title: Posterior vitreous detachment: clinical correlations.
abstract: BACKGROUND
  To evaluate the frequency of, and the factors which are primarily and secondarily associated with, posterior vitreous detachment (PVD), and to correlate the presence of PVD with various demographic and ophthalmic entities.
  
  
  METHODS
  The clinical prospective observational cohort study included 1,481 subjects (740 women, 741 men) with a mean age of 63.45 +/- 14.97 years (mean +/- SD; range, 10.3-94.9 years) and a mean spherical equivalent refractive error of +0.68 +/- 2.13 dpt (range, -14.25 to +13.50 dpt). The presence of PVD was assessed by indirect and direct ophthalmoscopy, fundus biomicroscopy and by using a Hruby lens upon pharmacologically dilated pupil. Main outcome measures were frequency of PVD, association with age, refractive error, cataract surgery, diabetes mellitus, arterial hypertension, history of ocular trauma, vitreous hemorrhage, various retinal disorders, nonarteritic anterior ischemic optic neuropathy (AION) and open-angle glaucoma.
  
  
  RESULTS
  The occurrence of PVD was significantly correlated with increasing age (p < 0.001), myopic refractive error (p < 0.001), female gender (p < 0.001), and surgical aphakia (p < 0.001). PVD occurred significantly more often bilaterally than unilaterally (p < 0.001). Patients with unilateral PVD were significantly (p < 0.001) younger than the patients with bilateral PVD. PVD was seen significantly (p = 0.038) less frequently in AION than in the remaining study population. The frequency of PVD was lower in eyes with than without diabetic retinopathy (p = 0.095), optic disc neovascularization (p = 0.07) and retinal neovascularization (p = 0.09). There was no significant association between the presence of PVD and macular hole, macular edema, retinal vascular occlusive disorders, age-related macular degeneration and open-angle glaucoma.
  
  
  CONCLUSIONS
  These data of a large prospective study of PVD confirm some of the findings of previous smaller and retrospective studies. They also provide new information which may be helpful for the understanding of the pathophysiology of PVD and the role of PVD in the pathogenesis of various retinal and optic disc lesions.
authors.affiliation: Department of Ophthalmology, College of Medicine, University of Iowa, Iowa City, Iowa, USA. sohan-hayreh@uiowa.edu
authors.forename: Sohan Singh
authors.initials: SS
authors.lastname: Hayreh
authors.forename: Jost B
authors.initials: JB
authors.lastname: Jonas
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001036:Aphakia, Postcataract / Q000150:complications; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009887:Ophthalmoscopy; D011446:Prospective Studies; D012030:Refractive Errors / Q000150:complications; D012307:Risk Factors; D012737:Sex Factors; D020255:Vitreous Detachment / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology