Purpose
Traumatic brain injury is associated with paroxysmal sympathetic hyperactivity (PSH), storms of excess sympathetic nervous system tone. While severe PSH is treated in inpatients with morphine and beta blockers, subtler forms of PSH may persist affecting the rehabilitation of post-concussion syndrome(PCS). Exaggerated sympathetic tone to the near reflex in PCS reduces effectiveness of the near response. Increased effort necessary to oppose this results in spasm of the near reflex. Asthenopia results reducing effectiveness and prolonging the duration of rehabilitation reliant upon eye movements and near therapies. Small studies have reported the use of atropine and cyclopentolate in post traumatic spasm of the near reflex. After routine dilated fundus examination of PCS patients with tropicamide 1% ophthalmic solution, a pattern of reduction in asthenopic symptoms on eye movements and convergence was noted. Can tropicamide 1% ophthalmic solution, a shorter acting cycloplegic with minimal side effects, be used as an adjunct treatment for post concussive visual and ocular motor symptoms?
Methods
A retrospective chart review was performed. Inclusion criteria: 1)post-concussion patients with a comprehensive vision evaluation 2)clinical findings of accommodative, ocular motor and convergence anomalies 3)symptoms of asthenopia on saccades, pursuits, gaze holding and convergence 4)subjective recordings of 0-10 on an aversion scale for right, left, up, down gaze and convergence 5)routine dilation with one drop 1% tropicamide in each eye 6)post dilation repeat of aversion scores with full near plus. N=14 patient records met these criteria.
Results
Significant reduction in symptoms was reported by subjects in at least one or more positions of gaze. Highest individual reduction from pre-T1% to post-T1% discomfort on an aversion scale was (10)for convergence (7)up-gaze (6)right-gaze and (7)left-gaze. The average percentage reduction in aversion scores were for convergence (42.14%) up gaze (26.42%) right gaze (30.71%) and left gaze (34.28%).
Conclusions
Tropicamide 1% ophthalmic solution provides significant symptom relief for post-concussion asthenopia related to ocular motility and convergence. Future studies will evaluate the efficacy of tropicamide 1% as an adjunct treatment for rehabilitation therapies.
Keywords: 522 eye movements •
611 neuro-ophthalmology: cortical function/rehabilitation •
751 vergence