A comparative study of small incision cataract surgery withtrabeculectomy and extra capsular cataract extraction with trabeculectomy in efficacy of reduction in intra ocular pressure

INTRODUCTION: Glaucoma is a chronic progressive optic neuropathy caused by a group of ocular conditions, which lead to damage of the optic nerve with loss of visual function. Most common risk factor is raised intra ocular pressure. Glaucoma is a group of diseases characterized by visual field changes and progressive optic neuropathy for which raised Intra ocular pressure is a risk factor. Glaucoma is the leading cause of irreversible blindness throughout the world; glaucoma coexisting with cataract is commonly prevalent among elderly patients. The frequent coexistence has led to many ideas as to how best to control glaucoma and at the same time improve the vision. Many successful designs of combined operation have been tried in last 10 years such as ECCE, ICCE and SICS, IOL implantation combined with new filtering procedures. Glaucoma triple procedures can provide good visual rehabilitation and IOP control in cases of co-existing cataract and primary open angle glaucoma. SICS has reduced surgical trauma and induced astigmatism to such a degree that, when combined with trabeculectomy, one could expect visual performance and intraocular pressure control as good as that with two separate procedures. This study is undertaken to compare the efficacy of reduction in IOP between extra capsular cataract extraction with trabeculectomy and small incision cataract surgery with trabeculectomy. AIM OF THE STUDY: To compare the efficacy of reduction in IOP between small incision cataract extraction and posterior chamber intra ocular lens implantation with trabeculectomy and extra capsular cataract extraction and posterior chamber intra ocular lens implantation with trabeculectomy in cases of glaucoma associated with cataract. MATERIALS AND METHODS Prospective, randomized and comparative type of study involving 50 eyes of 50 patients with glaucoma and cataract undergoing small incision cataract surgery and posterior chamber intraocular lens implantation with trabeculectomy and extra capsular cataract extraction and posterior chamber intraocular lens with trabeculectomy in Government Rajaji Hospital, Madurai Medical College, Madurai. Duration of study This study was done for a period of 1 year from January 2004 to January 2005, The follow up of the patients was done for a period of 12 months with follow ups on 2nd week, 4th week, 6th week, 3rd month, 6th month and 12th month. Inclusion criteria All cases of primary open angle glaucoma, primary angle closure glaucoma and secondary angle closure glaucoma where in IOP was not controlled by maximum medical therapy to less than 21 mm Hg having visually significant cataract with best corrected visual acuity 6\12 and less, were selected for the study. Exclusion criteria • Eyes with other types of glaucoma • Traumatic cataract • Complicated cataract • Subluxation of lens • Fundus pathology affecting visual acuity • Patients with corneal opacity • Eyes with prior filtering surgery Methodology Among the patients who were seen during the recruitment period in the ophthalmology department of Government Rajaji Hospital, we selected 50 eyes of 50 patients who satisfied our criteria to undergo surgery. All the patients enrolled in our study received a standard ophthalmological examination which included recording of best-corrected visual acuity, which was determined by subjective and objective refraction with standardized snellen’s chart. CONCLUSION: Our study shows small incision cataract surgery with trabeculectomy has better efficacy in reduction of IOP than extra capsular cataract extraction with trabeculectomy. Also small incision cataract surgery with trabeculectomy gives better IOP control, better visual results and early visual rehabilitation, good filtering bleb and lesser postoperative complications than extra capsular cataract extraction with trabeculectomy. Since our study is a short term of one year follow up only, further studies are needed for long-term results.