Syndicate content
Recent documents in eScholarship@UMMS
Updated: 3 hours 22 min ago

Dosimetric properties of high energy current (HEC) detector in keV x-ray beams

Mon, 05/22/2017 - 11:55am

We introduce a new x-ray radiation detector. The detector employs high-energy current (HEC) formed by secondary electrons consisting predominantly of photoelectrons and Auger electrons, to directly convert x-ray energy to detector signal without externally applied power and without amplification. The HEC detector is a multilayer structure composed of thin conducting layers separated by dielectric layers with an overall thickness of less than a millimeter. It can be cut to any size and shape, formed into curvilinear surfaces, and thus can be designed for a variety of QA applications. We present basic dosimetric properties of the detector as function of x-ray energy, depth in the medium, area and aspect ratio of the detector, as well as other parameters. The prototype detectors show similar dosimetric properties to those of a thimble ionization chamber, which operates at high voltage. The initial results obtained for kilovoltage x-rays merit further research and development towards specific medical applications.

Breast: Sezary Syndrome: A Unique Presentation

Mon, 05/22/2017 - 11:55am

Sezary syndrome is a subtype of cutaneous T cell lymphoma which usually presents as generalized skin disease with erytheroderma. Distal organ involvement is rare and is usually a late finding in the course of the disease. Breast involvement is extremely rare. Herein, we present a case report of a patient whose initial presentation involved an intramammary lymph node prior to the onset of more characteristic skin disease. Sezary syndrome was confirmed by cythopathologic findings.

Technical Note: Nanometric organic photovoltaic thin film detectors for dose monitoring in diagnostic x-ray imaging

Mon, 05/22/2017 - 11:55am

PURPOSE: To fabricate organic photovoltaic (OPV) cells with nanometric active layers sensitive to ionizing radiation and measure their dosimetric characteristics in clinical x-ray beams in the diagnostic tube potential range of 60-150 kVp.

METHODS: Experiments were designed to optimize the detector's x-ray response and find the best parameter combination by changing the active layer thickness and the area of the electrode. The OPV cell consisted of poly (3-hexylthiophene-2,5-diyl): [6,6]-phenyl C61 butyric acid methyl ester photoactive donor and acceptor semiconducting organic materials sandwiched between an aluminum electrode as an anode and an indium tin oxide electrode as a cathode. The authors measured the radiation-induced electric current at zero bias voltage in all fabricated OPV cells.

RESULTS: The net OPV current as a function of beam potential (kVp) was proportional to kVp(-0.5) when normalized to x-ray tube output, which varies with kVp. Of the tested configurations, the best combination of parameters was 270 nm active layer thicknesses with 0.7 cm(2) electrode area, which provided the highest signal per electrode area. For this cell, the measured current ranged from approximately 0.7 to 2.4 nA/cm(2) for 60-150 kVp, corresponding to about 0.09 nA-0.06 nA/mGy air kerma, respectively. When compared to commercial amorphous silicon thin film photovoltaic cells irradiated under the same conditions, this represents 2.5 times greater sensitivity. An additional 40% signal enhancement was observed when a 1 mm layer of plastic scintillator was attached to the cells' beam-facing side.

CONCLUSIONS: Since both OPVs can be produced as flexible devices and they do not require external bias voltage, they open the possibility for use as thin film in vivo detectors for dose monitoring in diagnostic x-ray imaging.

Effect of Non-Alignment/Alignment of Attenuation Map Without/With Emission Motion Correction in Cardiac SPECT/CT

Mon, 05/22/2017 - 11:55am

PURPOSE: We investigate the differences without/with respiratory motion correction in apparent imaging agent localization induced in reconstructed emission images when the attenuation maps used for attenuation correction (from CT) are misaligned with the patient anatomy during emission imaging due to differences in respiratory state.

METHODS: We investigated use of attenuation maps acquired at different states of a 2 cm amplitude respiratory cycle (at end-expiration, at end-inspiration, the center map, the average transmission map, and a large breath-hold beyond range of respiration during emission imaging) to correct for attenuation in MLEM reconstruction for several anatomical variants of the NCAT phantom which included both with and without non-rigid motion between heart and sub-diaphragmatic regions (such as liver, kidneys etc). We tested these cases with and without emission motion correction and attenuation map alignment/non-alignment.

RESULTS: For the NCAT default male anatomy the false count-reduction due to breathing was largely removed upon emission motion correction for the large majority of the cases. Exceptions (for the default male) were for the cases when using the large-breathhold end-inspiration map (TI_EXT), when we used the end-expiration (TE) map, and to a smaller extent, the end-inspiration map (TI). However moving the attenuation maps rigidly to align the heart region, reduced the remaining count-reduction artifacts. For the female patient count-reduction remained post motion correction using rigid map-alignment due to the breast soft-tissue misalignment. Quantitatively, after the transmission (rigid) alignment correction, the polar-map 17-segment RMS error with respect to the reference (motion-less case) reduced by 46.5% on average for the extreme breathhold case. The reductions were 40.8% for end-expiration map and 31.9% for end-inspiration cases on the average, comparable to the semi-ideal case where each state uses its own attenuation map for correction.

CONCLUSIONS: Two main conclusions are that even rigid emission motion correction to rigidly align the heart region to the attenuation map helps in average cases to reduce the count-reduction artifacts and secondly, within the limits of the study (ex. rigid correction) when there is lung tissue inferior to the heart as with the NCAT phantom employed in this study endexpiration maps (TE) might best be avoided as they may create more artifacts than the end-inspiration (TI) maps.

Monte Carlo simulation of a prototypical patient dosimetry system for fluoroscopic procedures

Mon, 05/22/2017 - 11:55am

The purpose of this study is to investigate feasibility of a novel real-time dosimetry method for fluoroscopically guided interventions utilizing thin-film detector arrays in several potential locations with respect to the patient and x-ray equipment. We employed Monte Carlo (MC) simulation to establish the fluoroscopic beam model to determine dosimetric quantities directly from measured doses in thin-film detector arrays at three positions: A-attached to the x-ray source, B-on the couch under the patient and C-attached to the fluoroscopic imager. Next, we developed a calibration method to determine skin dose at the entry of the beam ([Formula: see text]) as well as the dose distribution along each ray of the beam in a water-equivalent patient model. We utilized the concept of water-equivalent thickness to determine the dose inside the patient based on doses measured outside of the patient by the thin-film detector array layers: (a) A, (b) B, or (c) B and C. In the process of calibration we determined a correction factor that characterizes the material-specific response of the detector, backscatter factor and attenuation factor for slab water phantoms of various thicknesses. Application of this method to an anthropomorphic phantom showed accuracy of about 1% for [Formula: see text] and up to about 10% for integral dose along the beam path when compared to a direct simulation of dose by MC.

Comparison of the scanning linear estimator (SLE) and ROI methods for quantitative SPECT imaging

Mon, 05/22/2017 - 11:54am

In quantitative emission tomography, tumor activity is typically estimated from calculations on a region of interest (ROI) identified in the reconstructed slices. In these calculations, unpredictable bias arising from the null functions of the imaging system affects ROI estimates. The magnitude of this bias depends upon the tumor size and location. In prior work it has been shown that the scanning linear estimator (SLE), which operates on the raw projection data, is an unbiased estimator of activity when the size and location of the tumor are known. In this work, we performed analytic simulation of SPECT imaging with a parallel-hole medium-energy collimator. Distance-dependent system spatial resolution and non-uniform attenuation were included in the imaging simulation. We compared the task of activity estimation by the ROI and SLE methods for a range of tumor sizes (diameter: 1-3 cm) and activities (contrast ratio: 1-10) added to uniform and non-uniform liver backgrounds. Using the correct value for the tumor shape and location is an idealized approximation to how task estimation would occur clinically. Thus we determined how perturbing this idealized prior knowledge impacted the performance of both techniques. To implement the SLE for the non-uniform background, we used a novel iterative algorithm for pre-whitening stationary noise within a compact region. Estimation task performance was compared using the ensemble mean-squared error (EMSE) as the criterion. The SLE method performed substantially better than the ROI method (i.e. EMSE(SLE) was 23-174 times lower) when the background is uniform and tumor location and size are known accurately. The variance of the SLE increased when a non-uniform liver texture was introduced but the EMSE(SLE) continued to be 5-20 times lower than the ROI method. In summary, SLE outperformed ROI under almost all conditions that we tested.

Novel DNA Polymer for Amplification Pretargeting

Mon, 05/22/2017 - 11:54am

In this Letter, different from conventional pretargeting, an additional novel DNA polymer with multiple copies of a target was first designed to be administrated between the antitumor antibody, and the labeled effector served as an amplification pretargeting strategy. Two phosphorothioate DNA strands, a bridging and a target strand, were hybridized to form a polymer. Polymer size, as a function of molar ratios, was then monitored by size exclusion HPLC and electrophoretic mobility shift assay. Moreover, binding efficiency of polymers with the radiolabeled effector and polymer size after hybridization were measured by HPLC as well. As the polymer was expected to produce more binding sites that would be targeted by effectors, amplification pretargeting can greatly improve accumulation of effectors in tumor. This novel proof-of-concept was then well demonstrated by the in vitro test of signal amplification in antibody-binding protein L coated plate and LS174T cells. Compared to conventional pretargeting, significantly increasing radioactive signal was observed in this designed amplification pretargeting, which would serve as a useful paradigm of the potential of oligomer polymers to improve pretargeting and other related approaches.

Multifocal Langerhans Cell Histiocytosis in an Adult

Mon, 05/22/2017 - 11:54am

Eosinophilic granuloma (EG) is the most common and benign form of the spectrum of disorders referred to as Langerhans cell histiocytosis (LCH). Langerhans cell histiocytosis is primarily regarded as a pediatric disease, with few adult cases of multifocal EG of bone reported. We report a case of multifocal EG in a 48-year-old woman, who presented with right knee pain. Radiographs showed a small lytic lesion in the medial femoral condyle. Diagnosis was confirmed by ultrasound-guided biopsy. She had had a previous EG lesion excised from her skull. Whole-body bone scan demonstrated a new skull lesion in the right diploic space, which was confirmed by magnetic resonance imaging. The patient underwent curettage, bone grafting, and prophylactic internal fixation of the right distal femur lesion. The skull lesion was treated with repeat craniectomy. Two years later, she developed a new lesion in the right distal femoral metaphysis, which was treated with intralesional corticosteroid injections. Now, more than 1 year later, the patient is pain-free with no evidence of new or recurrent disease. Because multifocal EG is a rare diagnosis in adults, appropriate clinical suspicion, in combination with radiographic findings and histologic examination, is essential for correct diagnosis and treatment.

What to Expect When They are Expecting: Magnetic Resonance Imaging of the Acute Abdomen and Pelvis in Pregnancy

Mon, 05/22/2017 - 11:54am

In this article, we discuss the challenges in the diagnosis of acute abdominopelvic pain in pregnant patients, role of imaging, and advantages of MRI over other modalities. Methods consist of pictorial review. We review the differential diagnoses and illustrate the MRI findings in pregnant patients with acute abdominopelvic pain, including gastrointestinal, gynecologic, urologic, and vascular etiologies.

Phenoxide-Bridged Zinc(II)-Bis(dipicolylamine) Probes for Molecular Imaging of Cell Death

Mon, 05/22/2017 - 11:54am

Cell death is involved in many pathological conditions, and there is a need for clinical and preclinical imaging agents that can target and report cell death. One of the best known biomarkers of cell death is exposure of the anionic phospholipid phosphatidylserine (PS) on the surface of dead and dying cells. Synthetic zinc(II)-bis(dipicolylamine) (Zn2BDPA) coordination complexes are known to selectively recognize PS-rich membranes and act as cell death molecular imaging agents. However, there is a need to improve in vivo imaging performance by selectively increasing target affinity and decreasing off-target accumulation. This present study compared the cell death targeting ability of two new deep-red fluorescent probes containing phenoxide-bridged Zn2BDPA complexes. One probe was a bivalent version of the other and associated more strongly with PS-rich liposome membranes. However, the bivalent probe exhibited self-quenching on the membrane surface, so the monovalent version produced brighter micrographs of dead and dying cells in cell culture and also better fluorescence imaging contrast in two living animal models of cell death (rat implanted tumor with necrotic core and mouse thymus atrophy). An (111)In-labeled radiotracer version of the monovalent probe also exhibited selective cell death targeting ability in the mouse thymus atrophy model, with relatively high amounts detected in dead and dying tissue and low off-target accumulation in nonclearance organs. The in vivo biodistribution profile is the most favorable yet reported for a Zn2BDPA complex; thus, the monovalent phenoxide-bridged Zn2BDPA scaffold is a promising candidate for further development as a cell death imaging agent in living subjects.

Onyx embolization in distal dissecting posterior inferior cerebellar artery aneurysms

Mon, 05/22/2017 - 11:54am

BACKGROUND: Dissecting aneurysms located along the distal segments of the posterior inferior cerebellar artery (PICA) are extremely rare, accounting for only 0.5-0.7% of all intracranial aneurysms. Treatment of these aneurysms is challenging, both surgically and endovascularly. We present our preliminary experience and clinical data utilizing Onyx as an embolization agent in the treatment of these lesions with proximal parent artery preservation.

METHODS: 7 consecutive ruptured peripheral PICA aneurysms, in 7 patients, were treated with superselective Onyx embolization at our institutions. According to the anatomical classification of Lister et al, these aneurysms were located in the lateral medullary segment (n=1), tonsillomedullary segment (n=1), and the telovelotonsillary segment (n=5) of the PICA. Technical feasibility, procedure related complications, angiographic results, follow-up diagnostic imaging, and clinical outcome were evaluated.

RESULTS: In all cases, endovascular treatment was successful, with complete occlusion of the aneurysm with proximal parent artery preservation at the final postprocedural angiogram. Procedure related complications were not observed. One patient with a poor clinical condition at admission died during the initial hospital stay due to extensive subarachnoid and intraventricular hemorrhage. No rebleeding or recanalization was noted during follow-up. Two patients had a residual moderate to severe disability at follow-up. Favorable outcomes, with no or mild disability, were observed in four of the surviving patients.

CONCLUSIONS: Angiographic, diagnostic imaging, and clinical results of our small series indicate that Onyx embolization of dissecting distal PICA aneurysms with parent artery preservation is an effective option with acceptable morbidity and mortality rate, in those cases in which surgical clipping or endovascular coiling of the aneurysmal sac is not suitable.

Evaluation of Rigid-Body Motion Compensation in Cardiac Perfusion SPECT Employing Polar-Map Quantification

Mon, 05/22/2017 - 11:54am

We have recently been successful in the development and testing of rigid-body motion tracking, estimation and compensation for cardiac perfusion SPECT based on a visual tracking system (VTS). The goal of this study was to evaluate in patients the effectiveness of our rigid-body motion compensation strategy. Sixty-four patient volunteers were asked to remain motionless or execute some predefined body motion during an additional second stress perfusion acquisition. Acquisitions were performed using the standard clinical protocol with 64 projections acquired through 180 degrees. All data were reconstructed with an ordered-subsets expectation-maximization (OSEM) algorithm using 4 projections per subset and 5 iterations. All physical degradation factors were addressed (attenuation, scatter, and distance dependent resolution), while a 3-dimensional Gaussian rotator was used during reconstruction to correct for six-degree-of-freedom (6-DOF) rigid-body motion estimated by the VTS. Polar map quantification was employed to evaluate compensation techniques. In 54.7% of the uncorrected second stress studies there was a statistically significant difference in the polar maps, and in 45.3% this made a difference in the interpretation of segmental perfusion. Motion correction reduced the impact of motion such that with it 32.8 % of the polar maps were statistically significantly different, and in 14.1% this difference changed the interpretation of segmental perfusion. The improvement shown in polar map quantitation translated to visually improved uniformity of the SPECT slices.

T1-Weighted Dynamic Contrast-Enhanced MRI Is a Noninvasive Marker of Epidermal Growth Factor Receptor vIII Status in Cancer Stem Cell-Derived Experimental Glioblastomas

Mon, 05/22/2017 - 11:54am

We read with great interest the article by Arevalo-Perez et al, describing the potential value of T1-weighted dynamic contrast-enhanced MR imaging (DCE-MR imaging) as a biomarker for epidermal growth factor receptor variant III (EGFRvIII) mutation in patients with glioblastoma (GBM).

CAD-RADS(TM) Coronary Artery Disease - Reporting and Data System. An expert consensus document of the Society of Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR) and the North American Society for Cardiovascular Imaging (

Mon, 05/22/2017 - 11:54am

The intent of CAD-RADS - Coronary Artery Disease Reporting and Data System is to create a standardized method to communicate findings of coronary CT angiography (coronary CTA) in order to facilitate decision-making regarding further patient management. The suggested CAD-RADS classification is applied on a per-patient basis and represents the highest-grade coronary artery lesion documented by coronary CTA. It ranges from CAD-RADS 0 (Zero) for the complete absence of stenosis and plaque to CAD-RADS 5 for the presence of at least one totally occluded coronary artery and should always be interpreted in conjunction with the impression found in the report. Specific recommendations are provided for further management of patients with stable or acute chest pain based on the CAD-RADS classification. The main goal of CAD-RADS is to standardize reporting of coronary CTA results and to facilitate communication of test results to referring physicians along with suggestions for subsequent patient management. In addition, CAD-RADS will provide a framework of standardization that may benefit education, research, peer-review and quality assurance with the potential to ultimately result in improved quality of care.

Reducing Radiation Exposure Without Compromising Image Quality for Lumbar Spine CT

Mon, 05/22/2017 - 11:54am

In light of the heightened awareness of radiation’s cancer-causing potential and the dramatic increase in the number of CT studies, minimizing radiation exposure is a paramount objective in radiology. An issue that complicates this goal is that image quality is a function of the dose of radiation. In other words, larger doses result in higher quality images. The goal then is to strike a balance to maximize patient safety: reduce radiation without compromising the quality of the image.

ACR Appropriateness Criteria Clinically Suspected Pulmonary Arteriovenous Malformation

Mon, 05/22/2017 - 11:54am

Pulmonary arteriovenous malformations are often included in the differential diagnosis of common clinical presentations, including hypoxemia, hemoptysis, brain abscesses, and paradoxical stroke, as well as affecting 30% to 50% of patients with hereditary hemorrhagic telangiectasia (HHT). Various imaging studies are used in the diagnostic and screening settings, which have been reviewed by the ACR Appropriateness Criteria Vascular Imaging Panel. Pulmonary arteriovenous malformation screening in patients with HHT is commonly performed with transthoracic echocardiographic bubble study, followed by CT for positive cases. Although transthoracic echocardiographic bubble studies and radionuclide perfusion detect right-to-left shunts, they do not provide all of the information needed for treatment planning and may remain positive after embolization. Pulmonary angiography is appropriate for preintervention planning but not as an initial test. MR angiography has a potential role in younger patients with HHT who may require lifelong surveillance, despite lower spatial resolution compared with CT. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Grading of Regional Apposition after Flow-Diverter Treatment (GRAFT): a comparative evaluation of VasoCT and intravascular OCT

Mon, 05/22/2017 - 11:54am

BACKGROUND: Poor vessel wall apposition of flow diverter (FD) stents poses risks for stroke-related complications when treating intracranial aneurysms, necessitating long-term surveillance imaging. To facilitate quantitative evaluation of deployed devices, a novel algorithm is presented that generates intuitive two-dimensional representations of wall apposition from either high-resolution contrast-enhanced cone-beam CT (VasoCT) or intravascular optical coherence tomography (OCT) images.

METHODS: VasoCT and OCT images were obtained after FD implant (n=8 aneurysms) in an experimental sidewall aneurysm model in canines. Surface models of the vessel wall and FD device were extracted, and the distance between them was presented on a two-dimensional flattened map. Maps and cross-sections at potential locations of malapposition detected on VasoCT-based maps were compared. The performance of OCT-based apposition detection was evaluated on manually labeled cross-sections using logistic regression against a thresholded ( > /=0.25 mm) apposition measure.

RESULTS: VasoCT and OCT acquisitions yielded similar Grading of Regional Apposition after Flow-Diverter Treatment (GRAFT) apposition maps. GRAFT maps from VasoCT highlighted 16 potential locations of malapposition, of which two were found to represent malapposed device struts. Logistic regression showed that OCT could detect malapposition with a sensitivity of 98% and a specificity of 81%.

CONCLUSIONS: GRAFT delivered quantitative and visually convenient representations of potential FD malapposition and occasional acute thrombus formation. A powerful combination for future neuroendovascular applications is foreseen with the superior resolution delivered by intravascular OCT.

Detection of Klebsiella. Pneumoniae Infection with an Antisense Oligomer Against its Ribosomal RNA

Mon, 05/22/2017 - 11:54am

PURPOSE: Previously, we demonstrated specific accumulation into bacteria of a 12-mer phosphorodiamidate morpholino (MORF) oligomer complementary to a ribosomal RNA (rRNA) segment found in all bacteria using the universal probe called Eub338 (Eub). Here, two MORF oligomers Eco and Kpn with sequences specific to the rRNA of Escherichia coli (Eco) and Klebsiella pneumoniae (Kpn) were investigated along with Eub and control (nonEub).

PROCEDURES: To determine bacterial rRNA binding, oligomers were tagged with Alexa Fluor 633 (AF633) for fluorescence in situ hybridization (FISH) and fluorescence microscopy, and radiolabeled with technetium-99m (Tc-99m) for biodistribution and SPECT imaging in infected mice.

RESULTS: By both FISH and fluorescence microscopy, Eub showed a positive signal in both E. coli and K. pneumoniae as expected, and Kpn showed significantly higher accumulation in K. pneumoniae with near background in E. coli (p < 0.01). Conversely, Eco was positive in both E. coli and K. pneumoniae, hence nonspecific. As determined by biodistribution, the accumulation of [(99m)Tc]Kpn was higher in the thigh infected with live K. pneumoniae than with live E. coli (p = 0.05), and significantly higher than with heat-killed K. pneumoniae (p = 0.02) in the target thigh. By SPECT imaging, the accumulation of [(99m)Tc]Kpn was obviously higher in its specific target of K. pneumoniae compared to an E. coli infected thigh.

CONCLUSIONS: Kpn complementary to the rRNA of K. pneumoniae, labeled with Tc-99m or AF633, demonstrated specific binding to fixed and live K. pneumoniae in culture and in infected mice such that Tc-99m-labeled Kpn as the MORF oligomer may be useful for K. pneumoniae infection detection through imaging.

The Relevance of Readmissions after Common IR Procedures: Readmission Rates and Association with Early Mortality

Mon, 05/22/2017 - 11:54am

PURPOSE: To determine all-cause readmission rates for 12 IR procedures and association of time to readmission with risk-adjusted 90-day mortality.

MATERIALS AND METHODS: Patients discharged after 12 inpatient IR procedures at a tertiary-care hospital between June 2008 and May 2013 (N = 4,163) were categorized as no readmission (n = 1,479; 40.5%) or readmission between 0 and 7 (n = 379; 10.4%), 8 and 30 (n = 650; 17.8%), 31 and 60 (n = 378; 10.3%), 61 and 90 (n = 169; 4.6%), or 91 and 180 days (n = 280; 7.7%). Readmission rate >/= 15% was considered high based on published national readmission rates for procedures. Risk-adjusted 90-day mortality for each interval was calculated for transjugular intrahepatic portosystemic shunt (TIPS), transjugular and percutaneous liver biopsy (TJLB, PLB), ports, inferior vena cava (IVC) filter, lower extremity angioplasty (LEA), arteriovenous fistulagrams, vascular embolization (VE), percutaneous cholecystostomy (PC), percutaneous transhepatic biliary drainage (PTBD), primary urinary drainage, and feeding tube placement. Covariates included age, sex, race, insurance status, and Charlson Comorbidity Index.

RESULTS: All procedures had high 30-day readmission rates (15%-50.5%). Readmissions were highest for ports (50.5%), TJLB (43.4%), PTBD (38.5%), PC (31.9%), and TIPS (31.3%). Readmissions occurred most frequently 8-30 days after discharge for all procedures except VE (31-60 d; 10.6%), PC (31-60 d; 23.4%), and LEA (91-180 d; 15.1%). On multivariate analysis, 30-day readmissions for LEA (AOR 3.19; 95% CI, 1.2-8.2; P = .02), VE (AOR 10.01; 95% CI, 3.1-32.9; P < .001), IVC filter (AOR 2.98; 95% CI, 1.3-6.9; P = .01), PLB (AOR 2.86; 95% CI, 1.71-4.79; P < .001), and PCN (AOR 3.09; 95% CI, 1.29-7.37; P = .01) were associated with 90-day mortality.

CONCLUSIONS: Inpatient IR procedures have high 30-day all-cause readmission rates, which can be associated with increased 90-day mortality. Further evaluation to determine preventable causes for readmission may impact 90-day mortality.

Effects of breast density and compression on normal breast tissue hemodynamics through breast tomosynthesis guided near-infrared spectral tomography

Mon, 05/22/2017 - 11:53am

Optically derived tissue properties across a range of breast densities and the effects of breast compression on estimates of hemoglobin, oxygen metabolism, and water and lipid concentrations were obtained from a coregistered imaging system that integrates near-infrared spectral tomography (NIRST) with digital breast tomosynthesis (DBT).