Early retreatment of infantile esotropia: comparison of reoperation and botulinum toxin. Results of a prospective randomized trial of botulinum toxin therapy in acute unilateral sixth nerve palsy. Retreatment of children after surgery for acquired esotropia: reoperation versus botulinum injection. Botulinum vs adjustable suture surgery in the treatment of horizontal misalignment in adult patients lacking fusion.
To compare the efficacy of reoperation and botulinum toxin injection in treating infantile esotropes early after unsatisfactory surgical alignment.
                55 strabismic children who had been unsuccessfully operated for infantile esotropia were randomised to reoperation (28 patients) or botulinum toxin injection (27 patients). The motor outcomes (percentage of successful motor outcome and percentage change in deviation) were compared at 6 months, 1 year, and 3 years after retreatment, and the sensory outcomes (percentage with fusion ability and stereo perception) at the 3 year follow up visit.
                The motor and sensory outcomes and the stability of motor results were similar in patients reoperated and treated with botulinum injection. At the 3 year visit 67.8% and 59.2% of children were, respectively, within 8 prism dioptres of orthotropia (p=0.72). The frequency of fusion ability was, respectively, 60.7% and 51.8% (p=0.71), and the frequency of stereo perception (</=400 seconds of arc, Randot circles), 57.1% and 48.1% (p=0.70). The botulinum injection was more likely to be effective when carried out in the 6 months following initial surgery.
                Botulinum injection is a rapid and less invasive alternative to reoperation in children who have been unsuccessfully treated with surgery to correct infantile esotropia. Forty-seven patients entered a prospective randomized trial to assess the effect of early botulinum neurotoxin A treatment to the ipsilateral antagonist medial rectus on the ultimate recovery rate of acute unilateral sixth nerve palsy. Twenty-two patients received injections and 25 acted as controls. The overall etiologies were microvascular (72.3%), unknown (17%), multiple sclerosis (6%), and one case each of central nervous system (CNS) sarcoidosis and basilar artery ectasia. Eighty-three percent of the patients entered the trial within 2 weeks of the onset of symptoms and 95.7% within 3 weeks. The controls had a final recovery rate of 20/25 (80%), and the injected group had a final recovery rate of 19/22 (86%). No serious side effects were encountered. We conclude that there is no evidence for a prophylactic effect of botulinum toxin in the group that we have studied. Two viable options were compared, reoperation and botulinum toxin injection, in the management of children who need retreatment after surgery for acquired esotropia.
                47 strabismic children previously operated to correct an acquired esotropia were randomised to reoperation or botulinum toxin injection. Reoperation was undertaken in 24 of these patients and botulinum toxin injection in 23 of them. The percentage net change in distance deviation, the percentage of patients with successful motor outcome, detectable fusion, and stereopsis were compared 1 year after retreatment and at last visit (average follow up: 2.9 years in reoperation group, and 2.7 years in botulinum group). The motor success rate relative to time elapsed from initial surgery was evaluated.
                There was no significant difference in the motor and sensory outcomes between patients reoperated and treated with botulinum injection. The frequency of correction to within 8 prism dioptres of orthotropia was, respectively: 75% versus 69.56% at 1 year; 70.83% versus 60.86% at last visit. Botulinum injection could be more effective when performed within 3 months of initial surgery.
                Botulinum injection is a rapid and safe procedure that may be as effective as reoperation in the management of children who need a secondary procedure after surgery for acquired esotropia. Thirty patients were treated with either botulinum toxin or adjustable suture surgery in a prospective, randomized clinical trial. All patients had horizontal deviations greater than 10 prism diopters and absent fusion. Seventeen patients were assigned to toxin treatment, and 13 were assigned to surgical treatment. Follow-up at 6 months after either procedure indicated that surgery was superior, with patient alignment showing a 92.7% average net change, compared with a 50.50% net change in the botulinum-treated group. There was no difference in response between those patients with a starting deviation of 20 PD or less and greater than 20 PD in the surgery group. However, in the botulinum-treated group, those patients with a starting deviation of 20 PD or less seemed to show better responses than those patients with greater than 20 PD. Patients with esotropia showed an 88.89% change with surgery and a 51.55% change with toxin treatment. Patients with exotropia had a 95.83% change with surgery but a 50.3% change with toxin treatment. Since we had 20 patients with exotropia and 10 patients with esotropia, a more formal comparison would require larger numbers.
The majority of published literature on the use of botulinum toxin in the treatment of strabismus consists of retrospective studies, cohort studies or case reviews. Although these provide useful descriptive information, clarification is required as to the effective use of botulinum toxin as an independent treatment modality. Four RCTs on the therapeutic use of botulinum toxin in strabismus have shown varying responses ranging from a lack of evidence for prophylactic effect of botulinum toxin in acute sixth nerve palsy, to poor response in patients with horizontal strabismus without binocular vision, to no difference in response in patients that required retreatment for acquired esotropia or infantile esotropia. It was not possible to establish dose effect information. Complication rates for use of Botox™ or Dysport™ ranged from 24% to 55.54%.