***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 compare 90 ° , 180 ° , and 360 ° selective laser trabeculoplasty ( SLT , 532 nm Nd : YAG laser ) with latanoprost 0.005 % for the control of intraocular pressure ( IOP ) in ocular hypertension ( OHT ) and open angle glaucoma ( OAG ) . Methods : A prospect i ve , r and omised clinical trial in the Department of Ophthalmology , St Thomas ’s Hospital , London , and Clayton Eye Centre , Wakefield , West Yorkshire . 167 patients ( 167 eyes ) with either OHT or OAG were r and omised to receive 90 ° , 180 ° , and 360 ° SLT or latanoprost 0.005 % at night and were evaluated at 1 hour , 1 day , 1 week and 1 , 3 , 6 , and 12 months . Results : The mean follow up was 10.3 months ( range 1–12 months ) . Early , transient , complications such as postoperative ocular pain , uveitis , and 1 hour IOP spike occurred in a number of eyes after SLT , with pain being reported more frequently after 360 ° than 90 ° treatments ( p>0.001 ) . Success rates defined in terms of both a 20 % or more and a 30 % or more IOP reduction from baseline measurements with no additional antiglaucomatous interventions were better with latanoprost than 90 ° ( p<0.001 ) and 180 ° SLT ( p<0.02 ) treatments . Differences in success rates between latanoprost and 360 ° SLT did not reach statistical significance ( p<0.5 ) . Success rates were greater with 180 ° and 360 ° compared to 90 ° SLT ( p<0.05 ) . With 360 ° SLT , 82 % of eyes achieved a > 20 % IOP reduction and 59 % a > 30 % reduction from baseline . Although success rates were better with 360 ° than 180 ° SLT treatments , differences did not reach statistical significance . There were no differences with regard to age , sex , race , pretreatment IOP , OHT versus OAG , laser power setting s , and total laser energy delivered between eyes which responded , in terms of a > 20 % and a > 30 % IOP reduction , and those that did not respond with 180 ° and 360 ° SLT treatments . Conclusions : Success rates were higher with latanoprost 0.005 % at night than with 90 ° and 180 ° SLT treatments . 90 ° SLT is generally not effective . 360 ° SLT appears to be an effective treatment with approximately 60 % of eyes achieving an IOP reduction of 30 % or more . Transient anterior uveitis with associated ocular discomfort is not unusual in the first few days after SLT . Late complications causing ocular morbidity after SLT were not encountered Purpose To compare the efficacy of selective laser trabeculoplasty ( SLT ) to argon laser trabeculoplasty ( ALT ) as treatment and retreatment to lower intraocular pressure ( IOP ) in patients with uncontrolled open-angle glaucoma ( OAG ) on maximally tolerated medication therapy with a follow-up of 12 months . Methods A total of 120 eyes of 120 patients with uncontrolled OAG were enrolled in the study . Group A included patients with IOP > 22 mmHg on maximal medical therapy . A total of 43 eyes underwent SLT treatment and 41 eyes underwent ALT treatment . At the end of the follow-up IOP was < 18 mmHg . Group B included patients with IOP > 20 mmHg at 3 months follow-up after SLT or ALT treatment . These patients were retreated r and omly , 18 with SLT and 18 with ALT . Results In Group A at the end of the follow-up there was no statistically significant difference in IOP lowering between SLT ( 6.01 mmHg ) and ALT ( 6.12 ) ( p=0.794 ) . In Group B at the end of the follow-up patients undergoing SLT presented IOP lowering statistically significant to ALT treatment ( 6.24 mmHg and 4.65 mmHg , respectively , p<0.01 ) . Discussion SLT is effective as treatment for patients with OAG and appears to be equivalent to ALT in IOP lowering at 12 months only in patients without a prior treatment . In case of retreatment SLT appears to be better than ALT in IOP lowering Purpose : To study the effectiveness and safety of selective laser trabeculoplasty ( SLT ) on primary open‐angle glaucoma and ocular hypertension in Chinese eyes INTRODUCTION The falling success rate of ALT ( Argon Laser Trabeculoplasty ) has raised the interest in some new laser techniques , such as q-switched Nd : YAG laser trabeculoplasty ( Coherent Selecta 7000 ) . The " selective " laser trabeculoplasty destroys melanosomes of pigmented trabecular meshwork cells , sparing adjacent non-pigmented cells and tissues . AIM Our goal was to establish the IOP lowering effect of selective laser trabeculoplasty ( SLT -- Selecta Laser Trabeculoplasty ) in comparison with ALT . MATERIAL AND METHODS We have examined 27 patients ( 10 men , 17 women ) aged 35 - 82 , with open angle glaucoma and visual field deterioration despite maximal tolerated topical therapy ( 21 patients --POAG , 3 - -NPG , 1 - -pigmentary glaucoma , 1 - -pseudoexfoliative glaucoma , 1 - -juvenile glaucoma ) . One eye of each patient was r and omly chosen for SLT , the other eye underwent ALT . In each method 50 burns were applied in 180 degrees angle with power setting s of 600 - 1000 mW for ALT and energy setting s of 0.5 - 1.4 mJ for SLT . The IOP was measured 1 hour before laser treatment and 1 , 2 , 24 hours and 3 months after treatment . RESULTS The mean initial IOP in eyes selected for SLT was significantly higher ( 21.26 + /- 4.82 mm Hg ) than in eyes selected for ALT ( 20.26 + /- 4.01 mm Hg ) , t-test : p = 0.037 . However , there was no statistically significant difference in the IOP lowering effect between eyes treated with SLT and eyes treated with ALT . The mean IOP drop from the pre-treatment values was -2.85 + /- 4.62 mm Hg after SLT and -2.63 + /- 3.60 mm Hg after ALT ( t-test , p = 0.84 ) . All values : 2 , 24-hours and 3 months after treatment were significantly lower than pre-treatment values in both groups ( t-test , p < 0.03 ) . Only in the 1st hour after SLT the IOP drop was not significant . There was a significant correlation between the amount of pigment on the trabecular meshwork and the IOP fall ( U Mann-Whitney test ) . In SLT group 6 patients ( 21 % ) developed mild iritis during 1st day after laser treatment , which disappeared after fluorometholon drop therapy . CONCLUSION Both methods --SLT and ALT -- have equivalent IOP lowering effect in short time observation ( 3 months ) . Due to entirely novel mode of Selecta laser action , long term results may show significant differences AIMS To compare the effectiveness of selective laser trabeculoplasty ( SLT , a 532 nm Nd : YAG laser ) with argon laser trabeculoplasty ( ALT ) in lowering the intraocular pressure ( IOP ) in patients with medically uncontrolled open angle glaucoma . METHODS A prospect i ve r and omised clinical trial was design ed . Patients were r and omised to treatment with either SLT or ALT and were evaluated at 1 hour , 1 week , 1 , 3 , and 6 months post-laser . RESULTS There were 18 eyes in each group . Baseline characteristics were similar in both groups . In the SLT group the mean IOP at baseline , 1 , 3 , and 6 months was 22.8 ( SD 3.0 ) , 20.1 ( 4.6 ) , 19.3 ( 6.0 ) , and 17.8 ( 4.8 ) mm Hg , respectively . In the ALT group , the mean IOP at baseline , 1 , 3 , and 6 months was 22.5 ( 3.6 ) , 19.5 ( 4.7 ) , 19.6 ( 5.6 ) , and 17.7 ( 3.3 ) mm Hg , respectively . There was a greater anterior chamber reaction , 1 hour after SLT v ALT ( p < 0.01 ) . Patients with previous failed ALT had a better reduction in IOP with SLT than with repeat ALT ( 6.8 ( 2.4 ) v 3.6 ( 1.8 ) mm Hg ; p = 0.01 ) . CONCLUSION SLT appears to be equivalent to ALT in lowering IOP during the first 6 months after treatment . There is a slightly greater anterior chamber reaction 1 hour after SLT . Patients with previous failed ALT had a significantly greater drop in IOP when treated with SLT vALT . These results need to be confirmed with a larger sample size Objective To compare the effectiveness of argon laser trabeculoplasty ( ALT ) and selective laser trabeculoplasty ( SLT ) in lowering intraocular pressure ( IOP ) in younger patients ( age 60 or less ) . Methods This was a prospect i ve r and omized control trial . Forty-two young patients ( age 29 to 60 y ) had 1 eye r and omized to ALT ( n=22 ) or SLT ( n=20 ) .  IOP was measured before laser and 1 hour , 1 day , 6 weeks , 3 months , every 3 months until 2 years , and then yearly postlaser . Chi-square analysis and Student t test were used to determine statistical significance . Results The mean IOP before treatment was 21.9 mm Hg for ALT and 19.1 mm Hg for SLT with no statistical difference between the groups ( P>0.05 ) . At 2 years , 86.4 % of ALT and 75.0 % of SLT eyes required no further surgical intervention ( laser trabeculoplasty or trabeculectomy ) . During the same time period , there was a statistically significant IOP decrease of 11.1 % after ALT ( P=0.01 ) and 7.7 % after SLT ( P=0.01 ) with no statistical difference between the lasers ( P>0.05 ) . Conclusions In younger patients , both ALT and SLT have a significant ocular hypotensive effect 2 years after treatment , with no differences in outcome identified between the laser modalities BACKGROUND Argon laser trabeculoplasty ( ALT ) and selective laser trabeculoplasty ( SLT ) are treatments for open-angle glaucoma . Many patients have previously received ALT but could benefit from further treatment . The purpose of this study was to examine whether SLT provided clinical benefit for patients who had previously received complete argon treatment . METHODS This was a prospect i ve , partially r and omized , comparison study . The study compared the effect after 1 year of SLT in patients with open-angle glaucoma ( primary , pigmentary , or pseudoexfoliation ) who had previously received 360 degrees of ALT with the effect of  laser treatment ( ALT or SLT ) given for the first time in patients with this condition . Ninety-six subjects were given 180 degrees of laser trabeculoplasty . When both eyes qualified for treatment , the first eye treated was included in the analysis . Twenty-seven subjects were treated with SLT after previously receiving 360 degrees of ALT therapy ; the remainder were given their first laser treatment , 30 being r and omly assigned by coin toss to receive SLT and 39 to receive ALT . RESULTS The mean intraocular pressure ( IOP ) before treatment was 21.5 mm Hg ( SLT after ALT ) , 22.9 mm Hg ( SLT ) , and 22.0 mm Hg ( ALT ) , with no statistical difference among the groups ( p > 0.05 ) . The mean IOP at 1 year was 16.7 mm Hg ( SLT after ALT ) , 17.1 mm Hg ( SLT ) , and 16.4 mm Hg ( ALT ) . The IOP for all 3 groups was statistically significantly lower than at baseline ( p < 0.001 ) , but there were no differences among the groups in this respect ( p > 0.05 ) . At 1 year , the percentage IOP reductions from baseline were 23 % ( SLT ) , 19.3 % ( SLT after ALT ) , and 24 % ( ALT ) . There were no differences among the groups in the number of medications used before the laser , although there was a small but statistically significant decrease in the number of medications used before or after the laser treatment in both the SLT and the SLT after ALT group , but not the ALT group . INTERPRETATION SLT retreatment can produce a clinical ly useful decrease in IOP at 1 year , similar to that obtained by ALT , in patients who have had prior argon laser treatment . SLT may be a useful adjunctive therapy when 360 degrees of ALT has already been performed Introduction : This study evaluated and compared the efficacy of selective laser trabeculoplasty ( SLT ) and argon laser trabeculoplasty ( ALT ) in terms 
    Output:
    
Conclusion In terms of the IOP lowering effect , there is no difference between SLT and ALT .
It is inconclusive whether 90 ° is less efficacious than 180 ° SLT .