To the Editor.—The traction test has been emphasized in the clinical investigation of deficient ocular rotations as an important aid in differentiating between deficiencies due to neurogenic or myogenic weakness and those caused by restrictions.1,2 This test commonly is referred to as the "forced duction test," although more definitive information can be obtained, with less potential for injury to possibly compromised structures, if the examiner avoids undue force in manually rotating the eye.
The principal limitation of this diagnostic maneuver is the difficulty of performing it in the usual office setting. This is due at least in part to the failure of our commonly used topical anesthetic agents to eliminate completely the patient's appreciation of the forceps' grasp. Even when this is not especially painful, the sensation of the eye being touched often increases apprehension and provokes blepharospasm and tonic contraction of all of the extraocular muscles.
This