Comparison of Phacotrabeculectomy and Phacotrabeculectomy with Subconjunctival 5-Fluorouracil

Introduction: Glaucoma is the second leading cause of blindness worldwide. Phacotrabeculectomy is a technique in which glaucoma and cataract surgery performed. Methods: Prospective study was carried out in the department of glaucoma at Lumbini Eye Institute, Bhairahawa.100 patients who underwent phacotrabeculectomy within a period of two years. Patients were divided into two groups those who received 5FU (n=47) and no antifibrotic agent (n= 53) Results: The age range was from 38 to 80 years; mean age of 62.97±9.14 SD. 55% were male and 45% were female.The postoperative IOP reduction in last followup group A was mean=13.08±1.57SD and mean=13.23±1.73SD in group B. This was statically significant with P <0.001. Bleb survival was almost similar in two groups 3.17(78.31%) in group A and 3.20 (78.93%) in group B. 85% visual acuity was improved in both groups. Conclusions: Phacotrabeculectomy and phacotrabeculectomy with inj. 5FU, both were equally effective surgical techniques in terms of visual acuity, IOP control and bleb survival.There was no significant statistical difference vis-à-vis the success of Phacotrabeculectomy using of either these two techniques. _______________________________________________________________________________________


INTRODUCTION
Glaucoma is the second leading cause of irreversible blindness worldwide. There are at least 60.5 million people with open angle glaucoma (OAG) and angle closure glaucoma (ACG) in 2010, increasing to 79.6 million by 2020. Asians will represent 47%. Bilateral blindness will be present in 4.5 million people with OAG and 3.9 million people with ACG in 2010, rising to 5.9 to 5.3 million people in 2020. Elevated intraocular pressure (IOP) is the most important risk factor in the development of the diseases. Phacotrabeculectomy is the most commonly performed operation for combined glaucoma surgery. 9

METHODS
This study was carried out in the department of glaucoma at Lumbini Eye Institute, Bhairahawa, Nepal. All subjects were randomly selected. A verbal/written informed consent was obtained from the patients enrolled in the study. Primary open angle glaucoma with significant cataract within a period of two years (August 2012-August 2014) was included. Patients diagnosed with acute angle closure glaucoma, uveitis glaucoma, secondary glaucoma, Lens induced glaucoma, failed trabeculectomy, postpterygium surgery and any intraocular surgery were excluded from the study. Data analysis was performed using the statistical software SPSS 16 version. Comparisons between two groups were analyzed by the chi-square and paired t tests.
Preoperative assessment: Demographic assessment like name, age, gender, address and occupation were evaluated. A brief personal history, medical history, anti-glaucoma drug history and family history were also taken. All patients underwent full ophthalmological examination, including best corrected visual acuity, slit lamp bio-microscopy, anterior chamber depth, Goldmann applanation, central corneal thickness, gonioscopy, humphary field analyser 24-2 and 10-2, disc photograph and OCT. Fundus examination was performed with both direct and indirect methods. Cataract was graded by using of Lens opacities classification system (LOCS) with the standard photograph. 1

Indication for combined surgery:
a) Glaucoma under borderline control, despite maximum tolerable medical therapy. b) Adequate IOP control, but significant drug-induced side effect. C) Adequate IOP on well-tolerated medical therapy, but advanced glaucomatous optic atrophy. d) Uncontrolled glaucoma, but urgent need to restore vision. 11 Operative procedure: All surgeries were performed under peribulbar anaesthesia by a single surgeon in the Lumbini Eye Institute, Bhairahawa, Nepal. Phacotrabeculectomy were performed 53 patients in group A and phacotrabeculectomy with 5-Fluorouracil (5FU) 47 patients in group B were evaluated. One-port phacotrabeculectomy surgery was performed with the surgeon sitting superiorly. A fornix-based 4mm conjunctival flap was created with tinotomy scissors. Bipolar cautery was used as needed. A square2x2.0mm partial thickness scleral flap was created towards the limbus with crescent. 12 Paracentesis was made into the clear cornea with a 15° blade. The keratome was used to enter the anterior chamber through the scleral flap than phacoemulsification was carried out. Phacoemulsification was performed in the usual manner. Foldable PC IOL was implanted all cases. Trabeculectomy was done with Kelly's punch followed by Peripheral iridectomy was done for all cases. The scleral flap was closed with 2 interrupted 10.0 nylon sutures at the apices of the square and conjunctiva and tenon's capsule were reposed with 10.0 nylon sutures in the both groups. Following surgery, inj.cefuroxime1mg was injected intracamerally. Inj. 5FU 5mg was injected 180 0 (6'0clock) position subconjunctivally in group B cases at the end of surgery.

Postoperative follow-up:
Post operatively, all patients treated with 1% prednisolone acetate 2 hourly for 2 weeks then tapered according to the anterior chamber inflammatory reaction up to 45 days and 0.3% ofloxacin eye drop 4 times a day. Patients were evaluated on the first postoperative day, after 14 days, 1 month, 3 months and every 6 months. Surgical Outcome were defined as IOP<21mmHg without medication, best corrected visual acuity, fundus examination and bleb grading. Bleb scoring was done according to Moorfield Grading System (MBGS). 7

RESULTS
The age ranged from 38 to 80 years; mean age of 62.97± 9.14SD. 55% were male and 45% were female. All two groups had statistically significant lower intraocular pressure at 1 st day, 1-month follow -up, 3-month follow-up, 6-month follow-up and 12-month follow-up compared to preoperative intraocular pressure levels at all times intervals measured (p<0.001). Intraocular pressures were slightly higher in both groups in 14-day follow-up 15.1±2.87SD in group A and 15.23±2.45SD in group B. Bleb survival was almost similar in both groups 3.17(78.31%) in group A and 3.20 (78.93%) in group B. 85% visual acuity was improved in both groups.   13.5 mmHg on a mean of 0.6 and 0.8 glaucoma drops in the PMT and MT groups, respectively. In the PMT final visual acuity improved by at least one Snellen line in 81.1% and was worse in a single eye. It was concluded that IOP control following combined surgery by PMT is as good as following MT alone. 10 In our study, postoperative final visual acuity was improved 84.91% in group A and 85.11% in group B, preoperative mean IOP and the final follow-up IOP values were significantly different between group A and group B and bleb survival was almost similar in the two groups in 12 months follow-up.

CONCLUSIONS
Phacotrabeculectomy and phacotrabeculectomy with inj. 5-FU, both were equally effective surgical techniques in terms of visual acuity, IOP control and bleb survival.
There was no significant statistical difference vis-à-vis the success of Phacotrabeculectomy using of either these two techniques.