Anatomy
4 questionsExternal auditory canal is formed by:
Which anatomical structure lies between the bulla ethmoidalis and the uncinate process of the ethmoid?
What lies between the middle and inferior turbinate?
What is the narrowest part of the nasal cavity?
NEET-PG 2015 - Anatomy NEET-PG Practice Questions and MCQs
Question 691: External auditory canal is formed by:
- A. 1st branchial groove (Correct Answer)
- B. 1st visceral pouch
- C. 2nd branchial groove
- D. 2nd visceral pouch
Explanation: 1st branchial groove - The **external auditory canal** is primarily derived from the **first branchial (pharyngeal) groove** during embryonic development [1]. - This groove deepens to form the primitive external auditory meatus, which later develops into the adult external auditory canal [1]. *1st visceral pouch* - The **first pharyngeal (visceral) pouch** gives rise to structures like the **eustachian tube** (auditory tube) and the **middle ear cavity** (tympanic cavity) [1]. - It does not contribute to the formation of the external auditory canal. *2nd branchial groove* - The **second pharyngeal (branchial) groove** contributes to the formation of the **cervical sinus**, which normally obliterates. - Persistence of this groove can lead to **cervical cysts or fistulae**, but it is not involved in ear development. *2nd visceral pouch* - The **second pharyngeal (visceral) pouch** develops into the **palatine tonsils** and its fossa. - It plays no role in the formation of the external auditory canal or other ear structures.
Question 692: Which anatomical structure lies between the bulla ethmoidalis and the uncinate process of the ethmoid?
- A. Ethmoidal infundibulum (Correct Answer)
- B. Bulla ethmoidalis
- C. Uncinate process of ethmoid
- D. Maxillary sinus
Explanation: ***Ethmoidal infundibulum*** - The **ethmoidal infundibulum** is a curved, three-dimensional space located within the **lateral wall of the nasal cavity**. - It forms a critical drainage pathway, often leading to the opening of the **maxillary sinus** and serving as the primary outflow tract for the anterior ethmoidal air cells. *Bulla ethmoidalis* - The **bulla ethmoidalis** is the largest and most constant anterior ethmoid air cell, bulging into the middle meatus. - It lies *superior and posterior* to the ethmoidal infundibulum, forming one of its boundaries, not the space itself. *Uncinate process of ethmoid* - The **uncinate process** is a sickle-shaped bony lamella that forms the *anterior and inferior boundary* of the ethmoidal infundibulum. - It helps define the pathway for drainage but is a bony structure, not the intervening space. *Maxillary sinus* - The **maxillary sinus** is a paranasal sinus located within the maxilla, which drains into the posterior part of the ethmoidal infundibulum or hiatus semilunaris. - It is a separate air-filled cavity, not the anatomical space between the bulla ethmoidalis and uncinate process.
Question 693: What lies between the middle and inferior turbinate?
- A. Middle meatus (Correct Answer)
- B. Superior meatus
- C. Inferior meatus
- D. Hiatus semilunaris
Explanation: ***Middle meatus*** - The **nasal meatuses** are passages in the nasal cavity that lie inferolateral to a corresponding **turbinate**. - Therefore, the **middle meatus** is located directly beneath the **middle turbinate** and superior to the **inferior turbinate**. *Superior meatus* - The **superior meatus** lies below the **superior turbinate**. - It drains the posterior ethmoid air cells and the sphenoid sinus. *Hiatus semilunaris* - The **hiatus semilunaris** is a curved opening located within the **middle meatus**. - It is an important drainage pathway for the frontal sinus, maxillary sinus, and anterior ethmoid air cells. *Inferior meatus* - The **inferior meatus** lies below the **inferior turbinate**. - It receives the opening of the **nasolacrimal duct**.
Question 694: What is the narrowest part of the nasal cavity?
- A. Vestibule
- B. Choanae
- C. Inferior turbinate
- D. Internal nasal valve area (Correct Answer)
Explanation: ***Internal nasal valve area*** - The **internal nasal valve** (ostium internum) is the **narrowest part of the nasal cavity**, located approximately 1.3 cm from the nostril - Formed by the **septal cartilage medially**, **upper lateral cartilage laterally**, **nasal floor inferiorly**, and **anterior head of inferior turbinate posteriorly** - The angle between the septum and upper lateral cartilage is typically **10-15 degrees**, creating the narrowest cross-sectional area - Accounts for approximately **50% of total nasal airway resistance** and is clinically the most critical site for airflow regulation - **Clinical significance**: Site of nasal valve collapse in breathing disorders *Vestibule* - The **nasal vestibule** is the most anterior part of the nasal cavity lined with **keratinized stratified squamous epithelium** and **vibrissae** (nasal hairs) - While it is a narrow region, it is **NOT the narrowest part** of the nasal cavity - Acts as the entrance to the nasal cavity but has a larger cross-sectional area than the internal nasal valve *Choanae* - The **choanae** are the **posterior openings** of the nasal cavity that open into the nasopharynx - They represent a transition point for airflow but are relatively **wide openings**, not the narrowest part *Inferior turbinate* - The **inferior turbinate** is a bony projection covered with erectile tissue that increases surface area for warming and humidifying air - While it can become engorged and narrow the airway pathologically, anatomically it does not constitute the narrowest fixed point of the nasal passage
ENT
5 questionsWhich perforation of the tympanic membrane is most commonly seen with tubotympanic CSOM?
Most common cause of otitis externa is
Which of the following is a cause of objective tinnitus?
Hitselberger's sign is seen in?
Which of the following statements about vasomotor rhinitis is NOT true?
NEET-PG 2015 - ENT NEET-PG Practice Questions and MCQs
Question 691: Which perforation of the tympanic membrane is most commonly seen with tubotympanic CSOM?
- A. Central (Correct Answer)
- B. Anterosuperior
- C. Posterosuperior
- D. Posteroinferior
Explanation: ***Central*** - A **central perforation** of the tympanic membrane is the most common type seen in **tubotympanic chronic suppurative otitis media (CSOM)**. - This type of perforation involves the **pars tensa** of the tympanic membrane, leaving an intact annulus. *Anterosuperior* - While perforations can occur anywhere, an **anterosuperior perforation** is not the hallmark of tubotympanic CSOM. - This location does not specifically correlate with the characteristic inflammatory patterns seen in tubotympanic disease. *Posterosuperior* - A **posterosuperior perforation** is more often associated with **atticoantral CSOM** due to **cholesteatoma formation**. - **Cholesteatoma** typically begins in the pars flaccida or posterosuperior pars tensa, which is different from tubotympanic CSOM. *Posteroinferior* - A **posteroinferior perforation** is not the most typical presentation for tubotympanic CSOM. - This location does not specifically differentiate it from other forms of otitis media or reflect the primary pathology of tubotympanic disease.
Question 692: Most common cause of otitis externa is
- A. Fungal infection
- B. Bacterial infection (Correct Answer)
- C. Seborrheic disease
- D. Herpes Zoster
Explanation: ***Bacterial infection*** - The most common pathogens causing **otitis externa** are bacteria, primarily **Pseudomonas aeruginosa** and **Staphylococcus aureus**. - This condition, often called "swimmer's ear," is favored by moisture in the ear canal, which creates a conducive environment for bacterial growth. *Fungal infection* - While fungal infections (otomycosis) can cause otitis externa, they are **less common** than bacterial causes. - Fungi like *Aspergillus* and *Candida* are typically involved, often in immunocompromised individuals or after prolonged antibiotic use. *Seborrheic disease* - **Seborrheic dermatitis** can affect the ear canal and surrounding skin, leading to flaking, itching, and inflammation. - However, it is a primary skin condition and does not directly cause infectious otitis externa, although it can predispose to secondary infections. *Herpes Zoster* - **Herpes zoster oticus** (Ramsay Hunt syndrome) is a viral infection affecting the facial nerve, causing a painful rash, facial paralysis, and hearing loss. - It is a specific viral etiology with distinct neurological symptoms and is not a common cause of general otitis externa.
Question 693: Which of the following is a cause of objective tinnitus?
- A. Impacted Wax
- B. Carotid artery aneurysm (Correct Answer)
- C. Meniere's disease
- D. Ototoxic drugs
Explanation: ***Carotid artery aneurysm*** - An **aneurysm** of the **carotid artery** can cause pulsatile tinnitus that is audible to others (objective) due to turbulent blood flow. - The sounds originate from vascular structures within or near the ear, making them detectable by a clinician. *Impacted Wax* - **Impacted cerumen** is a common cause of **subjective tinnitus**, where the sound is heard only by the patient. - It can muffle external sounds and alter the perception of internal body sounds, but it does not produce a sound audible to others. *Meniere's disease* - **Meniere's disease** is characterized by **subjective tinnitus**, along with vertigo, hearing loss, and aural fullness. - The tinnitus in Meniere's is typically a low-pitched roaring or buzzing sound, audible only to the affected individual. *Ototoxic drugs* - **Ototoxic drugs** (e.g., aspirin, aminoglycosides) commonly induce **subjective tinnitus** as a side effect. - These medications primarily damage inner ear structures, leading to perceived sounds that are not externally measurable.
Question 694: Hitselberger's sign is seen in?
- A. Glomus Tumour
- B. Nasal angiofibroma
- C. Acute suppurative otitis media
- D. Acoustic neuroma (Correct Answer)
Explanation: ***Acoustic neuroma*** - Hitselberger's sign is an area of **hypoesthesia** or **anesthesia** in the **posterosuperior portion of the external auditory canal**. - Acoustic neuromas (vestibular schwannomas) arise from the **vestibular portion of CN VIII** in the internal auditory canal. - This sign results from involvement of the **sensory fibers of the nervus intermedius** (sensory branch associated with the facial nerve) due to close anatomical proximity in the cerebellopontine angle. - This symptom, also known as the **"ear canal sign,"** is relatively specific for acoustic neuroma. *Glomus Tumour* - Glomus tumors are **highly vascular benign tumors** of the **middle ear** that present with **pulsatile tinnitus** and conductive hearing loss. - While they can affect cranial nerves, Hitselberger's sign is not a characteristic presentation. *Nasal angiofibroma* - Nasal angiofibromas are **benign, highly vascular tumors** found in the **nasopharynx**, primarily affecting adolescent males. - They typically present with **epistaxis** and **nasal obstruction** and do not cause Hitselberger's sign. *Acute suppurative otitis media* - Acute suppurative otitis media is an **infection of the middle ear** causing earache, fever, and hearing loss. - It does not involve the cerebellopontine angle or sensory innervation of the external auditory canal in a way that would lead to Hitselberger's sign.
Question 695: Which of the following statements about vasomotor rhinitis is NOT true?
- A. It is due to parasympathetic overactivity
- B. Resistant cases may need cryotherapy
- C. It may lead to hypertrophic rhinitis
- D. It is caused by an allergic reaction (Correct Answer)
Explanation: ***It is caused by an allergic reaction.*** - Vasomotor rhinitis, also known as nonallergic rhinitis, is characterized by symptoms similar to allergic rhinitis but is **not mediated by an allergic reaction** or an IgE-mast cell response. - Its etiology is related to the **dysregulation of the autonomic nervous system**, specifically an imbalance in the vascular tone of nasal blood vessels, rather than an allergic trigger. *It is due to parasympathetic overactivity* - **Parasympathetic overactivity** is a recognized underlying mechanism in vasomotor rhinitis, leading to increased vascular permeability and glandular secretion. - This overactivity results in symptoms such as **nasal congestion**, rhinorrhea, and sneezing, mimicking allergic rhinitis without an identifiable allergen. *Resistant cases may need cryotherapy* - For severe and **medically refractory cases** of vasomotor rhinitis, **cryotherapy** (specifically cryoablation of the posterior nasal nerve) can be a treatment option. - This procedure targets the nerves responsible for parasympathetic outflow to the nasal mucosa, thereby reducing symptoms like rhinorrhea and congestion. *It may lead to hypertrophic rhinitis* - Chronic inflammation and vascular engorgement associated with long-standing vasomotor rhinitis can lead to **mucosal hypertrophy**, particularly of the inferior turbinates. - This condition, known as **hypertrophic rhinitis**, can exacerbate nasal obstruction and may require surgical intervention to improve airflow.
Internal Medicine
1 questionsSaddle nose deformity is seen in?
NEET-PG 2015 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 691: Saddle nose deformity is seen in?
- A. Primary Syphilis
- B. Secondary Syphilis
- C. Tertiary Syphilis (Correct Answer)
- D. Lupus Vulgaris
Explanation: ***Tertiary Syphilis*** - **Saddle nose deformity** is a characteristic late manifestation of **tertiary syphilis** due to destructive lesions (gummas) affecting the nasal cartilage and bone [1], [2]. - It results from the **collapse of the nasal bridge**, leading to a flattened appearance [2]. *Primary Syphilis* - Characterized by a **chancre**, a painless ulcer, usually at the site of infection [1]. - This stage does not involve destructive lesions of the nose. *Secondary Syphilis* - Presents with a **widespread rash**, lymphadenopathy, and mucous patches [1]. - While systemic, it typically does not cause structural damage like saddle nose deformity. *Lupus Vulgaris* - This is a **cutaneous form of tuberculosis**, characterized by chronic, destructive skin lesions. - While it can cause facial disfigurement, saddle nose deformity is not a typical feature of lupus vulgaris.