McNeer et al in their article titled "Botulinum Toxin Management of Essential Infantile Esotropia in Children" (Arch Ophthalmol. 1997;115:1411-1417) reported their extensive experience with this modality of treatment.
In a previous independent best-case study of patients who actually achieved alignment for a minimum of 6 months (during the first 2 years of life) after botulinum injections into the medial recti, I found a direct relationship between the quantity of the initial deviation with the number of injections required to achieve alignment.1 In general, patients with 40 prism diopters (PD) or more of esotropia required 3 or more medial recti injections to achieve alignment. I am wondering if the authors also found a similar correlation of the quantity of the initial deviation with the number of injections necessary to align the patient. Which leads me to the next point: The authors report a mean initial deviation of only 33 PD which is significantly smaller than the mean initial deviation of 55 PD reported in several larger groups that were treated surgically.2,3 Indeed, this observation was also made in Kushner's editorial in the same journal issue (Arch Ophthalmol. 1997;115:1458-59.) The question arises, therefore: Is the authors' series representative of the typical essential infantile esotropia group of patients?
Ing MR. Botulinum Toxin Treatment of Infantile Esotropia in Children. Arch Ophthalmol. 1998;116(6):833. doi: