Long-term follow-up of patients with frontalis sling operation in the treatment of essential blepharospasm unresponsive to botulinum toxin therapy

Objective Botulinum toxin is the treatment of choice in patients with essential blepharospasm, but about 4% of patients show no sufficient effect. Many of these patients try to open their eyes by innervating their frontalis muscle. This led to the idea of performing frontalis suspension, normally used for certain types of ptosis. We set out to evaluate the long-term results, complication rates and patient acceptance of this intervention. Methods Frontalis sling operation was carried out on 252 eyes of 132 blepharospasm patients between 1992 and 2004. In all patients botulinum toxin treatment was administered before surgery with no or only brief and incomplete effect even with increasing toxin doses. In 120 patients surgery was performed under local anaesthesia, while 12 patients were operated upon under general anaesthesia ( mostly bilateral). Silk sutures were employed in the first 14 eyes, and in all others we used Gore-Tex suture material. Results The duration of follow-up was 3-154 months; 60 patients were followed up for at least 5 years. Seventy-three per cent of patients reported an improvement after surgery. Long-term subjective improvement showed a median of 50% on a scale ranging from 0%=no improvement to 100%=no complaints. No serious corneal complications occurred, although slight overcorrection is desirable in the first days after surgery for a satisfactory long-term result. Seven per cent of operations had to be revised due to suture granulomas or extruded suture material. The effect of surgery generally remained stable over the years, with most patients needing additional treatment with botulinum toxin. In cases of decreasing effect (5% of eyes), the sutures were tightened under local anaesthesia. Conclusion Frontalis suspension can be considered as a minimally invasive but very effective and even reversible procedure in "poor responders" to botulinum toxin, with good long-term effect and good acceptance by the patients. Additional treatment with botulinum toxin is required in most patients in order to increase the desirable imbalance between the frontalis and the orbicularis muscle.