Application of mobile CT for neurosurgical operation and stereotactic radiotherapy

Abstract

We have applied an automated helical computerized tomography (CT) scanner gantry on floor-embedded rails in an ordinary operating room to estimate the extent of resection by intra-operative CT (In-CT). The same mobile CT scanner system was also installed in an ordinary radiotherapy room to determine the targets of stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (SRT). In-CT images, including reconstructed 2D CT (coronal and sagittal) and 3D CT, were obtained within 15 min without transporting patients for 324 operations, mainly 156 brain tumors and 69 cervical spinal degenerative disorders. For radiosurgery, the isocenter of irradiation can be aligned with the center of the mobile CT gantry by rotating the couch. SRS using this system was applied to 40 intracranial lesions. SRT also has been utilized for 10 intracranial and 16 extra-cranial whole body lesions. In-CT images were readily available to assess the extent of removed lesions of both brain tumors and cervical spinal disorders. In cases of cervical spinal disorders, more than 50% of cases required further removal of lesions after assessment of first In-CT. A mobile CT enabled SRS and SRT to be performed quickly and accurately with image fusion using MRI or angiography, and micro-multileaf collimators.