NEET-PG 2013 Practice Questions

Q: What is the longest part of the optic nerve?

Intraorbital. ***Intraorbital*** - The **intraorbital segment** is the **longest portion** of the optic nerve, measuring approximately **25-30 mm**. - It extends from the posterior pole of the eyeball to the **optic canal** and is characterized by a curved, **S-shaped course** within the orbit. - This excess length (approximately 8 mm more than the distance it spans) allows for **free eye movements** without putting tension on the nerve. *Intracranial* - The **intracranial portion** extends from the **optic canal** to the **optic chiasm**, measuring approximately **10-16 mm**. - While often mistakenly thought to be the longest, it is actually the **second longest segment**. - This segment is crucial for the formation of the **optic chiasm** where partial decussation of fibers occurs. *Intracanalicular* - The **intracanalicular portion** passes through the **optic canal** within the sphenoid bone, measuring approximately **4-10 mm**. - This segment is relatively short and constricted, making it vulnerable to compression in conditions like optic nerve gliomas or meningiomas. *Intraocular* - The **intraocular portion** (optic disc) is the **shortest segment**, measuring only about **1 mm**. - It passes through the **lamina cribrosa** of the sclera and is visible on fundoscopy as the optic disc.

Q: Which of the following nerves is commonly damaged during McBurney's incision?

Iliohypogastric nerve. ***Iliohypogastric nerve*** - The **iliohypogastric nerve** is most commonly injured during **McBurney's incision** due to its superficial position and transverse course at the level of the incision. - Damage can lead to **numbness** or altered sensation in the suprapubic region, and sometimes **weakness of the lower abdominal wall**. *Subcostal nerve* - The **subcostal nerve** (T12) runs inferior to the 12th rib and is generally superior to the typical site of a McBurney's incision. - Injury to this nerve is less common during this procedure compared to the iliohypogastric and ilioinguinal nerves. *10th thoracic nerve* - The **10th thoracic nerve** (T10) provides sensation around the umbilicus. - While it contributes to innervation of the abdominal wall, its location is typically well above the area of a standard McBurney's incision, making injury unlikely. *11th thoracic nerve* - The **11th thoracic nerve** (T11) innervates the abdominal wall and is located superior to the typical incision site for appendectomy. - Injury to T11 during a McBurney's incision is uncommon as the nerve's course lies cephalad to the surgical field.

Q: What is the investigation of choice for nasopharyngeal angiofibroma?

Contrast-enhanced CT. ***Contrast-enhanced CT*** - A **contrast-enhanced CT** scan is the investigation of choice for **nasopharyngeal angiofibroma** due to its ability to clearly delineate the extent of the tumor, its vascularity, and its bony involvement. - The contrast highlights the **highly vascular nature** of the angiofibroma, which is crucial for surgical planning and embolization. *X-ray* - **X-rays** provide limited detail of soft tissue structures and mass lesions in the complex anatomy of the nasopharynx. - They are generally not sensitive enough to characterize a tumor like **angiofibroma** or determine its exact extent. *Plain CT* - A **plain CT** (non-contrast CT) can show soft tissue masses and bony erosion but lacks the ability to assess the **vascularity** of the tumor. - Without contrast, it's difficult to differentiate the tumor from surrounding tissues or identify its blood supply, which is critical for **angiofibroma** management. *MRI* - While **MRI** offers excellent soft tissue contrast and is valuable for assessing intracranial extension or perineural spread, **contrast-enhanced CT** is generally preferred as the primary imaging modality for angiofibroma. - **CT with contrast** is superior for demonstrating **bony erosion** and the characteristic **vascularity** of this tumor.

Q: Through which meatus is a nasal puncture typically performed?

Inferior meatus. ---Inferior meatus--- - A nasal puncture for **maxillary sinus irrigation** is typically performed through the **inferior meatus** because it provides direct access to the floor of the nasal cavity and the passage to the maxillary sinus. - The floor of the **inferior meatus** is the thinnest part of the lateral nasal wall, making it an ideal entry point for procedures into the maxillary sinus. *Superior meatus* - The **superior meatus** is associated with the drainage of the **posterior ethmoid cells** and the **sphenoid sinus**. - Puncturing here would not provide access for maxillary sinus irrigation and could risk damage to the **cribriform plate**. *Middle meatus* - The **middle meatus** is where the **maxillary**, **frontal**, and **anterior ethmoid sinuses** primarily drain. - While related to the maxillary sinus, it is not the preferred site for a puncture for irrigation, as it is more complex and less direct than the inferior meatus. *Sphenoethmoidal recess* - The **sphenoethmoidal recess** is located superior to the superior concha and is the drainage site for the **sphenoid sinus**. - This area is too high and posterior to be relevant for a puncture aimed at the **maxillary sinus**.

Q: Adrenal reserve is best tested by means of infusion with

ACTH. ACTH - The **ACTH stimulation test**, also known as the **cosyntropin test**, is the most common dynamic test for assessing adrenal reserve. - Exogenous ACTH (cosyntropin) stimulates the adrenal glands to produce cortisol; a subnormal response indicates adrenal insufficiency. *Corticosteroids* - **Corticosteroids** are hormones (like cortisol) produced by the adrenal glands, or synthetic versions used as medications; they do not test adrenal reserve but rather *replace* adrenal function. - Administering corticosteroids would interfere with, rather than assess, the adrenal gland's ability to produce its own hormones. *LHRH* - **Luteinizing hormone-releasing hormone (LHRH)** is used to assess the function of the anterior pituitary gland and gonads, not the adrenal glands. - An LHRH stimulation test evaluates the pituitary's ability to release LH and FSH, which in turn stimulate gonadal hormone production. *Metyrapone* - The **metyrapone test** assesses the integrity of the **hypothalamic-pituitary-adrenal axis** by blocking cortisol synthesis, which should lead to an increase in ACTH and 11-deoxycortisol [1]. - While it evaluates a part of adrenal function, it is primarily used to differentiate between primary and secondary adrenal insufficiency, and not a direct measure of cortisol production capacity in response to stimulation.

Q: Foldable lens is made up of?

Silicone. ***Silicone*** - **Silicone** was one of the **first materials** used for foldable intraocular lenses (IOLs) and remains widely used today. - Its excellent **elastomeric properties** allow the lens to be folded or rolled for insertion through a **small incision** (typically 2.8-3.2 mm) in modern cataract surgery. - Silicone IOLs are **hydrophobic** and have high biocompatibility with minimal inflammatory response. - **Clinical advantage**: Silicone's flexibility enables **sutureless small-incision cataract surgery**, reducing astigmatism and recovery time. *PMMA* - **PMMA (Polymethyl methacrylate)** is a **rigid material** and was the standard for IOLs before the development of foldable lenses. - Its rigidity requires a **large incision** (5.5-7 mm) for insertion, resulting in more induced astigmatism and longer recovery. - PMMA is not foldable and therefore is not used in modern small-incision cataract surgery. *Hydrogel* - **Hydrophilic acrylic (hydrogel)** is actually another material used for foldable IOLs, along with hydrophobic acrylic. - However, in the context of this question, **silicone** is the most recognized answer as it was the **first foldable material** introduced. - Hydrogel IOLs can absorb water and require different handling during insertion. *None of the options* - This is incorrect as **silicone** is definitively a material used for foldable IOLs.

Q: In an extension type of supracondylar fracture, what is the usual direction of displacement?

Posterolateral. ***Posterolateral*** - In an **extension type supracondylar fracture**, the distal fragment (forearm and hand) is typically displaced **posteriorly and laterally**. - This common displacement pattern is often caused by a **fall on an outstretched hand** with the elbow in extension, forcing the olecranon against the humerus. *Anteromedial* - This is an **uncommon displacement** in supracondylar fractures and is not characteristic of the extension type. - While displacement can have a medial or lateral component, the primary displacement in extension type is posterior. *Anterolateral* - Displacement in an anterior direction is typically seen in **flexion-type supracondylar fractures**, which are much rarer. - Even in flexion-type fractures, the lateral component of displacement is less common than medial. *Posteromedial* - While posterior displacement is characteristic of extension supracondylar fractures, a **posteromedial displacement** is encountered, but **posterolateral** is the *most common* pattern. - The varus force often involved in these injuries tends to promote lateral displacement of the distal fragment.

Q: Which drug is used to keep the patent ductus arteriosus (PDA) open?

PGE1. ***PGE1*** - **Prostaglandin E1** (**PGE1**, alprostadil) is used to maintain the patency of the **ductus arteriosus** in neonates with certain congenital heart defects [1], [2]. - It acts as a **vasodilator** on the smooth muscle of the ductus, preventing its closure and allowing for adequate blood flow prior to surgical correction [1], [2]. *PGI2* - **Prostaglandin I2** (**PGI2**, prostacyclin) is a potent **vasodilator** and **platelet aggregation inhibitor** [1]. - While it has cardiovascular effects, it is primarily used for conditions like **pulmonary hypertension** and not for maintaining ductal patency [1]. *PGF2̑* - **Prostaglandin F2̑** (**PGF2̑**) is involved in processes such as **uterine contractions** and **bronchoconstriction** [1], [2]. - It does not play a role in maintaining the patency of the ductus arteriosus. *PGH2* - **Prostaglandin H2** (**PGH2**) is an immediate precursor in the synthesis of various other prostaglandins and thromboxanes. - It is not directly administered as a drug to maintain ductal patency but is an intermediate in their synthesis.

Q: Primary treatment for localized malignant melanoma is

Wide excision. ***Wide excision*** - This is the **primary treatment** for localized malignant melanoma, aiming to completely remove the tumor along with a surrounding margin of healthy tissue to reduce recurrence risk. - The excisional margin width depends on the **Breslow depth** (tumor thickness). *Radiotherapy* - Not the primary treatment for localized melanoma, as melanoma cells are often **radioresistant**. - It may be used as **adjuvant therapy** for local control in cases of positive margins or nodal involvement, or for palliative care in metastatic disease. *Excision* - While excision is part of the treatment, the term **"wide excision"** specifically implies removing a sufficient margin of healthy tissue around the tumor. - Simple excision without appropriate margins is generally inadequate for malignant melanoma and carries a **high risk of local recurrence**. *Chemotherapy* - It is generally **not the first-line treatment** for localized melanoma due to limited efficacy and significant side effects. - Chemotherapy agents are typically reserved for **advanced or metastatic melanoma** and are often replaced by targeted therapies or immunotherapy in modern practice.

Q: Surgery in varicose veins is NOT attempted in the presence of which of the following?

Deep vein thrombosis. ***Deep vein thrombosis*** - **Surgery in varicose veins is absolutely contraindicated in the presence of DVT** (both acute and chronic) - In **acute DVT**, the deep venous system is already compromised, and removing superficial veins could further impair venous return and worsen the thrombotic state - In **chronic DVT with post-thrombotic syndrome**, the deep veins may be occluded or heavily damaged, and the superficial varicosities often serve as **crucial collateral vessels** to maintain venous drainage—their removal would be detrimental - Surgery should only be considered after complete resolution of acute DVT and adequate anticoagulation *Multiple incompetent perforators* - **NOT a contraindication**—incompetent perforators are actually a common indication for surgical treatment - Incompetent perforators contribute to venous insufficiency and recurrent varicose veins - Can be addressed surgically with **subfascial endoscopic perforator surgery (SEPS)** or endovenous ablation techniques - Their presence often indicates need for more comprehensive treatment alongside superficial venous surgery *Varicose veins with leg ulcer* - **NOT a contraindication**—venous leg ulcers are actually an **indication for varicose vein surgery** - Leg ulcers result from chronic venous hypertension due to venous insufficiency - Surgical treatment (saphenous vein ablation, ligation and stripping, or sclerotherapy) reduces venous hypertension and improves venous drainage - Surgery promotes ulcer healing and prevents recurrence when combined with appropriate wound care *None of the above* - Incorrect because **Deep Vein Thrombosis (DVT) is a well-established contraindication** to varicose vein surgery

Question 1

What is the longest part of the optic nerve?

Accepted Answer

Intraorbital

Answer

Intracanalicular

Answer

Intraocular

Answer

Intracranial

Question 2

Which of the following nerves is commonly damaged during McBurney's incision?

Accepted Answer

Iliohypogastric nerve

Answer

Subcostal nerve

Answer

11th thoracic nerve

Answer

10th thoracic nerve

Question 3

What is the investigation of choice for nasopharyngeal angiofibroma?

Accepted Answer

Contrast-enhanced CT

Answer

Plain CT

Answer

X-ray

Answer

MRI

Question 4

Through which meatus is a nasal puncture typically performed?

Accepted Answer

Inferior meatus

Answer

Superior meatus

Answer

Middle meatus

Answer

Sphenoethmoidal recess

Question 5

Adrenal reserve is best tested by means of infusion with

Accepted Answer

ACTH

Answer

Metyrapone

Answer

Corticosteroids

Answer

LHRH

Question 6

Foldable lens is made up of?

Accepted Answer

Silicone

Answer

PMMA

Answer

Hydrogel

Answer

None of the options

Question 7

In an extension type of supracondylar fracture, what is the usual direction of displacement?

Accepted Answer

Posterolateral

Answer

Anteromedial

Answer

Anterolateral

Answer

Posteromedial

Question 8

Which drug is used to keep the patent ductus arteriosus (PDA) open?

Accepted Answer

PGE1

Answer

PGI2

Answer

PGH2

Answer

PGF2α

Question 9

Primary treatment for localized malignant melanoma is

Accepted Answer

Wide excision

Answer

Radiotherapy

Answer

Excision

Answer

Chemotherapy

Question 10

Surgery in varicose veins is NOT attempted in the presence of which of the following?

Accepted Answer

Deep vein thrombosis

Answer

Multiple incompetent perforators

Answer

Varicose veins with leg ulcer

Answer

None of the above

NEET-PG 2013

Anatomy

ENT

Internal Medicine

Ophthalmology

Orthopaedics

Pharmacology

Surgery