Aqueous shunt exposure repair: outcomes and risk factors for recurrence.

OBJECTIVE: To investigate the outcomes of aqueous shunt exposure repair and to identify risk factors for recurrent exposure after surgical repair. METHODS: This is a retrospective interventional case series of consecutive patients who underwent repair of an exposed aqueous shunt. Demographic and clinical data were extracted from the patients' records and survival analysis was employed to determine the probability of survival of the repair without further exposure. Cox proportional regression analysis was utilised to identify potential risk factors for failure of the repair surgery. RESULTS: Seventy-six eyes of 76 patients were included in the study. The probability of survival without further exposure was 76.2% (CI 66.9-86.8%), 72.7% (CI 62.8-84.1%) and 54.7% (40.5-73.7%) at 1,2 and 4 years, respectively. No eye in which the tube was repositioned in the anterior chamber or in the sulcus (n = 9; 11.8%) developed a recurrence of the exposure. A shorter interval from the time of tube insertion to the repair surgery (HR 2.87 [CI 1.11-7.39]; p = 0.03; reference longer interval), a history of previous surgical revision (HR 3.06 [1.15-8.12]; p = 0.02; reference no prior revision) and the use of a human pericardial donor patch at the time of revision (HR 3.43 [1.16-10.13]; p = 0.03; reference other than pericardium) was associated with an increased risk of exposure recurrence. CONCLUSION: Aqueous shunt exposure revision is associated with reasonable mid and long term success. A shorter interval from tube insertion to exposure revision, previous revisions and the use of a human pericardium patch were associated with increased risk of failure.

Risk factors for bleb-related infection following trabeculectomy surgery: ocular surface findings-a case-control study.

PURPOSE: Bleb-related infection (BRI) is a devastating complication of trabeculectomy surgery. The aim of this study was to identify ocular risk factors for BRI with specific emphasis on ocular surface parameters. It has been suggested that the frequency has increased since the introduction of antimetabolites, particularly mitomycin C. DESIGN: A case-control study. METHOD: A clinical study of BRI following trabeculectomy surgery to investigate risk factors by documenting historical data review from patients records, self-reported questionnaire specific to ocular surface symptoms and a repeat detailed clinical examination of the lid, ocular surface and tear film. RESULTS: Twenty-eight cases and 31 controls were assessed. The overwhelming risk factor for development of BRI was chronic blepharitis (multivariate analysis OR 16.3 (1.687 to 157.44) p=0.016). No increased risk was identified with the antimetabolite used during trabeculectomy surgery (p=0.38) or the type of conjunctival reflection adopted for surgery (p=0.38). Neither age (p=0.32) nor dry eyes (p=0.13) were identified as risk factors. CONCLUSION: An increased risk of BRI was identified in eyes with chronic blepharitis. To minimise the risk of infection following trabeculectomy surgery, it may be advisable to manage the lid disease in these patients prior to performing trabeculectomy surgery or offer an alternative treatment such as a shunt. TRIAL REGISTRATION NUMBER: RAIQ1001.

Comparison of handheld rebound tonometry with Goldmann applanation tonometry in children with glaucoma: a cohort study.

OBJECTIVE: To test agreement of two methods to measure intraocular pressure (IOP): rebound tonometry (RBT) and gold standard Goldmann applanation tonometry (GAT) in children with glaucoma. DESIGN: Observational prospective cohort study. SETTING: Tertiary paediatric glaucoma clinic at a single centre. PARTICIPANTS: 102 individuals attending a paediatric glaucoma clinic, mean (SD) age 11.85 (3.17), of whom 53 were male. PRIMARY AND SECONDARY OUTCOME MEASURES: Intraocular pressure, central corneal thickness, child preference for measurement method. RESULTS: Limits of agreement for intraobserver and interobserver were, respectively, (-2.71, 2.98) mm Hg and (-5.75, 5.97) mm Hg. RBT frequently gave higher readings than GAT and the magnitude of disagreement depend on the level of IOP being assessed. Differences of 10 mm Hg were not uncommon. RBT was the preferred method for 70% of children. CONCLUSIONS: There is poor agreement between RBT and GAT in children with glaucoma. RBT frequently and significantly overestimates IOP. However, 'normal' RBT readings are likely to be accurate and may spare children an examination under anaesthesia (EUA). High RBT readings should prompt the practitioner to use another standard method of IOP measurement if possible, or consider the RBT measurement in the context of clinical findings before referring the child to a specialist clinic or considering EUA.

Changing trends in the incidence of bleb-related infection in trabeculectomy.

AIM: To investigate the incidence of late onset bleb-related infection (BRI) following Mitomycin C (MMC) augmented trabeculectomy procedures at a single institution. METHODS: This was a retrospective case series analysis of late onset BRI, defined as either blebitis or endophthalmitis occurring at least 1 month following a glaucoma filtration procedure. Data collected from hospital charts included the position of the conjunctival flap base. Two cohorts were examined: the first a sample of 194 intraoperative MMC augmented trabeculectomies undertaken over a 4-year period from 1993 to 1997, and the second a sample of 764 MMC trabeculectomies performed in a 4-year period between the years 1999 and 2005. RESULTS: A total of 11 cases of BRI (cumulative incidence 5.7%) were identified in the cohort from 1993 to 1997. BRI cases had trabeculectomies performed with a limbus-based conjunctival flap and presented at a median IQR 14.8 (9.4-42.9) months after surgery. In the 1999-2005 cohort, nine cases of BRI were identified (cumulative incidence 1.2%). All these BRI cases had a fornix-based conjunctival flap and presented at a median IQR 19.2 (6.1-44.1) months after trabeculectomy surgery. CONCLUSION: This study found that the incidence of BRI was higher in MMC augmented trabeculectomy shortly after the introduction of MMC, but subsequently reduced to a lower level. While many changes in surgical technique had occurred in the intervening period, the most significant change was from limbus-based to fornix-based conjunctival flap. However, the retrospective nature of the study prevents the authors from concluding that there is a causative relationship between changes in surgical technique and BRI.

Successful Treatment of Subretinal Neovascularization with Intravitreal Ranibizumab in a Child with Optic Nerve Head Drusen.

An 11-year-old boy presented with visual acuity reduced to 20/100 in his left eye. Investigations revealed optic disc drusen associated with a minimally classic choroidal neovascular membrane. The patient underwent a 3-month course of intravitreal ranibizumab. Six months of follow-up revealed remarkable visual acuity improvement to 20/20 and complete resolution of exudative maculopathy.

Amniotic membrane as an adjunct to donor sclera in the repair of exposed glaucoma drainage devices.

PURPOSE: To describe a novel method of repairing exposed glaucoma drainage devices (GDD) using amniotic membrane transplantation (AMT) in place of conjunctiva to cover donor sclera when conjunctival closure is hampered by adjacent scarring. DESIGN: Retrospective noncomparative interventional case series. METHODS: Consecutive case series of nine GDD erosions over 5 years repaired by a double-layer technique of scleral allograft plus AMT. RESULTS: Successful repair was achieved in seven cases. One GDD plate re-eroded after pars plana vitrectomy; a second leaked from the tube entry site. CONCLUSIONS: AMT is a safe and useful conjunctival substitute to cover donor sclera in situations where conjunctival scarring might otherwise preclude successful repair.

Conjunctival lymphoid hyperplasia presenting with bilateral panuveitis.

PURPOSE: To report on a case of bilateral conjunctival lymphoid hyperplasia presenting with bilateral panuveitis in a female patient. DESIGN: Observational case report. METHODS: In this case excisional biopsy indicated lymphoid tissue. Immunohistochemistry showed a follicular architecture with appropriate zoning of B and T lymphocytes. RESULTS: Causes of panuveitis were considered and excluded based on a detailed history, physical examination, and laboratory investigations. The bilateral panuveitis resolved on topical corticosteroids and visual acuity returned to normal. CONCLUSIONS: Ocular adnexal lymphoproliferative lesions consist of a spectrum of disease entities, including reactive lymphoid hyperplasia, atypical lymphoid hyperplasia, and lymphoma. There are no established clinical criteria to differentiate between these lesions. This case highlights the importance of a thorough ophthalmic examination in these patients, as an intra-ocular inflammatory process may accompany the conjunctival findings. Furthermore, we advocate periodic follow-up examinations because of the small potential risk of developing ocular or systemic lymphoma in these patients.