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Background and purpose: The aim of the study is to predict the subthalamic nucleus (STN) deep brain stimulation (DBS) outcomes for Parkinson's disease (PD) patients using the radiomic features extracted from pre-operative magnetic resonance images (MRI). Methods: The study included 34 PD patients who underwent DBS implantation in the STN. Five patients (15%) showed poor DBS motor outcome. All together 9 amygdalar nuclei and 12 hippocampus subfields were segmented using Freesurfer 7.0 pipeline from pre-operative MRI images. Furthermore, PyRadiomics platform was used to extract 120 radiomic features for each nuclei and subfield resulting in 5,040 features. Minimum Redundancy Maximum Relevance (mRMR) feature selection method was employed to reduce the number of features to 20, and 8 machine learning methods (regularized binary logistic regression (LR), decision tree classifier (DT), linear discriminant analysis (LDA), naive Bayes classifier (NB), kernel support vector machine (SVM), deep feed-forward neural network (DNN), one-class support vector machine (OC-SVM), feed-forward neural network-based autoencoder for anomaly detection (DNN-A)) were applied to build the models for poor vs. good and very good STN-DBS motor outcome prediction. Results: The highest mean prediction accuracy was obtained using regularized LR (96.65 ± 7.24%, AUC 0.98 ± 0.06) and DNN (87.25 ± 14.80%, AUC 0.87 ± 0.18). Conclusion: The results show the potential power of the radiomic features extracted from hippocampus and amygdala MRI in the prediction of STN-DBS motor outcomes for PD patients. [ABSTRACT FROM AUTHOR]

Introduction. Deep brain stimulation (DBS) of subthalamic nucleus (STN) is widely accepted treatment of Parkinson's disease (PD) patients. It has been reported that PD patients undergoing STNDBS procedure are at elevated risk to experience wide range of mental disorders that include delirium and other psychotic disorders, mood disorders, anxiety disorders and neurocognitive disorders. Here we present a case of PD patient who developed psychiatric complications following bilateral STN-DBS implantation. Case report. A 72-year old male patient with a 12-year history of PD was referred for bilateral STN-DBS implantation procedure. The patient had no past history of mental disorders and was physically healthy based on standard clinical and laboratory investigations. On preoperative Magnetic Resonance Imaging neither the STN nor red nucleus were reliably visible. Therefore, it was decided to implant bilateral STN leads according to anterior commissure -- posterior commissure indirect targeting method and with intraoperative microstimulation and macro-stimulation of STN. The procedure was uneventful. However, next day after the procedure the patient developed typical delirium symptoms, which resolved during the next few days. However, a few weeks after the procedure the patient developed acute psychosis with visual hallucinations, delusions of persecution and reference, severe anxiety symptoms, psychomotoric agitation and disorganized speech. After one month inpatient treatment of psychosis, the patient developed depressive disorder with symptoms of apathy and cognitive decline. The patient was discharged home on psychiatric treatment that included antipsychotic and antidepressant medication and his DBS stimulation was switched to monopolar bilateral stimulation. During treatment his psychosis symptoms remitted but the patients developed moderate severity depressive symptoms, which started to regress after switching to bipolar STN stimulation. [ABSTRACT FROM AUTHOR]

Most severe complications of DBS appear in the perioperative period. There are no published case reports of delayed ICH occurring more than three months from electrode implantation. The pathogenesis of delayed ICH remains unclear. We present a 64-year-old male with essential tremor who sustained a delayed intracerebral hemorrhage (ICH) 2.5 years after implantation of a deep brain stimulating electrode. The patient sustained a thalamic-midbrain ICH that may have been related to the positioning of the electrode. An analysis was performed to determine the cause and risk factors that may have contributed. Based on these findings, it is possible that the proximity of the cannula or electrode may have mildly injured the wall of the superior thalamic vein during implantation, or perhaps being in contact with the vein over a longer-term having an effect, which in either of these scenarios can subsequently lead to ICH formation on the sudden rise of intracranial pressure. It emphasizes the importance of proper surgical navigation planning, image- guidance, and the use of image verification. • No reports of delayed ICH occurring more than 3 months from DBS electrode implantation • A delayed intracerebral hemorrhage 2.5 years after implantation of a DBS electrode is reported • Possible that the cannula or electrode may have injured the wall of superior thalamic vein during implantation • DBS candidates should be instructed about delayed ICH risk [ABSTRACT FROM AUTHOR]

Brain MRI voxel based morphometry (VBM) is known as a research tool for neurodegenerative and psychiatric disorders. The aim of this study was to evaluate a possible association of cortical thickness, cortical and subcortical volume in PD pa-tients.with neuropsychiatric disturbancies after deep brain stimulation, sleep impairment and quality of life. Methods. Twenty-eight PD patients (14 men and 14 women, median age 58 years) were evaluated for sleep disturbances with PDSS, quality of life with PDQ-39, SF-36 and underwent brain MRI. Twenty-two of these patients underwent STN-DBS and observed for neuropsychiatric complications after STN-DBS implantation surgery. Control group consisted of 28 healthy volunteers who were matched by age and gender. Automated voxel based image analysis was performed with the FreeSurfer software. Results. PD patients with nocturnal hallucinations had prominent basal ganglia volume reduction. Distressful dreams were associated with limbic system and frontal white matter changes. Volumetric analysis showed significant differences in cortical thickness between STN-DBS patients with and without postoperative neuropsychiatric complications in 13 gyruses on the right hemisphere and in 7 gyruses on the left hemisphere. White matter volume analysis showed also its reduction in the left caudal middle frontal area. Foundings suggest that neuropsychiatric complications after DBS can be associated with excitation of frontal-striatum-thalamus and temporal-parietal circuits. Decreased social functioning in PD patients can be associated with white matter reduction in cingulate area. Conclusions. Neuropsychiatric complications after DBS can be associated with excitation offrontal-striatum-thalamusand temporal-parietal circuits. PD patients with nocturnal hallucinations had prominent basal ganglia volume reduction [ABSTRACT FROM AUTHOR]