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AIM: To compare outcomes of conventional and Hang-back methods of inferior oblique (IO) recession in V-pattern strabismus with inferior oblique overaction (IOOA). METHODS: Comparative randomized study was conducted consisting of 50 patients, age 6 to 35y having V-pattern strabismus [>15 prism diopter (PD)] with IOOA. They were divided equally in two groups and underwent IO recession, group A by conventional method and group B by Hang-back method. Parameters evaluated were reduction in V-pattern and IOOA, shift in torsion, improvement in binocular status. Success was a residual V-pattern of less than 10 PD at 1y of follow up. RESULTS: The mean V-pattern preoperatively and postoperatively at 1y was 24±5.4 PD and 4.2±3.51 PD in group A and 23.44±6.44 PD and 5.76±3.8 PD in group B respectively. The mean reduction in V-pattern was 20±6.78 PD in group A and 18.2±5.48 PD in group B. The mean correction of IOOA was 18.48±3.13 PD in group A and 16±2.93 PD in group B. Mean shift in extorsion was 3.08±1.8 degree in group A and 3.72±2.14 degree in group B. CONCLUSION: Both the procedures achieve a significant and comparable reduction in V-pattern and IOOA. Hang-back recession being a landmark free surgery eliminates the need for intrascleral suturing thereby reducing the risk of scleral perforation with possible postoperative adjustment of muscle. It may be considered as a good alternative for IO recession in patients of V-pattern strabismus with mild to moderate amount of IOOA.

We compared the results of strabismus surgery using adjustable and non-adjustable hang-back muscle recessions in 38 patients having concomitant exotropia. The two groups were matched for age of the patient, type of concomitant exotropia, amount of deviation, and type and amount of muscle surgery. At 6 months follow-up, 18 of the 19 patients (95%) in the adjustable hang-back recession group and 17 of the 19 patients (90%) in the non-adjustable hang-back recession group had ocular alignment within 10 prism diopters (PD) of orthophoria. At the most recent follow-up (mean 3.4 years), 12 of the 13 patients (92%) in adjustable hang-back recession group and 12 of the 14 patients (86%) in non-adjustable hang-back recession group had ocular alignment within 10 PD of orthophoria. There was no statistically significant difference in success rates between the two groups at 6 months postoperatively and at the most recent follow-up. This preliminary study suggests that non-adjustable hang-back muscle recession can be considered for routine concomitant exotropia.

Background: The Y-splitting procedure has been used both to treat up-shoots and down-shoots in Duane syndrome, and as a substitute for posterior fixation suture. The Y-split is often performed in conjunction with a hang-back recession when a large amount of recession or an adjustable suture is necessary. Herein, we evaluated the stability of Y-splitting hang-back recession in the rectus muscle. Methods: Under general anesthesia, a 5-mm hang-back recession of the superior rectus muscle (SR) with Y-splitting was performed in ten eyes from ten rabbits (hang-back group). A conventional recession was performed in the SR of the fellow eye (control group). Six weeks after the procedure, the distance between the original insertion and the recessed SR (recession amount) and the width between the nasal and temporal halves of the SR were measured. These values were compared to the measurements taken at the time of surgery. Results: The hang-back group had a significantly larger forward displacement than the control group ( P < 0.001 for both the nasal and temporal halves). The width change between the nasal and temporal halves was also significantly larger in the hang-back group (4.94 ± 1.32 mm) than in the control group (1.14 ± 0.60 mm, P < 0.001). Additionally, the Y-configuration appeared to be more collapsed in the hang-back group than in the control group. Conclusion: Y-splitting of the rectus muscle may be unstable when it is combined with a hang-back recession. Surgeons should consider this possibility when performing Y-splitting procedures. [ABSTRACT FROM AUTHOR]

Background: Hang-back recession and botulinum toxin injection are performed as one treatment option for the correction of large angles of deviation. However, the effect of botulinum toxin on hang-back recession has not been thoroughly evaluated. The purpose of this study is to investigate the effect of botulinum toxin on the hang-back recession of extraocular muscles. Methods: Under general anesthesia, 6-mm hang-back recession of the superior rectus muscle (SR) was performed in all eyes of 12 rabbits. Botulinum toxin (5 IU, 0.1 ml) was injected into the SR of one eye in each rabbit. The inferior rectus muscles (IR) of both eyes were excised to model severe paralysis. The distance between the superior limbus and the new insertion was measured immediately after the procedure and 3 months postoperatively. Changes in the location of the insertion were evaluated and compared between both eyes. Results: After excision of the IR, upward deviation was observed in all eyes. The insertion site of the recessed SR immediately after the procedure and 3 months postoperatively were significantly different in all rabbit eyes with or without botulinum injection ( P = 0.002, 0.002); SR advancement was observed in both cases. The amount of advancement was 1.38 ± 0.41 mm in the SR without botulinum toxin injection and 2.29 ± 0.45 mm in the SR with injection; this difference was statistically significant ( P = 0.002). Conclusions: Botulinum toxin injection reduced the amount of hang-back recession in deviated rabbit eyes. Surgeons should be aware that botulinum toxin can diminish the effects of hang-back recession when used simultaneously. [ABSTRACT FROM AUTHOR]

This communication reports the histological structure of loop recessions of extraocular muscles from seven patients. In all cases the loops formed pseudotendons in which the typical histological structure was well established by four months. Subsequently, moulding of these pseudotendons occurred with improved alignment of collagen and decrease in vascularity. By three and a half years after the operation the pseudotendon had acquired a very close resemblance to true tendon. [ABSTRACT FROM AUTHOR]

Aim: To compare outcomes of conventional and Hang-back methods of inferior oblique (IO) recession in V-pattern strabismus with inferior oblique overaction (IOOA)., Methods: Comparative randomized study was conducted consisting of 50 patients, age 6 to 35y having V-pattern strabismus [>15 prism diopter (PD)] with IOOA. They were divided equally in two groups and underwent IO recession, group A by conventional method and group B by Hang-back method. Parameters evaluated were reduction in V-pattern and IOOA, shift in torsion, improvement in binocular status. Success was a residual V-pattern of less than 10 PD at 1y of follow up., Results: The mean V-pattern preoperatively and postoperatively at 1y was 24±5.4 PD and 4.2±3.51 PD in group A and 23.44±6.44 PD and 5.76±3.8 PD in group B respectively. The mean reduction in V-pattern was 20±6.78 PD in group A and 18.2±5.48 PD in group B. The mean correction of IOOA was 18.48±3.13 PD in group A and 16±2.93 PD in group B. Mean shift in extorsion was 3.08±1.8 degree in group A and 3.72±2.14 degree in group B., Conclusion: Both the procedures achieve a significant and comparable reduction in V-pattern and IOOA. Hang-back recession being a landmark free surgery eliminates the need for intrascleral suturing thereby reducing the risk of scleral perforation with possible postoperative adjustment of muscle. It may be considered as a good alternative for IO recession in patients of V-pattern strabismus with mild to moderate amount of IOOA., (International Journal of Ophthalmology Press.)

Purpose: To compare adjustable sutures versus nonadjustable sutures for intermittent exotropia., Methods: In this randomized prospective interventional study, 40 adult patients with intermittent exotropia were randomly divided into 2 equal groups. Both groups underwent bilateral lateral rectus recession. In group A, adjustable suture recession was performed, and in group B, nonadjustable suture recession was performed. Patients were followed up for 6 months and outcome measures were residual deviation, binocular status, and need for resurgery., Results: Success was defined as alignment of 2 eyes <10 prism diopters (PD) of deviation at the end of 12 weeks. Need for resurgery in a 12-week follow-up period was considered to be failure. At the end of the study, 90% of the patients in group A and 85% of the patients were within 10 prism diopters of orthophoria (p = 0.316). At the end of 6 months, mean deviation in group A was 6.20 PD and in group B it was 5.60 PD (p = 0.31). No patient underwent resurgery., Conclusions: Adjustable hang-back recession has no definite added advantage over nonadjustable hang-back recession in intermittent exotropia.