Biplanar X-Ray Methods for Stereotactic Intraoperative Localization in Deep Brain Stimulation Surgery

Area of Science:

• Neurosurgery
• Medical Imaging
• Biomedical Engineering

Background:

• Deep brain stimulation (DBS) efficacy relies on accurate electrode placement.
• Current stereotactic intraoperative localization (StIL) methods include fluoroscopy, CT, and MRI.
• The utility of biplanar X-ray for StIL requires detailed evaluation.

Purpose of the Study:

• To assess the feasibility of using orthogonal biplanar X-rays with graphical analysis (GA), ray tracing (RT), and perspective projection (PP) for StIL.
• To compare the accuracy of these X-ray based methods against postoperative CT scans.

Main Methods:

• A retrospective review compared electrode tip positions from postoperative CT scans with intraoperative biplanar X-ray methods.
• Orthogonal biplanar X-rays utilized referential spheres and pins for localization.
• Analysis included graphical analysis (GA), ray tracing (RT), and perspective projection (PP).

Main Results:

• Mean Euclidean errors for DBS electrode position were: GA (1.58 mm ±0.75), RT (0.74 mm ±0.45), and PP (1.07 mm ±0.64).
• GA accuracy improved with ventriculograms; RT and PP correlated with third ventricular structures.
• RT offered stability, PP provided flexibility, and O-arm imaging showed sub-millimeter errors.

Conclusions:

• Graphical analysis, ray tracing, and perspective projection are viable for precise StIL in DBS using biplanar X-ray.
• These techniques can be adapted for other stereotactic procedures and biplanar imaging applications.
• Potential applications include angiograms, radiosurgery, and injection therapeutics.