An interventional study of O-Arm Stereotactic imaging and Standard Stereotactic imaging in Parkinson Disease, sponsored by University Hospital, Toulouse. Completed at 1 site in France. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-05-07.
Sponsored by University Hospital, Toulouse · Not applicable, Interventional, and Diagnostic
During deep brain stimulation procedures in Parkinson's disease (PD), the most important prognostic element is the positioning of the surgical electrode in the subthalamic nucleus which is the anatomical target. The main objective of this project is therefore to compare 2 techniques thanks to a prospective comparative randomised open-label study: the use of O-ARM to acquire stereotactic imaging directly in the operating room and the standard technique requiring stereotactic imaging to be performed in the radiology department.
Prior to electrode implantation we perform stereotactic imaging which requires the fixation of a stereotactic frame on the patient's head before imaging (Magnetic Resonance Imaging MRI / Computed Tomography CT). Currently, it is necessary to transfer the patient to the imaging department outside of the operating room after the stereotactic frame has been placed, for imaging (either MRI or CT) and then to return to the operating room to begin the electrode implantation procedure. Since 2016, the new generation O-Arm 2 allows the acquisition of stereotactic imaging with the stereotactic frame in place by increasing the field of view (40 cm versus 20 cm previously) directly in the operating room. As a result, the transfer step to the MRI and CT scanner preoperatively may no longer be necessary, and the procedure can be started more quickly with greater comfort and safety for the patient and the anaesthesia team. Several teams around the world have begun to use framed O-Arm as the gold standard for stereotactic imaging. However, no randomised controlled study has been performed to date comparing O-Arm stereotactic imaging with pre-operative CT and/or MRI reference imaging.
4,487 studies on the registry are indexed under Parkinson Disease; 1,082 are open to participants now.
This study's enrollment of 24 is below the median of 40 across 3,294 interventional studies indexed under Parkinson Disease.
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Exclusion Criteria:
Imaging is performing directly in the operating room.
Procedure: O-Arm Stereotactic imaging
Imaging is performing in Radiology department.
Procedure: Standard Stereotactic imaging
Prior to electrode implantation, O-ARm stereotactic imaging (Magnetic Resonance Imaging)
Prior to electrode implantation, standard stereotactic imaging (Magnetic Resonance Imaging)
The absolute accuracy of Deep Brain Stimulation electrode implantation
The radial distance between the theoretical target and the electrode in the plane of the target regardless of the chosen trajectory (central, anterior, lateral). This distance corresponds to the minimum error between the target and the electrode. This measurement is made from the postoperative brain scan.
Time frame: 48 hours
The anatomical accuracy of Deep Brain Stimulation electrode implantation
Automatic calculation of the vector distance between the middle of pad 1 on the electrode and the theoretical target by software.
Time frame: 48 hours
Central and alternate position of the electrodes rate
Comparison of the anatomical location of the electrode compared to the anatomical target (subthalamic nucleus) after matching preoperative Magnetic Resonance Imaging (MRI) images
Time frame: 1 day
Surgical Times
Time from the end of the stereotactic frame to the surgical incision and time from the entry into room to the exit from room after generator implantation.
Time frame: 1 day
Clinical effectiveness
Comparison of The Unified Parkinson's Disease Rating Scale (UPDRS) II, III and IV scores between baseline and 6 months and then at 6 months between the 2 groups. The UPDRS scale is composed of 47 items grouped into three parts : II, III and IV. Responses scale ranging from 0 (normal/no symptoms) to 4 (severe).
Time frame: 6 months
Daily dose of Levodopa decrease
The change in Levodopa Equivalent Daily Dose (LEDD) before surgery and at 6 months compared between the 2 groups. This LEDD corresponds to the amount of antiparkinsonian treatments prescribed to the patient
Time frame: 6 months
Adverse effect rate
Clinical reporting of patient events/adverse reactions
Time frame: 6 months
Correlation between absolute accuracy and clinical effectiveness
Correlation between radial accuracy and UPDRS score for both groups
Time frame: 6 months
This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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University Hospital, Toulouse