INTRODUCTION
Implantation of deep brain stimulation of the subthalamic nucleus is a recognized treatment for medically intractable Parkinson’s disease. There are several procedures which mainly differ by type of anesthesia, use of microelectrode recording, postoperative images acquisition, etc. This work presents a procedure of DBS lead implantation under general anesthesia with targeting of the subthalamic nucleus based on preoperative MRI fused with stereotactic preoperative CT and verification of lead position based on fused preoperative MRI with postoperative 3D Zeego images.
METHODS AND PATIENTS
So far, 17 patients have received this procedure with a follow-up of at least 6 months. This cohort consists of 4 women and13 men with an average age of 58.6 years (41-69). The mean duration of the Parkinson’s disease was 10.5 years (6-15). Each patient was implanted bilaterally. Each patient went through a preoperative and a 6-months postoperative clinical evaluation.
RESULTS
The mean 6-months postoperative UPDRS score is 11.8, 8.5 and 5.6, respectively for UPDRS II, III and IV. This represents a reduction of 50.1% for UPDRS II, 79.5% for UPDRS III and 48.9% for UPDRS IV. The mean postoperative L-dopa dose is 635.3 mg (180-1800). Compared to preoperative doses, this represents a decrease of 40.4%. The mean surgery time is 240.6 min (185-325). During postoperative Zeego images acquisition, the mean irradiation of each patient is 21,5 mGy (5-40.3). This is 22.5% less irradiating than a CT. Regarding operative complications, we observe one transient episode of confusion, one implanted pulse generator staphylococcus aureus infection that we had to remove and one bilateral pulmonary embolism. We had to adjust the position of one electrode after a suboptimal position detected on our postoperative Zeego images.
DISCUSSION
Regarding the improvement of clinical status, our results (50.1% for UPDRS II, 79.5% for UPDRS III and 48.9% for UPDRS IV) are comparable with the literature (12-66% for UPDRS II, 25-69% for UPDRS III and 19-71% for UPDRS IV). In our cohort, L-Dopa dose reduction reaches 40.4% and is comparable to figures published in the literature (19-71%). The mean radiation reduction is 22,5% and could have been more important if we had selected the mode Head Care fusion for each postoperative Zeego images acquisition. This mode allows a sufficient image quality for a smaller level of irradiation (reduction of 75%). The mean operative time (240.6 min) is significantly reduced compared to the operative time of our previous procedure under local anesthesia with preoperative clinical evaluation of the patient and postoperative MRI outside operative room (about 7 hours). The originality of our procedure stems from the absence of use of MER, implantation under general anesthesia, targeting and verification of lead position by fused images with preoperative MRI and postoperative fluoroscopy images acquisition without leaving operating theater.
CONCLUSION
In comparaison with other techniques, our procedure shows the same clinical results and offers: a reduced operative time, a lower risk of hemorrhage, less irradiation and a procedure that is more comfortable for patients than local anesthesia.