Anatomo-clinical atlases correlate clinical data and electrode contact coordinates: Application to subthalamic deep brain stimulation

Abstract

For patients suffering from Parkinson's disease with severe movement disorders, functional surgery may be required when medical therapy is not effective. In Deep Brain Stimulation (DBS), electrodes are implanted within the brain to stimulate deep structures such as SubThalamic Nucleus (STN). The quality of patient surgical outcome is generally related to the accuracy of nucleus targeting during surgery. In this paper, we focused on identifying optimum sites for STN DBS by studying symptomatic motor improvement along with neuropsychological side effects. We described successive steps for constructing digital atlases gathering patient's location of electrode contacts automatically segmented from postoperative images, and clinical scores. Three motor and five neuropsychological scores were included in the study. Correlations with active contact locations were carried out using an adapted hierarchical ascendant classification. Such analysis enabled the extraction of representative clusters to determine the optimum site for therapeutic STN DBS. For each clinical score, we built an anatomo-clinical atlas representing its improvement or deterioration in relation with the anatomical location of electrodes and from a population of implanted patients. To the best of our knowledge, we reported for the first time a discrepancy between a very good motor improvement by targeting the postero-superior region of the STN and an inevitable deterioration of the categorical and phonemic fluency in the same region. Such atlases and associated analysis may help better understanding of functional mapping in deep structures and may help pre-operative decision-making process and especially targeting.

Texture feature evaluation for segmentation of historical document images

“…clusters are grouped when the intra-cluster inertia is minimal. This linkage between clusters was performed by using the Ward criterion [43] along with the weighted Euclidean distance [20]. In the perspective of historical collection valorization and in the context of an unsupervised clustering, the authors of [29] present interesting classification results obtained by performing HAC on stroke features of initial letters.…”

Data-Driven Prediction of the Therapeutic Window during Subthalamic Deep Brain Stimulation Surgery

“…Therefore, functional atlases have been developed to predict the DBS outcome. These atlases could be coordinate-based [20,21], enhanced with biophysical models [22], or more recently can adopt a connectomic approach [23,24]. Main limitations are the discrepancies between the methods used that prevent the transfer between medical centers and the lack of prospective validation.…”

Patient-Specific Electric Field Simulations and Acceleration Measurements for Objective Analysis of Intraoperative Stimulation Tests in the Thalamus

“…The use of the patient-specific MR-WAIR sequence together with a 4.7 T in-house atlas as reference and stereotactic books make an approximate identification of the structures possible (Zerroug et al, 2016). Other groups have proposed various approaches (Caire et al, 2013) among them projecting the position of the active contact(s) directly onto anatomical images (Vayssiere et al, 2004), onto anatomical (Saint-Cyr et al, 2002; Sarnthein et al, 2013) or probabilistic functional atlases (Lalys et al, 2013), or linking them to MER results (Zonenshayn et al, 2004) sometimes combined with imaging data (Weise et al, 2013) and white matter tracking (Coenen et al, 2012). To analyze the relationship between the anatomical location of stimulating contacts and the clinical effectiveness of stimulation, we have decided to take into account the extent of stimulation by using EF simulations (Åström et al, 2012) as discussed in detail in the next paragraph.…”