Citations

Background and Aims: Reducing avoidable readmissions in cirrhosis is challenging. Enhanced engagement using health information technology (HIT) interventions and caregivers lowered readmissions in an open-label study of the Patient Buddy App (PBA). Aim : Multicenter trial of PBA versus standard of care (SOC) to reduce avoidable readmissions. Approach and Results: An open-label, randomized clinical trial was performed at 3 sites to study the effect of PBA (HIT) versus SOC in cirrhosis inpatients with adult caregivers (dyads). Initial randomization was 1:1:1 between SOC, HIT only, and HIT+ visits. However, due to COVID-19, an unplanned study redesign required a combined HIT versus SOC. Primary outcome : Avoidable readmissions (decided by a blinded monitoring board). Secondary outcomes were all-cause readmission and stakeholder input. PBA focused on medication adherence, cognitive testing, and symptoms, and was remotely monitored by study staff. In all, 464 subjects (232 dyads) were enrolled [Virginia Commonwealth University (VCU): 120, Mayo: 40, Department of Veterans Affairs (VA): 72; 116 dyads/group]. Avoidable readmissions were significantly higher in SOC versus HIT (19.8% vs. 10.3%, p =0.04) with OR of 2.14 (95% CI 1.01–4.54) and remained significant even after removing pre-COVID HIT+ visits patients (19.8% vs. 9.3%, p =0.040) with OR of 2.41 (95% CI 1.02–5.69). All-cause readmissions were higher in SOC versus HIT (48% vs. 30%, p =0.005). App evaluation/engagemen t : 1660 alerts were sent; mostly related to HE. Most dyads were satisfied with the app. Conclusions: In a multicenter randomized clinical trial of 464 cirrhosis inpatients and their CGs across several practice settings, the PBA was associated with lower avoidable readmissions at 30 days post-discharge compared to SOC.

Extremely severe nausea was experienced by four subjects positioned prone on a 7T scanner table with their arm extended overhead for a wrist examination and their head positioned approximately 10–20 cm above the magnet's central axis. Movement through the large static and spatial field gradients of current 7T MRI scanner magnets typically causes mild vestibular activation which is well tolerated by most individuals. However, when positioned off‐axis, the head moves through regions of even larger and more rapidly changing magnetic fields which in the current study were sufficient to induce the extremely severe nausea. Ensuring the head remains on‐axis mitigates this effect.

Lactulose-based hepatic encephalopathy treatment requires bowel movements/day titration, which is improved with Bristol stool scale (BSS) incorporation. Dieta app evaluates artificial intelligence (AI)-based BSS (AI-BSS) with stool images. Initially, controls (N = 13) and cirrhosis patients on lactulose/not on lactulose (n = 33) were trained on the app. They entered self-reported BSS (self-BSS) with AI-BSS communicated. Lactulose dose changes were tracked. A subset (n = 12) was retested with AI communication blocked. Most subjects were comfortable with the app. Self/AI-BSS and lactulose dose/AI-BSS correlation increased with app use. AI-BSS communications improved insight into self-BSS over time. Dieta app to gauge stool AI characteristics was acceptable and increased insight into lactulose dose and BSS in cirrhosis.

AbstractBackgroundThe imaging of patients with implanted electrically‐conductive devices via magnetic resonance imaging at ultra‐high fields is hampered by uncertainties relating to the potential for inducing tissue heating adjacent to the implant due to coupling of energy from the incident electromagnetic field into the implant. Existing data in the peer‐reviewed literature of comparisons across field strengths of tissue heating and its surrogate, the specific absorption rate (SAR), is scarce and contradictory, leading to further doubts pertaining to the safety of imaging patients with such devices.PurposeThe radiofrequency‐induced SAR adjacent to orthopedic screws of varying length and at frequencies of 64 to 498 MHz was investigated via full‐wave electromagnetic simulations, to provide an accurate comparison of SAR across MRI field strengths.MethodsDipole antennas were used for RF transmission to achieve a uniform electric field tangential to the screws located 120 mm above the antenna midpoints, embedded in a bone‐mimicking material. The input power to the antennas was constrained to achieve the following targets without the screw present: (i) E = 100 V/m, (ii) B1+ = 2 μT, and (iii) global‐average‐SAR = 3.2 W/kg. Simulations were performed with a spatial resolution of 0.2 mm in the volume surrounding the screws, resulting in 76–137 MCells, noting the maximum 1 g‐averaged SAR value in each case. Simulations were repeated at 128 and 297 MHz for screws embedded in muscle tissue.ResultsThe peak SAR, occurring at the resonant screw length, substantially increased as the frequency decreased when the input power to the dipole antenna was constrained to achieve constant electric field in background tissue at the screws’ locations. A similar pattern was observed when constraining input power to achieve constant B1+ and global‐average‐SAR. The dielectric properties of the tissue in which the screws were embedded dominated the SAR comparisons between 297 and 128 MHz.ConclusionsThe study design allowed for a direct comparison to be performed of SAR across frequencies and implant lengths without the confounding effect of variable incident electric field. Lower frequencies produced substantially larger SAR values for implants approaching the resonant length for the worst‐case uniform incident electric field along the screws’ length. The data may inform risk‐benefit assessments for imaging patients with orthopedic implants at the new clinical field strength of 7 Tesla.

AbstractPurposeDental amalgam contains mercury and is commonly used in dental restorations. The impact of MRI on mercury excretion from dental amalgam is not well understood across clinical field strengths, especially 7T. We investigated the effects of MRI exposure on mercury excretion using fresh, lab‐created dental amalgam restorations and in extracted teeth with old, pre‐existing restorations.MethodsDonated, unfilled human teeth (n = 120) were restored with amalgam before being stored in saline, artificial saliva, or a dry box prior to MRI scanning. The teeth were placed in individual tubes of fresh artificial saliva and scanned at 1.5T, 3T, or 7T or left unscanned as controls. Mercury concentrations were measured 24–30 h later. Donated teeth with pre‐existing restorations (n = 40) were stored in artificial saliva, scanned at 7T or left unscanned as controls, and mercury concentration tested.ResultsFor teeth extracted and restored in a laboratory, no significant difference was found (F = 2.42, P = 0.072) between mean mercury concentrations of unscanned teeth (13.72 μg/L) and teeth scanned at 1.5T (10.88 μg/L), 3T (12.65 μg/L), or 7T (8.88 μg/L). For teeth extracted with previously placed restorations, no significant difference (P = 0.288) was found between unscanned controls (4.28 μg/L) and teeth scanned at 7T (6.63 μg/L).ConclusionMRI of dental amalgam does not significantly increase mercury excretion at 1.5T, 3T, or 7T compared to unscanned teeth. This holds true for controlled laboratory restorations as well as for those placed and lived with prior to extraction and scanning, demonstrating no added risk to the clinical patient or research subject.

Cardiovascular pathology is the leading cause of death and disability in the Western world, and current diagnostic testing usually evaluates the anatomy of the vessel to determine if the vessel contains blockages and plaques. However, there is a growing school of thought that other measures, such as wall shear stress, provide more useful information for earlier diagnosis and prediction of atherosclerotic related disease compared to pulsed-wave Doppler ultrasound, magnetic resonance angiography, or computed tomography angiography. A novel algorithm for quantifying wall shear stress (WSS) in atherosclerotic plaque using diagnostic ultrasound imaging, called Multifrequency ultrafast Doppler spectral analysis (MFUDSA), is presented. The development of this algorithm is presented, in addition to its optimisation using simulation studies and in-vitro experiments with flow phantoms approximating the early stages of cardiovascular disease. The presented algorithm is compared with commonly used WSS assessment methods, such as standard PW Doppler, Ultrafast Doppler, and Parabolic Doppler, as well as plane-wave Doppler. Compared to an equivalent processing architecture with one-dimensional Fourier analysis, the MFUDSA algorithm provided an increase in signal-to-noise ratio (SNR) by a factor of 4–8 and an increase in velocity resolution by a factor of 1.10–1.35. The results indicated that MFUDSA outperformed the others, with significant differences detected between the typical WSS values of moderate disease progression (p = 0.003) and severe disease progression (p = 0.001). The algorithm demonstrated an improved performance for the assessment of WSS and has potential to provide an earlier diagnosis of cardiovascular disease than current techniques allow.