Pancreaticoduodenectomy with superior mesenteric artery first-approach combined total meso-pancreas excision for periampullary malignancies: A high-volume single-center experience with short-term outcomes.

Backgrounds/Aims: Pancreaticoduodenectomy (PD) is the only radical treatment for periampullary malignancies. Superior mesenteric artery (SMA) first approach combined with total meso-pancreas (MP) excision was conducted to improve the oncological results. There has not been any previous research of a technique that combines the SMA first approach and total MP excision with a detailed description of the MP macroscopical shape. Methods: We prospectively assessed 77 patients with periampullary malignancies between October 2020 and March 2022 (18 months). All patients had undergone PD with SMA first approach combined total MP excision. The perioperative indications, clinical data, intra-operative index, R0 resection rate of postoperative pathological specimens (especially mesopancreatic margin), postoperative complications, and follow-up results were evaluated. Results: The median operative time was 289.6 min (178-540 min), the median intraoperative blood loss was 209 mL (30-1,600 mL). Microscopically, there were 19 (24.7%) cases with metastatic MP, and five cases (6.5%) with R1-resection of the MP. The number of lymph nodes (LNs) harvested and metastatic LNs were 27.2 (maximum was 74) and 1.8 (maximum was 16), respectively. Some (46.8%) patients had pancreatic fistula, but mostly in grade A, with 7 patients (9.1%) who required re-operations. Some 18.2% of cases developed postoperative refractory diarrhea. The rate of in-hospital mortality was 1.3%. Conclusions: The PD with SMA first approach combined TMpE for periampullary malignancies was effective in achieving superior oncological statistics (rate of MP R0-resection and number of total resected LNs) with non-inferior short-term outcomes. It is necessary to evaluate survival outcomes with long-term follow-up.

Pressure and temperature dependencies of air-perturbed O2 B-band line shapes.

The air-broadened lines from the oxygen B band were measured for the first time in controlled laboratory conditions with a high signal-to-noise ratio using frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) referenced to the optical frequency comb. Spectra measured at various pressures and temperatures were analyzed with an advanced line-shape model, considering the speed-dependence of collisional broadening and shift, and the effect of velocity-changing collisions. The temperature dependence of collisional broadening and shift is determined, whereas no significant temperature dependence of speed-dependent parameters and Dicke narrowing was observed. In addition, we have demonstrated that reasonable estimation of temperature dependence for pressure broadening is possible even from measurements done in single temperature where the speed dependence of pressure broadening was determined. New spectroscopic data improve the accuracy of the air-broadened oxygen B-band spectra description by an order of magnitude.

Total laparoscopic radical antegrade modular pancreato-splenectomy with left-posterior superior mesenteric artery first-approach for distal pancreatic cancer: step-by-step technique with a surgical case report (with video).

INTRODUCTION: Left-sided pancreatic cancers are uncommon but seem more aggressive than tumors of pancreatic head. Radical antegrade modular pancreato-splenectomy (RAMPS) was proved to have safe and effective advantages while comparing with standard retrograde pancreato-splenectomy (SRPS) in recent systematic literature reviews and meta-analyses. Laparoscopic SMA first-approach RAMPS was recently proceeded with optimistic perioperative outcomes. CASE PRESENTATION: Our patient is a 67-year-old female with a medical history of diabetes and hypertension, recruited because of upper left quadrant abdominal pain. She was referred for pancreato-splenectomy because of a 3-cm-sized mass in distal pancreas. We use 5 trocars and the patient placed in a Trendelenburg position. The retroperitoneum is opened at the left-posterior side of the meso-pancreato-duodenum along to the inframesocolic space, so that the anterior surface of the aorta (AO), inferior vena cave (IVC), left renal vein (LRV), left adrenal grand (LAG), and kidney are completely exposed. The inferior border of the pancreas had been dissected and separated from the superior mesenteric vein (SMV) below the pancreatic isthmus, removed the lymph nodes (LNs) groups 14v and 17. Then, dissect of LNs groups 7,8,9,11p,12 en bloc at the superior side of the pancreas. Dissection of LNs group 14p, d or SMA LNs after transecting the pancreas. The operation time was 240 min, the estimated blood loss was 200 ml. With no postoperative complications as well as no diarrhea, the patient was discharged on the POD10 uneventfully. Pathological result: pancreatic ductal adenocarcinoma with T2N1 staging and negative margin (R0). CONCLUSIONS: This technique was safe and effective to perform precise and complete lymphadenectomy and negative posterior resection in total laparoscopic left-posterior SMA first-approach RAMPS for distal pancreatic cancer.

Effect of humidity on the absorption continua of CO2 and N2 near 4 µm: Calculations, comparisons with measurements, and consequences for atmospheric spectra.

We present a theoretical study of the effects of collisions with water vapor molecules on the absorption, around 4 µm, in both the high frequency wing of the CO2 ν3 band and the collision-induced fundamental band of N2. Calculations are made for the very first time, showing that predictions based on classical molecular dynamics simulations enable, without adjustment of any parameter, very satisfactory agreement with the few available experimental determinations. This opens the route for a future study in which accurate temperature-dependent (semi-empirical) models will be built and checked through comparisons between computed and measured atmospheric spectra. This is of interest since, as demonstrated by simulations, neglecting the humidity of air can lead to significant modifications of the atmospheric transmission (and thus also emission) between 2000 and 2800 cm-1.