Portable UV-C device to treat high flow of infectious aerosols generated during clinical respiratory care.

Respiratory interventions including noninvasive ventilation, continuous positive airway pressure and high-flow nasal oxygen generated infectious aerosols may increase risk of airborne disease (SARS-CoV-2, influenza virus) transmission to healthcare workers. We developed and tested a prototype portable UV-C device to sterilize high flows of viral-contaminated air from a simulated patient source at airflow rates of up to 100 l/m. Our device consisted of a central quartz tube surrounded 6 high-output UV-C lamps, within a larger cylinder allowing recirculation past the UV-C lamps a second time before exiting the device.

Portable UV-C Device to Treat High Flow of Infectious Aerosols Generated during Clinical Respiratory Care.

Respiratory interventions including noninvasive ventilation, continuous positive airway pressure and high-flow nasal oxygen generated infectious aerosols may increase risk of airborne disease (SARS-CoV-2, influenza virus) transmission to healthcare workers. We developed/tested a prototype portable UV-C device to sterilize high flows of viral-contaminated air from a simulated patient source at airflow rates of up to 100 l/m. Our device consisted of a central quartz tube surrounded 6 high-output UV-C lamps, within a larger cylinder allowing recirculation past the UV-C lamps a second time before exiting the device.

A Novel Port to Facilitate Magnetic Hyperthermia Therapy for Glioma.

High-grade gliomas (HGG) are the most common primary brain malignancy and continue to be associated with a dismal prognosis (median survival rate of 15-18 months) with standard of care therapy. Magnetic hyperthermia therapy (MHT) is an emerging intervention that leverages the ferromagnetic properties of magnetic iron-oxide nanoparticles (MIONPs) to target cancer cells that are otherwise left behind after resection. We report a novel port device to facilitate localization, delivery, and temperature measurement of MIONPs within a target lesion for MHT therapy.

Designing a Bioreactor to Improve Data Acquisition and Model Throughput of Engineered Cardiac Tissues.

Heart failure remains the leading cause of death worldwide, creating a pressing need for better preclinical models of the human heart. Tissue engineering is crucial for basic science cardiac research; in vitro human cell culture eliminates the interspecies differences of animal models, while a more tissue-like 3D environment (e.g.

Validation of a Temperature-Feedback Controlled Automated Magnetic Hyperthermia Therapy Device.

We present in vivo validation of an automated magnetic hyperthermia therapy (MHT) device that uses real-time temperature input measured at the target to control tissue heating. MHT is a thermal therapy that uses heat generated by magnetic materials exposed to an alternating magnetic field. For temperature monitoring, we integrated a commercial fiber optic temperature probe containing four gallium arsenide (GaAs) temperature sensors.

3D Printing a Mechanically-Tunable Acrylate Resin on a Commercial DLP-SLA Printer.

Multi-material 3D printing with several mechanically distinct materials at once has expanded the potential applications for additive manufacturing technology. Fewer material options exist, however, for additive systems that employ vat photopolymerization (such as stereolithography, SLA, and digital light projection, DLP, 3D printers), which are more commonly used for advanced engineering prototypes and manufacturing. Those material selections that do exist are limited in their capacity for fusion due to disparate chemical and physical properties, limiting the potential mechanical range for multi-material printed composites.

Non-dependence of nuclear decay rates of I and Tc on Earth-Sun distance.

Recently published studies have suggested an annual fluctuation of the decay rate of several radionuclides, in particular Si and Ra. Variation of solar neutrino flux caused by variation of Earth-Sun distance has been proposed as the mechanism of this fluctuation. In this study we prospectively look at two radionuclides which have not previously been studied for annual variation, I and Tc.

7 Tesla 22-channel wrap-around coil array for cervical spinal cord and brainstem imaging.

Purpose: Increased signal-to-noise ratio and blood oxygenation level-dependent sensitivity at 7 Tesla (T) have the potential to enable high-resolution imaging of the human cervical spinal cord and brainstem. We propose a new two-panel radiofrequency coil design for these regions to fully exploit the advantages of ultra-high field.

Methods: A two-panel array, containing four transmit/receive and 18 receive-only elements fully encircling the head and neck, was constructed following simulations demonstrating the B1+ and specific absorption rate (SAR) benefits of two-panel over one-panel arrays.

Efficacy and safety of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. Multicenter phase III clinical trials. Efficacy of early imaging.

The efficacy of contrast-enhanced magnetic resonance imaging (MRI) for detecting and characterizing, or excluding, hepatic masses was assessed in 404 patients, following the intravenous administration of mangafodipir trisodium (MnDPDP) injection, a hepatic MRI contrast agent. An initial contrast-enhanced computed tomography (CT) examination was followed by unenhanced MRI, injection of MnDPDP (5 micromol/kg IV), and enhanced MRI at 15 minutes post injection. Agreement of the radiologic diagnoses with the patients' final diagnoses was higher for enhanced MRI and for the combined unenhanced and enhanced MRI evaluations than for unenhanced MRI alone or enhanced CT using the clinical diagnosis as the gold standard.

A prospective assessment of breath-hold fast spin echo and inversion recovery fast spin echo techniques for detection and characterization of focal hepatic lesions.

The purpose of this study was to prospectively assess two breath-hold T(2)-weighted fast spin-echo sequences and two breath-hold inversion recovery fast spin-echo sequences to determine their relative ability to detect and characterize focal hepatic lesions. Fourteen patients with a total of nineteen proven focal hepatic lesions were imaged with two breath-hold T(2)-weighted (T2W) fast spin echo sequences (HASTE TE = 66 and HASTE TE = 120), two breath-hold inversion recovery fast spin echo sequences (IRFSE TE = 64 and IRFSE TE = 95), and a nonbreath-hold T(2)-weighted fast-spin echo sequence (FSE TE = 96-120). Contrast-to-noise ratios (CNRs) were measured for all proven lesions on all sequences.

A retrospective analysis of the accuracy of T2-weighted images and dynamic gadolinium-enhanced sequences in the detection and characterization of focal hepatic lesions.

The aim of this study was to determine the relative ability of T2-weighted and dynamic gadolinium-enhanced T1-weighted gradient-echo sequences to detect and characterize focal hepatic lesions. We retrospectively studied 37 patients with proven focal hepatic lesions using the following sequences: a T1-weighted spin-echo sequence (T1), a T2-weighted sequence (T2), and a series of breath-hold dynamic gadolinium-enhanced T1-weighted gradient-echo sequences (Gd). Two observers were asked to determine retrospectively the number and type of focal hepatic lesions present using images from three combinations of sequences (T1+T2, T1+Gd, T1+T2+Gd).

Hepatic T2-weighted MRI: a prospective comparison of sequences, including breath-hold, half-Fourier turbo spin echo (HASTE).

The purpose of this study was to quantitatively compare the hepatic contrast characteristics of conventional spin-echo (CSE) and fast spin-echo (FSE) sequences with breath-hold T2-weighted images acquired with half-Fourier turbo spin echo (HASTE). Forty-five patients were examined with a phased-array surface coil. Nineteen patients had focal hepatic lesions, including eight malignant tumors, 10 cavernous hemangiomas, and one hepatic adenoma.

Renal MR angiography.

MR angiography is a noninvasive technique for evaluating blood vessels. Its main use in the renal vasculature has been for evaluating the renal arteries for stenoses and for diagnosing renal vein thrombosis. Different methods of renal MR angiography, including gadolinium-enhanced MR angiography, are described, including guidelines for their use.

Characterization of focal hepatic masses by dynamic contrast-enhanced MR imaging: findings in 311 lesions.

This study aimed to determine the overall accuracy of known enhancement patterns for the characterization of a large series of focal hepatic masses on dynamic contrast-enhanced magnetic resonance (MR) images. Breath-hold T1-weighted images of the liver acquired before intravenous gadolinium administration and serially over 6-10 min after contrast injection were acquired in < 25 a using FLASH or rapid spin-echo pulse sequences. A total of 311 proven focal hepatic masses in 128 patients were analyzed, including 192 malignant lesions (166 metastases and 26 hepatomas) and 119 benign lesions (48 cavernous hemangiomas, 45 hepatic cysts, and 26 other abnormalities).

Renal arteries: clinical comparison of three-dimensional time-of-flight MR angiographic sequences and radiographic angiography.

Purpose: To prospectively compare three magnetic resonance (MR) angiographic techniques in the renal arteries.

Materials And Methods: Twenty-five adult patients underwent three-dimensional time-of-flight MR angiography with three different sequences: conventional, tilted optimized nonsaturating excitation (TONE), and selective inversion-recovery rapid gradient-echo (SIR-RAGE). Fifteen also underwent radiographic angiography.

MR imaging of the biliary system.

MR imaging has a distinct role to play in two areas of hepatobiliary imaging that continue to challenge the radiologist--evaluation of the gallbladder and evaluation of the jaundiced patient. The distinction between primary gallbladder carcinoma and chronic cholecystitis remains a diagnostic dilemma for all cross-sectional imaging modalities. MR imaging may be useful in detection of local invasion or metastatic disease.

Large angle spin-echo imaging.

A study was undertaken to assess the use of excitation flip angles greater than 90 degrees for T1 weighted spin-echo (SE) imaging with a single 180 degrees refocusing pulse and short TR values. Theoretical predictions of signal intensity for SE images with excitation pulse angles of 90-180 degrees were calculated based on the Bloch equations and then measured experimentally from MR images of MnCl2 phantoms of various concentrations. Liver signal-to-noise ratios (SNR) and liver-spleen contrast-to-noise ratios (CNR) were measured from breathhold MR images of the upper abdomen in 16 patients using 90 and 110 degrees excitation flip angles.

Dynamic contrast-enhanced MR imaging of the liver: parenchymal enhancement patterns.

A retrospective study of 164 patients undergoing dynamic contrast-enhanced magnetic resonance (MR) imaging was performed to assess hepatic parenchymal enhancement patterns and to correlate these patterns with hepatic function and disease. Rapid T1-weighted images were acquired before and after gadolinium administration. Hepatic enhancement patterns were analyzed blindly by two observers.

MR imaging of Crohn disease: use of perflubron as a gastrointestinal contrast agent.

This study was undertaken to evaluate the use of perflubron (perfluorooctylbromide) as an oral contrast agent for magnetic resonance (MR) imaging of patients with Crohn disease. MR examinations were performed before and after perflubron administration in 12 patients with documented Crohn disease. Glucagon was administered intramuscularly before the post-perflubron examinations.

MR appearance of umbilical endometriosis.

Objective: We describe the MR appearance of endometriosis involving the umbilicus in two patients. One patient had a history of laparoscopy performed through the umbilicus; the other had an umbilical hernia.

Materials And Methods: MR imaging was performed using both a body coil and a spine coil (with the patient lying prone on the spine coil).

Pediatric knee MR imaging: pattern of injuries in the immature skeleton.

Purpose: To evaluate the frequency of various cartilaginous and ligamentous knee injuries with magnetic resonance (MR) imaging in a large pediatric population.

Materials And Methods: The authors reviewed 104 consecutive MR imaging studies acquired in patients 4-18 years of age with open physes. Frequency of various injuries was compared by using a chi 2 test.

Differentiation of hepatomas from nonhepatomatous masses: use of MnDPDP-enhanced MR images.

Manganese (II) N,N'-dipyridoxylethylenediamine-N,N' diacetate 5,5'-bis(phosphate) (MnDPDP) is a hepatobiliary agent that is incorporated into the hepatocyte. We retrospectively reviewed our experience with 39 focal liver lesions in 20 patients studies with MnDPDP-enhanced hepatic magnetic resonance (MR) imaging to determine whether hepatocellular carcinoma (HCC) could be differentiated from tumors of nonhepatocyte origin (metastases, cavernous hemangiomas, etc.) For all cases, liver parenchyma enhanced significantly following MnDPDP administration.

Chemical shift misregistration artifact: increased conspicuity following intravenous administration of gadopentetate dimeglumine.

We have observed increased conspicuity of chemical shift misregistration artifact (CSMA) associated with enhancing structures on MR images after the intravenous administration of gadopentetate dimeglumine compared with corresponding unenhanced images. In this study, we investigate the influence of gadopentetate dimeglumine administration on the conspicuity of CSMA in MR imaging of the kidneys. Nine gadopentetate-enhanced and unenhanced T1-weighted images of the kidneys were evaluated in a side-by-side fashion for the conspicuity of both the high and low signal intensity (SI) components of CSMA.

Regional phase correction of inversion-recovery MR images.

Many MR imaging systems are limited in their ability to successfully display inversion-recovery images. The reason is that part of the contrast is encoded as phase differences between pixels, whereas in the more commonly used spin-echo pulse sequence all the information is contained in the pixel magnitude. Inversion-recovery images are often displayed in magnitude form, resulting in loss of potentially useful phase information contained in the data.