Precision Medicine in Aortic Anastomosis: A Numerical and Experimental Study of a Novel Double-Sided Needle

Background: Hand-sewn anastomosis is a crucial part of aortic reconstruction surgery and significantly affects its outcome. The present study presents a novel, bidirectional surgical needle aimed to improve aortic anastomosis in terms of speed and ease of use. Our objective was to assess the efficacy of the new design in comparison with the conventional needle. Methods: A series of simulations were conducted with COMSOL software in order to perform a fatigue comparative analysis between the new and the conventional needle design. Ease of penetration into a piece of polydimethylsiloxane was evaluated. Lastly, the prototype was tested under in-vitro conditions in comparison with the conventional needle. Results: Based on fatigue analysis, the new needle design improves durability, provided the two tips are equally used. The polytetrafluoroethylene coating improves penetration into the tissue by 7% to 17%, while electropolishing improves penetration up to 19%. When using the novel needle design, the average anastomotic task completion time was significantly reduced by 22% and the overall distance of hand movements was significantly reduced by 20%. Conclusions: The proposed design exhibited a shorter anastomotic time and seems promising in relation to ease of use and simplicity of the anastomotic technique it introduces.

Fatal Case of a Contained Ruptured of the Infrarenal Aorta due to Simultaneous Primary Aortocaval Fistula and Aortoenteric Fistula

We report an extremely rare case of primary aortocaval fistula with simultaneous development of an aortoenteric fistula in a 68-year-old man. The patient developed under oral anticoagulation a spontaneous intracaval aortic rupture. An emergency intervention was performed with a covering of the fistula with an aorto-uniiliac stent graft and a femoro-femoral crossover bypass. One week later, the patient was transferred to our institution with the diagnosis of a psoas abscess and a suspected concomitant aortoenteric fistula. We performed a complete explantation of the endograft and implanted it after extensive debridement an aortobiiliac bypass, made of bovine pericardium. The postoperative course was complicated, first by bleeding from the left iliac anastomosis, and then by bleeding from the proximal aortic anastomosis. The entire graft was explanted and an axillo-femoral bypass was implanted. The patient then developed a multi-organ failure and died 3 months later. If possible, an extended surgical debridement and resection of all infected tissue with in situ reconstruction is the gold standard. However, with this therapy, there is still a high risk of reinfection. Long-term antibiotic management is mandatory.

3D-printed cranial models simulating operative field depth for microvascular training in neurosurgery

Background: The skills required for neurosurgical operations using microsurgical techniques in a deep operating field are difficult to master in the operating room without risk to patients. Although there are many microsurgical training models, most do not use a skull model to simulate a deep field. To solve this problem, 3D models were created to provide increased training in the laboratory before the operating room, improving patient safety. Methods: A patient’s head was scanned using computed tomography. The data were reconstructed and converted into a standard 3D printing file. The skull was printed with several openings to simulate common surgical approaches. These models were then used to create a deep operating field while practicing on a chicken thigh (femoral artery anastomosis) and on a rat (abdominal aortic anastomosis). Results: The advantages of practicing with the 3D printed models were clearly demonstrated by our trainees, including appropriate hand position on the skull, becoming comfortable with the depth of the anastomosis, and simulating proper skull angle and rigid fixation. One limitation is the absence of intracranial structures, which is being explored in future work. Conclusion: This neurosurgical model can improve microsurgery training by recapitulating the depth of a real operating field. Improved training can lead to increased accuracy and efficiency of surgical procedures, thereby minimizing the risk to patients.