***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Aim : To establish the incidence , time course , and severity of conjunctival wound leakage following trabeculectomy  , and also to establish whether early wound leakage adversely affects the ultimate outcome of the surgery . Method : A prospect i ve , observational case series of sequential trabeculectomies performed in a single institution over a 12 month period . Data sets on 286 operations were analysed . A fornix based conjunctival flap was used in 254 cases and a limbus based conjunctival flap in 41 cases . At every postoperative visit trabeculectomies were assessed for four grade s of leakage ( none ; mild ; moderate ; severe ) , and for success or failure at the 6 month follow up post surgery . Pressure was applied to the trabeculectomy bleb to record the maximum rates of leakage and improve kappa statistics . Study clinicians were vali date d with respect to their scoring of leaks before starting the study . Results : 169 of the 286 trabeculectomies ( 59 % ) showed leakage at some stage postoperatively . 159 of 245 fornix based flaps ( 65 % ) leaked compared with 10 of 41 limbus based flaps ( 24 % ) . Median time to leak was 3.5 ( range 0–408 ) days . Median duration of leakage was 14 ( range 2–457 ) days . 14 ( 5 % ) of trabeculectomies failed completely . A further 40 ( 14 % ) were a partial failure . In total , 23 of 117 ( 20 % ) without postoperative leaks partially or completely failed compared with 31 of 169 ( 18 % ) with leaks . Cross tabulation of partial and complete failure by leak shows no evidence of an adverse effect of leaking on the outcome ( χ2 = 1.81 , p = 0.4 ) . Conclusions : There is no evidence to support the hypothesis that early postoperative leakage of fornix based conjunctival flaps affects the outcome of trabeculectomy OBJECTIVE To compare the effectiveness of limbus-based and fornix-based conjunctival flaps in fellow eyes of the same patients undergoing combined trabeculectomy with phacoemulsification .  DESIGN Prospect i ve , nonr and omized comparative ( fellow eye ) study . PARTICIPANTS Forty-four patients and 88 fellow eyes . INTERVENTION Limbus-based conjunctival flap with phacotrabeculectomy was performed in one eye , and a fornix-based conjunctival flap with phacotrabeculectomy was performed in the fellow eyes of the same patients . The patients were followed up for a minimum of 1 year postoperatively for each eye . MAIN OUTCOME MEASURES Preoperative and postoperative visual acuity , intraocular pressure , number of antiglaucoma medications , interventions , and complications were studied . RESULTS At last follow-up visit , visual acuity improved to 20/40 or better in 88.6 % of the limbus-based group and 79.6 % of the fornix-based group . Preoperatively , the mean intraocular pressure in the limbus-based group was 21.4 + /- 4.8 mmHg on a mean of 2.4 + /- 1.2 glaucoma medications ; in the fornix-based group , it was 21.4 + /- 4.3 mmHg on a mean of 2.3 + /- 1.1 medications . Mean intraocular pressure decreased to 15.3 + /- 3.3 mmHg ( P < 0.01 ) on a mean of 0.2 + /- 0.5 glaucoma medications in the limbus-based group ( P < 0.01 ) . In the fornix-based group , mean intraocular pressure at last follow-up visit decreased to 15.3 + /- 4.7 mmHg ( P < 0.01 ) on a mean of 0.2 + /- 0.5 medications ( P < 0.01 ) . Postoperative interventions and complications were not statistically different between the two groups . CONCLUSION With phacotrabeculectomy , limbus-based and fornix-based conjunctival flaps are equally effective in improving visual acuity and lowering intraocular pressure . This variation in conjunctival flap orientation was equally effective in fellow eyes of the same patients , with no difference in postoperative complications or outcomes PURPOSE To determine the efficacy and safety of limbus-based vs fornix-based conjunctival flaps in patients with primary open-angle glaucoma undergoing trabeculectomy combined with phacoemulsification and intraocular lens implantation with adjunctive subconjunctival mitomycin C.  METHODS In a prospect i ve study , 69 eyes of 69 patients with primary open-angle glaucoma , visually symptomatic cataracts , and no previous incisional ocular surgery were r and omly assigned to limbus-based and fornix-based conjunctival flap groups . All patients received trabeculectomy combined with phacoemulsification and posterior chamber lens implantation with 1-minute ( 0.5 mg/ ml ) application of subconjunctival mitomycin C. RESULTS The mean intraocular pressures were significantly ( P < .05 ) lower on significantly ( P < .05 ) fewer medications postoperatively at 1 week , 1 month , 3 , 6 , 9 , 12 , and 15 to 18 months , and at last follow-up in both groups than they had been preoperatively . However , there were no significant ( P > .05 ) differences in postoperative mean intraocular pressure , mean number of medications , and visual acuity between the two groups at any time interval . Hypotony with wound leak was significantly ( P = .019 ) higher in the limbus-based group . Other postoperative complications were not significantly ( P > .05 ) different between the two groups . CONCLUSIONS There was no notable difference in glaucoma control or visual outcome between limbus-based and fornix-based conjunctival flaps in primary trabeculectomy combined with phacoemulsification and lens implantation with adjunctive subconjunctival mitomycin C. The fornix-based flap was as safe as , if not safer than , the limbus-based flap in the glaucoma triple procedure with adjunctive subconjunctival mitomycin We studied prospect ively the results of limbus-versus fornix-based flaps in patients undergoing combined trabeculectomy and phacoemulsification .  We found no significant difference at six months postoperatively in the level of intraocular pressure between the limbus-(16.1 ± 4.1 mm Hg ) and fornix- ( 14.0 ± 3.4 mm Hg , p = 0.161 ) based groups , or in the number of glaucoma medications ( p = 0.0750 ) . The highest intraocular pressure recorded within the first postoperative month was similar between groups ( 18.4 ± 6.9 mm Hg for limbus and 18.5 ± 5.5 mm Hg for fornix , p > 0.900 ) . Postoperative bleb height , extent , and vascularity , as well as chamber depth were statistically similar between groups ( p > 0.05 ) . Postoperative complications were similar between groups . This study indicates that both fornix- and limbus-based flaps may be used safely and effectively when performing a trabeculectomy combined with phacoemulsification PURPOSE To report the 5-year incidence of bleb-related infection after mitomycin C-augmented glaucoma filtering surgery  and to investigate the risk factors for infections . DESIGN Prospect i ve , observational cohort study . PARTICIPANTS A total of 1098 eyes of 1098 glaucoma patients who had undergone mitomycin C-augmented trabeculectomy or trabeculectomy combined with phacoemulsification and intraocular lens implantation performed at 34 clinical centers . METHODS Patients were followed up at 6-month intervals for 5 years , with special attention given to bleb-related infections . The follow-up data were analyzed via Kaplan-Meier survival analysis and the Cox proportional hazards model . MAIN OUTCOME MEASURES Incidence of bleb-related infection over 5 years and risk factors for infections . RESULTS Of the 1098 eyes , a  bleb-related infection  developed in 21 eyes . Kaplan-Meier survival analysis revealed that the incidence of bleb-related infection was 2.2±0.5 % ( cumulative incidence ± st and ard error ) at the 5-year follow-up for all cases , whereas it was 7.9±3.1 % and 1.7±0.4 % for cases with and without a history of bleb leakage , respectively ( P = 0.000 , log-rank test ) . When only eyes with a well-functioning bleb were counted , it was 3.9±1.0 % . No differences were found between the trabeculectomy cases and the combined surgery cases ( P = 0.398 , log-rank test ) or between cases with a fornix-based flap and those with a limbal-based flap ( P = 0.651 , log-rank test ) . The Cox model revealed that a history of bleb leakage and younger age were risk factors for infections . CONCLUSIONS The 5-year cumulative incidence of bleb-related infection was 2.2±0.5 % in eyes treated with mitomycin C-augmented trabeculectomy or trabeculectomy combined with phacoemulsification and intraocular lens implantation in our prospect i ve , multicenter study . Bleb leakage and younger age were the main risk factors for infections Summary A r and omized prospect i ve study was performed to compare the results of  filtering surgery using a  Limbusbased versus a Fornix-based conjunctival flap .  The wound closure of the Fornix-based flap was performed using a running 10/0 nylon suture at the limbus . No statistical significant difference of IOP regulation was found between the two groups . There was a tendency of reduced occurrence of shallow anterior chamber and of less vascularized filtering blebs in the Fornix-based technique We studied 20 patients with uncontrolled symmetric glaucoma who had undergone bilateral trabeculectomy after having received the same medical or laser treatment to both eyes . In each patient , the techniques and suture material used in the two eyes were identical , and the surgeon was the same . The only variable was the type of conjunctival flap used : one eye received a limbal-based flap and the other a fornix-based flap . These patients were followed up from three to 13 months ( median , 8.5 months ) . There was no difference between the two groups in postoperative anterior chamber depth , intraocular pressure control , occurrence of hyphema , size and shape of the bleb , or the rate of complications . The fornix- and limbal-based conjunctival flaps in trabeculectomy were found to yield comparable results in terms of safety and short-term efficacy of pressure control Purpose : To prospect ively compare the influence of fornix‐based and limbus‐based conjunctival flaps on the final outcome and complications of 2‐site phacotrabeculectomy with mitomycin‐C in fellow eyes of patients with bilateral open‐angle glaucoma ( OAG ) . Setting : Glaucoma Unit , Department of Ophthalmology , University of Crete , Crete , Greece . Methods : Twenty‐two patients with bilateral primary OAG and 8 patients with bilateral exfoliative glaucoma had 2‐site phacotrabeculectomy in both eyes . Eyes were r and omly assigned to the fornix‐based flap or limbus‐based flap group by the use of r and om tables . Results : The intraocular pressure ( IOP ) decreased significantly in both groups ( P < .01 ) ; however , there was no statistically significant difference between the groups in the amount of IOP decrease or the number of postoperative antiglaucoma medications after a 1‐year follow‐up . Faster improvement in visual acuity was observed in the fornix‐based group during the first week . The mean time of surgery was 3.5 minutes less in the fornix‐based group . An increased incidence of fibrin exudation , pupillary membrane formation , and capsule opacification was found in eyes with exfoliative glaucoma . The early bleb leakage was 3 times more frequent in the fornix‐based group . Conclusion : The type of conjunctival flap in a 2‐site phacotrabeculectomy did not seem to influence the final outcome . The main advantage of the fornix‐based conjunctival flap is the shorter surgical time and the relatively faster improvement in vision postoperatively . The main disadvantage is more frequent early bleb leakage OBJECTIVE The research ers sought to assess whether the widely used 1994 Cochrane Highly Sensitive Search Strategy ( HSSS ) for r and omized controlled trials ( RCTs ) in MEDLINE could be improved in terms of sensitivity , precision , or parsimony . METHODS A gold st and ard of 1,347 RCT records and a comparison group of 2,400 non-trials were r and omly selected from MEDLINE .  Terms occurring in at least 1 % of RCT records were identified . Fifty percent of the RCT and comparison group records were r and omly selected , and the ability of the terms to discriminate RCTs from non-trial records was determined using logistic regression . The best performing combinations of terms were tested on the remaining records and in MEDLINE . RESULTS The best discriminating term was " Clinical Trial " ( Publication Type ) . In years where the Cochrane assessment of MEDLINE records had taken 
    Output:
    
Trabeculectomy is quite a st and ard procedure and unlikely to induce bias due to surgeon ' performance ' , hence performance bias was not evaluated .
This also applied to postoperative complications , but without any impact on long-term failure rate between the two surgical techniques