Objective To analyze the etiologies of severe vitreous hemorrhage in venerable age patients.Methods A retrospective series case study was adopted.Medical records of 30 cases 30 eyes severe vitreous hemorrhage venerable age patients were analyzed in Xuanwu Hospital Capital Medical University,Peking University Third Hospital and Beijing Tsinghua Chang Gung Hospital from July in 1999 to June in 2015.Visual acuity,intraocular pressure,anterior segment slit lamp microscopy,mydriasis funduscopy and ophthalmic B type ultrasound examination were used to evaluate 30 cases 30 eyes.Thirty eyes were all treated with pars plans vitrectomy (PPV).Results Mydriasis funduscopy examination showed that vitreous hemorrhage was so dense in 30 eyes that the fundus cannot be observed.The initial visual acuity examination showed that 8 eyes were count finger,5 eyes were hand move,16 eyes were light perception,and 1 eye was no light perception.There were dense light spots or clusters of high echoes in vitreous cavities,complete/incomplete posterior vitreous detachment (PVD) of all eyes;retinal detachment with different degrees in 5 eyes;proliferating cord adhesion to the wall of eyeball in 3 eyes.The etiologies included retinal vein occlusion (RVO) in 10 eyes (33.33％),retinal tear or retinal detachment in 7 eyes (23.33％),polypoidal choroidal vasculopathy (PCV) in 7 eyes (23.33％),proliferative diabetic retinopathy (PDR) in 4 eyes (13.33％).The above 4 etiologies were in 28 eyes,accounting for 93.33％.The others were ocular trauma in 2 eyes (6.67％).Conclusions The main cause to severe vitreous hemorrhage venerable age patients is RVO,followed by retinal tear or retinal detachment,PCV and PDR.Ocular trauma is rare.Vitrectomy is a diagnostic treatment,which can remove vitreous hemorrhage,improve the visual acuity of the patients,and determine the etiologies of the vitreous hemorrhage.

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