Posterior Cervical Foraminotomy Using Preoperative Magnetic Resonance Imaging Combined with Intraoperative Real-Time Ultrasonography: Technical Note and Initial Experience.

Abstract

Posterior cervical foraminotomy for cervical spondylotic radiculopathy requires precise neural decompression while maintaining facet joint integrity. Ideally, the achievement of appropriate nerve root decompression should be confirmed using intraoperative computed tomography or other imaging modalities, although this is not generally done because of the need to avoid radiation exposure and/or because the procedure is very widely performed, even at facilities without expensive equipment. Magnetic resonance imaging (MRI)-ultrasound (US) fusion imaging has the potential to provide a simple radiation-free method of confirming successful neuroforaminal decompression. Preoperative T2-weighted MRI scans were obtained in a position consistent with the intraoperative alignment and were integrated with the intraoperative field-tracked US system during surgery. We used the fusion imaging to provide real-time visualization of decompression progress. This technique takes advantage of the inability of US to visualize the tissues beneath the bone; visualization of the neural foramen previously obscured by bone after foraminotomy indicates successful decompression. Furthermore, fusion MRI ensures that sufficient decompression was achieved along the entire course of the nerve root without unnecessarily resecting the facet joints. The technique was applied to four foraminal levels in three patients with cervical radiculopathy. All patients showed significant symptomatic improvement postoperatively. Postoperative computed tomography scans confirmed adequate decompression beyond stenotic regions, with facet joint preservation matching intraoperative estimates. MRI-US fusion imaging enables radiation-free real-time confirmation of neural decompression during posterior cervical foraminotomy while helping preserve facet joint integrity. This novel approach helps ensure surgical certainty in an inexpensive noninvasive manner.