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Introduction Most hemodialysis patients start renal replacement therapy with a central venous catheter (CVC). The left internal jugular vein (LIJV) is the second-choice vein for CVC positioning, after the right IJV. However, to reach the right atrium, the CVC must pass through the left brachiocephalic vein (LBV), which also drains blood from the left arm through the subclavian vein. The purpose of this study is to describe how the anatomy of the central venous system and in particular that of the LBV affects vascular access in hemodialysis patients. Materials and methods Three-dimensional (3D) virtual model reconstructions of the central thoracic veins of three hemodialysis patients were obtained from contrast-enhanced computed tomography scans acquired in the venous phase. The images were exported as DICOM files and loaded on open-source software for visualizing and analyzing the medical imaging (3D Slicer, Windows version 4.8.1). Results As expected, the 3D reconstructions showed that the LBV has a tortuous path with three main angulations that could be associated with external compression and stenosis. These could determine the difficulties and increased risks of venous injury during CVC placement, and an increased risk of medium to long-term catheter-associated vein thrombosis and stenosis. Conclusions The anatomical features of the LBV indicate that the path of a CVC from the LIJV to the right atrium is tortuous and can easily be complicated by vein injury, negatively affecting the creation of future arterio-venous vascular accesses in the left arm.

A 48-year-old female presented to the emergency department with chest pain and collapsed at the front desk. She was reanimated with mechanical chest compression, and after coronary angiography, a left anterior descending/diagonal bifurcation mini-crush stenting was performed. Few hours after the procedure, the patient showed severe hypotension. Abdominal ultrasound and computed tomography (CT) scan evidenced a massive subcapsular liver hematoma (Grade IV, American association for the surgery of trauma (AAST) liver injury scale) of the right lobe with extrahepatic blushing. Transhepatic embolization was attempted but without benefit, so the patient underwent emergency laparotomy for damage control surgery with perihepatic packing. After hemodynamic stabilization, right hepatectomy was performed with a favorable outcome and full recovery. The patient CT scan was retrospectively processed to obtain a virtual model visualizable through a head-mounted display. The virtual reconstruction could improve the comprehension of the injury and the liver surgical anatomy for educational purpose, and it could represent a new tool for preoperative planning.

Introduction. With the availability of low-cost head-mounted displays (HMDs), virtual reality environments (VREs) are increasingly being used in medicine for teaching and clinical purposes. Our aim was to develop an interactive, user-friendly VRE for tridimensional visualization of patient-specific organs, establishing a workflow to transfer 3-dimensional (3D) models from imaging datasets to our immersive VRE. Materials and Methods. This original VRE model was built using open-source software and a mobile HMD, Samsung Gear VR. For its validation, we enrolled 33 volunteers: morphologists (n = 11), trainee surgeons (n = 15), and expert surgeons (n = 7). They tried our VRE and then filled in an original 5-point Likert-type scale 6-item questionnaire, considering the following parameters: ease of use, anatomy comprehension compared with 2D radiological imaging, explanation of anatomical variations, explanation of surgical procedures, preoperative planning, and experience of gastrointestinal/neurological disorders. Results in the 3 groups were statistically compared using analysis of variance. Results. Using cross-sectional medical imaging, the developed VRE allowed to visualize a 3D patient-specific abdominal scene in 1 hour. Overall, the 6 items were evaluated positively by all groups; only anatomy comprehension was statistically significant different among the 3 groups. Conclusions. Our approach, based on open-source software and mobile hardware, proved to be a valid and well-appreciated system to visualize 3D patient-specific models, paving the way for a potential new tool for teaching and preoperative planning.