liu.seSearch for publications in DiVA
Change search
Link to record
Permanent link

Direct link
BETA
Antonsson, Johan
Publications (10 of 18) Show all publications
Antonsson, J., Eriksson, O., Blomstedt, P., Bergenheim, T., Hariz, M., Richter, J., . . . Wårdell, K. (2008). Diffuse reflectance spectroscopy measurements for tissue type discrimination during deep brain stimulation. Journal of neural engineering, 5(2), 185-190
Open this publication in new window or tab >>Diffuse reflectance spectroscopy measurements for tissue type discrimination during deep brain stimulation
Show others...
2008 (English)In: Journal of neural engineering, ISSN 1741-2560, Vol. 5, no 2, p. 185-190Article in journal (Refereed) Published
Abstract [en]

Diffuse reflectance spectroscopy as a method for improving intracerebral guidance during functional neurosurgery has been investigated. An optical probe was developed for measurements during stereotactic and functional neurosurgery in man. The aim of the study was to investigate the spectral differences between white and grey matter and between white matter and functional targets. Diffuse reflectance spectroscopy measurements in ten patients were recorded at incremental steps towards and in three different functional targets (STN, GPi and Zi). The recorded spectra along the trajectory were sorted into white or grey matter, based on preoperative MRI images or the recorded spectral shape and intensity. The difference between tissue types was calculated as a quotient. Significant intensity differences between white and grey matter were found to be at least 14% (p < 0.05) and 20% (p < 0.0001) for MRI and spectral-sorted data respectively. The reflectance difference between white matter and the functional targets of GPi was higher than for STN and Zi. The results indicate that diffuse reflectance spectroscopy has a potential to be developed to a suitable complement to other intracerebral guidance methods.

National Category
Engineering and Technology
Identifiers
urn:nbn:se:liu:diva-14235 (URN)10.1088/1741-2560/5/2/009 (DOI)000257253800009 ()18460743 (PubMedID)2-s2.0-48949118315 (Scopus ID)
Available from: 2007-01-26 Created: 2007-01-26 Last updated: 2017-02-10Bibliographically approved
Wårdell, K., Fors, C., Antonsson, J. & Eriksson, O. (2007). A laser Doppler system for intracerebral measurements during stereotactic neurosurgery. In: Engineering in Medicine and Biology Society, 2007. EMBS 2007: . Paper presented at 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS 2007), 22-26 August 2007, Lyon, France (pp. 4083-4086). IEEE
Open this publication in new window or tab >>A laser Doppler system for intracerebral measurements during stereotactic neurosurgery
2007 (English)In: Engineering in Medicine and Biology Society, 2007. EMBS 2007, IEEE , 2007, p. 4083-4086Conference paper, Published paper (Refereed)
Abstract [en]

A laser Doppler system for intracerebral measurements during stereotactic and functional neurosurgery is presented. The system comprises a laser Doppler perfusion monitor, an optical probe adapted for the Leksellreg stereotactic system and a personal computer with software for acquisition, data analysis and presentation. The software makes it possible to present both the perfusion and the total backscattered light intensity (TLI) in real-time. During intracerebral measurements, the perfusion signal records the tissue's microcirculation whereas the TLI signal may be used to distinguish between grey and white matter. Evaluation of the system has been done during stereotactic neurosurgery in relation to implantation of deep brain stimulation electrodes. Measurements were made along trajectories towards targets in the deep brain structure as well as in pre-calculated target areas. The measurements show that the system has a potential to be used for intracerebral guidance but further evaluation of the technique is needed.

Place, publisher, year, edition, pages
IEEE, 2007
Series
IEEE Engineering in Medicine and Biology Society. Conference Proceedings, ISSN 1557-170X
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-38409 (URN)10.1109/IEMBS.2007.4353231 (DOI)44245 (Local ID)9781424407873 (ISBN)9781424407880 (ISBN)44245 (Archive number)44245 (OAI)
Conference
29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS 2007), 22-26 August 2007, Lyon, France
Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-02-17Bibliographically approved
Wårdell, K., Blomstedt, P., Richter, J., Antonsson, J., Eriksson, O., Zsigmond, P., . . . Hariz, M. (2007). Intracerebral microvascular measurements during deep brain stimulation implantation using laser doppler perfusion monitoring. Stereotactic and Functional Neurosurgery, 85(6), 279-286
Open this publication in new window or tab >>Intracerebral microvascular measurements during deep brain stimulation implantation using laser doppler perfusion monitoring
Show others...
2007 (English)In: Stereotactic and Functional Neurosurgery, ISSN 1011-6125, E-ISSN 1423-0372, Vol. 85, no 6, p. 279-286Article in journal (Refereed) Published
Abstract [en]

The aim of the study was to investigate if laser Doppler perfusion monitoring (LDPM) can be used in order to differentiate between gray and white matter and to what extent microvascular perfusion can be recorded in the deep brain structures during stereotactic neurosurgery. An optical probe constructed to fit in the Leksell® Stereotactic System was used for measurements along the trajectory and in the targets (globus pallidus internus, subthalamic nucleus, zona incerta, thalamus) during the implantation of deep brain stimulation leads (n = 22). The total backscattered light intensity (TLI) reflecting the grayness of the tissue, and the microvascular perfusion were captured at 128 sites. Heartbeat-synchronized pulsations were found at all perfusion recordings. In 6 sites the perfusion was more than 6 times higher than the closest neighbor indicating a possible small vessel structure. TLI was significantly higher (p < 0.005) and the perfusion significantly lower (p < 0.005) in positions identified as white matter in the respective MRI batch. The measurements imply that LDPM has the potential to be used as an intracerebral guidance tool.

Place, publisher, year, edition, pages
S. Karger, 2007
Keywords
Deep brain stimulation, Laser Doppler perfusion monitoring, Microcirculation
National Category
Biomedical Laboratory Science/Technology
Identifiers
urn:nbn:se:liu:diva-48444 (URN)10.1159/000107360 (DOI)000249535300004 ()17709980 (PubMedID)2-s2.0-35348889232 (Scopus ID)
Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-12Bibliographically approved
Antonsson, J. (2007). On optical methods for intracerebral measurements during stereotactic and functional neurosurgery: Experimental studies. (Doctoral dissertation). : Institutionen för medicinsk teknik
Open this publication in new window or tab >>On optical methods for intracerebral measurements during stereotactic and functional neurosurgery: Experimental studies
2007 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Radio frequency (RF) lesioning and deep brain stimulation (DBS) are the two prevailing surgical treatments for movement disorders within the field of stereotactic and functional neurosurgery. For RF-lesioning, a small volume of brain tissue is coagulated and knowledge of the lesion size and growth is of great importance for the safety and outcome of the procedure. This thesis deals with adapting the laser Doppler perfusion monitoring (LDPM) technique for measurements in brain tissue during RF-lesioning. The relation between LDPM signal changes and developed lesion size was investigated. LDPM measurements were evaluated both in vitro (albumin protein solution) and in vivo in the porcine brain during RF-lesioning corresponding to a bilateral thalamotomy in man. The investigated signals from the LDPI measurements can be used for following the lesioning time course and to detect if a lesion was created, both in vitro and in the animal model. For the albumin model, both the total backscattered light intensity and the perfusion signal can be used as markers for estimating the final coagulation size, while in the animal model this conclusion was not statistical verified.

Independent on surgical method, RF-lesioning or DBS, intracerebral guidance is an important aspect within stereotactic and functional neurosurgery. To increase the accuracy and precision of reaching the correct target, different methods for intracerebral guidance exist, such as microelectrode recording and impedance methods. In this thesis, the possibility of developing an optical intracerebral guidance method has been investigated. Diffuse reflectance spectroscopy served as technology and all measurements were performed stereotactically in both porcine and human brain. Measurements of white and gray matter showed large differences, with higher reflectivity for white brain matter, both in porcine and in human brain. For the human measurements during DBS-implants, large differences between white matter and functional targets were found. Additionally, differences between native and lesioned porcine brain matter were detected. Both studies support the idea of using diffuse reflectance spectroscopy for developing an intracerebral guidance method.

Place, publisher, year, edition, pages
Institutionen för medicinsk teknik, 2007
Series
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1070
Keywords
Laser Doppler perfusion monitoring, Diffuse reflectance spectroscopy, Functional and stereotactic neurosurgery
National Category
Medical Laboratory and Measurements Technologies
Identifiers
urn:nbn:se:liu:diva-8081 (URN)978-91-85715-91-6 (ISBN)
Public defence
2007-02-02, Elsa Brändströms sal, Södra Entreén, Universitetssjukhuset, Linköping, 09:15 (English)
Opponent
Supervisors
Available from: 2007-01-26 Created: 2007-01-26 Last updated: 2016-05-04
Wårdell, K., Blomstedt, P., Antonsson, J., Eriksson, O., Richter, J. & Hariz, M. (2006). Intracerebral measurements during DBS-implatation using optical methods. In: Congress of the European Society for Stereotactic and Funktional Neurosurgery,2006: . New York: Springer
Open this publication in new window or tab >>Intracerebral measurements during DBS-implatation using optical methods
Show others...
2006 (English)In: Congress of the European Society for Stereotactic and Funktional Neurosurgery,2006, New York: Springer , 2006Conference paper, Published paper (Other academic)
Abstract [en]

   

Place, publisher, year, edition, pages
New York: Springer, 2006
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-35238 (URN)25847 (Local ID)25847 (Archive number)25847 (OAI)
Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-02-17Bibliographically approved
Antonsson, J., Eriksson, O., Lundberg, P. & Wårdell, K. (2006). Optical measurements during experimental stereotactic radiofrequency lesioning. Stereotactic and Functional Neurosurgery, 84(2-3), 118-124
Open this publication in new window or tab >>Optical measurements during experimental stereotactic radiofrequency lesioning
2006 (English)In: Stereotactic and Functional Neurosurgery, ISSN 1011-6125, E-ISSN 1423-0372, Vol. 84, no 2-3, p. 118-124Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to evaluate in vivo a laser Doppler measurement system in porcine brain tissue during thermal lesioning. A 2-mm monopolar radiofrequency lesioning electrode was equipped with optical fibers in order to monitor the lesioning procedure. Laser Doppler and backscattered light intensity signals were measured along the electrode trajectory and during bilateral lesioning in the central gray (70, 80 and 90°C, n = 14). The time course of the coagulation process could be followed by optical recordings. Two separate groups of tissue were identified from the intensity signals. The changes in the perfusion levels in both groups displayed significant changes (p < 0.05, n = 48) at all temperature settings, while backscattered light intensity was significant for only one group at the different temperatures (p < 0.05, n = 39). These results indicate that optical measurements correlate with lesion development in vivo. The study also indicates that it is possible to follow the lesioning process intra-operatively.

Place, publisher, year, edition, pages
S. Karger, 2006
Keywords
Laser Doppler, Radiofrequency lesioning, Functional neurosurgery, Brain electrodes
National Category
Biomedical Laboratory Science/Technology
Identifiers
urn:nbn:se:liu:diva-14233 (URN)10.1159/000094463 (DOI)000239562300010 ()16840822 (PubMedID)2-s2.0-33746647435 (Scopus ID)
Available from: 2007-01-26 Created: 2007-01-26 Last updated: 2017-12-13Bibliographically approved
Wårdell, K., Blomstedt, P., Antonsson, J., Eriksson, O., Richter, J., Zsigmond, P. & Hariz, M. (2006). Optiska mätningar under stereotaktisk neurokirurgi. In: Medicinteknikdagarna 2006,2006: .
Open this publication in new window or tab >>Optiska mätningar under stereotaktisk neurokirurgi
Show others...
2006 (Swedish)In: Medicinteknikdagarna 2006,2006, 2006Conference paper, Published paper (Other academic)
Abstract [sv]

  

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-36208 (URN)30547 (Local ID)30547 (Archive number)30547 (OAI)
Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-02-17Bibliographically approved
Yavari, N., Dam, J. S., Antonsson, J., Wårdell, K. & Anderson-Engels, S. (2005). In vitro measurements of optical properties of porcine brain using a novel compact device. Medical and Biological Engineering and Computing, 43(5), 658-666
Open this publication in new window or tab >>In vitro measurements of optical properties of porcine brain using a novel compact device
Show others...
2005 (English)In: Medical and Biological Engineering and Computing, ISSN 0140-0118, E-ISSN 1741-0444, Vol. 43, no 5, p. 658-666Article in journal (Refereed) Published
Abstract [en]

Knowledge of the optical properties of tissues can be applied in numerous medical and scientific fields, including cancer diagnostics and therapy. There are many different ways of determining the optical properties of turbid media. The paper describes measurements of the optical properties of porcine brain tissue using novel instrumentation for simultaneous absorption and scattering characterisation of small turbid samples. Integrating sphere measurements are widely used as a reference method for determination of the optical properties of relatively thin turbid samples. However, this technique is associated with bulky equipment, complicated measuring techniques, interference compensation techniques and inconvenient sample handling. It is believed that the sphere for some applications can be replaced by a new, compact device, called the combined angular and spatially resolved head sensor, to measure the optical properties of thin turbid samples. The results compare very well with data obtained with an integrating sphere for well-defined samples. The instrument was shown to be accurate to within 12% for μa and 1% for μ s in measurements of intralipid-ink samples. The corresponding variations of data were 17% and 2%, respectively. The reduced scattering coefficient for porcine white matter was measured to be 100 cm−1 at 633 nm, and the value for coagulated brain tissue was 65 cm−1. The corresponding absorption coefficients were 2 and 3 cm−1, respectively.

Place, publisher, year, edition, pages
Springer, 2005
Keywords
Optical properties, Turbid media, Integrating sphere, CASH sensor, Porcine brain tissue, Scattering
National Category
Other Medical Engineering
Identifiers
urn:nbn:se:liu:diva-14236 (URN)10.1007/BF02351040 (DOI)000234262300016 ()2-s2.0-29244462497 (Scopus ID)
Available from: 2007-01-26 Created: 2007-01-26 Last updated: 2017-12-13Bibliographically approved
Antonsson, J., Eriksson, O. & Wårdell, K. (2005). Radio frequency electrode system for optical lesion size estimation in functional neurosurgery. Journal of Biomedical Optics, 10(3), 1-6
Open this publication in new window or tab >>Radio frequency electrode system for optical lesion size estimation in functional neurosurgery
2005 (English)In: Journal of Biomedical Optics, ISSN 1083-3668, E-ISSN 1560-2281, Vol. 10, no 3, p. 1-6Article in journal (Refereed) Published
Abstract [en]

Radiofrequency(RF) lesioning in the human brain is one possible surgicaltherapy for severe pain as well as movement disorders. Oneobstacle for a safer lesioning procedure is the lack ofsize monitoring. The aim of this study was to investigateif changes in laser Doppler or intensity signals could beused as markers for size estimation during experimental RF lesioning.A 2 mm in diameter monopolar RF electrode was equippedwith optical fibers and connected to a digital laser Dopplersystem. The optical RF electrode's performance was equal to astandard RF electrode with the same dimensions. An albumin solutionwith scatterers was used to evaluate the intensity and laserDoppler signal changes during lesioning at 70, 80, and 90 °C.Significant signal changes were found for these three different clotsizes, represented by the temperatures (p<0.05,  n=10). The volume, width, andlength of the created coagulations were correlated to the intensitysignal changes (r=0.88, n=30, p<0.0001) and to the perfusion signalchanges (r=0.81, n=30, p<0.0001). Both static and Doppler-shifted light canbe used to follow the lesioning procedure as well asbeing used for lesion size estimation during experimental RF lesioning.

Place, publisher, year, edition, pages
SPIE - International Society for Optical Engineering, 2005
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:liu:diva-14232 (URN)10.1117/1.1924615 (DOI)000235127400040 ()16229664 (PubMedID)2-s2.0-24144476322 (Scopus ID)
Available from: 2007-01-26 Created: 2007-01-26 Last updated: 2017-12-13Bibliographically approved
Wårdell, K., Antonsson, J. & Eriksson, O. (2004). Optical markers for guidance during stereotactic neurosurgery. In: European Society for Stereotactic and Functional Neurosurgery ESSFN,2004: (pp. 881-881). Wien: Springer Verlag
Open this publication in new window or tab >>Optical markers for guidance during stereotactic neurosurgery
2004 (English)In: European Society for Stereotactic and Functional Neurosurgery ESSFN,2004, Wien: Springer Verlag , 2004, p. 881-881Conference paper, Published paper (Other academic)
Place, publisher, year, edition, pages
Wien: Springer Verlag, 2004
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-22183 (URN)1317 (Local ID)1317 (Archive number)1317 (OAI)
Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-02-22Bibliographically approved
Organisations

Search in DiVA

Show all publications