title: Visual outcomes in treated bacterial keratitis: four years of prospective follow-up.
abstract: OBJECTIVE
  We described the change in visual acuity experienced by eyes successfully treated for bacterial keratitis.
  
  
  METHODS
  This was a prospective cohort study of a subset of study participants who had previously enrolled in the Steroids for Corneal Ulcers Trial (SCUT). All study participants had been diagnosed with culture-proven bacterial keratitis before enrollment in SCUT and subsequently were randomized to adjunctive topical corticosteroids or placebo. During SCUT, we monitored study participants at enrollment, 3 weeks, 3 months, and 12 months. We invited a subset to complete a comprehensive eye examination approximately 4 years after enrollment in SCUT. Certified refractionists assessed best spectacle-corrected visual acuity (BSCVA) using the same protocol at each study visit.
  
  
  RESULTS
  We examined 50 SCUT participants at 4 years after enrollment. Among those in this cohort, mean logMAR BSCVA at enrollment was 0.85 (Snellen equivalent, 20/160; 95% confidence interval [CI], 0.71-0.99). On average, visual acuity improved by 2.9 logMAR lines from enrollment to 3 weeks (P < 0.001), 1.2 lines from 3 weeks to 3 months (P = 0.002), and 0.8 lines from 3 to 12 months (P = 0.01). The BSCVA did not change significantly between 12 months and 4 years (0.04-line improvement, P = 0.88). After controlling for visual acuity at enrollment, BSCVA was not significantly different between the corticosteroid and placebo groups at 4 years (P = 0.53).
  
  
  CONCLUSIONS
  Cases of bacterial keratitis may continue to demonstrate improvements in visual acuity up to 12 months following diagnosis, but further improvements are unlikely. These findings may guide the appropriate timing of surgical intervention in these patients. (ClinicalTrials.gov number, NCT00324168.).
authors.affiliation: Department of Ophthalmology, University of California, San Francisco, San Francisco, California, United States.
authors.forename: Scott M
authors.initials: SM
authors.lastname: McClintic
authors.forename: Namperumalsamy V
authors.initials: NV
authors.lastname: Prajna
authors.forename: Muthiah
authors.initials: M
authors.lastname: Srinivasan
authors.forename: Jeena
authors.initials: J
authors.lastname: Mascarenhas
authors.forename: Prajna
authors.initials: P
authors.lastname: Lalitha
authors.forename: Revathi
authors.initials: R
authors.lastname: Rajaraman
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Oldenburg
authors.forename: Kieran S
authors.initials: KS
authors.lastname: O'Brien
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Ray
authors.forename: Nisha R
authors.initials: NR
authors.lastname: Acharya
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Lietman
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Keenan
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001372:Aza Compounds / Q000627:therapeutic use; D003320:Corneal Ulcer / Q000188:drug therapy* / Q000503:physiopathology; D004311:Double-Blind Method; D015818:Eye Infections, Bacterial / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D024841:Fluoroquinolones; D005500:Follow-Up Studies; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077266:Moxifloxacin; D011239:Prednisolone / Q000031:analogs & derivatives* / Q000627:therapeutic use; D011446:Prospective Studies; D011804:Quinolines / Q000627:therapeutic use; D012044:Regression Analysis; D014792:Visual Acuity / Q000187:drug effects / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D001372:Aza Compounds; D024841:Fluoroquinolones; D005938:Glucocorticoids; D011804:Quinolines; C009022:prednisolone phosphate; D011239:Prednisolone; D000077266:Moxifloxacin
keywords: clinical trial; keratitis; long-term; outcomes; prospective; visual acuity