MDCT Venographic Patterns of Dural Venous Sinus Compromise After Acute Skull Fracture.

OBJECTIVE: Prior studies have shown that skull fractures overlying the dural venous sinuses predispose the patient to an increased risk of dural venous sinus thrombosis (DVST). However, extrinsic compression may also cause sinus compromise and simulate thrombosis. This study set out to evaluate the prevalence and discernibility of DVST versus direct sinus compression in the setting of an overlying skull fracture. MATERIALS AND METHODS: All initial head MDCT venography examinations performed at a level 1 trauma center over an 8-year period were reviewed (n = 347 patients). The examinations that showed an acute fracture overlying a dural sinus were included for review (n = 107 patients). Three neuroradiologists classified the MDCT venography findings as category 0 (normal), 1 (solely sinus compression), 2 (solely intraluminal thrombus), 3 (mixed sinus compression and DVST), or 4 (indeterminate). Clinical outcomes were assessed at 30-45 days after hospital discharge. RESULTS: The percentage of patients in each category was as follows: category 0 (31-33% patients), 1 (38-46%), 2 (5-9%), 3 (8-11%), and 4 (8-13%). Categories 2-4 were more likely in the transverse sinus-sigmoid sinus complex (22-30%) and multiple dural sinuses (47-53%) than in the superior sagittal sinus (SSS) (5%). Interobserver reliability was strong (κ = 0.627-0.772; p < 0.0001). Sinus category was associated with fracture site (p = 0.014) but not with clinical outcome (p = 0.236). CONCLUSION: Sinus compromise is common in patients with overlying skull fractures. Sinus compression can be distinguished from DVST on MDCT venography and is likely more prevalent than previously estimated. The fracture site may in part determine the pattern of compromise because fractures involving the transverse sinus-sigmoid sinus complex or multiple dural sinuses seem more likely to be affected by thrombosis than fractures involving the SSS.

Intracranial vasculature 3D printing: review of techniques and manufacturing processes to inform clinical practice.

BACKGROUND: In recent years, three-dimensional (3D) printing has been increasingly applied to the intracranial vasculature for patient-specific surgical planning, training, education, and research. Unfortunately, though, much of the prior literature regarding 3D printing has focused on the end-product and not the process. In addition, for 3D printing/manufacturing to occur on a large scale, challenges and bottlenecks specific to each modeled anatomy must be overcome. MAIN BODY: In this review article, limitations and considerations of each 3D printing processing step, as they relate to printing individual intracranial vasculature models and providing an active clinical service for a quaternary care center, are discussed. Relevant advantages and disadvantages of the available acquisition techniques (computed tomography, magnetic resonance, and digital subtraction angiography) are reviewed. Specific steps in segmentation, processing, and creation of a printable file may impede the workflow or degrade the fidelity of the printed model and are, therefore, given added attention. The various available printing techniques are compared with respect to printing the intracranial vasculature. Finally, applications are discussed, and a variety of example models are shown. CONCLUSION: In this review we provide insight into the manufacturing of 3D models of the intracranial vasculature that may facilitate incorporation into or improve utility of 3D vascular models in clinical practice.