The results of modified hang back surgery in the treatment of infantile esotropia

In our study, the files of 120 patient were followed with the diagnosis infantile esotopia and treated bimedial rectus muscle recession using modified Hang Back technique were reviwed retrospectively. Cases were evaluated by the time of surgery, coexistance with inferior oblique muscle weakening surgery and presence of refractive error. When classified according to the time of surgery, early surgery was performed in 80 (67%) patients and late surgery was performed in 40 (33.3%) patients. There were 40 cases (33.3%) who underwent surgery with inferior oblique muscle weakening procedure, and 80 cases (66.7%) undergoing bimedial recession surgery alone. The presence of refractive error was observed in 27 (22.5%) and not in 93 (77.5%) cases. Cases with esotropia or exotropia up to 10 postoperatively were considered successful. More than 10 esotropia were considered to be undercorrected and more than 10 exotropia were evaluated as overcorrected. At the end of the first year, nine patients (7.5%) had more than 10PD esotropia. Their mean values were 21PD (16-35PD), and these patients had large angle of deviation preoperatively. Twenty-four patients (20%) had small angle (10PD and less) esotropia. Only one patient (0.83%) had overcorrected. According to these results, our success rate is 91.6% and it is higher than the rates reported in similar studies in the literature. When the cases were divided into subgroups which were the time of surgery, operation performed with inferior oblique weakening surgery and presence of refractive error, the difference between preoperative angle of deviation and postoperative 1st month, 6th month and 1st year agle of deviation was statistically significant in all three groups (p <0.001). When double regression analysis was performed, it was found statistically significant that early surgery and refractive error were effective in the success of surgical treatment (p:0,037, p:0,039). In conclusion, in our study, one of the surgical treatment options of infantile esotropia, medial rectus recession procedure was performed with modified Hang Back technique. The aim of this novel technique is to prevent unwanted movement of the muscle in the horizontal and vertical axis seen in the classical Hang Back technique. In our technique, after measuring the amount of regression, the suture vertically placed on the sclera is used to prevent movement of the muscle up or down and the suture placed on the anterior face of the muscle is aimed to prevent movement on the horizontal axis. The difference between the preoperative and postoperative angle of deviation determined in the patients was statistically significant. In addition, over and undercorrection and the development of alphabetic pattern shift were less common in our modified technique.