title: Acute retinal necrosis: factors associated with anatomic and visual outcomes.
abstract: OBJECTIVE
  To examine the factors associated with anatomic and visual outcomes in Japanese patients with acute retinal necrosis (ARN).
  
  
  METHODS
  One hundred four patients with ARN who were followed for more than 1 year at nine referral centers were reviewed. Retinal involvement at initial presentation was classified into four groups: zone 1 (posterior pole, n = 22), zone 2 (midperiphery, n = 54), zone 3 (periphery, n = 25), and unknown (n = 3). Forty-eight eyes underwent prophylactic vitrectomy before development of retinal detachment (vitrectomy group); 56 eyes were treated conventionally without prophylactic vitrectomy (observation group).
  
  
  RESULTS
  The retina was attached in 28 of 48 eyes (58.3 %) in the vitrectomy group and 42 of 56 eyes (75.0 %) in the observation group at the final visit (P = 0.071). At 1 year, 56 eyes (53.8 %) had a best-corrected visual acuity (BCVA) of 20/200 or worse. Multivariate logistic regression analyses identified zone 1 disease (odds ratio = 4.983) and optic nerve involvement (odds ratio = 5.084) as significantly associated with BCVA of 20/200 or worse. Among the zone 3 eyes, significantly (P = 0.012) more eyes in the observation group than in the vitrectomy group had an attached retina.
  
  
  CONCLUSIONS
  Prophylactic vitrectomy did not improve the final BCVA in any eyes. Zone 3 eyes had better outcomes without prophylactic vitrectomy.
authors.affiliation: Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Chiharu
authors.initials: C
authors.lastname: Iwahashi-Shima
authors.forename: Atsushi
authors.initials: A
authors.lastname: Azumi
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Ohguro
authors.forename: Annabelle A
authors.initials: AA
authors.lastname: Okada
authors.forename: Toshikatsu
authors.initials: T
authors.lastname: Kaburaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Goto
authors.forename: Koh-Hei
authors.initials: KH
authors.lastname: Sonoda
authors.forename: Kenichi
authors.initials: K
authors.lastname: Namba
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Mizuki
authors.forename: Manabu
authors.initials: M
authors.lastname: Mochizuki
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000473:pathology*; D012163:Retinal Detachment / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D015882:Retinal Necrosis Syndrome, Acute / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome; D014792:Visual Acuity; D014821:Vitrectomy; D055815:Young Adult