Publikationen

2022

  • Lange, B;Ozimek, T;Wießmeyer, J R;Kramer, M W.;Merseburger, A S. and Brinkmann, R: Theoretical and experimental evaluation of the distance dependence of fiber-based fluorescence and reflection measurements for laser lithotripsy. Biomedical Physics & Engineering Express, no. 8, pp. 055023, 2022
    BibTeX Link
    @article{Lange2022,
       author = {Lange, B;Ozimek, T;Wießmeyer, J R;Kramer, M W.;Merseburger, A S. and Brinkmann, R},
       title = {Theoretical and experimental evaluation of the distance dependence of fiber-based fluorescence and reflection measurements for laser lithotripsy},
       journal = {Biomedical Physics & Engineering Express},
       volume = {8},
       number = {5},
    abstract = {Objectives. In laser lithotripsy, a green aiming beam overlying the infrared (IR) treatment radiation gives rise to reflection and fluorescence signals that can be measured via the treatment fiber. While stone autofluorescence is used for target detection, the condition of the fiber can be assessed based on its Fresnel reflection. For good applicability, fluorescence detection of stones should work even when the stone and fiber are not in direct contact. Fiber breakage detection, on the other hand, can be falsified if surfaces located in front of the fiber reflect light from the aiming laser back into it. For both applications, therefore, a fundamental investigation of the dependence of the signal amplitude on the distance between fiber and surface is important. Methods. Calculations of the signal drop of fluorescence or diffuse and specular reflection with increasing fiber distance were performed using ray tracing based on a simple geometric model for different fiber core diameters. Reflection signals from a mirror, diffuse reflector, human calculi, and porcine renal tissue placed in water were measured at varying distances (0–5 mm). For human calculi, fluorescence signals were recorded simultaneously. Results. The calculations showed a linear signal decrease down to ∼60% of the maximum signal (fiber in contact). The distance z at which the signal drops to for example 50% depends linearly on the diameter of the fiber core. For fibers used in lithotripsy and positioned in water, z50% ranges from 0.55 mm (200 μm core diameter) to 2.73 mm, (1 mm core diameter). The calculations were in good agreement with the experimental results. Conclusions. The autofluorescence signals of stones can be measured in non-contact mode. Evaluating the Fresnel signal of the end face of the fiber to detect breakage is possible unless the fiber is situated less than some millimeters to reflecting surfaces.},
    keywords = {urolithiasis, laser lithotripsy, fluorescence, reflectance},
       pages = {055023},
       ISSN = {2057-1976},
       DOI = {10.1088/2057-1976/ac82c7},
       
       year = {2022},
       type = {Journal Article}
    }
    
  • Strenge, P;Lange, B;Grill, C;Draxinger, W;Danicke, V;Theisen-Kunde, D;Hagel, C;Spahr-Hess, S;Bonsanto, Matteo M.;Huber, R;Handels, H and Brinkmann, R: Registration of histological brain images onto optical coherence tomography images based on shape information. Physics in Medicine & Biology, 2022
    BibTeX Link
    @article{Strenge2022,
       author = {Strenge, P;Lange, B;Grill, C;Draxinger, W;Danicke, V;Theisen-Kunde, D;Hagel, C;Spahr-Hess, S;Bonsanto, Matteo M.;Huber, R;Handels, H and Brinkmann, R},
       title = {Registration of histological brain images onto optical coherence tomography images based on shape information},
    keywords = {brain, glioblastoma multiforme, shape, OCT, optical coherence tomography, AG-Huber_OCT,},
       journal = {Physics in Medicine & Biology},
       ISSN = {0031-9155},
       url = {http://iopscience.iop.org/article/10.1088/1361-6560/ac6d9d},
       year = {2022},
       type = {Journal Article}
    }
    
  • Strenge, P.;Lange, B.;Grill,C.;Danicke,V.;Theisen-Kunde, D.;Hagel, C.;Spahr-Hess, S.;;Bonsanto, Matteo M.;Handels, H.; and Huber, R.;Brinkmann, R.: Differentiation of different stages of brain tumor infiltration using optical coherence tomography: Comparison of two systems and histology. Frontiers in Oncology, 2022
    BibTeX Link Link
    @article{Strenge 2022,
       author = {Strenge, P.;Lange, B.;Grill,C.;Danicke,V.;Theisen-Kunde, D.;Hagel, C.;Spahr-Hess, S.;;Bonsanto, Matteo M.;Handels, H.; and Huber, R.;Brinkmann, R.},
       title = {Differentiation of different stages of brain tumor infiltration using optical coherence tomography: Comparison of two systems and histology},
       journal = {Frontiers in Oncology},
    Keywords = {AG-Huber_FDML, AG-Huber_OCT, brain, tumor, glioblastoma multiforme, OCT, neural network, attenuation (absorption)
    coefficient, optical coherence tomography},
       DOI = {https://doi.org/10.3389/fonc.2022.896060},
       url = {https://www.frontiersin.org/articles/10.3389/fonc.2022.896060/full},
       year = {2022},
       type = {Journal Article}
    }
    

2021

  • Jäckle, S;Lange, A;García-Vázquez, V;Eixmann, T;Matysiak, F;Sieren, M M;Horn, M;Schulz-Hildebrandt, H;Hüttmann, G;Ernst, F;Heldmann, St;Pätz, T and Preusser, T: Instrument localisation for endovascular aneurysm repair: Comparison of two methods based on tracking systems or using imaging. The International Journal of Medical Robotics and Computer Assisted Surgery, no. 17(6), pp. e2327, 2021
    BibTeX Link
    @article{Jäckle 2021-2,
       author = {Jäckle, S;Lange, A;García-Vázquez, V;Eixmann, T;Matysiak, F;Sieren, M M;Horn, M;Schulz-Hildebrandt, H;Hüttmann, G;Ernst, F;Heldmann, St;Pätz, T and Preusser, T},
       title = {Instrument localisation for endovascular aneurysm repair: Comparison of two methods based on tracking systems or using imaging},
       journal = {The International Journal of Medical Robotics and Computer Assisted Surgery},
       volume = {17(6)},
      
       pages = {e2327},
       ISSN = {1478-5951},
       DOI = {https://doi.org/10.1002/rcs.2327},
     
       year = {2021},
       type = {Journal Article}
    }
    
  • Krumm, L S;Lange, B;Ozimek, T;Wießmeyer, J R;Kramer, M W;Merseburger, A S and Brinkman, R: Fiber-based Fluorescence and Reflection Measurements during Laser Lithotripsy. in ECBO, 2021
    BibTeX Link
    @inproceedings{Krumm 2021,
       author = {Krumm, L S;Lange, B;Ozimek, T;Wießmeyer, J R;Kramer, M W;Merseburger, A S and Brinkman, R},
       title = {Fiber-based Fluorescence and Reflection Measurements during Laser Lithotripsy},
    Year = {2021},
       booktitle = {ECBO},
    DOI = {https://doi.org/10.1117/12.2614447},
       type = {Conference Proceedings}
    }
    
  • P. Strenge, B. Lange, C. Grill, W. Draxinger, V. Danicke, D. Theisen-Kunde, H. Handels, C. Hagel, M. Bonsanto, R. Huber and R. Brinkmann: Creating a depth-resolved OCT-dataset for supervised classification based on ex vivo human brain samples. in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXV, no. 11630, pp. 66 - 73, SPIE, 2021
    BibTeX Link
    @inproceedings{Strenge2021,
    author = {P. Strenge, B. Lange, C. Grill, W. Draxinger, V. Danicke, D. Theisen-Kunde, H. Handels, C. Hagel, M. Bonsanto, R. Huber and R. Brinkmann},
    title = {{Creating a depth-resolved OCT-dataset for supervised classification based on ex vivo human brain samples}},
    volume = {11630},
    booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXV},
    editor = {Joseph A. Izatt and James G. Fujimoto},
    organization = {International Society for Optics and Photonics},
    publisher = {SPIE},
    pages = {66 -- 73},
    abstract = {Optical coherence tomography (OCT) has the potential to become an additional imaging modality for surgical guidance in the field of neurosurgery, especially when it comes to the detection of different infiltration grades of glioblastoma multiforme at the tumor border. Interpretation of the images, however, is still a big challenge. A method to create a labeled OCT dataset based on ex vivo brain samples is introduced. The tissue samples were embedded in an agarose mold giving them a distinctive shape before images were acquired with two OCT systems (spectral domain (SD) and swept source (SS) OCT) and histological sections were created and segmented by a neuropathologist. Based on the given shape, the corresponding OCT images for each histological image can be determined. The transfer of the labels from the histological images onto the OCT images was done with a non-affine image registration approach based on the tissue shape. It was demonstrated that finding OCT images of a tissue sample corresponding to segmented histological images without any color or laser marking is possible. It was also shown that the set labels can be transferred onto OCT images. The accuracy of method is 26 ± 11 pixel, which translates to 192 ± 75 μm for the SS-OCT and 94 ± 43 μm for the SD-OCT. The dataset consists of several hundred labeled OCT images, which can be used to train a classification algorithm.},
    keywords = {AG-Huber_OCT, optical coherence tomography, OCT, image registration, glioblastoma multiforme, MHz-OCT, brain imaging, tumor, neurosurgery},
    year = {2021},
    URL = {hhttps://doi.org/10.1117/12.2578391}
    }
  • P. Strenge, B. Lange, C. Grill, W. Draxinger, V. Danicke, D. Theisen-Kunde, H. Handels, M. M. Bonsanto, C. Hagel, R. Huber and R. Brinkmann: Comparison of two optical coherence tomography systems to identify human brain tumor. European Conferences on Biomedical Optics 2021 (ECBO), pp. EW1C.7, Optical Society of America, 2021
    BibTeX Link
    @inproceedings{Strenge:21,
    author = {P. Strenge, B. Lange, C. Grill, W. Draxinger, V. Danicke, D. Theisen-Kunde, H. Handels, M. M. Bonsanto, C. Hagel, R. Huber and R. Brinkmann},
    journal = {European Conferences on Biomedical Optics 2021 (ECBO)},
    keywords = {AG-Huber_OCT; Absorption coefficient; Attenuation coefficient; Fourier domain mode locking; Multiple scattering; Optical coherence tomography; Spectral domain optical coherence tomography},
    pages = {EW1C.7},
    publisher = {Optical Society of America},
    title = {Comparison of two optical coherence tomography systems to identify human brain tumor},
    year = {2021},
    url = {https://doi.org/10.1117/12.2616044},
    abstract = {The identification of ex vivo brain tumor tissue was investigated with two different optical coherence tomography systems exploiting two optical parameters. The optical parameters were calculated from semantically labelled OCT B-scans.},
    }
  • P. Strenge, B. Lange, C. Grill, W. Draxinger, V. Danicke, D. Theisen-Kunde, H. Handels, M. Bonsanto, C. Hagel, R. Huber and R. Brinkmann: Characterization of brain tumor tissue with 1310 nm optical coherence tomography. in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXV, no. 11630, pp. 74 - 80, SPIE, 2021
    BibTeX Link
    @inproceedings{Strenge2021A,
    author = {P. Strenge, B. Lange, C. Grill, W. Draxinger, V. Danicke, D. Theisen-Kunde, H. Handels, M. Bonsanto, C. Hagel, R. Huber and R. Brinkmann},
    title = {{Characterization of brain tumor tissue with 1310 nm optical coherence tomography}},
    volume = {11630},
    booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXV},
    editor = {Joseph A. Izatt and James G. Fujimoto},
    organization = {International Society for Optics and Photonics},
    publisher = {SPIE},
    pages = {74 -- 80},
    abstract = {The separation of tumorous brain tissue and healthy brain tissue is still a big challenge in the field of neurosurgery, especially when it comes to the detection of different infiltration grades of glioblastoma multiforme at the tumor border. On the basis of a recently created labelled OCT dataset of ex vivo glioblastoma multiforme tumor samples the detection of brain tumor tissue and the identification of zones with varying degrees of infiltration of tumor cells was investigated. The identification was based on the optical properties, which were extracted by an exponential fit function. The results showed that a separation of tumorous tissue and healthy white matter based on these optical properties is possible. A support vector machine was trained on the optical properties to separate tumor from healthy white matter tissue, which achieved a sensitivity of 91% and a specificity of 76% on an independent training dataset.},
    keywords = {AG-Huber_OCT, optical coherence tomography, OCT, glioblastoma multiforme, MHz-OCT, brain imaging, tumor, neurosurgery},
    year = {2021},
    URL = {hhttps://doi.org/10.1117/12.2578409}
    }

2020

  • P. Strenge and B. Lange and C. Grill and W. Draxinger and M. M. Bonsanto and C. Hagel and R. Huber and R. Brinkmann: Segmented OCT data set for depth resolved brain tumor detection validated by histological analysis. in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIV, no. 11228, pp. 82 - 89, SPIE, 2020
    BibTeX Link Datei
    @inproceedings{Strenge2020,
    author = {P. Strenge and B. Lange and C. Grill and W. Draxinger and M. M. Bonsanto and C. Hagel and R. Huber and R. Brinkmann},
    title = {{Segmented OCT data set for depth resolved brain tumor detection validated by histological analysis}},
    volume = {11228},
    booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIV},
    editor = {Joseph A. Izatt and James G. Fujimoto},
    organization = {International Society for Optics and Photonics},
    publisher = {SPIE},
    pages = {82 -- 89},
    keywords = {AG-Huber_OCT, Optical coherence tomography, OCT, FDML Laser, MHz-OCT, brain tumor, brain imaging, neurosurgery},
    year = {2020},
    
    URL = {  https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11228/112282O/Segmented-OCT-data-set-for-depth-resolved-brain-tumor-detection/10.1117/12.2545659.short}
    }
    

2019

  • Strittmatter, Frank;Eisel, Maximilian;Brinkmann, Ralf;Cordes, Jens;Lange, Birgit and Sroka, Ronald: Laser-induced lithotripsy: a review, insight into laboratory work, and lessons learned. Translational Biophotonics, no. n/a, pp. e201900029, 2019
    BibTeX Link Link
    @article{Brinkmann2020,
       author = {Strittmatter, F;Eisel, M; Brinkmann, R; Cordes, J;Lange, B and Sroka, R},
       title = {Laser-induced lithotripsy: a review, insight into laboratory work, and lessons learned},
       journal = {Translational Biophotonics},
       volume = {n/a},
       number = {n/a},
       pages = {e201900029},
       ISSN = {2627-1850},
       DOI = {10.1002/tbio.201900029},
       url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/tbio.201900029},
       year = {2019},
       type = {Journal Article}
    }
    
  • Lange, B;Cordes, J. and Brinkmann, R: Exploiting the aiming beam to increase the safety of laser lithotripsy: Experimental evaluation of light reflection and fluorescence. Lasers in Surgery and Medicine, 2019
    BibTeX Link
    @article{Lange 2019,
       author = {Lange, B;Cordes, J. and Brinkmann, R},
       title = {Exploiting the aiming beam to increase the safety of laser lithotripsy: Experimental evaluation of light reflection and fluorescence},
       journal = {Lasers in Surgery and Medicine},
       ISSN = {0196-8092},   
       url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/lsm.23154},
       year = {2019},
       type = {Journal Article}
    }
    
  • Lange, B;Cordes, J. and Brinkmann, R: Exploiting the aiming beam to increase the safety of laser lithotripsy: Experimental evaluation of light reflection and fluorescence. Lasers in Surgery and Medicine, 2019
    BibTeX Link
    @article{Lange2019,
       author = {Lange, B;Cordes, J. and Brinkmann, R},
       title = {Exploiting the aiming beam to increase the safety of laser lithotripsy: Experimental evaluation of light reflection and fluorescence},
       journal = {Lasers in Surgery and Medicine},
       
       ISSN = {0196-8092},
       DOI = {10.1002/lsm.23154},
       
       year = {2019},
       type = {Journal Article}
    }
    
  • Strenge,P; Lange,B; Grill, C; Draxinger, W; Danicke, V; Theisen-Kunde, D; Bonsanto, M; Huber, R and Brinkmann R: Ex vivo and in vivo imaging of human brain tissue with different OCT systems. in Proc. SPIE 11078, Optical Coherence Imaging Techniques and Imaging in Scattering Media III, 110781C, no. 11078, 2019
    BibTeX Link Datei
    @proceeding{Strenge2019,
    author = {Strenge,P; Lange,B; Grill, C; Draxinger, W; Danicke, V; Theisen-Kunde, D; Bonsanto, M; Huber, R and Brinkmann R},
    title = {Ex vivo and in vivo imaging of human brain tissue with different OCT systems},
    volume = {11078},
    year = {2019},
    
    URL = {  https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11078/2526932/Ex-vivo-and-in-vivo-imaging-of-human-brain-tissue/10.1117/12.2526932.short},
    keywords = {AG-Huber_OCT},
    booktitle =    {Proc. SPIE 11078, Optical Coherence Imaging Techniques and Imaging in Scattering Media III, 110781C},
    eprint = {}
    }
    

2017

  • Lange, Birgit and Jocham, Dieter and Brinkmann, Ralf and Cordes, Jens: Stone/tissue differentiation for Holmium laser lithotripsy using autofluorescence: Clinical proof of concept study. Lasers in Surgery and Medicine, no. 49, pp. 361-365, 2017
    BibTeX Link
    @article{Lange2017,
       author = {Lange, Birgit and Jocham, Dieter and Brinkmann, Ralf and Cordes, Jens},
       title = {Stone/tissue differentiation for Holmium laser lithotripsy using autofluorescence: Clinical proof of concept study},
       journal = {Lasers in Surgery and Medicine},
       volume = {49},
       number = {4},
       pages = {361-365},
       ISSN = {1096-9101},
       DOI = {10.1002/lsm.22611},
       year = {2017},
       type = {Journal Article}
    }
    

2015

  • Lange, B. and Cordes, J. and Brinkmann, R.: Stone/tissue differentiation for holmium laser lithotripsy using autofluorescence. Lasers Surg Med, no. 47, pp. 737-44, 2015
    BibTeX Link
    @article{Lange2015,
       author = {Lange, B. and Cordes, J. and Brinkmann, R.},
       title = {Stone/tissue differentiation for holmium laser lithotripsy using autofluorescence},
       journal = {Lasers Surg Med},
       volume = {47},
       number = {9},
       pages = {737-44},
       note = {1096-9101
    Lange, Birgit
    Cordes, Jens
    Brinkmann, Ralf
    Journal Article
    United States
    Lasers Surg Med. 2015 Nov;47(9):737-44. doi: 10.1002/lsm.22418. Epub 2015 Sep 22.},
       abstract = {BACKGROUND AND OBJECTIVES: Holmium laser lithotripsy is a safe and effective method to disintegrate urinary stones of all compositions in an endoscopic procedure. However, handling and safety could be improved by a real-time feedback system permanently monitoring the position of the treatment fiber. The laser is fired only when the fiber is identified as being placed in front of stone. This work evaluates the potential of fluorescence detection with an excitation wavelength of 532 nm for this purpose. MATERIALS AND METHODS: A fiber-based fluorescence measurement was set-up to acquire autofluorescence signals from several human renal calculi, artificial stones, and porcine tissue samples (renal calix and ureter). Three different approaches were investigated. First, experiments were performed with a pulsed laser source with a wavelength of 532 nm, pulse energy 36.5 +/- 1 muJ, pulse duration 1.2 +/- 0.5 nanoseconds, and a repetition rate of 1 kHz with 15 urinary concretions. In the second step, a series of measurements on 42 human urinary calculi samples was carried out using low power continuous wave excitation of 0.4 +/- 0.1 mW. Fluorescence was also measured simultaneously to stone fragmentation by holmium laser pulses (pulse energy 240 +/- 50 mJ, repetition rate 10 Hz). Finally, a modulated excitation/detection scheme (lock-in technique) was implemented to render fluorescence detection insensitive to white background light. RESULTS: Unlike porcine renal calix, ureter, and artificial stone human urinary calculi show a strong fluorescence signal when excited with 532 nm. With pulsed excitation on urinary stone (20,000 +/- 11,000) counts were registered at 587 nm with the CCD-array of a grating spectrometer in an integration time of 50 milliseconds. Tissue gave lower count rates of </=(5,500 +/- 1,100) even with longer integration times (500 milliseconds/1 second). With a cw excitation power of 0.4 mW (13,000 +/- 11,000) counts were registered in an integration time of 200 milliseconds at 587 nm (porcine renal calix: (770 +/- 340)). Modulated excitation (66 Hz) with an average power of 0.3 mW and detection with a photodiode resulted in a lock-in amplifier signal of 1.5-4.3V on stone (background and skin: <0.5V). CONCLUSION: With the lock-in technique, autofluorescence from stones can be detected with only the average excitation power of a green aiming beam overlaid to the Ho:YAG-laser beam (power </= 1 mW). Since tissue shows very little autofluorescence when excited with 532 nm, this fluorescence signal enables monitoring of the correct position of the treatment fiber during ureteroscopic procedures. Lasers Surg. Med. 47:737-744, 2015. (c) 2015 Wiley Periodicals, Inc.},
       keywords = {Holmium laser
    feedback control
    fluorescence
    laser lithotripsy},
       ISSN = {0196-8092},
       DOI = {10.1002/lsm.22418},
       year = {2015},
       type = {Journal Article}
    }
    
  • Huttmann, Gereon and Koinzer, Stefan Otto Johannes and Müller, Heike and Ellerkamp, Iris and Baade, Alex and Moltmann, Moritz and Theisen-Kunde, Dirk and Lange, Birgit and Brinkmann, Ralf and Birngruber, Reginald: Predicting ophthalmoscopic visibility of retinal photocoagulation lesions byhigh-speedOCT: an animal studyinrabbits. Investigative Ophthalmology & Visual Science, no. 56, pp. 5980-5980, 2015
    BibTeX
    @article{Hüttmann2015,
       author = {Huttmann, Gereon and Koinzer, Stefan Otto Johannes and Müller, Heike and Ellerkamp, Iris and Baade, Alex and Moltmann, Moritz and Theisen-Kunde, Dirk and Lange, Birgit and Brinkmann, Ralf and Birngruber, Reginald},
       title = {Predicting ophthalmoscopic visibility of retinal photocoagulation lesions byhigh-speedOCT: an animal studyinrabbits},
       journal = {Investigative Ophthalmology & Visual Science},
       volume = {56},
       number = {7},
       pages = {5980-5980},
       ISSN = {1552-5783},
       year = {2015},
       type = {Journal Article}
    }
    

2013

  • Cordes, Jens and Nguyen, Felix and Lange, Birgit and Brinkmann, Ralf and Jocham, Dieter: Damage of Stone Baskets by Endourologic Lithotripters: A Laboratory Study of 5 Lithotripters and 4 Basket Types. Advances in Urology, no. 2013, pp. 6, 2013
    BibTeX Link
    @article{Cordes2013,
       author = {Cordes, Jens and Nguyen, Felix and Lange, Birgit and Brinkmann, Ralf and Jocham, Dieter},
       title = {Damage of Stone Baskets by Endourologic Lithotripters: A Laboratory Study of 5 Lithotripters and 4 Basket Types},
       journal = {Advances in Urology},
       volume = {2013},
       pages = {6},
       DOI = {10.1155/2013/632790},
       url = {http://dx.doi.org/10.1155/2013/632790},
       year = {2013},
       type = {Journal Article}
    }
    

2009

  • Schlott, Kerstin and Langejürgen, Jens and Bever, Marco and Koinzer, Stefan and Birngruber, Reginald and Brinkmann, Ralf: Time resolved detection of tissue denaturation during retinal photocoagulation. pp. 73730E-73730E, 2009
    BibTeX Link
    @inproceedings{Schlott2009,
       author = {Schlott, Kerstin and Langejürgen, Jens and Bever, Marco and Koinzer, Stefan and Birngruber, Reginald and Brinkmann, Ralf},
       title = {Time resolved detection of tissue denaturation during retinal photocoagulation},
       editor = {7373, Proc. SPIE},
       pages = {73730E-73730E},
       note = {10.1117/12.831877},
       abstract = {The retinal photocoagulation is an established treatment method for different retinal diseases. The extent of the thermal coagulations depends strongly on the generated temperature increase. Until now the dosage is based on a pool of experience of the treating physicians as well as the appearance of the whitish lesions on the retina. The temperature course during photocoagulation can be measured in real-time by optoacoustics. A frequency-doubled Q-switched Nd:YLF laser (523nm, 75 ns) is used for optoacoustic excitation and a continuous-wave Nd:YAG laser (532nm) with adjustable irradiation time and power for heating of the fundus tissue. The onset of coagulation is determined by a photodiode that is placed directly behind enucleated porcine eyes, which served as a model. The onset of coagulation is observed clearly when scattering sets in. The required power for coagulation increases exponentially with decreasing irradiation time. The first results on rabbit eyes in vivo indicate that the onset of coagulation defined by just barely visibile lesions at a slit lamp sets in at an ED50 threshold temperature of 63°C for an irradiation time of 400 ms. In conclusion, optoacoustics can be used to determine temperatures during retinal laser treatments in real-time. This allows evaluating the time-temperature-dependence of retinal coagulation in vivo.},
       keywords = {AutoPhoN},
       url = {http://dx.doi.org/10.1117/12.831877},
       type = {Conference Proceedings},
    year = { 2009},
    url = { https://doi.org/10.1117/12.168030}
    }
    
  • Langejürgen, J and Schlott, K and Bever, M and Hausmann, K and Koinzer, S and Ptaszynski, L and Roider, J and Birngruber, R and Brinkmann, R: Dependence of optoacoustic transients on exciting laser parameters for real-time monitoring of retinal photocoagulation. pp. 73730K-73730K, 2009
    BibTeX Link
    @inproceedings{Langejürgen2009,
       author = {Langejürgen, J and Schlott, K and Bever, M and Hausmann, K and Koinzer, S and Ptaszynski, L and Roider, J and Birngruber, R and Brinkmann, R},
       title = {Dependence of optoacoustic transients on exciting laser parameters for real-time monitoring of retinal photocoagulation},
       pages = {73730K-73730K},
       note = {10.1117/12.831913},
       abstract = {The extent of retinal laser coagulations depends on the temperature increase at the fundus and the time of irradiation. Due to light scattering within the eye and variable fundus pigmentation the induced temperature increase and therefore the extent of the coagulations cannot be predicted solely from the laser parameters. We use optoacoustics to monitor the temperature rise in real-time in vivo (rabbit) and ex vivo (porcine eye) and to automatically control the coagulation strength. Continuous wave treatment laser radiation and pulsed probe laser light (1-1100 ns) are coupled into the same fibre and are imaged onto the retina by a laser slit lamp. The temperature dependent pressure waves are detected by an ultrasonic transducer embedded in a customary contact lens. Below the coagulation threshold the increase in acoustic amplitude due to thermal tissue expansion is up to 40 %. Best signal to noise ratios &gt; 10 are achieved with probe pulse durations of 1 to 75 ns. Further a time critical algorithm is developed which automatically ceases laser treatment when a certain preset coagulation strength is achieved. Coagulations with similar extent are obtained with this method in vitro and in vivo even when varying the power of the treatment laser by 50 %. These preliminary results are very promising, thus this method might be suitable for an automatic feedback controlled photocoagulation with adjustable coagulation strength.},
    url = {http://dx.doi.org/10.1117/12.831913},
       type = {Conference Proceedings},
    Year = { 2009}
    }
    

2002

  • Hüttmann, G. and Radt, B. and Serbin, J. and Lange, Björn I. and Birngruber, R.: High Precision Cell Surgery with Nanoparticles?. Med Laser Appl, no. 17, pp. 9-14, 2002
    BibTeX
    @article{Hüttmann2002,
       author = {Hüttmann, G. and Radt, B. and Serbin, J. and Lange,  Björn I. and Birngruber, R.},
       title = {High Precision Cell Surgery with Nanoparticles?},
       journal = {Med Laser Appl},
       volume = {17},
       pages = {9-14},
       year = {2002},
       type = {Journal Article}
    }
    

2001

  • Radt, Benno and Serbin, Jesper and Lange, Bjoern I. and Birngruber, Reginald and Huettmann, Gereon: Laser-generated micro- and nanoeffects: inactivation of proteins coupled to gold nanoparticles with nano- and picosecond pulses. no. 4433, pp. 16-24, SPIE, 2001
    BibTeX Link
    @inproceedings{Radt 2001,
       author = {Radt, Benno and Serbin, Jesper and Lange, Bjoern I. and Birngruber, Reginald and Huettmann, Gereon},
       title = {Laser-generated micro- and nanoeffects: inactivation of proteins coupled to gold nanoparticles with nano- and picosecond pulses},
       editor = {Reginald, Birngruber and Hubert van den, Bergh},
       publisher = {SPIE},
       volume = {4433},
       pages = {16-24},
    year = { 2001}
    URL = { https://doi.org/10.1117/12.446518}
    
    }
    
  • Lange, Bjoern I. and Radt, Benno and Huettmann, Gereon: Cr,Tm,Ho: YAG laser amplifier. no. 4267, pp. 169-174, SPIE, 2001
    BibTeX Link
    @inproceedings{Lange2001,
       author = {Lange, Bjoern I. and Radt, Benno and Huettmann, Gereon},
       title = {Cr,Tm,Ho: YAG laser amplifier},
       editor = {Richard, Scheps},
       publisher = {SPIE},
       volume = {4267},
       pages = {169-174},
    URL = {https://doi.org/10.1117/12.424616},
    Year = { 2001}
    }
    

002

  • Hüttmann, G. and Radt, B. and Serbin, J. and Lange, Björn.I. and Birngruber, R.: High Precision Cell Surgery with Nanoparticles?. Med Laser Appl, no. 17, pp. 9-14, 002
    BibTeX
    @article{Hüttmann,
       author = {Hüttmann, G. and Radt, B. and Serbin, J. and Lange, Björn.I. and Birngruber, R.},
       title = {High Precision Cell Surgery with Nanoparticles?},
       journal = {Med Laser Appl},
       volume = {17},
       pages = {9-14},
       year = {2002}
    }
    

001

  • Hüttmann, G. and Serbin, J. and Radt, B. and Lange, Björn I. and Birngruber, R.: Model system for investigating laser-induced subcellular microeffects.. Proc SPIE, no. 4257, pp. 398-409, 001
    BibTeX
    @article{Hüttmann,
       author = {Hüttmann, G. and Serbin, J. and Radt, B. and Lange, Björn I. and Birngruber, R.},
       title = {Model system for investigating laser-induced subcellular microeffects.},
       journal = {Proc SPIE},
       volume = {4257},
       pages = {398-409},
       year = {2001}
    }