histopathologic evaluation of trabeculectomy specimens and surgical results in patients with chronic primary glaucoma

purpose: to evaluate the histopathologic features of trabeculectomy specimens and the results of tra-beculectomy in relation with these features in patients with chronic primary glaucoma. methods: this interventional case series included 30 eyes of 28 patients with primary chronic glaucoma who underwent trabeculectomy between 2004 and 2006. each case was followed for 6 months post-operatively. histopathologic features and results of surgery were evaluated. the surgery considered as successful when resulted in intraocular pressure (iop) <21 mmhg without antigiancoma medication and as failed when resulted in iop of > 21 mmhg and need to anti-glaucoma agent. results: mean age of patients was 59 (range 20 to 90) years and 18 patients (64.3%) were male. seventeen patients had chronic primary open angle glaucoma and 11 had primary chronic closed angle glaucoma. the operation was performed as fornix-based method in 16 eyes and limbal-based in 14. the surgery was successful in 26 (86.7%) and failed in 4 (13.3%). the content of trabeculectomy specimens in the successful cases included trabecular meshwork in 15 (57.7%), only scleral in 6 (23.1%) and only corneal tissue in 5 (19.2%) cases. out of 15 cases with content of trabecular meshwork, 7 cases (26.9% of successful cases) had all three portions of cornea, trabecular meshwork and sclera. this figure was not observed in any failed cases. the content of trabeculectomy specimens in failed cases included tra-becular meshwork in 3 cases and only sclera in one case. conclusion: the size and position of the site of trabeculectomy is variable and seems to have significant effects on the success rate of the surgery such that surgical resection anterior to the scleral spur increases the chance of surgical success.