Dr. Herbert Stepp Profile

Dr. Herbert Stepp

at LIFE-Zentrum

SPIE Involvement:

Author

Publications (57)

Proceedings Article | 13 March 2024 Presentation + Paper

Interstitial photodynamic therapy for malignant gliomas: the Munich experience

Maximilian Aumiller, Stefanie Quach, Marco Foglar, Mohamed El Fahim, Adrian Rühm, Herbert Stepp, Robert Forbrig, Niklas Thon, Ronald Sroka

Proceedings Volume 12828, 1282805 (2024) https://doi.org/10.1117/12.3002942

KEYWORDS: Tumors, Photodynamic therapy, Magnetic resonance imaging, Brain, Visible radiation, Surgery

Read Abstract +

Proceedings Article | 7 December 2021 Paper

Two-wavelength excitation spectroscopy for non-invasive detection of the iron deficiency indicator zinc protoporphyrin IX

Herbert Stepp, Christian Homann, Georg Hennig, Michael Vogeser

Proceedings Volume 11919, 119190O (2021) https://doi.org/10.1117/12.2614588

KEYWORDS: Iron, Blood, Spectroscopy, Zinc, Luminescence, Laser induced plasma spectroscopy, Tissues, Absorption, Skin, Semiconductor lasers

Read Abstract +

Proceedings Article | 7 December 2021 Paper

Investigation on treatment light transmission changes during IPDT in comparison to T1 hyperintensity in early post-therapeutic T1-weighted MRI

Maximilian Aumiller, Birgit Ertl-Wagner, Christian Heckl, Stefanie Lietke, Herbert Stepp, Ronald Sroka, Niklas Thon, Adrian Rühm

Proceedings Volume 11919, 119191O (2021) https://doi.org/10.1117/12.2614888

KEYWORDS: Magnetic resonance imaging, Absorption, Signal detection, Tumors, Photodynamic therapy, Tissue optics, Luminescence, In vitro testing, Diffusion, Data acquisition

Read Abstract +

Proceedings Article | 5 March 2021 Presentation

The enhancement of methadone on the effectiveness of 5-ALA-PDT for tumor cells

Lei Shi, Xiuli Wang, Ronald Sroka, Herbert Stepp

Proceedings Volume 11643, 116430F (2021) https://doi.org/10.1117/12.2584327

KEYWORDS: Tumors, Cell death, Photodynamic therapy, Luminescence, In vitro testing

Proceedings Article | 14 August 2019 Presentation

Interstitial photodynamic therapy (iPDT) of brain tumours (Conference Presentation)

Herbert Stepp, Adrian Rühm, Ronald Sroka, Walter Stummer

Proceedings Volume 11070, 110701Z (2019) https://doi.org/10.1117/12.2526128

KEYWORDS: Photodynamic therapy, Brain, Diffusers, Optical fibers, Tumors, Luminescence, Clinical trials, Cancer, Oncology, Stem cells

Read Abstract +

Proceedings Article | 22 July 2019 Paper

Rapid spectrophotometric quantification of urinary porphyrins and porphobilinogen as screening tool for attacks of acute porphyria

C. Heckl, A. Lang, M. Vogeser, T. Stauch, C. Homann, G. Hennig, R. Sroka, H. Stepp

Proceedings Volume 11079, 110790E (2019) https://doi.org/10.1117/12.2527105

KEYWORDS: Medicine, Luminescence, Oxidation, Absorption, Absorption spectroscopy, Iodine, Algorithm development, Spectroscopy, Rhodamine, Transmittance

Read Abstract +

Proceedings Article | 22 July 2019 Paper

Individualization of interstitial photodynamic therapy for malignant gliomas

Maximilian Aumiller, Adrian Rühm, Maximilian Eisel, Christian Freymüller, Herbert Stepp, André Liemert, Alwin Kienle, Ronald Sroka

Proceedings Volume 11079, 110790P (2019) https://doi.org/10.1117/12.2527115

KEYWORDS: Tissue optics, Photodynamic therapy, Geometrical optics, Signal attenuation, Brain, Integrating spheres, Tissues, Absorption, Scattering, Liquids

Read Abstract +

SPIE Journal Paper | 24 September 2018 Open Access

Investigation of optical properties of dissected and homogenized biological tissue

Maximilian Eisel, Stephan Ströbl, Thomas Pongratz, Herbert Stepp, Adrian Rühm, Ronald Sroka

JBO, Vol. 23, Issue 09, 091418, (September 2018) https://doi.org/10.1117/12.10.1117/1.JBO.23.9.091418

KEYWORDS: Tissues, Tissue optics, Optical properties, Scattering, Lung, Absorption, Homogenization, Natural surfaces, Liver, Brain

Read Abstract +

Knowledge of tissue optical properties, in particular the absorption μa and the reduced scattering coefficient μs′, is required for diagnostic and therapeutic applications in which the light distribution during treatment has to be known. As it is generally very difficult to obtain this information with sufficient accuracy in vivo, optical properties are often approximately determined on ex vivo tissue samples. In this case, the obtained optical properties may strongly depend on the sample preparation. The extent of the expectable preparation-dependent differences was systematically investigated in comparative measurements on dissected and homogenized porcine tissue samples (liver, lung, brain, and muscle). These measurements were performed at wavelengths 520, 635, 660, and 785 nm, using a dual-step reflectance device and at a spectral range of 515 to 800 nm with an integrating sphere setup. In a third experiment, the density of tissue samples (dissected and homogenized) was investigated, as the characteristic of the packaging of internal tissue structures strongly influences the absorption and scattering. The standard errors of the obtained absorption and reduced scattering coefficients were found to be reduced in case of homogenized tissue. Homogenizing the tissues also allows a much easier and faster sample preparation, as macroscopic internal tissue structures are destroyed in the homogenized tissue so that a planar tissue sample with well-defined thickness can easily and accurately be prepared by filling the tissue paste into a cuvette. Consequently, a better reproducibility result was obtained when using homogenized samples. According to the density measurements accomplished for dissected and homogenized tissue samples, all types of tissues, except lung, showed a decrease in the density due to the homogenization process. The presented results are in good agreement for μs′ regardless of the preparation procedure, whereas μa differs, probably influenced by blood content and dehydration. Because of faster and easier preparation and easier sample positioning, homogenization prior to measurement seems to be suitable for investigating the optical properties ex vivo. Additionally, by means of using the homogenization process, the sample size and thickness do not need to be particularly large, as is the case for most biopsies from the OR.

DOWNLOAD PAPER

SPIE Journal Paper | 31 May 2018 Open Access

Rapid spectrophotometric quantification of urinary porphyrins and porphobilinogen as screening tool for attacks of acute porphyria

Alexander Lang, Christian Heckl, Michael Vogeser, Thomas Stauch, Christian Homann, Georg Hennig, Ronald Sroka, Herbert Stepp

JBO, Vol. 23, Issue 05, 055006, (May 2018) https://doi.org/10.1117/12.10.1117/1.JBO.23.5.055006

KEYWORDS: Luminescence, Oxidation, Absorption, Calibration, Iodine, Fluorescence spectroscopy, Absorption spectroscopy, Transmittance, Algorithm development, Spectroscopy

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 24 May 2018 Presentation

Investigations and developments for PDT in brain tumors (Conference Presentation)

Ronald Sroka, Adrian Rühm, Herbert Stepp, Niklas Markwardt

Proceedings Volume 10685, 1068502 (2018) https://doi.org/10.1117/12.2306925

KEYWORDS: Tissue optics, Tumors, Photodynamic therapy, Brain, Biopsy, Luminescence, Blood vessels, Integrated optics, Safety, Reliability

Read Abstract +

Proceedings Article | 29 April 2017 Paper

Photodynamic diagnosis and related optical techniques for the management of malignant glioma

R. Sroka, H. Stepp, W. Beyer, N. Markwardt, A. Rühm

Proceedings Volume 10340, 1034014 (2017) https://doi.org/10.1117/12.2270006

KEYWORDS: Tumors, Tissues, Phototherapy, Tissue optics, Luminescence, Reliability, Integrated optics, Safety

Read Abstract +

Proceedings Article | 27 April 2016 Paper

Detection limits of 405 nm and 633 nm excited PpIX fluorescence for brain tumor detection during stereotactic biopsy

Niklas Markwardt, Marcus Götz, Neda Haj-Hosseini, Bastian Hollnburger, Ronald Sroka, Herbert Stepp, Petr Zelenkov, Adrian Rühm

Proceedings Volume 9887, 98872Z (2016) https://doi.org/10.1117/12.2225234

KEYWORDS: Brain, Biopsy, Blood, Luminescence, Tissue optics, Signal detection, Ray tracing, Optical phantoms, Optical properties, Fluorescence spectroscopy, Tumors, Tissues, Liquids

Read Abstract +

Proceedings Article | 15 July 2015 Paper

Optical spectroscopy for stereotactic biopsy of brain tumors

Niklas Markwardt, Anna von Berg, Sebastian Fiedler, Marcus Goetz, Neda Haj-Hosseini, Christoph Polzer, Herbert Stepp, Petr Zelenkov, Adrian Rühm

Proceedings Volume 9542, 954208 (2015) https://doi.org/10.1117/12.2183741

KEYWORDS: Luminescence, Biopsy, Tumors, Blood, Brain, Blood vessels, Tissues, Signal detection, Capillaries, Fluorescence spectroscopy

Read Abstract +

Proceedings Article | 15 July 2015 Paper

Rapid screening test for porphyria diagnosis using fluorescence spectroscopy

A. Lang, H. Stepp, C. Homann, G. Hennig, G. Brittenham, M. Vogeser

Proceedings Volume 9537, 953706 (2015) https://doi.org/10.1117/12.2183855

KEYWORDS: Plasma, Luminescence, Blood, Fluorescence spectroscopy, Spectroscopy, Genetics, Liver, Imaging spectroscopy, Biomedical optics, Solids

Read Abstract +

Proceedings Article | 15 July 2015 Paper

In vitro study for photodynamic therapy using Fotolon in glioma treatment

Sara Abdel Hamid, Wolfgang Zimmermann, Dirk Huettenberger, Rainer Wittig, Mahmoud Abdel Kader, Herbert Stepp

Proceedings Volume 9542, 95420B (2015) https://doi.org/10.1117/12.2183884

KEYWORDS: Photodynamic therapy, Cell death, Luminescence, Beam controllers, In vitro testing, Picosecond phenomena, Cancer, Resistance, Oxygen, Fluorescence correlation spectroscopy

Read Abstract +

SPIE Journal Paper | 16 June 2015 Open Access

Medical laser application: translation into the clinics

Ronald Sroka, Herbert Stepp, Georg Hennig, Gary Brittenham, Adrian Rühm, Lothar Lilge

JBO, Vol. 20, Issue 06, 061110, (June 2015) https://doi.org/10.1117/12.10.1117/1.JBO.20.6.061110

KEYWORDS: Luminescence, Laser therapeutics, Tumors, Veins, Laser tissue interaction, Tissues, Tissue optics, Iron, Photodynamic therapy, LASIK

Read Abstract +

DOWNLOAD PAPER

Proceedings Article | 24 March 2014 Paper

5-ALA based photodynamic management of glioblastoma

Adrian Rühm, Herbert Stepp, Wolfgang Beyer, Georg Hennig, Thomas Pongratz, Ronald Sroka, Oliver Schnell, Jörg-Christian Tonn, Friedrich-Wilhelm Kreth

Proceedings Volume 8928, 89280E (2014) https://doi.org/10.1117/12.2040268

KEYWORDS: Luminescence, Optical fibers, Tumors, Photodynamic therapy, Diffusers, Spectroscopy, Biopsy, Oxygen, Fluorescence spectroscopy, Absorption

Read Abstract +

Proceedings Article | 28 February 2014 Paper

Dual-wavelength excitation to reduce background fluorescence for fluorescence spectroscopic quantitation of erythrocyte zinc protoporphyrin-IX and protoporphyrin-IX from whole blood and oral mucosa

Georg Hennig, Michael Vogeser, Lesca Holdt, Christian Homann, Michael Großmann, Herbert Stepp, Christian Gruber, Ilknur Erdogan, Stephan Hasmüller, Uwe Hasbargen, Gary Brittenham

Proceedings Volume 8951, 89510J (2014) https://doi.org/10.1117/12.2039279

KEYWORDS: Luminescence, Blood, Iron, Tissues, Fluorescence spectroscopy, Zinc, Spectroscopy, Point-of-care devices, Signal detection, Calibration

Read Abstract +

Proceedings Article | 24 June 2013 Paper

OCT assisted identification of the grade of encrustation of urologic catheters

Ronald Sroka, Michaela Püls, Herbert Stepp, Katja Zilinberg, Markus Bader, Patrick Weidlich

Proceedings Volume 8803, 88030Q (2013) https://doi.org/10.1117/12.2032031

KEYWORDS: Optical coherence tomography, Crystals, Bacteria, Imaging systems, Urinary system, Polyurethane, Statistical analysis, Tumors, Endoscopy, Biomedical optics

Read Abstract +

Introduction: Ureteric stenting is a commonly used endourologic procedure for temporary and long-term drainage of an obstructed upper urinary tract. The indication for ureteric stenting is obstruction due to intrinsic (intraureteral stones, strictures, or tumors) or extrinsic (for example compressing pelvic or retroperitoneal mass) causes. Despite the fact that stents do certainly have proven benefits in all fields of urology, there are potential morbidities. The most common problem of indwelling ureteral stents is infection. As foreign body in the urinary system, stents act as a nidus for bacteria colonization, crystallization and encrustation. Bacteria induced biofilm formation predisposes for the crystallization of lithogenic salts, such as calcium-phosphate, calcium-oxalate, magnesium-phosphate on the surface initiating stent encrustation. It was the objective of this study to evaluate whether optical coherence tomography (OCT) using both the surface and the endoluminal technique is feasible to investigate the locations and degree of encrustation process in clinically used ureteral stents. Patients and methods: After removal from patients, fourteen polyurethane JJ stents were investigated. A fresh JJ served as a control. The external surfaces were examined using an endoscopic surface OCT whereas the intraluminal surfaces were investigated by an endoluminal radial OCT device. The focus was on detection of encrustation or crystalline sedimentation. Results: In 12 female and 2 male patients, the median indwelling time of the ureteral catheter was 100 days (range 19- 217). Using the endoluminal OCT, the size and grade of intraluminal encrustation could be expressed as a percentage relating to the open lumen of the reference stent. The maximum encrustation observed resulted in a remaining unrestricted lumen of 15-35% compared to the reference. The luminal reduction caused by encrustation was significantly higher at the proximal end of the ureteral stent as compared to its distal part. The extraluminal OCT-investigations facilitated the characterization of extraluminal encrustation. Conclusion: OCT techniques were feasible and facilitated the detection of encrustation of double pigtail catheters on both the extra and intra luminal surface. Quantitative expression of the degree of intraluminal encrustation could be achieved, with the most dense and thickened occurrence of intraluminal incrustation in the upper curl of the JJ stent.

Proceedings Article | 24 June 2013 Paper

Probe-based confocal laser endomicroscopy in head and neck malignancies: early preclinical experience

Anna Englhard, Susanne Girschick, Brigitte Mack, Veronika Volgger, Oliver Gires, Christian Conderman, Herbert Stepp, Christian Stephan Betz

Proceedings Volume 8805, 880506 (2013) https://doi.org/10.1117/12.2032628

KEYWORDS: Head, Neck, Confocal microscopy, Tissues, Biopsy, Endomicroscopy, Natural surfaces, Surgery, Visualization, Endoscopy

Read Abstract +

Proceedings Article | 24 June 2013 Paper

Low dose mTHPC photodynamic therapy for cholangiocarcinoma

Herbert Stepp, Gesa Kniebühler, Thomas Pongratz, Christian Betz, Burkhard Göke, Ronald Sroka, Jörg Schirra

Proceedings Volume 8803, 88030M (2013) https://doi.org/10.1117/12.2032396

KEYWORDS: Photodynamic therapy, Luminescence, Tissues, Tumors, Skin, Endoscopy, Fluorescence spectroscopy, Spectroscopy, Bismuth, Sodium

Read Abstract +

Proceedings Article | 18 February 2012 Paper

Fluorescence guidance during stereotactic biopsy

Herbert Stepp, Wolfgang Beyer, David Brucker, Andre Ehrhardt, Stefan Fischer, Werner Goebel, Marcus Goetz, Bettina Guenther, Georg Hennig, Jochen Herms, Klaus-Martin Irion, Ann Johansson, Yvonne Kienast, Gesa Kniebuehler, Pan Li, Adrian Ruehm, Sabine Sandner

Proceedings Volume 8207, 82074H (2012) https://doi.org/10.1117/12.915751

KEYWORDS: Luminescence, Tumors, Tissues, Brain, Tissue optics, Biopsy, Blood vessels, Fluorescence spectroscopy, Capillaries, Signal detection

Read Abstract +

Proceedings Article | 8 June 2011 Paper

PD and PDT for hepatoblastoma? Preclinical considerations

Herbert Stepp, Florian Bergmann, Ann Johansson, Michael Heide, Roman Metzger, Udo Rolle, Holger Till

Proceedings Volume 8092, 80920I (2011) https://doi.org/10.1117/12.889860

KEYWORDS: Tumors, Tissues, Photodynamic therapy, Luminescence, Liver, Laparoscopy, Microscopy, Animal model studies, Optical fibers, Spectroscopy

Read Abstract +

Proceedings Article | 6 April 2011 Paper

Fluorescence and reflectance spectroscopy for protoporphyrin IX quantification in tissue-like media

Gesa Palte, Ann Johansson, Georg Hennig, Wolfgang Beyer, Herbert Stepp

Proceedings Volume 7883, 788340 (2011) https://doi.org/10.1117/12.879768

KEYWORDS: Luminescence, Tissue optics, Absorption, Scattering, Brain, Tissues, Reflectivity, Photodynamic therapy, Fluorescence spectroscopy, Optical properties

Read Abstract +

Proceedings Article | 17 May 2010 Paper

Protoporphyrin IX for photodynamic therapy of brain tumours

A. Johansson, F. Kreth, A. Ardeshiri, W. Stummer, O. Schnell, J. Herms, G. Palte, W. Beyer, H. Stepp

Proceedings Volume 7715, 77151M (2010) https://doi.org/10.1117/12.854335

KEYWORDS: Tissues, Photodynamic therapy, Brain, Luminescence, Magnetic resonance imaging, Oxygen, Fluorescence spectroscopy, Surgery, Biopsy, Semiconductor lasers

Read Abstract +

Proceedings Article | 3 March 2010 Paper

Endoscopic ICG perfusion imaging for flap transplants: technical development

Herbert Stepp, Hilmar Schachenmayr, André Ehrhardt, Werner Göbel, Sven Zhorzel, Christian Stephan Betz

Proceedings Volume 7548, 75482A (2010) https://doi.org/10.1117/12.847857

KEYWORDS: Luminescence, Cameras, Near infrared, Optical filters, Tissues, Endoscopy, Skin, LabVIEW, Head, Indocyanine green

Read Abstract +

Proceedings Article | 13 July 2009 Paper

Photodynamic management of bladder cancer

A. Johansson, H. Stepp, W. Beyer, T. Pongratz, R. Sroka, M. Bader, M. Kriegmair, D. Zaak, R. Waidelich, A. Karl, A. Hofstetter, C. Stief, R. Baumgartner

Proceedings Volume 7380, 73801S (2009) https://doi.org/10.1117/12.828315

KEYWORDS: Bladder, Photodynamic therapy, Luminescence, Cystoscopy, Bladder cancer, Tissue optics, Light sources, Backscatter, Absorption, Light

Read Abstract +

Proceedings Article | 13 July 2009 Paper

ALA-mediated fluorescence-guided resection (FGR) and PDT of glioma

Ann Johansson, Herbert Stepp, Tobias Beck, Wolfgang Beyer, Thomas Pongratz, Ronald Sroka, Thomas Meinel, Walter Stummer, Friedrich-Wilhelm Kreth, Jörg-Christian Tonn, Reinhold Baumgartner

Proceedings Volume 7380, 73801D (2009) https://doi.org/10.1117/12.822962

KEYWORDS: Photodynamic therapy, Luminescence, Tissues, Tissue optics, Brain, Semiconductor lasers, Spectroscopy, Silver, Light sources, Magnetic resonance imaging

Read Abstract +

A summary of clinical trials employing photodynamic diagnosis (PDD) and photodynamic therapy (PDT) for the diagnosis and treatment of brain malignancies is presented. Intra-cavity PDT has been performed within the surgical cavity following FGR, employing oral administration of 5-aminolevulinic acid (5-ALA), either targeting fluorescing tissue regions that were not removed during FGR due to safety reasons (referred to as focal PDT, n=20) or illuminating the entire resection cavity (referred to as integral PDT, n=9). Both approaches proved technically feasible and safe. Spectroscopic measurements performed pre-, during and post-PDT revealed Protoporphyrin IX (PpIX)-photobleaching of more than 95% after the delivery of 200 J/cm². This light dose did not induce any side effects. Furthermore, interstitial PDT (iPDT) has been employed within one feasibility trial (n=10) and one Phase I/II trial (n=15). Here, three to six cylindrical light diffusors (20-30 mm length, 200 mW/cm, 720 J/cm) were positioned within the target tissue under stereotactic guidance. Pre-treatment planning was performed with the intent to target the entire tumour volume with a sufficient light dose while also minimising the risk of any light-induced temperature increase. For the feasibility trial patients with small, recurrent gliomas were included, resulting in a median survival of 15 months as well as some unexpected longterm survivals (up to 5 years). The Phase I/II trial employed the same clinical procedures. Here, the 12-month survival was 35% and the median progression-free survival was 6 months. In summary, stereotactic iPDT in combination with treatment-planning could be shown to be a safe and feasible treatment modality. These trials are presently being extended to also include on-line monitoring of PpIX fluorescence and photobleaching kinetics. Preliminary data has revealed dramatically different PpIX levels and photobleaching kinetics. Such data could possibly be employed for realtime treatment monitoring and as an early prognostic marker for the PDT response.

Proceedings Article | 23 February 2009 Paper

A fluorescence diagnostic system detecting cancer-specific enzymatic activities: preliminary results

Tobias Beck, Herbert Stepp, Rainer Wittig, Markus Boehl, Peter Schubert, Sigrun Henkenjohann, Markus Sauer, Axel Duerkop, Christian Betz, Ann Johansson

Proceedings Volume 7169, 71691G (2009) https://doi.org/10.1117/12.812958

KEYWORDS: Luminescence, Reflectivity, Tissues, Fluorescence spectroscopy, Diagnostics, Tumors, Scattering, Optical properties, Liquids, Signal detection

Read Abstract +

Proceedings Article | 7 February 2008 Paper

Transmission of LED-light through optical fibers for optical tissue diagnostics

Simone Mitterer, Tobias Beck, André Erhardt, Christian Betz, Hilmar Schachenmayr, Herbert Stepp

Proceedings Volume 6852, 68520X (2008) https://doi.org/10.1117/12.763714

KEYWORDS: Light emitting diodes, Polymer optical fibers, Tissue optics, Fiber couplers, Optical fibers, Light sources, Ray tracing, Endoscopy, Diagnostics, Light

Read Abstract +

Proceedings Article | 11 July 2007 Paper

Multiple fluorophore-analysis (MFA) for qualitative tissue diagnosis in the oral cavity

Romana Pauli, Christian Betz, Miriam Havel, Ronald Sroka, Herbert Stepp, Andreas Leunig, Walter Assmann

Proceedings Volume 6628, 66280D (2007) https://doi.org/10.1117/12.728332

KEYWORDS: Luminescence, Tissues, Tumors, Biopsy, Head, Neck, Tissue optics, Spectroscopy, Optical filters, Tongue

Read Abstract +

Proceedings Article | 13 February 2007 Paper

Clinical pharmacokinetics of protoporphyrin IX (PpIX) in condylomata acuminata patients: ex vivo fluorescence examination

Xiu-Li Wang, Hong-Wei Wang, Zheng Huang, Herbert Stepp, Reinhold Baumgartner, Christian Dannecker, Peter Hillemanns

Proceedings Volume 6438, 64380A (2007) https://doi.org/10.1117/12.705732

KEYWORDS: Luminescence, Biopsy, Fluorescence spectroscopy, Tissues, Skin, Photodynamic therapy, Microscopes, Biological research, Image analysis, Image filtering

Read Abstract +

Proceedings Article | 6 March 2006 Paper

Measurement of fluorophore concentration in scattering media by one single optical fiber

Herbert Stepp, Tobias Beck, Wolfgang Beyer, Christian Pfaller, Ronald Sroka, Reinhold Baumgartner

Proceedings Volume 6139, 61390S (2006) https://doi.org/10.1117/12.646144

KEYWORDS: Optical fibers, Tissue optics, Absorption, Photodynamic therapy, Liquids, Luminescence, Scattering, Monte Carlo methods, Scattering media, Light scattering

Read Abstract +

Proceedings Article | 22 February 2006 Paper

Fluorescence guided resection for malignant glioma using 5-aminolevulinic acid

Herbert Stepp, Tobias Beck, Thomas Pongratz, Thomas Meinel, Jörg Tonn, Walter Stummer

Proceedings Volume 6078, 60782W (2006) https://doi.org/10.1117/12.652069

KEYWORDS: Photodynamic therapy, Tumors, Luminescence, Tissues, Surgery, Magnetic resonance imaging, Fluorescence spectroscopy, Tissue optics, Microscopes, Blood

Read Abstract +

Proceedings Article | 25 April 2005 Paper

Integral photodynamic therapy of bladder cancer using 5-ALA and white light

Reinhold Baumgartner, Raphaela Waidelich, Wolfgang Beyer, Herbert Stepp, Ruth Knuechel-Clarke, Alfons Hofstetter

Proceedings Volume 5686, (2005) https://doi.org/10.1117/12.609197

KEYWORDS: Bladder, Photodynamic therapy, Bladder cancer, Tumors, Tissue optics, Light sources, Absorption, Lamps, Xenon, Light scattering

Read Abstract +

Proceedings Article | 25 April 2005 Paper

Fluorescence-guided resections and photodynamic therapy for malignant gliomas using 5-aminolevulinic acid

Herbert Stepp, Tobias Beck, Wolfgang Beyer, Thomas Pongratz, Ronald Sroka, Reinhold Baumgartner, Walter Stummer, Bernhard Olzowy, Jan Mehrkens, Joerg Tonn, Hans Reulen

Proceedings Volume 5686, (2005) https://doi.org/10.1117/12.591526

KEYWORDS: Tumors, Luminescence, Photodynamic therapy, Tissues, Magnetic resonance imaging, Brain, Tissue optics, Optical fibers, Surgery, Fluorescence spectroscopy

Read Abstract +

SPIE Journal Paper | 1 April 2002 Open Access

Localization and staging of cervical intraepithelial neoplasia using double ratio fluorescence imaging

Arjen Bogaards, Maurice Aalders, C. Zeyl, Sjoerd de Blok, C. Dannecker, Peter Hillemanns, Herbert Stepp, Hericus Sterenborg

JBO, Vol. 7, Issue 02, (April 2002) https://doi.org/10.1117/12.10.1117/1.1463045

KEYWORDS: Luminescence, Biopsy, Cervix, Tissues, Monte Carlo methods, Tumors, Prototyping, Cervical cancer, Fluorescence spectroscopy, Imaging devices

DOWNLOAD PAPER

Proceedings Article | 31 October 2001 Paper

Clinical results with UV-excited autofluorescence spectroscopy in different organs

Herbert Stepp, Alexander Hohla

Proceedings Volume 4432, (2001) https://doi.org/10.1117/12.447139

KEYWORDS: Luminescence, Tissues, Tumors, Brain, Bladder, Ultraviolet radiation, Spectroscopy, Bladder cancer, Biopsy, Lung

Read Abstract +

Proceedings Article | 31 January 2001 Paper

Differential accumulation and organ-specific metabolism of 5-aminolevulinic acid between cancer cells and normal epithelial and stromal cells

Rene Krieg, Joachim Rauch, Juergen Seidl, Herbert Stepp, Helmut Messmann, Ruth Knuechel

Proceedings Volume 4156, (2001) https://doi.org/10.1117/12.413718

KEYWORDS: Iron, Luminescence, Mode conditioning cables, Proteins, Nickel, Flow cytometry, Cancer, Photodynamic therapy, Receptors, Tumors

Read Abstract +

Proceedings Article | 31 January 2001 Paper

Formation of 5-aminolevulinic-acid (ALA) induced protoporphyrin IX (PPIX) and photodynamic effectiveness in human urothelial cell lines

Juergen Seidl, Rene Krieg, Joachim Rauch, Raphaela Waidelich, Herbert Stepp, Ruth Knuechel

Proceedings Volume 4156, (2001) https://doi.org/10.1117/12.413722

KEYWORDS: Photodynamic therapy, Tumors, Luminescence, Fluorescence correlation spectroscopy, In vitro testing, Bladder cancer, Flow cytometry, Xenon, Projection systems, Bladder

Read Abstract +

Proceedings Article | 28 June 2000 Paper

Basic principles of fluorescence detection with use of 5-ALA

Reinhold Baumgartner, Herbert Stepp

Proceedings Volume 4166, (2000) https://doi.org/10.1117/12.389470

KEYWORDS: Luminescence, Tumors, Fluorescence spectroscopy, Optical filters, Endoscopy, Tissues, Tissue optics, Endoscopes, Lamps, Laser development

Read Abstract +

Proceedings Article | 28 June 2000 Paper

Clinical experience with the use of 5-ALA for the detection of superficial bladder cancer

Herbert Stepp, Reinhold Baumgartner, Ruth Knuechel, M. Kriegmair, H. Stepp, D. Zaak, Alfons Hofstetter

Proceedings Volume 4166, (2000) https://doi.org/10.1117/12.389471

KEYWORDS: Luminescence, Tumors, Endoscopy, Bladder cancer, Bladder, Cystoscopy, Cell biology, Tissues, Biopsy, Tantalum

Read Abstract +

Proceedings Article | 28 June 2000 Paper

Clinical experiences with fluorescence guided resection of malignant glioma

Walter Stummer, Susanne Stocker, Herbert Stepp, Karl Bise, Hanns-Juergen Reulen, Reinhold Baumgartner

Proceedings Volume 4166, (2000) https://doi.org/10.1117/12.389472

KEYWORDS: Tumors, Luminescence, Surgery, Tissues, Microscopes, Laser therapeutics, Visualization, Tissue optics, Waveguides, Magnetic resonance imaging

Read Abstract +

Proceedings Article | 3 February 1999 Paper

5-aminolevulinic acid (ALA) mediated photodynamic therapy of bladder cancer cell lines

Sonja Fickweiler, Rene Krieg, Herbert Stepp, Ferdinand Hofstaedter, Ruth Knuechel

Proceedings Volume 3563, (1999) https://doi.org/10.1117/12.339130

KEYWORDS: Photodynamic therapy, Luminescence, Bladder cancer, Proteins, Cancer, Nickel, Flow cytometry, Magnesium, Bladder, Calibration

Read Abstract +

Proceedings Article | 29 December 1997 Paper

New developments in fluorescence detection of ALA-induced protoporphyrin IX for cancer localization

Herbert Stepp, Reinhold Baumgartner, Christian Betz, Karl Bise, P. Brand, Fernando Gamarra, Karl Haeussinger, Peter Hillemanns, Rudolf Huber, Ruth Knuechel, M. Kriegmair, Andreas Leunig, J. Pichler, Kai Rick, H. Schulz, F. Stanzel, Susanne Stocker, Simon Wagner, H. Weigandt

Proceedings Volume 3197, (1997) https://doi.org/10.1117/12.297952

KEYWORDS: Luminescence, Tissues, Fluorescence spectroscopy, Tissue optics, Tumors, Cystoscopy, Optical filters, Bladder cancer, Biopsy, Light sources

Read Abstract +

Proceedings Article | 11 December 1996 Paper

Noninvasive NADH measurements for clinical applications

Werner Schramm, Wolfgang Hoehne, Herbert Stepp, Andreas Leunig

Proceedings Volume 2927, (1996) https://doi.org/10.1117/12.260634

KEYWORDS: Tissues, Diagnostics, Luminescence, Transplantation, Surgery, Tumors, Sensors, Spectroscopy, Fluorescence spectroscopy, Clinical research

Read Abstract +

Proceedings Article | 3 December 1996 Paper

Fluorescence photodetection of head and neck cancer following topical or systemic application of 5-aminolevulinic acid

Andreas Leunig, Kai Rick, Herbert Stepp, Ralph Gutmann, Alwin Goetz, Reinhold Baumgartner, Jens Feyh

Proceedings Volume 2922, (1996) https://doi.org/10.1117/12.260713

KEYWORDS: Luminescence, Tumors, Tissues, Cancer, Tissue optics, Head, Neck, Diagnostics, Photodetectors, CCD cameras

Read Abstract +

Proceedings Article | 27 December 1995 Paper

Fluorescence imaging and spectroscopy of ALA-induced protoporphyrin IX preferentially accumulated in tumor tissue

Herbert Stepp, Reinhold Baumgartner, Wolfgang Beyer, Ruth Knuechel, T. Koerner, M. Kriegmair, Kai Rick, Pia Steinbach, Alfons Hofstetter

Proceedings Volume 2627, (1995) https://doi.org/10.1117/12.228884

KEYWORDS: Luminescence, Tissue optics, Absorption, Tissues, Image processing, Plasma, Blood, Imaging spectroscopy, Tumors, Skin

Read Abstract +

Proceedings Article | 1 March 1995 Paper

5-aminolaevulinic acid for fluorescence diagnosis and photodynamic therapy of bronchial cancer: a case report

Fernando Gamarra, Reinhold Baumgartner, Herbert Stepp, Kai Rick, A. Leberig, Rudolf Huber

Proceedings Volume 2371, (1995) https://doi.org/10.1117/12.203383

KEYWORDS: Photodynamic therapy, Luminescence, Tumors, Cancer, Aerosols, Lung cancer, Visual analytics, Visualization, Optical spectroscopy, Spectroscopy

Read Abstract +

Proceedings Article | 4 January 1995 Paper

Time-gated spectroscopy of intrinsic fluorophores in cells and tissues

Herbert Schneckenburger, Michael Gschwend, Ruediger Paul, Herbert Stepp, Kai Rick, Volkmar Betz, Wolfgang Strauss

Proceedings Volume 2324, (1995) https://doi.org/10.1117/12.198719

KEYWORDS: Luminescence, Tissues, Collagen, Oxygen, Spectroscopy, Molecules, Bladder, Biopsy, Imaging spectroscopy, Proteins

Read Abstract +

Proceedings Article | 4 January 1995 Paper

Bladder tissue diagnostics utilizing Protoporphyrin IX fluorescence detection

Herbert Stepp, Reinhold Baumgartner, Wolfgang Beyer, Ruth Knuechel, Kai Rick, Pia Steinbach, M. Kriegmair

Proceedings Volume 2324, (1995) https://doi.org/10.1117/12.198739

KEYWORDS: Luminescence, Tumors, Tissues, Tissue optics, Cystoscopy, Bladder, Absorption, Scattering, Blood, Monte Carlo methods

Read Abstract +

Proceedings Article | 15 January 1994 Paper

Delta-ALA-assisted fluorescence detection of cancer in the urinary bladder

Reinhold Baumgartner, M. Kriegmair, Ruth Knuechel, Herbert Stepp, Peter Heil, Alfons Hofstetter

Proceedings Volume 2081, (1994) https://doi.org/10.1117/12.166812

KEYWORDS: Luminescence, Tumors, Biopsy, Cystoscopy, Bladder, Bladder cancer, Tissue optics, Fluorescence spectroscopy, Visualization, Tissues

Read Abstract +

Proceedings Article | 18 June 1993 Paper

Photodynamic diagnosis following intravesical instillation of aminolevulinic acid (ALA): first clinical experiences in urology

Reinhold Baumgartner, M. Kriegmair, Herbert Stepp, W. Lumper, Peter Heil, Rainer Riesenberg, Susanne Stocker, Alfons Hofstetter

Proceedings Volume 1881, (1993) https://doi.org/10.1117/12.146310

KEYWORDS: Tumors, Luminescence, Bladder, Tissue optics, Visualization, Tumor growth modeling, Endoscopy, Tissues, Biopsy, Fluorescence spectroscopy

Read Abstract +

Proceedings Article | 1 August 1992 Paper

Fiber optic probes for tissue illumination in photodynamic diagnosis and therapy

Reinhold Baumgartner, Wolfgang Beyer, G. Friedsam, Dieter Jocham, Axel Noack, Ronald Sroka, Herbert Stepp, Eberhard Unsoeld

Proceedings Volume 1649, (1992) https://doi.org/10.1117/12.60226

KEYWORDS: Endoscopes, Photodynamic therapy, Fiber optics, Tissue optics, Microlens, Luminescence, Optical fibers, Lenses, Lung, Tumors

Read Abstract +

Proceedings Article | 1 November 1991 Paper

Improved instrumentation for photodynamic fluorescence detection of cancer

Reinhold Baumgartner, Peter Heil, Dieter Jocham, M. Kriegmair, Herbert Stepp, Eberhard Unsoeld

Proceedings Volume 1525, (1991) https://doi.org/10.1117/12.48231

KEYWORDS: Luminescence, Fluorescence spectroscopy, Cancer, Tumors, Tissue optics, Video, Diagnostics, Endoscopes, Imaging systems, Laser tissue interaction

Read Abstract +

Proceedings Article | 1 July 1990 Paper

Uniform light distribution in hollow organs by means of backscattering layers

Wolfgang Beyer, Reinhold Baumgartner, Christian Ell, Armin Heinze, Dieter Jocham, Ronald Sroka, Herbert Stepp, Eberhard Unsoeld

Proceedings Volume 1201, (1990) https://doi.org/10.1117/12.17549

KEYWORDS: Backscatter, Homogenization, Spherical lenses, Tissue optics, Scattering, Tumors, Tissues, Bladder, Optical fibers, Medicine

Read Abstract +

Proceedings Article | 1 July 1990 Paper

Modified fiber tips for light application in hollow organs

Armin Heinze, Wolfgang Beyer, M. Krug, K. Schaarschmidt, Ronald Sroka, Herbert Stepp, Eberhard Unsoeld, G. Willital

Proceedings Volume 1201, (1990) https://doi.org/10.1117/12.17550

KEYWORDS: Light scattering, Scattering, Photodynamic therapy, Optical fibers, Medicine, Esophagus, Mirrors, Refraction, Bladder, Tissues

Read Abstract +

Showing 5 of 57 publications

Conference Committee Involvement (25)

Clinical and Translational Neurophotonics 2025

25 January 2025 | San Francisco, California, United States

Clinical and Translational Neurophotonics 2023

28 January 2023 | San Francisco, California, United States

Clinical and Translational Neurophotonics 2022

22 January 2022 | San Francisco, California, United States

Clinical and Translational Neurophotonics 2021

6 March 2021 | Online Only, California, United States

Clinical and Translational Neurophotonics 2020

1 February 2020 | San Francisco, California, United States

17th International Photodynamic Association World Congress

28 June 2019 | Cambridge, Massachusetts, United States

Translation of Lasers and Biophotonics Technologies and Procedures: Toward the Clinic

23 June 2019 | Munich, Germany

Clinical and Translational Neurophotonics 2019

2 February 2019 | San Francisco, California, United States

Clinical and Translational Neurophotonics 2018

27 January 2018 | San Francisco, California, United States

Medical Laser Applications and Laser-Tissue Interactions VIII

25 June 2017 | Munich, Germany

Clinical and Translational Neurophotonics

28 January 2017 | San Francisco, California, United States

Clinical and Translational Neurophotonics

13 February 2016 | San Francisco, California, United States

Medical Laser Applications and Laser-Tissue Interactions VII

21 June 2015 | Munich, Germany