Artikel
Intraoperative narrowing of the third ventricle on the electrode implantation site in DBS surgery: Is there a consequence for bilateral implantation technique?
Suche in Medline nach
Autoren
Veröffentlicht: | 2. Juni 2015 |
---|
Gliederung
Text
Objective: Brain shift during deep brain stimulation (DBS) surgery can be caused by cerebrospinal fluid (CSF) loss and can be a considerable problem for the precise implantation of DBS leads, especially on the second side. In this study, we want to study the intraoperative variation of the width of the third ventricle and the effect of this variation on the final position of the definitive DBS lead on the second side of surgery.
Method: We included 83 patients selected for bilateral DBS surgery from 2012 to 2014. We measured the width of the third ventricle in preoperative frame based computer tomography (CT) and compared it to immediately postoperative frame based CT. The width of the third ventricle was measured at the level of the mid commissural point. The targeting was performed on MRI based targeting and co-registrated stereotactic CT. The site of implantation of the DBS lead was decided according to micro-recording and intraoperative clinical testing through the Ben-Gun. Patients not implanted in the symmetrical trajectory on the second after implantation of the first side were considered.
Results: Postoperative results were measured in 70 patients. Seven patients were excluded because of artifacts that made it impossible to measure the postoperative diameter of the third ventricle. In six patients postoperative CT data was not available. The preoperative width (mean 6.82 ± SD 2.92mm) of the third ventricle was significant larger than the postoperative diameter (mean 5.64 ± SD 2.79mm); p=0.014, (t-test for independent samples). After clinical testing, 25.6 % of the cases implanted on the first side were not symmetrically implanted on the second side. Of these, 70% were more medial, 20% more lateral and 10% in anterior/posterior direction in contrast to the first implanted side.
Conclusions: Intraoperative CSF loss results in narrowing of the third ventricle in DBS patients, subsequently impacting the site of implantation of the definitive DBS lead on the second side. These findings suggest that intraoperative micro-recording and clinical testing are useful to detect a mapping asymmetry between both sides. Efforts should be made to avoid CSF loss during surgery. A bilateral simultaneous implantation may also prevent intraoperative brain shift during DBS surgery.