Trabeculectomy augmented with mitomycin C application under the scleral flap

• Published in: British journal of ophthalmology 1998-04, Vol.82 (4), p.397-403
• Main Authors: Beatty, S, Potamitis, T, Kheterpal, S, O’Neill, E C
• Format: Article
• Language: English
• Subjects: Adult; Age; Biological and medical sciences; Collagen; Combined Modality Therapy; Data collection; Fibroblasts; Follow-Up Studies; Glaucoma; Glaucoma - physiopathology; Glaucoma - surgery; Humans; Intraocular Pressure; Life Tables; Medical sciences; Middle Aged; Mitomycin - administration & dosage; Mitomycin - therapeutic use; mitomycin C; Nucleic Acid Synthesis Inhibitors - administration & dosage; Nucleic Acid Synthesis Inhibitors - therapeutic use; Original articles - Clinical science; Postoperative period; Retrospective Studies; Risk Factors; Sclera; Success; Surgery; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the eye and orbit; Surgical outcomes; trabeculectomy; Trabeculectomy - methods; Treatment Outcome; Visual Acuity
• ISSN: 0007-1161; 1468-2079
• DOI: 10.1136/bjo.82.4.397

AIM The authors investigated the safety and intraocular pressure (IOP) lowering effectiveness of trabeculectomy augmented with mitomycin C application beneath the scleral flap, and assessed the influence of preoperative risk factors on the surgical outcome. METHODS A retrospective study of 72 consecutive high risk eyes undergoing trabeculectomy with adjunctive mitomycin C (0.2 mg/ml) applied under the scleral flap for 5 minutes was performed. Each eye was ascribed a score based on the number of preoperative risk factors, and categorised into one of three risk factor groups. Success was described as unqualified where IOP was ⩽ 21 mm Hg without medication and qualified where antiglaucomatous therapy was required to maintain it at such a level. A life table analysis of IOP control was calculated. RESULTS The mean IOP (SD) fell from a preoperative level of 28.4 (6.9) to a level of 16.63 (8.06) mm Hg at the last follow up (paired Student’s t test: p< 0.0001). Fifty two eyes (72%) were classed as unqualified successes. The survival rates did not differ significantly between different risk factor groups (log rank test: χ2 = 0.967, p>0.1). The incidence of postoperative complications compared favourably with reports of mitomycin C application between Tenon’s capsule and the undissected scleral bed. CONCLUSION The results illustrate that mitomycin C applied beneath the scleral flap during trabeculectomy in high risk eyes is associated with a success rate comparable to other modes of application. The incidence of potentially serious complications such as conjunctival wound leak and prolonged hypotony was lower than previously published data reporting sub-Tenon’s administration of mitomycin C. The number and nature of preoperative risk factors do not appear to influence the surgical outcome. A possible mechanism of action is proposed.