Epineural adipose-derived stem cell injection in a sciatic rodent model.

BACKGROUND: The aim was to evaluate the regenerative effect of epineural injection of rat ASCs (rASCs) in three different settings of acute and chronic compression in a rat sciatic nerve model. METHODS: Acute compression (60 s) with a vessel clamp over a distance of 1 mm (group 1) or 10 mm (group 2), as well as chronic compression with a permanent remaining, nonabsorbable polymeric clip over a distance of 1 mm (group 3) was performed. Depending on the group, either 5 × 106 rASCs or the same volume (25 µl) of culture medium (CM) was injected with a 30G needle in the epineurium at the time of compression. Outcome measures were functional gait evaluations, imaging analysis, histomorphometric analyses, and muscle weight. RESULTS: The rats in group 2 had a better function than those with group 1 at one and especially at 2 weeks. After 4 weeks however, almost all rats were close to a normal function. There was a similar Muscle Weight Ratio (MWR) after 2 weeks in all groups, whereas after 4 weeks, the MWR in group 3 was lower compared with group 1 and 2. Histomorphometric analysis showed a better myelination in group 1 & 2 compared to group 3 after 4 weeks. ASCs have a beneficial effect on myelin thickness (G-Ratio). CONCLUSIONS: We successfully evaluated the regenerative effect of epineural injection of rASCs in three different settings of acute and chronic compression. However, there were no significant differences in outcomes between the ASC-treated groups and control groups.

Preoperative Two-Dimensional Size of Glioblastoma is Associated with Patient Survival.

BACKGROUND: Although tumor size affects survival of patients with lower-grade glioma, a prognostic effect on patients with glioblastoma remains to be established. METHODS: We performed a retrospective analysis of 61 patients using volumetric data of tumor compartments of 61 patients obtained by preoperative magnetic resonance images using the visual ABC/2 method. Preoperative enhancing, nonenhancing, necrosis, and edema volume, the preoperative tumor area (TA) as a product of the 2 largest tumor diameters perpendicular to each other on axial T1-weighted postcontrast images, as well as postoperative enhancing residual volumes, were measured. Multivariable Cox proportional hazard models were used to associate these parameters with overall survival, adjusting for potential confounders. RESULTS: The median preoperative enhancing tumor volume was 18.2 mL (interquartile range, 8.2-41.7 mL); the median remnant tumor volume was 1.3% (interquartile range, 0.0%-42.9%). During follow-up, 59 patients (92%) died; median survival time and median follow-up time were both 404 days. We found a statistically significant multiplicative effect of TA on survival: the hazard ratio (HR) was increased by 1.096 per unit increase of 200 mm2 (95% confidence interval [CI], 1.027-1.170; P < 0.01). The effect of remnant tumor on HR increased multiplicatively by 1.013 (95% CI, 1.001-1.026; P = 0.04) per unit increase of 1 log (day) and 1% in tumor remnant. HR associated with age at surgery increased by 1.503 per 5 years of age (95% CI, 1.243-1.817; P < 0.01). CONCLUSIONS: Preoperative TA proved to be the only glioblastoma size parameter that affects patient survival.

From Bedside to Bench: The Effect of Muscular Denervation on Fat Grafting to the Breast by Comparing Take Rate, Quality, and Longevity.

BACKGROUND: Autologous fat grafting (AFG) to the breast is a frequent procedure in aesthetic and reconstructive surgery. Despite pure volume gain, questions remain regarding the engraftment rate, quality, and longevity. Little is known about the role of recipient tissue or innervation of the grafted area. OBJECTIVES: The goal of this study was to determine the optimal recipient layer and muscular pretreatment of AFG. METHODS: Fat was grafted to the breast, pectoralis muscle, or adjacent subcutaneous tissue of 42 rats. Nerve treatment included excision of a nerve segment, botulinum toxin (BTX) injection, or no treatment. Magnetic resonance imaging (MRI) and histological workup were carried out after 2 and 6 weeks. RESULTS: Six weeks after AFG, the proportion of viable fat cells within the grafted fat stayed high (median, [IQR]: 81% [72% to 85%]). The signs of inflammation decreased over time. Intramuscular grafting with intact nerves had a decreasing effect on the viability of the grafted cells compared with subcutaneous treatment (-10.21%; 95% confidence interval [-21.1 to 0.68]). CONCLUSIONS: If utilized on an intact nerve, intramuscular injection may lead to inferior results. If the nerve was cut or treated with BTX; however, intramuscular injection tends to be superior. These findings may prove interesting for future studies and eventual clinical application.

Laparoscopic Roux-en-Y gastric bypass versus laparoscopic mini gastric bypass in the treatment of obesity: study protocol for a randomized controlled trial.

BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (LRYGB) is considered the gold standard in bariatric surgery, achieving durable long-term weight loss with improvement of obesity-related comorbidities. Lately, the laparoscopic mini gastric bypass (LMGB) has gained worldwide popularity with similar results to LRYGB in terms of weight loss and comorbidity resolution. However, there is a lack of randomized controlled trials (RCT) comparing LMGB and LRYGB. This article describes the design and protocol of a randomized controlled trial comparing the outcomes of these two bariatric procedures. METHODS/DESIGN: The trial is designed as a single center, randomized, patient and observer blinded trial. The relevant ethics committee has approved the trial protocol. To demonstrate that LMGB is not inferior to LRYGB in terms of excess weight loss (EWL) the study is conducted as a non-inferiority trial with the sample-size calculations performed accordingly. EWL 12 months after surgery is the primary endpoint, whereas 3-year EWL, morbidity, mortality, remission of obesity related comorbidities, quality of life (QOL) and hormonal and lipid profile changes are secondary endpoints. Eighty patients, 18 years or older and with a body mass index (BMI) between 35 and 50 kg/m2 who meet the Swiss guidelines for the surgical treatment of morbid obesity will be randomized. The endpoints and baseline measurements will be assessed pre-surgery, peri-surgery and post-surgery (fixed follow up measurements are at discharge and at the time points 6 weeks and 12 and 36 months postoperatively). DISCUSSION: With its 3-year follow up time, this RCT will provide important data on the impact of LMGB and LRYGB on EWL, remission of comorbidities, QOL and hormonal and lipid profile changes. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02601092 . Registered on 28 September 2015.

Residents' performance in open versus laparoscopic bench-model cholecystectomy in a hands-on surgical course.

INTRODUCTION: Laparoscopy has become the gold standard for many abdominal procedures. Among young surgeons, experience in laparoscopic surgery increasingly outweighs experience in open surgery. This study was conducted to compare residents' performance in laparoscopic versus open bench-model task. METHODS: In an international surgical skills course, we compared trainees' performance in open versus laparoscopic cholecystectomy in a cadaveric animal bench-model. Both exercises were evaluated by board-certified surgeons using an 8-item checklist and by the trainees themselves. RESULTS: 238 trainees with a median surgical experience of 24 months (interquartile range 14-48) took part. Twenty-two percent of the trainees had no previous laparoscopic and 62% no previous open cholecystectomy experience. Significant differences were found in the overall score (median difference of 1 (95% CI: 1, 1), p < 0.001), gallbladder perforation rate (73% vs. 29%, p < 0.001), safe dissection of the Calot's triangle (98% vs. 90%, p = 0.001) and duration of surgery (42 (13) minutes vs. 26 (10) minutes (mean differences 17.22 (95% CI: 15.37, 19.07), p < 0.001)), all favouring open surgery. The perforation rate in open and laparoscopic cholecystectomies was not consistently decreasing with increasing years of experience or number of previously performed procedures. Self-assessment was lower than the assessment by board-certified surgeons. CONCLUSION: Despite lower experience in open compared to laparoscopic cholecystectomy, better performance was observed in open task. It may be explained by a wider access with easier preparation. Open cholecystectomy is the rescue manoeuvre and therefore, it is important to provide also enough training opportunities in open surgery.