Use of trypan blue to assess lymphatic function following trabeculectomy.

IMPORTANCE: To illustrate the importance of lymphatic drainage in assessing trabeculectomy bleb function using intracameral trypan blue. BACKGROUND: To study the lymphatic drainage of trabeculectomy blebs using trypan blue, correlate with bleb function and classify them accordingly. DESIGN: Prospective cross-sectional study in a tertiary care centre. PARTICIPANTS: Thirteen glaucoma patients post-trabeculectomy were studied. METHODS: Trypan blue was injected into the anterior chamber. MAIN OUTCOME MEASURES: The duration taken for dye to stain a drainage bleb or lymphatics is recorded. The extent of the lymphatic structures were measured in clock hours. Intraocular pressure (IOP) prior to surgery was recorded. RESULTS: Eight post-trabeculectomy subjects with dye stained lymphatic vessels had lower IOP (12.6 mmHg, P = .013) compared to the five with no lymphatic vessel staining (mean IOP 23.6 mmHg). Lymphatic extent was inversely related to IOP (P = .021). CONCLUSIONS AND RELEVANCE: Eyes with lymphatic connections to drainage blebs had lower IOP and reduced requirement for topical medications. The extent of lymphatic connection to drainage blebs is related to lower IOP.

Use of trypan blue as an aqueous tracer dye to investigate hypotony where cyclodialysis cleft is suspected.

IMPORTANCE: A new method to help diagnose suspected cyclodialysis clefts. BACKGROUND: To study the use of trypan blue stained aqueous flow patterns in diagnosing causes of hypotony where cyclodialysis clefts were suspected. DESIGN: A case series in a tertiary care centre. PARTICIPANTS: Ten subjects presenting with persistent hypotony and retinal changes. METHODS: Trypan blue was injected into the anterior chamber. MAIN OUTCOME MEASURES: The pattern of dye flow in the anterior chamber was categorized. Intraocular pressure prior to surgery was recorded. RESULTS: All seven subjects with cyclodialysis clefts had a preferential flow to the cleft region. Two hypotonous subjects post trabeculectomy had rapid (5 seconds) and extensive lymphatic staining (6 o'clock hours extent) without visible bleb formation. CONCLUSIONS AND RELEVANCE: Preferential flow of dye to the limbus is a reliable sign of cyclodialysis cleft and helps localize cleft extent. A new cause of hypotony, "lymphatic overdrain," is identified.