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Johansson, Johannes D
Alternative names
Publications (10 of 41) Show all publications
Johansson, J., Portaluppi, D., Buttafava, M. & Villa, F. (2018). Development of a hybrid laser Doppler flowmetry and diffuse correlation spectroscopy system. In: : . Paper presented at Medicinteknikdagarna, Umeå, 9-10 oktober 2018.
Open this publication in new window or tab >>Development of a hybrid laser Doppler flowmetry and diffuse correlation spectroscopy system
2018 (English)Conference paper, Oral presentation with published abstract (Refereed)
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-152444 (URN)
Conference
Medicinteknikdagarna, Umeå, 9-10 oktober 2018
Available from: 2018-10-31 Created: 2018-10-31 Last updated: 2018-10-31
Rejmstad, P., Johansson, J. D., Haj-Hosseini, N. & Wårdell, K. (2017). A method for monitoring of oxygen saturation changes in brain tissue using diffuse reflectance spectroscopy. Journal of Biophotonics, 10(3), 446-455
Open this publication in new window or tab >>A method for monitoring of oxygen saturation changes in brain tissue using diffuse reflectance spectroscopy
2017 (English)In: Journal of Biophotonics, ISSN 1864-063X, E-ISSN 1864-0648, Vol. 10, no 3, p. 446-455Article in journal (Refereed) Published
Abstract [en]

Continuous measurement of local brain oxygen saturation (SO2) can be used to monitor the status of brain trauma patients in the neurocritical care unit. Currently, micro-oxygen-electrodes are considered as the “gold standard” in measuring cerebral oxygen pressure (pO2), which is closely related to SO2 through the oxygen dissociation curve (ODC) of hemoglobin, but with the drawback of slow in response time. The present study suggests estimation of SO2 in brain tissue using diffuse reflectance spectroscopy (DRS) for finding an analytical relation between measured spectra and the SO2 for different blood concentrations. The P3 diffusion approximation is used to generate a set of spectra simulating brain tissue for various levels of blood concentrations in order to estimate SO2. The algorithm is evaluated on optical phantoms mimicking white brain matter (blood volume of 0.5–2%) where pO2 and temperature is controlled and on clinical data collected during brain surgery. The suggested method is capable of estimating the blood fraction and oxygen saturation changes from the spectroscopic signal and the hemoglobin absorption profile.

Place, publisher, year, edition, pages
Wiley-VCH Verlagsgesellschaft, 2017
Keywords
oxygenation, diffuse reflectance spectroscopy, hemoglobin, optical phantom, human brain
National Category
Other Medical Engineering
Identifiers
urn:nbn:se:liu:diva-127362 (URN)10.1002/jbio.201500334 (DOI)000398216200012 ()27094015 (PubMedID)
Note

Funding agencies: Swedish Childhood Cancer Foundation; Swedish Research Council [621-2010-4216, 621-2013-6078]

Available from: 2016-04-22 Created: 2016-04-22 Last updated: 2017-04-20Bibliographically approved
Wårdell, K., Johansson, J. & Alonso, F. (2017). Deep brain stimulation: software for patient-specific electric field simulations. In: : . Paper presented at World Society for Stereotactic and Functional Neurosurgery, 17th Quadrennial meeting, Berlin June 26-29, 2017.
Open this publication in new window or tab >>Deep brain stimulation: software for patient-specific electric field simulations
2017 (English)Conference paper, Poster (with or without abstract) (Refereed)
Abstract [en]

Introduction

The electric field (EF) around the active deep brain stimulation (DBS) contact is of interest for optimizing the therapeutic effect. We have previously developed a method for simulation and visualization of the EF. The aim of the project is to improve the software for quick and user friendly simulations.  

Methods

The ELMA software for brain model creation has been improved by adding quick ROI selection and transformation to an electrical conductivity map based on tissue classification through multiple slices of the preoperative MRI. These data are used as input for Comsol Multiphysics simulations of the EF. Two points along the position of the lead, as seen in the postoperative images, are used for correct placement in the brain model. Multiple DBS lead models are pre-programmed. The active contact and amplitude are user-selected.

Results

After a simulation the result is visualized with a user defined isolevel or isosurface superimposed on the patients preoperative MRI. An example is shown in Fig. 1. The 3389 lead is places in zona inserta (Zi) and contact 1 activated with 2 and 4 V respectively. An isolevel of 0.2 V/mm is used corresponding to a ~ 3-4 µm axon diameter when using a pulse length of 60 µs. More examples will be presented at the meeting.

Conclusion

The software for patient-specific simulations of EF around DBS electrodes has been improved for quicker simulations and more DBS leads. As a next step user friendly Apps will be implemented.

National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-139879 (URN)
Conference
World Society for Stereotactic and Functional Neurosurgery, 17th Quadrennial meeting, Berlin June 26-29, 2017
Available from: 2017-08-21 Created: 2017-08-21 Last updated: 2017-08-21
Johansson, J., Akbarian-Tefaghi, L., Harith, A., Zrinzo, L., Limousin, P., Joyce, E., . . . Foltynie, T. (2017). Estimation of effective target area in the globus pallidus during deep brain stimulation for Tourette syndrome.. In: : . Paper presented at World Society for Stereotactic and Functional Neurosurgery, 17th Quadrennial meeting, Berlin June 26-29, 2017.
Open this publication in new window or tab >>Estimation of effective target area in the globus pallidus during deep brain stimulation for Tourette syndrome.
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2017 (English)Conference paper, Oral presentation only (Refereed)
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-139858 (URN)
Conference
World Society for Stereotactic and Functional Neurosurgery, 17th Quadrennial meeting, Berlin June 26-29, 2017
Available from: 2017-08-17 Created: 2017-08-17 Last updated: 2017-08-17
Göransson, N., Johansson, J., Alonso, F., Wårdell, K. & Zsigmond, P. (2017). Postoperative lead movement after deep brain stimulation surgery and changes of stimulation area. In: : . Paper presented at World Society for Stereotactic and Functional Neurosurgery, 17th Quadrennial meeting, Berlin June 26-29, 2017. S. Karger
Open this publication in new window or tab >>Postoperative lead movement after deep brain stimulation surgery and changes of stimulation area
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2017 (English)Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

Introduction

Lead movement after deep brain stimulation (DBS) may occur and influence the area of stimulation. The cause of the displacement is not fully understood. The aim of the study was to investigate differences in lead position between the day after surgery and approximately one month postoperatively and also simulate the electric field (EF) around the active contacts.

Methods

23 patients with movement disorders underwent DBS surgery (37 leads). CT at the two time points were co-fused respectively with the stereotactic images in Surgiplan. The coordinates (x, y, z) of the lead tips were compared between the two dates (paired t-test). 8 of these patients were selected for the EF simulation in Comsol Multiphysics.

Results

There was a significant discrepancy (mean ± s.d.) on the left lead: x (0.44 ± 0.72, p < 0.01), y (0.64 ± 0.54, p < 0.001), z (0.62 ± 0.71, p < 0.001).  On the right lead, corresponding values were: x (-0.11 ± 0.61, n.s.), y (0.71 ± 0.54, p < 0.001), z (0.49 ± 0.81, p < 0.05).  No correlation was found between bilateral (n =14) vs. unilateral DBS, gender (n = 17 male) and age < 60 years (n = 8).  The lead movement affected the EF spread (Fig. 1).

Conclusion

The left lead tip displayed a tendency to move lateral, anterior and inferior and the right a tendency to move anterior and inferior. Lead movement after DBS can be a factor to consider before starting the stimulation. The differences in the area of stimulation might affect clinical outcome.

Place, publisher, year, edition, pages
S. Karger, 2017
Series
Stereotactic and Functional Neurosurgery, ISSN 1011-6125, E-ISSN 1423-0372
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-139886 (URN)10.1159/000478281 (DOI)
Conference
World Society for Stereotactic and Functional Neurosurgery, 17th Quadrennial meeting, Berlin June 26-29, 2017
Available from: 2017-08-21 Created: 2017-08-21 Last updated: 2017-09-04
Akbarian-Tefaghi, L., Akram, H., Johansson, J., Zrinzo, L., Kefalopoulou, Z., Limousin, P., . . . Foltynie, T. (2017). Refining the Deep Brain Stimulation Target within the Limbic Globus Pallidus Internus for Tourette Syndrome. Stereotactic and Functional Neurosurgery, 95(4), 251-258
Open this publication in new window or tab >>Refining the Deep Brain Stimulation Target within the Limbic Globus Pallidus Internus for Tourette Syndrome
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2017 (English)In: Stereotactic and Functional Neurosurgery, ISSN 1011-6125, E-ISSN 1423-0372, Vol. 95, no 4, p. 251-258Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: Deep brain stimulation (DBS) in patients with severe, refractory Tourette syndrome (TS) has demonstrated promising but variable results thus far. The thalamus and anteromedial globus pallidus internus (amGPi) have been the most commonly stimulated sites within the cortico-striato thalamic circuit, but an optimal target is yet to be elucidated.

OBJECTIVES: This study of 15 patients with long-term amGPi DBS for severe TS investigated whether a specific anatomical site within the amGPi correlated with optimal clinical outcome for the measures of tics, obsessive compulsive behaviour (OCB), and mood.

METHODS: Validated clinical assessments were used to measure tics, OCB, quality of life, anxiety, and depression before DBS and at the latest follow-up (17-82 months). Electric field simulations were created for each patient using information on electrode location and individual stimulation parameters. A subsequent regression analysis correlated these patient-specific simulations to percentage changes in outcome measures in order to identify any significant voxels related to clinical improvement.

RESULTS: A region within the ventral limbic GPi, specifically on the medial medullary lamina in the pallidum at the level of the AC-PC, was significantly associated with improved tics but not mood or OCB outcome.

CONCLUSIONS: This study adds further support to the application of DBS in a tic-related network, though factors such as patient sample size and clinical heterogeneity remain as limitations and replication is required.

Place, publisher, year, edition, pages
S. Karger, 2017
Keywords
Deep brain stimulation, Globus pallidus internus, Modelling, Simulation, Tourette syndrome
National Category
Medical Engineering
Identifiers
urn:nbn:se:liu:diva-139857 (URN)10.1159/000478273 (DOI)000410846200006 ()28787721 (PubMedID)2-s2.0-85027141067 (Scopus ID)
Note

Funding agencies: National Institute of Health Research (NIHR) Biomedical Research Centre at the UCL Institute of Neurology and UCLH-National Hospital for Neurology and Neurosurgery, London, UK; Swedish Research Council (Vetenskapsradet) [2016-03564]; Swedish Foundation fo

Available from: 2017-08-17 Created: 2017-08-17 Last updated: 2017-10-05Bibliographically approved
Mireles, M., Johansson, J. D., Farzam, P., Martínez Lozano, M., Casanovas, O., Durduran, T. & Morales, J. (2016). A non-contact, small animal scanner based on diffuse optical spectroscopy and diffuse correlation spectroscopy. In: : . Paper presented at Optical Tomography and Spectroscopy 2016, Fort Lauderdale, Florida United States, 25–28 April 2016.
Open this publication in new window or tab >>A non-contact, small animal scanner based on diffuse optical spectroscopy and diffuse correlation spectroscopy
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2016 (English)Conference paper, Published paper (Refereed)
Abstract [en]

A scanning system that combines broadband diffuse optical spectroscopy and diffuse correlation spectroscopy for non-contact, large field-of-view imaging of small animal models and humans is presented and demonstrated in vivo.

National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:liu:diva-129013 (URN)10.1364/OTS.2016.OTh1D.4 (DOI)978-1-943580-10-1 (ISBN)
Conference
Optical Tomography and Spectroscopy 2016, Fort Lauderdale, Florida United States, 25–28 April 2016
Available from: 2016-06-08 Created: 2016-06-08 Last updated: 2016-06-27
Lindner, C., Mora, M., Farzam, P., Squarcia, M., Johansson, J., Weigel, U. M., . . . Durduran, T. (2016). Diffuse Optical Characterization of the Healthy Human Thyroid Tissue and Two Pathological Case Studies.. PLoS ONE, 11(1)
Open this publication in new window or tab >>Diffuse Optical Characterization of the Healthy Human Thyroid Tissue and Two Pathological Case Studies.
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2016 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 1Article in journal (Refereed) Published
Abstract [en]

The in vivo optical and hemodynamic properties of the healthy (n = 22) and pathological (n = 2) human thyroid tissue were measured non-invasively using a custom time-resolved spectroscopy (TRS) and diffuse correlation spectroscopy (DCS) system. Medical ultrasound was used to guide the placement of the hand-held hybrid optical probe. TRS measured the absorption and reduced scattering coefficients (μa, μs') at three wavelengths (690, 785 and 830 nm) to derive total hemoglobin concentration (THC) and oxygen saturation (StO2). DCS measured the microvascular blood flow index (BFI). Their dependencies on physiological and clinical parameters and positions along the thyroid were investigated and compared to the surrounding sternocleidomastoid muscle. The THC in the thyroid ranged from 131.9 μM to 144.8 μM, showing a 25-44% increase compared to the surrounding sternocleidomastoid muscle tissue. The blood flow was significantly higher in the thyroid (BFIthyroid = 16.0 × 10-9 cm2/s) compared to the muscle (BFImuscle = 7.8 × 10-9 cm2/s), while StO2 showed a small (StO2, muscle = 63.8% to StO2, thyroid = 68.4%), yet significant difference. Two case studies with thyroid nodules underwent the same measurement protocol prior to thyroidectomy. Their THC and BFI reached values around 226.5 μM and 62.8 × 10-9 cm2/s respectively showing a clear contrast to the nodule-free thyroid tissue as well as the general population. The initial characterization of the healthy and pathologic human thyroid tissue lays the ground work for the future investigation on the use of diffuse optics in thyroid cancer screening.

National Category
Cancer and Oncology
Identifiers
urn:nbn:se:liu:diva-125651 (URN)10.1371/journal.pone.0147851 (DOI)26815533 (PubMedID)
Available from: 2016-02-29 Created: 2016-02-29 Last updated: 2017-11-30
Lindner, C., Mora Porta, M., Farzam, P., Squarcia, M., Johansson, J. D., Weigel, U., . . . Durduran, T. (2016). Diffuse optical characterization of the human thyroid. In: : . Paper presented at Cancer Imaging and Therapy 2016 Fort Lauderdale, Florida United States, 25–28 April 2016.
Open this publication in new window or tab >>Diffuse optical characterization of the human thyroid
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2016 (English)Conference paper, Published paper (Refereed)
Abstract [en]

The human thyroid was measured by ultrasound-guided near-infrared time-resolved spectroscopy and diffuse correlation spectroscopy characterizing the healthy thyroid and nodules allowing us to envision applications in thyroid cancer screening.

National Category
Medical Laboratory and Measurements Technologies
Identifiers
urn:nbn:se:liu:diva-129010 (URN)10.1364/CANCER.2016.CTh4A.5 (DOI)978-1-943580-10-1 (ISBN)
Conference
Cancer Imaging and Therapy 2016 Fort Lauderdale, Florida United States, 25–28 April 2016
Available from: 2016-06-08 Created: 2016-06-08 Last updated: 2016-06-27
Johansson, J. D., Mireles, M., Morales-Dalmau, J., Farzam, P., Martínez-Lozano, M., Casanovas, O. & Durduran, T. (2016). Scanning, non-contact, hybrid broadband diffuse optical spectroscopy and diffuse correlation spectroscopy system.. Biomedical Optics Express, 7(2), 481-498
Open this publication in new window or tab >>Scanning, non-contact, hybrid broadband diffuse optical spectroscopy and diffuse correlation spectroscopy system.
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2016 (English)In: Biomedical Optics Express, ISSN 2156-7085, E-ISSN 2156-7085, Vol. 7, no 2, p. 481-498Article in journal (Refereed) Published
Abstract [en]

A scanning system for small animal imaging using non-contact, hybrid broadband diffuse optical spectroscopy (ncDOS) and diffuse correlation spectroscopy (ncDCS) is presented. The ncDOS uses a two-dimensional spectrophotometer retrieving broadband (610-900 nm) spectral information from up to fifty-seven source-detector distances between 2 and 5 mm. The ncDCS data is simultaneously acquired from four source-detector pairs. The sample is scanned in two dimensions while tracking variations in height. The system has been validated with liquid phantoms, demonstrated in vivo on a human fingertip during an arm cuff occlusion and on a group of mice with xenoimplanted renal cell carcinoma.

National Category
Biochemistry and Molecular Biology
Identifiers
urn:nbn:se:liu:diva-128781 (URN)10.1364/BOE.7.000481 (DOI)26977357 (PubMedID)
Available from: 2016-05-30 Created: 2016-05-30 Last updated: 2017-11-30
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