Human brain tissue identification using coherent anti-Stokes Raman scattering spectroscopy and diffuse reflectance spectroscopy for deep brain stimulation surgery.

Significance: We assess the feasibility of using diffuse reflectance spectroscopy (DRS) and coherent anti-Stokes Raman scattering spectroscopy (CARS) as optical tools for human brain tissue identification during deep brain stimulation (DBS) lead insertion, thereby providing a promising avenue for additional real-time neurosurgical guidance. Aim: We developed a system that can acquire CARS and DRS spectra during the DBS surgery procedure to identify the tissue composition along the lead trajectory. Approach: DRS and CARS spectra were acquired using a custom-built optical probe integrated in a commercial DBS lead. The lead was inserted to target three specific regions in each of the brain hemispheres of a human cadaver. Spectra were acquired during the lead insertion at constant position increments. Spectra were analyzed to classify each spectrum as being from white matter (WM) or gray matter (GM). The results were compared with tissue classification performed on histological brain sections. Results: DRS and CARS spectra obtained using the optical probe can identify WM and GM during DBS lead insertion. The tissue composition along the trajectory toward a specific target is unique and can be differentiated by the optical probe. Moreover, the results obtained with principal component analysis suggest that DRS might be able to detect the presence of blood due to the strong optical absorption of hemoglobin. Conclusions: It is possible to use optical measurements from the DBS lead during surgery to identify WM and GM and possibly the presence of blood in human brain tissue. The proposed optical tool could inform the surgeon during the lead placement if the lead has reached the target as planned. Our tool could eventually replace microelectrode recordings, which would streamline the process and reduce surgery time. Further developments are required to fully integrate these tools into standard clinical procedures.

Smoking status predicts anastomotic leak after esophagectomy: a systematic review & meta-analysis.

BACKGROUND: Anastomotic leak after esophagectomy is a major contributor to surgery-related morbidity and mortality. The purpose of this systematic review was to evaluate if positive-smoking status is associated with the incidence of this complication. METHODS: A systematic search of MEDLINE, EMBASE, Scopus, Web of Science and Cochrane Library was performed on April 4th, 2023. Inclusion criteria comprised human participants undergoing esophagectomy, age ≥ 18, n ≥ 5, and identification of smoking status. The primary outcome was incidence of anastomotic leak. Sub-group analysis by ex- or current smoking status was performed. Meta-analysis was performed with RevMan 5.4.1 using a Mantel-Haenszel random-effects model. Publication bias was evaluated visually with funnel plots and through the Egger test. RESULTS: A total of 220 abstracts were screened, of which 69 full-text studies were assessed for eligibility, with 13 studies selected for final inclusion. This included 16,103 patients, of which 4433 were ex- or current smokers, and 9141 were never smokers. Meta-analysis revealed an increased odds of anastomotic leak in patients with a positive-smoking status (current or ex-smokers) compared to never smokers (OR 1.44, 95% CI 1.18-1.76, I2 = 44%, p < 0.001. Meta-analysis of six studies comparing active smokers alone to never smokers identified a significant increased odds of anastomotic leak (OR 1.80, 95% CI 1.25-2.59, p = 0.002, I2 = 0%). Meta-analysis of five studies comparing ex-smokers to never smokers identified a significant increased odds of anastomotic leak (OR 1.36, 95% CI 1.02-1.82, p = 0.04, I2 = 0%). The odds of anastomotic leak decreased among ex-smokers compared to active smokers. CONCLUSION: The findings of this systematic review and meta-analysis support the association between positive-smoking status and the risk of anastomotic leak after esophagectomy. Results further emphasize the importance of preoperative smoking cessation to reduce post-operative morbidity.

Changes in Sarcopenia Status Predict Survival Among Patients with Resectable Esophageal Cancer.

BACKGROUND: Sarcopenia is a predictor of survival in patients with esophageal cancer. The objective of this research was to obtain insight into how changes in sarcopenia influence survival in resectable esophageal cancer. PATIENTS AND METHODS: A retrospective cohort of patients with esophageal cancer undergoing tri-modality therapy was selected. Body composition parameters from the staging, post-neoadjuvant, and 1-year surveillance computed tomography (CT) scans were calculated. Overall survival (OS) and disease-free survival (DFS) were evaluated using the Kaplan-Meier method and log-rank test, as well as multivariable Cox-proportional hazards models. RESULTS: Of 141 patients, 118 had images at all three timepoints. The median DFS and OS were 33.2 [95% confidence interval (CI) 19.1-73.7] and 34.5 (95% CI 23.1-57.6) months, respectively. Sarcopenia classified by the staging CT was present in 20 (17.0%) patients. This changed to 45 (38.1%) patients by the post-neoadjuvant scan, and 44 (37.3%) by the surveillance scan. In multivariable analysis, sarcopenia at the post-neoadjuvant scan was significantly associated with OS [hazards ratio (HR) 2.65, 95% CI 1.59-4.40; p < 0.001] and DFS (HR 1.80, 95% CI 1.03-3.13; p = 0.038). The net change in skeletal muscle index was associated with OS (HR 0.93, 95% CI 0.90-0.97; p < 0.001) and DFS (HR 0.94, 95% CI 0.91-0.98; p = 0.001). CONCLUSIONS: Patients who develop sarcopenia as a consequence of skeletal muscle wasting during neoadjuvant therapy are at risk for worse DFS and OS. Patients who have a net loss of muscle over time may be at high risk for early disease recurrence.

Optimizing management for early-stage esophageal adenocarcinoma: longitudinal results from a multidisciplinary program.

BACKGROUND: The management of early-stage esophageal cancer is nuanced. A multidisciplinary approach may optimize management through selection of candidates for surgical or endoscopic therapies. The objective of this research was to examine long-term outcomes of patients with early-stage esophageal cancer who undergo treatment with endoscopic resection or surgery. METHODS: Data on patient demographics, co-morbidities, pathology results, OS and RFS were obtained for both the endoscopic resection group and esophagectomy group. Univariate analysis of OS and RFS were conducted using the Kaplan-Meier method with calculation of the log-rank test. Multivariate cox-proportional hazards models were created for OS and RFS using a hypothesis-driven approach. A multivariate logistic regression model was created to identify predictors of esophagectomy among patients undergoing initial endoscopic resection. RESULTS: A total of 111 patients were included. The median OS for the surgery group was 67.0 months compared to 74.0 months in the endoscopic resection group (log-rank p = 0.93). The median RFS for the surgery group was 109.4 months compared to 63.3 months in the endoscopic resection group (log-rank p = 0.0127). On multivariable analysis, patients undergoing endoscopic resection had significantly worse RFS (HR 2.55, 95% CI 1.09-6.00; p = 0.032), but equivalent OS (HR 1.03, 95% CI 0.46-2.32; p = 0.941), compared to patients undergoing esophagectomy. High-grade disease (OR 5.43, 95% CI 1.13-26.10; p = 0.035) and submucosal involvement (OR 7.75, 95% CI 1.90-31.40; p = 0.004) were identified as significant predictors of proceeding to esophagectomy. CONCLUSIONS: Through a multidisciplinary approach, patients with early-stage esophageal cancer achieve excellent RFS and OS. Submucosal involvement and high-grade disease place patients at increased risk for local disease recurrence; these patients may undergo endoscopic resection safely if treated with a multidisciplinary approach incorporating endoscopic surveillance and surgical consultation. Further risk-stratification models may enable better patient selection and optimization of long-term outcomes.

Heart valve surgery and the obesity paradox: A systematic review.

Obesity has been associated with increased incidence of comorbidities and shorter life expectancy, and it has generally been assumed that patients with obesity should have inferior outcomes after surgery. Previous literature has often demonstrated equivalent or even improved rates of mortality after cardiac surgery when compared to their lower-weight counterparts, coined the obesity paradox. Herein, we aim to review the literature investigating the impact of obesity on surgical valve interventions. PubMed and Embase were systematically searched for articles published from 1 January 2000 to 15 October 2021. A total of 1315 articles comparing differences in outcomes between patients of varying body mass index (BMI) undergoing valve interventions were reviewed and 25 were included in this study. Patients with higher BMI demonstrated equivalent or reduced rates of postoperative myocardial infarction, stroke, reoperation rates, acute kidney injury, dialysis and bleeding. Two studies identified increased rates of deep sternal wound infection in patients with higher BMI, although the majority of studies found no significant difference in deep sternal wound infection rates. The obesity paradox has described counterintuitive outcomes predominantly in coronary artery bypass grafting and transcatheter aortic valve replacement. Recent literature has identified similar trends in other heart valve interventions. While the obesity paradox has been well characterized, its causes are yet to be identified. Further study is essential in order to identify the causes of the obesity paradox so patients of all body sizes can receive optimal care.