Step 1: Definition of "tic douloureux."
Tic douloureux, also known as trigeminal neuralgia, is a condition causing sudden, intense, sharp pain unilaterally on the face. This condition typically stems from trigeminal nerve dysfunction.
Step 2: Evaluation of options.
- (1) Trigeminal nerve: Correct. The trigeminal nerve mediates facial sensation and is most frequently implicated in tic douloureux.
- (2) Glossopharyngeal nerve: Incorrect. This nerve affects the throat and ear; it is not associated with tic douloureux.
- (3) Facial nerve: Incorrect. The facial nerve controls facial musculature but does not produce the sharp, shooting pain of tic douloureux.
- (4) Trochlear nerve: Incorrect. The trochlear nerve governs eye movement, not facial sensation.
Step 3: Determination.
Option (1) is the correct answer, as the trigeminal nerve is the nerve most commonly involved in tic douloureux.