Deep Brain Stimulation (DBS) is a well established surgical treatment for Parkinson’s Disease (PD) and Essential Tremor (ET). Electrical leads are surgically implanted in the deeply seated structures in the brain and chronically stimulated.
The location of the lead with respect to the anatomy is very important for optimal treatment.
Therefore, clinicians carefully plan the surgery, record electrophysiological signals from the region of interest and perform stimulation tests
to identify the best location to permanently place the leads.
Nevertheless, there are certain aspects of the surgery that can still be improved.
Firstly, therapeutic effects of stimulation are estimated by visually evaluating changes in tremor or passively moving patient’s limb to evaluate changes in rigidity. These methods are subjective and depend heavily on the experience of the evaluator.
Secondly, a significant amount of patient data is collected before and during the surgery like various CT and MR images, surgical planning information, electrophysiological recordings and results of stimulation tests. These are not fully utilized at the time of choosing the position for lead placement as they are either not available or acquired on separate systems or in the form of paper notes only.
Thirdly, studies have shown that the current target structures to implant the leads (Subthalamic Nucleus (STN) for PD and Ventral Intermediate Nucleus (VIM) for ET) may not be the only ones responsible for the therapeutic effects.
The objective of this doctoral work is to develop new methods that help clinicians subdue the above limitations which could in the long term improve the DBS therapy.
After a thorough review of the existing literature, specifically customized solutions were designed for the shortcomings described above. A new method to quantitatively evaluate tremor during DBS surgery using acceleration sensor was developed. The method was then adapted to measure acceleration of passive movements and to evaluate changes in rigidity through it.
Data from 30 DBS surgeries was collected by applying these methods in two clinical studies: one in Centre Hospitalier Universitaire (CHU),
Clermont-Ferrand and another multi-center study in Universit¨aspital Basel and Inselspital Bern in Switzerland.
To study the role of different anatomical structures in the therapeutic and adverse effects of stimulation, the data collected during the study was
analysed using two methods.
The first classical approach was to classify the data based on the anatomical structure in which the stimulating contact of the electrode was located.
The second advanced approach was to use patient-specific Finite Element Method (FEM) simulations of the Electric Field (EF) to estimate the spatial distribution of stimulation in the structures surrounding the electrode. Such simulations of the adverse effect inducing stimulation current amplitudes are used to visualize the boundaries of safe stimulation and identify structures that could be responsible for these effects. In addition, the patient-specific simulations are also used to develop a new method called ”Improvement Maps” to generate 2D and 3D visualization of intra operative stimulation test results with the patient images and surgical planning. This visualization summarized the stimulation test results by dividing the explored area into multiple regions based on the improvement in symptoms as measured by the accelerometric methods.
The accelerometric method successfully measured changes in tremor and rigidity.
Standard deviation, signal energy and spectral amplitude of dominant frequency correlated with changes in the symptoms.
Symptom suppressing stimulation current amplitudes identified through quantitative methods were lower than those identified through
the subjective methods.
Comparison of anatomical targets using the accelerometric data showed that to suppress rigidity in PD patients, stimulation current needed was
marginally higher for Fields of Forel (FF) and Zona Incerta (ZI) compared to STN.
On the other hand, the adverse effect occurrence rate was significantly lower in ZI and FF, indicating them to be better targets compared to STN.
Similarly, for ET patients, other thalamic nuclei like the Intermediolateral (InL) and Ventro-Oral (VO) as well as the Pre-Lemniscal Radiations (PLR) are as efficient in suppressing tremor as the VIM but have lower occurrence of adverse effects. Volumetric analysis of spatial distribution of stimulation agreed with these results suggesting that the structures other than the VIM could also play a role in therapeutic effects of stimulation. The visualization of the adverse effect simulations clearly show the structures which could be responsible for such effects e.g. stimulation in the internal capsula induced pyramidal effects.
These findings concur with the published literature. With regard to the improvement maps, the clinicians found them intuitive and easy to use to identify the optimal position for lead placement. If the maps were available during the surgery, the clinicians’ choice of lead placement would have been different.
This doctoral work has shown that modern techniques like quantitative symptom evaluation and
electric field simulations can suppress the existing drawbacks of the DBS surgery.
Furthermore, these methods along with 3D visualization of data can simplify tasks for clinicians of optimizing lead placement.
Better placement of the DBS lead can potentially reduce adverse effects and increase battery life of implanted pulse generator,
resulting in better therapy for patients.
Shah A.Lien vers l'article
Shah A. et al., Journal of Neurosurgery 2017, Coste J., Lemaire JJ., Schkommodau E., Taub E., Guzman R., Derost P., Hemm-Ode S. (2017) A novel assistive method for rigidity evaluation during deep brain stimulation surgery using acceleration sensors. Journal of Neurosurgery 127(3), 602-612
Shah A.Lien vers l'article
Shah A. et al., Medical & Biological Engineering & Computing 2017, Coste J., Lemaire JJ., Taub E., Schüpbach M., Pollo C., Schkommodau E., Guzman R., Hemm-Ode S. (2017) Intraoperative acceleration measurements to quantify improvement in tremor during deep brain stimulation surgery. Medical & Biological Engineering & Computing 55(5), 845-858
Hemm S.Lien vers l'article
Hemm S. et al., Frontiers in Human Neuroscience 2016, Pison D., Alonso F., Shah A., Coste J., Lemaire JJ., Wårdell K. (2016) Patient-specific electric field simulations and acceleration measurements for objective analysis of intraoperative stimulation tests in the thalamus. Frontiers in Human Neuroscience 10, 577
Vogel D., Shah A., Alonso F., Lemaire J.-J., Coste J., Wårdell K., Hemm S. (26-29 Septembre 2018) Co-registering Thalamus for Analysis of Patient-specific Intra-operative Improvement Maps in DBS (Communication affichée) - 23th Congress of the European Society for Stereotactic and Functional Neurosurgery (Edimbourg, Ecosse)
Actes publiés (résumé P094Lien vers le résumé
Stereotactic and Functional Neurosurgery
Facteur d'impact 2018: 1.905
) Stereotactic and Functional Neurosurgery 96 [Suppl. 1],
Shah A., Alonso F., Vogel D., Wardell K., Coste J., Lemaire J.-J., Pison D., Hemm S. (17-21 Juillet 2018) Analysis of adverse effects of stimulation during DBS surgery by patient-specific FEM simulations (Communication orale et affichée
Lien vers la communication) - 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (Honolulu, Hawaï)
Actes publiés (résumé ThuPoS14.15Lien vers le résumé
2018 40th Annual International Conference of the IEEE EMBC) 2018 40th Annual International Conference of the IEEE EMBC , 2222-2225
Shah A., Coste J., Lemaire JJ., Schkommodau E., Taub E., Guzman R., Derost P., Hemm-Ode S. (22 Septembre 2017) A novel assistive method for rigidity evaluation during deep brain stimulation surgery using acceleration sensors (Communication orale
Lien vers la communication) - 1ère journée conjointe TGI TechMed (Clermont-Ferrand)
Shah A., Alonso F., Lemaire J.-J., Pison D., Coste J., Wårdell K., Schkommodau E., Hemm S. (26-29 Juin 2017) Learning more about the optimal anatomical position for deep brain stimulation in essential tremor patients: 3d visualisation of intraoperative stimulation test results (Communication affichée) - 17th Quadrennial Meeting of the World Society for Stereotactic and Functional Neurosurgery (Berlin, Allemagne)
Actes publiés (résumé P013Lien vers le résumé
Stereotactic and Functional Neurosurgery
Facteur d'impact 2017: 1.648
) Stereotactic and Functional Neurosurgery 95[Suppl. 1], 186
Shah A., Alonso F., Lemaire J.-J., Pison D., Coste J., Wårdell K., Schkommodau E., Hemm S. (12-15 Juin 2017) 3D visualization of intraoperative stimulation test results in deep brain stimulation (Communication affichée
Lien vers la communication) - Joint conference of the European Medical and Biological Engineering Conference and the Nordic-Baltic Conference on Biomedical Engineering and Medical Physics (Tampere, Finlande)
Shah A., Alonso F., Pison D., Lemaire J.-J., Wårdell K., Coste J., Schkommodau E., Hemm-Ode S. (4-6 Octobre 2016) 3D Visualization of intraoperative stimulation test results for better target selection in DBS surgery (Communication affichée) - Meeting of the Swiss, Austrian and German Societies of Biomedical Engineering (Bâle, Suisse)
Actes publiés (résumé UPP04Lien vers le résumé
Biomedizinische Technik. Biomedical engineering
Facteur d'impact 2016: 0.915
) Biomedizinische Technik. Biomedical engineering 61[Suppl 1-U], S243
Shah A., Alonso F., Lemaire J.-J., Wårdell K., Pison D., Coste J., Schkommodau E., Hemm-Ode S. (28-30 Septembre 2016) Improving DBS targeting using 3D visualization of intraoperative stimulation tests (Communication affichée
Lien vers la communication) - 22th Congress of the European Society for Stereotactic and Functional Neurosurgery (Madrid, Espagne)
Actes publiés (résumé 8605Lien vers le résumé
Stereotactic and Functional Neurosurgery
Facteur d'impact 2016: 1.692
) Stereotactic and Functional Neurosurgery 94[Suppl. 1], 101
Shah A., Coste J., Lemaire J.-J., Taub E., Schüpbach M., Pollo C., Guzman R., Wårdell K., Schkommodau E., Hemm-Ode S. (28-30 Septembre 2016) Intraoperative quantitative tremor evaluation in deep brain stimulation surgery (Communication affichée) - 22th Congress of the European Society for Stereotactic and Functional Neurosurgery (Madrid, Espagne)
Actes publiés (résumé 8603Lien vers le résumé
Stereotactic and Functional Neurosurgery
Facteur d'impact 2016: 1.692
) Stereotactic and Functional Neurosurgery 94[Suppl. 1], 100-101
Shah A., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (16-18 Septembre 2015) Use of quantitative tremor evaluation to enhance target selection during deep brain stimulation surgery for essential tremor (Communication orale et affichée) - 49th annual conference of the German Society for Biomedical Engineering (Lübeck, Allemagne)
Actes publiés (résumé Lien vers le résumé
Current Directions in Biomedical Engineering
Facteur d'impact 2015:
) Current Directions in Biomedical Engineering 1[1], 488-492
Shah A., Coste J., Lemaire J.-J., Taub E., Guzman R., Schkommodau E., Hemm-Ode S. (10-11 Septembre 2015) Optimization of deep brain stimulation surgery for Parkinson’s disease with quantitative rigidity evaluation (Communication affichée
Lien vers la communication) - Joint annual meeting of the Swiss Societies of Neurosurgery and Neuroradiology (Lucerne, Suisse)
Actes publiés (résumé P054Lien vers le résumé
Journal of Neurological Surgery Part A: Central European Neurosurgery) Journal of Neurological Surgery Part A: Central European Neurosurgery 76[Suppl 01],
Pison D., Alonso F., Wårdell K., Shah A., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (7-12 Juin 2015) A method for side effect analysis based on electric field simulations for intraoperative test stimulation in deep brain stimulation surgery (Communication orale) - IUPESM World Congress on Medical Physics and Biomedical Engineering (Toronto, Canada)
Actes publiés (résumé SP121.2Lien vers le résumé
Abstracts IUPESM 2015 World Congress on Medical Physics & Biomedical Eng...) Abstracts IUPESM 2015 World Congress on Medical Physics & Biomedical Eng... , 348
Pison D., Alonso F., Wårdell K., Shah A., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (22-24 Avril 2015) A method for electric field simulations and acceleration measurements for intraoperative test stimulation (Communication affichée
Lien vers la communication) - 7th international IEEE EMBS Conference on Neural Engineering (Montpellier)
Actes publiés (résumé 485Lien vers le résumé
Neural Engineering (NER), 2015 7th International IEEE/EMBS Conference on) Neural Engineering (NER), 2015 7th International IEEE/EMBS Conference on ,
Shah A., Coste J., Lemaire J.-J., Schkommodau E., Guzman R., Taub E., Hemm-Ode S. (22-24 Avril 2015) Using acceleration sensors to identify rigidity release threshold during Deep Brain Stimulation surgery (Communication affichée
Lien vers la communication) - 7th international IEEE EMBS Conference on Neural Engineering (Montpellier)
Actes publiés (résumé 520Lien vers le résumé
Neural Engineering (NER), 2015 7th International IEEE/EMBS Conference on) Neural Engineering (NER), 2015 7th International IEEE/EMBS Conference on ,
Hemm-Ode S., Pison D., Alonso F., Shah A., Coste J., Lemaire J.-J., Schkommodau E., Wårdell K. (17-20 Septembre 2014) A method for electric field simulations and acceleration measure-ments for intraoperative test stimulation (Communication affichée
Lien vers la communication) - 21th Congress of the European Society for Stereotactic and Functional Neurosurgery (Maastricht, Pays-Bas)
Actes publiés (résumé 91Lien vers le résumé
Stereotactic and Functional Neurosurgery
Facteur d'impact 2014: 2.019
) Stereotactic and Functional Neurosurgery 92[Suppl 2], 153
Shah A., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (17-20 Septembre 2014) Correlation analysis between quantitatively analyzed stimulation effects and anatomical position during deep brain stimulation surgery (Communication affichée
Lien vers la communication) - 21th Congress of the European Society for Stereotactic and Functional Neurosurgery (Maastricht, Pays-Bas)
Actes publiés (résumé 145Lien vers le résumé
Stereotactic and Functional Neurosurgery
Facteur d'impact 2014: 2.019
) Stereotactic and Functional Neurosurgery 92[Suppl 2], 167
Shah A., Kaewmulpet C., Pontier B., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (27-28 Aout 2014) Quantitative evaluation of muscle tone using force and acceleration sensors (Communication affichée
Lien vers la communication) - Swiss Society for Biomedical Engineering 2014 Annual Meeting (Zurich, Suisse)
Shah A., Coste J., Lemaire J.-J., Ulla M., Schkommodau E., Hemm-Ode S. (8-12 Juin 2014) Acceleration measurements to quantify changes in rigidity during deep brain stimulation surgery (Communication affichée
Lien vers la communication) - 18th International Congress of Parkinson's Disease and Movement Disorders (Stockholm, Suède)
Actes publiés (résumé 83Lien vers le résumé
Movement Disorders
Facteur d'impact 2014: 5.680
) Movement Disorders 29[Suppl. 1], S30-S31
Hemm-Ode S., Alonso F., Pison D., Shah A., Coste J., Lemaire J.-J., Wårdell K. (15-16 Mai 2014) Patient-specific electric field simulations and acceleration measurements for intraoperative test-stimulations (Communication orale) - 1st IMPACT Workshop and 7th NeuroTech Workshop (Linköping, Suède)
Shah A., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (8-11 Décembre 2013) Quantifying changes in patient tremor using accelerometer during deep brain stimulation surgery (Communication affichée) - 20th World Congress on Parkinson's Disease and Related Disorders (Genève, Suisse)
Shah A., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (6-8 Novembre 2013) A method to quantitatively evaluate changes in tremor during Deep Brain Stimulation surgery (Communication orale
Lien vers la communication) - 6th international IEEE EMBS Conference on Neural Engineering (San Diego, Etats-Unis)
Actes publiés (résumé 14001804Lien vers le résumé
Neural Engineering (NER), 2013 6th International IEEE/EMBS Conference on) Neural Engineering (NER), 2013 6th International IEEE/EMBS Conference on , 1202-1205
Hemm-Ode S., Wettmann P., Kistler B., Behm P., Schkommodau E., Coste J., Lemaire J.-J., Shah A. (19-21 Septembre 2013) Intraoperative optical flow based tremor evaluation - a feasibility study (Communication affichée) - 47th annual conference of the German Society for Biomedical Engineering (Graz, Autriche)
Actes publiés (résumé S1-A-4008Lien vers le résumé
Biomedizinische Technik. Biomedical engineering
Facteur d'impact 2013: 0.731
) Biomedizinische Technik. Biomedical engineering 58[Suppl 1-A], 4008
Shah A., Coste J., Schkommodau E., Hemm-Ode S., Lemaire J.-J. (19-21 Septembre 2013) Using acceleration to quantify symptoms during deep brain stimulation surgery (Communication affichée) - 47th annual conference of the German Society for Biomedical Engineering (Graz, Autriche)
Actes publiés (résumé S1-A-4007Lien vers le résumé
Biomedizinische Technik. Biomedical engineering
Facteur d'impact 2013: 0.731
) Biomedizinische Technik. Biomedical engineering 58[Suppl 1-A], 4007
Shah A., Coste J., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (26-29 Juin 2013) A method to quantitatively evaluate tremor during deep brain stimulation surgery (Communication orale) - 27th International Congress and Exhibition, Computer Assisted Radiology and Surgery Associated Societies (Heidelberg, Allemagne)
Actes publiés (résumé Lien vers le résumé
International Journal of Computer Assisted Radiology and Surgery
Facteur d'impact 2013: 1.659
) International Journal of Computer Assisted Radiology and Surgery 8[Suppl 1], S213-S214
Shah A., Coste J., Ulla M., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (28-29 Septembre 2012) Acceleration measurements during DBS surgery for tremor (Communication affichée) - 1st International Symposium on Deep Brain Connectomics (Clermont-Ferrand)
Shah A., Coste J., Gmünder D., Ulla M., Lemaire J.-J., Schkommodau E., Hemm-Ode S. (26-29 Septembre 2012) Quantitative rigidity and tremor evaluation using accelerometer during deep brain stimulation surgery - a preliminary study (Communication affichée) - 20th Congress of the European Society for Stereotactic and Functional Neurosurgery (Lisbonne, Portugal)
Actes publiés (résumé MOVDIS/P/95Lien vers le résumé
Stereotactic and Functional Neurosurgery
Facteur d'impact 2012: 1.458
) Stereotactic and Functional Neurosurgery 90[S1], 138
Hemm-Ode S., Gmünder D., Shah A., Ulla M., Lemaire J.-J., Coste J. (17-19 Septembre 2012) Quantitative rigidity evaluation during deep brain stimulation surgery - a preliminary study (Communication affichée) - 46th annual conference of the German Society for Biomedical Engineering (Iéna, Allemagne)
Actes publiés (résumé S1-H-698Lien vers le résumé
Biomedizinische Technik. Biomedical engineering
Facteur d'impact 2012: 1.157
) Biomedizinische Technik. Biomedical engineering 57[Suppl 1-H], 698
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