FL-41 tint improves blink frequency, light sensitivity, and functional limitations in patients with benign essential blepharospasm.
OBJECTIVE
The objective of these 2 studies was to assess the efficacy of FL-41-tinted lenses in the treatment of benign essential blepharospasm (BEB).


METHODS
A randomized crossover study and a randomized crossover case-control study.


METHODS
The first study included 30 subjects with BEB. The second study included 26 subjects with BEB and 26 controls.


METHODS
For the first study, subjects were randomized to wear either FL-41 or gray-tinted lenses for 2 weeks. After a 2-week washout period, the other lens was worn for 2 weeks. Questionnaires were completed at baseline, after the first lens, and after the second lens. In the second study, surface electromyography (EMG) was used to measure blink frequency, duration, and force while subjects read and wore FL-41, rose, or gray-tinted lenses.


METHODS
Questionnaires were used to assess perceptions of light sensitivity and the effect of light sensitivity on activities of daily living (ADL). EMG was used to measure blink frequency, duration, and force.


RESULTS
Most participants observed improvement while wearing both FL-41 and gray-tinted lenses. FL-41-tinted lenses provided superior improvement in the areas of reading, fluorescent light sensitivity, overall light sensitivity, blepharospasm frequency, and blepharospasm severity. FL-41 lenses reduced mean blink rate compared with both rose and gray-tinted lenses, and reduced eyelid contraction force compared with rose-tinted lenses.


CONCLUSIONS
FL-41 lenses provided both subjective and objective benefit to subjects with BEB. Physicians should consider recommending this noninvasive and inexpensive lens tint to patients with BEB.


BACKGROUND
Proprietary or commercial disclosure may be found after the references.
Blackburn
Marcus K
MK
Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah Health Sciences Center, 65 Mario Capecchi Drive, Salt Lake City, UT 94132, USA.
Lamb
Randy D
RD
Digre
Kathleen B
KB
Smith
A Gordon
AG
Warner
Judith E A
JE
McClane
Robert W
RW
Nandedkar
Sanjeev D
SD
Langeberg
Wendy J
WJ
Holubkov
Richard
R
Katz
Bradley J
BJ
D000203:Activities of Daily Living; D000368:Aged; D001764:Blepharospasm / Q000503:physiopathology* / Q000628:therapy*; D001767:Blinking / Q000502:physiology*; D016022:Case-Control Studies; D018592:Cross-Over Studies; D004576:Electromyography; D005139:Eyeglasses; D005260:Female; D006801:Humans; D008297:Male; D020795:Photophobia / Q000503:physiopathology*; D011788:Quality of Life; D011795:Surveys and Questionnaires