Role of hepatic metastatic lesion size on inter-reader reproducibility of CT-based radiomics features.

OBJECTIVES: To evaluate the effect of hepatic metastatic lesion size on inter-reader reproducibility of CT-based 2D radiomics imaging features. METHODS: Computerized tomography (CT) scans of 59 liver metastases from 34 patients with colorectal cancer were evaluated. Image segmentation was performed manually by three readers blinded to each other's results. For each radiomics feature, we created two datasets by sorting measurements according to size, i.e., (i) from the smallest to the largest lesion and (ii) from the largest to the smallest lesion. The Lin concordance correlation coefficient (CCC) was employed to analyze the reproducibility of radiomics features. In particular, the CCC was computed as a function of a number of elements in the dataset, by gradually adding lesions from each sorted dataset. To evaluate the effect of lesion size, we analyzed the difference between these two functions thus assessing the contribution of small and large lesions into the reproducibility of radiomics features. RESULTS: Inter-reader reproducibility of CT-based 2D radiomics features assessed using Lin's CCC demonstrates tumor-size dependence. For example, the Lin CCC for GLCM contrast equals 0.88 (95% C.I. 0.84 to 0.92, p < 0.003) and could change by an additional + / - 0.06 depending on the presence of large or small lesions. CONCLUSIONS: Groups of "large" and "small" lesions show different inter-reader reproducibility. The inter-reader reproducibility from the mixed group consisting of "large" and "small" lesions depends on the lesion-size distribution and can vary widely. This finding could partially explain variability in reproducibility of radiomics features in the literature. KEY POINTS: • Groups of "large" and "small" lesions show different inter-reader reproducibility. • The inter-reader reproducibility from the mixed group consisting of "large" and "small" lesions depends on the lesion-size distribution.

Ultrasound Workflow in a Pandemic: Lessons Learned from COVID-19.

The 2019 novel coronavirus (COVID-19) pandemic has posed unique, sudden challenges to health care systems. This is true particularly in the context of ultrasound logistics given the risks of inherent prolonged close contact of patients with sonographers and equipment during sonographic image acquisition. We describe the adaptations and modifications in scheduling, workflow, and imaging protocols implemented in our radiology department ultrasound division (a large urban academic center). The hierarchy of controls to minimize exposures to occupational hazards to protect workers, outlined by The National Institute for Occupational Safety and Health (NIOSH) are listed from most effective to least effective: elimination, substitution, engineering controls, administrative controls, and PPE (personal protective equipment (PPE)). Most of the mitigation techniques used in the ultrasound department to reduce hazards to workers involved administrative controls and PPE. We reduced preventable risks by using sterile precautions, imaging triage, and strategically minimizing image acquisition times. These implementations provide a modifiable framework for rapid adaptation during the evolving COVID-19 pandemic, including resurgences of variant strains. This framework ensures a level of preparedness for possible future pandemics or other widespread emergencies.

Rectourethral fistula following SpaceOAR gel placement for prostate cancer radiotherapy: A rare complication.

After undergoing a SpaceOAR® gel placement prior to planned radiotherapy for Gleason 4 + 4 prostate cancer, a 70-year-old male experienced severe right buttock pain and urine passing from his rectum. A colonoscopy and follow-up pelvic MRI demonstrated a large rectourethral fistula. The fistula was treated surgically with a robot-assisted radical prostatectomy, primary rectal repair, omental flap and diverting loop ileostomy. Pathology demonstrated extensive treatment effect with no residual prostate cancer. This is the first case study of a rectourethral fistula attributable to SpaceOAR® gel placement.

Body mass index as an indicator of the likelihood of ultrasound visualization of the appendix in pregnant women with suspicion of appendicitis.

PURPOSE: To determine if clinical characteristics of pregnant women are associated with the likelihood of ultrasound (US) visualization of the appendix in cases where there is a clinical suspicion of appendicitis. MATERIALS AND METHODS: A retrospective study of 471 pregnant patients with suspicion of appendicitis from 2009 to 2018 were studied. Patients underwent sonography of the appendix as their initial imaging study. The association of body mass index (BMI) and gestational age with sonographic visualization of the appendix was analyzed using logistic regression. Cut-off values were determined for BMI to predict visualization of the appendix. RESULTS: The rate of visualization of the appendix on US was 16% (95% CI 12% to 19%). When stratified by trimester of pregnancy, rebound pain on compression US examination in the 1st trimester and BMI in the 2nd and 3rd trimesters were identified as predictors of US visualization. Applying BMI cut-off values rounded to the nearest whole number, 36, 30, and 26 in the 1st, 2nd, and 3rd trimesters, non-visualization rates would be reduced by 16% (95% CI 10% to 25%), 35% (95% CI 29% to 42%), and 67% (95% CI 58% to 74%). Using BMI index cut-off values would reduce the number of primary US examinations by 35% (95% CI 30% to 39%) and increase the rate of visualization by 6% (95% CI 0.02% to 12%, P = 0.04). CONCLUSION: Using BMI cut-off values for determining the efficaciousness of US visualization of the appendix in pregnant women with suspicion of appendicitis could significantly reduce the non-visualization rate.

Dual-energy CT evaluation of gastrointestinal bleeding.

Gastrointestinal bleeding is a common cause for hospital admissions and is an important cause of morbidity and mortality. Although endoscopy is accepted as the standard initial diagnostic modality for the evaluation of gastrointestinal bleeding, multiphasic computed tomography (CT) imaging has become an alternative diagnostic tool. Dual-energy CT with post-processing techniques may have additional advantages over single-energy computed tomography in evaluation of gastrointestinal bleeding. In this article, we discuss the role of dual-energy CT in the evaluation of gastrointestinal bleeding with potential advantages over conventional CT and limitations.

Esophagogastric Junction Distensibility on Functional Lumen Imaging Probe Topography Predicts Treatment Response in Achalasia-Anatomy Matters!

INTRODUCTION: To compare the utility of the distensibility index (DI) on functional lumen imaging probe (FLIP) topography to other esophagogastric junction (EGJ) metrics in assessing treatment response in achalasia in the context of esophageal anatomy. METHODS: We prospectively evaluated 79 patients (at ages 17-81 years; 47% female patients) with achalasia during follow-up after pneumatic dilation, Heller myotomy, or per-oral endoscopic myotomy with timed barium esophagram, high-resolution impedance manometry, and FLIP. Anatomic deformities were identified based on consensus expert opinion. Patients were classified based on anatomy and EGJ opening to determine the association with radiographic outcome and Eckardt score (ES). RESULTS: Twenty-seven patients (34.1%) had an anatomic deformity-10 pseudodiverticula at myotomy, 7 epiphrenic diverticula, 5 sigmoid, and 5 sinktrap. A 5-minute column area of >5 cm was best associated with an ES of >3, with a sensitivity of 84% (P = 0.0013). Area under the curve for EGJ metrics in association with retention was as follows: DI, 0.90; maximal EGJ diameter, 0.76; integrated relaxation pressure, 0.64; and basal esophagogastric junction pressure, 0.53. Only FLIP metrics were associated with retention given normal anatomy (DI 2.4 vs 5.2 mm/mm Hg and maximal EGJ diameter 13.1 vs 16.6 mm in patients with and without retention, respectively; P values < 0.0001 and 0.002). Using a DI cutoff of <2.8 as abnormal, 40 of 45 patients with retention (P = 0.0001) and 23 of 25 patients with an ES of >3 (P = 0.02) had a low DI and/or anatomic deformity. With normal anatomy, 21 of 22 patients with retention had a low or borderline low DI. DISCUSSION: The FLIP DI is most useful metric for assessing the effect of achalasia treatment on EGJ opening. However, abnormal anatomy is an important mediator of outcome and treatment success will be modulated by anatomic defects that impede bolus emptying.

Comparison of Tin Filter-Based Spectral Shaping CT and Low-Dose Protocol for Detection of Urinary Calculi.

OBJECTIVE: The purpose of this study was to assess the performance of tin filter-based spectral shaping CT compared with routine low-dose CT for detection of urolithiasis. MATERIALS AND METHODS: Unenhanced third-generation dual-source CT scans of 129 consecutively registered patients were retrospectively reviewed: 43 patients underwent CT for detection of renal stones with tin filtration (Sn150 kV); 43 patients underwent a routine low-dose CT protocol at 100 kV; and 43 patients underwent a routine CT protocol with automated tube potential selection (110-120 kV). Image quality was evaluated subjectively and objectively. Volume CT dose index (CTDIvol) and size-specific dose estimate (SSDE) were recorded. To prospectively compare the performances of the spectral shaping protocol (Sn150 kV) with the standard (120 kV) and routine low-dose (100 kV) protocols, a phantom (sheep kidneys) containing stones were also scanned with each protocol and evaluated by two radiologists. RESULTS: CT with tin filtration resulted in 28% and 66% reduction in CTDIvol compared with CT performed with routine low-dose and standard-dose protocols (p < 0.05). Accordingly, it also led to 24% and 55% reduction in SSDE compared with the low-dose and standard protocols (p < 0.05). Subjective image quality and signal-to-noise ratio were similar between the tin filtration and the routine low-dose groups (p > 0.05). The objective image noise was similar in the three groups (p > 0.05). The phantom study showed no difference in detection of renal stones between the three tube potential settings. CONCLUSION: Using spectral shaping with tin filtration can substantially reduce radiation dose compared with routine standard- and low-dose abdominal CT for urinary stone disease.

Using value-based analysis to influence outcomes in complex surgical systems.

BACKGROUND: Value-based analysis (VBA) is a management strategy used to determine changes in value (quality/cost) when a usual practice (UP) is replaced by a best practice (BP). Previously validated in clinical initiatives, its usefulness in complex systems is unknown. To answer this question, we used VBA to correct deficiencies in cardiac surgery at Memorial Healthcare System. STUDY DESIGN: Cardiac surgery is a complex surgical system that lends itself to VBA because outcomes metrics provided by the Society of Thoracic Surgeons provide an estimate of quality; cost is available from Centers for Medicare and Medicaid Services and other contemporary sources; the UP can be determined; and the best practice can be established. RESULTS: Analysis of the UP at Memorial Healthcare System revealed considerable deficiencies in selection of patients for surgery; the surgery itself, including choice of procedure and outcomes; after care; follow-up; and control of expenditures. To correct these deficiencies, each UP was replaced with a BP. Changes included replacement of most of the cardiac surgeons; conversion to an employed physician model; restructuring of a heart surgery unit; recruitment of cardiac anesthesiologists; introduction of an interactive educational program; eliminating unsafe practices; and reducing cost. CONCLUSIONS: There was a significant (p < 0.01) reduction in readmissions, complications, and mortality between 2009 and 2013. Memorial Healthcare System was only 1 of 17 (1.7%) database participants (n = 1,009) to achieve a Society of Thoracic Surgeons 3-star rating in all 3 measured categories. Despite substantial improvements in quality, the cost per case and the length of stay declined. These changes created a savings opportunity of $14 million, with actual savings of $10.4 million. These findings suggest that VBA can be a powerful tool to enhance value (quality/cost) in a complex surgical system.

Establishment of genetically diverse patient-derived xenografts of colorectal cancer.

Preclinical compounds tested in animal models often show limited efficacy when transitioned into human clinical trials. As a result, many patients are stratified into treatment regimens that have little impact on their disease. In order to create preclinical models that can more accurately predict tumor responses, we established patient-derived xenograft (PDX) models of colorectal cancer (CRC). Surgically resected tumor specimens from colorectal cancer patients were implanted subcutaneously into athymic nude mice. Following successful establishment, fourteen models underwent further evaluation to determine whether these models exhibit heterogeneity, both at the cellular and genetic level. Histological review revealed properties not found in CRC cell lines, most notably in overall architecture (predominantly columnar epithelium with evidence of gland formation) and the presence of mucin-producing cells. Custom CRC gene panels identified somatic driver mutations in each model, and therapeutic efficacy studies in tumor-bearing mice were designed to determine how models with known mutations respond to PI3K, mTOR, or MAPK inhibitors. Interestingly, MAPK pathway inhibition drove tumor responses across most models tested. Noteworthy, the MAPK inhibitor PD0325901 alone did not significantly mediate tumor response in the context of a KRAS(G12D) model, and improved tumor responses resulted when combined with mTOR inhibition. As a result, these genetically diverse models represent a valuable resource for preclinical efficacy and drug discovery studies.

Anastomotic leaks: technique and timing of detection.

BACKGROUND: Despite the proven benefits of laparoscopic colorectal surgery, the rate of anastomotic leaks has not changed. This study looks at the time of presentation of anastomotic leaks between laparoscopic and open colectomies. METHODS: Retrospective chart review was performed between July 2008 and 2012. Two groups were created, laparoscopic and open. The time of presentation of significant leaks requiring reoperation were compared between the groups by index colectomies. Statistical analysis is presented as paired t test and chi-square test (P < .05). RESULTS: From 1,424 segmental colectomies, the anastomotic leak rate between the two groups was not statically significant (P = .69). No difference in the time of leak detection was evident (P = .67). Mortality rate was equal between the groups. The overall complication rate of the entire cohort was statically significant (P ≤ .001). CONCLUSION: The timing of anastomotic leak detection does not differ between laparoscopy and open colorectal resections.

Can moral reasoning predict general surgery residents' clinical competence?

BACKGROUND: When selecting residents for residency programs, there has been little success using standard academic criteria to predict their clinical performance. However, numerous studies in the past have found linkages between the nonstandard variable moral reasoning as measured by the instrument Defining Issues Test (Version 2; DIT-2) and clinical decision making with higher levels of moral reasoning linked to better clinical performance. This study sought to determine whether this important linkage exists in surgery residents. METHODS: The DIT-2 was administered to 20 surgical residents to assess level of moral reasoning, and data were collected on all end-of-rotation evaluations of residents by faculty to measure resident clinical competence. Candidate rank list data were examined from the past 5 years to determine linkages between moral development as measured by the DIT-2 and clinical competence. Correlation analyses, univariate regression, and stepwise multivariate regression were carried out to assess the relationships of moral reasoning as measured by the DIT-2 with other study variables. RESULTS: Analysis of data indicates a low correlation between DIT-2 scores and clinical competence. Rank list order showed a slight correlation with resident DIT-2 scores. Rank position was weakly correlated with individual competencies and aggregated scores for all competencies as measured by faculty evaluations. Rank position coupled with DIT-2 scores were predictive of 4 of the 6 ACGME competencies and predictive of clinical competence as measured by aggregated scores for all competencies. CONCLUSIONS: No linkages emerged between DIT-2 scores and clinical competence. This reasons for this may include the size of the population studied and the assumption that end-of-rotation evaluations measure resident clinical competence. There were significant relationships demonstrated when DIT-2 scores were linked with resident ranking. Future research should be continued in this area but with more rigorous instrumentation to measure clinical performance and a larger sample size.

Minimally invasive colorectal resection is associated with a transient increase in plasma hepatocyte growth factor levels early after surgery for colon cancer.

INTRODUCTION: Surgery's impact on blood levels of hepatocyte growth factor (HGF), a potent angiogenic factor, is unknown. Preoperative (PreOp) HGF blood levels are elevated in patients with colorectal cancer (CRC) and correlate with disease stage and prognosis. This study's purpose was to determine plasma HGF levels after minimally invasive colorectal resection (MICR) in patients with CRC. METHODS: Clinical and operative data were collected. Blood samples were obtained in all patients PreOp and on postoperative day (POD) 1 and 3; in some, samples were taken during weeks 2 and 3 after MICR. Late samples were bundled into 7-day time blocks. HGF levels were determined via enzyme-linked immunosorbent assay in duplicate. Student's t test was used to analyze the data (significance, P < .0125 after Bonferroni correction). RESULTS: A total of 28 CRC patients who underwent MICR were studied. Most had right, sigmoid, or left segmental colectomy. The mean plasma HGF level was higher on POD 1 (2417 ± 1476 pg/mL, P < .001) and POD 3 (2081 ± 1048 pg/mL, P < .001) when compared with PreOp levels (1045 ± 406 pg/mL). Plasma levels were back to baseline by the second (1100 ± 474 pg/mL, P = .64) and third postoperative weeks (1010 ± 327 pg/mL, P = .51). CONCLUSION: MICR for CRC is associated with a 1.9- to 2.3-fold increase in plasma HGF levels during the first 3 PODs after which levels normalize. This transient increase may briefly promote angiogenesis and the growth of residual tumor cells.

Minimally invasive colorectal resection for cancer is associated with a short-lived decrease in soluble Tie-2 receptor levels, which may transiently inhibit VEGF-mediated angiogenesis (via altered blood levels of free Ang-1 and Ang-2).

BACKGROUND: Angiopoetin- (Ang-) 1 inhibits and Ang-2 promotes VEGF-mediated angiogenesis via binding to endothelial cell-bound Tie-2 receptor (Tie-2). After minimally invasive colorectal resection (MICR), Ang-1 levels decrease and Ang-2 levels increase, which may stimulate angiogenesis in wounds and residual tumor foci. Soluble Tie-2 (sTie-2) modulates the effects of free Ang-1 and Ang-2 by binding to them. This study assessed perioperative MICR plasma sTie-2 levels. METHODS: Blood samples were taken preoperatively (PreOp) and on postoperative days (POD) 1 and 3 from 50 cancer and 53 benign disease MICR patients. In a subgroup, a fourth sample was taken between POD7 and POD13 and bundled as a single time point. sTie-2 levels (ng/ml) were determined via ELISA. The mean and SD were determined at each time point. The t test used for analysis. RESULTS: PreOp plasma sTie-2 levels were significantly higher in the benign group (27.6 ± 10.2) than in the cancer group (22.9 ± 7.9). A significant drop from PreOp occurred in sTie-2 levels in the cancer group on POD1 (20.0 ± 7.4) and POD3 (21.0 ± 6.6) and in the benign group on POD1 (24.8 ± 9.1). The benign group's POD3 and the cancer group's POD7-13 sTie-2 levels were statistically similar to the PreOp levels while the benign group's POD7-13 level was significantly higher. CONCLUSION: PreOp sTie-2 levels were significantly lower in cancer patients. MICR is associated with a significant short-lived decrease in plasma sTie-2 levels in cancer patients on POD1 and 3, which may briefly inhibit VEGF-mediated angiogenesis. The benign group's early results were similar.

Patterns of injury in geriatric falls.

Falls are the most common cause of trauma in the elderly. Data regarding patterns of injury following geriatric falls are scant. We conducted a retrospective review of falls in patients aged 65 years and older seen at a trauma center over a nine year period. Two thousand eighty three patients met the inclusion criteria. Hip fracture proved to be the dominant injury (55%), 98% of which were isolated. Five hundred seven (21%) were non-hip fractures. Two hundred thirty eight patients (10%) sustained traumatic intracranial hemorrhage. Chest injury was the next most common injury type (6.7%) with rib fractures comprising 86% of this subgroup. A pattern of association between intracranial hemorrhage and cervical spine fractures was identified. Intra-abdominal injuries are rare.

A comparison of laparoscopic, hand-assist and open sigmoid resection in the treatment of diverticular disease.

BACKGROUND: Laparoscopic colorectal surgery (LAP) has become more prevalent as evidence of its safety and benefits become apparent. However, in difficult cases, hand-assisted instrumentation has facilitated LAP. We examined the impact of hand-assisted laparoscopic surgery (HALS) on the treatment of sigmoid diverticular disease. METHODS: This is a retrospective study using a prospectively maintained database from January 1, 2000 through November 30, 2005. Patients were divided into 3 groups: open (n = 110), LAP (n = 17), and HALS (n = 98). Data include operative time, length of stay, surgical method, conversion rate, and reasons for conversion. RESULTS: Surgeries started as LAP were completed in that fashion 59% of the time, with 23% being converted to open and 18% converted to HALS (total 41%). HALS cases showed a 6% conversion rate to open surgery (OS). Duration of surgery and length of stay were similar between LAP and HALS. CONCLUSIONS: HALS should be considered the optimal approach for surgery for diverticular disease.

Local excision of stratified T1 rectal cancer.

BACKGROUND: Local excision has been accepted therapy for T1 rectal cancers. A recent study demonstrated that primary tumors with deeper submucosal invasion were associated with a higher rate of lymph node metastases than those with shallow invasion. Our aim was to determine the effect of the depth of submucosal penetration on recurrence and mortality rates following transrectal excision of T1 tumors. METHODS: This was a 34-year retrospective review of patients who had transrectal excision with clear margins for T1 rectal cancer. Tumors were stratified into submucosal (SM) levels, and recurrence and mortality rates were determined. RESULTS: Of 101 patients with T1 rectal cancer undergoing local excision, 31 had a full-thickness transrectal excision. Eight (26%) of the 31 patients developed a local recurrence, 2 of whom had both a local and distant recurrence. Four patients (13%) died from metastatic rectal cancer. CONCLUSIONS: The recurrence rate for transrectal excision of T1 rectal cancer is high. It may be beneficial for patients with early rectal cancer to have postoperative chemoradiation therapy or a more radical surgical procedure.

Colonoscopy in the office setting is safe, and financially sound ... for now.

PURPOSE: In 2000, the Centers for Medicare & Medicaid Services announced a plan to allow for enhanced reimbursement for office endoscopy. This change in reimbursement was phased in during three years. The purpose of this study was to evaluate the fiscal outcomes and quality measures in the first two and a one-half years of performing endoscopy in an office setting under the new Centers for Medicare & Medicaid Services guidelines. METHODS: The following financial parameters were gathered: number of endoscopies, expenses (divided into salaries and operational), net revenue, and margin for endoscopies performed in the office compared with the hospital. All endoscopies were performed by endoscopists with advanced training (gastroenterology fellowship or colon and rectal surgery residency). Monitoring equipment included continuous SaO2 and automated blood pressure in all patients and continuous electrocardiographic monitors in selected patients. Quality/safety data have been tracked in a prospective manner and include number of transfers to the hospital, perforations, bleeding requiring transfusion or hospitalization, and cardiorespiratory arrest. RESULTS: The financial outcomes are as follows: 13,285 endoscopies performed from the opening of the unit through December 2003; net revenue per case $504 per case; expense per case has dropped from $205 per case to $145 per case; the overall financial benefit of performing endoscopy in the office compared with the hospital was an additional $28 to $143 per case depending on the insurance carrier. The quality outcomes since inception of the unit include the following: 13,285 endoscopies; 0 hospital transfers, 0 cardiorespiratory arrests; 0 perforations; and 1 bleeding episode that required hospitalization. CONCLUSIONS: Endoscopy performed in the office setting is safe when done with appropriate monitoring and in the proper patient population. At the time of this study, office endoscopy also is financially rewarding but changes in Centers for Medicare & Medicaid Services reimbursement threaten the ability to retain any financial benefit.

Practice parameters for the surgical treatment of ulcerative colitis.

The American Society of Colon and Rectal Surgeons is dedicated to assuring high-quality patient care by advancing the science, prevention, and management of disorders and diseases of the colon, rectum, and anus. The Standards Committee is composed of Society members who are chosen because they have demonstrated expertise in the specialty of colon and rectal surgery. This committee was created to lead international efforts in defining quality care for conditions related to the colon, rectum, and anus. This is accompanied by developing Clinical Practice Guidelines based on the best available evidence. These guidelines are inclusive, and not prescriptive. Their purpose is to provide information on which decisions can be made, rather than dictate a specific form of treatment. These guidelines are intended for the use of all practitioners, health care workers, and patients who desire information about the management of the conditions addressed by the topics covered in these guidelines. It should be recognized that these guidelines should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all of the circumstances presented by the individual patient.