Robotic complete mesocolic excision for transverse colon cancer can be performed with a morbidity profile similar to that of conventional laparoscopic colectomy.

BACKGROUND: In minimally invasive surgery, complete mesocolic excision (CME) for transverse colon cancer is challenging; thus, non-CME resections are commonly preferred when laparoscopy is used. Robotic technology has been developed to reduce the limitations of laparoscopy. The aim of our study was to evaluate whether robotic CME for transverse colon cancer can be performed with short-term outcomes similar to those of laparoscopic conventional colectomy (CC). METHODS: A retrospective review of 118 consecutive patients having robotic CME or laparoscopic CC for transverse colon cancer in two specialized centers between May 2011 and September 2018 was performed. Perioperative 30-day outcomes of the two procedures were compared. RESULTS: There were 38 and 80 patients in the robotic CME group and laparoscopic CC group, respectively. The groups were comparable regarding preoperative characteristics. Intraoperative results were similar, including blood loss (median 50 vs 25 ml), complications (5.3% vs 3.8%), and conversions (none vs 7.5%). The rate of intracorporeal anastomosis was significantly higher (86.8% vs 20.0%), mean operative time was longer (325.0 ± 123.2 vs 159.3 ± 56.1 min (p < 0.001), and the mean number of harvested lymph nodes was higher in the robotic CME group (46.1 ± 22.2 vs 39.1 ± 17.8, p = 0.047). There were only minor differences in length of hospital stay (7.2 ± 3.1 vs 7.9 ± 4.0 days), anastomotic leak (none vs 2.6%), bleeding (none vs 1.3%), surgical site infections (10.5% vs 12.5%), and reoperations (2.6% vs 6.3%). CONCLUSIONS: Robotic CME can be performed with a similar morbidity profile as laparoscopic CC for transverse colon cancer along with a higher rate of intracorporeal anastomosis, and higher number of lymph nodes retrieved, but longer operative times.

The da Vinci Xi system for robotic total/subtotal colectomy vs. conventional laparoscopy: short-term outcomes.

BACKGROUND: The aim of this study was to evaluate the feasibility of robotic total/subtotal colectomy procedures with the Xi robot and to compare its short-term outcomes with those of conventional laparoscopy. METHODS: Between October 2010 and September 2018, consecutive patients with colonic neoplasia, inflammatory bowel disease, familial adenomatous polyposis or colonic inertia who underwent elective robotic or laparoscopic total/subtotal abdominal colectomy at two specialized centers in Turkey were included. Data on perioperative characteristics and 30-day outcomes were compared between the two approaches. RESULTS: There were a total of 82 patients: 26 and 56 patients in the robotic and laparoscopic group, respectively (54 men and 28 women, mean age 54.7 ± 17.4 years). The groups were comparable regarding preoperative characteristics. All the robotic procedures were completed with a single positioning of the robot. Estimated blood loss (median, 150 vs 200 ml), conversions (0% vs 14.3%), and complications (0% vs 7.1%) were similar but operative time was significantly longer in the robotic group (median, 350 vs 230 min, p < 0.001). No difference was detected in the length of hospital stay (7.9 ± 5.7 vs 9.5 ± 6.0 days, p = 0.08), anastomotic leak (3.8% vs 8.3%), ileus (15.4% vs 19.6%), septic complications, reoperations (7.7% vs 12.5%), and readmissions (19.2% vs 12.5%). The number of harvested lymph nodes in the subgroup of cancer patients was significantly higher in the robotic group (median, 66 vs 50, p = 0.01). CONCLUSIONS: In total/subtotal colectomy procedures, the robotic approach with the da Vinci Xi platform is feasible, safe, and associated with short-term outcomes similar to laparoscopy but longer operative times and a higher number of retrieved lymph nodes.

Ultrafast Photodetection in the Quantum Wells of Single AlGaAs/GaAs-Based Nanowires.

We investigate the ultrafast optoelectronic properties of single Al0.3Ga0.7As/GaAs core-shell nanowires. The nanowires contain GaAs-based quantum wells. For a resonant excitation of the quantum wells, we find a picosecond photocurrent which is consistent with an ultrafast lateral expansion of the photogenerated charge carriers. This Dember-effect does not occur for an excitation of the GaAs-based core of the nanowires. Instead, the core exhibits an ultrafast displacement current and a photothermoelectric current at the metal Schottky contacts. Our results uncover the optoelectronic dynamics in semiconductor core-shell nanowires comprising quantum wells, and they demonstrate the possibility to use the low-dimensional quantum well states therein for ultrafast photoswitches and photodetectors.