Potential Usefulness of Three-dimensional Navigation Tools for the Resection of Intra-abdominal Recurrence of Colorectal Cancer.

PURPOSE: Complete resection of intra-abdominal recurrence of colorectal cancer is difficult because of complex anatomical changes following primary surgery and indefinite cancer demarcation. Here, we demonstrate the effect of surgery using three-dimensional (3D) printed model and 3D virtual images on the achievement of complete resection. METHODS: We enrolled 11 cases who had undergone combined resection of adjacent organs for colorectal cancer recurrence, including localized peritoneal dissemination of colon cancer and local recurrence of rectal cancer, between January 2016 and July 2018. We created 3D virtual images of nine cases and 3D models of two cases and used them for intraoperative navigation. RESULTS: Simulation and navigation using 3D technologies potentially helped the surgeons to comprehend the complex anatomy and perform challenging surgeries. Macroscopic negative margins were achieved in all cases, including R0 resection in 8 of the 11 cases. CONCLUSION: 3D navigation tools are potentially useful to complete the resection of intra-abdominal recurrence of colorectal cancer.

Vascular anatomy of the splenic flexure, focusing on the accessory middle colic artery and vein.

AIM: Recently, the accessory middle colic artery (AMCA) has been recognized as the vessel that supplies blood to the splenic flexure. However, the positional relationship between the AMCA and inferior mesenteric vein (IMV) has not been evaluated. Herein, we aimed to evaluate the anatomy of the AMCA and the splenic flexure vein (SFV). METHOD: Two hundred and five patients with colorectal cancer who underwent enhanced CT preoperatively were enrolled in the present study. The locations of the AMCA and IMV were evaluated, focusing on the positional relationship between the vessels and pancreas - below the pancreas or to the dorsal side of the pancreas. RESULTS: The AMCA was observed in 74 (36.1%) patients whereas the SFV was found in 177 (86.3%) patients. The left colic artery (LCA) was the major artery accompanying the SFV in 87 (42.4%) of patients. The AMCA accompanied the SFV in 65 (32.7%) patients. In 15 (7.8%) patients, no artery accompanied the SFV. The origin of the AMCA was located on the dorsal side of the pancreas in 15 (20.3%) of these 74 patients. Similarly, the destination of the IMV was located on the dorsal side of the pancreas in 65 (31.7%) of patients. CONCLUSION: The SFV was observed in most patients, and the LCA or AMCA was the common accompanying artery. In some patients these vessels were located on the dorsal side of the pancreas and not below it. Preoperative evaluation of this anatomy may be beneficial for lymph node dissection during left-sided hemicolectomy.

Tuning surface grafting density of CeO2 nanocrystals with near- and supercritical solvent characteristics.

In this work, the solvent effect on the synthesis of CeO2 nanocrystals synthesized in near- and supercritical alcohols is discussed. The materials prepared displayed a unique morphology of small nanocrystals (<10 nm) aggregated into larger nanospheres (∼100-200 nm). In such syntheses, alcohol molecules directly interact with the nanocrystal surface through alkoxide and carboxylate bondings. The grafting density was quantified from the weight loss measured using thermogravimetric analysis. A direct correlation between the grafting density and the alcohol chain length can be established. It was demonstrated that the shorter the alcohol chain length (i.e. methanol), the higher the surface coverage is. This trend is independent of the synthesis mode (batch or continuous). Additionally, an influence of the grafting density on the resulting nanocrystal size was established. It is suggested that the surface coverage has a high influence on the early stages of the nucleation and growth. Indeed, when high surface coverages are reached, all surface active sites are blocked, limiting the growth step and therefore leading to smaller particles. This effect was noticed with the materials prepared in the continuous mode where shorter reaction time was performed.