mirrors or prisms to allow visualization of the **anterior chamber angle**, leveraging **total internal reflection** to bypass the normal optical limitations of the cornea. - The principle of total internal reflection occurs when light traveling from a denser medium (like the prism/mirror in the gonioscope) hits an interface with a less dense medium (like air or the aqueous humor) at an angle greater than the **critical angle**, causing all light to reflect back. *Pachymeter* - A **pachymeter** is used to measure the **thickness of the cornea**, typically employing ultrasound or optical methods. - It does not rely on total internal reflection but rather on the time-of-flight of sound waves or the reflection/scattering of light from corneal layers. *Ophthalmoscope* - An **ophthalmoscope** is used to examine the posterior segment of the eye, including the **fundus**, optic disc, and retina. - It works by directing a light source into the eye and viewing the reflected light, using lenses to focus the image, without utilizing total internal reflection. *Lensometer* - A **lensometer** (or focimeter) is an optician's instrument used to measure the prescription of eyeglasses or contact lenses, including **sphere, cylinder, and axis**. - Its operation is based on standard lens optics and does not involve the principle of total internal reflection.
Pathology
1 questionsParasitosis of extraocular eye muscles is seen in?
NEET-PG 2015 - Pathology NEET-PG Practice Questions and MCQs
Question 861: Parasitosis of extraocular eye muscles is seen in?
- A. Trichinella infection (Correct Answer)
- B. Cysticercus infection
- C. Amoebic infection
- D. Ascariasis infection
Explanation: ***Trichinella infection*** - **Trichinellosis** (caused by *Trichinella spiralis*) commonly involves the **extraocular muscles** during the muscle encystment phase [1]. - Ocular symptoms like **periorbital edema**, eosinophilic myositis of extraocular muscles, and subconjunctival hemorrhage are characteristic [1]. *Cysticercus infection* - **Cysticercosis**, caused by *Taenia solium* larvae, can affect the eye, predominantly forming **subretinal** or **vitreous cysts** [2]. - While it can involve orbital muscles, involvement of extraocular muscles is less typical and less specific than in trichinellosis [2]. *Amoebic infection* - **Amoebic infections** primarily cause **keratitis** (e.g., *Acanthamoeba*) [3] or can lead to granulomatous encephalitis in immunocompromised individuals. - They do not typically cause direct parasitosis of the extraocular muscles. *Ascariasis infection* - **Ascariasis**, caused by *Ascaris lumbricoides*, is an intestinal nematode and is not known to infect the extraocular muscles. - Ocular manifestations are rare and usually involve migration of adult worms to the orbit or eyelid, not muscle encystment. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Infectious Diseases, pp. 404-405. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Infectious Diseases, pp. 403-404. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Manifestations Of Central And Peripheral Nervous System Disease, pp. 735-736.
Psychiatry
1 questionsWhich of the following is NOT a feature of CHARGE syndrome?
NEET-PG 2015 - Psychiatry NEET-PG Practice Questions and MCQs
Question 861: Which of the following is NOT a feature of CHARGE syndrome?
- A. Esophageal Atresia (Correct Answer)
- B. Congenital heart disease
- C. Urinary tract defects
- D. Eye Coloboma
- E. Choanal Atresia
Explanation: ***Esophageal Atresia*** - While other **tracheoesophageal abnormalities** can occur in CHARGE syndrome, **esophageal atresia** is not typically considered one of the core diagnostic criteria. - The acronym CHARGE stands for a specific set of features, and esophageal atresia is not directly included, unlike **choanal atresia**. *Eye Coloboma* - **Coloboma** of the eye, particularly the iris or retina, is a **major diagnostic feature** of CHARGE syndrome. - This congenital malformation results from incomplete closure of the **choroid fissure** during development. *Congenital heart disease* - Various types of **congenital heart defects**, such as **tetralogy of Fallot** or an **atresia of the aortic valve**, are common in CHARGE syndrome. - These cardiac anomalies are a **major diagnostic criterion** and significantly impact patient management. *Choanal Atresia* - **Choanal atresia** represents the "A" in the CHARGE acronym and is a **major diagnostic criterion**. - This condition involves blockage of the nasal passages and is one of the most characteristic features of the syndrome. *Urinary tract defects* - **Genital and urinary abnormalities** are frequently observed in individuals with CHARGE syndrome. - These can include **hypoplastic genitalia** and **kidney abnormalities**, classifying as a **minor diagnostic feature**.