Changes in Axial Length Following Trabeculectomy and Ahmed Glaucoma Valve Implantation

ABSTRACT

PURPOSE: This study examines the changes in axial length after trabeculectomy and Ahmed glaucoma valve implantation surgery. METHODS: In the forty three eyes of the 42 patients who had the uncontrolled glaucoma, 22 eyes of 21 patients having trabeculectomy and 21 eyes of 21 patients having Ahmed glaucoma valve implantation from October 2004 to September 2005 at Kim's Eye Hospital were analyzed prospectively. These patients had IOP and axial length measurements preoperatively, at 1 week, 1 month, and 3 months after surgery and refractive power measurements preoperatively, at 3 months after surgery. Axial length was measured by IOL Master(R). RESULTS: There was a statistically significant reduction in IOP after 3 months of 26.6+/-11.2 mmHg overall, 22.4+/-8.4 mmHg following trabeculectomy, and 30.9+/-12.3 mmHg after Ahmed glaucoma valve implatation (p<0.001). There was a statistically significant reduction in axial length after 3 months of -0.24+/-0.10 mm overall, -0.21+/-0.1 mm after trabeculectomy and -0.28+/-0.1 mm after Ahmed glaucoma valve implantation. CONCLUSIONS: There was a statistically significant decrease in axial length after both trabeculectomy and Ahmed glaucoma valve implantation. We must consider the influence of axial length change on refraction in planning combined glaucoma and cataract surgery or future IOL implantation.