title: Studies on vitrectomy cases associated with complicated branch retinal vein occlusion.
abstract: OBJECTIVE
  To study the preoperative factors leading to vitrectomy, and to demonstrate the postoperative conditions causing the decreased visual acuity that results from branch retinal vein occlusion (BRVO).
  
  
  METHODS
  In 113 patients (114 eyes) with BRVO, the following data were analyzed: age, general complications, distribution of occluding vessels, location of retinal breaks, classification of vitreoretinal pathology, and the number of cases, period from onset of BRVO to vitreous hemorrhage and from vitreous hemorrhage to vitrectomy, number of operations, relationship between posterior vitreous detachment (PVD) and number of operations, preoperative photocoagulations, pre- and postoperative visual acuity, and cases with poor visual outcome.
  
  
  RESULTS
  The visual prognosis was much better in cases with vitreous hemorrhage only than in those with proliferative membrane and retinal detachment (P =.0023). Repeated surgeries were needed in the cases where there was only partial PVD (P =.0029). Macular disorders and optic nerve atrophy were the main causes of postoperative visual acuity < 0.1.
  
  
  CONCLUSIONS
  Early vitrectomy before development of vitreo retinal proliferation and retinal detachment, especially in cases where there is only partial PVD, seems to be essential for case management and treatment to attain better visual acuity for the patient.
authors.affiliation: Department of Ophthalmology, Juntendo University Urayasu Hospital, Chiba, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: H
authors.initials: H
authors.lastname: Ninomiya
authors.forename: Y
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Qiu
mesh_terms: D000368:Aged; D006801:Humans; D008875:Middle Aged; D012163:Retinal Detachment / Q000209:etiology / Q000601:surgery*; D012167:Retinal Perforations / Q000209:etiology / Q000601:surgery*; D012170:Retinal Vein Occlusion / Q000150:complications*; D014792:Visual Acuity; D014821:Vitrectomy; D020255:Vitreous Detachment / Q000209:etiology / Q000601:surgery*; D014823:Vitreous Hemorrhage / Q000209:etiology / Q000601:surgery*