[Binocular vision in idiopathic macular foramen. Pre- and postoperative findings]

In recent years idiopathic macular hole has become an increasingly frequent indication for vitrectomy. To our knowledge, the literature contains no studies comparing binocular vision before and after vitrectomy. We therefore carried out a prospective study not only on visual acuity following vitrectomy but also, for the first time, on binocular vision. Stereopsis and fusion were evaluated in 37 patients with idiopathic macular holes (stage I-IV) using Bagolini striated glasses, the Titmus stereotest (contour stereopsis), the random dot test (global stereopsis), the Worth four-dot test and the phase-difference haploscope. The tests were performed preoperatively and 10-12 weeks after vitrectomy. Two patients with stage I macular hole showed no loss of stereopsis in conventional tests. One patient, however, exhibited suppression tendencies with partial exclusion. The 18 patients with stage II macular hole had a relative good visual acuity of 0.2-0.6, but subnormal binocular vision with marked suppression of foveal images. Postoperatively, the majority of these patients had symptom-free binocular vision and good stereopsis. Some, however, continued to experience foveal exclusion. Patients with macular hole stage III and IV (n = 17) had the poorest results. Although the postoperative visual acuity improved by 2 to 3 points in some patients (n = 6), in approximately one third it remained limited to global peripheral binocular vision. In summary, our findings show that even in early stages (I and II), macular hole can cause not only reduced visual acuity but also impairment or, in stage II, even loss of binocular vision. Vitrectomy in these early stages often leads to an overall improvement in visual acuity and binocular vision, whereas in more advanced stages vitrectomy often does not affect visual acuity and binocular vision. This should be taken into account when weighing up the indications for surgery.