Periosteal Muscle Anchoring for Large Angle Incomitant Squint
Gillian G. Adams; Sarah Hull; Tarang Gupta; David H. Verity
Moorfields Eye Hospital
Introduction: To describe the evolution of a modified surgical technique for correcting large angle incomitant exodeviations. This study expands on a previous report of 7 patients.1
Methods: A consecutive series of 27 patients with predominantly third nerve palsy (n=21, medial rectus palsy=2, exotropia=2, Moebius=1, CPEO=1) were operated on between 2005-2017 by a joint Strabismus/Adnexal team. All patients had minimal medial rectus function and 15 patients had undergone prior surgery. Retrospective analysis included prism dioptre (PD) deviations and complications.
Results: Four patients were excluded for lack of follow up. Pre operative exotropia ranged from 45 to >115 PD base in. There were 30 operations (19 patients one operation, 4 patients >1) with the medial rectus insertion anchored to periosteum via a retrocaruncular approach.2 The lateral rectus was disinserted then fixated to the lateral orbital rim except for 2 recessions and 5 botulinum toxin injections (4 performed 2005-6). Medial traction sutures were inserted in 23 of 30 surgeries (the 7 without performed 2005-6) for a mean of 5 weeks (range 2-8). Final review was at an average 26 months (range 2 to 130) with deviations ranging from 80 PD base in to 14 PD base out and a mean reduction of 42 PD (range 10 to 79). There were no complications.
Discussion: Large angle incomitant exodeviations present a difficult surgical challenge. The surgical approach has evolved with lateral rectus disinsertion now preferred and traction sutures routinely inserted.
Conclusion: We advocate a combined bi-rectus fixation approach with traction sutures to hold the globe in the primary position.
References: 1 Hull S, Verity DH, Adams GG. Periosteal muscle anchoring for large angle incomitant squint. Orbit. 2012 Feb;31(1):1-6
2 Saxena R, Sinha A, Sharma P, Phuljhele S, Menon V. Precaruncular approach for medial orbital wall periosteal anchoring of the globe in oculomotor nerve palsy. J AAPOS. 2009 Dec;13(6):578-82