Radiology Research and Practice最新文献

Background: Work-related lower back pain (WrLBP) is a global health issue and a rising concern in the State of Kuwait. The prevalence and the risk factors of WrLBP among radiographers are not well documented.

Objective: The purpose of the study was to determine the one-year prevalence, characteristics, impact, and physical risk factors of WrLBP among radiographers in the State of Kuwait.

Methods: A self-administered questionnaire was distributed to 200 radiographers. The questionnaire collected data on demographics, physical risk factors, and the occurrence of WrLBP in the previous 12 months. Descriptive statistics, frequency calculations, and chi-square analyses were performed.

Results: One hundred forty-six radiographers completed and returned the questionnaires with a response rate of 73% (146/200). The one-year prevalence of WrLBP was 16%. The prevalence of WrLBP was not significantly associated with the participants' demographics. Although WrLBP was significantly associated with work demands, the overall impact of WrLBP on work duties was minimal.

Conclusions: The occurrence of WrLBP among radiographers in Kuwait was low, particularly when compared to healthcare providers involved in more patient handling and direct contact. However, various physical risk factors were identified. Further research is needed to investigate the effect of a treatment and prevention program on the prevalence of WrLBP.

Quantitative Susceptibility Mapping (QSM) is an MRI tool with the potential to reveal pathological changes from magnetic susceptibility measurements. Before phase data can be used to recover susceptibility (Δχ), the QSM process begins with two steps: data acquisition and phase estimation. We assess the performance of these steps, when applied without user intervention, on several variations of a phantom imaging task. We used a rotating-tube phantom with five tubes ranging from Δχ=0.05 ppm to Δχ=0.336 ppm. MRI data was acquired at nine angles of rotation for four different pulse sequences. The images were processed by 10 phase estimation algorithms including Laplacian, region-growing, branch-cut, temporal unwrapping, and maximum-likelihood methods, resulting in approximately 90 different combinations of data acquisition and phase estimation methods. We analyzed errors between measured and expected phases using the probability mass function and Cumulative Distribution Function. Repeatable acquisition and estimation methods were identified based on the probability of relative phase errors. For single-echo GRE and segmented EPI sequences, a region-growing method was most reliable with Pr (relative error <0.1) = 0.95 and 0.90, respectively. For multiecho sequences, a maximum-likelihood method was most reliable with Pr (relative error <0.1) = 0.97. The most repeatable multiecho methods outperformed the most repeatable single-echo methods. We found a wide range of repeatability and reproducibility for off-the-shelf MRI acquisition and phase estimation approaches, and this variability may prevent the techniques from being widely integrated in clinical workflows. The error was dominated in many cases by spatially discontinuous phase unwrapping errors. Any postprocessing applied on erroneous phase estimates, such as QSM's background field removal and dipole inversion, would suffer from error propagation. Our paradigm identifies methods that yield consistent and accurate phase estimates that would ultimately yield consistent and accurate Δχ estimates.

Introduction: This manuscript aims to investigate the amount of intraluminal gas in acute, nonperforated appendicitis identified on computed tomography (CT) in diagnosing gangrenous appendicitis.

Methods: This is a retrospective observational, case-control study with consecutive data collected at a tertiary institution over a two-year period, of patients with CT-diagnosed acute appendicitis who subsequently went on for surgery within 48 hours. Patients who were less than 16 years old, who had an interval between CT and surgery of more than 48 hours, or with CT evidence of appendiceal perforation were excluded. Images were independently assessed by 3 radiologists for intraluminal gas, and the results were then correlated with reference standards obtained from surgical and histopathology reports for the diagnosis of nongangrenous versus gangrenous appendicitis. The sensitivity, specificity, and predictive values of CT intraluminal gas in gangrenous appendicitis were calculated.

Results: Our study identified 93 patients with nonperforated acute appendicitis who underwent surgery within the stated timeframe. Intraluminal gas in the appendix was identified in 26 patients (28%), of which 54% had macroscopic and/or microscopic evidence of gangrenous appendicitis. This is in contrast to the subgroup of patients who did not have intraluminal gas (72%), of which only 33% had gangrenous appendicitis. The specificity of intraluminal gas for gangrenous appendicitis is 79%, with a negative predictive value of 86% and likelihood ratio of 1.85.

Conclusion: In cases of established acute appendicitis, the presence of intraluminal gas is a moderately specific sign for gangrenous complication. This is worth reporting as it can help prognosticate and triage patients accordingly, for a timelier surgical management and a better outcome.