Virtual Surgical Planning of Deep Circumflex Iliac Artery Flap for Midface Reconstruction

ObjectiveMidface reconstruction is challenging for functional and esthetic reasons. The present study analyzed the effect of virtual surgical planning (VSP) of the deep circumflex iliac artery (DCIA) flap for midface reconstruction.Patients and MethodsThirty-four patients who underwent midface reconstruction with the DCIA flap were included in this retrospective study. Of the 34 patients, 16 underwent preoperative VSP, which used a three-dimensionally printed surgical guide, computer-assisted navigation system, and pre-bent titanium implants to transfer VSP into real-world surgery. The other 18 patients underwent traditional midface reconstruction. The following were compared between the two groups: bony contact rate in the buttress region (BCR), dental arch reconstruction rate (DAR), surgical approach, position of vascular anastomosis, and dental implantation rate. The independent-samples t-test and Fisher’s exact test were used for analysis. P < 0.05 was considered statistically significant.ResultsIn total, 12 males and 22 females were included in this study. All patients underwent midface reconstruction using the DCIA flap at the same institution. The median age of patients was 33 years (range: 16–68 years). The average BCR and DAR values in the VSP group were 59.4% ± 27.9% and 87.5% ± 18.9%, respectively, which were significantly higher compared with the non-VSP group (P = 0.049 and P = 0.004, respectively). The dental implantation rate in the VSP group (50.0%) was significantly higher compared with the non-VSP group (11.1%; P = 0.023). The intraoral approach for tumor ablation and vascular anastomosis was the most frequent choice in both groups. There was no significant difference between the two groups. All patients were satisfied with facial symmetry postoperatively.ConclusionsVSP could effectively augment the effect of midface reconstruction with the DCIA flap. Stronger bone contact in the buttress region and higher DAR provide more opportunity for dental implantation, which might be the best solution to improve masticatory function in patients with midface defects.

Analysis of the Peak Systolic Velocity in the Transplant Renal Artery Anastomosis to Determine Normal Values in Patients Without Graft Dysfunction

Objective: The primary purpose is to define the mean renal artery anastomosis peak systolic velocity (RAA PSV) and the renal artery anastomosis to external iliac artery ratio (RAA-to-EIA) of renal transplant recipients without graft dysfunction. Moreover, to determine associations with type of vascular anastomosis and type of graft. Materials and Methods: This is a single-center retrospective analysis of kidney transplant recipients. Recorded variables included recipient age, type of vascular anastomosis, type of graft, RAA PSV, and external iliac artery PSV (EIA PSV). Such variables were evaluated on different postoperative follow-up periods. Results: There was a high degree of reliability between the RAA PSV and EIA PSV ( P < .001). The mean RAA PSV was 174 cm/s ± 72.9 cm/s with 95% confidence interval (CI) (162.2 cm/s-185.5 cm/s]. Conclusion: This study highlights the importance of determining the normal range of RAA PSV and showed that a high PSV does not necessarily indicate dysfunction.

Reliability of Temporal Vascular Anastomosis and Techniques for Better Outcomes

Background Although there are several potential recipient vessels in the neck, those in the temporal region are limited. In skull base reconstruction, there are difficulties associated with the anastomosing recipient vessels in the neck region since long nutrient vessels are needed in the flap. We evaluated the reliability of temporal vascular anastomosis by comparing surgical outcomes between reconstructive methods and examined which surgical procedures may achieve better results. Methods We examined the medical records of free tissue transfer cases between April 2007 and March 2018. Seventy-three surgeries were performed in the temporal region, including skull base reconstruction in 48, head and neck reconstruction (without skull base) in 16, and secondary surgery for head deformities in nine cases. In total, 445 neck surgeries were performed. Postoperative complications were retrospectively analyzed. Results The postoperative complication rates were 8.2 and 2.7% for all temporal and neck surgeries, respectively. There were no arterial complications in the temporal region and all of the six postoperative anastomotic complications were due to venous thrombosis. In contrast, there were 12 cases of vascular anastomotic complications, with six cases each of arterial and venous thrombosis in the neck. In the temporal region, the complication rate was 2.1% for skull base reconstruction, 11% for secondary revision, and 25% in head and neck reconstruction. The corresponding values for middle temporal vein (MTV) usage rates were 54, 22, and 25%. In skull base reconstruction, a coronal incision was made in all cases. A more frequent use of the MTV was associated with a reduced complication rate. Conclusion The low complication rate in the temporal region was attributed to the wide surgical field and low tension of anastomotic vessels. Multiple venous anastomoses, including those of the MTV, are recommended to prevent complications.

The Effect of Perioperative Blood Transfusions on Microvascular Anastomoses

Introduction: Perioperative transfusions are associated with complications of free flaps. The purpose of the present study was to find out whether there is a significant relationship between the risk of developing complications in vascular anastomoses and the history of transfusions. Methods: We studied 372 patients retrospectively with microsurgical reconstruction between 2009 and 2017 with regards to the number of red blood cell concentrates transfused. Complications were analyzed relative to flap loss and complications in microvascular anastomoses. Results: 130 patients (34.9%) received blood transfusions. Some 55% of them were transfused between the day of the intervention and the first postoperative day. Ninety-six patients were reoperated on (25.7%). Of those, thirty-six patients (37.5%) corresponded to anastomosis failure. The percentage of patients transfused among those who required reoperation was 55.2%. The percentage of patients transfused among those who were reoperated on within the first 72 h due to an alteration in the anastomosis was 60.6%, while it was 25.6% (Chi square P = 0.0001) for the rest of the patients. Conclusions: Although there is a strong association between transfusion and vascular anastomosis failure, it is not possible to establish the causation between the two.

Svep1 stabilizes developmental vascular anastomosis in reduced flow conditions

We report the discovery that flow and Svep1 are modulator of vessel anastomosis during developmental angiogenesis in zebrafish embryos. We show that loss of Svep1 and blood flow reduction both contribute to defective anastomosis of intersegmental vessels. We show that this defect in primary angiogenic sprouts is associated with an expansion of Apelin-positive tip cells and with reduced formation and lumenisation of the dorsal longitudinal anastomotic vessel. Mechanistically, our results suggest that flow and Svep1 act synergistically to modulate vascular network formation in the zebrafish trunk.