Patient-specific virtual three-dimensional surgical navigation for gastric cancer surgery: A prospective study for preoperative planning and intraoperative guidance

Introduction: Abdominal computed tomography (CT) can accurately demonstrate organs and vascular structures around the stomach, and its potential role for image guidance is becoming increasingly established. However, solely using two-dimensional CT images to identify critical anatomical structures is undeniably challenging and not surgeon-friendly. To validate the feasibility of a patient-specific 3-D surgical navigation system for preoperative planning and intraoperative guidance during robotic gastric cancer surgery. Materials and methods: A prospective single-arm open-label observational study was conducted. Thirty participants underwent robotic distal gastrectomy for gastric cancer using a virtual surgical navigation system that provides patient-specific 3-D anatomical information with a pneumoperitoneum model using preoperative CT-angiography. Turnaround time and the accuracy of detecting vascular anatomy with its variations were measured, and perioperative outcomes were compared with a control group after propensity-score matching during the same study period. Results: Among 36 registered patients, 6 were excluded from the study. Patient-specific 3-D anatomy reconstruction was successfully implemented without any problems in all 30 patients using preoperative CT. All vessels encountered during gastric cancer surgery were successfully reconstructed, and all vascular origins and variations were identical to operative findings. The operative data and short-term outcomes between the experimental and control group were comparable. The experimental group showed shorter anesthesia time (218.6 min vs. 230.3 min; P=0.299), operative time (177.1 min vs. 193.9 min; P=0.137), and console time (129.3 min vs. 147.4 min; P=0.101) than the control group, although the differences were not statistically significant. Conclusions: Patient-specific 3-D surgical navigation system for robotic gastrectomy for gastric cancer is clinically feasible and applicable with an acceptable turnaround time. This system enables patient-specific preoperative planning and intraoperative navigation by visualizing all the anatomy required for gastrectomy in 3-D models without any error. Clinical trial registration: Clinicaltrials.gov, identifier NCT05039333.ope

Chylous Ascites After Gastric Cancer Surgery: Risk Factors and Treatment Results

Purpose: Although chylous ascites is a frequent complication of radical gastrectomy for gastric cancer, proper diagnostic criteria and optimal treatment strategies have not been established. This study aimed to identify the clinical features of chylous ascites and evaluate the treatment outcomes. Materials and methods: We retrospectively analyzed the data of patients who underwent radical gastrectomy between 2013 and 2019. Diagnosis was made when milky fluid or elevated triglyceride levels (≥100 mg/dL) appeared in the drains without a preceding infection. The clinical features, risk factors, and treatment outcomes were assessed according to the initial treatment modalities for fasting and non-fasting groups. Results: Among the 7,388 patients who underwent radical gastrectomy for gastric cancer, 156 (2.1%) experienced chylous ascites. The median length of hospital stay was longer in patients with chylous ascites than in those without (median [interquartile range]: 8.0 [6.0-12.0] vs. 6.0 [5.0-8.0], P<0.001). Low body mass index (adjusted odds ratio [aOR]=0.9; P<0.001), advanced gastric cancer (aOR=1.51, P=0.024), open surgery (reference: laparoscopic surgery; aOR=1.87, P=0.003), and extent of surgical resection (reference: subtotal gastrectomy, total gastrectomy, aOR=1.5, P=0.029; proximal gastrectomy, aOR=2.93, P=0.002) were associated with the occurrence of chylous ascites. The fasting group (n=12) was hospitalized for a longer period than the non-fasting group (n=144) (15.0 [12.5-19.5] vs. 8.0 [6.0-10.0], P<0.001). There was no difference in grade III complication rate (16.7% vs. 4.2%, P=0.117) or readmission rate (16.7% vs. 11.1%, P=0.632) between the groups. Conclusions: A fat-controlled diet and medication without fasting provided adequate initial treatment for chylous ascites after radical gastrectomy for gastric cancer.ope

Short-term outcomes and cost-effectiveness of laparoscopic gastrectomy with articulating instruments for gastric cancer compared with the robotic approach

To overcome the limitations of laparoscopic surgery, robotic systems have been commonly used in the era of minimally invasive surgery despite their high cost. However, the articulation of instruments can be achieved without a robotic system at lower cost using articulating laparoscopic instruments (ALIs). Between May 2021 and May 2022, perioperative outcomes following laparoscopic gastrectomy using ALIs versus robotic gastrectomy were compared. A total of 88 patients underwent laparoscopic gastrectomy using ALIs, while 96 underwent robotic gastrectomy. Baseline characteristics were similar between the groups except for a higher proportion of patients with a medical history in the ALI group (p = 0.013). Clinicopathologic and perioperative outcomes were not significantly different between the groups. However, the operation time was significantly shorter in the ALI group (p = 0.026). No deaths occurred in either group. In conclusion, laparoscopic gastrectomy using ALIs was associated with comparable perioperative surgical outcomes and a shorter operation time compared to robotic gastrectomy in this prospective cohort study. © 2023, The Author(s).ope

Changes in failure to rescue after gastrectomy at a large-volume center with a 16-year experience in Korea

Failure to rescue (FTR), the mortality rate among patients with complications, is gaining attention as a hospital quality indicator. However, comprehensive investigation into FTR has rarely been conducted after radical gastrectomy for gastric cancer patients. This study aimed to assess FTR after radical gastrectomy and investigate the associations between FTR and clinicopathologic factors, operative features, and complication types. From 2006 to 2021, 16,851 gastric cancer patients who underwent gastrectomy were retrospectively analyzed. The incidence and risk factors were analyzed for complications, mortality, and FTR. Seventy-six patients had postoperative mortality among 15,984 patients after exclusion. The overall morbidity rate was 10.49% (1676/15,984 = 10.49%), and the FTR rate was 4.53% (76/1676). Risk factor analysis revealed that older age (reference: < 60; vs. 60–79, adjusted odds ratio [OR] 2.07, 95% confidence interval [CI] 1.13–3.79, P = 0.019; vs. ≥ 80, OR 3.74, 95% CI 1.57–8.91, P = 0.003), high ASA score (vs. 1 or 2, OR 2.79, 95% CI 1.59–4.91, P < 0.001), and serosa exposure in pathologic T stage (vs. T1, OR 2.74, 95% CI 1.51–4.97, P < 0.001) were associated with FTR. Moreover, patients who underwent gastrectomy during 2016–2021 were less likely to die when complications occurred than patients who received the surgery in 2006–2010 (OR 0.35, 95% CI 0.18–0.68, P = 0.002). This investigation of FTR after gastrectomy demonstrated that the risk factors for FTR were old age, high ASA score, serosa exposure, and operation period. FTR varied according to the complication types and the period, even in the same institution. © 2023, The Author(s).ope

Infrared Emission Properties and Energy Transfer in Heavy Metal Oxide Glasses co-doped with Ho3+/Yb3

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EWS에 의한 피부 발달의 조절기작

학위논문 (박사)-- 서울대학교 대학원 : 의과학과 의과학전공, 2015. 8. 묵인희.EWS (Ewings Sarcoma) gene encodes a RNA/DNA binding protein that is ubiquitously expressed and involved in various cellular processes. EWS is a nuclear protein, whose nuclear localization is dependent upon its transactivating NH2 terminus. Also, the EWS protein stimulates transcription mediated by the COOH terminal transactivation domain of the cofactor CREB-binding protein (CBP)/p300. EWS deficiency leads to impaired development and early senescence through unknown mechanisms. We found that EWS regulates the expression of Drosha and microRNAs. EWS deficiency resulted in increased expression of Drosha, a well known microprocessor, and increased levels of miR-29b and miR-18b. Importantly, miR-29b and miR-18b were directly involved in the posttranscriptional regulation of collagen IV alpha 1 (Col4a1) and connective tissue growth factor (CTGF) in EWS knock-out (KO) mouse embryonic fibroblast (MEFs) cells. The up regulation of Drosha, miR-29b and miR-18b and the sequential down regulation of Col4a1 and CTGF contributed to the deregulation of dermal development in EWS KO mice. Otherwise, knock-down of Drohsa rescued miRNA-dependent down regulation of Col4a1 and CTGF proteins. Taken together, our data indicate that EWS is involved in posttranscriptional regulation of Col4a1 and CTGF via a Drosha-miRNA-dependent pathway. This finding suggests that EWS plays a novel role in dermal morphogenesis through the modulation of miRNA biogenesis.Abstract i Contents iii List of tables and figures iv List of abbreviations viii Introduction 1 Material and Methods 5 Results 17 Discussion 59 References 65 Abstract in Korean 70Docto

(A) Study on the Right of Damage Compensation in the Korean Monopoly Regulationand Fair Trade Act

학위논문(석사) --서울대학교 대학원 :법학과(경제법전공),2010.2.Maste