Anatomy
3 questionsCeruminous glands present in the ear are:
When does the rudimentary cochlea develop in the fetus?
External auditory canal is formed by:
NEET-PG 2015 - Anatomy NEET-PG Practice Questions and MCQs
Question 781: Ceruminous glands present in the ear are:
- A. Modified eccrine glands
- B. Modified apocrine glands (Correct Answer)
- C. Mucous gland
- D. Modified holocrine glands
Explanation: ***Modified apocrine glands*** - **Ceruminous glands** in the ear canal are specialized **apocrine glands** responsible for producing cerumen (earwax). - Like other apocrine glands, they secrete their product via **apical budding** of the cell, releasing fragments of the cell along with the secretion [1]. *Modified eccrine glands* - **Eccrine sweat glands** are distributed throughout the skin and produce a watery sweat for thermoregulation [1]. - They secrete their product directly onto the skin surface via **exocytosis**, without loss of cellular material. *Mucous gland* - **Mucous glands** (e.g., salivary glands, respiratory tract glands) produce **mucus**, a viscous secretion primarily for lubrication and protection. - Their secretions are rich in **mucin glycoproteins**, which is distinct from the lipid-rich cerumen. *Modified holocrine glands* - **Holocrine glands** (e.g., sebaceous glands) release their entire cell contents, including lipids and cellular debris, upon cell lysis. - While sebaceous glands contribute to earwax, ceruminous glands themselves operate via an **apocrine mechanism**, not holocrine [1].
Question 782: When does the rudimentary cochlea develop in the fetus?
- A. First week
- B. 4th to 8th week (Correct Answer)
- C. 8th to 12th week
- D. 16 to 20th week
Explanation: 4th to 8th week - The **cochlea** begins its development from the **otic vesicle** around the **4th week** of gestation and undergoes extensive coiling. - By the **8th week**, the cochlea has achieved its characteristic snail-like shape, though further differentiation and maturation continue. *First week* - The first week of embryonic development involves **fertilization**, **cleavage**, and **implantation**, with no organogenesis occurring [1]. - At this stage, the embryo is a **blastocyst**, and specific organ structures like the cochlea have not yet begun to form [1]. *8th to 12th week* - While significant maturation of the inner ear structures occurs during this period, the **rudimentary cochlea** has already formed its basic shape by the 8th week. - This phase involves further differentiation of the **organ of Corti** and development of neural connections, rather than the initial formation of the cochlea itself. *16 to 20th week* - By the 16th to 20th week, the inner ear structures are largely developed and functional, including the **cochlea**, which is capable of responding to sound stimuli. - This period marks the onset of **fetal hearing** and continued fine-tuning of the auditory system, far beyond the rudimentary stage of cochlear development.
Question 783: 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.
Community Medicine
1 questionsUnder NTEP, what is the honorarium given to a DOTS provider after the completion of treatment?
NEET-PG 2015 - Community Medicine NEET-PG Practice Questions and MCQs
Question 781: Under NTEP, what is the honorarium given to a DOTS provider after the completion of treatment?
- A. 150 INR
- B. 500 INR (Correct Answer)
- C. 1000 INR
- D. 250 INR
Explanation: ***500 INR*** - Under the **National Tuberculosis Elimination Programme (NTEP)**, a **DOTS provider** receives an honorarium of **INR 500** upon the successful completion of tuberculosis treatment for a **new TB patient**. - This incentive, revised from the earlier amount of INR 250, aims to recognize the crucial role of DOTS providers in ensuring treatment adherence and successful outcomes. - The increased honorarium reflects the government's commitment to incentivizing community participation in TB elimination. *150 INR* - This amount is **significantly lower than the stipulated honorarium** for a DOTS provider upon treatment completion under current NTEP guidelines. - The correct incentive for successful completion of treatment is INR 500 for new TB cases. *250 INR* - This was the **earlier honorarium amount** under the previous NTEP guidelines, which has since been **revised upward**. - Under the current NTEP incentive structure, the honorarium for treatment completion has been increased to INR 500. *1000 INR* - This amount is **higher than the designated honorarium** for a DOTS provider upon treatment completion under NTEP. - While this figure may apply to other incentive schemes or different milestones, the standard honorarium for new TB case completion is INR 500.
ENT
5 questionsWhich of the following statements about malignant otitis externa is true?
Chemical labyrinthectomy by transtympanic route is done in Meniere's disease using which drug?
Which of the following tests is used to differentiate between cochlear and retrocochlear hearing loss?
Otosclerosis affects which bone?
Which perforation of the tympanic membrane is most commonly seen with tubotympanic CSOM?
NEET-PG 2015 - ENT NEET-PG Practice Questions and MCQs
Question 781: Which of the following statements about malignant otitis externa is true?
- A. Not painful
- B. Common in diabetics and old age (Correct Answer)
- C. Caused by streptococcus
- D. Responds to topical antibiotics alone
Explanation: ***Common in diabetics and old age*** - **Malignant otitis externa** is an aggressive infection primarily affecting the external auditory canal and surrounding structures. - It most commonly occurs in **immunocompromised individuals**, especially **elderly diabetics**, due to impaired immune response and microvascular complications. *Not painful* - Malignant otitis externa is characterized by **severe, unrelenting otalgia (ear pain)** that often worsens at night and is disproportionate to the clinical findings. - The pain is due to the **inflammatory and destructive process** involving cartilage, bone, and nerves. *Caused by streptococcus* - The most common causative organism for malignant otitis externa is **Pseudomonas aeruginosa** (>90% of cases), not Streptococcus. - **Streptococcus species** are more commonly associated with acute otitis media or common skin infections. *Responds to topical antibiotics alone* - Malignant otitis externa requires **prolonged systemic antibiotic therapy** (typically 4-6 weeks of intravenous or oral fluoroquinolones like ciprofloxacin). - Topical antibiotics alone are **insufficient** due to the invasive nature of the infection, which extends beyond the external canal to involve bone and soft tissues.
Question 782: Chemical labyrinthectomy by transtympanic route is done in Meniere's disease using which drug?
- A. Amikacin
- B. Amoxycillin
- C. Cyclosporine
- D. Gentamicin (Correct Answer)
Explanation: ***Gentamicin*** - **Gentamicin** is an **aminoglycoside antibiotic** that is commonly used for chemical labyrinthectomy due to its **ototoxic** properties, particularly its selective toxicity to **vestibular hair cells** at lower doses. - When administered transtympanically, it achieves high concentrations in the **inner ear fluid**, effectively ablating the vestibular function and reducing severe vertigo in **Meniere's disease**. *Amikacin* - **Amikacin** is also an **aminoglycoside antibiotic** with ototoxic potential, but it is typically reserved for severe bacterial infections and is not the primary drug of choice for **chemical labyrinthectomy** in Meniere's disease. - While it can cause hearing loss, **gentamicin** has a more established and preferential effect on the **vestibular system** at therapeutic doses for Meniere's. *Amoxycillin* - **Amoxycillin** is a common **beta-lactam antibiotic** used for bacterial infections, and it does not possess **ototoxic** properties that would make it suitable for chemical labyrinthectomy. - It is primarily known for its antibacterial action and has no role in the management of vertigo in **Meniere's disease** via transtympanic administration. *Cyclosporine* - **Cyclosporine** is an **immunosuppressant drug** used to prevent organ rejection and treat autoimmune conditions; it does not have properties for chemical ablation of the labyrinth. - While some autoimmune components are sometimes considered in Meniere's disease, cyclosporine is not used for **transtympanic chemical labyrinthectomy**.
Question 783: Which of the following tests is used to differentiate between cochlear and retrocochlear hearing loss?
- A. Recruitment
- B. Threshold tone decay test
- C. Evoked response audiometry (Correct Answer)
- D. SISI test
Explanation: **Evoked response audiometry** - **Evoked response audiometry (ERA)**, specifically **Auditory Brainstem Response (ABR)** or **Brainstem Evoked Response Audiometry (BERA)**, is the gold standard for differentiating between cochlear and retrocochlear hearing loss. - ABR measures electrical activity from the auditory nerve and brainstem in response to sound, allowing for differentiation between **cochlear pathology** (normal ABR latencies with hearing loss) and **retrocochlear pathology** (prolonged interpeak latencies, absent waves, or abnormal waveform morphology suggestive of auditory nerve or brainstem lesion). - Classic findings in retrocochlear lesions include prolonged I-V interpeak latency or absent Wave V. *SISI test* - The **Short Increment Sensitivity Index (SISI) test** assesses the ability to detect small (1 dB) increments in sound intensity superimposed on a continuous tone. - A **high SISI score (>70%)** indicates **cochlear dysfunction** due to recruitment phenomenon, while a **low score (<20%)** may suggest retrocochlear pathology. - However, it does not directly differentiate between cochlear and retrocochlear lesions with the same specificity and sensitivity as ABR. *Threshold tone decay test* - The **Tone Decay Test (TDT)** measures the ability to sustain the perception of a continuous pure tone presented at or near threshold level. - **Significant tone decay (>30 dB in 60 seconds)** suggests **retrocochlear pathology** due to auditory nerve fatigue, making it useful for screening. - While helpful, it is less precise, sensitive, and specific than ABR for definitive differentiation and may have false positives. *Recruitment* - **Recruitment** is an abnormal growth in the perception of loudness, where a small increase in sound intensity leads to a disproportionately large increase in perceived loudness. - It is a classic sign of **cochlear hearing loss**, particularly associated with outer hair cell damage (sensory hearing loss). - Its presence confirms cochlear pathology but its absence does not confirm retrocochlear lesions, making it less reliable as a differentiating test compared to ABR.
Question 784: Otosclerosis affects which bone?
- A. Stapes (Correct Answer)
- B. Incus
- C. Malleus
- D. Cochlea
Explanation: ***Stapes*** - **Otosclerosis** is a condition characterized by abnormal bone growth in the middle ear, specifically around the **stapes footplate**. - This abnormal growth fixates the stapes, preventing it from vibrating properly and leading to **conductive hearing loss**. - **Fenestral otosclerosis** (most common type) directly affects the oval window and stapes footplate. *Incus* - The **incus** is the middle ossicle in the chain, between the malleus and the stapes. - While it can be affected by other middle ear pathologies, otosclerosis primarily targets the **stapes**. *Malleus* - The **malleus** is the outermost ossicle, attached to the eardrum. - Its involvement in otosclerosis is rare and indirect, as the primary site of disease is the **stapes**. *Cochlea* - **Cochlear (retrofenestral) otosclerosis** can occur but is less common and typically causes **sensorineural hearing loss**. - The classic presentation of otosclerosis involves **stapedial fixation** causing conductive hearing loss, not primary cochlear involvement.
Question 785: 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.
Physiology
1 questionsWhat is the intensity in decibel of normal conversation in humans?
NEET-PG 2015 - Physiology NEET-PG Practice Questions and MCQs
Question 781: What is the intensity in decibel of normal conversation in humans?
- A. 30dB
- B. 60dB (Correct Answer)
- C. 90dB
- D. 150dB
Explanation: ***60dB*** - The sound intensity of **normal human conversation** is typically around **60 decibels (dB)**. - This level is considered **moderate** and is comfortably audible without causing discomfort or hearing damage. *30dB* - A sound intensity of **30dB** is characteristic of a **quiet whisper** or a **soft rustle of leaves**. - This level is much **quieter** than a normal conversation and would require closer proximity to be clearly heard. *90dB* - **90dB** represents a significantly **louder sound**, comparable to that of a **lawnmower** or a **heavy truck** passing by. - Prolonged exposure to sounds at this intensity can start to cause **hearing damage**. *150dB* - **150dB** is an **extremely loud** and potentially **painful** sound level, similar to a **jet engine at takeoff** or a **firecracker** exploding nearby. - Exposure to sounds this intense can cause **immediate and permanent hearing loss**.