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The purpose of this study is to evaluate the histopathologic diagnostic yield, sample size, procedural time, and dose-length product (DLP) for the biopsy of CT-occult lesions found at MRI or PET or both.A retrospective review of our radiology information system for biopsies of CT-occult lesions using CT guidance from January 1, 2010, through December 31, 2014, was performed and compared with a selection of CT-guided biopsies of CT-evident bone lesions during the same period. The data were then evaluated for diagnostic yield of histopathologic diagnosis, procedural time, use of sedation medication, DLP, and size of specimens obtained.A total of 30 CT-occult biopsies met the inclusion criteria. Twenty-seven of those biopsies had results that were concordant with the patient's primary histopathologic diagnosis, imaging findings, and clinical course. In the CT-evident lesion group, concordant histopathologic abnormalities were identified in 27 of 30 patients. There was a statistically significant increase in number of samples obtained for the CT-evident lesions compared with CT-occult lesions. There was no statistically significant difference in total specimen length, DLP, number of CT scans, procedural time, or use of sedation medication between the CT-occult and CT-evident biopsy groups.Biopsy of CT-occult lesions using anatomic landmarks achieves diagnostic yields similar to those for CT-guided biopsy of CT-evident lesions.

BACKGROUND Few studies exist with regard to the ability of electromyography (EMG) and volumetric magnetic resonance imaging (MRI) of the infraspinatus muscle to complement the physical assessment of active global shoulder external rotation (GER) in the neonatal brachial plexus palsy (NBPP) population. Therefore, the purpose of this study was to evaluate the relationships of EMG and MRI with active GER based on analysis of the infraspinatus muscle. METHODS Seventy-four NBPP patients (mean age, 5 y 1 m; range, 1 y 1 m to 13 y 3 m) who had undergone physical examination of the shoulder, EMG evaluation of the infraspinatus muscle, and shoulder MRI were included in this study. The outcome variable active GER was dichotomized into

Proliferative myositis, a pseudosarcomatous lesion of skeletal muscle, is quite rare in the pediatric population. While benign, it is not always recognized as such, and may be treated with an extensive resection that can result in permanent disfigurement. We report a case of an infant with the diagnosis of proliferative myositis, who to our knowledge is the youngest patient to be evaluated with magnetic resonance imaging (MRI). Although the MRI findings are non-specific, we highlight the importance of considering proliferative myositis in the differential diagnosis of a soft tissue mass, which ultimately might prevent an overly aggressive resection in a child.

Determination of the optical properties of thermally coagulated blood is becoming more important as the use of laser based methods to diagnose burn wounds has increased [1–3]. Knowledge of all optical properties within an inhomogeneous tissue sample, such as a burn wound, in combination with response of that tissue to laser light, allows for the identification of a specific chromophore, such as thermally coagulated blood, within the whole tissue sample. This is important for burn wound diagnosis because the boundary between the necrotic tissue layer, containing thermally coagulated blood, must be distinguished from the underlying viable tissue layer, which contains whole, viable blood[4]. Although the optical properties of whole blood have been studied extensively[5], there is a lack of research devoted to the study of the optical properties of thermally coagulated blood.Copyright © 2008 by ASME

Important to the laser based diagnosis of burn depth is an adequate understanding of the optical properties of thermally coagulated blood. Although the optical properties of photocoagulated blood have been studied in some detail, they are inadequate at completely characterizing the optical properties associated with the thermally coagulated blood of burn injuries. Using a photoacoustic method involving the addition of an absorber to thermally coagulated blood, we obtained data that will be used to derive a spectrum for the optical absorption coefficient, a, of thermally coagulated blood within the wavelength range from 580 to 700 nm. Before implementing this method, the stability of photoacoustic measurements within the diffusion theory realm was tested on two weakly absorbing, highly scattering Intralipid solutions. In addition, the absorber, Chlorazol Black, was tested for resistance to change caused by photobleaching and heating.

Discriminating viable from thermally coagulated blood in a burn wound can be used to profile burn depth, thus aiding the removal of necrotic tissue. In this study, we used a two-wavelength photoacoustic imaging method to discriminate coagulated and non-coagulated blood in a dermal burn phantom. Differences in the optical absorption spectra of coagulated and non-coagulated blood produce different values of the ratio of peak photoacoustic amplitude at 543 and 633 nm. The absorption values obtained from spectroscopic measurements indicate that the ratio of photoacoustic pressure for 543 and 633 nm for non-coagulated blood was 15.7:1 and 1.6:1 for coagulated blood. Using planar blood layers, we found the photoacoustic ratios to be 13.5:1 and 1.6:1, respectively. Using the differences in the ratios of coagulated and non-coagulated blood, we propose a scheme using statistical classification analysis to identify the different blood samples. Based upon these distinctly different ratios, we identified the planar blood samples with an error rate of 0%. Using a burn phantom with cylindrical vessels containing coagulated and non-coagulated blood, we achieved an error rate of 11.4%. These results have shown that photoacoustic imaging could prove to be a valuable tool in the diagnosis of burns.

Early and accurate determination of burn depth is crucial to monitoring the burn wound and aiding in the precise excision of necrotic tissue. A simplified model of a partial-thickness burn wound can be described as a layer of necrotic dermal tissue, containing thermally coagulated blood, atop a layer of inflamed dermal tissue characterized by the presence of viable (non-coagulated) blood. Using photoacoustic methods it is possible to discriminate between coagulated and non-coagulated blood and, therefore, discriminate between the two layer types. However, the effectiveness of such a photoacoustic method is limited by the thickness of the upper coagulated layer. Sufficient laser energy must be deposited into both layers to create detectable and characteristic signals from those layers. To determine the maximum thickness of the coagulated layer, at which the underlying non-coagulated layer was still able to generate detectable acoustic waves, we performed a Monte Carlo simulation on a human burn wound model with varying depths of the coagulated layer. The depths of the coagulated layer ranged from 100 to 1,100 mm, in 100 mm increments. Our analysis concluded that burn depth measurements can be achieved up to a burn depth of 900 mm with an incident radiant exposure of 0.255 J/cm2 at 543nm and 0.1275 J/cm2 at 633 nm.

This document is a compilation of radiochemical analyses of spent nuclear fuel samples performed at the Khlopin Radium Institute in St. Petersburg, Russia.

Through decades of effort in nuclear data development and simulations of reactor neutronics and accelerator transmutation, a collection of reaction data is continuing to evolve with the potential of direct applications to the production of medical isotopes. At Los Alamos the CINDER'90 code and library have been developed for nuclide inventory calculations using neutron-reaction (En < 20 MeV) and/or decay data for 3400 nuclides; coupled with the LAHET Code System (LCS), irradiations in neutron and proton environments below a few GeV are tractable; additional work with the European Activation File, the HMS-ALICE code and the reaction models of MCNPX (CEM95, BERTINI, or ISABEL with or without preequilibrium, evaporation and fission) have been used to produce evaluated reaction data for neutrons and protons to 1.7 GeV. At the Pacific Northwest National Laboratory, efforts have focused on production of medical isotopes and the identification of available neutron reaction data from results of integral measurements.