Due to the development of the armamentarium and surgical techniques, the indications of pars plana vitrectomy (PPV) are expanding. It concerns also a relatively new indication, as is the branch retinal vein occlusion (BRVO) of the temporal part of the posterior pole of the retina with the secondary involvement of the macular region. The purpose of this prospective study is to demonstrate anatomical and functional results after the surgical decompression of the occlusion of the branch retinal vein draining the macular region. Since November 1999, 3 patients, one woman and 2 men (age 70, 47 and 76 years) with the quadrant BRVO of the temporal part of the retina involving the macular region were followed. The visual acuity before the surgery in all 3 patients was 6/36 (20/120 or 0.16) and the BRVO lasted for 3-5 months. The patients were examined by slitlamp biomicroscopy, and the course of the disease was documented by means of red-free fundus photographs as well as fluorescein angiograms. In all three patients, PPV and the adventitial sheathotomy of the arteriovenous crossing (AVC) were performed. Surgical decompression of BRVO and reperfusion of the ischemic part of the retina was achieved by separating the overlying arteriole from the venule at AVC. Neither per- nor postoperative complications were noted. In two patients, the visual acuity improved to 6/12 (20/40 or 0.5), and in the last one stabilized at 1/9 (20/180 or 0.11). The minimal follow-up period was 12 months. In conclusion, we recommend to performing this new type of delicate surgery procedure in individual cases on the basis of detailed biomicroscopial examination and fluorecein angiograms by an experienced vitreoretinal surgeon.