Cholecystostomy as an Exclusive Access to Remove Cystic, Common Hepatic, and Common Bile Duct Stones.

OBJECTIVE. The purpose of this article was to evaluate the feasibility and efficacy of percutaneous fluoroscopic-guided stone retrieval from the cystic duct and antegrade common bile duct (CBD) stone advancement into the duodenum exclusively through a cholecystostomy tube. MATERIALS AND METHODS. Twenty-one patients with acute cholecystitis and choledocholithiasis or an impacted cystic duct stone who underwent percutaneous cholecystostomy tube placement were retrospectively enrolled in this study. The patients had a contra-indication for cholecystectomy (17 patients because of comorbidities and one who declined surgery) or had failed endoscopic retrograde stone removal attempts (three patients). RESULTS. The 21 patients underwent subsequent percutaneous CBD (17 patients) and cystic duct (nine patients) stone removal on follow-up sessions through the percutaneous cholecystostomy track using moderate sedation. A total of 32 stone removal procedures were performed. Seventeen patients underwent balloon dilatation sphincterotomy, after which the CBD stones were pushed forward into the duodenum using a compliant balloon. Seven patients also had stone removal from the cystic duct by a stone retrieval basket. The primary technical success rate for removal of all CBD and cystic duct stones was 76%. The secondary technical success rate was 100%. The clinical success rate was 74%. All patients tolerated the procedures well without major complication. The clinical follow-up interval ranged from 2 to 2310 days (median, 30 days), with no incidence of postprocedural complications. CONCLUSION. Percutaneous transcholecystic common bile and cystic duct stone removal through an existing cholecystostomy access is a safe and effective procedure that is well tolerated.

Coloration affects heating and cooling in three color morphs of the Australian bluetongue lizard, Tiliqua scincoides.

The color-mediated thermoregulation hypothesis predicts that dark body color (low reflectance) allows organisms to gain heat more efficiently than does pale coloration (high reflectance). This prediction is intuitive and widely assumed to be true, but has poor empirical support. We used rare, captive-bred, mutant melanistic, albino and wild-type Australian bluetongue lizards, Tiliqua scincoides to measure the effects of skin reflectance on the heating and cooling rates. We measured heating under an artificial radiant heat source and cooling rates in an ice-cooled box using live lizards in a room with still air. The effect of skin reflectance on heat transfer was clear, despite the substantial influence of body size. Melanistic T. scincoides showed low reflectance and gained heat faster than highly reflective albinos. Melanistic lizards also lost heat faster than albinos. Wild-type lizards were intermediate in reflectance, gained heat at rates indistinguishable from melanistic lizards, and lost heat at rates indistinguishable from albino lizards. This study system allowed us to control for variables that were confounded in other studies and may explain the inconsistent support for the color-mediated thermoregulation hypothesis. Our results provide clear evidence that skin reflectance influences the rate of heating and cooling in ectotherms.

Squamate scavenging services: Heath goannas (Varanus rosenbergi) support carcass removal and may suppress agriculturally damaging blowflies.

Human-induced environmental change has caused widespread loss of species that support important functions for ecosystems and society. For example, vertebrate scavengers contribute to the functional health of ecosystems and provide services to agricultural landscapes by removing carcasses and associated pests. Widespread extirpation of native Australian mammals since the arrival of Europeans in Australia has removed many scavenging species from landscapes, while scavenging mammals such as European red foxes (Vulpes vulpes) have been introduced. In much of Australia, squamate reptiles are the largest native terrestrial scavengers remaining, where large native mammals are extinct and conservation management is being undertaken to remove invasive mammals. The contribution of reptiles to scavenging functions is not well understood. In this study, we investigated the ecosystem functions provided by large reptiles as scavengers to better understand how populations can be managed to support ecosystem services. We investigated the ecosystem services provided by vertebrate scavengers in Australian coastal mallee ecosystems, focusing on the heath goanna (Varanus rosenbergi), the only extant native terrestrial scavenger in the region. We carried out exclosure experiments, isolating the scavenging activity of different taxonomic groups to quantify the contribution of different taxa to scavenging services, specifically the removal of rat carcasses, and its impact on the occurrence of agriculturally damaging blowflies. We compared areas with different native and invasive scavenger communities to investigate the impact of invasive species removal and native species abundance on scavenging services. Our results indicated that vertebrate scavenging significantly contributes to carcass removal and limitation of necrophagous fly breeding in carcasses and that levels of removal are higher in areas associated with high densities of heath goannas and low densities of invasive mammals. Therefore, augmentation of heath goanna populations represents a promising management strategy to restore and maximize scavenging ecosystem services.

Image-guided tunneled peritoneal dialysis catheter placement.

Patients with end-stage renal disease (ESRD) often will ultimately require dialysis to survive. One type of dialysis is peritoneal dialysis (PD), which utilizes the vessel-rich peritoneum as a semi-permeable membrane to filter blood. In order to perform PD, a tunneled catheter must be placed through the abdominal wall and into the peritoneal space, with ideal positioning of the catheter within the most dependent portion of the pelvis, represented by the rectouterine or rectovesical space in women and men, respectively. There are several approaches to PD catheter insertion, including open surgical, laparoscopic surgical, blind percutaneous, and image-guided with the use of fluoroscopy techniques. Interventional radiology (through the use of image-guided percutaneous techniques) is an infrequently utilized resource to place PD catheters, and offers real-time imaging confirmation of catheter positioning with similar outcomes to more invasive surgical catheter insertion approaches. Although the vast majority of dialysis patients receive hemodialysis instead of peritoneal dialysis in the United States, some countries have moved towards a "Peritoneal Dialysis First" initiative, prioritizing initial PD, as it is less burdensome on healthcare facilities as it can be performed at home. In addition, the outbreak of the COVID-19 pandemic has produced shortages of medical supplies and delays in care delivery worldwide, while simultaneously generating a shift away from in-person medical visits and appointments. This shift may be met with more frequent utilization of imaged-guided PD catheter placement, reserving surgical and laparoscopic placement for complex patients who may require omental periprocedural revisions. This literature review outlines a brief history of PD, the various techniques of PD catheter insertion, patient selection criteria, and new COVID-19 considerations, in anticipation for the increased demand for PD in the United States.

Gastroduodenal artery pseudoaneurysm and chronic superior mesenteric vein thrombosis treated with transcatheter embolization and stent dilatation, respectively: 7 year clinical and imaging follow-up.

Pancreatic pseudocyst formation, arterial pseudoaneurysm, and splanchnic vein thrombosis are complications of chronic pancreatitis that account for significant morbidity and mortality in this patient population. While the short-term utility of timely endovascular intervention for treating the vascular complications of chronic pancreatitis have been relatively well documented, there is a paucity of longitudinal follow-up in this patient population, therefore making it difficult to predict the long-term efficacy of these interventions. This report details a case of a gastroduodenal artery pseudoaneurysm embolization followed by symptomatic superior mesenteric vein chronic thrombosis treated by stent dilatation in a patient with chronic pancreatitis, with 7 years clinical and imaging follow-up.

CT-guided percutaneous bilateral sacroiliac joint arthroplasty.

Pelvic fractures and sacroiliac joint (SI) diastasis are debilitating injuries which can drastically decrease an individual's functional capacity, and lead to significant morbidity and mortality. In younger, healthier populations, pelvic fractures are usually the result of sudden traumatic forces, such as a motor vehicle collision. Atraumatic pelvic fractures can also occur, and are most commonly due to age related changes and osteoporosis. Even with prompt surgical management, pelvic fractures often result in a host of challenging complications such as disruption of the SI joint with subsequent limitations in mobility and chronic pain. In this case report, we present a novel treatment of SI diastasis, secondary to corticosteroid induced osteoporosis and pelvic fractures. We performed percutaneous bilateral poly-methyl-methacrylate (PMMA) SI joint fusions under CT-guidance. Here we describe a case of bilateral SI joint CT guided percutaneous arthroplasty for osteoporotic SI joint diastasis and pelvic fractures, resulting in a rapid resolution of SI joint pain and restoration of the ability to ambulate in a previously wheelchair-bound patient. This may be of particular benefit in patients who are poor surgical candidates who experience osteoporotic fractures and would be otherwise unable to receive definitive operative management of their pathologic fractures.

Iatrogenic abdominal aortic pseudoaneurysm repaired by percutaneous image-guided translumbar embolization.

Aortic injury is a frequently encountered condition that can present as a life-threatening emergency. When this injury occurs in the retroperitoneal portion of the aorta, it can be difficult to diagnose and treat because of the location. Although surgical repair remains the mainstay of treatment, surgery might not be an option for some patients. We have presented a case of a 54-year-old nonoperative candidate who had experienced iatrogenic retroperitoneal abdominal aortic rupture with pseudoaneurysm formation. The patient was successfully treated with the novel use of a proven technique: direct percutaneous embolization of the pseudoaneurysm sac via a translumbar approach under image guidance.

Limited Utility of Gadolinium Contrast Administration in Routine Multiple Sclerosis Surveillance.

BACKGROUND AND PURPOSE: Assess the incidence of enhancing lesions on follow-up MRIs in patients with multiple sclerosis (MS) to determine the utility of intravenous, gadolinium-based contrast agent (IV-GBCA) use in routine follow-up imaging. METHODS: We retrospectively identified head MRIs associated with an MS diagnosis acquired between January 1, 2015and January 10, 2018. Final reports were reviewed to determine the presence of (1) a new or larger lesion, (2) at least one enhancing lesion, and (3) if at least one enhancing lesion was new or larger on Fluid-Attenuation Inversion Recovery (FLAIR). For MRIs with at least one enhancing lesion, but no new or larger enhancing lesions, reports and images of the preceding MRI were reviewed. RESULTS: A total of 1,805 MRIs performed on 920 patients were included. 354/1,805 (20%) MRIs reported new or enlarging lesions. 138/1,805 (8%) MRIs reported at least one enhancing lesion. Of these, 117/138 (85%) reported at least one enhancing lesion that was new or larger. In the remaining 21 MRIs which contained an enhancing lesion but none of the enhancing lesions were reported as new or enlarging, at least one enhancing lesion was present on preceding MRI. CONCLUSIONS: Enhancing lesions are uncommon on follow-up MRIs in MS patients. Our data suggest that new enhancing lesions are not present on a follow-up MRI when two conditions are met: (1) preceding MRI does not demonstrate any enhancing lesions and (2) there is no interval change of the lesions on the current 3D-T2-FLAIR sequence compared to the preceding 3D-T2-FLAIR sequence. IV-GBCA should be reserved for instances when temporal knowledge of lesion formation is needed.

Diaphragm Morphology Assessed by Computed Tomography in Chronic Obstructive Pulmonary Disease.

Rationale: Chronic obstructive pulmonary disease (COPD) is associated with abnormal skeletal muscle morphology and function. Objectives: To test the hypothesis that in vivo diaphragm muscle morphology assessed by computed tomography (CT) imaging would be associated with COPD severity, exacerbations, health status, and exercise capacity. Methods: The COPD Morphometry Study is a cross-sectional study that enrolled a clinical sample of smokers with COPD. Spirometry was performed and COPD severity was defined according to guidelines. Three-dimensional left hemidiaphragm morphology was segmented from contiguous axial CT images acquired at maximal inspiration, yielding quantitative measures of diaphragm CT density in Hounsfield units, dome height, and muscle volume. Exacerbations prompting pharmacotherapy or hospitalization in the preceding 12 months and St. George's Respiratory Questionnaire for COPD were assessed. Incremental symptom-limited cycle ergometry quantified peak oxygen uptake ([Formula: see text]o2Peak). Associations were adjusted for age, sex, body height, body mass index, and smoking status. Results: Among 65 smokers with COPD (75% male; [mean ± standard deviation (SD)] 56 ± 26 pack-years; forced expiratory volume in 1 second [FEV1] percentage predicted 55 ± 23%), mean diaphragm CT density was 3.1 ± 10 Hounsfield units, dome height was 5.2 ± 1.3 cm, and muscle volume was 57 ± 24 cm3. A 1-SD decrement in the diaphragm CT density was associated with 8.3% lower FEV1, 3.27-fold higher odds of exacerbation history, 9.7-point higher score on the St. George's Respiratory Questionnaire for COPD, and 2.5 ml/kg/min lower [Formula: see text]o2Peak. A 1-SD decrement in dome height was associated with 11% lower FEV1 and 1.3 ml/kg/min lower [Formula: see text]o2Peak. There were no associations with diaphragm volume observed. Conclusions: CT-assessed diaphragm morphology was associated with COPD severity, exacerbations, impaired health status, and exercise intolerance. The mechanisms and functional impact of lower diaphragm CT density merit investigation.

Erratum: Uncomplicated percutaneous IVC filter removal following implantation time of 6033 days.

[This corrects the article DOI: 10.1016/j.radcr.2020.05.008.].

Uncomplicated percutaneous IVC filter removal following implantation time of 6033 days.

Pulmonary embolism (PE) is a major cause of morbidity and mortality in the United States and usually occurs secondary to venous thromboembolism. Inferior vena cava (IVC) filters are minimally invasive intravascular devices placed in patients who are at increased risk for venous thromboembolism leading to PE, however, has a contraindication to medical anticoagulation therapy. The longest reported case of a retrievable IVC filter has remained in place and successfully removed in a living patient has been 4753 days (13 years). We present a case of an uneventful, successful IVC removal with a dwell time of 6033 days (16 years).

Urinary Bladder Matrix Reinforcement for Laparoscopic Hiatal Hernia Repair.

BACKGROUND AND OBJECTIVES: Synthetic mesh reinforcement during laparoscopic hiatal hernia repair (LHHR) reduces recurrence. Biologically derived mesh is also associated with reduced recurrence. Urinary bladder matrix (UBM), a biologically derived extracellular matrix mesh, has shown clinical success. We wanted to determine the safety and efficacy of LHHR with porcine UBM reinforcement. METHODS: This retrospective, single-surgeon study reviewed clinical data on patients who underwent LHHR from August 2009 through May 2014, with diaphragmatic reinforcement with porcine UBM mesh. Primary outcomes were (1) recurrence-a >2-cm defect above the diaphragm at 3 months; (2) intra- and postoperative complications; (3) pre- and postoperative esophageal reflux (GERD) or dysphagia; and (4) cessation of proton pump inhibitor (PPI). RESULTS: Sixty-two patients who had LHHR with UBM mesh were studied (mean age, 62 years, 53 women, mean body mass index 32.7 kg/m2) Before surgery 98% had GERD, 19% had dysphagia, and 98% were on PPI. Postoperative UGIS was performed on 66% 3 months after surgery, and 19% had a recurrence of >2 cm; 56% remained on PPI, and 16% (P < .001) remained symptomatic. Dysphagia improved in 75% (P = .05). No intraoperative complications were recorded. One postoperative mortality occurred secondary to an unrelated cardiac event. CONCLUSIONS: UBM mesh was effective and safe for LHHR. In addition to reducing the rate of recurrence compared to unreinforced primary repair, the properties of UBM, including site-specific constructive tissue remodeling, may add benefits over other biologic products. This study represents an evaluation of UBM mesh in a large cohort of patients who underwent LHHR.

Group living in squamate reptiles: a review of evidence for stable aggregations.

How sociality evolves and is maintained remains a key question in evolutionary biology. Most studies to date have focused on insects, birds, and mammals but data from a wider range of taxonomic groups are essential to identify general patterns and processes. The extent of social behaviour among squamate reptiles is under-appreciated, yet they are a promising group for further studies. Living in aggregations is posited as an important step in the evolution of more complex sociality. We review data on aggregations among squamates and find evidence for some form of aggregations in 94 species across 22 families. Of these, 18 species across 7 families exhibited 'stable' aggregations that entail overlapping home ranges and stable membership in long-term (years) or seasonal aggregations. Phylogenetic analysis suggests that stable aggregations have evolved multiple times in squamates. We: (i) identify significant gaps in our understanding; (ii) outline key traits which should be the focus of future research; and (iii) outline the potential for utilising reproductive skew theory to provide insights into squamate sociality.

Tumor size predicts long-term survival in colon cancer: an analysis of the National Cancer Data Base.

BACKGROUND: American Joint Committee on Cancer uses tumor size for "T" staging of many solid tumors for its effect on prognosis. However, tumor size has not been incorporated in tumor (T), nodal status (N), metastasis (M) staging for colon cancer. Hence, the National Cancer Data Base was used to determine whether tumor size correlates with TNM staging and survival. METHODS: For the 300,386 patients, tumor size was divided into S1 (0 to 2 cm), S2 (>2 to 4 cm), S3 (>4 to 6 cm), and S4 (>6 cm). Statistical comparison was done for TNM stage, grade, and nodal status with tumor size. Kaplan-Meier survival analysis was done for each "S" stage. RESULTS: Of the 300,386 patients, 13% were classified as S1, 39% S2, 30% S3 and 18% as S4. Right colon was the most common site (48%). Tumor size positively correlated with grade, T stage, and nodal stage. Tumor size was inversely associated with survival. CONCLUSION: Tumor size is positively correlated with important prognostic factors and negatively impacted survival.

The prognostic value of additional malignant lesions detected by magnetic resonance imaging versus mammography.

BACKGROUND: Nodal positivity is correlated with a poorer prognosis in breast cancer. A study was composed to compare nodal positivity in patients with single versus multiple lesions found on magnetic resonance imaging (MRI) and mammogram (MMG). METHODS: A retrospective study of breast cancer patients undergoing MRI and MMG was performed. Nodal positivity was compared in patients with additional invasive lesions found on MRI versus single invasive lesions found on MRI and MMG. RESULTS: A total of 425 patients were included. The overall nodal positivity was 23.8%. Patients with single versus multiple malignant lesions had nodal positivity of 20.9% vs 31.1% (P = .04). MRI detected multiple lesions in 120 patients, 80 of which were not detected by MMG (18.8%). Comparing single lesions with additional malignant lesions detected by MRI only, nodal positivity increased from 20.9% to 51.6% (P = .0002). CONCLUSIONS: Patients with additional invasive lesions on MRI had significantly higher nodal positivity than single invasive lesions. Hence, addition of MRI in early-stage breast cancer may have prognostic value because of detection of potential node-positive patients.

Evolution of color variation in dragon lizards: quantitative tests of the role of crypsis and local adaptation.

Many animal species display striking color differences with respect to geographic location, sex, and body region. Traditional adaptive explanations for such complex patterns invoke an interaction between selection for conspicuous signals and natural selection for crypsis. Although there is now a substantial body of evidence supporting the role of sexual selection for signaling functions, quantitative studies of crypsis remain comparatively rare. Here, we combine objective measures of coloration with information on predator visual sensitivities to study the role of crypsis in the evolution of color variation in an Australian lizard species complex (Ctenophorus decresii). We apply a model that allows us to quantify crypsis in terms of the visual contrast of the lizards against their natural backgrounds, as perceived by potential avian predators. We then use these quantitative estimates of crypsis to answer the following questions. Are there significant differences in crypsis/conspicuousness among populations? Are there significant differences in crypsis conspicuousness between the sexes? Are body regions "exposed" to visual predators more cryptic than "hidden" body regions? Is there evidence for local adaptation with respect to crypsis against different substrates? In general, our results confirmed that there are real differences in crypsis/conspicuousness both between populations and between sexes; that exposed body regions were significantly more cryptic than hidden ones, particularly in females; and that females, but not males, are more cryptic against their own local background than against the background of other populations [corrected]. Body regions that varied most in contrast between the sexes and between populations were also most conspicuous and are emphasized by males during social and sexual signaling. However, results varied with respect to the aspect of coloration studied. Results based on chromatic contrast ("hue" of color) provided better support for the crypsis hypothesis than did results based on achromatic contrast ("brightness" of color). Taken together, these results support the view that crypsis plays a substantial role in the evolution of color variation and that color patterns represent a balance between the need for conspicuousness for signaling and the need for crypsis to avoid predation.

Aberrant drainage of sentinel lymph nodes in colon cancer and its impact on staging and extent of operation.

BACKGROUND: The role of aberrant lymphatic drainage in changing operations for patients undergoing sentinel lymph node mapping in colon cancer has not been described on a large scale. METHODS: Patients with colon cancer underwent sentinel lymph node mapping and standard oncologic resection. Aberrant lymphatic drainage was identified outside the standard resection margin, requiring change of the extent of operation. Objectives were to identify the frequency of aberrant lymphatic drainage leading to changes of operation and staging. RESULTS: Among 192 patients undergoing standard oncologic resection, 42 (22%) had extended surgery because of aberrant lymphatic drainage. Nodal positivity was higher in patients undergoing change of operation, at 62% compared with 43% of those undergoing only standard oncologic resection. In 19 of 192 patients (10%), positive sentinel nodes were found in aberrant locations. CONCLUSIONS: Sentinel node mapping in patients with colon cancer detects aberrant drainage in 22% of patients, changing the extent of operation.

Vibrational signaling in the agonistic interactions of red-eyed treefrogs.

Sensitivity to substrate-borne vibrations is widespread in animals and evolutionarily precedes hearing but, compared with other sensory modalities, we know little about vibrational communication, particularly in vertebrates. For plant-dwelling arthropods, vibrations are likely as important as sound. Arboreal vertebrates excite plant vibrations with most movements, but the behavioral relevance of these vibrations has not been tested experimentally. In playback experiments using a robotic model frog and an electrodynamic shaker, we demonstrate that plant-borne vibrations generated by the shaking (tremulation) display of male red-eyed treefrogs (Agalychnis callidryas) are a vibrational signal, necessary and sufficient to elicit tremulations in response. A trend toward increased aggression during visual playbacks suggests that the visual component of tremulations may also convey information. In male-male contests, tremulations were the most frequent aggressive display, and their use and vibrational characteristics varied with male size and conflict context. Nearly all of A. callidryas' signaling behaviors, including tremulations and acoustic calls, excite strong, stereotyped vibrations that travel through plants and could be informative to receivers. Our results demonstrate that vibrational signals serve a key role in the biology of one well-known arboreal frog and suggest that consideration of the vibrational modality may significantly broaden our appreciation of the behavior and evolution of arboreal vertebrates.