Three-dimensional reconstruction imaging by C-arm computed tomography accurately visualizes in-stent neointimal formation in patients with stent-assisted coil embolization.

Background: Stent apposition to the vessel wall and in-stent neointimal formation after stent-assisted coil embolization for intracranial aneurysm are important factors associated with postoperative thromboembolic complications. No assessment methods have been established to depict 3-dimensional (3D) all-round in-stent neointimal formation. Objective: To demonstrate the superiority of Dyna-3D imaging assessment as a modality for all-round ISNF in comparison with conventional two-dimensional digital subtraction angiography (2D-DSA). Methods: Consecutive patients who underwent braided stent-assisted coil embolization for unruptured aneurysm between November 2016 and September 2021 were enrolled. Radiological assessments for stent apposition to the parent vessel after stent deployment and in-stent neointimal formation after 3 months were obtained. Dyna-3D was reconstructed by overlapping a plain image showing stent struts with a rotational DSA image showing the vessel lumen. Reconstructed Dyna-3D images can be rotated to any angle on the screen to evaluate to stent apposition around the vessel and in-stent neointimal formation in 3D, for comparison with 2D-DSA evaluations. Results: Among the 73 patients enrolled, 70 patients (96%) showed complete stent wall apposition on Dyna-3D. Higher intra-rater agreement was confirmed on assessment of in-stent neointimal formation with Dyna-3D (Cohen's κ = 0.811) than with conventional 2D-DSA (Cohen's κ = 0.517). in-stent neointimal formation could not be confirmed on conventional imaging in 9 cases (16%) and on Dyna-3D in 2 cases (3%). The number of in-stent neointimal formations rated as stent wire completely outside the endothelial line was significantly higher with Dyna-3D than with 2D-DSA (p = 0.0001). Conclusion: All-round 3D evaluation by Dyna-3D imaging appears useful for confirming in-stent neointimal formation after braided stent deployment in patients after stent-assisted coil embolization.

Usefulness of the Multimodal Fusion Image for Visualization of Deep Sylvian Veins.

The preoperative assessment of cerebral veins is important to avoid unexpected cerebral venous infarction in the neurosurgical setting. However, information is particularly limited regarding deep Sylvian veins, which occasionally disturb surgical procedures for cerebral anterior circulation aneurysms. The predictability of detecting deep Sylvian veins and their tributaries using a modern multimodal fusion image was aimed to be evaluated. Moreover, 51 patients who underwent microsurgery for unruptured cerebral aneurysms with Sylvian fissure dissection were retrospectively reviewed. The visualization of the four components of the deep Sylvian veins in conventional computed tomography (CT) venography and multimodal fusion images was evaluated. To compare the detection accuracy among these radiological images, the sensitivity and specificity for the detection of each of the four venous structures were calculated in comparison with those of intraoperative inspections. The kappa coefficients were also measured and the inter-rater agreement for each venous structure in each radiological image was examined. In all veins, the multimodal fusion image exhibited a high detection rate without statistical difference from intraoperative inspections (P = 1.0). However, CT venography exhibited a low detection rate with a significant difference from intraoperative inspections in the common vertical trunk (P = 0.006) and attached vein (P = 0.008). The kappa coefficients of the fusion image ranged from 0.73 to 0.91 and were superior to those of CT venography for all venous structures. This is the first report to indicate the usefulness of a multimodal fusion image in evaluating deep Sylvian veins, especially for the detection of nontypical, relatively small veins with large individual variability.

Complex combination of femoropopliteal occlusive disease and arteriovenous fistula treated using color-coded digital subtraction angiography.

Any quantitative assessment of blood flow using conventional angiography remains impossible with current technology. Physicians decide the clinical end point of a procedure by subjective interpretation. Color-coded digital subtraction angiography has been invented to meet this demand and is used primarily in neuroradiology. This report presents the endovascular treatment of a rare complex combination of peripheral artery disease and arteriovenous fistula using guidance of blood flow parameters, such as area under the curve.

Posterior atlantoaxial fusion using a C2 transverse foramen-penetrating screw: A technical note.

BACKGROUND: Although recent development of screw instrumentation techniques for rigid fixation of the atlantoaxial joint has increased surgical options, patients in whom screws of any type cannot be safely placed are sometimes encountered. We present a unique surgical technique for C1-2 transarticular screw placement utilizing a novel trajectory. METHODS: A 35-year-old male with a history of Down's syndrome and cognitive dysfunction with hyperkinesis spontaneously developed rapid onset of tetraparesis and gait disturbance. Radiographs of the cervical spine revealed atlantoaxial subluxation (AAS) that could not be reduced. Computed tomography (CT) of the head showed multiple subacute cerebral infarctions in the territory of the right vertebral artery (VA). Three-dimensional CT angiography of the craniovertebral junction additionally confirmed right VA occlusion at the C2/3 level, a left C2 origin of the posterior inferior cerebellar artery, and hypoplasia of the bilateral C2 pedicles/C2 lamina. Because traditional screw-placement was not feasible, we performed a unique atlantoaxial fusion utilizing a C2 transverse foramen-penetrating screw with iliac bone grafting performed under neuronavigation. RESULTS: The postoperative course was uneventful, and the patient regained the ability to ambulate, returning to his previous level of function. The CT of the cervical spine 12 months postoperatively showed rigid bony C1-C2 fusion, without recurrence of stroke. CONCLUSION: We introduced a novel C1-C2 transarticular screw-placement technique in which the trajectory went through the ipsilateral VA foramen due to already extent VA occlusion.