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Contrast material–enhanced spectral mammography can be integrated into routine diagnostic imaging and is valuable for evaluating the extent of disease in women with newly diagnosed breast cancer; in addition, contrast-enhanced spectral mammography appears to represent an acceptable substitute for MR imaging in the setting of contraindications to MR imaging.

Clinical data that are generated through routine radiation therapy procedures can be leveraged as a source of knowledge to provide evidence-based decision support for future patients. Treatment planning in radiation therapy often relies on trial-and-error iterations, experience, judgment calls and general guidelines. The authors present a knowledge-driven decision support system that assists clinicians by reducing some of the uncertainties associated with treatment planning and provides quantified empirical estimates to help minimize the radiation dose to healthy critical structures surrounding the tumor. A database of retrospective DICOM RT data fuels a decision support engine, which assists clinicians in selecting dose constraints and assessing dose distributions. The first step is to quantify the spatial relationships between the tumor and surrounding critical structures through features that account for distance, volume, overlap, location, shape and orientation. These features are used to identify database cases that are anatomically similar to the new patient. The dose profiles of these database cases can help clinicians to estimate an acceptable dose distribution for the new case, based on empirical evidence. Since database diversity is essential for good system performance, an infrastructure for multi-institutional collaboration was also conceptualized in order to pave the way for data sharing of protected health information. A set of 127 retrospective test cases was collected from a single institution in order to conduct a leave-one-out evaluation of the decision support module. In 72 % of these retrospective test cases, patients with similar tumor anatomy were also found to exhibit similar radiation dose distributions. This demonstrates the system’s ability to successfully extract retrospective database cases that can estimate the new patient’s dose distribution. The radiation therapy treatment planning decision support system presented here can assist clinicians in determining good dose constraints and assessing dose distributions by using knowledge gained from retrospective treatment plans.

The use of topical nitroglycerin paste for the treatment of early ischemic filler complications may not improve the perfusion in ischemic areas. We caution the use of nitroglycerin paste in patients presenting with ischemic filler complications.

A pulsed terahertz (THz) imaging system and millimeter-wave reflectometer were used to acquire images and point measurements, respectively, of five rabbit cornea in vivo. These imaging results are the first ever produced of in vivo cornea. A modified version of a standard protocol using a gentle stream of air and a Mylar window was employed to slightly dehydrate healthy cornea. The sensor data and companion central corneal thickness (CCT) measurements were acquired every 10-15 min over the course of two hours using ultrasound pachymmetry.. Statistically significant positive correlations were established between CCT measurements and millimeter wave reflectivity. Local shifts in reflectivity contrast were observed in the THz imagery; however, the THz reflectivity did not display a significant correlation with thickness in the region probed by the 100 GHz and CCT measurements. This is explained in part by a thickness sensitivity at least 10 × higher in the mm-wave than the THz systems. Stratified media and effective media modeling suggest that the protocol perturbed the thickness and not the corneal tissue water content (CTWC). To further explore possible etalon effects, an additional rabbit was euthanized and millimeter wave measurements were obtained during death induced edema. These observations represent the first time that the uncoupled sensing of CTWC and CCT have been achieved in vivo.

Terahertz (THz) spectral properties of human cornea are explored as a function of central corneal thickness (CCT) and corneal water content, and the clinical utility of THz-based corneal water content sensing is discussed. Three candidate corneal tissue water content (CTWC) perturbations, based on corneal physiology, are investigated that affect the axial water distribution and total thickness. The THz frequency reflectivity properties of the three CTWC perturbations were simulated and explored with varying system center frequency and bandwidths (Q-factors). The modeling showed that at effective optical path lengths on the order of a wavelength the cornea presents a lossy etalon bordered by air at the anterior and the aqueous humor at the posterior. The simulated standing wave peak-to-valley ratio is pronounced at lower frequencies and its effect on acquired data can be modulated by adjusting the bandwidth of the sensing system. These observations are supported with experimental spectroscopic data. The results suggest that a priori knowledge of corneal thickness can be utilized for accurate assessments of corneal tissue water content. The physiologic variation of corneal thickness with respect to the wavelengths spanned by the THz band is extremely limited compared to all other structures in the body making CTWC sensing unique amongst all proposed applications of THz medical imaging.

Settling cues in the form of coralline algae were presented to groups of hatchery-reared red abalone (Haliolis rufescens, Swainson 1822) larvae daily from day 4 to day 32 posthatch (temperature, 14°C). Survival of postlarval abalone after settlement was monitored for 30 days to quantify the effect of delayed metamorphosis on the subsequent survival of benthic juvenile abalone. After exposure to live coralline algae, an average of 85% of the larvae metamorphosed and settled the following day. The number of settled postlarvae increased gradually the longer the settling cue was withheld. Postsettlement juveniles were raised in individual containers on mixed diatoms for up to 34 days. Red abalone larvae remained competent to settle 32 days after fertilization. Larvae that metamorphosed from day 4 through day 19 had longer survival during the next 30 days (average, 19%) than those presented with a settling cue from day 20 to day 32 (average, 8%). Statistical analysis using a threshold cut point indicated that the 20-day threshold marked a significant change in subsequent postlarval survival. A receiver-operating characteristic curve analysis indicated that the 20-day cut point predicted high or low future survival of postmetamorphic abalone 73.4% of the time. Larvae that swam for less than 20 days had postmetamorphic survival of 8 days or more, whereas survival was 7 days or less for postmetamorphic abalone that had swam previously for 20-32 days. A larval competency period of 20 days is significantly longer than the 5-7-day larval stage often used to estimate transport times for this species. [ABSTRACT FROM AUTHOR]

Introduction:Although image-derived parameters such as wall shear stress (WSS), flow rate (FR), aspect ratio (AR), size ratio (SR), and non-sphericity index (NSI) were previously linked to risks of intracranial aneurysm (IA) growth, findings across studies have been inconsistent. Here, we revisit existing hemodynamic and morphological metrics and compare them between stable and growing IAs. We hypothesize that some may differentiate growing and stable trajectories of IAs.Methods:Unruptured IA cases between 2018-2020 were identified from UCLA Medical Center electronic medical records, with follow-up data used to determine growth status. From CTA/MRA images, models of 16 stable and 20 growing unruptured IA cases were reconstructed. Aneurysm diameter, height, neck width, surface area, volume, parent artery diameter, AR, SR, NSI, volume ratio, and surface area ratio were calculated. With data from hemodynamic simulations, we also measured FR and WSS. To capture spatial variations in hemodynamics, we calculated location-dependent mean deviation of WSS and FR at 3 locations within an aneurysm: neck, body, and dome. Pearson chi-square tests were used to compare background variables between groups. MANOVA was employed to compare the index values between stable and growing IAs.Results:Variables including location, diameter, race, history of smoking, and SAH were not significantly different between groups (p>>.05). Gender (p=0.06) and multiplicity (p=0.06) approached significance. Among the size-related and morphological parameters described above, only IA height (3.07±1.94mm vs. 5.49±3.61mm, p=0.03), neck width (4.93±1.42mm vs. 7.14±3.78mm, p=0.04), and size ratio (1.40±0.62 vs. 2.27±1.27, p =0.02) were significantly different (stable vs. growing, respectively). Growing IA had significantly higher FR spatial variation (0.43±0.35 vs. 0.75±0.44; p=0.03) and WSS spatial variations (0.24±0.20 vs. 0.49±0.28; p=0.008).Conclusions:Our findings support that location-dependent hemodynamic variations and SR may be potential risk factors of IA growth. Upon validation in larger studies, these parameters may aid in early identification of incidentally found IAs’ trajectories.

Introduction:Oscillations in blood flow over the cardiac cycle are relevant to endothelial function and vascular health. But, as yet the relationship between pulsatile flow characteristics and intracranial aneurysm (IA) growth is unclear. We analyzed time-based hemodynamic indices within unruptured IAs with known growth or stable trajectories. We hypothesize that combining pulsatile parameters can yield a predictive model for IA growth.Methods:Unruptured IA cases with at least 3 imaging studies were identified from UCLA Medical Center electronic medical records. Cases with an increase in diameter of at least 10% were assigned to the growing group and all other cases were assigned to the stable group. 16 stable and 20 growing cases from 2018-2020 qualified for the study. For each IA image study, computational fluid dynamic (CFD) flow simulation was performed and pulsatility index (PI) and wall shear stress PI (WSSPI) were recorded at 5 locations: inflow artery, IA neck, body, dome, and outflow artery. Values were compared with MANOVA. A stepwise logistic regression with growth as the outcome variable and WSSPI and PI at all locations as covariates was then performed.Results:PI was significantly higher in growing IA at the body (0.81±0.44 vs. 1.76±1.18, p=0.006) and dome (1.22±0.76 vs. 1.91±1.20 p=0.04). WSSPI was significantly higher in growing IA at the inflow artery (0.68±0.05 vs. 0.87±0.36, p=0.049), body (1.07±0.22 vs. 1.55±0.73, p=0.02), and dome (1.15±0.30 vs. 1.64±0.70, p=0.01). Logistic regression yielded a predictive model with 88.2% accuracy and AUC of 0.944: logit(growth) = 2.035 х PI_body+ 14.004 х WSSPI_inflow+ 4.263 х WSSPI_body-17.342.Conclusions:Based on a finding of elevated pulsatility in growing IA, we propose a model to predict subsequent IA growth. This should be further tested in larger CFD studies. Upon confirmation, the model may be helpful in guiding clinical decisions.

Background:Estimation of infarction based on computed tomographic perfusion (CTP) remains challenging, mainly due to noise associated with CTP data and variability in reported thresholds ischemic core esstimation. Commercial software companies have attempted to establish CTP thresholds; for example, a relative cerebral blood flow (rCBF) of <30% for RAPID™ (iSchemaView). In this retrospective multi-center study, we sought to establish and validate CTP threshold values for estimation of ischemic core using Olea Sphere® software (Olea Medical Solutions).Methods:Under an approved multi-institutional protocol, patients with acute ischemic stroke of the anterior circulation from three comprehensive stroke centers were included if they met the following criteria: baseline CTP, recanalization achieved (Thrombolysis in cerebral infarction scale ≥ IIb), and follow up MRI (DWI) performed. Perfusion maps were generated from the CTP data by the Bayesian probabilistic model and oscillation singular value decomposition (oSVD). CTP parameters, including time to peak (TTP), rCBF, time to max (Tmax), and Delay (equivalent of Tmax in Bayesian model) were generated. Brain was extracted from CTP and coregistered with the follow up MRI. An infarction mask and non-infarcted masks were drawn on MRI. We used a robust logistic regression to assess the binary outcome of our voxel-based analysis (infarcted vs non-infarcted) by adjusting for intra-subject correlations.Results:Eighty-one patients (42 Male; mean age 67.4 ±17.3) were included. All CTP parameters for the Bayesian and oSVD methods showed significant differences between infarcted and non-infarcted areas (p < 0.001). In the Bayesian model, a combination of rCBF at threshold of <45% and delay at threshold of 0.82 sec provided the highest diagnostic accuracy; AUC/sensitivity/specificity (0.79/0.69/0.79). In the oSVD method, a combination of rCBF at threshold of <16% and Tmax at threshold of 4.00 sec provided the highest diagnostic accuracy; AUC/sensitivity/specificity (0.71/0.64/0.73).Conclusion:Using heterogenous CTP data from three stroke centers, we established thresholds for estimation of ischemic core for Olea software that can be used for both Bayesian and oSVD postprocessing models.

Bone subtraction techniques have been shown to enhance cranial computed tomography angiography (CTA). The aims of this study were to assess the feasibility of bone subtraction CTA (BSCTA) in cervical CTA, test whether a late venous CT (LVCT) scan can be used as bone mask instead of a low-dose nonenhanced CT (NECT), and to evaluate the impact of patient motion on image quality.

Evaluation of coronary arteries at higher heart rates and in the presence of coronary stents remains problematic. The utilization of dual source computed tomography (DSCT) might improve the visualization of the coronary arteries under these conditions by imaging at a temporal resolution of 83 milliseconds, independent of heart rate.

Single-shot echo-planar based diffusion tensor imaging is prone to geometric and intensity distortions. Parallel imaging is a means of reducing these distortions while preserving spatial resolution. A quantitative comparison at 3 T of parallel imaging for diffusion tensor images (DTI) using k-space (generalized auto-calibrating partially parallel acquisitions; GRAPPA) and image domain (sensitivity encoding; SENSE) reconstructions at different acceleration factors, R, is reported here.

To ascertain the extent of publication bias in the reporting of acute stroke clinical trials.

The major goal of this work was to characterize invasive ductal carcinoma and healthy fatty breast tissues noninvasively using the classification and regression tree analysis (CART) of 2D MR spectral data. 2D L-COSY spectra were acquired in 14 invasive breast carcinoma and 21 healthy fatty breasts using a GE 1.5 Tesla MRI/MRS scanner equipped with a 2-channel phased-array breast MR coil. The 2D spectra were recorded in approximately 10 minutes using a minimum voxel size of 1 ml without any water suppression technique. For healthy breasts, spectra were acquired from at least one fatty region. 2D L-COSY spectra were recorded in a total of 43 voxels. Five diagonal and six cross peak volumes were integrated and at least eighteen ratios were selected as potential features for the statistical method, namely CART. The 2D L-COSY data showed a significant increase for the majority of these ratios in invasive breast carcinomas compared to healthy fatty tissues. Better accuracy of identifying carcinomas and fatty tissues is reported using CART analysis of different combinations of ratios calculated from the relative levels of water, choline, and saturated and unsaturated lipids. This is a first report on the statistical classification of 2D L-COSY in human breast carcinomas in vivo.

HIV-1 cardiomyopathy has become a major cause of death in AIDS patients, but its pathogenesis is unclear. We used an antigen retrieval technique and immunostaining to investigate the hearts of 15 AIDS patients, of whom 3 had dilated cardiomyopathy. Immunocytochemistry shows infiltration of the left ventricular myocardium with mononuclear cells, ranging from minimal to diagnostic of myocarditis. The infiltrates include macrophages and CD3+ and CD8+ T cells. The tight junction protein ZO-1 is disrupted at the site of monocyte-macrophage vascular penetration and the coronary vessels show fibrinogen leakage in the hearts of AIDS patients, but not in the normal heart. A subset of infiltrating macrophages is doubly positive for cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase. HIV-1 peptides gp120 and Nef are expressed in macrophages and T cells, but not in cardiomyocytes. COX-2 is expressed by both gp120-positive and gp120-negative macrophages. The hearts of AIDS patients separate into those showing minimal infiltrates with low COX-2 expression and those with dense infiltrates and high COX-2; all failing hearts are in the latter group. These data suggest that COX-2-activated and HIV-1-infected monocyte-macrophages and T cells play a crucial role in the progression of HIV-1 myocarditis to HIV-1 cardiomyopathy.

This study was undertaken to determine the peak kilovoltage (kVp) automatically selected when large, fatty breasts undergo imaging, to compare the accuracy of detecting calcification clusters when high- and low-kVp techniques are used for radiographing larger fatty breasts, and to suggest lower kVp values or filtration that will allow radiography of large, fatty breasts in less than 3 seconds. Five mammography units were tested to determine the kVps automatically selected by each unit’s computer for 6- and 8-cm breast thicknesses. Then cadaveric breasts underwent radiography at 25 and 28 kVp using a molybdenum anode with molybdenum filtration to create pairs of test images 6.2 to 7.3 cm thick. Twenty-three simulated calcification clusters were added to 16 of these pairs, whereas 16 were without added calcifications. Three radiologists viewed the two sets of images in an alternative forced choice experiment. Finally, the five mammography units were tested to determine lower-kVp techniques that would allow the radiography of 6- and 8-cm breast thicknesses in less than 3 seconds, as recommended by the American College of Radiography to prevent motion. In the imaging of 6-cm-thick breasts, phototimer kVp increased from 2 to 3 kVp over the kVp automatically selected for a 4-cm-thick breast and from 4 to 7 kVp for 8-cm-thick breasts. The 3-kVp increase in the cadaveric breast experiment significantly affected calcification detection. When the lower kVp was selected, there was an increased mean glandular dose of 16 to 90 for a 6-cm-thick breast, and 0 to 67 for an 8-cm-thick breast. Centers performing mammography should consider adjusting automatic exposure controls that select kVp so that image quality rather than reduced dose is optimized.

The objective of this study was to determine whether linear discriminant analysis of different independent features of MR images of breast lesions can increase the sensitivity and specificity of this technique. For MR images of 23 benign and 20 malignant breast lesions, three independent classes of features, including characteristics of Gd‐DTPA‐uptake curve, boundary, and texture were evaluated. The three classes included five, four and eight features each, respectively. Discriminant analysis was applied both within and across the three classes, to find the best combination of features yielding the highest classification accuracy. The highest specificity and sensitivity of the different classes considered independently were as follows: Gd‐up‐take curves, 83% and 70%; boundary features, 86% and 70%; and texture, 70% and 75%, respectively. A combination of one feature each from the first two classes and age yielded a specificity of 79% and sensitivity of 90%, whereas highest figures of 93% and 95%, respectively, were obtained when a total of 10 features were combined across different classes. Statistical analysis of different independent classes of features in MR images of breast lesions can improve the classification accuracy of this technique significantly.

The release by the Centers for Disease Control (CDC)1 of new guidelines on lead poisoning prompts us to express concern about the present direction of governmental control of lead exposure in children. Pediatricians, psychologists, and epidemiologists2-4 are uneasy about the ramifications of lowering the blood lead level at which we should become involved, through increased medical monitoring or environmental intervention. Parents are becoming concerned about the intellectual future of their children at the same time that they are faced with both an apparent inability to eliminate low levels of lead in children, and the dangers of removing lead from houses. To make things worse, it is now suggested that these effects persist for years, resulting in a poor performance in school and higher dropout rate for older children. Parents now see future prospects for their children permanently jeopardized.

A 54-year-old man developed basal cell carcinoma of the anal verge. This extremely rare tumor behaves rather innocently, whereas cloacogenic carcinoma of the anus, which resembles it histologically, metastasizes early and often proves fatal. Clinical and histopathologic characteristics of the two anal neoplasms are tabulated to facilitate differential diagnosis, and thereby promote their very different therapies.

To compare laparoscope-assisted transvaginal removal of dermoid cysts to more standard laparoscopic cystectomy techniques.

The respiratory status of residents of three areas exposed to (1) photochemical oxidants (Burbank, Calif), (2) sulfur dioxide, particulates, and hydrocarbons (Long Beach, Calif), and (3) low levels of pollutants (Lancaster, Calif) was determined using a modified National Heart and Lung Institute questionnaire, electronic volume spirometric studies, the single-breath nitrogen washout test, and body plethysmographic studies. Each area under study was within 2 km of a monitoring station of the Southern California Air Quality Management District. Seventy to 79 percent of the residents of enumerated households completed testing. Results of retesting a 3 percent probability sample at the Pulmonary Function Laboratory of the University of California, Los Angeles, indicated reasonable repeatability for all tests except the single-breath nitrogen test. Among the three areas, participants from Lancaster, Calif (low pollution), had the greatest number of “best” performance values and the least number of “worst” performance values for the tests. The distribution of best and worst performance among the three areas was similar for current smokers, those who had never smoked, and all participants for each of the tests. Mean test values of dysfunction of the small airways were either slightly better (single-breath nitrogen test) in the two polluted areas or similar (maximal expiratory flow rates at 50 percent and at 75 percent of forced vital capacity below total lung capacity) in all three areas. Mean plethysmographic values (thoracic gas volume, airway resistance, and specific airway resistance) were “worst” in participants from Burbank, Calif (photochemical oxidants); and spirometric values were “worst” in participants from Long Beach, Calif (sulfur dioxide, particulates, and hydrocarbons). Within the limitations of the cross-sectional study design, the results suggest that residence in the two polluted areas is associated with respiratory impairment, primarily of functions of the large airways.

Digital image compression reduces the storage requirements and network traffic on picture archiving and communications systems. Full-frame bitallocation (FFBA) is an irreversible image-compression method based on the discrete cosine transform that provides for high compression ratios with a high degree of image fidelity.

Data from its first four operating years indicate that the Sepulveda VA Geriatric Evaluation Unit is having consistent beneficial effects on patient care. These benefits include improved diagnostic accuracy, reduced use of drugs, improved functional status, and improved placement location. However, not all patients benefit equally, and differences between patient responses highlight the need to select those who will benefit most from relatively costly Geriatric Evaluation Unit services. Discriminant and regression analyses were performed on 98 consecutive patients to determine which patients admitted to the Geriatric Evaluation Unit would show greatest improvement in terms of placement, functional status, one‐year survival, and living location, and which patients would be treated most efficiently in terms of length of stay. Patient characteristics on admission significantly associated with discharge home included a relatively high functional and cognitive status, the absence of an unstable medical problem, and not being expected to need nursing home placement by the referring physician. The latter two factors alone predicted actual placement location on the next 101 patients admitted to the Geriatric Evaluation Unit with high predictive accuracy (88.5 per cent). Factors predictive of patients whose functional status would improve on the Geriatric Evaluation Unit included absence of an unstable medical problem and being over 75 years old (predictive accuracy was 82.5 per cent). Two major factors associated with long patient stays on the Geriatric Evaluation Unit were low functional status scores and not living in own home or with family. These analyses indicate criteria that may be useful in selecting patients for inpatient geriatric evaluation and rehabilitation programs.

Blood lead sampling has demonstrated an almost universal low-level elevation in inner-city children. The ingestion of lead paint chips is questioned as the main source of this exposure. Dust containing lead was found on the hands of inner-city children and interior household surfaces in substantially larger amounts than in similar suburban settings. It is possible that children may ingest this lead through typically frequent mouthing activity.

The accuracy of myocardial motion measurements, computed from cine-phase contrast (cine-PC) magnetic resonance (MR) velocity data, was compared with directly visualized motion of ME signal voids caused by implanted tantalum markers in anesthetized dogs.