Risk factors for glaucoma filtering bleb infections.

OBJECTIVE: To determine risk factors for bleb-related ocular infection after glaucoma filtering surgery. METHODS: A case-control study comparing all consecutive cases of glaucoma filtering bleb-related infections (55 eyes of 55 patients) with matched control eyes between January 1, 1990, and June 30, 1998, was performed. Bleb-related infection was classified as blebitis when a mucopurulent infiltrate was identified within the bleb and associated with mild to moderate anterior segment inflammation. Eyes with endophthalmitis had hypopyon, cells in the anterior vitreous cavity, or a positive vitreous biopsy sampling result. A control was selected for each case based on matching of the surgeon, date and type of glaucoma surgery, and type of antifibrotic agent used. Multivariate, matched, case-control logistic regression analysis was performed using age, race, sex, diagnosis, number of previous incisional operations, filtering bleb location, and presence of bleb leak to determine which variables were associated with bleb-related infection. RESULTS: The odds of an eye with a bleb-related infection being seen with a concomitant late-onset bleb leak are 25.8 times the odds of a noninfected eye having a late-onset bleb leak at any time in the postoperative period (P<.001; 95% confidence interval, 2.3-294.1). Other risk factors for bleb-related infection included younger age (P = .05), black race (P = .03), diagnosis of primary open-angle glaucoma (P = .03), and inferior location of the filtering bleb (P = .04). CONCLUSIONS: Late-onset bleb leakage is a significant risk factor for bleb-related infection. The risk of infection may warrant closure of late-onset bleb leaks in selected eyes.

Noninfectious crystalline keratopathy after postoperative subconjunctival 5-fluorouracil.

PURPOSE: To describe a case of transient, noninfectious crystalline keratopathy after postoperative subconjunctival 5-fluorouracil. METHOD: Case report. Slit-lamp biomicroscopic examinations were performed during serial office examinations. RESULTS: A 69-year-old woman underwent an uncomplicated trabeculectomy with adjunctive sponge 5-fluorouracil application for 5 minutes in her left eye. Postoperative treatment included topical prednisolone acetate, ciprofloxacin, and scopolamine. She was initially examined with intrastromal corneal crystalline deposits 5 days after her first postoperative subconjunctival injection of 5-fluorouracil. The deposits completely disappeared 4 days later without addition to or change in treatment. CONCLUSION: Transient, noninfectious, crystalline, intrastromal corneal deposits may develop after adjunctive subconjunctival 5-fluorouracil administration.

Vitreous opacities affect scanning laser polarimetry measurements.

PURPOSE: To assess the effect of vitreous opacities on retinal nerve fiber layer retardation measurements obtained during scanning laser polarimetry. METHODS: Scanning laser polarimetry was performed in two eyes of two patients with vitreous opacities. RESULTS: The presence of a vitreous opacity within the measurement ellipse during scanning caused a marked, localized increase in polarization in the area of the opacity. This falsely increased the value obtained for the mean retinal nerve fiber layer thickness. Retinal nerve fiber layer thickness values were reduced when the opacity was not incorporated into the measurement ellipse. CONCLUSION: Artifact introduced by the presence of vitreous opacities can affect scanning laser polarimetry measurement reliability.

Glaucoma drainage tube kink after pars plana insertion.

PURPOSE: To describe focal obstruction of drainage tubes by kinking at the scleral entry site after pars plana insertion. METHODS: Case study. RESULTS: Three eyes of three patients underwent uncomplicated placement of a Baerveldt implant into the vitreous cavity at the time of pars plana vitrectomy. Intraocular pressure remained increased after the procedure without evidence of flow. Surgical exploration and modification of the tube placement resulted in immediate intraocular pressure reduction. Compression of the tube at the scleral entry site was confirmed intraoperatively in all eyes by ultrasound biomicroscopy. CONCLUSION: Kinking of the tube at its scleral entry site should be recognized as a possible cause of increased intraocular pressure without bleb formation after pars plana insertion of a glaucoma drainage implant.

Low-dose 5-fluorouracil trabeculectomy as initial surgery in uncomplicated glaucoma: long-term followup.

OBJECTIVE: To compare the effectiveness of trabeculectomy with adjunctive, low-dose, subconjunctival 5-fluorouracil (5-FU) to trabeculectomy alone in patients with uncomplicated glaucoma undergoing their first incisional surgical procedure. DESIGN: Retrospective, nonrandomized comparative trial. PARTICIPANTS: Consecutive series of 52 patients and 74 control subjects. INTERVENTION: Trabeculectomy was performed in all patients. Study patients received adjunctive, subconjunctival injections of 5-FU up to 14 days from the date of surgery. MAIN OUTCOME MEASURES: Intraocular pressure, number of postoperative antiglaucoma medications, interventions, and complications were evaluated. RESULTS: Mean followup for all patients was 58.1 +/- 44.1 months (range, 1.1-159.9 months). Mean followup for successful eyes was 55.9 +/- 47.1 months (range, 7.6-159.9 months). The cumulative 5-year success (intraocular pressure [IOP] < or = 21 mmHg) was 77.8% in the 5-FU group and 62.2% in the control group (P = 0.02, Wilcoxon test. Complete success (IOP < or = 21 mmHg without medications) at 5 years was lower in both the 5-FU group (72.3%) and the control group (51.3%). Postoperative mean IOP at 5 years for all successful patients was lower in eyes receiving 5-FU (10.7 +/- 3.6 mmHg vs. 16.0 +/- 6.1 mmHg [P = 0.02, t-test]). For those patients considered to be complete successes, there was no difference in IOP between the two groups of patients at any evaluated time interval. Patients in the 5-FU group were using 0.7 +/- 1.1 medications at final followup compared with 1.8 +/- 1.4 medications in the control group (P = < 0.0001, t test). Bleb-related ocular infection occurred in 6.3% of patients and was more common in patients receiving 5-FU than controls (6 of 52 vs 2 of 74, respectively; P = 0.05, Fischer's exact test). CONCLUSIONS: Adjunctive, low-dose 5-FU at the time of initial surgery in uncomplicated glaucoma improves long-term IOP control and reduces the need for postoperative, antiglaucoma therapy. Eyes receiving 5-FU are at greater risk of developing late bleb-related ocular infection.