SF-TMN: SlowFast temporal modeling network for surgical phase recognition.

PURPOSE: Automatic surgical phase recognition is crucial for video-based assessment systems in surgical education. Utilizing temporal information is crucial for surgical phase recognition; hence, various recent approaches extract frame-level features to conduct full video temporal modeling. METHODS: For better temporal modeling, we propose SlowFast temporal modeling network (SF-TMN) for offline surgical phase recognition that can achieve not only frame-level full video temporal modeling but also segment-level full video temporal modeling. We employ a feature extraction network, pretrained on the target dataset, to extract features from video frames as the training data for SF-TMN. The Slow Path in SF-TMN utilizes all frame features for frame temporal modeling. The Fast Path in SF-TMN utilizes segment-level features summarized from frame features for segment temporal modeling. The proposed paradigm is flexible regarding the choice of temporal modeling networks. RESULTS: We explore MS-TCN and ASFormer as temporal modeling networks and experiment with multiple combination strategies for Slow and Fast Paths. We evaluate SF-TMN on Cholec80 and Cataract-101 surgical phase recognition tasks and demonstrate that SF-TMN can achieve state-of-the-art results on all considered metrics. SF-TMN with ASFormer backbone outperforms the state-of-the-art Swin BiGRU by approximately 1% in accuracy and 1.5% in recall on Cholec80. We also evaluate SF-TMN on action segmentation datasets including 50salads, GTEA, and Breakfast, and achieve state-of-the-art results. CONCLUSION: The improvement in the results shows that combining temporal information from both frame level and segment level by refining outputs with temporal refinement stages is beneficial for the temporal modeling of surgical phases.

CholecTriplet2021: A benchmark challenge for surgical action triplet recognition.

Context-aware decision support in the operating room can foster surgical safety and efficiency by leveraging real-time feedback from surgical workflow analysis. Most existing works recognize surgical activities at a coarse-grained level, such as phases, steps or events, leaving out fine-grained interaction details about the surgical activity; yet those are needed for more helpful AI assistance in the operating room. Recognizing surgical actions as triplets of combination delivers more comprehensive details about the activities taking place in surgical videos. This paper presents CholecTriplet2021: an endoscopic vision challenge organized at MICCAI 2021 for the recognition of surgical action triplets in laparoscopic videos. The challenge granted private access to the large-scale CholecT50 dataset, which is annotated with action triplet information. In this paper, we present the challenge setup and the assessment of the state-of-the-art deep learning methods proposed by the participants during the challenge. A total of 4 baseline methods from the challenge organizers and 19 new deep learning algorithms from the competing teams are presented to recognize surgical action triplets directly from surgical videos, achieving mean average precision (mAP) ranging from 4.2% to 38.1%. This study also analyzes the significance of the results obtained by the presented approaches, performs a thorough methodological comparison between them, in-depth result analysis, and proposes a novel ensemble method for enhanced recognition. Our analysis shows that surgical workflow analysis is not yet solved, and also highlights interesting directions for future research on fine-grained surgical activity recognition which is of utmost importance for the development of AI in surgery.

Non-Anastomotic Axillofemoral Bypass Disruption After Blunt Trauma Treated by Endovascular Approach.

Disruption in the non-anastomotic section of an axillofemoral bypass is a rare occurrence. In this report, we consider a patient who presented with a pseudoaneurysm in the non-anastomotic section of his axillofemoral bypass due to blunt trauma to the chest after a fall. Clinical presentation, management, treatment, and complications related to our case are discussed.

Surgical workflow recognition with temporal convolution and transformer for action segmentation.

PURPOSE: Automatic surgical workflow recognition enabled by computer vision algorithms plays a key role in enhancing the learning experience of surgeons. It also supports building context-aware systems that allow better surgical planning and decision making which may in turn improve outcomes. Utilizing temporal information is crucial for recognizing context; hence, various recent approaches use recurrent neural networks or transformers to recognize actions. METHODS: We design and implement a two-stage method for surgical workflow recognition. We utilize R(2+1)D for video clip modeling in the first stage. We propose Action Segmentation Temporal Convolutional Transformer (ASTCFormer) network for full video modeling in the second stage. ASTCFormer utilizes action segmentation transformers (ASFormers) and temporal convolutional networks (TCNs) to build a temporally aware surgical workflow recognition system. RESULTS: We compare the proposed ASTCFormer with recurrent neural networks, multi-stage TCN, and ASFormer approaches. The comparison is done on a dataset comprised of 207 robotic and laparoscopic cholecystectomy surgical videos annotated for 7 surgical phases. The proposed method outperforms the compared methods achieving a [Formula: see text] relative improvement in the average segmental F1-score over the state-of-the-art ASFormer method. Moreover, our proposed method achieves state-of-the-art results on the publicly available Cholec80 dataset. CONCLUSION: The improvement in the results when using the proposed method suggests that temporal context could be better captured when adding information from TCN to the ASFormer paradigm. This addition leads to better surgical workflow recognition.

Identifying Patient Characteristics Associated With Deficits in Surgical Decision Making.

BACKGROUND: Patient involvement in surgical decisions is formalized in the informed consent process, which should reflect that the patient understands their diagnosis, planned procedure, and the associated risks and benefits before consenting to treatment. If high-quality shared decision making has occurred, the treatment chosen should best match the goals and preferences of the patient. Little information currently exists that analyzes factors associated with decisional quality in surgery. Identifying patient factors correlated with specific deficits in preoperative decision making is essential for improvement of the shared decision-making process. This study aims to identify patient characteristics and coping strategies associated with the presence of knowledge deficits regarding their diagnosis and procedure so that interventions can be targeted to these vulnerable groups. METHODS: Approximately 882 preoperative patients were assessed regarding understanding of their diagnosis and procedure. Sociodemographic and decision-making variables were evaluated using validated measures. Univariate analysis and logistic regression models assessed factors associated with lower decisional quality. RESULTS: Approximately 136 (15%) of 882 patients had deficits in knowledge of diagnosis and/or procedure. Older patients were more likely to demonstrate these deficits (P = 0.0002). Using multivariate analysis, independent predictors of knowledge deficits included patients who identified themselves as Black, Asian, or other race (odds ratio [OR], 2.63; 95% confidence interval [CI], 1.19-5.85; and OR, 1.88; 95% CI, 1.00-3.55, respectively); were older (OR, 1.02; 95% CI, 1.01-1.04); and used denial as a coping strategy (OR, 2.61; 95% CI, 1.29-5.28). The use of acceptance as a coping strategy negatively predicted knowledge deficits (OR, 0.55; 95% CI, 0.36-0.84). CONCLUSIONS: Specific patient factors and coping strategies are associated with deficiencies in decisional quality. Identifying vulnerable groups at risk for these issues can help target methodologies and resources to ensure high-quality surgical decision making.

Mortality after emergency surgery continues to rise after discharge in the elderly: Predictors of 1-year mortality.

BACKGROUND: It is known that emergency surgery in the elderly is associated with high short-term mortality, but longer-term outcomes are not well described. We hypothesized that 30-day mortality may underestimate the true operative mortality experienced in this cohort. The purposes of this study were to characterize postoperative mortality rates extending to 1 year and to identify preoperative predictors of 1 year mortality after emergency abdominal surgery. METHODS: We retrospectively reviewed the records of all patients older than 70 years who underwent emergency abdominal surgery at a major teaching hospital between 2006 and 2011. Demographics, preoperative physiology, prehospital status, body mass index, laboratory values, Charlson scores, comorbid conditions, American Society of Anesthesiologists classification, and operative details were recorded. The primary end point was 1-year mortality. Complementary log-log binary regression was used to determine independent predictors of death. Model discrimination was evaluated using the c statistic. RESULTS: A total of 390 patients met our inclusion criteria. The mean age was 79 years, and 56% were women. Postoperative mortality was 16.2% at 30 days and 32.5% at 1 year, reflecting a doubling of mortality over 11 months. Independent preoperative predictors of 1-year mortality were Charlson score of 4 or higher (hazard ratio [HR], 1.79; 95% confidence interval [CI], 1.38-2.34), American Society of Anesthesiologists class of 4 or higher (HR, 1.66; 95% CI, 1.22-2.21), albumin less than 3.5 (HR, 1.71; 95% CI, 1.31-2.28), and body mass index lower than 18.5 (HR, 3.36; 95% CI, 1.48-6.86). The c statistic was 0.81. CONCLUSION: The 1-year mortality after emergency surgery in the elderly is significantly higher than that at 30 days. We identified a constellation of preoperative clinical markers that were highly predictive of this poor late outcome. The presence of these findings in the emergency setting should prompt preoperative discussion about treatment goals and encourage surgeons to set realistic expectations about outcomes with the patient and family. Future studies will develop a clinical scoring tool that can be applied at the bedside to provide more effective counseling for this high-risk population. LEVEL OF EVIDENCE: Epidemiologic/prognostic study, level III; therapeutic study, level IV.

Exercise protects against obesity induced semen abnormalities via downregulating stem cell factor, upregulating Ghrelin and normalizing oxidative stress.

Increased oxidative stress and hormonal imbalance have been hypothesized to underlie infertility in obese animals. However, recent evidence suggests that Ghrelin and Stem Cell Factor (SCF) play an important role in fertility, in lean individuals. Therefore, this study aimed at investigating whether changes in the levels of Ghrelin and SCF in rat testes underlie semen abnormal parameters observed in obese rats, and secondly, whether endurance exercise or Orlistat can protect against changes in Ghrelin, SCF, and/or semen parameters in diet induced obese rats. Obesity was modelled in male Wistar rats using High Fat Diet (HFD) 12-week protocol. Eight week-old rats (n=40) were divided into four groups, namely, Group I: fed with a standard diet (12 % of calories as fat); Group II: fed HFD (40 % of calories as fat); Group III: fed the HFD with a concomitant dose of Orlistat (200 mg/kg); and Group IV: fed the HFD and underwent 30 min daily swimming exercise. The model was validated by measuring the levels of testosterone, FSH, LH, estradiol, leptin, triglycerides, total, HDL, and LDL cholesterol, and final change in body weight. Levels were consistent with published obesity models (see Results). As predicted, the HFD group had a 76.8 % decrease in sperm count, 44.72 % decrease in sperm motility, as well as 47.09 % increase in abnormal sperm morphology. Unlike the control group, in the HFD group (i.e. obese rats) Ghrelin mRNA and protein were elevated, while SCF mRNA and protein were diminished in the testes. Furthermore, in the HFD group, SOD and GPx activities were significantly reduced, 48.5±5.8 % (P=0.0012) and 45.6±4.6 % (P=0.0019), respectively, while TBARS levels were significantly increased (112.7±8.9 %, P=0.0001). Finally, endurance exercise training and Orlistat administration individually and differentially protected semen parameters in obese rats. The mechanism includes, but is not limited to, normalizing the levels of Ghrelin, SCF, SOD, GPx and TBARS. In rat testes, diet induced obesity down regulates SCF expression, upregulates Ghrelin expression, and deteriorate oxidative stress levels, which are collectively detrimental to semen parameters. Exercise, and to a lesser extent Orlistat administration, protected effectively against this detrimental effect.

Superior mesenteric vein thrombosis after laparoscopic sleeve gastrectomy.

Laparoscopic procedures for morbid obesity are becoming standard of care which, in experienced hands, has a very low mortality and morbidity. Superior mesenteric vein thrombosis has been reported in the literature after different bariatric and nonbariatric laparoscopic procedures. Laparoscopic sleeve gastrectomy is a relatively new procedure in the treatment of morbid obesity; its complications being well-known including staple line leak, bleeding, and stricture among others. We present a case of superior mesenteric vein thrombosis after laparoscopic sleeve gastrectomy successfully managed conservatively with therapeutic anticoagulation, and propose a different hypothesis for the development of such a complication.

EVICEL glue-induced small bowel obstruction after laparoscopic gastric bypass.

Small bowel obstruction is a complication of laparoscopic Roux-en-Y gastric bypass (LRYGB) frequently caused by adhesions and internal hernia. In addition, anastomotic leak that complicates LRYGB surgery contributes to the mortality of this procedure. Fibrin glue is commonly used intraoperatively for prevention of anastomotic leak and to secure hemostasis. We describe 2 cases of morbidly obese women who underwent LRYGB surgery for weight loss and developed early postoperative small bowel obstruction related to the use of the "EVICEL" fibrin sealant. Of note is that both patients required surgical intervention for this complication.

Is weight loss better sustained with long-limb gastric bypass in the super-obese?

BACKGROUND: While some studies have shown that long-limb gastric bypass with Roux limb length of 150 to 200 cm can attain better weight loss outcomes in super-obese patients (BMI >50 kg/m(2)) than the standard limb gastric bypass with Roux limb length of 100 to 150 cm, other studies have not shown similar findings. Additionally, no study has demonstrated the optimal length of the Roux limb that will result in ideal weight loss. The purpose of this study is to compare the long-term weight loss and weight regain of standard limb length (SLL) and long limb length (LLL) gastric bypass in patients with BMI >50 kg/m(2). METHODS: A total of 120 patients with BMI >50 kg/m(2) underwent either SLL (total bypass length = 200, biliopancreatic limb = 50-80 cm, Roux limb = 120-150 cm) or LLL (total bypass length = 250 biliopancreatic limb = 50-80 cm, Roux limb = 170-200 cm) RYGB. The excess weight loss (EWL), the weight regain, and the rate of complications were measured at 1-, 2-, and 3-year follow-up. Statistical comparisons were performed using t-test. RESULTS: There was no difference in patient demographics, pre-operative BMI, or comorbidities between the two groups: SLL (n = 55) and LLL (n = 65). In comparing standard- to long-limb cohorts, preoperative BMI was 56.1 ±5.34 vs. 57.5 ± 6.05 kg/m(2), respectively. There was no statistical difference in percent EWL at 1, 2, and 3 years between the two groups [55.2 vs. 55 (P = 0.933), 61.5 vs. 60.8 (P = 0.831), and 61.1 vs.60 (P = 0.932)]. There was no difference in percent weight regain between the two groups, 11.2 (SLL) and 5.2 (LLL) (P = 0.13). The rates of complications were similar in the two groups. CONCLUSION: There is no difference in weight loss or weight regain between the SLL and LLL RYGB. Longer-limb gastric bypass is not required in patients with BMI >50 kg/m(2) for them to obtain long-term, sustained weight loss.

Breast cancer in women with human immunodeficiency virus infection: pathological, clinical, and prognostic implications.

BACKGROUND: AIDS and breast cancer have become two important public health issues for women. Of interest is the prolonged survival of patients diagnosed with HIV infection as a result of the use of highly active antiretroviral therapy (HAART). With improved survival, we are likely to see more HIV-infected patients with breast cancer. METHODS: This study, which is a review of our experience at Harlem Hospital Center, New York, between 2000 and 2008, compared HIV-positive with HIV-negative breast cancer patients, with attention to tumor size, stage, grade, molecular markers and lymphovascular invasion, treatment, and patient survival. RESULTS: Only 63 of 370 patients with breast carcinoma were tested for HIV, and 6 of the 63 women tested positive for HIV. We, therefore, compared the clinical features and tumor characteristics seen in the 6 HIV-infected women with those of the 57 HIV-seronegative breast cancer patients. We found no differences in presentation, median age, and tumor morphology in the two groups of patients. When the patients in our previous report on 5 HIV-positive breast cancer patients were added to the present group, the overall 5-year survival rate among the 11 HIV-infected patients was 75%. Of note is the finding that HIV infection in premenopausal women was not associated with aggressive breast cancer subtypes with poor survival outcome. CONCLUSIONS: These results demonstrate that histological subgroups and 5-year survival appear similar among HIV-positive breast cancer patients.

Novel technique for management of esophageal strictures: double "J" stents and the use of urologic dilators.

Current management of esophageal strictures using multiple dilations is the standard of care for symptomatic relief and cure. Diverse arrays of techniques have been developed with similar success rates. In this study we suggest the use of urologic dilator as a safe, alternative method for the management of esophageal strictures. We report a case of a patient with a history of severe, recurrent esophageal stricture secondary to tracheo-esophageal fistula repair, treated using Amplatz urologic dilators and double J stent as a mechanical temporizer for an esophageal stricture at risk for complete stenosis. Under general anesthesia, a flexible endoscope was passed into the proximal esophagus to visualize the stricture. A glide wire was passed through the stricture and its placement was confirmed by fluoroscopy. The endoscope was then removed and a series of urologic dilators sizing from 12Fr to 32Fr were passed through the stricture under fluoroscopic vision. Following this, a double "J" stent was left in place for further dilation sessions and to prevent complete stenosis. In conclusion, urologic dilators demonstrate a novel and simple technique for the treatment of esophageal strictures. This patient had no reported complications, and patient was able to tolerate the double "J" stent during dilation sessions.

Jejunal Bezoar causing obstruction after laparoscopic Roux-en-Y gastric bypass.

Bowel obstruction is a known complication of Roux-en-Y gastric bypass. It can be caused by adhesions, internal hernia, incarcerated ventral hernia, or intussusception. Sometimes the underlying cause may be unusual. These 2 case reports describe patients who underwent laparoscopic Roux-en-Y gastric bypass and whose postoperative courses were complicated by small-bowel obstruction due to phytobezoars in the ileum, distal to the jejunojejunal anastomosis. We reviewed the literature by using PubMed and Medline for causes, pathogenesis, classifications, diagnosis, and management.

Splenic injury after elective colonoscopy.

Splenic injury is a rare but serious complication of colonoscopy. Since the mid-1970s, 68 splenic injuries during colonoscopy including our 2 cases have been described. With the increasing use of colonoscopy, endoscopists, surgeons, and radiologists are more likely to encounter this unusual complication. Any cause of increased splenocolic adhesions, splenomegaly, or underlying splenic disease might be a predisposing factor for splenic injury during colonoscopy. However, it can occur in patients without significant adhesions or underlying splenic pathology. The diagnosis is often described in the literature as delayed, because many physicians are not aware of this complication of colonoscopy. Although computerized tomography is highly sensitive, knowledge of this complication is the best tool to aid in early diagnosis. Patients with abdominal pain, hypotension, and a drop in hematocrit without rectal bleeding after colonoscopy should be suspected of having splenic injury. Early recognition and interdisciplinary management are required to assure successful management of this potentially life-threatening injury. Patients with hemodynamic instability most often undergo surgery. We present 2 cases of splenic injury secondary to colonoscopy that required splenectomy.