Migration of vascular embolisation material from the intravascular space to surrounding interstitial tissues in arteriovenous malformations.

We present the case of a young man active duty in the military who initially presented with pelvic pain and fullness during sexual activity. Extensive workup showed a large pelvic arteriovenous malformation (AVM). He underwent over 10 interventional radiology procedures to embolise his AVM and suffered multiple postoperative complications resulting in exploratory laparotomies, bowel resections and ultimately a colostomy. Six years after his embolisation procedures, he was found on imaging to have gluteal fluid collections with metallic particles, presumed to be migrated Onyx from his angioembolisations as a result of non-target embolisation. Current literature does not document other instances of Onyx material migrating from an intravascular source to interstitial tissue.

Rapid tumor-labeling kinetics with a site-specific near-infrared anti-CEA nanobody in a patient-derived orthotopic xenograft mouse model of colon cancer.

BACKGROUND/OBJECTIVES: Nanobodies are the smallest biologic antigen-binding fragments derived from camelid-derived antibodies. Nanobodies effect a peak tumor signal within minutes of injection and present a novel opportunity for fluorescence-guided surgery (FGS). The present study demonstrates the efficacy of an anti-CEA nanobody conjugated to near-infrared fluorophore LICOR-IRDye800CW for rapid intraoperative tumor labeling of colon cancer. METHODS: LS174T human colon cancer cells or fragments of patient-derived colon cancer were implanted subcutaneously or orthotopically in nude mice. Anti-CEA nanobodies were conjugated with IRDye800CW and 1-3 nmol were injected intravenously. Mice were serially imaged over time. Peak fluorescence signal and tumor-to-background ratio (TBR) were recorded. RESULTS: Colon cancer tumors were detectable using fluorescent anti-CEA nanobody within 5 min of injection at all three doses. Maximal fluorescence intensity was observed within 15 min-3 h for all three doses with TBR values ranging from 1.3 to 2.3. In the patient-derived model of colon cancer, fluorescence was detectable with a TBR of 4.6 at 3 h. CONCLUSIONS: Fluorescent anti-CEA nanobodies rapidly and specifically labeled colon cancer in cell-line-based and patient-derived orthotopic xenograft (PDOX) models. The kinetics of nanobodies allow for same day administration and imaging. Anti-CEA-nb-800 is a promising and practical molecule for FGS of colon cancer.

3D-Printed Ostomy Flange Stabilizer.

BACKGROUND: One of the coauthors with tetraplegia (quadriplegia) and a colostomy invented an ostomy flange stabilizer to act as a temporary backplate and aid in pouch changes. DEVICE DEVELOPMENT: In an interactive design process, a 3D-printed ostomy flange stabilizer device was created. The resulting device can be adapted to 3 standard stoma appliance sizes. The stabilizer is reversible, allowing right- and left-handed people to use it on right- or left-sided stomas. Anyone with a 3D printer can print this device from an open-access Web site. CONCLUSION: This device may be of use to many with ostomies and especially those with impaired dexterity.A 3D-printed ostomy flange stabilizer is described. 3D printing allows patient inventions to be disseminated without commercialization.

Outcomes for a Large Cohort of Patients with Rectal Neuroendocrine Tumors: an Analysis of the National Cancer Database.

BACKGROUND: Rectal neuroendocrine tumors comprise 20% of neuroendocrine tumors in the alimentary tract, but there is controversy surrounding the optimal management of this disease. The purpose of this study is to better define treatment for patients with rectal neuroendocrine tumors. METHODS: Using the National Cancer Database, we analyzed patients with rectal neuroendocrine tumors between 2004 and 2015. Patients with metastatic disease and missing treatment data were excluded. We examined overall survival stratified by tumor size, treatment type, and presence of positive lymph nodes using Kaplan-Meier analysis with log-rank test. Cox proportional hazard regression model was performed to identify factors associated with overall survival. RESULTS: In total, 17,448 patients with rectal neuroendocrine tumors were identified; 16,531 of these patients met inclusion criteria. The majority of patients had tumors ≤ 10 mm (9216 patients, 79.8%), and approximately 90% underwent local excision. The probability of 5-year overall survival was significantly higher for patients with smaller tumors (≤ 10 mm: 94.1% 11-20 mm: 85.7%, > 20 mm: 71.8%; p < 0.001) and those with no positive lymph nodes (91.4% versus 53.3%, p < 0.001). The probability of 5-year overall survival differed based on treatment modality (local excision: 93.6%, radical resection: 79.1%, observation alone: 77.1%; p < 0.001). On multivariable Cox regression, when compared to local excision, radical resection was not associated with a difference in overall survival but observation alone was associated with significantly worse OS (HR = 2.750, p < 0.001). CONCLUSIONS: There is a significant difference in overall survival between patients who underwent local excision versus observation alone. Excision of the tumor should be offered to all patients with rectal neuroendocrine tumors who are appropriate surgical candidates, regardless of the tumor size.

Better characterization of operation for ulcerative colitis through the National surgical quality improvement program: A 2-year audit of NSQIP-IBD.

INTRODUCTION: There is little consensus of quality measurements for restorative proctocolectomy with ileal pouch-anal anastomosis(RPC-IPAA) performed for ulcerative colitis(UC). The National Surgical Quality Improvement Program(NSQIP) cannot accurately classify RPC-IPAA staged approaches. We formed an IBD-surgery registry that added IBD-specific variables to NSQIP to study these staged approaches in greater detail. METHODS: We queried our validated database of IBD surgeries across 11 sites in the US from March 2017 to March 2019, containing general NSQIP and IBD-specific perioperative variables. We classified cases into delayed versus immediate pouch construction and looked for independent predictors of pouch delay and postoperative Clavien-Dindo complication severity. RESULTS: 430 patients received index surgery or completed pouches. Among completed pouches, 46(28%) and 118(72%) were immediate and delayed pouches, respectively. Significant predictors for delayed pouch surgery included higher UC surgery volume(p = 0.01) and absence of colonic dysplasia(p = 0.04). Delayed pouch formation did not significantly predict complication severity. CONCLUSIONS: Our data allows improved classification of complex operations. Curating disease-specific variables allows for better analysis of predictors of delayed versus immediate pouch construction and postoperative complication severity. SHORT SUMMARY: We applied our previously validated novel NSIP-IBD database for classifying complex, multi-stage surgical approaches for UC to a degree that was not possible prior to our collaborative effort. From this, we describe predictive factors for delayed pouch formation in UC RPC-IPAA with the largest multicenter effort to date.

Local excision versus radical resection in patients with rectal neuroendocrine tumours: a propensity score match analysis.

BACKGROUND: The rectum is a common site for neuroendocrine tumours of the gastrointestinal tract. Diagnosis of these tumours has been increasing in recent years, highlighting the need to better define treatment options for patients with rectal neuroendocrine tumours (rNETs). METHODS: We performed a retrospective analysis using the National Cancer Database (2004-2014) to compare overall survival (OS) between local excision (LE) and radical resection (RR). To minimize bias, we performed three propensity score-matched comparisons stratified by tumour size: <10 mm, 10-20 mm, >20 mm. We compared OS by Kaplan-Meier analysis. We also examined margin status and postoperative outcomes for each comparison. RESULTS: A total of 12 996 patients underwent surgical treatment for rNET. There was no significant difference in probability of 10-year OS between LE and RR for patients with tumours <10 mm (88.6% versus 83.8%, P = 0.631, respectively) and tumours 10-20 mm (69.5% versus 69.3%, P = 0.226, respectively). In patients with tumours >20 mm, probability of 10-year OS was significantly longer in the LE group (76.5% versus 37.0%, P < 0.001). For all tumour sizes <10 mm and >20 mm, RR had significantly higher rates of 30-day readmission and negative margins. In subset analysis, there was no difference in OS for patients with positive margins after LE versus negative margins after RR for all tumour size groups. CONCLUSIONS: Our findings suggest that LE is a reasonable treatment option in patients with rNETs, especially for patients with high perioperative risk. Limitations to this study include its retrospective nature and inability to analyse surgeon decision-making.

Reliability of CT Angiography in Cerebral Vasospasm: A Systematic Review of the Literature and an Inter- and Intraobserver Study.

BACKGROUND AND PURPOSE: Computed tomography angiography offers a non-invasive alternative to DSA for the assessment of cerebral vasospasm following subarachnoid hemorrhage but there is limited evidence regarding its reliability. Our aim was to perform a systematic review (Part I) and to assess (Part II) the inter- and intraobserver reliability of CTA in the diagnosis of cerebral vasospasm. MATERIALS AND METHODS: In Part I, articles reporting the reliability of CTA up to May 2018 were systematically searched and evaluated. In Part II, 11 raters independently graded 17 arterial segments in each of 50 patients with SAH for the presence of vasospasm using a 4-category scale. Raters were additionally asked to judge the presence of any moderate/severe vasospasm (≥ 50% narrowing) and whether findings would justify augmentation of medical treatment or conventional angiography ± balloon angioplasty. Four raters took part in the intraobserver reliability study. RESULTS: In Part I, the systematic review revealed few studies with heterogeneous vasospasm definitions. In Part II, we found interrater reliability to be moderate at best (κ ≤ 0.6), even when results were stratified according to specialty and experience. Intrarater reliability was substantial (κ > 0.6) in 3/4 readers. In the per arterial segment analysis, substantial agreement was reached only for the middle cerebral arteries, and only when senior raters' judgments were dichotomized (presence or absence of ≥50% narrowing). Agreement on the medical or angiographic management of vasospasm based on CTA alone was less than substantial (κ ≤ 0.6). CONCLUSIONS: The diagnosis of vasospasm using CTA alone was not sufficiently repeatable among observers to support its general use to guide decisions in the clinical management of patients with SAH.

General surgery training in the era of robotic surgery: a qualitative analysis of perceptions from resident and attending surgeons.

BACKGROUND: The use of the surgical robot has increased annually since its introduction, especially in general surgery. Despite the tremendous increase in utilization, there are currently no validated curricula to train residents in robotic surgery, and the effects of robotic surgery on general surgery residency training are not well defined. In this study, we aim to explore the perceptions of resident and attending surgeons toward robotic surgery education in general surgery residency training. METHODS: We performed a qualitative thematic analysis of in-person, one-on-one, semi-structured interviews with general surgery residents and attending surgeons at a large academic health system. Convenient and purposeful sampling was performed in order to ensure diverse demographics, experiences, and opinions were represented. Data were analyzed continuously, and interviews were conducted until thematic saturation was reached, which occurred after 20 residents and seven attendings. RESULTS: All interviewees agreed that dual consoles are necessary to maximize the teaching potential of the robotic platform, and the importance of simulation and simulators in robotic surgery education is paramount. However, further work to ensure proper access to simulation resources for residents is necessary. While most recognize that bedside-assist skills are essential, most think its educational value plateaus quickly. Lastly, residents believe that earlier exposure to robotic surgery is necessary and that almost every case has a portion that is level-appropriate for residents to perform on the robot. CONCLUSIONS: As robotic surgery transitions from novelty to ubiquity, the importance of effective general surgery robotic surgery training during residency is paramount. Through in-depth interviews, this study provides examples of effective educational tools and techniques, highlights the importance of simulation, and explores opinions regarding the role of the resident in robotic surgery education. We hope the insights gained from this study can be used to develop and/or refine robotic surgery curricula.

Making the Jump: A Qualitative Analysis on the Transition From Bedside Assistant to Console Surgeon in Robotic Surgery Training.

OBJECTIVE: To determine barriers associated with the transition from bedside assistant to console surgeon for general surgery residents in the era of robotic surgery in general surgery training. DESIGN: Qualitative thematic analysis using one-on-one interviews of general surgery residents and attendings conducted between June 2018 and February 2019. SETTING: An urban, academic, multihospital general surgery residency program with a robust robotic surgery program. PARTICIPANTS: Convenient and purposeful sampling was performed to ensure a variety of resident graduate-years and attending subspecialties were represented. Sample size was determined by data saturation, which occurred after 20 resident and 7 attending interviews. RESULTS: Residents identified the low volume of general surgery robotic cases, the infrequency of exposure to robotic surgery, and attending comfort with robotic surgery (and with teaching on the robot) as potential barriers in the transition from bedside assistant to console surgeon. Residents had to find a replacement bedside assistant in order to be the console surgeon, which was challenging. In addition, residents felt that the current culture surrounding robotic surgery is very hierarchal, limiting their exposure. Attendings' trust in the residents' console skills was a major determining factor in allowing residents on the console. CONCLUSIONS: Most robotic surgery education curricula are sequential, requiring the resident to progress from bedside assistant to console surgeon. Unfortunately, there are many potential barriers for residents in the transition from bedside assistant to console surgeon. Some barriers apply to general surgery training overall, but are amplified in robotic surgery, while others are unique to robotic surgery education. Recognition of, and rectifying, these barriers may increase resident participation as the console surgeon.

Piles of Money: "Hemorrhoids" Are a Billion-Dollar Industry.

Two persistent problems confront anyone wishing to gauge the public-health cost and impact of hemorrhoids. First, there is the slipperiness of the term "hemorrhoids," which both patients and physicians use with imprecision. Second, there is endoscopic over-diagnosis of prominent anal cushions as internal hemorrhoids. While these factors both inflate the apparent cost of hemorrhoids, the fact remains that hemorrhoid diagnosis and treatment has become a billion-dollar industry.

Breaking the long-standing morphological paradigm: Individual prisms in the pearl oyster shell grow perpendicular to the c-axis of calcite.

Cross-sections of calcitic prismatic layers in mollusk shells, cut perpendicular to growth direction, reveal well-defined polygonal shapes of individual "grains" clearly visible by light and electron microscopy. For several kinds of shells, it was shown that the average number of edges in an individual prism approaches six during the growth process. Taking into account the rhombohedral symmetry of calcite, often presented in hexagonal axes, all this led to the long-standing opinion that calcitic prisms grow along the c-axis of calcite. In this paper, using X-ray diffraction and electron backscatter diffraction (EBSD), we unambiguously show that calcitic prisms in pearl oyster Pinctada margaritifera predominantly grow perpendicular to the c-axis. The obtained results imply that the hexagon-like habitus of growing crystallites may be not necessarily connected to calcite crystallography and, therefore, other factors should be taken into consideration. We analyze this phenomenon by comparing the organic contents in Pinctada margaritifera and Pinna nobilis shells, the later revealing regular growth of calcitic prisms along the c-axis.

Expectant Management of High-Grade Anal Dysplasia in People with HIV: Long-term Data.

BACKGROUND: Both ablation and expectant management of high-grade squamous intraepithelial lesions have been proposed. Expectant management would be reasonable if 1) the rate of high-grade squamous epithelial lesion progression to anal squamous cell carcinoma were low, and 2) anal squamous cell carcinoma arising under surveillance had a better prognosis than anal squamous cell carcinoma presenting without an identified precursor. OBJECTIVE: This study aims to quantify aspects of high-grade squamous epithelial lesion/anal squamous cell carcinoma clinical evolution in a surgical practice. DESIGN: This is a retrospective cohort study. SETTINGS: This study was performed in 1 colorectal surgeon's practice over a 20-year period. PATIENTS: Consecutive patients with high-grade squamous intraepithelial lesion and anal squamous cell carcinoma were included. MAIN OUTCOME MEASURES: We looked at the rate and timing of progression to anal squamous cell carcinoma, and the stage, treatment, and outcome of anal squamous cell carcinoma. We reviewed a comparison group of HIV-positive patients presenting de novo with anal squamous cell carcinoma (no prior history of high-grade squamous intraepithelial lesion). RESULTS: With consideration of only HIV-positive patients, 341 patients had a mean 5.6 years follow-up from high-grade squamous intraepithelial lesion diagnosis to the most recent documented anal examination. Twenty-four of these surveillance patients developed anal squamous cell carcinoma, yielding a progression rate of 1.3% per patient-year. Mean follow-up was 7.3 years from the initial cancer diagnosis to the most recent contact. Forty-seven patients who presented de novo with anal squamous cell carcinoma developed 74 lesions, with a mean follow-up of 5.7 years after initial diagnosis. This de novo group had higher anal squamous cell carcinoma-specific mortality (3% per patient-year vs 0.05%). Our study did not show a significantly higher rate of high stage (stage III or IV) at anal squamous cell carcinoma diagnosis in the de novo group in comparison with the surveillance group (25.5% vs 8.3% (p = 0.09)). LIMITATIONS: This study was retrospective in nature and had a predominately male population. CONCLUSIONS: The progression of untreated high-grade squamous intraepithelial lesion to anal squamous cell carcinoma approximates 1% per patient-year. Anal squamous cell carcinoma developing under surveillance tends to be of an earlier stage and to require fewer major interventions than anal squamous cell carcinoma presenting de novo. Cancer-specific mortality was lower for malignancies that developed under surveillance. We suggest that expectant management of patients with high-grade squamous intraepithelial lesion is a rational strategy for preventing anal cancer morbidity. See Video Abstract at http://links.lww.com/DCR/A699.

Twenty Years of a Veterans' Spinal Cord Injury Colorectal Clinic: Flexible Sigmoidoscopy and Multiple Hemorrhoid Ligation.

BACKGROUND: Colorectal and anal problems arise in chronic spinal cord injury care. We review 20 years of experience in a colorectal clinic at a veterans medical center treating mostly male veterans who have spinal cord injury. OBJECTIVE: We aim to show the results of colorectal interventions in a population with chronic spinal cord injury. DESIGN: This study is a retrospective records review. SETTINGS: This study was conducted at a Department of Veterans Affairs regional spinal cord injury center. PATIENTS: Six hundred forty-one individuals (625 males) made 1208 visits. Mean age was 56 ± 13 years; ages ranged from 21 to 90 years. INTERVENTIONS: Flexible sigmoidoscopy was done for diagnosis and screening, and hemorrhoid ligation was performed for symptomatic hemorrhoids. MAIN OUTCOME MEASURES: The primary outcomes measured were the frequency, timing, and results of procedures. RESULTS: Five hundred forty-eight people had 781 flexible sigmoidoscopies. At first examination, mean age was 65 ± 12 and the duration of injury was 19 ± 15 years. Sixty examinations (7.7%) displayed poor preparation. The interval between adequate-prepared examinations was 5.7 ± 2.0 years. The adenoma detection rate was 4.7%. Two hundred fifteen people had 406 hemorrhoid ligations. At first banding, the mean age was 52 ± 13 and the duration of injury was 20 ± 15 years. Mean number of ligations per procedure was 4.9 ± 2.0; a range of 1 to 20. Nine hemorrhoid operations were done in this period. Regarding the futility of procedures, 250 people died, with a mean age at death of 69 ± 11. The median time between any procedure and death was 4.4 years. Seventeen procedures were done within 6 months of death; these deaths were either unexpected or because of conditions identified at or after the procedure. LIMITATIONS: This was a retrospective review of a single institution, it involved a mostly male population, and it used a subjective assessment of bowel preparation. CONCLUSIONS: In a spinal cord injury colorectal clinic, sigmoidoscopy can keep screening current, with an acceptable level of poor preparation. The adenoma detection rate may or may not be adequate. Hemorrhoid ligation can be expanded beyond its limits in the non-spinal cord-injured population, including multiple and external banding, taking the place of an operation in most cases. These procedures are well tolerated and rarely futile.

Red coralline algae assessed as marine pH proxies using 11B MAS NMR.

Reconstructing pH from biogenic carbonates using boron isotopic compositions relies on the assumption that only borate, and no boric acid, is present. Red coralline algae are frequently used in palaeoenvironmental reconstruction due to their widespread distribution and regular banding frequency. Prior to undertaking pH reconstructions using red coralline algae we tested the boron composition of the red coralline alga Lithothamnion glaciale using high field NMR. In bulk analysed samples, thirty percent of boron was present as boric acid. We suggest that prior to reconstructing pH using coralline algae 1) species-specific boron compositions and 2) within-skeleton special distributions of boron are determined for multiple species. This will enable site selective boron analyses to be conducted validating coralline algae as palaeo-pH proxies based on boron isotopic compositions.