Canadian Association of Radiologists Journal-Journal De L Association Canadienne Des Radiologistes最新文献

Purpose: Accurate vessel measurement is essential in endovascular thrombectomy (EVT) for acute ischemic stroke. Discrepancies between computed tomography angiography (CTA) and digital subtraction angiography (DSA) may impact procedural planning and device selection. This study compares vessel diameter measurements from CTA and DSA in patients with middle cerebral artery (MCA) M1 occlusions.

Methods: In this single-center retrospective study, 90 consecutive patients who underwent EVT for MCA M1 occlusions between February 2020 and March 2024 were included. Vessel diameters were independently measured by 3 neuroradiologists using CTA and DSA (pre- and post-intervention). Statistical analysis included Wilcoxon signed-rank tests, intraclass correlation coefficient (ICC), and Bland-Altman analysis.

Results: CTA consistently overestimated vessel diameter compared to DSA. The mean M1 diameter was 2.29 ± 0.27 mm on CTA and 2.16 ± 0.30 mm on pre-EVT DSA (P < .001), with a median difference of 0.4 mm (IQR: 0.2-0.6 mm). In 70% of cases, CTA values exceeded DSA. Bland-Altman analysis confirmed a mean difference of +0.13 mm (limits of agreement: -0.25 to +0.51 mm). No significant change was observed between pre- and post-EVT DSA measurements (P = .103). Clot-side M1 segments were significantly smaller than contralateral measurements on CTA (P = .003). Inter-rater agreement was good (ICC = .785).

Conclusions: CTA overestimates MCA M1 diameter relative to DSA. While the discrepancy is modest, it may influence device selection in borderline cases. Awareness of this variability is important, and further research is warranted to explore its clinical implications.

Theranostic represents a transformative approach in precision medicine, integrating diagnostic imaging with targeted radiopharmaceutical therapy to enhance individualized disease management. Rooted in nuclear medicine, this approach uses molecular targeting agents labelled with diagnostic radioisotopes for imaging and therapeutic radioisotopes for treatment, ensuring a seamless transition from diagnosis to therapy. The field has evolved significantly in the last decade, with prostate-specific membrane antigen (PSMA)-targeted radioligand therapy transforming prostate cancer patient management and somatostatin receptor (SSTR)-targeted agents revolutionizing neuroendocrine tumour (NET) treatment. Considering its interdisciplinary nature, collaboration between nuclear medicine specialists, oncologists, radiologists, and other healthcare professionals is critical to refining clinical applications and improving patient outcomes. As prominent members of the theranostic team, radiologists play a pivotal role, from patient selection and imaging-based eligibility assessment to response evaluation and long-term monitoring. In this regard, advanced imaging modalities facilitate the precise evaluation of disease characteristics, guiding treatment decisions. Hence, as theranostics becomes increasingly integrated into patient management, radiologists face the need to be well-versed in both the technical aspects and clinical implications. In this review, we aimed to provide a primer for radiologists to gain a general insight into the theranostic field and its basic principles.

The Canadian Association of Radiologists (CAR) metabolic dysfunction-associated steatotic liver disease (MASLD) Working Group (WG) is a multidisciplinary working group composed of radiologists, hepatologists, and family physicians. In this 3-part series, we provide Delphi consensus-based guidance on clinical and imaging findings for patients with known or suspected MASLD (formerly termed nonalcoholic fatty liver disease or NAFLD). Part 1 focuses on the detection and grading of hepatic steatosis on imaging; Part 2 on risk-stratification of patients with MASLD, including a patient pathway using serological and imaging investigations; and Part 3 on the implementation of practice recommendations for quality assurance using shear wave elastography (SWE) and magnetic resonance elastography (MRE) programs. In Part 2 of these guidelines, the WG provides 14 recommendations for risk stratifying MASLD patients into low and high risk for advanced hepatic fibrosis (F ≥ 3) using a combination of serological and imaging investigations. Population screening and risk stratification of MASLD patients using a clinical and serological investigation (FIB-4) followed by imaging pathway is recommended. Clinical, technical, and grading recommendations for point shear wave elastography (pSWE), 2-dimensional SWE (2D-SWE), and MRE are discussed.

Waiting times for medical imaging examinations in Canada are growing as the demand for these tests exceeds current capacity. This document summarizes strategies that may be employed to increase medical imaging patient throughput in an environment of limited resources. This document also advocates for provincial measures to optimize use of resources and national policies that support sustainable radiology services to meet growing demand now and in the future.

Purpose: In pelvic MRI, Turbo Spin Echo (TSE) pulse sequences are used for T2-weighted imaging. However, its lengthy acquisition time increases the potential for artifacts. Deep learning (DL) reconstruction achieves reduced scan times without the degradation in image quality associated with other accelerated techniques. Unfortunately, a comprehensive assessment of DL-reconstruction in pelvic MRI has not been performed. The objective of this prospective study was to compare the performance of DL-TSE and conventional TSE pulse sequences in a broad spectrum of pelvic MRI indications.

Methods: Fifty-five subjects (33 females and 22 males) were scanned at 3 T using DL-TSE and conventional TSE sequences in axial and/or oblique acquisition planes. Two radiologists independently assessed image quality in 6 categories: edge definition, vessel margin sharpness, T2 Contrast Dynamic Range, artifacts, overall image quality, and lesion features. The contrast ratio was calculated for quantitative assessment. A two-tailed sign test was used for assessment.

Results: The 2 readers found DL-TSE to deliver equal or superior image quality than conventional TSE in most cases. There were only 3 instances out of 24 where conventional TSE was scored as providing better image quality. Readers agreed on DL-TSE superiority/inferiority/equivalence in 67% of categories in the axial plane and 75% in the oblique plane. DL-TSE also demonstrated a better contrast ratio in 75% of cases. DL-TSE reduced scan time by approximately 50%.

Conclusion: DL-accelerated TSE sequences generally provide equal or better image quality in pelvic MRI than standard TSE with significantly reduced acquisition times.