Effects of augmented tenotomy and reattachment in the infantile nystagmus syndrome

Abstract

Purpose-To test the hypothesis that augmented tenotomy and reattachment surgery (AT-R), which involves placing an additional suture in each distal tendon during the 4-muscle tenotomy and reattachment (T-R) or other infantile nystagmus syndrome (INS) procedures, could increase the beneficial effects of many types of extraocular muscle (EOM) surgery to treat INS.Methods-Both infrared reflection and high-speed digital video systems were used to record the eye movements in 4 patients with INS before and after AT-R surgery. Data were analyzed using the eXpanded Nystagmus Acuity Function (NAFX) that is part of the OMtools software.Results-Placement of the augmentation suture did not interfere with Kestenbaum, Anderson, bilateral medial rectus muscle recession, or T-R surgeries. The therapeutic effects of AT-R were similar to but not equal to those from the traditional single-suture surgeries (ie, broadening longest foveation domain [LFD] but no improvement of NAFX peak). The average of the NAFX percent improvements after AT-R was within 31% of those estimated from NAFX values before T-R; the average of the percent broadenings of the LFD values after AT-R was within 16%.Conclusions-The AT-R does not improve the foveation quality in INS above the traditional T-R surgery. It is not improved by an additional suture; indeed, some improvements may be diminished by the added suture. The hypothesized augmented-tendon suture technique (sans tenotomy) has been modified and remains to be tested.

Longitudinal Evaluation of Eye Misalignment and Eye Movements Following Surgical Correction of Strabismus in Monkeys

“…8 We measured fixation stability in these animals at the different time points and found a temporary improvement in fixation stability of the treated eye when the untreated eye was viewing but no consistent changes when the treated eye was viewing. Dell'Osso et al suggested that tenotomy surgery reduces nystagmus intensity 47,48 in humans with infantile nystagmus syndrome due to manipulation of proprioceptive receptors in the EOM. It is possible that similar mechanisms are at play following the strabismus correction surgery that we performed, although another study that attempted tenotomy surgery in monkeys with infantile nystagmus showed inconsistent results.…”