A Novel Evaluation for Vertebral Artery Course Using 3D Magnetic Resonance Imaging with Computed Tomography -like Bone Contrast and Magnetic Resonance Angiography: A Proof of Concept Study.

OBJECTIVE: Vertebral artery (VA) injury poses a significant risk in cervical spine surgery, necessitating accurate preoperative assessment. This study aims to introduce and validate a novel approach that combines the Fast field echo that resembles a computed tomography using restricted echo spacing (FRACTURE) sequence with Time of Flight (TOF) Magnetic Resonance Angiography (MRA) for comprehensive evaluation of VA courses in the cervical spine. MATERIALS AND METHODS: A total of eight healthy volunteers and two patients participated in this study. The FRACTURE sequence provided high-resolution bone images of the cervical spine, while TOF MRA offered non-invasive vascular imaging. Fusion images were created by merging FRACTURE and MRA modalities to simultaneously visualize cervical spine structures and VA courses. Board-certified orthopedic spine surgeons independently evaluated images to assess the visibility of anatomical characteristics of the VA course by Likert-scale. RESULTS: The FRACTURE-MRA fusion images effectively depicted the extraosseous course of the VA at the craniovertebral junction, the intraosseous course of the VA at the craniovertebral junction, the VA entrance level to the transverse foramen, and the side-to-side asymmetry of bilateral VAs. Additionally, clinical cases demonstrated the utility of the proposed technique in identifying anomalies and guiding surgical interventions. CONCLUSIONS: The integration of the FRACTURE sequence and TOF MRA presents a promising methodology for the precise evaluation of VA courses in the cervical spine. This approach improves preoperative planning for cervical spine surgery with detailed anatomy and is a valuable alternative to conventional methods without contrast agents.

Reproducibility between three-dimensional turbo spin-echo and two-dimensional dual inversion recovery turbo spin-echo for coronary vessel wall imaging in Kawasaki disease.

Magnetic resonance vessel wall imaging is desirable for evaluating Kawasaki disease (KD)-associated coronary arterial lesions. To evaluate the reproducibility of three-dimensional turbo spin-echo (3D-TSE) and two-dimensional dual inversion-recovery turbo spin-echo (2D-DIR-TSE) for coronary vessel wall imaging in KD. Ten patients were prospectively enrolled. Coronary vessel wall imaging with axial-slice orientation 3D-TSE and 2D-DIR-TSE were acquired for cross-sectional images in aneurysmal and normal regions. Lumen area (LA), wall area (WA), and normalized wall index (NWI) of cross-sectional images were measured in both regions. Reproducibility between 3D-TSE and 2D-DIR-TSE was evaluated via intraclass correlation coefficients (ICCs) and Bland-Altman plots. 48 points (aneurysmal, 27; normal, 21) were evaluated. There were high ICCs between 3D-TSE and 2D-DIR-TSE in LA (0.95) and WA (0.95). In aneurysmal regions, 95% limits of agreement were LA, WA, and NWI of - 29.9 to 30.4 mm2, - 18.8 to 15.0 mm2, and - 0.22 to 0.20, respectively. In normal regions, the 95% limits of agreement were LA, WA, and NWI of - 4.44 to 4.38 mm2, - 3.51 to 4.30 mm2, and - 0.14 to 0.16, respectively. No fixed and proportional biases between 3D-TSE and 2D-DIR-TSE images in aneurysmal and normal regions were noted. 3D-TSE was reproducible with conventional 2D-DIR-TSE for coronary vessel wall assessment on KD.

Automated Differentiation Between Osteoporotic Vertebral Fracture and Malignant Vertebral Fracture on MRI Using a Deep Convolutional Neural Network.

STUDY DESIGN: Retrospective study of magnetic resonance imaging (MRI). OBJECTIVES: To assess the ability of a convolutional neural network (CNN) model to differentiate osteoporotic vertebral fractures (OVFs) and malignant vertebral compression fractures (MVFs) using short-TI inversion recovery (STIR) and T1-weighted images (T1WI) and to compare it to the performance of three spine surgeons. SUMMARY OF BACKGROUND DATA: Differentiating between OVFs and MVFs is crucial for appropriate clinical staging and treatment planning. However, an accurate diagnosis is sometimes difficult. Recently, CNN modeling-an artificial intelligence technique-has gained popularity in the radiology field. METHODS: We enrolled 50 patients with OVFs and 47 patients with MVFs who underwent thoracolumbar MRI. Sagittal STIR images and sagittal T1WI were used to train and validate the CNN models. To assess the performance of the CNN, the receiver operating characteristic curve was plotted and the area under the curve was calculated. We also compared the accuracy, sensitivity, and specificity of the diagnosis made by the CNN and three spine surgeons. RESULTS: The area under the curve of receiver operating characteristic curves of the CNN based on STIR images and T1WI were 0.967 and 0.984, respectively. The CNN model based on STIR images showed a performance of 93.8% accuracy, 92.5% sensitivity, and 94.9% specificity. On the other hand, the CNN model based on T1WI showed a performance of 96.4% accuracy, 98.1% sensitivity, and 94.9% specificity. The accuracy and specificity of the CNN using both STIR and T1WI were statistically equal to or better than that of three spine surgeons. There were no significant differences in sensitivity based on both STIR images and T1WI between the CNN and spine surgeons. CONCLUSION: We successfully differentiated OVFs and MVFs based on MRI with high accuracy using the CNN model, which was statistically equal or superior to that of the spine surgeons.Level of Evidence: 4.

Coronary vessel wall visualization via three-dimensional turbo spin-echo black blood imaging in Kawasaki disease.

PURPOSE: To evaluate the feasibility of coronary vessel wall visualization using three-dimensional turbo spin-echo black blood imaging (3D-TSE) in children with Kawasaki disease. MATERIALS AND METHODS: Nine patients (6 girls and 3 boys; mean age ±â€¯standard deviation, 5.6 ±â€¯3.3 years; range, 1.4-10.3 years) were included. Coronary magnetic resonance angiography (MRA) with an axial slice orientation and 3D-TSE with axial and sagittal slice orientations (3D-TSE-axi and 3D-TSE-sag) were acquired for the whole heart. Coronary vessel walls were evaluated separately in aneurysm and normal-proximal regions. The internal diameter and wall thickness of the reformatted cross-sectional images were measured in both the regions. Reproducibility between MRA and 3D-TSE was evaluated via interclass correlation coefficients (ICCs) and Bland-Altman plots. RESULTS: In total, 164 points (aneurysmal regions, 73; normal-proximal regions, 64; normal-distal regions, 27) were evaluated. The ICC for 3D-TSE-axi was higher than that for 3D-TSE-sag (aneurysmal regions, ICC = 0.88 and 0.81; normal-proximal regions, ICC = 0.90 and 0.32, respectively). Bland-Altman plots of the internal diameter via MRA and 3D-TSE-axi showed a wide 95% limit of agreement (-0.13 to 2.89 mm) and significant fixed and proportional biases (P < 0.001 and P = 0.002) in the aneurysmal regions. However, the 95% limit of agreement was narrow (-0.14 to 0.57 mm) in the normal-proximal regions. If 1 mm was set as the cut-off for a thickened wall, wall thickness via 3D-TSE-axi was found to be abnormal across many points (84.0% of aneurysmal regions; 18.4% of normal-proximal regions). CONCLUSIONS: 3D-TSE imaging of the normal-proximal regions of the coronary vessel in individuals with Kawasaki disease was found to be feasible. However, in aneurysmal regions, larger aneurysmal diameters led to an increased bias between MRA and 3D-TSE.