Acute outcomes for the full US cohort of the FLASH mechanical thrombectomy registry in pulmonary embolism.

BACKGROUND: Evidence supporting interventional pulmonary embolism (PE) treatment is needed. AIMS: We aimed to evaluate the acute safety and effectiveness of mechanical thrombectomy for intermediate- and high-risk PE in a large real-world population. METHODS: FLASH is a multicentre, prospective registry enrolling up to 1,000 US and European PE patients treated with mechanical thrombectomy using the FlowTriever System. The primary safety endpoint is a major adverse event composite including device-related death and major bleeding at 48 hours, and intraprocedural adverse events. Acute mortality and 48-hour outcomes are reported. Multivariate regression analysed characteristics associated with pulmonary artery pressure and dyspnoea improvement. RESULTS: Among 800 patients in the full US cohort, 76.7% had intermediate-high risk PE, 7.9% had high-risk PE, and 32.1% had thrombolytic contraindications. Major adverse events occurred in 1.8% of patients. All-cause mortality was 0.3% at 48-hour follow-up and 0.8% at 30-day follow-up, with no device-related deaths. Immediate haemodynamic improvements included a 7.6 mmHg mean drop in mean pulmonary artery pressure (-23.0%; p<0.0001) and a 0.3 L/min/m2 mean increase in cardiac index (18.9%; p<0.0001) in patients with depressed baseline values. Most patients (62.6%) had no overnight intensive care unit stay post-procedure. At 48 hours, the echocardiographic right ventricle/left ventricle ratio decreased from 1.23±0.36 to 0.98±0.31 (p<0.0001 for paired values) and patients with severe dyspnoea decreased from 66.5% to 15.6% (p<0.0001).  Conclusions: Mechanical thrombectomy with the FlowTriever System demonstrates a favourable safety profile, improvements in haemodynamics and functional outcomes, and low 30-day mortality for intermediate- and high-risk PE.

Cellular morphological features are predictive markers of cancer cell state.

Even genetically identical cells have heterogeneous properties because of stochasticity in gene or protein expression. Single cell techniques that assay heterogeneous properties would be valuable for basic science and diseases like cancer, where accurate estimates of tumor properties is critical for accurate diagnosis and grading. Cell morphology is an emergent outcome of many cellular processes, potentially carrying information about cell properties at the single cell level. Here we study whether morphological parameters are sufficient for classification of single cells, using a set of 15 cell lines, representing three processes: (i) the transformation of normal cells using specific genetic mutations; (ii) metastasis in breast cancer and (iii) metastasis in osteosarcomas. Cellular morphology is defined as quantitative measures of the shape of the cell and the structure of the actin. We use a toolbox that calculates quantitative morphological parameters of cell images and apply it to hundreds of images of cells belonging to different cell lines. Using a combination of dimensional reduction and machine learning, we test whether these different processes have specific morphological signatures and whether single cells can be classified based on morphology alone. Using morphological parameters we could accurately classify cells as belonging to the correct class with high accuracy. Morphological signatures could distinguish between cells that were different only because of a different mutation on a parental line. Furthermore, both oncogenesis and metastasis appear to be characterized by stereotypical morphology changes. Thus, cellular morphology is a signature of cell phenotype, or state, at the single cell level.

Greenfield stainless steel vena cava filters on computed tomography follow-up.

OBJECTIVE: The objective of this study was to evaluate complications of Greenfield (Boston Scientific, Marlborough, Mass) stainless steel inferior vena cava (IVC) filters on follow-up computed tomography (CT) imaging and to elucidate associated risk factors. METHODS: Ninety-three patients with CT studies obtained for other reasons after Greenfield IVC filter placement (2007-2014) were retrospectively studied. Greenfield filters were placed permanently in those with venous thromboembolism and an expected lifelong contraindication to anticoagulation or life expectancy <6 months. Patients' demographic data, procedural characteristics, and imaging studies were reviewed and factors associated with perforation rates were analyzed. RESULTS: A total of 190 follow-up CT imaging studies were available for review. In total, filter-associated IVC thrombus (n = 10 [10.7%]) and pulmonary embolism breakthrough (n = 4 [4.3%)] were documented by contrast-enhanced CT. Perforation was evident in 18 patients (19.4%) with an average indwelling time of 256 days. No symptomatic perforation and no strut fracture were documented. There was no significant difference in perforation rate with respect to age of the patient (P = .61), sex (P = 1.00), or history of malignant disease (P = .40). The filter perforation rate and number of perforating struts were significantly higher in patients with longer indwelling time (>90 days) than in patients with shorter indwelling time (<90 days; P < .01). Caval cross-sectional areas of patients who experienced IVC filter perforations at >90 days were significantly smaller than those of nonperforated patients (284 vs 358 mm2; P < .01). CONCLUSIONS: Stainless steel Greenfield filters remain a relatively safe option for patients requiring permanent mechanical filtration.

TISMorph: A tool to quantify texture, irregularity and spreading of single cells.

A number of recent studies have shown that cell shape and cytoskeletal texture can be used as sensitive readouts of the physiological state of the cell. However, utilization of this information requires the development of quantitative measures that can describe relevant aspects of cell shape. In this paper we develop a toolbox, TISMorph, that calculates a set of quantitative measures to address this need. Some of the measures introduced here have been used previously, while others are new and have desirable properties for shape and texture quantification of cells. These measures, broadly classifiable into the categories of textural, irregularity and spreading measures, are tested by using them to discriminate between osteosarcoma cell lines treated with different cytoskeletal drugs. We find that even though specific classification tasks often rely on a few measures, these are not the same between all classification tasks, thus requiring the use of the entire suite of measures for classification and discrimination. We provide detailed descriptions of the measures, as well as the TISMorph package to implement them. Quantitative morphological measures that capture different aspects of cell morphology will help enhance large-scale image-based quantitative analysis, which is emerging as a new field of biological data.

Interventional Radiology-Operated Cholecystoscopy for the Management of Symptomatic Cholelithiasis: Approach, Technical Success, Safety, and Clinical Outcomes.

OBJECTIVE: The objective of our study was to report the technique, complications, and clinical outcomes of interventional radiology-operated cholecystoscopy with stone removal for the management of symptomatic cholelithiasis. MATERIALS AND METHODS: Ten (77%) men and three (23%) women (mean age, 65 years) with symptomatic cholelithiasis underwent cholecystostomy followed by interventional radiology-operated cholecystoscopy with stone removal. Major comorbidities precluding cholecystectomy included prior cardiac, pulmonary, or abdominal surgery; cirrhosis; sepsis with hyponatremia; seizure disorder; developmental delay; and cholecystoduodenal fistula. Cholecystostomy access, time between cholecystostomy and cholecystoscopy, endoscopic and fragmentation devices used, technical success, procedure time, fluoroscopy time, complications, length of hospital stay, time between cholecystoscopy and cholecystostomy removal, follow-up, and acute cholecystitis recurrence were recorded. RESULTS: Eleven (85%) patients underwent transhepatic cholecystostomy, and two (15%) patients underwent transperitoneal cholecystostomy. The mean time from cholecystostomy to cholecystoscopy was 151 days. Flexible endoscopy was used in eight (62%) patients, rigid endoscopy in three (23%), and both flexible and rigid in two (15%). Electrohydraulic lithotripsy was used in eight procedures, nitinol baskets in seven, ultrasonic lithotripsy in two, and percutaneous thrombectomy devices in one. Primary technical success was achieved in 11 (85%) patients, and secondary technical success was achieved in 13 (100%) patients. The mean procedure time was 164 minutes, and the mean number of procedures required to clear all gallstones was 1. One (8%) patient developed acute pancreatitis, and one (8%) patient died of gastrointestinal hemorrhage. The median hospital length of stay after cholecystoscopy was 1 day for postoperative monitoring. The mean time between cholecystoscopy and cholecystostomy removal was 39 days. One (8%) patient developed recurrent acute cholecystitis 1095 days after cholecystoscopy. CONCLUSION: Interventional radiology-operated cholecystoscopy may serve as an effective method for percutaneous gallstone removal in patients with multiple comorbidities precluding cholecystectomy.

Aortoenteric fistulae temporization and treatment: lessons learned from a multidisciplinary approach to 3 patients.

Aortoenteric fistulae are life-threatening conditions characterized by abnormal communications between the aorta and gastrointestinal tract. Aortoenteric fistulae may be characterized by the triad of bleeding, abdominal pain, or a pulsatile abdominal mass. Although hemorrhage is the most common presentation, it does not always occur; thus, patients may present with nonspecific symptoms. Computed tomography angiography findings suggestive of aortoenteric fistulae include ectopic gas within or adjacent to the aorta, discontinuity of the aortic wall, bowel wall thickening, and extravasation of contrast into the bowel. Endovascular treatments include retrograde balloon occlusion of the aorta and stent-graft deployment as well as coil, fibrin, and glue embolization of the fistulous tract. This report describes 3 cases of aortoenteric fistulae temporized and treated by interventional radiology and vascular and cardiac surgery at a single institution in an effort to increase awareness of this important clinical condition.

Role of inferior vena cava filters in transplant patients.

PURPOSE: This study evaluates the selection, use, and risks of permanent and retrievable inferior vena cava filters (IVCFs) in patients who have undergone organ transplantation. MATERIALS AND METHODS: Single-center retrospective review of 35 patients who had an IVCF placed following organ transplantation. Patient demographics, IVCF indication, and eligibility for retrieval were reviewed. Computed tomography (CT) studies showing the filter (n=22) were evaluated independently for IVCF adverse effects. RESULTS: Thirty-two (91%) of 35 patients had retrievable IVCFs placed while three (9%) patients received permanent IVCFs. Filter retrieval was indicated in three of the 32 patients receiving retrievable filters and was performed in two cases. Patients were ineligible for retrieval due to short life expectancy, complications/contraindications to anticoagulation, extended filter dwell time, lost to follow-up, and undetermined therapeutic value of anticoagulation. CONCLUSION: Current practices of filter placement usually dictate placing a retrievable IVCF in transplant patients. However, transplant patients are unlikely to be eligible for filter retrieval especially in situations of advanced age and comorbidities. Given the low incidence of eligibility for retrieval in this patient population, these results suggest preferential placement of permanent filters may reduce the potential morbidity due to filter-related complications, such as strut perforation, in transplant patients.

Measuring systematic changes in invasive cancer cell shape using Zernike moments.

We study the shape characteristics of osteosarcoma cancer cell lines on surfaces of differing hydrophobicity using Zernike moments to represent cell shape. We compare the shape characteristics of four invasive cell lines with a corresponding less-invasive parental line on three substrates. Cell shapes of each pair of cell lines are quite close and display overlapping characteristics. To quantitatively study shape changes in high-dimensional parameter space we project down to principal component space and define a vector that summarizes average shape differences. Using this vector we find that three of the four pairs of cell lines show similar changes in shape, while the fourth pair shows a very different pattern of changes. We find that shape differences are sufficient to enable a neural network to classify cells accurately as belonging to the highly invasive or the less invasive phenotype. The patterns of shape changes were also reproducible for repetitions of the experiment. We also find that shape changes on different substrates show similarities between the eight cells studied, but the differences were typically not enough to permit classification. Our paper strongly suggests that shape may provide a means to read out the phenotypic state of some cell types, and shape analysis can be usefully performed using a Zernike moment representation.

Changes in cell shape are correlated with metastatic potential in murine and human osteosarcomas.

Metastatic cancer cells for many cancers are known to have altered cytoskeletal properties, in particular to be more deformable and contractile. Consequently, shape characteristics of more metastatic cancer cells may be expected to have diverged from those of their parental cells. To examine this hypothesis we study shape characteristics of paired osteosarcoma cell lines, each consisting of a less metastatic parental line and a more metastatic line, derived from the former by in vivo selection. Two-dimensional images of four pairs of lines were processed. Statistical analysis of morphometric characteristics shows that shape characteristics of the metastatic cell line are partly overlapping and partly diverged from the parental line. Significantly, the shape changes fall into two categories, with three paired cell lines displaying a more mesenchymal-like morphology, while the fourth displaying a change towards a more rounded morphology. A neural network algorithm could distinguish between samples of the less metastatic cells from the more metastatic cells with near perfect accuracy. Thus, subtle changes in shape carry information about the genetic changes that lead to invasiveness and metastasis of osteosarcoma cancer cells.

Celect Inferior Vena Cava Wall Strut Perforation Begets Additional Strut Perforation.

PURPOSE: To identify risk factors for strut perforation following Celect inferior vena cava (IVC) filter (IVCF) placement and to use finite element modeling to predict the mechanical impact of long-dwelling filters. MATERIALS AND METHODS: Ninety-one patients with three computed tomography (CT) studies were evaluated following Celect IVCF placement (2007-2013). Three-dimensional finite element models of the Celect IVCF were developed to simulate mechanical deformation of the IVCF encountered in vivo. Simulated forces applied by the primary struts on the IVC wall were measured as a function of luminal area and tilt angle. RESULTS: Although 33 patients (36%) showed primary strut perforation on initial follow-up CT, 60 patients (66%) showed progressive perforation over time (P < .0001), with 72 patients (79%) showing primary strut perforation on the final CT (average, 554 d). Female patients (P = .004) and those with malignancy history (P = .01) had significantly higher perforation rates at a given time. Caval area also decreased after primary filter strut perforation, and we therefore proposed that this was the mechanism for progressive perforation. Consistent with this mechanism, three-dimensional finite element modeling demonstrated increasing strut force with decreasing IVC diameter. CONCLUSIONS: Celect IVCF primary strut perforation is progressive over time and is more common in female patients and those with a history of malignancy. In addition, this progressive perforation may be predicted by three-dimensional finite element modeling. These patient populations may require closer follow-up after IVCF placement to prevent or reduce the risk for filter complication or worsening perforation.

Complications of Celect, Günther tulip, and Greenfield inferior vena cava filters on CT follow-up: a single-institution experience.

PURPOSE: To evaluate and compare the rates of complications on follow-up computed tomography (CT) studies of patients with Celect, Günther Tulip, and Greenfield inferior vena cava (IVC) filters. MATERIALS AND METHODS: Retrospective review of CT studies obtained 0-1,987 days after infrarenal placement of an IVC filter identified 255 Celect, 160 Tulip, and 50 Greenfield filters. Follow-up CT studies were independently evaluated by two observers for IVC perforation, contact with adjacent organs, and filter fracture. Multivariate analysis was performed to identify factors associated with higher rates of IVC perforation, including age, IVC diameter, sex, and history of malignancy. RESULTS: IVC perforation was observed in 126 of 255 Celect filters (49%) with a mean follow-up of 277 days, 69 of 160 Tulip filters (43%) with a mean follow-up of 437 days, and one of 50 Greenfield filters (2%) with a mean follow-up of 286 days. A significantly higher IVC perforation rate was observed in women (45.5%) compared with men (30.8%; P = .002) and in patients with a history of malignancy (43.7%) compared with patients with no history of malignancy (29.9%; P < .001). Filter fracture was rare, observed in two of 255 Celect filters (0.8%), one of 160 Tulip filters (0.6%), and none of 50 Greenfield filters. CONCLUSIONS: No significant difference was observed in IVC perforation rate between Celect and Tulip filters. Greenfield filters had a significantly lower rate of IVC perforation than Celect and Tulip filters. Higher IVC perforation rates were observed in women and patients with a history of malignancy.