Which of the following is NOT associated with a Tonic Pupil?

• A. Vermiform movement of the iris
• B. Acutely dilated pupil with light near dissociation
• C. Diminished Deep tendon reflex
• D. Hypersensitivity of the adrenergic receptors on the iris

Answer: (D)

Tonic pupil results from loss of parasympathetic input to the iris sphincter from the ciliary ganglion. This denervation causes a dilated pupil that constricts poorly to light but may slowly tighten with accommodation, and the iris can show vermiform, or worm-like, movements due to irregular sphincter activity. Diminished deep tendon reflexes can accompany the condition as part of a broader autonomic neuropathy. A hallmark of this condition is denervation hypersensitivity to acetylcholine, so very dilute pilocarpine will provoke constriction. The sympathetic side, governed by adrenergic receptors on the iris dilator, is not the site of the problem in tonic pupil; hypersensitivity of those adrenergic receptors isn’t a feature.