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A Hofstetter - One of the best experts on this subject based on the ideXlab platform.
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seven years experience with 5 aminolevulinic Acid in detection of transitional cell carcinoma of the bladder
Urology, 2007Co-Authors: Edwin Hungerhuber, Herbert Stepp, Martin Kriegmair, A Hofstetter, Christian G Stief, Arndt Hartmann, Ruth Knuechel, Alexander Karl, Stefan Tritschler, Dirk ZaakAbstract:Objectives Photodynamic diagnosis (PDD) using 5-Aminolevulinic Acid has proved to be a procedure with an outstanding sensitivity for the detection of transitional cell carcinoma of the bladder, in particular in the detection of flat urothelial lesions. We report on our clinical results with 875 patients (1713 PDD procedures) between March 1995 and March 2002. Methods A total of 1713 PDD procedures were done in 875 patients. Fluorescence imaging was performed 2 to 3 hours after instillation of 50 mL of a 3% solution of 5-Aminolevulinic Acid into the bladder by an incoherent light source. In total, specimens from 4630 lesions (2.7 lesions/PDD) were taken. Results In 34.8% of all biopsies, the histologic finding was malignant; 23.7% of these biopsies had been taken only because of positive fluorescence. In 28.5% of the positive biopsies, flat lesions had been identified. Also, 43.4% of carcinoma in situ and 30.7% of dysplasia II° were detected only by positive fluorescence. Of all tumor lesions, 92.0% were detected by PDD compared with 76.3% detected by white light endoscopy. Conclusions PDD has proved to be an effective detection device for superficial bladder cancer.
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transurethral resection for bladder cancer using 5 aminolevulinic Acid induced fluorescence endoscopy versus white light endoscopy
The Journal of Urology, 2002Co-Authors: Martin Kriegmair, Dirk Zaak, Karlheinz Rothenberger, Jens Rassweiler, Dieter Jocham, Ferdinand Eisenberger, Roland Tauber, A Stenzl, A HofstetterAbstract:Purpose: Endoscopy done under fluorescence induced by 5-Aminolevulinic Acid has proved to be a procedure with high sensitivity for detecting transitional cell carcinoma of the bladder. In this multicenter, parallel group, phase III study we compared 5-Aminolevulinic Acid fluorescence endoscopy guided transurethral bladder resection with transurethral bladder resection done using only white light endoscopy. The proportion of tumor-free resected cases in the 2 groups was evaluated.Materials and Methods: After patient stratification according to participating centers and European Organization for the Research and Treatment of Cancer risk score 65 and 64 were randomized to the 5-Aminolevulinic Acid fluorescence and white light endoscopy groups, respectively. Residual tumor was evaluated in the 2 groups by repeat transurethral resection 10 to 14 days later. Analysis was performed according to the intent to treat principle with all patients randomized, followed by per protocol analysis.Results: Intent to treat ...
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detection of early bladder cancer by 5 aminolevulinic Acid induced porphyrin fluorescence
The Journal of Urology, 1996Co-Authors: Martin Kriegmair, Herbert Stepp, Ferdinand Hofstädter, R. Knüchel, R Baumgartner, A HofstetterAbstract:AbstractPurpose: We determined whether the sensitivity of detecting dysplasia or early bladder cancer can be improved by 5-Aminolevulinic Acid induced porphyrin fluorescence.Materials and Methods: A 3 percent 5-Aminolevulinic Acid solution was instilled intravesically before cystoscopy in 104 patients. The 5-Aminolevulinic Acid induced porphyrin fluorescence was excited by violet light from a krypton ion laser (wavelength 406.7 nm.).Results: The sensitivity of the fluorescence cystoscopy (96.9 percent) was significantly (p less than 0.0001) greater than that of white light cystoscopy (72.7 percent). There was no impact on specificity.Conclusions: Due to the high sensitivity of the procedure fluorescence guided biopsies are recommended instead of random biopsies.
Martin Kriegmair - One of the best experts on this subject based on the ideXlab platform.
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seven years experience with 5 aminolevulinic Acid in detection of transitional cell carcinoma of the bladder
Urology, 2007Co-Authors: Edwin Hungerhuber, Herbert Stepp, Martin Kriegmair, A Hofstetter, Christian G Stief, Arndt Hartmann, Ruth Knuechel, Alexander Karl, Stefan Tritschler, Dirk ZaakAbstract:Objectives Photodynamic diagnosis (PDD) using 5-Aminolevulinic Acid has proved to be a procedure with an outstanding sensitivity for the detection of transitional cell carcinoma of the bladder, in particular in the detection of flat urothelial lesions. We report on our clinical results with 875 patients (1713 PDD procedures) between March 1995 and March 2002. Methods A total of 1713 PDD procedures were done in 875 patients. Fluorescence imaging was performed 2 to 3 hours after instillation of 50 mL of a 3% solution of 5-Aminolevulinic Acid into the bladder by an incoherent light source. In total, specimens from 4630 lesions (2.7 lesions/PDD) were taken. Results In 34.8% of all biopsies, the histologic finding was malignant; 23.7% of these biopsies had been taken only because of positive fluorescence. In 28.5% of the positive biopsies, flat lesions had been identified. Also, 43.4% of carcinoma in situ and 30.7% of dysplasia II° were detected only by positive fluorescence. Of all tumor lesions, 92.0% were detected by PDD compared with 76.3% detected by white light endoscopy. Conclusions PDD has proved to be an effective detection device for superficial bladder cancer.
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transurethral resection for bladder cancer using 5 aminolevulinic Acid induced fluorescence endoscopy versus white light endoscopy
The Journal of Urology, 2002Co-Authors: Martin Kriegmair, Dirk Zaak, Karlheinz Rothenberger, Jens Rassweiler, Dieter Jocham, Ferdinand Eisenberger, Roland Tauber, A Stenzl, A HofstetterAbstract:Purpose: Endoscopy done under fluorescence induced by 5-Aminolevulinic Acid has proved to be a procedure with high sensitivity for detecting transitional cell carcinoma of the bladder. In this multicenter, parallel group, phase III study we compared 5-Aminolevulinic Acid fluorescence endoscopy guided transurethral bladder resection with transurethral bladder resection done using only white light endoscopy. The proportion of tumor-free resected cases in the 2 groups was evaluated.Materials and Methods: After patient stratification according to participating centers and European Organization for the Research and Treatment of Cancer risk score 65 and 64 were randomized to the 5-Aminolevulinic Acid fluorescence and white light endoscopy groups, respectively. Residual tumor was evaluated in the 2 groups by repeat transurethral resection 10 to 14 days later. Analysis was performed according to the intent to treat principle with all patients randomized, followed by per protocol analysis.Results: Intent to treat ...
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clinical experience with 5 aminolevulinic Acid and photodynamic therapy for refractory superficial bladder cancer
The Journal of Urology, 2001Co-Authors: Raphaela Waidelich, Herbert Stepp, Reinhold Baumgartner, Ernst Weninger, Alfons Hofstetter, Martin KriegmairAbstract:Purpose: We determined whether photodynamic therapy after the oral administration of 5-Aminolevulinic Acid in patients with superficial bladder cancer that cannot be controlled by transurethral resection and intravesical bacillus Calmette-Guerin (BCG) immunotherapy would preserve the bladder, while stopping tumor progression. Side effects of treatment were also assessed.Materials and Methods: We performed photodynamic therapy after the oral administration of 5-Aminolevulinic Acid in 24 patients with rapidly recurring, multifocal, BCG refractory superficial pTa-pT1 transitional cell carcinoma of the bladder and carcinoma in situ.Results: At a median followup of 36 months (range 12 to 51) 3 of the 5 patients with carcinoma in situ and 4 of the 19 with papillary tumors were free of recurrence. Three patients were rendered disease-free by repeat photodynamic therapy with 5-Aminolevulinic Acid and 3 underwent cystectomy. Tumor progression was stopped in 20 of our 24 cases. Immediately after the oral administra...
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detection of early bladder cancer by 5 aminolevulinic Acid induced porphyrin fluorescence
The Journal of Urology, 1996Co-Authors: Martin Kriegmair, Herbert Stepp, Ferdinand Hofstädter, R. Knüchel, R Baumgartner, A HofstetterAbstract:AbstractPurpose: We determined whether the sensitivity of detecting dysplasia or early bladder cancer can be improved by 5-Aminolevulinic Acid induced porphyrin fluorescence.Materials and Methods: A 3 percent 5-Aminolevulinic Acid solution was instilled intravesically before cystoscopy in 104 patients. The 5-Aminolevulinic Acid induced porphyrin fluorescence was excited by violet light from a krypton ion laser (wavelength 406.7 nm.).Results: The sensitivity of the fluorescence cystoscopy (96.9 percent) was significantly (p less than 0.0001) greater than that of white light cystoscopy (72.7 percent). There was no impact on specificity.Conclusions: Due to the high sensitivity of the procedure fluorescence guided biopsies are recommended instead of random biopsies.
Robert F Spetzler - One of the best experts on this subject based on the ideXlab platform.
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intraoperative confocal microscopy in the visualization of 5 aminolevulinic Acid fluorescence in low grade gliomas
Journal of Neurosurgery, 2011Co-Authors: Nader Sanai, Laura A Snyder, Norissa Honea, Stephen W Coons, Jennifer Eschbacher, Kris A Smith, Robert F SpetzlerAbstract:Object Greater extent of resection (EOR) for patients with low-grade glioma (LGG) corresponds with improved clinical outcome, yet remains a central challenge to the neurosurgical oncologist. Although 5-Aminolevulinic Acid (5-ALA)–induced tumor fluorescence is a strategy that can improve EOR in gliomas, only glioblastomas routinely fluoresce following 5-ALA administration. Intraoperative confocal microscopy adapts conventional confocal technology to a handheld probe that provides real-time fluorescent imaging at up to 1000× magnification. The authors report a combined approach in which intraoperative confocal microscopy is used to visualize 5-ALA tumor fluorescence in LGGs during the course of microsurgical resection. Methods Following 5-ALA administration, patients with newly diagnosed LGG underwent microsurgical resection. Intraoperative confocal microscopy was conducted at the following points: 1) initial encounter with the tumor; 2) the midpoint of tumor resection; and 3) the presumed brain-tumor inter...
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intraoperative confocal microscopy in the visualization of 5 aminolevulinic Acid fluorescence in low grade gliomas
Journal of Neurosurgery, 2011Co-Authors: Nader Sanai, Laura A Snyder, Norissa Honea, Stephen W Coons, Jennifer Eschbacher, Kris A Smith, Robert F SpetzlerAbstract:Object Greater extent of resection (EOR) for patients with low-grade glioma (LGG) corresponds with improved clinical outcome, yet remains a central challenge to the neurosurgical oncologist. Although 5-Aminolevulinic Acid (5-ALA)–induced tumor fluorescence is a strategy that can improve EOR in gliomas, only glioblastomas routinely fluoresce following 5-ALA administration. Intraoperative confocal microscopy adapts conventional confocal technology to a handheld probe that provides real-time fluorescent imaging at up to 1000× magnification. The authors report a combined approach in which intraoperative confocal microscopy is used to visualize 5-ALA tumor fluorescence in LGGs during the course of microsurgical resection. Methods Following 5-ALA administration, patients with newly diagnosed LGG underwent microsurgical resection. Intraoperative confocal microscopy was conducted at the following points: 1) initial encounter with the tumor; 2) the midpoint of tumor resection; and 3) the presumed brain-tumor inter...
Georg Widhalm - One of the best experts on this subject based on the ideXlab platform.
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surgical microscope with integrated fluorescence lifetime imaging for 5 aminolevulinic Acid fluorescence guided neurosurgery
Journal of Biomedical Optics, 2020Co-Authors: Mikael T Erkkila, David Reichert, Nancy Heckerdenschlag, Marco Wilzbach, Christoph Hauger, Rainer A Leitgeb, Johanna Gesperger, Barbara Kiesel, Thomas Roetzer, Georg WidhalmAbstract:Significance: 5-Aminolevulinic Acid (5-ALA)-based fluorescence guidance in conventional neurosurgical microscopes is limited to strongly fluorescent tumor tissue. Therefore, more sensitive, intrasurgical 5-ALA fluorescence visualization is needed. Aim: Macroscopic fluorescence lifetime imaging (FLIM) was performed ex vivo on 5-ALA-labeled human glioma tissue through a surgical microscope to evaluate its feasibility and to compare it to fluorescence intensity imaging. Approach: Frequency-domain FLIM was integrated into a surgical microscope, which enabled parallel wide-field white-light and fluorescence imaging. We first characterized our system and performed imaging of two samples of suspected low-grade glioma, which were compared to histopathology. Results: Our imaging system enabled macroscopic FLIM of a 6.5 × 6.5 mm2 field of view at spatial resolutions <20 μm. A frame of 512 × 512 pixels with a lifetime accuracy <1 ns was obtained in 65 s. Compared to conventional fluorescence imaging, FLIM considerably highlighted areas with weak 5-ALA fluorescence, which was in good agreement with histopathology. Conclusions: Integration of macroscopic FLIM into a surgical microscope is feasible and a promising method for improved tumor delineation.
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5 aminolevulinic Acid induced protoporphyrin ix ala ppix fluorescence guidance in meningioma surgery
Journal of Neuro-oncology, 2019Co-Authors: Pablo A Valdes, Georg Widhalm, Matthias Millesi, David W RobertsAbstract:5-Aminolevulinic Acid induced protoporphyrin IX (5-ALA-PpIX) fluorescence guidance has emerged as a valuable surgical adjunct for resection of intracranial tumors. Here we present a focused review on 5-ALA-PpIX fluorescence guidance for meningiomas. We discuss the clinical studies and specific applications to date as well as the two main intraoperative fluorescence technologies applied to meningiomas. The use of 5-ALA-PpIX in meningiomas holds promising potential so neurosurgeons can improve surgical outcomes for patients with meningiomas as well as be pioneers in developing improved fluorescence imaging technologies.
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analysis of 5 aminolevulinic Acid induced fluorescence in 55 different spinal tumors
Neurosurgical Focus, 2014Co-Authors: Matthias Millesi, Barbara Kiesel, Adelheid Woehrer, Johannes A Hainfellner, Klaus Novak, Mauricio Martinezmoreno, Stefan Wolfsberger, Engelbert Knosp, Georg WidhalmAbstract:Object Subtotal resection (STR) of spinal tumors can result in tumor recurrence. Currently, no clinically reliable marker is available for intraoperative visualization of spinal tumor tissue. Protoporphyrin IX (PpIX) fluorescence induced by 5-Aminolevulinic Acid (5-ALA) is capable of visualizing malignant gliomas. Fluorescence-guided resections of malignant cerebral gliomas using 5-ALA have resulted in an increased rate of complete tumor removal. Recently, the application of 5-ALA has also been described in the first cases of spinal tumors. Therefore, the aim of this observational study was to systematically investigate 5-ALA–induced fluorescence characteristics in different spinal tumor entities. Methods Three hours before the induction of anesthesia, 5-ALA was administered to patients with different intra- and extradural spinal tumors. In all patients a neurosurgical resection or biopsy of the spinal tumor was performed under conventional white-light microscopy. During each surgery, the presence of PpIX...
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5 aminolevulinic Acid induced fluorescence is a powerful intraoperative marker for precise histopathological grading of gliomas with non significant contrast enhancement
PLOS ONE, 2013Co-Authors: Georg Widhalm, Barbara Kiesel, Adelheid Woehrer, Johannes A Hainfellner, Engelbert Knosp, Tatjana Traubweidinger, Matthias Preusser, Christine Marosi, Daniela Prayer, Stefan WolfsbergerAbstract:Background Intraoperative identification of anaplastic foci in diffusely infiltrating gliomas (DIG) with non-significant contrast-enhancement on MRI is indispensible to avoid histopathological undergrading and subsequent treatment failure. Recently, we found that 5-Aminolevulinic Acid (5-ALA) induced protoporphyrin IX (PpIX) fluorescence can visualize areas with increased proliferative and metabolic activity in such gliomas intraoperatively. As treatment of DIG is predominantely based on histopathological World Health Organisation (WHO) parameters, we analyzed whether PpIX fluorescence can detect anaplastic foci according to these criteria.
Herbert Stepp - One of the best experts on this subject based on the ideXlab platform.
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seven years experience with 5 aminolevulinic Acid in detection of transitional cell carcinoma of the bladder
Urology, 2007Co-Authors: Edwin Hungerhuber, Herbert Stepp, Martin Kriegmair, A Hofstetter, Christian G Stief, Arndt Hartmann, Ruth Knuechel, Alexander Karl, Stefan Tritschler, Dirk ZaakAbstract:Objectives Photodynamic diagnosis (PDD) using 5-Aminolevulinic Acid has proved to be a procedure with an outstanding sensitivity for the detection of transitional cell carcinoma of the bladder, in particular in the detection of flat urothelial lesions. We report on our clinical results with 875 patients (1713 PDD procedures) between March 1995 and March 2002. Methods A total of 1713 PDD procedures were done in 875 patients. Fluorescence imaging was performed 2 to 3 hours after instillation of 50 mL of a 3% solution of 5-Aminolevulinic Acid into the bladder by an incoherent light source. In total, specimens from 4630 lesions (2.7 lesions/PDD) were taken. Results In 34.8% of all biopsies, the histologic finding was malignant; 23.7% of these biopsies had been taken only because of positive fluorescence. In 28.5% of the positive biopsies, flat lesions had been identified. Also, 43.4% of carcinoma in situ and 30.7% of dysplasia II° were detected only by positive fluorescence. Of all tumor lesions, 92.0% were detected by PDD compared with 76.3% detected by white light endoscopy. Conclusions PDD has proved to be an effective detection device for superficial bladder cancer.
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role of 5 aminolevulinic Acid in the detection of urothelial premalignant lesions
Cancer, 2002Co-Authors: M Dirk D Zaak, Herbert Stepp, M Edwin D Hungerhuber, M Peter D Schneede, M Dominic D Frimberger, M Stefan D Corvin, M Nikolaus D Schmeller, M Kriegmair, M Alfons D Hofstetter, M Ruth D KnochelAbstract:BACKGROUND The authors evaluated the role of 5-Aminolevulinic Acid (5-ALA)-induced fluorescence endoscopy (AFE) in the detection of flat urothelial lesions in light of the suggestions made for flat neoplastic lesions within the 1999 World Health Organization (WHO) classification of urinary bladder tumors. METHODS From 1995 to 2000, 713 patients underwent 1414 AFE procedures for the detection of transitional cell carcinoma of the bladder (TCCB). Fluorescence imaging was performed with an incoherent light source (D-light; 380–440 nm) that was filtered for efficient protoporphyrin IX excitation and with cystoscopes partially blocking reflected excitation light to enable fluorescence evaluation by a red/blue color contrast 2–3 hours after 50 mL of a 3% solution of 5-ALA was instilled into the bladder. In total, 3834 biopsy specimens (mean, 2.7 specimens per AFE procedure) were taken. RESULTS Malignant disease was found in 1250 (32.6%) of all biopsies, with 304 biopsies (24.3%) showing carcinoma in situ (cis) and dysplasia II° (dys II) according to the previous diagnostic criteria of the WHO. Under prior conventional white-light endoscopy, 30.3% of specimens with dys II and 52.8% of specimens with cis had been missed. CONCLUSIONS The current results suggest that 5-ALA may be more effective in the detection of flat urothelial lesions than the current diagnostic devices. Cancer 2002;95:1234–8. © 2002 American Cancer Society. DOI 10.1002/cncr.10821
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clinical experience with 5 aminolevulinic Acid and photodynamic therapy for refractory superficial bladder cancer
The Journal of Urology, 2001Co-Authors: Raphaela Waidelich, Herbert Stepp, Reinhold Baumgartner, Ernst Weninger, Alfons Hofstetter, Martin KriegmairAbstract:Purpose: We determined whether photodynamic therapy after the oral administration of 5-Aminolevulinic Acid in patients with superficial bladder cancer that cannot be controlled by transurethral resection and intravesical bacillus Calmette-Guerin (BCG) immunotherapy would preserve the bladder, while stopping tumor progression. Side effects of treatment were also assessed.Materials and Methods: We performed photodynamic therapy after the oral administration of 5-Aminolevulinic Acid in 24 patients with rapidly recurring, multifocal, BCG refractory superficial pTa-pT1 transitional cell carcinoma of the bladder and carcinoma in situ.Results: At a median followup of 36 months (range 12 to 51) 3 of the 5 patients with carcinoma in situ and 4 of the 19 with papillary tumors were free of recurrence. Three patients were rendered disease-free by repeat photodynamic therapy with 5-Aminolevulinic Acid and 3 underwent cystectomy. Tumor progression was stopped in 20 of our 24 cases. Immediately after the oral administra...
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photodynamic therapy of vulvar intraepithelial neoplasia using 5 aminolevulinic Acid
International Journal of Cancer, 2000Co-Authors: Peter Hillemanns, Herbert Stepp, Reinhold Baumgartner, Michael Untch, Florian Prove, Christian Dannecker, Joachim Diebold, Helmut Weingandt, Matthias KorellAbstract:Photodynamic (PDT) therapy is a relatively new technique with unique properties that make it attractive for the local treatment of superficial epithelial disorders. The objective of this study was to investigate the clinical response of PDT with the photosensitizing agent 5-Aminolevulinic Acid (5-ALA) in patients with vulvar intraepithelial neoplasia (VIN) grades 1 to 3. Twenty-five patients with 111 lesions of VIN 1–3 were topically sensitized with 10 ml of a 20% solution of 5-ALA and treated with 57 cycles of laser light at 635 nm (100 J/cm2). Seventy (64%) of the 111 VIN lesions regressed after various PDT cycles. A complete response was achieved in 13 patients (52%) with 27 lesions. All patients with VIN 1 and mono- and bifocal VIN 2–3 showed complete clearance. However, a complete response could be achieved in only 4 (27%) of 15 women with multifocal VIN 2–3, whereas a partial response was noted in 9 of these patients with a total of 70 lesions, out of which 44 (63%) lesions disappeared. No response was seen in 2 patients with multifocal VIN 3. Histological assessment of the fluorescence-directed biopsies revealed that increased pigmentation and hyperkeratosis of the lesions were associated with low response rates. PDT using 5-ALA represents an alternative treatment modality for VIN which is easy to perform and has the advantage of minimal tissue destruction, low side effects and excellent cosmetic results. However, multifocal VIN disease with pigmented and hyperkeratinic lesions remains difficult to treat. Int. J. Cancer 85:649–653, 2000. © 2000 Wiley-Liss, Inc.
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intraoperative detection of malignant gliomas by 5 aminolevulinic Acid induced porphyrin fluorescence
Neurosurgery, 1998Co-Authors: W Stummer, Alwin E. Goetz, Herbert Stepp, Susanne Stocker, Simon Wagner, Clemens Fritsch, Claudia Goetz, Rainer Kiefmann, Hans J ReulenAbstract:Objective Survival after surgery and radiotherapy for the treatment of malignant gliomas is linked to the completeness of tumor removal. Therefore, methods that permit intraoperative identification of residual tumor tissue may be of benefit. In a preliminary investigation, we have studied the value of fluorescent porphyrins that accumulate in malignant tissue after administration of a precursor (5-Aminolevulinic Acid) for labeling of malignant gliomas in nine patients. Methods Three hours before the induction of anesthesia, 10 mg 5-Aminolevulinic Acid/kg body weight was administered orally. Intraoperatively, red porphyrin fluorescence was observed with a 455-nm long-pass filter after excitation with violet-blue (375-440 nm) xenon light and was verified by analysis of fluorescence spectra. Fluorescing and nonfluorescing samples taken from the tumor perimeters were examined histologically or used to study the photobleaching of porphyrins by excitation light and white light from the operating microscope. Plasma and erythrocyte porphyrin levels were determined by fluorescence photometry. Results Normal brain tissue revealed no porphyrin fluorescence, whereas tumor tissue was distinguished by bright red fluorescence. For a total of 89 tissue biopsies, sensitivity was 85% and specificity was 100% for the detection of malignant tissue. For seven of nine patients, visible porphyrin fluorescence led to further resection of the tumor. Under operating light conditions, fluorescence decayed to 36% in 25 minutes for violet-blue light and in 87 minutes for white light. Plasma and erythrocyte porphyrin contents increased slightly, without exceeding normal levels. Conclusion Our observations suggest that 5-Aminolevulinic Acid-induced porphyrin fluorescence may label malignant gliomas safely and accurately enough to enhance the completeness of tumor removal.
