Perianal Mucinous Adenocarcinoma Found Incidentally From Perianal Mass.

Anal mucinous adenocarcinomas are very rare and usually arise from anal fistulas. We report a case of a 73-year-old man with a past medical history of hypertension admitted to our facility for evaluation of bleeding from a large, tender, left gluteal perianal mass. The patient reported the mass had been growing for over six years. On examination, an ulcerated, fungating large exophytic lesion was found extending from the anal verge laterally engulfing the left gluteus. The patient was anemic with low hemoglobin and hematocrit, as well as an elevated carcinoembryonic antigen level. A colonoscopy was performed during which an internal opening of a left-sided anal fistula was identified. The mass was biopsied and returned positive for a mucinous adenocarcinoma. Staging imaging including a computed tomography scan of the chest abdomen and pelvis did not show any metastatic disease. A magnetic resonance image of the pelvis revealed a locally invasive, heterogeneous tumor extending from the perianal soft tissue to the posterior wall of the anal canal and lower rectum. The patient was discussed at the interdisciplinary tumor board and completed five weeks of concurrent chemotherapy and radiation with 5-fluorouracil and a total of 28 fractions of radiation. He then underwent abdominoperineal resection with a vertical rectus abdominis myocutaneous flap. The patient was placed in the surgical intensive care unit and subsequently discharged in stable condition on postoperative day 14. This case highlights the presentation, diagnosis, and management of anal mucinous adenocarcinoma.

Adult-onset perianal Langerhans cell histiocytosis presenting as pruritus ani: a case report and review of the literature.

BACKGROUND: Langerhans cells belong to the histiocytic system and give rise to two tumors: Langerhans cell histiocytosis and Langerhans cell sarcoma. Clinical aggressiveness and degree of atypia distinguish the two neoplasms. Langerhans cell histiocytosis can infiltrate a single or multiple organ systems and particularly affects bone, skin, and lymph nodes. Perianal cutaneous Langerhans cell histiocytosis is a rare condition in adults, with 15 cases reported in the literature. CASE: We present the case of a 50-year-old hispanic man who presented with a 9-month history of pruritus ani and a personal history of diabetes insipidus. Punch biopsy confirmed a lesion of Langerhans cells origin but could not exclude Langerhans cell sarcoma because of limited sample size. An additional biopsy was planned as well as a positron emission tomography scan to determine the extent of disease spread. While the patient failed to follow up for repeat biopsy, the positron emission tomography scan was performed and was negative for metastatic disease. A stable perianal lesion of Langerhans cell histiocytosis with benign clinical features in a 50-year-old male despite lack of treatment is extremely rare and has not been described in the literature so far. Here, we review the presentation and workup of patients with Langerhans cell histiocytosis, review the relevant literature, and discuss treatment planning. CONCLUSION: Perianal Langerhans cell histiocytosis is rare, and there should be a high index of suspicion with chronic or new perianal lesions, especially in a patient with a history of diabetes insipidus. It is also important to consider the patient's full clinical course when it is not possible to reach a definitive pathological diagnosis before management.

A model of workflow in the hospital during a pandemic to assist management.

We present a computational model of workflow in the hospital during a pandemic. The objective is to assist management in anticipating the load of each care unit, such as the ICU, or ordering supplies, such as personal protective equipment, but also to retrieve key parameters that measure the performance of the health system facing a new crisis. The model was fitted with good accuracy to France's data set that gives information on hospitalized patients and is provided online by the French government. The goal of this work is both practical in offering hospital management a tool to deal with the present crisis of COVID-19 and offering a conceptual illustration of the benefit of computational science during a pandemic.

A method for going from 2D laparoscope to 3D acquisition of surface landmarks by a novel computer vision approach.

PURPOSE: This paper presents a method to use the Smart Trocars-our new surgical instrument recognition system-or any accurate localization system of surgical instrument for acquiring intraoperative surface data. Complex laparoscopic surgeries need a proper guidance system which requires registering the preoperative data from a CT or MRI scan to the intraoperative patient state. The Smart Trocar can be used to localize the instruments when it comes to contact with the soft tissue surface. METHOD: Two successive views through the laparoscope at different angles with the 3D localization of a fixed tool at one single location using the Smart Trocars can point out visible features during the surgery and acquire their location in 3D to provide a depth map in the region of interest. In other words, our method transforms a standard laparoscope system into a system with three-dimensional registration capability. RESULT: This method was initially tested on a simulation for uncertainty assessment and then on a rigid model for verification with an accuracy within 2 mm distance. In addition, an in vivo experiment on pig model was also conducted to investigate how the method might be used during a physiologic respiratory cycle. CONCLUSION: This method can be applied in a large number of surgical applications as a guidance system on its own or in conjunction with other navigation techniques. Our work encourages further testing with realistic surgical applications in the near future.

Consensus-Derived Coronary Anastomotic Checklist Reveals Significant Variability Among Experts.

BACKGROUND: Surgical skill assessment tools frequently reflect the opinions of small groups of surgeons. That raises concerns over their generalizability as well as their utilization when applied broadly. A Delphi approach could engage a broad group of experts to identify key elements for a checklist assessing coronary anastomotic skill, improving generalizability. METHODS: Expert surgeons in North America (10 or more years in practice, actively teaching coronary artery surgery) were contacted randomly to participate. Consenting surgeons first provided items they believed were mandatory when performing a coronary artery bypass. These were then entered into a three-round Delphi. Positive consensus was reached when 75% or more of participants ranked an item mandatory. RESULTS: Sixteen faculty consented to participate. Each participant provided 25 ± 10 items. The 407 items provided were condensed, resulting in 146 items in the final list, divided into six sections based on the conduct of the operation. Twenty-three items reached consensus in the first round, 14 in the second, and 3 in the third. These 40 items represented only 27% of the initial 146 items. Agreement within sections varied widely, from 0% for "management of assistants" to 47% for "testing and final steps." CONCLUSIONS: A randomly selected group of experts using a Delphi approach can generate a checklist to assess construction of a coronary artery bypass. Considerable disagreement among experts regarding what steps are mandatory calls into question the generalizability of any locally developed checklist.

The SmartOR: a distributed sensor network to improve operating room efficiency.

BACKGROUND: Despite the significant expense of OR time, best practice achieves only 70% efficiency. Compounding this problem is a lack of real-time data. Most current OR utilization programs require manual data entry. Automated systems require installation and maintenance of expensive tracking hardware throughout the institution. This study developed an inexpensive, automated OR utilization system and analyzed data from multiple operating rooms. STUDY DESIGN: OR activity was deconstructed into four room states. A sensor network was then developed to automatically capture these states using only three sensors, a local wireless network, and a data capture computer. Two systems were then installed into two ORs, recordings captured 24/7. The SmartOR recorded the following events: any room activity, patient entry/exit time, anesthesia time, laparoscopy time, room turnover time, and time of preoperative patient identification by the surgeon. RESULTS: From November 2014 to December 2015, data on 1003 cases were collected. The mean turnover time was 36 min, and 38% of cases met the institutional goal of ≤30 min. Data analysis also identified outlier cases (>1 SD from mean) in the domains of time from patient entry into the OR to intubation (11% of cases) and time from extubation to patient exiting the OR (11% of cases). Time from surgeon identification of patient to scheduled procedure start time was 11 min (institution bylaws require 20 min before scheduled start time), yet OR teams required 22 min on average to bring a patient into the room after surgeon identification. CONCLUSION: The SmartOR automatically and reliably captures data on OR room state and, in real time, identifies outlier cases that may be examined closer to improve efficiency. As no manual entry is required, the data are indisputable and allow OR teams to maintain a patient-centric focus.

"Five on a Dice" Port Placement Allows for Successful Robot-Assisted Left Pneumonectomy.

Background Technology has evolved to facilitate pulmonary resection. The latest technological advances in computer-aided surgery (Da Vinci Xi) allow for more control during pulmonary resection. Case Description A 59-year-old woman presented with two primary tumors of the left upper and lower lung. After induction chemotherapy, patient had a "five on a dice" port placement and technique was used to perform successful robot-assisted pneumonectomy. The patient was discharged home on postoperative day 3 without any complications. Conclusions We have found that the "five on a dice" port placement allows for optimal control of the robot stapler and facilitates successful robot-assisted left pneumonectomy.

Image-guided simulation of tissue deformation using a mechanical model on a surgical application.

This paper presents a method for localizing the position of a liver and a tumor within the tissue during a minimally invasive liver operation. From pre-operative CT scans, the liver volume and its internal structures are segmented using image-processing techniques. Based on these segmentations, a three-dimensional mechanical model is built to compute the liver volume and internal structure displacement under boundary conditions such as external forces from the surgical instrument. This can help the surgeon understand the motion of internal structures when manipulating the liver. To validate our method, an experiment on a porcine liver explant was performed to assess the difference between actual tissue motion and the mechanical model.

Esophageal stent migration: Testing few hypothesis with a simplified mathematical model.

Esophageal stent placement has significantly improved the quality of life in patients with malignant as well as benign esophageal obstructing lesions. Despite its early success and rapid adoption, stent migration still occurs in as many as 30% of cases especially with fully covered stents. To date, few models of interaction between the stent and the esophageal wall have been published and these have only focused on the deployment of the stent or the static mechanical stress distribution of the stent material. To elucidate the mechanism behind esophageal stent migration we developed a simplified radially symmetric computational model of esophageal peristalsis and the stent. A thorough review of the literature on esophageal peristalsis was performed and pertinent data were implemented into the model. Similarly, mechanical properties of an existing esophageal stent were used for the stent model. A sensitivity analysis of the parameters of the model enabled identification of the key elements of stent design that influence the degree of stent migration including flares design, stent length as well as longitudinal and radial stiffness. A comparison of the model to the migration rate reported in clinical studies for various types of fully covered stents further verified our model, which can significantly contribute to the development of a more stable esophageal stent with lower rates of migration.

Case report of using curved tip electrothermal bipolar coagulation to improve hilar dissection in VATS lobectomy.

INTRODUCTION: Thoracoscopic lobectomy has gained a pivotal role in the resection of lung cancer. To facilitate the minimally invasive approach, new surgical devices have been developed to help improve the feasibility of performing complex cases. Recently, we adopted the use of a 5mm curved tip electrothermal bipolar sealing device. PRESENTATION OF CASE: We highlight two patients with different type of hilum during VATS lobectomy. First patient had a peripheral lung cancer with simple hilum while second patient had bronchiectasis with very complex hilum. In both cases, use of 5mm curved tip electrothermal bipolar sealing device helped in successful completion of video-assisted thoracoscopic lobectomy. DISCUSSION: In these two cases, we were able to take advantage of the 5mm curved tip electrothermal bipolar sealing device in completion of the hilar dissection. CONCLUSION: Curved tip electrothermal bipolar sealing device allows complete dissection of hilar structures more easily during a lobectomy for simple and complex hilum. Use of this device may lead to more efficient VATS lobectomy.

Endoscopic evaluation of gastric conduit perfusion in minimally invasive Ivor Lewis esophagectomy.

INTRODUCTION: Laser-assisted indocyanine green (ICG) fluorescent dye angiography has been used in esophageal reconstructive surgery where it has been shown to significantly decrease the anastomotic leak rate. Recent advances in technology have made this possible in minimally invasive esophagectomy. PRESENTATION OF CASE: We present a 69-year-old male with a cuT2N0M0 adenocarcinoma of the esophagus at the gastroesophageal junction who presented to our clinic after chemoradiation and underwent a minimally invasive Ivor Lewis esophagectomy. The perfusion of the gastric conduit was assessed intraoperatively using endoscopic ICG fluorescent imaging system. The anastomosis was created at the well-perfused site identified on the fluorescent imaging. The patient tolerated the procedure well, had an uneventful recovery going home on postoperative day 6 and tolerating a regular diet 2 weeks after the surgery. DISCUSSION: Combination of minimally invasive surgery and endoscopic evaluation of perfusion of gastric conduit provide improved outcomes for surgical treatment for patients with esophageal cancer. CONCLUSION: The gastric conduit during minimally invasive Ivor Lewis esophagectomy can be evaluated using endoscopic ICG fluorescent imaging.

Endoscopic management of Boerhaave's syndrome presenting with hematemesis.

Hematemesis is an uncommon yet challenging presentation of Boerhaave's syndrome. Here, we present minimally invasive management of an esophageal perforation with hematemesis using esophageal stenting in an elderly male with multiple comorbidities.

Retention of left ventricular assist device outflow grafts after transplantation.

BACKGROUND: New sternum-preserving techniques are increasingly being utilized for implantation of left ventricular assist devices (LVADs) in bridge-to-transplant patients. During device explantation for transplantation through median sternotomy, the outflow graft is divided where convenient, which generally results in retention of a significant blind limb of outflow graft attached to the descending thoracic or supraceliac aorta. Although the retained graft could be completely excised through a repeat thoracotomy, we decided to investigate the short- and long-term complications related to retained grafts and whether they outweigh the risk of additional surgery. METHODS: We reviewed the charts and computed tomography (CT) scans of 18 patients who underwent successful bridge to cardiac transplantation between January 2003 and August 2006, and in whom the initial LVAD implant was performed via a sternum-sparing procedure. In each case, a blind graft limb was retained at the time of device explantation. RESULTS: An LVAD was implanted either through a left sub-costal incision (6 patients) or through a left thoracotomy (12 patients). Patients were supported for an average of 113 days while awaiting transplantation (13 to 299 days). Four patients died of causes not directly related to the retained graft. Mean observation time of the remaining 14 patients was 53.6 months (21.6 to 76.9 months). There was no evidence of distal emboli, pseudoaneurysm or graft infection in any patient. CONCLUSIONS: The presence of a retained graft limb after LVAD removal for transplantation is associated with few complications. For patients in whom removal of the graft would require additional surgery, oversewing the graft and leaving it in place is a reasonable strategy.