2009
K
Schlott,
K
Hausmann,
S
Koinzer,
L
Ptaszynski, and
J
Roider,
Dependence of optoacoustic transients on exciting laser parameters for real-time monitoring of retinal photocoagulation, 2009. pp. 73730K-73730K.
Dependence of optoacoustic transients on exciting laser parameters for real-time monitoring of retinal photocoagulation, 2009. pp. 73730K-73730K.
Datei: | 12.831913 |
Bibtex: | ![]() @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 > 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} } |
A
Fritz,
L
Ptaszynski, and
H
Stoehr,
Dynamic of laser induced transient microbubble clusters, (BiOS), Conference on Biomedical Optics, Eds. Proc SPIE, 2009.
Dynamic of laser induced transient microbubble clusters, (BiOS), Conference on Biomedical Optics, Eds. Proc SPIE, 2009.
Datei: | abstract.cfm |
Bibtex: | ![]() @inproceedings{Fritz2009, author = {Fritz, A and Ptaszynski, L and Stoehr, H and Brinkmann, R}, title = {Dynamic of laser induced transient microbubble clusters}, editor = {(BiOS), Conference on Biomedical Optics}, publisher = {Proc SPIE}, type = {Conference Proceedings}, year = { 2009}, URL = { https://www.osapublishing.org/abstract.cfm?uri=ECBO-2009-7373_0D} } |
Kerstin
Schlott,
Jens
Langejürgen,
Marco
Bever,
Stefan
Koinzer, and
Ralf
Brinkmann,
Time resolved detection of tissue denaturation during retinal photocoagulation, 7373, Proc. SPIE, Eds. 2009. pp. 73730E-73730E.
Time resolved detection of tissue denaturation during retinal photocoagulation, 7373, Proc. SPIE, Eds. 2009. pp. 73730E-73730E.
Datei: | 12.168030 |
Bibtex: | ![]() @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} } |
Dierck
Hillmann, and
Peter
Koch,
Using nonequispaced fast Fourier transformation to process optical coherence tomography signals, Peter, E. Andersen and Brett, E. Bouma, Eds. SPIE, 2009. pp. 73720R.
Using nonequispaced fast Fourier transformation to process optical coherence tomography signals, Peter, E. Andersen and Brett, E. Bouma, Eds. SPIE, 2009. pp. 73720R.
Datei: | ECBO.2009.7372_0R |
Bibtex: | ![]() @inproceedings{Hillmann, author = {Hillmann, Dierck and Huttmann, Gereon and Koch, Peter}, title = {Using nonequispaced fast Fourier transformation to process optical coherence tomography signals}, editor = {Peter, E. Andersen and Brett, E. Bouma}, publisher = {SPIE}, volume = {7372}, pages = {73720R}, url = { https://doi.org/10.1364/ECBO.2009.7372_0R}, year = { 2009} } |
2008
Christian
Jirauschek,
Christoph M.
Eigenwillig,
Benjamin R.
Biedermann, and
Robert
Huber,
Fourier domain mode locking theory, in 2008 Conference on Lasers and Electro-Optics and 2008 Conference on Quantum Electronics and Laser Science , IEEE, Mai2008. pp. 1-2.
Fourier domain mode locking theory, in 2008 Conference on Lasers and Electro-Optics and 2008 Conference on Quantum Electronics and Laser Science , IEEE, Mai2008. pp. 1-2.
DOI: | 10.1109/CLEO.2008.4551638 |
Bibtex: | ![]() @INPROCEEDINGS{4571888, author={Jirauschek, Christian and Eigenwillig, Christoph and Biedermann, Benjamin and Huber, Robert}, booktitle={2008 Conference on Lasers and Electro-Optics and 2008 Conference on Quantum Electronics and Laser Science}, title={Fourier domain mode locking theory}, year={2008}, volume={}, number={}, pages={1-2}, abstract={We present a theoretical model for the recently developed Fourier domain mode locked (FDML) lasers. The good agreement with experiment provides valuable insights into the mechanism of FDML operation.}, keywords={}, doi={10.1109/CLEO.2008.4551638}, ISSN={}, month={May},} |
Christoph M.
Eigenwillig,
Benjamin R.
Biedermann, and
Robert
Huber,
Optical coherence tomography imaging with k-space linear Fourier Domain Mode Locked lasers, in 2008 Conference on Lasers and Electro-Optics and 2008 Conference on Quantum Electronics and Laser Science , IEEE, Mai2008. pp. 1-2.
Optical coherence tomography imaging with k-space linear Fourier Domain Mode Locked lasers, in 2008 Conference on Lasers and Electro-Optics and 2008 Conference on Quantum Electronics and Laser Science , IEEE, Mai2008. pp. 1-2.
DOI: | 10.1109/CLEO.2008.4551011 |
Bibtex: | ![]() @INPROCEEDINGS{4571261, author={Eigenwillig, Christoph and Biedermann, Benjamin and Huber, Robert}, booktitle={2008 Conference on Lasers and Electro-Optics and 2008 Conference on Quantum Electronics and Laser Science}, title={Optical coherence tomography imaging with k-space linear fourier domain mode locked lasers}, year={2008}, volume={}, number={}, pages={1-2}, abstract={We report on a Fourier Domain Mode Locked wavelength swept laser source with a highly linear time-frequency sweep characteristic and demonstrate OCT imaging without k-space resampling prior to Fourier transformation with this source.}, keywords={}, doi={10.1109/CLEO.2008.4551011}, ISSN={}, month={May},} |
Desmond C.
Adler,
Yu
Chen,
Robert
Huber,
Joseph M.
Schmitt,
James
Connolly, and
James G.
Fujimoto,
In vivo endomicroscopy using three-dimensional optical coherence tomography and Fourier domain mode locked lasers, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XII , Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin, Eds. SPIE, Mä.2008. pp. 684708.
In vivo endomicroscopy using three-dimensional optical coherence tomography and Fourier domain mode locked lasers, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XII , Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin, Eds. SPIE, Mä.2008. pp. 684708.
DOI: | 10.1117/12.761850 |
Bibtex: | ![]() @inproceedings{10.1117/12.761850, author = {Desmond C. Adler and Yu Chen and Robert Huber and Joseph Schmitt and James Connolly and James G. Fujimoto}, title = {{In vivo endomicroscopy using three-dimensional optical coherence tomography and Fourier domain mode locked lasers}}, volume = {6847}, booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XII}, editor = {Joseph A. Izatt and James G. Fujimoto and Valery V. Tuchin}, organization = {International Society for Optics and Photonics}, publisher = {SPIE}, pages = {684708}, abstract = {We report an endoscopic optical coherence tomography (OCT) system based on a Fourier Domain Mode Locked (FDML) laser, a novel data acquisition (DAQ) system with optical frequency clocking, and a high-speed spiralscanning fiber probe. The system is capable of acquiring three-dimensional (3D) in vivo datasets at 100,000 axial lines/s and 50 frames/s, enabled by the high sweep rates of the FDML laser and the efficient data processing of the DAQ system. This high imaging rate allows densely-sampled 3D datasets to be acquired, giving a resolvable feature size of 9 &mgr;m x 20 &mgr;m x 7 &mgr;m (transverse x longitudinal x axial, XYZ). In vivo 3D endomicroscopy is demonstrated in the rabbit colon, where individual colonic crypts are clearly visualized and measured. With further improvements in DAQ technology, the imaging speed will be scalable to the hundreds of thousands of axial lines/s supported by FDML lasers.}, keywords = {Optical coherence tomography, Endoscopic microscopy, Fourier Domain Mode Locked lasers, FDML, Three dimensional microscopy, In vivo microscopy, Biomedical optics, Swept source optical coherence tomography}, year = {2008}, doi = {10.1117/12.761850}, URL = {https://doi.org/10.1117/12.761850} } |
Yu
Chen,
Joseph M.
Schmitt,
James
Connolly, and
James G.
Fujimoto,
In vivo endomicroscopy using three-dimensional optical coherence tomography and {Fourier} domain mode locked lasers, in Biomedical Optics (BiOS) 2008 , Izatt, Joseph A. and Fujimoto, James G. and Tuchin, Valery V., Eds. International Society for Optics and Photonics, Feb.2008. pp. 684708--684708--7.
In vivo endomicroscopy using three-dimensional optical coherence tomography and {Fourier} domain mode locked lasers, in Biomedical Optics (BiOS) 2008 , Izatt, Joseph A. and Fujimoto, James G. and Tuchin, Valery V., Eds. International Society for Optics and Photonics, Feb.2008. pp. 684708--684708--7.
DOI: | 10.1117/12.761850 |
Datei: | proceeding.aspx |
Bibtex: | ![]() @InProceedings{HU_2008_Adlera, Title = {{In vivo endomicroscopy using three-dimensional optical coherence tomography and {Fourier} domain mode locked lasers}}, Author = {Adler, Desmond C. and Chen, Yu and Huber, Robert and Schmitt, Joseph and Connolly, James and Fujimoto, James G.}, Booktitle = {Biomedical Optics (BiOS) 2008}, Year = {2008}, Editor = {Izatt, Joseph A. and Fujimoto, James G. and Tuchin, Valery V.}, Month = feb, Pages = {684708--684708--7}, Publisher = {International Society for Optics and Photonics}, Doi = {10.1117/12.761850}, Url = {http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1326810\&resultClick=1} } |
Philip
Steven, and
Norbert
Koop,
Confocal microscopy versus two-photon microscopy: imaging of ocular surface pathologies, Ammasi, Periasamy and Peter, T. C. So, Eds. SPIE, 2008. pp. 686023.
Confocal microscopy versus two-photon microscopy: imaging of ocular surface pathologies, Ammasi, Periasamy and Peter, T. C. So, Eds. SPIE, 2008. pp. 686023.
T.
Just,
E.
Lankenau,
G.
Huettmann, and
H.W.
Pau,
Optical coherence tomography as a guide for cochlear implant surgery, in Progress in Biomedical Optics and Imaging , Nikiforos, K. and Bernard, C. and Haishan, Z., Eds. SPIE 6842, 2008. pp. F1-F6.
Optical coherence tomography as a guide for cochlear implant surgery, in Progress in Biomedical Optics and Imaging , Nikiforos, K. and Bernard, C. and Haishan, Z., Eds. SPIE 6842, 2008. pp. F1-F6.
Datei: | 12.771446 |
Bibtex: | ![]() @inproceedings{Just-2008, author = {Just, T. and Lankenau, E. and Huettmann, G. and Pau, H.W.}, title = {Optical coherence tomography as a guide for cochlear implant surgery}, booktitle = {Progress in Biomedical Optics and Imaging}, editor = {Nikiforos, K. and Bernard, C. and Haishan, Z.}, publisher = {SPIE 6842}, pages = {F1-F6}, url = { https://doi.org/10.1117/12.771446}, year = { 2008} } |
2007
Robert
Huber,
Vivek J.
Srinivasan,
Desmond C.
Adler,
Iwona
Gorczynska, and
James G.
Fujimoto,
Fourier Domain Mode Locking (FDML) in the non-zero dispersion regime: A laser for ultrahigh-speed retinal OCT imaging at 236kHz line rate, in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies , Optica Publishing Group, Mai2007. pp. CThAA5.
Fourier Domain Mode Locking (FDML) in the non-zero dispersion regime: A laser for ultrahigh-speed retinal OCT imaging at 236kHz line rate, in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies , Optica Publishing Group, Mai2007. pp. CThAA5.
DOI: | 10.1109/CLEO.2007.4452681 |
Bibtex: | ![]() @inproceedings{Huber:07, author = {Robert Huber and Vivek J. Srinivasan and Desmond C. Adler and I. Gorczynska and James G. Fujimoto}, booktitle = {Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies}, journal = {Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies}, keywords = {General physics; General science; Fourier domain mode locking; Image quality; In vivo imaging; Laser sources; Ophthalmic imaging; Optical coherence tomography}, pages = {CThAA5}, publisher = {Optica Publishing Group}, title = {Fourier Domain Mode Locking (FDML) in the non-zero dispersion regime: A laser for ultrahigh-speed retinal OCT imaging at 236kHz line rate}, year = {2007}, url = {https://opg.optica.org/abstract.cfm?URI=CLEO-2007-CThAA5}, abstract = {Fourier Domain Mode Locking (FDML) in the 1070nm wavelength range is investigated. Problems, design rules and the performance of an FDML laser with a dispersive cavity are discussed. Retinal OCT imaging at 236kHz is demonstrated.}, } |
Desmond C.
Adler,
Robert
Huber, and
James G.
Fujimoto,
Optical coherence tomography phase microscopy using buffered fourier domain mode locked (FDML) lasers at up to 370,000 lines per second, in 2007 Conference on Lasers and Electro-Optics (CLEO) , IEEE, Mai2007. pp. 1-2.
Optical coherence tomography phase microscopy using buffered fourier domain mode locked (FDML) lasers at up to 370,000 lines per second, in 2007 Conference on Lasers and Electro-Optics (CLEO) , IEEE, Mai2007. pp. 1-2.
DOI: | 10.1109/CLEO.2007.4452406 |
Bibtex: | ![]() @INPROCEEDINGS{4452406, author={Adler, Desmond C. and Huber, Robert and Fujimoto, James G.}, booktitle={2007 Conference on Lasers and Electro-Optics (CLEO)}, title={Optical Coherence Tomography Phase Microscopy Using Buffered Fourier Domain Mode Locked (FDML) Lasers at up to 370,000 Lines per Second}, year={2007}, volume={}, number={}, pages={1-2}, abstract={Buffered FDML lasers are applied for phase-sensitive sub-nanometer OCT phase microscopy and dynamic surface displacement measurements at speeds up to 370,000 axial lines per second. Excellent phase stability is demonstrated at high speeds.}, keywords={}, doi={10.1109/CLEO.2007.4452406}, ISSN={2160-9004}, month={May},} |
Robert
Huber,
Desmond C.
Adler,
Vivek J.
Srinivasan,
Iwona
Gorczynska, and
James G.
Fujimoto,
Fourier domain mode-locked (FDML) lasers at 1050 nm and 202,000 sweeps per second for OCT retinal imaging, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI , James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin, Eds. SPIE, Feb.2007. pp. 642907.
Fourier domain mode-locked (FDML) lasers at 1050 nm and 202,000 sweeps per second for OCT retinal imaging, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI , James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin, Eds. SPIE, Feb.2007. pp. 642907.
DOI: | 10.1117/12.704084 |
Bibtex: | ![]() @inproceedings{10.1117/12.704084, author = {Robert A. Huber and Desmond C. Adler and Vivek J. Srinivasan and Iwona M Gorczynska and James G. Fujimoto}, title = {{Fourier domain mode-locked (FDML) lasers at 1050 nm and 202,000 sweeps per second for OCT retinal imaging}}, volume = {6429}, booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI}, editor = {James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin}, organization = {International Society for Optics and Photonics}, publisher = {SPIE}, pages = {642907}, abstract = {Retinal imaging ranks amongst the most important clinical applications for optical coherence tomography (OCT) [1, 2]. The recent demonstration of increased sensitivity [3-6] in Fourier Domain detection [7, 8] has opened the way for dramatically higher imaging speeds, up to axial scan rates of several tens of kilohertz. However, these imaging speeds are still not sufficient for high density 3D datasets and a further increase to several hundreds of kilohertz is necessary. In this paper we demonstrate a swept laser source at 1050 nm with a sweep rate of 202 kHz. The laser source provides ~10 mW average output power, up to 60 nm total sweep range and a sensitivity roll off of less than 10 dB over 4 mm. In vivo 2D and 3D imaging of the human retina at a record axial scan rate of 101 kHz is demonstrated. These results suggest that swept source OCT has the potential to significantly outperform spectral/Fourier domain OCT for ophthalmic imaging applications in the future.}, keywords = {tunable laser, optical coherence tomography, Fourier domain mode locking, swept source, OCT, FDML, retinal imaging, ophthalmic imaging}, year = {2007}, doi = {10.1117/12.704084}, URL = {https://doi.org/10.1117/12.704084} } |
Desmond C.
Adler,
Robert
Huber, and
James G.
Fujimoto,
Phase-sensitive optical coherence tomography using buffered Fourier domain mode-locked lasers at up to 370,000 scans per second, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI , James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin, Eds. SPIE, Feb.2007. pp. 64291L.
Phase-sensitive optical coherence tomography using buffered Fourier domain mode-locked lasers at up to 370,000 scans per second, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI , James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin, Eds. SPIE, Feb.2007. pp. 64291L.
DOI: | 10.1117/12.704128 |
Bibtex: | ![]() @inproceedings{10.1117/12.704128, author = {Desmond C. Adler and Robert Huber and James G. Fujimoto}, title = {{Phase-sensitive optical coherence tomography using buffered Fourier domain mode-locked lasers at up to 370,000 scans per second}}, volume = {6429}, booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine XI}, editor = {James G. Fujimoto and Joseph A. Izatt and Valery V. Tuchin}, organization = {International Society for Optics and Photonics}, publisher = {SPIE}, pages = {64291L}, abstract = {Phase sensitive optical coherence tomography (OCT) can be used to obtain sub-nanometer displacement measurements of biological and non-biological samples. This technique has many applications, including detection of small amplitude surface motion, and high axial resolution OCT phase microscopy. Doppler OCT is another type of phase sensitive imaging, where differential phase measurements are used to detect fluid flow in biological specimens. For all types of phase sensitive OCT, a light source with low phase noise is required in order to provide good displacement sensitivity. High speed imaging is also necessary in order to minimize motion artifacts and enable the detection of fast transient events. In this manuscript, buffered Fourier Domain Mode Locked (FDML) lasers are demonstrated for ultrahigh-speed phase sensitive OCT detection. The lasers are operated at sweep speeds of 42, 117, and 370 kHz, and displacement sensitivities of 39, 52, and 102 pm are achieved, respectively. These displacement sensitivities are comparable to spectrometer-based phase sensitive OCT systems, but acquisition speeds 1.4 - 13x faster are possible using buffered FDML lasers. An additional factor of √2 improvement in noise performance is observed for differential phase measurements, which has important implications for Doppler OCT. Dynamic measurements of rapid, small-amplitude piezoelectric transducer motion are demonstrated. In general, buffered FDML lasers provide excellent displacement sensitivities at extremely high sweep speeds for phase sensitive OCT measurements.}, keywords = {optical coherence tomography, OCT, optical coherence phase microscopy, swept source phase microscopy, doppler optical coherence tomography, frequency swept lasers, Fourier Domain Mode Locked lasers, FDML}, year = {2007}, doi = {10.1117/12.704128}, URL = {https://doi.org/10.1117/12.704128} } |
Andreas
Fritz,
Lars
Ptaszynski,
Hardo
Stoehr, and
Ralf
Brinkmann,
Dynamics and detection of laser induced microbubbles in the retinal pigment epithelium (RPE), 2007. pp. 66321C-66321C-11.
Dynamics and detection of laser induced microbubbles in the retinal pigment epithelium (RPE), 2007. pp. 66321C-66321C-11.
Datei: | 12.728344 |
Bibtex: | ![]() @inproceedings{Fritz2007, author = {Fritz, Andreas and Ptaszynski, Lars and Stoehr, Hardo and Brinkmann, Ralf}, title = {Dynamics and detection of laser induced microbubbles in the retinal pigment epithelium (RPE)}, volume = {6632}, pages = {66321C-66321C-11}, note = {10.1117/12.728344}, abstract = {Selective Retina Treatment (SRT) is a new method to treat eye diseases associated with disorders of the RPE. Selective RPE cell damage is achieved by applying a train of 1.7 μs laser pulses at 527 nm. The treatment of retinal diseases as e.g. diabetic maculopathy (DMP), is currently investigated within clinical studies, however 200 ns pulse durations are under investigation. Transient micro bubbles in the retinal pigment epithelium (RPE) are expected to be the origin of cell damage due to irradiation with laser pulses shorter than 50 μs. The bubbles emerge at the strongly absorbing RPE melanosomes. Cell membrane disruption caused by the transient associated volume increase is expected to be the origin of the angiographically observed RPE leakage. We investigate micro bubble formation and dynamics in porcine RPE using pulse durations of 150 ns. A laser interferometry system at 830 nm with the aim of an online dosimetry control for SRT was developed. Bubble formation was detected interferometrically and by fast flash photography. A correlation to cell damage observed with a vitality stain is found. A bubble detection algorithm is presented.}, url = {http://dx.doi.org/10.1117/12.728344}, type = {Conference Proceedings} } |
Katharina
Herrmann,
Christian
Flöhr,
Jens
Stalljohann,
Gabriela
Apiou-Sbirlea,
Jochen
Kandulla, and
Ralf
Brinkmann,
Influence of choroidal perfusion on retinal temperature increase during retinal laser treatments, 2007. pp. 66321D-66321D-7.
Influence of choroidal perfusion on retinal temperature increase during retinal laser treatments, 2007. pp. 66321D-66321D-7.
Datei: | 12.728222 |
Bibtex: | ![]() @inproceedings{Herrmann2007, author = {Herrmann, Katharina and Flöhr, Christian and Stalljohann, Jens and Apiou-Sbirlea, Gabriela and Kandulla, Jochen and Birngruber, Reginald and Brinkmann, Ralf}, title = {Influence of choroidal perfusion on retinal temperature increase during retinal laser treatments}, volume = {6632}, pages = {66321D-66321D-7}, note = {10.1117/12.728222}, abstract = {In most retinal laser treatments the therapeutic effect is initiated by a transient temperature increase at and around the retinal pigment epithelium (RPE). Especially in long exposure time treatments like Transpupillary Thermotherapy (TTT) choroidal perfusion has a strong influence on the realized temperature at the fundus. The fundus blood circulation and therefore the heat dissipation is influenced by the intraocular pressure (IOP), which is investigated in the study presented here. In order to reduce the choroidal perfusion, the IOP is increased by injection of physiological saline solution into the eye of anaesthetized rabbits. The fundus is irradiated with 3.64 W/cm2 by means of a TTT-laser (λ = 810 nm) for t = 20 s causing a retinal temperature increase. Realtime temperature determination at the irradiated spot is achieved by a non invasive optoacoustic technique. Perfusion can be reduced by increasing IOP, which leads to different temperature increases when irradiating the retina. This should be considered for long time laser treatments.}, url = {http://dx.doi.org/10.1117/12.728222}, type = {Conference Proceedings}, year = { 2007} } |
Hardo
Stoehr,
Lars
Ptaszynski,
Andreas
Fritz, and
Ralf
Brinkmann,
Interferometric optical online dosimetry for selective retina treatment (SRT), 2007. pp. 642619-642619-7.
Interferometric optical online dosimetry for selective retina treatment (SRT), 2007. pp. 642619-642619-7.
Datei: | 12.708521 |
Bibtex: | ![]() @inproceedings{Stoehr2007-1, author = {Stoehr, Hardo and Ptaszynski, Lars and Fritz, Andreas and Brinkmann, Ralf}, title = {Interferometric optical online dosimetry for selective retina treatment (SRT)}, volume = {6426}, pages = {642619-642619-7}, note = {10.1117/12.708521}, abstract = {In selective retina treatment (SRT) spatial confined tissue damage in the absorbing retinal pigment epithelium (RPE) is obtained by applying microsecond laser pulses. The damage in the RPE is caused by transient microbubbles forming around the laser heated melanin granules inside the cells. For treatment of RPE related diseases, SRT is thought to share the therapeutic benefits of conventional photocoagulation but without affecting the photoreceptors. A drawback for effective clinical SRT is that the laser-induced lesions are ophthalmoscopically invisible. Therefore, a real-time feedback system for dosimetry is demanded in order to avoid undertreatment or unwanted collateral damage to the adjacent tissue. We develop a dosimetry system which uses optical interferometry for the detection of the transient microbubbles. The system is based on an optical fiber interferometer which is operated with a laser diode at 830nm. We present current results obtained with porcine RPE explants in vitro and complete porcine eye globes ex vivo.}, url = {http://dx.doi.org/10.1117/12.708521}, type = {Conference Proceedings}, Year = { 2007} } |
Xiaochao
Qu,
Koop
Norbert,
Zheng
Li,
Jing
Wang, and
Zhenxi
Zhang,
Multiphoton fluorescence lifetime imaging of Karpas 299 cells using ACT1 antibody conjugated gold nanoparticles, 2007. pp. 66301C-66301C-8.
Multiphoton fluorescence lifetime imaging of Karpas 299 cells using ACT1 antibody conjugated gold nanoparticles, 2007. pp. 66301C-66301C-8.
Datei: | 12.728239 |
Bibtex: | ![]() @inproceedings{Qu2007, author = {Qu, Xiaochao and Norbert, Koop and Li, Zheng and Wang, Jing and Zhang, Zhenxi and Hüttmann, Gereon}, title = {Multiphoton fluorescence lifetime imaging of Karpas 299 cells using ACT1 antibody conjugated gold nanoparticles}, volume = {6630}, pages = {66301C-66301C-8}, note = {10.1117/12.728239}, abstract = {Due to the unique optical properties, gold nanoparticles (NPs) can play a useful role in biological cellular imaging as biological probes. Using multiphoton microscopy and fluorescence lifetime imaging (FLIM) system, we recorded the images of Karpas 299 cells incubated without, or with gold NPs, and ACT1 antibodies conjugated with gold NPs. From the FLIM, we can easily discriminate the difference among different experiment conditions due to the distinct lifetime between cells and gold NPs. Our results present that nonconjugated gold NPs are accumulated inside cells, but conjugated gold NPs bind homogeneously and specifically to the surface of cancer cells. For single Karpas 299 cells, the signal is very week when the excitation power is about 10mw; while the power is approximately 28 mw, a very sharp cell imaging can be obtained. For the Karpas 299 incubated with ACT1 conjugated gold NPs, while the excitation power is 10mw, gold NPs have clear fluorescence signal so that the profile of cells can be detected; Signal of gold NPs is very strong when the power arrived in 20mw. These results suggest that the multiphoton lifetime imaging of antibody conjugated gold NPs can support a useful method in diagnosis of cancer.}, url = {http://dx.doi.org/10.1117/12.728239}, type = {Conference Proceedings}, year = { 2007} } |
Kerstin
Schlott,
Jens
Stalljohann,
Benjamin
Weber,
Jochen
Kandulla,
Katharina
Herrmann, and
Ralf
Brinkmann,
Optoacoustic online temperature determination during retinal laser photocoagulation, 2007. pp. 66321B-66321B-8.
Optoacoustic online temperature determination during retinal laser photocoagulation, 2007. pp. 66321B-66321B-8.
Datei: | 12.728291 |
Bibtex: | ![]() @inproceedings{Schlott2007, author = {Schlott, Kerstin and Stalljohann, Jens and Weber, Benjamin and Kandulla, Jochen and Herrmann, Katharina and Birngruber, Reginald and Brinkmann, Ralf}, title = {Optoacoustic online temperature determination during retinal laser photocoagulation}, volume = {6632}, pages = {66321B-66321B-8}, note = {10.1117/12.728291}, abstract = {Retinal photocoagulation is an established treatment of different retinal diseases. The treatment relies on a short, local heating of the tissue which induces a denaturation. The resulting scar formation may for example prevent the further detachment of the retina. The extent of the coagulation is besides other parameters mostly dependent on the induced temperature increase. However, until today a temperature based dosimetry for photocoagulation does not exist. The dosage is rather based on the experience of the treating physicians to achieve visible whitish lesions on the retina. In this work a technique is presented, which allows an online temperature monitoring during photocoagulation. If an absorbing material is irradiated with short laser pulses, a thermoelastic expansion of the absorber induces an acoustic wave. Its amplitude is dependent on the temperature of the absorber. For analyzing the applicability of the optoacoustic temperature determination for dosimetry, measurements were performed on enucleated porcine eye globes. The pressure transients are detected by an ultrasonic transducer, which is embedded in an ophthalmologic contact lens. As long as no strong lesions occur, the determined temperatures are almost proportional to the power of the treatment laser. Using a spot diameter of 200 μm and different laser powers, the temperature rise at the end of the 400 ms irradiation was found to be approximately 0.16 °C/mW. The onset of the denaturation was observed around 50°C. The far aim of this project is an automatic regulation of the treatment laser onto a desired temperature course.}, url = {http://dx.doi.org/10.1117/12.728291}, type = {Conference Proceedings}, year = { 2007} } |
S
Tedsen, and
K
Herrmann,
Partial kidney resection by use of a 1,94 µm thulium fiber laser, in Proc ECBO , SPIE, 2007.
Partial kidney resection by use of a 1,94 µm thulium fiber laser, in Proc ECBO , SPIE, 2007.
Datei: | 978-3-540-68764-1_72 |
Bibtex: | ![]() @inproceedings{Theisen-Kunde2007, author = {Theisen-Kunde, D and Tedsen, S and Danicke, V and Herrmann, K and Brinkmann, R}, title = {Partial kidney resection by use of a 1,94 µm thulium fiber laser}, booktitle = {Proc ECBO}, series = {Therapeutic Laser Applications and Laser-Tissue Interactions}, publisher = {SPIE}, volume = {6632}, type = {Conference Proceedings}, year = { 2007}, url = { https://doi.org/10.1007/978-3-540-68764-1_72} } |
2006
Robert
Huber,
Maciej
Wojtkowski, and
James G.
Fujimoto,
Fourier domain mode locking (FDML): Three-dimensional OCT imaging at 906 frames per second, in 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference , IEEE, Mai2006. pp. 1-2.
Fourier domain mode locking (FDML): Three-dimensional OCT imaging at 906 frames per second, in 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference , IEEE, Mai2006. pp. 1-2.
DOI: | 10.1109/CLEO.2006.4627914 |
Bibtex: | ![]() @INPROCEEDINGS{4627914, author={Huber, R. and Wojtkowski, M. and Fujimoto, J. G.}, booktitle={2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference}, title={Fourier Domain Mode Locking (FDML): Three-dimensional OCT imaging at 906 frames per second}, year={2006}, volume={}, number={}, pages={1-2}, abstract={Fourier domain mode locking is a new operation regime of lasers. Highly chirped frequency swept waveforms rather than short pulses are generated. The mechanism and its application for ultrahigh-speed biomedical OCT imaging are discussed.}, keywords={}, doi={10.1109/CLEO.2006.4627914}, ISSN={2160-9004}, month={May},} |
Kenji
Taira,
Robert
Huber,
Maciej
Wojtkowski, and
James G.
Fujimoto,
Fourier domain mode-locked lasers for swept source OCT imaging at up to 290 kHz scan rates, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine X , Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto, Eds. SPIE, Feb.2006. pp. 60790U.
Fourier domain mode-locked lasers for swept source OCT imaging at up to 290 kHz scan rates, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine X , Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto, Eds. SPIE, Feb.2006. pp. 60790U.
DOI: | 10.1117/12.648880 |
Bibtex: | ![]() @inproceedings{10.1117/12.648880, author = {R. Huber and K. Taira and M. Wojtkowski and J. G. Fujimoto}, title = {{Fourier domain mode-locked lasers for swept source OCT imaging at up to 290 kHz scan rates}}, volume = {6079}, booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine X}, editor = {Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto}, organization = {International Society for Optics and Photonics}, publisher = {SPIE}, pages = {60790U}, abstract = {A new type of laser operation, Fourier Domain Mode Locking (FDML), is demonstrated for high performance, frequency swept light sources. FDML achieves superior sweep speeds, coherence lengths and bandwidths compared to standard bulk or fiber lasers. At 1300 nm a sweep range up to 145 nm, up to 4 cm delay length, and sweep rates up to 290 kHz were achieved. This light source is demonstrated for swept source OCT imaging.}, keywords = {Fourier Domain Mode Locking, swept laser, tunable laser, wavelength agile, optical coherence tomography, spectral domain, Fourier domain, fiber laser}, year = {2006}, doi = {10.1117/12.648880}, URL = {https://doi.org/10.1117/12.648880} } |
Laura A.
Kranendonk,
Joachim W.
Walewski,
Scott T.
Sanders,
Robert
Huber, and
James G.
Fujimoto,
Measurements of Gas Temperature in an HCCI Engine by Use of a Fourier-Domain Mode-Locking Laser, in Laser Applilcations to Chemical, Security and Environmental Analysis , Optica Publishing Group, Feb.2006. pp. TuB2.
Measurements of Gas Temperature in an HCCI Engine by Use of a Fourier-Domain Mode-Locking Laser, in Laser Applilcations to Chemical, Security and Environmental Analysis , Optica Publishing Group, Feb.2006. pp. TuB2.
DOI: | 10.1364/LACSEA.2006.TuB2 |
Bibtex: | ![]() @inproceedings{Kranendonk:06, author = {Laura A. Kranendonk and Joachim W. Walewski and Scott T. Sanders and Robert Huber and James G. Fujimoto}, booktitle = {Laser Applilcations to Chemical, Security and Environmental Analysis}, journal = {Laser Applilcations to Chemical, Security and Environmental Analysis}, keywords = {Lasers and laser optics; Diode lasers; Lasers, tunable; Laser operation; Laser sensors; Lasers; Mode locking; Spontaneous emission; Tunable diode lasers}, pages = {TuB2}, publisher = {Optica Publishing Group}, title = {Measurements of gas temperature in an HCCI engine by use of a Fourier-domain mode-locking laser}, year = {2006}, url = {https://opg.optica.org/abstract.cfm?URI=LACSEA-2006-TuB2}, doi = {10.1364/LACSEA.2006.TuB2}, abstract = {Initial measurements of water vapor temperature by use of a Fourier-domain mode-locking laser were performed in a homogenous charge compression ignition engine. We assessed the potential of this FDML laser in combustion applications.}, } |
Alfred
Vogel,
J.
Noack,
N.
Linz,
S.
Freidank, and
G.
Paltauf,
Femtosecond laser nanosurgery of biological cells and tissues, in 4th International Congress on Laser Advanced Materials Processing , 2006.
Femtosecond laser nanosurgery of biological cells and tissues, in 4th International Congress on Laser Advanced Materials Processing , 2006.
Datei: | download |
Bibtex: | ![]() @inproceedings{Vogel-2006, author = {Vogel, A. and Noack, J. and Hüttmann, G. and Linz, N. and Freidank, S. and Paltauf, G.}, title = {Femtosecond laser nanosurgery of biological cells and tissues}, booktitle = {4th International Congress on Laser Advanced Materials Processing}, Year = { 2006}, URL = { http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.713.4169&rep=rep1&type=pdf} } |
Julien
Sandeau,
Georges
Caillibotte,
Jochen
Kandulla, and
Gabriela
Apiou-Sbirlea,
Modeling of conductive and convective heat transfers in retinal laser treatments, 2006. pp. 61381A-61381A-9.
Modeling of conductive and convective heat transfers in retinal laser treatments, 2006. pp. 61381A-61381A-9.
Datei: | 12.673494 |
Bibtex: | ![]() @inproceedings{Sandeau2006, author = {Sandeau, Julien and Caillibotte, Georges and Kandulla, Jochen and Birngruber, Reginald and Apiou-Sbirlea, Gabriela}, title = {Modeling of conductive and convective heat transfers in retinal laser treatments}, volume = {6138}, pages = {61381A-61381A-9}, note = {10.1117/12.673494}, abstract = {Tumor thermo treatment such as photodynamic therapy (PDT) or transpupillary thermotherapy (TTT) deal with long term and large laser spot exposures. The induced temperature increase is not exactly known [1]. Under these conditions convective heat transfers due to the blood flow in the choroid and the choriocapillaris must be considered in addition to the usually calculated heat conduction. From an existing analytical model defining a unique convective term for the whole fundus irradiated with Gaussian irradiance distribution lasers [2], we developed a numerical one allowing a precise modelling of convection and calculating heating evolution and temperature profiles of the fundus of the eye. The aim of this study is to present the modelling and several comparisons between experimental results [3] and numerical ones concerning the convective heat transfers inside the fundus of the eye.}, url = {http://dx.doi.org/10.1117/12.673494}, type = {Conference Proceedings}, year = { 2006} } |