***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 
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    ***EXAMPLES*** 
    Input: BACKGROUND 5-Aminolevulinic acid is a non-fluorescent prodrug that leads to intracellular accumulation of fluorescent porphyrins in malignant gliomas-a finding that is under investigation for intraoperative identification and resection of these tumours . We aim ed to assess the effect of fluorescence-guided resection with 5-aminolevulinic acid on surgical radicality , progression-free survival , overall survival , and morbidity . METHODS 322 patients aged 23 - 73 years with suspected malignant glioma amenable to complete resection of contrast-enhancing tumour were r and omly assigned to 20 mg/kg bodyweight 5-aminolevulinic acid for fluorescence-guided resection ( n=161 ) or to conventional microsurgery with white light ( n=161 ) . The primary endpoints were the number of patients without contrast-enhancing tumour on early MRI ( ie , that obtained within 72 h after surgery ) and 6-month progression-free survival as assessed by MRI . Secondary endpoints were volume of residual tumour on postoperative MRI , overall survival , neurological deficit , and toxic effects . We report the results of an interim analysis with 270 patients in the full- analysis population ( 139 assigned 5-aminolevulinic acid , 131 assigned white light )  , which excluded patients with ineligible histological and radiological findings as assessed by central review ers who were masked as to treatment allocation ; the interim analysis result ed in termination of the study as defined by the protocol . Primary and secondary endpoints were analysed by intention to treat in the full- analysis population . The study is registered at http://www . clinical trials.gov as NCT00241670 . FINDINGS Median follow-up was 35.4 months ( 95 % CI 1.0 - 56.7 ) . Contrast-enhancing tumour was resected completely in 90 ( 65 % ) of 139 patients assigned 5-aminolevulinic acid compared with 47 ( 36 % ) of 131 assigned white light ( difference between groups 29 % [ 95 % CI 17 - 40 ] , p<0.0001 ) . Patients allocated 5-aminolevulinic acid had higher 6-month progression free survival than did those allocated white light ( 41.0 % [ 32.8 - 49.2 ] vs 21.1 % [ 14.0 - 28.2 ] ; difference between groups 19.9 % [ 9.1 - 30.7 ] , p=0.0003 , Z test ) . Groups did not differ in the frequency of severe adverse events or adverse events in any organ system class reported within 7 days after surgery . INTERPRETATION Tumour fluorescence derived from 5-aminolevulinic acid enables more complete resections of contrast-enhancing tumour , leading to improved progression-free survival in patients with malignant glioma We have evaluated the influence of fluorescein-guided resection on gross total resection ( GTR ) and survival in a series of patients with GBM . Group 1 consisted of 47 patients given fluorescein and group 2 comprised 33 patients , on whom fluorescein was not used .  Median survival time was 43.9 weeks in the patients given fluorescein and was 41.8 weeks in the non-fluorescein group . There was no statistically significant difference in survival between the two groups . However , the extent of resection had a powerful influence on the median survival time . Survival was 34.3 weeks after partial resection and 46.5 after GTR . Our data shows that the use of fluorescein injection is a simple procedure , which allows a significant increase in the number of patients having GTR ( 83 vs. 55 % ) . Our findings are similar to a recently published multicentre Phase III r and omized trial in which 5-aminolevulinic acid was used to facilitate resection of malignant glioma BACKGROUND Intraoperative MRI is increasingly used in neurosurgery , although there is little evidence for its use . We aim ed to assess efficacy of intraoperative MRI guidance on extent of resection in patients with glioma . METHODS In our prospect i ve , r and omised , parallel-group trial , we enrolled adults ( ≥18 years ) with contrast enhancing gliomas amenable to radiologically complete resection who presented to Goethe University ( Frankfurt , Germany ) . We r and omly assigned patients ( 1:1 ) with computer-generated blocks of four and a sealed-envelope design to undergo intraoperative MRI-guided surgery or conventional microsurgery ( control group ) . Surgeons and patients were unmasked to treatment group allocation , but an independent neuroradiologist was masked during analysis of all preoperative and postoperative imaging data . The primary endpoint was rate of complete resections as established by early postoperative high-field MRI ( 1·5 T or 3·0 T ) . Analysis was done per protocol . This study is registered with Clinical Trials.gov , number NCT01394692 . FINDINGS We enrolled 58 patients between Oct 1 , 2007 , and July 1 , 2010 . 24 ( 83 % ) of 29 patients r and omly allocated to the intraoperative MRI group and 25 ( 86 % ) of 29 controls were eligible for analysis ( four patients in each group had metastasis and one patient in the intraoperative MRI group withdrew consent after r and omisation ) . More patients in the intraoperative MRI group had complete tumour resection ( 23 [ 96 % ] of 24 patients ) than did in the control group ( 17 [ 68 % ] of 25 , p=0·023 ) . Postoperative rates of new neurological deficits did not differ between patients in the intraoperative MRI group ( three [ 13 % ] of 24 ) and controls ( two [ 8 % ] of 25 , p=1·0 ) . No patient for whom use of intraoperative MRI led to continued resection of residual tumour had neurological deterioration . One patient in the control group died before 6 months . INTERPRETATION Our study provides evidence for the use of intraoperative MRI guidance in glioma surgery : such imaging helps surgeons provide the optimum extent of resection . FUNDING None OBJECT Accumulating data suggest more aggressive surgery in patients with malignant glioma to improve outcome . However , extended surgery may increase morbidity . The r and omized Phase III 5-aminolevulinic acid ( ALA ) study investigated 5-ALA-induced fluorescence as a tool for improving resections . An interim analysis demonstrated more frequent complete resections with longer progression-free survival ( PFS ) . However , marginal differences were found regarding neurological deterioration and the frequency of additional therapies . Presently , the authors focus on the latter aspects in the final study population , and attempt to determine how safety might be affected by cytoreductive surgery . METHODS Patients with malignant gliomas were r and omized for fluorescence-guided ( ALA group ) or conventional white light ( WL ) ( WL group ) microsurgery .  The final intent-to-treat population consisted of 176 patients in the ALA and 173 in the WL group . Primary efficacy variables were contrast-enhancing tumor on early MR imaging and 6-month PFS . Among secondary outcome measures , the National Institutes of Health Stroke Scale ( NIH-SS ) score and the Karnofsky Performance Scale ( KPS ) score were used for assessing neurological function . RESULTS More frequent complete resections and improved PFS were confirmed , with higher median residual tumor volumes in the WL group ( 0.5 vs 0 cm(3 ) , p = 0.001 ) . Patients in the ALA group had more frequent deterioration on the NIH-SS at 48 hours . Patients at risk were those with deficits unresponsive to steroids . No differences were found in the KPS score . Regarding outcome , a combined end point of risks and neurological deficits was attempted , which demonstrated results in patients in the ALA group to be superior to those in participants in the WL group . Interestingly , the cumulative incidence of repeat surgery was significantly reduced in ALA patients . When stratified by completeness of resection , patients with incomplete resections were quicker to deteriorate neurologically ( p = 0.0036 ) . CONCLUSIONS Extended resections performed using a tool such as 5-ALA-derived tumor fluorescence , carries the risk of temporary impairment of neurological function . However , risks are higher in patients with deficits unresponsive to steroids Glioblastoma multiforme ( GBM ) carries dismal prognosis and can not be eradicated surgically because of its wide brain invasion . The objective of this prospect i ve r and omised controlled trial was to evaluate ALA and Photofrin ® fluorescence-guided resection ( FGR ) and repetitive photodynamic therapy ( PDT ) in GBM . We recruited 27 patients ; 13 were in the study group and 14 were in the control group . The mean survival of the study group was 52.8 weeks compared to 24.6 weeks in the control group ( p < 0.01 ) . The study group gained on average 20 points on the Karnofsky performance score ( p < 0.05 ) . There were no differences in complications or hospital stay between the two groups . The mean time to tumour progression was 8.6 months in the study group compared to 4.8 months in the control group ( p < 0.05 ) . Therefore , ALA and Photofrin ® fluorescence-guided resection and repetitive PDT offered a worthwhile survival advantage without added risk to patients with GBM . A multicentre r and omized controlled trial is warranted to confirm these results The first study of photodynamic therapy in the human gastrointestinal tract using 5 aminolaevulinic acid ( ALA ) induced protoporphyrin IX as the photosensitising agent is described . Eighteen patients with colorectal , duodenal , and oesophageal tumours were studied . After 30 - 60 mg/kg of ALA given orally , biopsy specimens of tumour and adjacent normal mucosa were taken 1 - 72 hours later . These specimens were examined by quantitative fluorescence microscopy for assessment of sensitisation with protoporphyrin IX .  Ten patients were given a second dose of ALA a few weeks later and their tumours were treated with red laser light ( 628 nm ) . With 30 mg/kg ALA , the highest fluorescence values were detected in the duodenum and oesophagus , and the lowest in the large bowel . Doubling the ALA dose in patients with colorectal tumours gave protoporphyrin IX fluorescence intensities similar to those in patients with upper gastrointestinal lesions and improved the tumour : normal mucosa protoporphyrin IX sensitisation ratio . The treated patients showed superficial mucosal necrosis in the areas exposed to laser light . Six patients had transient rises in serum aspartate aminotransferases , two mild skin photosensitivity reactions , and five mild nausea and vomiting . In conclusion , photodynamic therapy with systemically administered ALA may be a promising technique for the treatment of small tumours and areas of dysplasia such as in Barrett 's oesophagus OBJECTIVE To explore the role of diffusion tensor imaging ( DTI ) in neuronavigation surgery of brain tumors involving pyramidal tracts . METHODS Forty-nine patients with brain tumors involving pyramidal tracts were r and omly divided into trial group ( DTI navigation ) and control group ( traditional navigation ) . The patients in trial group underwent DTI and T1 weighted 3D navigational magnetic resonance imaging ( MRI ) studies . The main white matter tracts were constructed by the DTI data sets , and merged to the anatomical structure , which was delineated by the T1-weighted three-dimensional fast spoiled gradient recalled sequence ( 3D/FSPGR ) . The relationship between the tumors and adjacent pyramidal tracts were segmented and reconstructed for three-dimensional visualization . RESULTS In 25 patients of trial group and 24 patients of control group , the statistic analysis confirmed well balance of main variations . The tumors were completely resected in 12 patients ( 50.0 % ) of control group and in 20 patients ( 80.0 % ) of trial group ( P < 0.05 ) . Postoperative aggravated contralateral extremities weakness or hemiplegia due to pyramidal tract injury occurring in 75.0 % cases of control group whereas only 20.0 % patients in trial group ( P < 0.01 ) . The mean Karnofsky scale were 69.58 + /- 23.49 and 84.80 + /- 23.49 respectively in control and trial groups ( P < 0.05 ) . The excellent outcome ratio ( Karnofsky scale = 90 - 100 ) was 37.5 % in control group and 72.0 % in trial group respectively ( P < 0.05 ) . CONCLUSIONS DTI allows individual estimation of large fiber tracts of brain . Furthermore , to integrate spatial three-dimensional information concerning the white matter tracts into traditional neuronavigation images during surgery , was valuable in presenting topographical character of involving ( shift or erosive ) pyramidal tracts and relationship with the margins of neighboring tumors . The mapping of large fiber tracts was a safe , efficient , reliable technique . DTI should be routinely used in neuronavigation surgery of brain tumor involving pyramidal tracts to plan the optimal trajectory and ensure total resection of the lesions during 
    Output:
    
Overall , reported events were low in most studies , but there was concern that surgical resection using 5-ALA may lead to more frequent early neurological deficits .
There is low to very low quality evidence ( according to GRADE criteria ) that image guided surgery using iMRI , 5-ALA or DTI-neuronavigation increases the proportion of patients with high grade glioma that have a complete tumour resection on post-operative MRI .
There is a theoretical concern that maximising the extent of resection may lead to more frequent adverse events but this was poorly reported in the included studies .
Effects of image guided surgery on survival and QoL are unclear .