***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: Abstract · Background : An investigation was carried out to compare post-operative inflammation following deep sclerectomy with collagen implant ( DSCI ) versus st and ard trabeculectomy . · Methods : In this prospect i ve r and omized study , 46 eyes of 46 Caucasian patients with medically uncontrolled chronic open-angle glaucoma and without previous glaucoma surgery underwent filtering surgery .  Twenty-four eyes underwent DSCI . Twenty-two eyes underwent st and ard trabeculectomy . Pre- and post-operative flare , measured using laser flare photometry , were compared between the two groups . · Results : In both groups , the mean anterior chamber flare increased on the first post-operative day , then decreased progressively . DSCI was associated with lower flare measurements post-operatively . The difference was statistically significant up to 1 month post-operatively : 16.3±7.8 vs 72.5±38.9 ( P<0.001 ) at 1 day , 7.8±4.6 vs 44.7±29.2 ( P<0.001 ) at 1 week , 5.9±1.6 vs 7.0±2.8 ( P=0.012 ) at 1 month , 6.4±1.8 vs 6.5±1.9 ( P=0.77 ) at 2 months , 5.9±1.8 vs 6.1±1.6 ( P=0.65 ) at 3 months . · Conclusion : Surgically induced inflammation can be reduced with DSCI . This may be due to the lack of iridectomy , irrigation , and penetration of the anterior chamber . Eyes at increased risk of post-operative inflammation , such as those with uveitic or traumatic glaucoma , may benefit from this procedure . Further studies are needed to evaluate the long-term functional and anatomical outcomes of DSCI Results of trabeculectomy ( TE ) and viscocanalostomy ( VCO ) were compared in a prospect i ve r and omised study in two fellow eyes of 22 consecutive patients with bilateral symmetrical high-tension glaucoma . Rates of overall surgical success with intraocular pressures ( IOP ) ≤ 18 mm Hg with or without medications were 91 for the TE , and 95 for the VCO group after a mean follow-up of 18 months . Complete success rates without medications were 64 and 59 for TE and VCO groups , respectively ( p=0.750 ) . Both procedures significantly reduced IOP , however , IOP course  following trabeculectomy was significantly lower ( p=0.026 ) . Rates of complications were not found to be different between the two groups of eyes , except for an apparent – though not significant ( p=0.066 ) – increase in cataract progression with TE . Various types of conjunctival blebs were detected in all eyes with surgical success in both groups , however , diffuse , elevated or multi-cystic functional blebs appeared to be more predominant in eyes with TE , compared to the VCO group in which low-lying , localised blebs had a higher incidence ( p=0.015 ) . Viscocanalostomy was found to be a safe and effective filtration technique in patients with uncomplicated high-tension glaucoma , though IOP decrease was more pronounced with trabeculectomy Purpose : To study the need , the safety and the success rate of collagen implant in eyes that underwent deep sclerectomy , a new non penetrating filtration procedure , we compared the results of deep sclerectomy with ( DSCI ) and without ( DS ) collagen implant . Methods : Of 168 patients ( 168 eyes ) with various types of medically uncontrolled open angle glaucoma , 86 ( 86 eyes ) underwent DSCI , and 82 ( 82 eyes ) underwent DS .  Visual acuity , slit lamp examination , intraocular pressure ( IOP ) measurements were performed before surgery and prospect ively at days 1 and 7 and months , 1 , 2 , 3 , 6 , 9 , 12 , 15 , 18 , and 24 after surgery . Deep sclerectomy was performed according to Kozlov 's original technique . The collagen implant drainage device was radially secured in the center of the deep sclerectomy dissection . Results : The mean follow-up period was 9.7 ± 6.5 months for DSCI , and 9.0 ± 4.8 months for DS . The mean preoperative IOP was 26.9 ± 8.8 mmHg for DSCI and 25.8 ± 8.5 mmHg for DS . The mean postoperative IOP and visual acuity were similar between the two groups . Complete and qualified success rates were better when the collagen implant was used ( Log-Rank test : p = 0.0002 and 0.033 for complete and qualified success respectively ) . The need for postoperative glaucoma medications was significantly lower when the collagen implant was used ( 0.2 ± 0.5 versus 0.5 ± 0.7 medication per patient in the DSCI and DS respectively , Student 's t test : p = 0.0038 ) . There was significantly less bleb fibrosis when the collagen implant was used ( 2 % and 11 % in DSCI and DS respectively , p = 0.029 ) . Conclusion : The collagen implant device is safe , increases the success rate of deep sclerectomy , and lowers the need for postoperative glaucoma medications Aims : To compare the long-term effects of low-dosage mitomycin C ( MMC ) in both deep sclerectomy ( DSMMC ) and trabeculectomy ( TPMMC )  on intraocular pressure ( IOP ) . Methods : Analysis of extended follow-up of data from a prospect i ve clinical trial . Forty patients were originally r and omised to undergo either DSMMC ( 19 eyes ) or TPMMC ( 21 eyes ) . Follow-up was performed at postoperative day 1 , weeks 1 , 2 and 3 , as well as months 1 , 3 , 6 , 9 , 12 , 18 , 24 , 36 and 48 . Two- to three-week data were not included in the statistical analysis . Postoperative complications , number of antiglaucoma medications and IOP were recorded at each visit . Complete ( no medications ) and qualified ( with or without medications ) successes were assessed at 2 target IOPs ( ≤21 and ≤17 mm Hg ) and evaluated by Kaplan-Meier curves . Results : At 48 months , the mean IOP ( ± SD ) was 17.6 ± 3.4 and 17.8 ± 3.6 mm Hg in the DSMMC and TPMMC eyes , respectively , a significant reduction from preoperative IOP in each group ( p < 0.0005 ) . Complete success was achieved at the ≤21 mm Hg target IOP in 10 ( 52.6 % ) and 14 ( 66.6 % ) eyes and qualified success in 15 ( 78.9 % ) and 18 ( 85.7 % ) eyes in the DSMMC and TPMMC groups , respectively . There were no differences in the Kaplan-Meier curves . Hypotony and shallow anterior chamber were significantly more frequent in the TPMMC group . Conclusions : Either procedure controlled IOP efficaciously at our endpoint . Low-dosage MMC can be considered a mild enhancement of deep sclerectomy IOP-lowering effect Purpose To compare the intraocular pressure lowering effect and the frequency of postoperative complications in two of the most used filtration surgery techniques : trabeculectomy and non-penetrating deep sclerectomy ( NPDS ) without collagen implants . Methods Thirty-four eyes of 17 patients with medically uncontrolled symmetrical primary open-angle glaucoma were included in the study . One r and omly selected eye per patient had either trabeculectomy or NPDS without collagen implants as the first surgical procedure . The other eye underwent the second filtration surgery technique less than 6 weeks later . Post-operatively , the intraocular pressure ( IOP ) diurnal curves were determined at 1 , 2 , 3 , 6 , 12 and 18 months . The intergroup differences in IOP lowering effect were determined in an analysis of covariance ( ANCOVA ) , with pre-operative IOP as a changing covariate . Kaplan-Meier survival curves were drawn for IOP , and intercurve analysis was performed . Comparisons of the number of post-operative antiglaucomatous medications , as well as of the complication rate , were done by 2 × 2 frequency tables . A p value of less than 0.05 was considered statistically significant . Results There were statistically significant differences in post-operative IOP level between the two groups at 1 , 2 , 3 , 6 , 12 and 18 months , with a lower level in the trabeculectomy group . Using the Kaplan Meier cumulative survival curve , the trabeculectomy patients had a better complete success rate than the NPDS patients at 18 months post-operatively . There were statistically significantly fewer complications  in the NPDS group . Conclusion Trabeculectomy  lowers the IOP more than the NPDS technique . However , the complication rate seems to be lower in NPDS Purpose : To compare IOP behavior after deep sclerectomy ( DS ) and trabeculectomy with the Crozafon-De Laage Punch ( TP ) , using low-dosage intraoperative mitomycin C ( MMC ) in both techniques . Methods : The study was a prospect i ve r and omized clinical trial . All patients met inclusion and exclusion criteria , and were scheduled for glaucoma surgery . Forty patients were r and omized to undergo either a nonpenetrating DS with MMC ( DSMMC ) ( 19 eyes ) or a TP with MMC ( TPMMC ) ( 21 eyes ) . Postoperative examinations were performed at the 1st day , the 1st , 2nd and 3rd weeks and the 1st , 3rd , 6th , 9th and 12th months . Postoperative complications , number of antiglaucoma medications and the IOP level were checked at each control . Complete success ( without antiglaucoma medications ) and qualified success ( with or without medications ) were assessed at two target IOP levels , namely ≤21 and ≤17 mm Hg in both groups . Moreover , the success rates at ≤21 mm Hg target IOP level were compared with those from previous series of patients who had undergone DS without MMC ( historical control group ) . Results : Data from all eyes were available until the 12th month . The mean preoperative IOP ± SD was 29.6 ± 5.8 mm Hg in DSMMC eyes , 28.0 ± 6.0 in TPMMC eyes ; the mean IOP at the 1st postoperative day was 12.5 ± 4.2 and 13.9 ± 6.5 mm Hg , while at the endpoint the mean IOP was 14.5 ± 4.0 and 16.1 ± 3.8 , respectively , with significant reduction ( p < 0.0005 ) of the preoperative IOP in both groups . Complete success ( ≤21 mm Hg target IOP ) in 15 eyes ( 78.9 % ) of the DSMMC group and in 15 eyes ( 71.4 % ) of the TPMMC group was respectively found , while qualified success was achieved in all the eyes . When a ≤17 mm Hg target IOP was considered , complete success in 12 eyes ( 63.1 % ) and 13 eyes ( 61.9 % ) , and qualified success in 13 eyes ( 68.4 % ) and 15 eyes ( 71.4 % ) were found in the DSMMC and TPMMC groups , respectively . No significant intergroup differences were found in terms of success rate . There is no statistical significance in the Kaplan-Meier cumulative survival curves as for complete and qualified success rate in both surgical groups for a ≤17 mm Hg target IOP ( log rank , p = 0.918 and p = 0.429 , respectively ) . As for the frequency of postoperative complications , hypotony and shallow anterior chamber were significantly more frequent in TPMMC when compared with the DSMMC group . The historical comparison between the DSMMC group and simple DS cases shows no significant difference between the groups , with a mild positive trend in DSMMC when compared with DS eyes . Conclusions : Both techniques , DSMMC and TPMMC , control IOP efficaciously at our endpoint . Our results indicate that low-dosage MMC can be considered a mild enhancement of DS IOP lowering effect without any negative effect on the well-known intra- and postoperative safety of the technique Purpose To compare the intraocular pressure-lowering effect and safety of viscocanalostomy and trabeculectomy with mitomycin C. Methods Twenty-five patients with bilateral primary open-angle glaucoma were enrolled in a prospect i ve clinical study . The eyes of each patient were r and omly assigned to receive viscocanalostomy in one eye and trabeculectomy with mitomycin C in the other eye . The patients were followed up for 12 months . At each visit , best-corrected visual acuity , intraocular pressure , and the appearance of the surgical wound , anterior chamber , and indirect ophthalmoscopy were recorded . Results The mean baseline intraocular pressure was 25.0±2.2 mmHg in viscocanalostomy-treated eyes and 24.8±2.6 mmHg in trabeculectomy-treated eyes . The mean postoperative intraocular pressure was 15.3±1.7 mmH 
    Output:
    
This review provides some limited evidence that control of IOP is better with  trabeculectomy  than viscocanalostomy .
This may reflect surgical difficulties in performing non-penetrating procedures and the need for surgical experience .
Since it is unlikely that better IOP control will be offered by NPFS , but that these techniques offer potential gains for patients in terms of quality of life , we feel that such a trial is likely to be of a non-inferiority design with quality of life measures