[A New Preoperative Simulation Using Magnetic Resonance Imaging Bone-Like Imaging with Zero-Echo-Time Sequence].

This study aimed to evaluate the clinical usefulness of zero-echo time(ZTE)-based magnetic resonance imaging(MRI)in planning an optimal surgical approach and applying ZTE for anatomical guidance during transcranial surgery. P atients who underwent transcranial surgery and carotid endarterectomy and for whom ZTE-based MRI and magnetic resonance angiography(MRA)data were obtained, were analyzed by creating ZTE/MRA fusion images and 3D-ZTE-based MRI models. We examined whether these images and models could be substituted for computed tomography imaging during neurosurgical procedures. Furthermore, the clinical usability of the 3D-ZTE-based MRI model was evaluated by comparing it with actual surgical views. ZTE/MRA fusion images and 3D-ZTE-based MRI models clearly illustrated the cranial and intracranial morphology without radiation exposure or the use of an iodinated contrast medium. The models allowed the determination of the optimum surgical approach for cerebral aneurysms, brain tumors near the brain surface, and cervical internal carotid artery stenosis by visualizing the relationship between the lesions and adjacent bone structures. However, ZTE-based MRI did not provide useful information for surgery for skull base lesions, such as vestibular schwannoma, because bone structures of the skull base often include air components, which cause signal disturbances in MRI. ZTE sequences on MRI allowed distinct visualization of not only the bone but also the vital structures around the lesion. This technology is minimally invasive and useful for preoperative planning and guidance of the optimum approach during surgery in a subset of neurosurgical diseases.

Role of amide proton transfer imaging in maximizing tumor resection in malignant glioma: a possibility to take the place of 11C-methionine positron emission tomography.

BACKGROUND: Amide proton transfer (APT) imaging has been proposed as a technique to assess tumor metabolism. However, the relationship between APT imaging and other quantitative modalities including positron emission tomography (PET) has not been investigated in detail. This study aimed to evaluate the clinical usefulness of APT imaging in determining the metabolic status of malignant glioma and to compare findings with those from 11C-methionine (Met)-PET. METHODS: This research analyzed APT imaging data from 20 consecutive patients with malignant glioma treated between January 2022 and July 2023. Patients underwent tumor resection and correlations between tumor activity and intensity of APT signal were investigated. We also compared 11C-Met-PET and APT imaging for the same regions of the perifocal tumor invasion area. RESULTS: Clear, diagnostic APT images were obtained from all 20 cases. Mean APT intensity (APTmean) was significantly higher in the glioblastoma (GBM), IDH wild type group (27.2 ± 12.8%) than in other gliomas (6.0 ± 4.7%; p < 0.001). The cut-off APTmean to optimally distinguish between GBM and other malignant gliomas was 12.8%, offering 100% sensitivity and 83.3% specificity. These values for APTmean broadly matched the tumor-to-contralateral normal brain tissue ratio from 11C-Met-PET analysis (r = 0.66). The APT signal was also observed in the gadolinium non-contrast region on T1-weighted imaging, appearing to reflect the surrounding tumor-infiltrated area. CONCLUSIONS: APT imaging can be used to evaluate the area of tumor invasion, similar to 11C-Met-PET. APT imaging revealed low invasiveness in patients and was useful in preoperative planning for tumor resection, facilitating maximum tumor resection including the tumor invasive area.

Clinical utility of new bone imaging using zero-echo-time sequence in neurosurgical procedures: Can zero-echo-time be used in clinical practice in neurosurgery?

PURPOSE: The purpose of this study was to evaluate the clinical usefulness of zero-echo-time (ZTE)-based magnetic resonance imaging (MRI) in planning the optimum surgical approach and applying ZTE for anatomical guidance during transcranial surgery. METHODS: Eleven of 26 patients who underwent transcranial surgery and carotid endarterectomy and in whom ZTE-based MRI and magnetic resonance angiography (MRA) data were obtained were analyzed by creating ZTE/MRA fusion images and 3D ZTE-based MRI models. We examined whether these images and models can be substituted for computed tomography imaging for neurosurgical procedures. Furthermore, the clinical usability of the 3D ZTE-based MRI models was evaluated by comparing them with actual surgical views. RESULTS: Zero-echo-time/MRA fusion images and 3D ZTE-based MRI models clearly illustrated the cranial and intracranial morphology without radiation exposure or the use of iodinated contrast medium. The models allowed determination of the optimum surgical approach to cerebral aneurysms, brain tumors near the brain surface, and cervical internal carotid artery stenosis by visualizing the relationship of lesions with adjacent bone structures. However, ZTE-based MRI did not provide useful information for surgery for skull base lesions such as vestibular schwannoma because bone structures of the skull base often include air components, which cause signal disturbance in MRI. CONCLUSIONS: Zero-echo-time sequences on MRI allowed distinct visualization of not only bone but also vital structures around the lesion. This technology has low invasiveness for patients and was useful for preoperative planning and guidance of the optimum approach during surgery in a subset of neurosurgical diseases.