Fibrin glue-assisted glaucoma drainage device surgery.

AIM: To describe the use of fibrin glue as a suture substitute for portions of glaucoma drainage device (GDD) surgery. METHODS: Retrospective non-randomised case-control study reviewing 28 consecutive cases of GDD implantation using traditional suture material compared with 14 consecutive cases of GDD implantation using Tisseel fibrin glue (Baxter AG, Vienna, Austria) for portions of the procedure. The fibrin glue was used to close the conjunctiva, secure the pericardium patch graft and secure the tube to the sclera. Three-month follow-up data for each group as well as data on operating times, postoperative conjunctival inflammation, drugs used for glaucoma and intraocular pressure (IOP) were evaluated. Statistical analysis was carried out using analysis of variance. RESULTS: The mean (SD) age of the patients in the suture group (17 men and 11 women) was 56.6 (10.5) years and that in the Tisseel-assisted group (8 men and 6 women) was 54.7 (8.6) years (p = 0.56). No significant differences were observed in IOP levels at any time point between the two groups. No significant differences were found for the need for postoperative glaucoma drops or postoperative complication rates in both groups. Conjunctival inflammation was more pronounced in the suture group (p = 0.002) using a standard scale for comparison. The mean (SD) time of surgery was significantly less for the Tisseel-assisted group, 15.0 (3.11) min, than for the suture group, 25.93 (4.04) min (p<0.001). CONCLUSIONS: Tisseel fibrin glue seems to be a safe substitute for some of the sutures used in GDD surgery. Use of Tisseel seems to have no effect on IOP control or complications, whereas it considerably improved postoperative conjunctival inflammation and reduced time of surgery. Further studies are needed to better understand the role of fibrin glue in GDD implantation.

Location of glaucoma drainage devices relative to the optic nerve.

BACKGROUND: Limited data are available to guide optimal positioning of glaucoma drainage devices (GDD) in relation to the limbus and optic nerve. The authors aim to provide guidelines for appropriate and safe GDD implantation. METHOD: The optimal positioning of five different GDD were evaluated using necropsy eyes of varying axial lengths. The dependent variable that was measured was the maximum distance that a GDD could be placed posterior to the limbus while remaining 2 mm away from the optic nerve. RESULTS: The average maximum distance posterior to the limbus of the anterior plate edge ranged between 9.0-15.0 mm in the superotemporal quadrant for the GDD tested. The distances for superonasal, inferonasal, and inferotemporal quadrants ranged between 8.0-14.0 mm, 9.0-14.0 mm, and 11.0-17.0 mm, respectively. The Molteno device could be placed most posteriorly while remaining 2 mm away from the nerve. The Ahmed FP7 and S2 were the least amenable to posterior placement before encroaching on the 2 mm limit. CONCLUSION: The maximum distance that a GDD can be placed posterior to the limbus, before encroachment around the optic nerve, varies between different devices and quadrants of placement. Taking a measurement of the exact distance of the plate from the limbus during GDD surgery is recommended.