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Effectiveness of 0.3% Hyaluronic Acid Eye Drops for Benign Essential Blepharospasm and Hemifacial Spasm with
Anuchit Poonyathalang1, Nanida Tiraset1, Natthapon Rattanathamsakul1
1From the Department of Ophthalmology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Background:
This study evaluates the effectiveness of 0.3% hyaluronic acid (HA) eye drops in patients receiving concurrent botulinum toxin (BoNT) injections for benign essential blepharospasm (BEB) or hemifacial spasm (HFS).
Methods:
This randomized controlled cross-over trial study involved 14 patients with BEB and 33 patients with HFS randomized into two groups (early treatment and deferred treatment) for 3 months of treatment with 0.3% HA eye drops. Data collected at baseline, 3 months, and 6 months included Blepharospasm Severity Scale (BSS) score in patients with BEB; Samsung Medical Class Grading Scale score in patients with HFS; and dry eye symptoms, lower eyelid tear meniscus height (TMH), tear breakup time (TBUT), and corneal fluorescein staining in both groups.
Results:
After 3 months of 0.3% HA instillation, patients with BEB in both groups showed significant improvement in BSS, TMH, TBUT, and the amelioration of subjective dry eye symptoms and corneal staining (P < 0.05). However, discontinuation of 0.3% HA eye drops worsened BSS, TMH, and TBUT. Patients with HFS also experienced significant improvement in Samsung Medical Class score, subjective dry eye symptoms, and objective corneal findings (P < 0.05).
Conclusions:
Treatment with 0.3% HA eye drops led to significant improvement in spasm severity, and dry eye parameters, after 3 months of instillation in patients with BEB or HFS during concurrent treatment with BoNT injections. The 0.3% HA eye drops were safe and might serve as an add-on treatment for symptom improvement.
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