NEW APPROACH IN STRABISMUS SURGERY IN HIGH MYOPIA

Aims-To develop appropriate methods of eye muscle surgery in highly my opic patients with esotropia and hypotropia, with respect to the patho logical findings in high resolution magnetic resonance imaging (MRT). Methods-35 patients with unilateral or bilateral high myopia and strab ismus-that is, axial length of the globe averaged 29.4 mm. hluItiple c oronal, transverse, and parasagittal MRI image planes were obtained us ing a Siemens Magnetom 1.5 tesla MRI scanner. In 15 patients with a pa thological plane of recti extraocular muscles found by MRI and confirm ed intraoperatively, a new technique of eye muscle surgery was perform ed to reestablish the physiological muscle plane. This was checked pos toperatively in addition to the measurement of alignment and motility by MRI. Results-The new MRI finding of a dislocation of the lateral re ctus (LR) into the temporocaudal quadrant by 3.4 mm requires new surgi cal techniques. Only fixing the LR in the physiological meridian at th e equator with a silicone loop ('guide pulley') or a non-absorbable su ture is a causal therapy. This yields alignment and improves abduction and elevation. Conclusions-If the described misalignment of the LR is detected by MRI, a common high dosage recess-resect procedure for eso tropia may even aggravate the deviation. The most important aim of eye muscle surgery is to normalise the pathological path of the LR. The r estoration of the physiological function of the dislocated LR is remar kable.