Olfactory Disorders — MCQs
A child is brought to the paediatric OPD with fever of 24 hours duration. History reveals 3 episodes of chest infection and passage of foul smelling stools. The most probable diagnosis is-
Which of the following statements about vasomotor rhinitis is false?
Which of the following statements about nasal polyps is the MOST accurate?
Where are mitral cells primarily located?
CSF rhinorrhea is diagnosed by: MP 07
Among the following trigeminal nerve divisions, which one is involved in orbital apex syndrome?
Impulses generated in the taste buds of the tongue reach the cerebral cortex via the
Investigations used for CSF rhinorrhea are all except:
What test is not used for testing olfaction?
In which condition is Young's operation performed?
Olfactory Disorders Indian Medical PG Practice Questions and MCQs
Question 1: A child is brought to the paediatric OPD with fever of 24 hours duration. History reveals 3 episodes of chest infection and passage of foul smelling stools. The most probable diagnosis is-
- A. Crigler-Najjar Syndrome
- B. Maple Syrup urine Disease
- C. Bilirubin Conjugation Defect
- D. Cystic Fibrosis (Correct Answer)
Explanation: ***Cystic Fibrosis*** - Recurrent **chest infections** and **foul-smelling stools** (due to pancreatic insufficiency leading to malabsorption) are classic hallmarks of cystic fibrosis. - This genetic disorder primarily affects the **lungs** and **digestive system**, leading to thick, sticky mucus. *Crigler-Najjar Syndrome* - This syndrome is a rare genetic disorder characterized by severe **unconjugated hyperbilirubinemia**, leading to **jaundice** and potential neurological damage. - It does not typically present with recurrent chest infections or foul-smelling stools. *Maple Syrup urine Disease* - This is an **amino acid metabolism disorder** leading to the accumulation of branched-chain amino acids, characterized by a distinctive "maple syrup" odor in the urine. - It presents with neurological symptoms, feeding difficulties, and developmental delay, not primarily chest infections and foul-smelling stools. *Bilirubin Conjugation Defect* - This refers to conditions like Gilbert's syndrome or Crigler-Najjar syndrome, which cause varying degrees of **unconjugated hyperbilirubinemia** and **jaundice**. - It does not explain the recurrent respiratory infections or malabsorption symptoms like foul-smelling stools.
Question 2: Which of the following statements about vasomotor rhinitis is false?
- A. It is an infective condition (Correct Answer)
- B. It primarily presents with nasal congestion and rhinorrhea
- C. It involves autonomic dysfunction of nasal blood vessels
- D. It is triggered by non-allergic stimuli like weather changes and strong odors
Explanation: ***It is an infective condition*** - **Vasomotor rhinitis** is a **non-allergic, non-infectious** condition of the nasal passages. - Its pathophysiology involves **autonomic nervous system dysfunction** affecting nasal blood vessels, not microbial infection. *It primarily presents with nasal congestion and rhinorrhea* - This statement is **true** because classic symptoms of vasomotor rhinitis include persistent or intermittent **nasal congestion** and **rhinorrhea** (runny nose). - These symptoms result from the dysregulation of the autonomic control over nasal vasculature and glands. *It involves autonomic dysfunction of nasal blood vessels* - This statement is **true** and describes the core mechanism of vasomotor rhinitis, where the **parasympathetic nervous system** is relatively overactive, leading to vasodilation and increased glandular secretions. - This dysfunction causes the characteristic symptoms without an allergic or infectious trigger. *It is triggered by non-allergic stimuli like weather changes and strong odors* - This statement is **true** as patients with vasomotor rhinitis often report symptoms triggered by **environmental irritants** such as strong perfumes, temperature changes, humidity fluctuations, or even emotional stress. - These triggers differentiate it clinically from allergic rhinitis.
Question 3: Which of the following statements about nasal polyps is the MOST accurate?
- A. They are usually benign. (Correct Answer)
- B. They are more common in adults than children.
- C. They are commonly associated with aspirin sensitivity.
- D. They are a complication of chronic sinusitis.
Explanation: ***They are usually benign.*** - The vast majority of **nasal polyps** are benign inflammatory lesions, originating from the nasal or sinus mucosa. - They are not considered neoplastic, differentiating them from malignant tumors that can occur in the nasal cavity. *They are more common in adults than children.* - While nasal polyps can occur in children, especially in association with **cystic fibrosis** or primary ciliary dyskinesia, they are still significantly more prevalent in adults. - The peak incidence is typically in individuals between 40 and 60 years old. *They are commonly associated with aspirin sensitivity.* - **Aspirin-exacerbated respiratory disease (AERD)**, also known as Samter's triad, is a specific syndrome characterized by asthma, recurrent nasal polyps, and aspirin sensitivity. - However, not all patients with nasal polyps have aspirin sensitivity; it's a specific subset of patients. *They are a complication of chronic sinusitis.* - While **chronic rhinosinusitis with nasal polyps (CRSwNP)** is a common presentation, and polyps often develop in the context of chronic inflammation, they are not strictly a "complication." - Rather, nasal polyp formation is a manifestation or an end-stage of a specific inflammatory process within chronic rhinosinusitis, not merely an incidental side effect.
Question 4: Where are mitral cells primarily located?
- A. Kidney
- B. Mitral valve
- C. Olfactory bulb (Correct Answer)
- D. Optic nerve
Explanation: Olfactory bulb - **Mitral cells** are the primary projection neurons in the **olfactory bulb**, receiving extensive input from olfactory sensory neurons [1]. - They play a crucial role in processing and transmitting **olfactory information** from the nose to higher brain regions [1]. *Kidney* - The kidney contains various specialized cells for filtration and reabsorption (e.g., **podocytes**, **tubular cells**), but no mitral cells. - Its primary function is maintaining **fluid and electrolyte balance** and waste excretion, unrelated to olfaction. *Mitral valve* - The **mitral valve** is located in the heart, separating the left atrium and left ventricle. - It consists of connective tissue and endothelial cells and is essential for regulating **blood flow**, not scent perception. *Optic nerve* - The **optic nerve** transmits visual information from the retina to the brain and is composed of retinal ganglion cell axons [2]. - Its function is entirely distinct from olfaction, involving **light perception** and visual processing [2].
Question 5: CSF rhinorrhea is diagnosed by: MP 07
- A. Halo sign
- B. Glucose estimation
- C. Beta-2 transferrin (Correct Answer)
- D. All of the options
Explanation: ***Beta-2 transferrin*** - **Beta-2 transferrin** is the **gold standard** for diagnosing CSF rhinorrhea with **high specificity and sensitivity** - It is present **only in CSF, perilymph, and aqueous humor**, making it highly specific for CSF leak diagnosis - While it requires specialized laboratory analysis and may not be immediately available, it remains the **most reliable confirmatory test** - Modern alternatives include **Beta-trace protein**, which also has high specificity *Glucose estimation* - Historically used as a rapid screening test based on the presence of glucose in CSF - **Major limitation**: **Poor specificity** as nasal mucus, tears, and other secretions also contain glucose, leading to frequent false positives - A positive glucose test is suggestive but **not diagnostic** and requires confirmation with more specific tests - No longer considered the primary diagnostic method due to high false-positive rates *Halo sign* - The **halo sign** (or double ring sign) appears when nasal discharge mixed with blood is placed on filter paper, creating a central blood spot with a clear surrounding ring - **Not specific for CSF** - other watery fluids (tears, saline) mixed with blood can produce similar appearance - Useful as a **bedside screening test** but requires confirmation with biochemical analysis *All of the options* - While multiple tests can be used in the diagnostic workup, they have **different specificities and diagnostic values** - **Beta-2 transferrin** is the definitive diagnostic test, while others serve as screening or supportive tests - Therefore, "All of the options" is incorrect as the question asks for the diagnostic test, which specifically refers to the gold standard
Question 6: Among the following trigeminal nerve divisions, which one is involved in orbital apex syndrome?
- A. Olfactory nerve
- B. Mandibular division of trigeminal nerve
- C. Maxillary division of trigeminal nerve
- D. Ophthalmic division of trigeminal nerve (Correct Answer)
Explanation: ***Ophthalmic division of trigeminal nerve*** - Orbital apex syndrome involves deficits of nerves passing through the **superior orbital fissure** and **optic canal**, which includes the ophthalmic division of the trigeminal nerve (CN V1). - Involvement of CN V1 leads to **sensory loss** in the forehead, upper eyelid, and side of the nose. *Olfactory nerve* - The **olfactory nerve (CN I)** is responsible for the sense of smell and does not pass through the orbital apex. - Its involvement would manifest as **anosmia**, which is not a characteristic feature of orbital apex syndrome. *Maxillary division of trigeminal nerve* - The **maxillary division (CN V2)** exits the skull through the **foramen rotundum** and innervates the midface. - It is generally **not involved** in orbital apex syndrome, as its anatomical course is distinct from the structures within the orbital apex. *Mandibular division of trigeminal nerve* - The **mandibular division (CN V3)** exits the skull through the **foramen ovale** and innervates the lower face and muscles of mastication. - Its involvement is **not associated** with orbital apex syndrome, as it is anatomically distant from the orbital apex.
Question 7: Impulses generated in the taste buds of the tongue reach the cerebral cortex via the
- A. Thalamus (Correct Answer)
- B. Dorsal roots of the first cervical spinal nerve
- C. Hypoglossal nerve
- D. Lingual nerve
Explanation: ***Thalamus*** - The **thalamus** acts as a crucial relay station for almost all sensory information, including taste, before it reaches the **cerebral cortex** for conscious perception. - Taste signals from the cranial nerves (facial, glossopharyngeal, vagus) travel to the **nucleus of the solitary tract** in the brainstem, then to the **ventral posteromedial (VPM) nucleus of the thalamus**, and finally to the **gustatory cortex**. *Dorsal roots of the first cervical spinal nerve* - The dorsal roots of cervical spinal nerves are involved in transmitting **somatosensory information** (touch, pain, temperature, proprioception) from the neck and head region, not taste. - These nerves carry signals from the spinal cord to the brain, whereas taste pathways originate from cranial nerves in the head. *Hypoglossal nerve* - The **hypoglossal nerve (CN XII)** is primarily a **motor nerve** responsible for controlling the muscles of the tongue, essential for speech and swallowing. - It has no direct role in transmitting taste sensations to the cerebral cortex. *Lingual nerve* - The **lingual nerve** is a branch of the **trigeminal nerve (CN V)** and carries **general sensation** (touch, pain, temperature) from the anterior two-thirds of the tongue. - While it runs with the **chorda tympani** (a branch of the facial nerve that carries taste), the lingual nerve itself does not transmit taste signals to the brain.
Question 8: Investigations used for CSF rhinorrhea are all except:
- A. Skull X-ray (Correct Answer)
- B. CT cisternogram
- C. Beta-2 transferrin
- D. Nasal endoscopy
Explanation: ***Skull X-ray*** - A **skull X-ray** is generally not useful for diagnosing **CSF rhinorrhea** as it lacks the detailed soft tissue resolution needed to identify CSF leaks. - It cannot visualize small defects in the skull base or detect the presence of CSF distinct from other nasal secretions. *CT cisternogram* - A **CT cisternogram** is a highly effective imaging modality for localizing **CSF leaks**, involving an intrathecal injection of contrast followed by CT scanning. - It can pinpoint the exact site of the leak in the skull base, which is crucial for surgical planning. *Beta-2 transferrin* - **Beta-2 transferrin** is a protein found almost exclusively in **cerebrospinal fluid (CSF)**, making its detection in nasal discharge diagnostic of CSF rhinorrhea. - This biochemical test offers high specificity for confirming the presence of CSF. *Nasal endoscopy* - **Nasal endoscopy** allows direct visualization of the nasal cavity and can help identify the source of the leak, especially if active dripping is observed. - During the procedure, the Valsalva maneuver or changes in head position can sometimes provoke or increase the flow of CSF, aiding in localization.
Question 9: What test is not used for testing olfaction?
- A. Arnold stick test (Correct Answer)
- B. UPSIT
- C. CC-SIT
- D. Smell diskettes
Explanation: ***Arnold stick test*** - The **Arnold stick test** is primarily used for evaluating **hearing**, specifically for assessing **eardrum mobility** and the integrity of the **ossicular chain**. - It involves a small speculum connected to a rubber bulb, and the movement of the eardrum is observed with a microscope, making it unrelated to olfaction. *UPSIT* - The **University of Pennsylvania Smell Identification Test (UPSIT)** is a widely used and well-validated test for **olfactory function**. - It consists of 40 scratch-and-sniff odorants, and the patient identifies each odor from a set of four choices. *CC-SIT* - The **Cross-Cultural Smell Identification Test (CC-SIT)** is a shorter, 12-item version derived from the UPSIT, designed for **cross-cultural applicability** in testing olfaction. - It also uses a scratch-and-sniff method to assess the ability to identify various odors. *Smell diskettes* - **Smell diskettes**, or smell identification tests using diskettes, are various types of **odor identification kits** where different odors are impregnated onto small disks. - These are common tools used to assess **olfaction** by requiring patients to identify specific smells.
Question 10: In which condition is Young's operation performed?
- A. Allergic rhinitis
- B. Vasomotor rhinitis
- C. Lupus vulgaris
- D. Atrophic rhinitis (Correct Answer)
Explanation: ***Atrophic rhinitis*** - **Young's operation** is a surgical procedure specifically designed to treat severe cases of **atrophic rhinitis**, aiming to narrow the nasal cavity and promote mucosal regeneration. - Involves **closing the nostrils temporarily** for several months to allow healing and reduce crusting and foul odor associated with the condition. *Allergic rhinitis* - This condition is managed primarily with **antihistamines**, **nasal corticosteroids**, and allergen avoidance, not surgical methods like Young's operation. - It is an **inflammatory response** to allergens, causing sneezing, itching, and rhinorrhea, which is distinct from the mucosal atrophy seen in atrophic rhinitis. *Vasomotor rhinitis* - Vasomotor rhinitis is characterized by **non-allergic triggers** like temperature changes or irritants, leading to nasal congestion and rhinorrhea. - Treatment typically involves **topical nasal sprays** (e.g., ipratropium bromide) or lifestyle modifications, not **Young's operation**. *Lupus vulgaris* - Lupus vulgaris is a form of **cutaneous tuberculosis** affecting the skin, primarily treated with **anti-tubercular drugs**, not a nasal surgical procedure. - It presents as chronic, progressive skin lesions and is unrelated to nasal cavity disorders.
Want unlimited practice?
Get full access to all questions, explanations, and performance tracking.
Start For Free