**Question:** A 20-year-old male presents with throat pain and easy fatigability of his voice. Indirect laryngeal examination revealed both cords approximately well but leaving a triangular gap in the interarytenoid. Your diagnosis is:

A. Vocal cord paresis
B. Vocal cord paralysis
C. Vocal cord nodule
D. Vocal cord polyp

**Correct Answer:** **D. Vocal cord polyp**

**Core Concept:**

The triangular gap in the interarytenoid area, observed during indirect laryngeal examination, is a characteristic finding in vocal cord polyp. Vocal cord polyps are benign, overgrowths of the vocal cord surface epithelium and submucosa. They are often idiopathic in origin, but may also be caused by excessive vocal abuse, irritants, or underlying vocal cord inflammation.

**Why the Correct Answer is Right:**

Vocal cord polyps can cause throat pain and easy fatigability of the voice due to mechanical obstruction and inflammation-induced irritation of the vocal cord. The presence of a triangular gap in the interarytenoid area during indirect laryngeal examination is a key clinical sign pointing towards vocal cord polyp.

**Why Each Wrong Option is Incorrect:**

1. Vocal cord paresis (A) and paralysis (B) are conditions resulting from lesions affecting the motor nerves to the vocal cords, which would not typically present with a triangular gap in the interarytenoid area during examination.
2. Vocal cord nodules (C) are raised, raised growths on the vocal cords, not causing a triangular gap.
3. Vocal cord polyps (D) are a specific type of vocal cord lesion, characterized by a triangular gap in the interarytenoid area during examination.

**Why the Correct Answer is Right:**

Vocal cord polyp is the correct answer because:

* Indicates the presence of a triangular gap in the interarytenoid area during indirect laryngeal examination.
* Causes throat pain and voice fatigue due to mechanical obstruction and inflammation-induced irritation of the vocal cords.
* The patient's age of 20 years is suggestive of an idiopathic cause for the polyp, although not a definitive criteria.

**Why Each Wrong Option is Incorrect:**

* Vocal cord paresis and paralysis (A & B) are caused by lesions affecting the motor nerves to the vocal cords, which would not typically present with a triangular gap in the interarytenoid area during examination.
* Vocal cord nodules (C) are raised, elevated growths on the vocal cords, not causing a triangular gap in the interarytenoid area during examination.
* Vocal cord polyp (D) is a specific type of vocal cord lesion characterized by a triangular gap in the interarytenoid area during examination, causing throat pain and voice fatigue due to mechanical obstruction and inflammation-induced irritation of the vocal cords.