***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: PURPOSE To determine if photodynamic therapy with verteporfin ( Visudyne ; Novartis AG , Bülach , Switzerl and ) , termed verteporfin therapy , can safely reduce the risk of vision loss compared with a placebo ( with sham treatment ) in patients with subfoveal choroidal neovascularization caused by age-related macular degeneration who were identified with a lesion composed of occult with no classic choroidal neovascularization , or with presumed early onset classic choroidal neovascularization with good visual acuity letter score . METHODS This was a double-masked , placebo-controlled ( sham treatment ) , r and omized , multicenter clinical trial involving 28 ophthalmology practice s in Europe and North America . The study population was patients with age-related macular degeneration , with subfoveal choroidal neovascularization lesions measuring no greater than 5400 microm in greatest linear dimension with either 1 ) occult with no classic choroidal neovascularization , best-corrected visual acuity score of at least 50 ( Snellen equivalent approximately 20/100 ) , and evidence of hemorrhage or recent disease progression ; or 2 ) evidence of classic choroidal neovascularization with a best-corrected visual acuity score of at least 70 ( better than a Snellen equivalent of approximately 20/40 ) ; assigned r and omly ( 2:1 ) to verteporfin therapy or placebo therapy . Verteporfin ( 6 mg per square meter of body surface area ) or placebo ( 5 % dextrose in water ) was administered by means of intravenous infusion of 30 ml over 10 minutes . Fifteen minutes after the start of the infusion , a laser light at 689 nm delivered 50 J/cm(2 ) by application of an intensity of 600 mW/cm(2 ) over 83 seconds using a spot size with a diameter 1000 microm larger than the greatest linear dimension of the choroidal neovascularization lesion on the retina . At follow-up examinations every 3 months , retreatment with the same regimen was applied if angiography showed fluorescein leakage . The main outcome measure was at least moderate vision loss , that is , a loss of at least 15 letters ( approximately 3 lines ) , adhering to an intent-to-treat analysis with the last observation carried forward to impute for missing data . RESULTS Two hundred ten ( 93 % ) and 193 ( 86 % ) of the 225 patients in the verteporfin group compared with 104 ( 91 % ) and 99 ( 87 % ) of the 114 patients in the placebo group completed the month 12 and 24 examinations , respectively . On average , verteporfin-treated patients received five treatments over the 24 months of follow-up . The primary outcome was similar for the verteporfin-treated and the placebo-treated eyes through the month 12 examination , although a number of secondary visual and angiographic outcomes significantly favored the verteporfin-treated group . Between the month 12 and 24 examinations , the treatment benefit grew so that by the month 24 examination , the verteporfin-treated eyes were less likely to have moderate or severe vision loss . Of the 225 verteporfin-treated patients , 121 ( 54 % ) compared with 76 ( 67 % ) of 114 placebo-treated patients lost at least 15 letters ( P = .023 ) . Likewise , 67 of the verteporfin-treated patients ( 30 % ) compared with 54 of the placebo-treated patients ( 47 % ) lost at least 30 letters ( P = .001 ) . Statistically significant results favoring verteporfin therapy at the month 24 examination were consistent between the total population and the subgroup of patients with a baseline lesion composition identified as occult choroidal neovascularization with no classic choroidal neovascularization . This subgroup included 166 of the 225 verteporfin-treated patients ( 74 % ) and 92 of the 114 placebo-treated patients ( 81 % ) . In these patients , 91 of the verteporfin-treated group ( 55 % ) compared with 63 of the placebo-treated group ( 68 % ) lost at least 15 letters ( P = .032 ) , whereas 48 of the verteporfin-treated group ( 29 % ) and 43 of the placebo-treated group ( 47 % ) lost at least 30 letters ( P = .004 ) . Other secondary outcomes , including visual acuity letter score worse than 34 ( approximate Snellen equivalent of 20/200 or worse ) , mean change in visual acuity letter score , development of classic choroidal neovascularization , progression of classic choroidal neovascularization and size of lesion , favored the verteporfin-treated group at both the month 12 and month 24 examination for both the entire study group and the subgroup of cases with occult with no classic choroidal neovascularization at baseline . Subgroup analyses of lesions composed of occult with no classic choroidal neovascularization at baseline suggested that the treatment benefit was greater for patients with either smaller lesions ( 4 disc areas or less ) or lower levels of visual acuity ( letter score less than 65 , an approximate Snellen equivalent of 20/50(-1 ) or worse ) at baseline . Prospect ively planned multivariable analyses confirmed that these two baseline variables affected the magnitude of treatment benefit . ( ABSTRACT TRUNCATED OBJECTIVE To report 24-month vision and fluorescein angiographic outcomes from trials evaluating photodynamic therapy with verteporfin ( Visudyne ; CIBA Vision Corp , Duluth , Ga ) in patients with subfoveal choroidal neovascularization ( CNV ) caused by age-related macular degeneration ( AMD ) . DESIGN Two multicenter , double-masked , placebo-controlled , r and omized clinical trials . SETTING Twenty-two ophthalmology practice s in Europe and North America . PARTICIPANTS Patients with subfoveal CNV lesions caused by AMD with greatest linear dimension on the retina measuring 5400 micrometer or less , with evidence of classic CNV and best-corrected visual acuity ( approximate Snellen equivalent ) between 20/40 and 20/200 . METHODS The methods were similar to those described in our 1-year results , with follow-up examinations beyond 1 year continuing every 3 months ( except for Photograph Reading Center evaluations , which occurred only at month 18 and month 24 examinations ) . During the second year , the same regimen ( with verteporfin or placebo as applied at baseline ) was used if angiography showed fluorescein leakage from CNV . The primary outcome was the proportion of eyes with fewer than 15 letters ( approximately 3 lines ) of visual acuity loss at the month 24 examination , adhering to an intent-to-treat analysis . The last observation was carried forward to impute for any missing data . RESULTS Three hundred fifty-one ( 87 % ) of 402 patients in the verteporfin group compared with 178 ( 86 % ) of 207 patients in the placebo group completed the month 24 examination . Beneficial outcomes with respect to visual acuity and contrast sensitivity noted at the month 12 examination in verteporfin-treated patients were sustained through the month 24 examination . At the month 24 examination for the primary outcome , 213 ( 53 % ) of 402 verteporfin-treated patients compared with 78 ( 38 % ) of 207 placebo-treated patients lost fewer than 15 letters ( P<.001 ) . In subgroup analyses for predominantly classic lesions ( in which the area of classic CNV makes up at least 50 % of the area of the entire lesion ) at baseline , 94 ( 59 % ) of 159 verteporfin-treated patients compared with 26 ( 31 % ) of 83 placebo-treated patients lost fewer than 15 letters at the month 24 examination ( P<.001 ) . For minimally classic lesions ( in which the area of classic CNV makes up < 50 % but > 0 % of the area of the entire lesion ) at baseline , no statistically significant differences in visual acuity were noted . Few additional photosensitivity adverse reactions and injection site adverse events were associated with verteporfin therapy in the second year of follow-up . CONCLUSIONS The visual acuity benefits of verteporfin therapy for AMD patients with predominantly classic CNV subfoveal lesions are safely sustained for 2 years , providing more compelling evidence to use verteporfin therapy for these cases . For AMD patients with subfoveal lesions that are minimally classic , there is insufficient evidence to warrant routine use of verteporfin therapy OBJECTIVE To report vision and safety outcomes from an extension of a 2-year investigation evaluating verteporfin photodynamic therapy in patients with age-related macular degeneration with subfoveal choroidal neovascularization ( CNV ) . DESIGN AND SETTING Open-label extension of selected patients from 2 multicenter , double-masked , placebo-controlled , r and omized clinical trials , the Treatment of Age-Related Macular Degeneration With Photodynamic Therapy ( TAP ) Investigation , at 22 ophthalmology practice s in Europe and North America . PARTICIPANTS Patients enrolled in the TAP Investigation and followed up for at least 24 months in whom verteporfin therapy to CNV might reduce the risk of further vision loss . METHODS Before receiving verteporfin therapy in the extension , eligible patients signed a written informed consent form accompanied by an oral consent process approved by local institutional review boards . Methods were similar to those described for 1- and 2-year results , with follow-up examinations beyond 2 years continuing at 3-month intervals with a few exceptions , including that extension patients with fluorescein leakage from CNV were to receive open-label verteporfin therapy irrespective of their original treatment assignment . RESULTS Of 402 patients in the verteporfin group , 351 ( 87.3 % ) completed the month 24 examination ; 320 ( 91.2 % ) of these enrolled in the extension study . The enrolled participants included 124 ( 78.0 % ) of the 159 verteporfin-treated patients with lesions composed of predominantly classic CNV at baseline , of whom 105 ( 84.7 % ) completed the month 36 examination . Verteporfin-treated patients with this lesion composition at baseline who participated in the extension study , with or without a month 36 examination , appeared more likely to have a younger age , better level of visual acuity , absence of fluorescein leakage from classic CNV , or no progression of classic CNV beyond the baseline boundaries of the lesion at the month 24 examination compared with those who did not enroll in the extension . For the 105 patients with a predominantly classic baseline lesion composition who completed the month 36 examination , an average of 1.3 treatments were given from the month 24 examination up to , but not including , the month 36 examination . A letter score loss in the study eye of at least 15 from baseline for these patients occurred in 39 ( 37.5 % ) at the month 24 examination compared with 44 ( 41.9 % ) of these patients at the month 36 examination . Visual acuity changed little from the month 24 examination ( mean , -1.9 lines ) to the month 36 examination ( mean , -2.0 lines ) for these eyes . Verteporfin-treated patients had little change in the mean visual acuity lost and few or no additional instances of infusion-related back pain or photosensitivity reactions from month 24 to month 36 . Two patients originally assigned to placebo had acute severe vision decrease within 7 days after verteporfin treatment during the extension . One patient originally assigned to verteporfin had acute severe vision decrease after verteporfin treatment of the fellow eye during the extension . CONCLUSIONS Vision outcomes for  verteporfin-treated patients with predominantly classic lesions at baseline remained relatively stable from month 24 to month 36 , although only approximately one third of the  verteporfin-treated patients originally enrolled with this lesion composition had a month 36 examination . From these results , the TAP Study Group identified no safety concerns to preclude repeating photodynamic therapy with verteporfin . Additional treatment was judged likely to reduce the risk of further vision loss . Caution appears warranted in the absence of comparison with an untreated group during the extension and since not all patients in the TAP Investigation participated in the TAP Extension OBJECTIVE To determine if photodynamic therapy with verteporfin ( Visudyne ; CIBA Vision Corp , Duluth , GA ) can improve the chance of stabilizing or improving vision ( < 8 letter loss ) safely in patients with subfoveal choroidal neovascularization ( CNV ) caused by pathologic myopia . DESIGN Multicenter , double-masked , placebo-controlled , r and omized clinical trial at 28 ophthalmology practice s in Europe and North AMERICA : PARTICIPANTS One hundred twenty patients with subfoveal CNV caused by pathologic myopia with a greatest linear dimension no more than 5400 microM and best-corrected visual acuity ( Snellen equivalent ) of approximately 20/100 or better . INTERVENTION Patients were r and omly assigned ( 2:1 ) to verteporfin ( 6 mg per square meter of body surface area ; n = 81 ) or placebo ( 5 % dextrose in water ; n = 39 ) 
    Output:
    
Subgroup analyses suggest that the benefits may be confined to people with no occult choroidal neovascularisation .
REVIEW ER 'S CONCLUSIONS Photodynamic therapy in people with classic choroidal neovascularisation due to age-related macular degeneration is effective in preventing visual loss .
There is no evidence that photodynamic therapy is beneficial for people with evidence of occult choroidal neovascularisation .