METHOD: The method based on constructing atlases for the portal and the hepatic veins bifurcations, the atlas is used to localize the corresponding vein in each segmented vasculature using atlas matching. Point-based registration is used to deform the mesh of atlas to the vein branch. Three-dimensional distance map of the hepatic veins is constructed; the fast marching scheme is applied to extract the centerlines. The centerlines of the labeled major veins are extracted by defining the starting and the ending points of each labeled vein. Centerline is extracted by finding the shortest path between the two points. The extracted centerline is used to define the trajectories to plot the required planes between the anatomical segments.
RESULTS: The proposed approach is validated on the IRCAD database. Using visual inspection, the method succeeded to extract the major veins centerlines. Based on that, the anatomic segments are defined according to Couinaud segmental anatomy.
CONCLUSION: Automatic liver segmental anatomy identification assists the surgeons for liver analysis in a robust and reproducible way. The anatomic segments with other liver structures construct a 3D visualization tool that is used by the surgeons to study clearly the liver anatomy and the extension of the cancer inside the liver.
MATERIAL AND METHODS: A total of 34 chronic renal disease patients (stage 3 and 4) were recruited in a randomized controlled trial. Handgrip exercise was performed for 8 weeks in the intervention group. Handgrip-strength measurement and distal forearm cephalic vein diameter of a non-dominant hand with and without tourniquet was recorded (measurement is taken 1 cm proximal to the radial styloid).
RESULTS: After 8 weeks, the mean cephalic vein diameter in the intervention group increased from 1.77 and 1.97 mm to 2.15 and 2.43 mm, without and with a tourniquet, respectively (p < 0.05). There is also a significant change in the mean diameter of distal forearm cephalic vein (p < 0.05) in the intervention group when measured in both the absence (mean change 0.39 ± 0.06 mm vs 0.01 ± 0.02 mm) and the presence of tourniquet (mean change 0.47 ± 0.07 mm vs 0.01 ± 0.01 mm).
CONCLUSION: These findings suggest that non-invasive handgrip exercise can increase in the diameter of the distal forearm cephalic vein, thereby increasing the rate of successful arteriovenous fistula creation.
METHODS: Both patients had features of difficult airway, American Society of Anesthesiologists (ASA) physical status class III and central venous occlusive disease. The common approach, i.e., ultrasound-guided supraclavicular brachial plexus block was technically difficult with inherent risk of vascular puncture due to dilated venous collaterals at the supraclavicular area possibly compromising block quality. The risk of general anesthesia (GA) was significant as patients were morbidly obese with possible risk of obstructive sleep apnea postoperatively. As an alternative, we performed the ultrasound-guided costoclavicular approach infraclavicular brachial plexus block with 20 mL local anesthetic (LA) ropivacaine 0.5% delivered at the identified costoclavicular space using in-plane needling technique. Another 10 mL of LA was infiltrated along the subcutaneous fascia of the proximal medial aspect of arm.
RESULTS: Both surgeries of >2 hours' duration were successful, without the need of further local infiltration at surgical site or conversion to GA.
CONCLUSIONS: Ultrasound-guided costoclavicular approach can be an alternative way of providing effective analgesia and safe anesthesia for vascular access surgery of the upper limb.