Diseases of the Larynx Practice Questions

Q: Tubercular laryngitis primarily affects which part of the larynx?

Posterior commissure of larynx. ### Explanation **Correct Option: B. Posterior commissure of larynx** Laryngeal tuberculosis is almost always secondary to pulmonary tuberculosis. The infection reaches the larynx via **bronchogenic spread** (infected sputum). When a patient is in a recumbent or supine position, the infected sputum pools in the most dependent part of the larynx, which is the **posterior commissure** (interarytenoid area). The bacilli invade the mucosa, leading to the classic "mammillated" (pachydermia-like) appearance. The posterior part of the larynx is also highly vascular and has a high density of mucous glands, making it more susceptible to the inflammatory process of TB. **Analysis of Incorrect Options:** * **A. Anterior commissure:** This area is typically spared in tuberculosis but is a common site for the spread of laryngeal carcinoma and the formation of laryngeal webs. * **C. Anywhere within the larynx:** While TB can involve other structures (like the epiglottis or vocal cords), it has a distinct predilection for the posterior glottis. It is not a random distribution. * **D. Superior surface of larynx:** This is not a standard anatomical term used to describe the primary site of TB infection. The epiglottis (part of the superior larynx) is involved in the "lupoid" variety of TB, but the posterior commissure remains the most common site overall. **Clinical Pearls for NEET-PG:** * **Classic Appearance:** "Mouse-nibbled" ulcers on the vocal cords and a "Turban-shaped" epiglottis (due to edema). * **Symptoms:** Painful swallowing (**Odynophagia**) is a hallmark, often referred to the ear via the vagus nerve. * **Diagnosis:** Sputum for AFB is the most important initial test; Chest X-ray usually shows active pulmonary cavitation. * **Treatment:** Standard Anti-Tubercular Therapy (ATT). The laryngeal lesions usually heal rapidly once systemic treatment begins.

Q: Which one of the following conditions is considered to be definitely precancerous in the larynx?

Leukoplakia. **Explanation:** **Leukoplakia** is the correct answer because it is a clinical term for a white patch on the mucosal surface that cannot be characterized clinically or pathologically as any other disease. In the larynx, it represents a spectrum of epithelial changes ranging from simple hyperplasia and hyperkeratosis to **dysplasia**, carcinoma-in-situ, and invasive squamous cell carcinoma. Histologically, the presence of dysplasia is the most significant predictor of malignant transformation, making it a definitive precancerous condition. **Why the other options are incorrect:** * **Vocal Nodules:** These are benign, inflammatory reactive lesions (usually bilateral) caused by mechanical trauma from vocal abuse (Screamer’s nodes). They have no malignant potential. * **Vocal Polyps:** These are unilateral inflammatory lesions resulting from acute vocal trauma or smoking. Like nodules, they are benign and do not undergo malignant transformation. * **Subglottic Hemangiomas:** These are benign vascular tumors, most commonly seen in infants. While they can cause airway obstruction, they are not neoplastic precursors to laryngeal cancer. **NEET-PG High-Yield Pearls:** * **Pachydermia Laryngis:** A form of chronic hypertrophic laryngitis (often due to GERD) characterized by interarytenoid thickening; it is generally **not** considered precancerous. * **Adult-Onset Recurrent Respiratory Papillomatosis (RRP):** Caused by HPV 6 and 11; it has a small but documented risk of malignant transformation (unlike the juvenile form). * **Erythroplakia:** Though less common than leukoplakia in the larynx, a red velvety patch (erythroplakia) carries a significantly **higher risk** of harboring malignancy at the time of biopsy. * **Main Risk Factors:** Smoking and alcohol consumption are the primary synergistic triggers for laryngeal precancerous lesions.

Q: Which muscle is the primary abductor of the vocal cords?

Posterior cricoarytenoid. **Explanation:** The intrinsic muscles of the larynx are responsible for controlling the position and tension of the vocal cords. The **Posterior Cricoarytenoid (PCA)** is the **only abductor** of the vocal cords. It originates from the posterior surface of the cricoid lamina and inserts into the muscular process of the arytenoid cartilage. Upon contraction, it rotates the arytenoids laterally, opening the rima glottidis. Because it is the sole muscle responsible for opening the airway, it is often referred to as the **"Safety Muscle of the Larynx."** **Analysis of Incorrect Options:** * **Thyroarytenoid:** This muscle forms the bulk of the vocal fold. Its medial fibers (Vocalis) help in fine-tuning tension, but its primary action is to **shorten and relax** the vocal cords. * **Lateral Cricoarytenoid:** This is the primary **adductor** of the vocal cords. It rotates the arytenoids medially to close the glottis (the opposite action of the PCA). * **Cricothyroid:** This is the only intrinsic muscle supplied by the **External Laryngeal Nerve** (all others are supplied by the Recurrent Laryngeal Nerve). Its primary function is to **tensor** the vocal cords by tilting the thyroid cartilage forward. **High-Yield Clinical Pearls for NEET-PG:** * **Nerve Supply:** All intrinsic muscles are supplied by the **Recurrent Laryngeal Nerve (RLN)**, except the Cricothyroid. * **Semon’s Law:** In progressive RLN injury, the abductor fibers (PCA) are more susceptible and paralyzed first compared to the adductor fibers. * **Unilateral RLN Palsy:** The vocal cord assumes a paramedian position. * **Bilateral RLN Palsy:** This is a surgical emergency because both PCAs are paralyzed, leading to a closed airway and inspiratory stridor.

Q: Topical mitomycin C is used to aid which of the following treatments?

Treatment of laryngotracheal stenosis. **Explanation:** **Mitomycin C (MMC)** is a potent chemotherapeutic agent derived from *Streptomyces caespitosus*. In ENT, it is used topically for its ability to inhibit **fibroblast proliferation** and protein synthesis, thereby preventing the formation of excessive scar tissue (fibrosis). 1. **Why Option B is Correct:** In **Laryngotracheal Stenosis**, the primary challenge is the recurrence of narrowing due to exuberant granulation tissue and scarring after surgical dilation or resection. Topical application of MMC (typically 0.4 mg/ml) to the denuded area post-surgery inhibits collagen synthesis, maintaining the patency of the airway and reducing the rate of restenosis. 2. **Why Other Options are Incorrect:** * **A. Angiofibroma:** This is a highly vascular benign tumor. Treatment is primarily surgical excision (often with preoperative embolization). MMC has no role in managing vascular tumors. * **C. Skull Base Osteomyelitis:** This is a severe infection (usually fungal or bacterial). Treatment requires long-term systemic antibiotics/antifungals and surgical debridement, not anti-proliferative agents. * **D. Sturge-Weber Syndrome:** This is a neurocutaneous disorder characterized by port-wine stains and vascular malformations. MMC does not address the underlying vascular pathology. **High-Yield Clinical Pearls for NEET-PG:** * **Other ENT uses of MMC:** Used in **Dacryocystorhinostomy (DCR)** to prevent closure of the osteotomy site, in **Choanal Atresia** surgery, and during **Myringotomy** to keep the perforation patent longer. * **Mechanism:** It acts as an alkylating agent that cross-links DNA. * **Application:** It is applied topically via a soaked cottonoid for a brief period (usually 2–5 minutes) to minimize systemic toxicity.

Q: A 4-year-old child presents to the emergency department with high-grade fever, respiratory difficulty, and noisy breathing. An X-ray of his neck is shown below. What is the most probable diagnosis?

Epiglottitis. ***Epiglottitis*** - **High-grade fever**, **respiratory difficulty**, and **noisy breathing** in a child form the classic triad of epiglottitis, often caused by **Haemophilus influenzae type b**. - The lateral neck X-ray shows the characteristic **"thumbprint sign"** indicating swollen epiglottis, which is pathognomonic for epiglottitis. *Recurrent papillomatosis* - Typically presents with **progressive hoarseness** and **chronic respiratory symptoms** rather than acute high fever. - X-ray would show **multiple nodular lesions** in the larynx, not the thumbprint sign of epiglottal swelling. *Croup* - Usually presents with **barking cough** and **low-grade fever**, not the high-grade fever seen here. - Lateral neck X-ray would show the **"steeple sign"** (subglottic narrowing), not the thumbprint sign of epiglottal swelling. *Tonsillitis* - Primarily causes **sore throat** and **difficulty swallowing** rather than respiratory distress and noisy breathing. - X-ray findings would not show epiglottal involvement; diagnosis is typically made by **clinical examination** of enlarged tonsils.

Q: A 55-year-old smoker presents with a low-pitched voice. Endoscopy reveals a mass limited to the left vocal cord. Biopsy is suggestive of laryngeal cancer, T1N0. What is the treatment of choice?

Radiotherapy. **Explanation:** The patient presents with **Early Glottic Cancer (T1N0M0)**, where the tumor is limited to the vocal cord with normal mobility. The primary goal in treating early laryngeal cancer is **cure with organ preservation** and maintenance of voice quality. **1. Why Radiotherapy (RT) is the Correct Choice:** For T1 glottic lesions, both **Radiotherapy** and **Endoscopic Laser Excision** (Transoral Laser Microsurgery - TLM) are considered standard treatments of choice, offering excellent local control rates (>90%). RT is often preferred when the lesion involves the anterior commissure or when a superior functional voice outcome is desired, as it preserves the mucosal wave better than surgical excision. **2. Why Other Options are Incorrect:** * **Vertical Partial Hemilaryngectomy:** This is an open surgical procedure. While oncologically sound, it is more invasive than RT or TLM and is generally reserved for specific recurrences or cases where endoscopic access is impossible. * **Chemotherapy:** Chemotherapy is not used as a primary single-modality treatment for early-stage (T1-T2) laryngeal cancer. It is typically reserved for advanced stages (T3-T4) as part of concurrent chemoradiotherapy (organ preservation protocols). * **Total Laryngectomy with Neck Dissection:** This is a radical, mutilating surgery reserved for advanced (T4a) disease or salvage after failed radiotherapy. It is contraindicated in T1 disease where the larynx can be easily saved. **Clinical Pearls for NEET-PG:** * **T1a:** Tumor limited to one vocal cord. * **T1b:** Tumor involves both vocal cords. * **T2:** Tumor extends to supraglottis/subglottis or impaired cord mobility (but not fixed). * **T3:** Vocal cord fixation (requires RT/Chemo or surgery). * **Most common site** of laryngeal cancer: **Glottis** (best prognosis due to sparse lymphatics). * **Most common pathology:** Squamous Cell Carcinoma.

Q: Which of the following statements is true regarding congenital subglottic stenosis?

All of the above.. **Explanation:** Congenital subglottic stenosis (SGS) is the third most common congenital anomaly of the larynx and the most common cause of laryngeal stenosis requiring tracheostomy in infants. It occurs due to the failure of the laryngeal lumen to recanalize during embryonic development. **Breakdown of Options:** * **Options A & B (Diagnostic Criteria):** The subglottis is the narrowest part of the pediatric airway. Diagnosis is based on the diameter of the cricoid ring. In a **full-term neonate**, a diameter **<4 mm** is considered stenotic. In a **premature neonate**, the threshold is **<3 mm**. These measurements are typically confirmed using age-appropriate endotracheal tubes or bronchoscopy. * **Option C (Clinical Presentation):** Unlike laryngomalacia (where the voice may be muffled) or vocal cord palsy (where the cry is weak/breathy), the vocal cords in SGS are typically normal. Therefore, the **cry is usually normal**, but the child presents with **biphasic stridor** and respiratory distress. Since all statements are clinically accurate, **Option D** is the correct answer. **High-Yield Clinical Pearls for NEET-PG:** * **Grading:** The **Cotton-Myer Classification** is used to grade the severity based on the percentage of luminal obstruction (Grade I to IV). * **Most Common Site:** The stenosis most commonly involves the **cricoid cartilage** (the only complete cartilaginous ring). * **Associated Syndrome:** Frequently associated with **Down Syndrome** (Trisomy 21), where the subglottis is naturally smaller. * **Management:** Mild cases (Grade I/II) are managed conservatively; severe cases (Grade III/IV) may require **Laryngotracheal Reconstruction (LTR)** or **Cricotracheal Resection (CTR)**.

Question 1

Tubercular laryngitis primarily affects which part of the larynx?

Accepted Answer

Posterior commissure of larynx

Answer

Anterior commissure

Answer

Anywhere within the larynx

Answer

Superior surface of larynx

Question 2

A 30-year-old female presented with stridor following an upper respiratory infection. Laryngoscopy shows a glottic gap of 3 mm. Which of the following is NOT a management option?

Accepted Answer

Type I thyroplasty

Answer

Tracheostomy

Answer

Type II thyroplasty

Answer

Cordectomy

Question 3

Injury of which nerve most commonly leads to vocal cord paralysis?

Accepted Answer

Recurrent laryngeal

Answer

External laryngeal

Answer

Internal laryngeal

Answer

Superior laryngeal

Question 4

Which one of the following conditions is considered to be definitely precancerous in the larynx?

Accepted Answer

Leukoplakia

Answer

Vocal nodules

Answer

Subglottic hemangiomas

Answer

Vocal polyp

Question 5

Which muscle is the primary abductor of the vocal cords?

Accepted Answer

Posterior cricoarytenoid

Answer

Thyroarytenoid

Answer

Lateral cricoarytenoid

Answer

Cricothyroid

Question 6

Topical mitomycin C is used to aid which of the following treatments?

Accepted Answer

Treatment of laryngotracheal stenosis

Answer

Endoscopic treatment of angiofibroma

Answer

Skull base osteomyelitis

Answer

Sturge-Weber syndrome

Question 7

A patient with hoarseness of voice was found to be having pachydermia laryngis. All of the following are true except?

Accepted Answer

It is a hyperkeratotic lesion present within the anterior two-third of the vocal cords

Answer

It is not a premalignant lesion

Answer

Diagnosis is made by biopsy

Answer

On microscopy it shows acanthosis and hyperkeratosis

Question 8

A 4-year-old child presents to the emergency department with high-grade fever, respiratory difficulty, and noisy breathing. An X-ray of his neck is shown below. What is the most probable diagnosis?

Accepted Answer

Epiglottitis

Answer

Recurrent papillomatosis

Answer

Croup

Answer

Tonsillitis

Question 9

A 55-year-old smoker presents with a low-pitched voice. Endoscopy reveals a mass limited to the left vocal cord. Biopsy is suggestive of laryngeal cancer, T1N0. What is the treatment of choice?

Accepted Answer

Radiotherapy

Answer

Vertical partial hemilaryngectomy

Answer

Chemotherapy

Answer

Total laryngectomy with cervical lymph node dissection

Question 10

Which of the following statements is true regarding congenital subglottic stenosis?

Accepted Answer

All of the above.

Answer

Diagnosed if subglottic diameter is less than 4mm in a full-term neonate.

Answer

Diagnosed if subglottic diameter is less than 3mm in a premature neonate.

Answer

Cry is normal.

Diseases of the Larynx — MCQs

Diseases of the Larynx — MCQs

On this page

Practice by Chapter

Want unlimited practice?