Stereotactic radiofrequency ablation of a variety of liver masses in children.

BACKGROUND AND AIMS: Surgical resection is currently the cornerstone of liver tumor treatment in children. In adults radiofrequency ablation (RFA) is an established minimally invasive treatment option for small focal liver tumors. Multiprobe stereotactic RFA (SRFA) with intraoperative image fusion to confirm ablation margins allows treatment for large lesions. We describe our experience with SRFA in children with liver masses. METHODS: SRFA was performed in 10 patients with a median age of 14 years (range 0.5-17.0 years) suffering from liver adenoma (n = 3), hepatocellular carcinoma (n = 1), hepatoblastoma (n = 2), myofibroblastic tumor (n = 1), hepatic metastases of extrahepatic tumors (n = 2) and infiltrative hepatic cysts associated with alveolar echinococcosis (n = 1). Overall, 15 lesions with a mean lesion size of 2.6 cm (range 0.7-9.5 cm) were treated in 11 sessions. RESULTS: The technical success rate was 100%, as was the survival rate. No transient adverse effects higher than grade II (Clavien and Dindo) were encountered after interventions. The median hospital stay was 5 d (range 2-33 d). In two patients who subsequently underwent transplant hepatectomy complete ablation was histologically confirmed. Follow-up imaging studies (median 55 months, range 18-129 months) revealed no local or distant recurrence of disease in any patient. CONCLUSIONS: SRFA is an effective minimal-invasive treatment option in pediatric patients with liver tumors of different etiologies.

Cold ischemia contributes to the development of chronic rejection and mitochondrial injury after cardiac transplantation.

Chronic rejection (CR) remains an unsolved hurdle for long-term heart transplant survival. The effect of cold ischemia (CI) on progression of CR and the mechanisms resulting in functional deficit were investigated by studying gene expression, mitochondrial function, and enzymatic activity. Allogeneic (Lew→F344) and syngeneic (Lew→Lew) heart transplantations were performed with or without 10 h of CI. After evaluation of myocardial contraction, hearts were excised at 2, 10, 40, and 60 days for investigation of vasculopathy, gene expression, enzymatic activities, and mitochondrial respiration. Gene expression studies identified a gene cluster coding for subunits of the mitochondrial electron transport chain regulated in response to CI and CR. Myocardial performance, mitochondrial function, and mitochondrial marker enzyme activities declined in all allografts with time after transplantation. These declines were more rapid and severe in CI allografts (CR-CI) and correlated well with progression of vasculopathy and fibrosis. Mitochondria related gene expression and mitochondrial function are substantially compromised with the progression of CR and show that CI impacts on progression, gene profile, and mitochondrial function of CR. Monitoring mitochondrial function and enzyme activity might allow for earlier detection of CR and cardiac allograft dysfunction.

The feasibility of routine use of distal stoma refeeding method in newborns with enterostomy.

Objective: Temporary enterostomies are life-saving in neonatal surgery, however, causing loss of fluid electrolyte, delays in distal bowel adaptation and thus delayed growth of newborns. In this study, we aimed to present the method and clinical results of distal stoma refeeding in premature and mature neonates.Methods: Between January 2012 and December 2017, records of newborn patients who underwent enterostomy and distal stoma refeeding were retrospectively analyzed. Premature and full term neonates who had distal stoma refeeding were evaluated by stoma indications, resection status, duration of total parenteral nutrition use, time of stoma closure operation and surgery findings.Results: Distal stoma refeeding was performed to 23 newborns in study period. Surgical diagnosis of newborns were meconium ileus, focal intestinal perforation, volvulus, necrotizing enterocolitis, ileal atresia, jejunal atresia, and gastroschisis. The bowel resection was performed in 14 patients. Stoma closure was done on the average day 77th. Total parenteral nutrition was given average 28 d and no total parenteral nutrition complication was seen. The stoma closure operations were performed easily.Conclusions: Distal stoma refeeding is safe and successful method. The success of distal stoma refeeding depends on expert team, time, and equipment.

An unusual complication of gastric bypass: perforated duodenal ulcer.

Peptic ulcer in the excluded segment of a gastric bypass has been reported in the literature in only 17 cases. We report a 54-year-old woman with a perforated duodenal ulcer, who had undergone laparoscopic Roux-en-Y gastric bypass surgery for morbid obesity 15 months previously. She was successfully treated by a laparoscopic repair of the perforated duodenal ulcer.

Functional heterogeneity of mitochondria after cardiac cold ischemia and reperfusion revealed by confocal imaging.

BACKGROUND: Mitochondria play a critical role in ischemia-reperfusion injury of the heart. The purpose of the present study was to analyze the intracellular region-specific functional state of mitochondria after cold ischemia-reperfusion in a rat heart transplant model. METHODS: Imaging of the mitochondrial functional state in situ in nonfixed myocardial fibers was performed by confocal microscopy of mitochondrial flavoprotein autofluorescence as redox state indicator; fluorescence of Rhod-2, a specific probe for mitochondrial calcium; and of tetramethylrhodamine ethyl ester fluorescence to monitor the mitochondrial membrane potential. RESULTS: This imaging demonstrated that, in contrast to control fibers, 10-hr heart cold storage, heterotopic cardiac transplantation, and 24-hr reperfusion result in a highly heterogeneous mitochondrial functional state (mitochondrial calcium content, redox state, and inner membrane potential), thus suggesting local permeability transitions and heterogeneous mitochondrial damage. CONCLUSIONS: Imaging of in situ mitochondria allows topologic assessment of mitochondrial defects and heterogeneity, consequently providing new insights into the mechanisms of cardiac ischemia-reperfusion injury.

Robot-assisted laparoscopic cardiomyotomy.

INTRODUCTION: Robot-assisted laparoscopic surgery is an expanding field of medicine. In endoscopic microsurgery particularly, difficult maneuvers such as intracorporeal hand-sewn anastomoses or a narrow operating field are ideal indications for use of an operation robot. PATIENTS AND METHODS: Six patients, four men and two women, underwent robot-assisted laparoscopic cardiomyotomy for achalasia at a tertiary referral center with substantial expertise in robotic surgery. A detailed description of the operation technique is provided, together with a review of the literature. RESULTS: Robot-assisted laparoscopic cardiomyotomy was feasible without any particular problem and the postoperative course of all six patients was uneventful. The operation time was 236 (220-316) minutes, plus 38 (25-47) minutes for setup-time of the robot. At follow-up six months postoperatively, five of the six patients were free of significant dysphagia and all were free of reflux symptoms. DISCUSSION: There are several published reports, series and trials on robot-assisted laparoscopic cardiomyotomy. The general conclusion is that in experienced hands this operation is easy to perform, with a significantly lower rate of mucosal perforations, but that overall costs are higher, including a longer operation time during the learning curve. The avoidance of mucosal lacerations and their possible consequences has to be weighed against higher overall costs. CONCLUSION: Laparoscopic cardiomyotomy is the first standard laparoscopic operation where a clear advantage for use of an operation robot has been proven. Thus, wherever an operation robot is available it should be used for this procedure.

Mitochondrial ischemia-reperfusion injury of the transplanted rat heart: improved protection by preservation versus cardioplegic solutions.

Cold ischemia time and preservation of organs are limited by I/R injury leading to primary nonfunction of the graft. In a rat heart transplant model, we compared cardioplegic St Thomas (ST) to histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin preservation solutions in terms of contractile function, and mitochondrial respiratory and enzymatic defects after prolonged cold ischemia and reperfusion. Contractile function was scored after transplantation and 24 h of reperfusion. Mitochondrial function was investigated by high-resolution respirometry of permeabilized myocardial fibers. Graft performance in terms of contractile function declined with the duration of cold storage. Recovery was significantly improved after 10 h of cold storage in HTK compared with ST (cardiac scores, 3.3+/-0.5 and 1.8+/-0.8, respectively). Tissue lactate dehydrogenase was better preserved in HTK than ST. Increase of tissue water content (edema) was less pronounced in HTK than ST (3.33+/-0.14 and 3.73+/-0.21 mg/mg dry weight, respectively). Similar cardiac scores (2.6+/-0.9 and 2.9+/-1.2, respectively) and mitochondrial respiratory parameters were obtained after preservation in HTK and University of Wisconsin. Decline in contractile function of individual grafts correlated well with loss of mitochondrial respiratory capacity, whereas citrate synthase activity remained largely preserved, indicating specific damage of respiratory complexes. Our data provide evidence for the superiority of preservation solutions versus a cardioplegic solution for prolonged cold storage of the heart. The correlation of graft performance and mitochondrial function indicates the potential of high-resolution respirometry for quantitative assessment of myocardial injury upon cold I/R, providing a basis for diagnostic approaches and evaluation of improved preservation solutions for heart transplantation.