Purpose: To describe approaches for determining optimal spatial and temporal resolutions for the proton resonance frequency shift method of quantitative magnetic resonance temperature imaging (MRTI) guidance of transurethral ultrasonic prostate ablation.

Materials And Methods: Temperature distributions of two transurethral ultrasound applicators (90 degrees sectored tubular and planar arrays) for canine prostate ablation were measured via MRTI during in vivo sonication, and agree well with two-dimensional finite difference model simulations at various spatial resolutions. Measured temperature distributions establish the relevant signal-to-noise ratio (SNR) range for thermometry in an interventional MR scanner, and are reconstructed at different resolutions to compare resultant temperature measurements. Various temporal resolutions are calculated by averaging MRTI frames.

Results: When noise is added to simulated temperature distributions for tubular and planar applicators, the minimum root mean squared (RMS) error is achieved by reconstructing to pixel sizes of 1.9 and 1.7 mm, respectively. In in vivo measurements, low spatial resolution MRTI data are shown to reduce the noise without significantly affecting thermal dose calculations. Temporal resolution of 0.66 frames/minute leads to measurement errors of more than 12 degrees C during rapid heating.

Conclusion: Optimizing MRTI pixel size entails balancing large pixel SNR gain with accuracy in representing underlying temperature distributions.

Download full-text PDF

Source
http://dx.doi.org/10.1002/jmri.20339DOI Listing

Publication Analysis

Top Keywords

temperature distributions
16
spatial temporal
8
temporal resolution
8
transurethral ultrasound
8
temporal resolutions
8
tubular planar
8
temperature
6
mrti
5
effects spatial
4
temporal
4

Similar Publications

Assessing the distribution pattern of Saussurea medusa under climate change using an optimized MaxEnt model in Qinghai-Xizang Plateau.

Environ Monit Assess

January 2025

Qinghai Provincial Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai, China.

Saussurea medusa is a rare alpine plant with significant medicinal value. To better understand the changes in its habitat in the context of climate change, this study used an optimized MaxEnt model to predict the current and future habitat of S. medusa under four shared socioeconomic pathways (SSPs) across three time periods (current, mid-century, and end-century) based on three climate system models.

View Article and Find Full Text PDF

Species distribution modeling is extensively used for predicting potential distributions of invasive species. However, an ensemble modeling approach has been less frequently used particularly pest species. The bird cherry-oat aphid Rhopalosiphum padi L.

View Article and Find Full Text PDF

Deep oil reservoirs are becoming increasingly significant fields of hydrocarbon exploration in recent decades. Hydrothermal fluid flow is deemed as a potentially crucial factor affecting the occurrence of deep oil reservoirs, such as enhancing porosity/permeability of reservoirs, accelerating oil generation and thermal cracking, and modifying organic properties of crude oils. Understanding the interplay between hydrothermal fluids and crude oils would provide useful constraints for reconstructing hydrocarbon accumulation processes and predicting the distribution patterns of crude oils.

View Article and Find Full Text PDF

Bidirectional effect modifications of temperature and PM on myocardial infarction morbidity and mortality in Beijing, China from 2007 to 2021.

Ecotoxicol Environ Saf

January 2025

Center for Clinical and Epidemiologic Research, Beijing An Zhen Hospital, Capital Medical University, Beijing, China; Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing, China; National Clinical Research Center of Cardiovascular Diseases, Beijing, China; The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China; The Beijing Municipal Key Laboratory of Clinical Epidemiology, Beijing, China. Electronic address:

Background: Ambient temperatures and PM can trigger myocardial infarction (MI), while little is known about the complex interplay between these two factors on MI, especially morbidity.

Objectives: To investigate bidirectional effect modifications of temperature and PM on MI morbidity and mortality.

Methods: A time-stratified case-crossover study was conducted utilizing high-resolution data of temperature and PM, along with 498,077 MI cases from the citywide registry in Beijing, China from 2007 to 2021.

View Article and Find Full Text PDF

A few Aspergillus section Nigri species are involved in the ochratoxin A (OTA) contamination in grapes worldwide, and its occurrence is determined by the agro-climatic conditions of each region. The aim of this study was to examine the diversity of black aspergilli isolated from grapes, soil, and air from vineyards with different agro-climatic conditions. A total of four vineyards located in Catalonia were studied.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!