Acta radiologica open最新文献

Extramedullary involvement of multiple myeloma is an uncommon and aggressive condition characterized by proliferation of monoclonal plasma cells located outside the bone marrow. This report describes the imaging findings of a patient who presented with continuous soft-tissue disease on the ribs, suspected as extrapleural space tumors on chest CT. The patient was diagnosed with multiple myeloma through surgical biopsy of the tumor and bone marrow.

Background: Fetal ultrasound has limitations, especially if the patient is obese or in cases with oligohydramnios. Magnetic resonance imaging (MRI) can then be used as a complement, but only few studies have focused on examinations in the second trimester.

Purpose: To validate MRI as a complement to diagnose fetal anomalies in the second trimester.

Material and methods: This retrospective study retrieved data from January 2008 to July 2012 from the Fetal Medicine Unit and Department of Radiology at Uppsala University Hospital. Ultrasound and MRI findings were reviewed in 121 fetuses in relation to the final diagnosis, including postpartum follow-up and autopsy results.

Results: Of the 121 fetuses, 51 (42%) had a CNS anomaly and 70 (58%) a non-CNS anomaly diagnosed or suspected. MRI provided additional information in 21% of all cases without changing the management and revealed information that changed the management of the pregnancy in 13%. When a CNS anomaly was detected or suspected, the MRI provided additional information in 22% and changed the management in 10%. The corresponding figures for non-CNS cases were 21% and 16%, respectively. The proportion of cases with additional information that changed the management was especially high in patients with a BMI >30 kg/m² (25%) and in patients with oligohydramnios (38%). In five cases in category III, false-positive ultrasound findings were identified.

Conclusions: MRI in the second trimester complements ultrasound and improves diagnosis of fetal CNS- and non-CNS anomalies especially when oligohydramnios or maternal obesity is present.

Background: Uterine cavity pathology may affect the endometrium or myometrium, resulting in distortion of the uterine cavity, and is responsible for 2%-5% of infertility. The methods for its assessment usually involve imaging modalities like pelvic ultrasonography, often transvaginal-(TVS), and hysterosalpingography-(HSG), with hysteroscopy-(HSC) as the gold standard. However, HSC is not readily available in resource-poor-settings.

Purpose: To determine and compare the diagnostic accuracy of TVS and HSG in detecting uterine cavity pathology using HSC as a gold standard.

Materials and methods: A cross-sectional analytical study of consenting infertile women for evaluation of the uterine cavity using transvaginal-ultrasonography, hysterosalpingogram, and hysteroscopy. The primary-outcome-measures were the sensitivity, specificity, and accuracy of TVS and HSG in detecting uterine cavity abnormalities using HSG as the gold standard.

Results: Eighty-eight participants were analysed for this study. The lesions confirmed on HSC were intrauterine-adhesions (43.1%), endometrial polyps (14.8%), submucous fibroids (18.2%), intrauterine-septum (13.6%), and cavity distortion (14.8%). The overall sensitivity with TVS was 57.7%, with a specificity of 97.6%, a positive-predictive-value (PPV) of 88.2%, and a negative-predictive-value (NPV) of 88.2%, giving a percentage-accuracy of 88.2%. In comparison, HSG had a sensitivity of 72.1%, a specificity of 99.4%, a PPV of 97.4%, and an NPV of 92.0%, giving an overall accuracy of 92.9%. The detection rates of TVS and HSG in this category were: fibroids (97.7% vs 89.8%; p = .0004) and adhesions (73.9% vs 87.5%; p = .0002), respectively.

Conclusion: HSG appears to be the superior modality for detection of obliterative uterine cavity pathologies, while TVS is better suited for myometrium and endometrial lesions.

Background: Diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are widely used in the orofacial region. Furthermore, quantitative analyses have proven useful. However, a few reports have described the correlation between DWI-derived parameters and DCE-MRI-derived parameters, and the results have been controversial.

Purpose: To evaluate the correlation among parameters obtained by DWI and DCE-MRI and to compare them between benign and malignant lesions.

Material and methods: Fifty orofacial lesions were analysed. The apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudodiffusion coefficient (D*) and perfusion fraction (f) were estimated by DWI. For DCE-MRI, TK model analysis was performed to estimate physiological parameters, for example, the influx forward volume transfer constant into the extracellular-extravascular space (EES) (K^trans) and fractional volumes of EES and plasma components (ve and vp).

Results: Both ADC and D showed a moderate positive correlation with ve (ρ = 0.640 and 0.645, respectively). K^trans showed a marginally weak correlation with f (ρ = 0.296), while vp was not correlated with f or D*; therefore, IVIM perfusion-related parameters and TK model perfusion-related parameters were not straightforward. Both D and ve yielded high diagnostic power between benign lesions and malignant tumours with areas under the curve (AUCs) of 0.830 and 0.782, respectively.

Conclusion: Both D and ve were reliable parameters that were useful for the differential diagnosis. In addition, the true diffusion coefficient (D) was affected by the fractional volume of EES.

⁶⁸Gallium-PSMA positron emission tomography/computer tomography has been utilized recently for the diagnosis and staging of prostate cancer. PSMA is a transmembrane protein that is expressed not only in the prostate gland but also in other tissues. While some pitfalls have been addressed, there are still uncertainties. Herein, we report a 79-year-old male with prostate cancer who underwent a PSMA scan after coronary artery bypass graft surgery, revealing disease progression and PSMA-avid foci at the surgical stitch sites. This report discusses the immunohistochemical and molecular imaging mechanisms underlying PSMA expression in surgical scar tissues, providing critical insights for optimizing radiologic reporting in such situations.

Background: Low-dose CT (LDCT) chest protocols have widespread clinical applications for many indications; as a result, there is a need for protocol assessment prior to standardization. Dalhousie University and Oslo Metropolitan University have a formally established cooperative relationship.

Purpose: The purpose is to assess radiation dose and image quality for LDCT chest protocols in seven different hospital locations in Norway and Canada.

Material and methods: Retrospective dosimetry data, volumetric CT dose index (CTDI_vol), and dose length product (DLP) from 240 average-sized patients as well as CT protocol parameters were included in the survey. Effective dose (ED) and size-specific dose estimate (SSDE) were calculated for each examination. For a quantitative image quality analysis, noise, CT number, and signal-to-noise ratio (SNR) were determined for three regions in the chest. The contrast-to-noise ratio (CNR) was calculated for lung parenchyma in comparison to the subcutaneous fat. Differences in dose and image quality were evaluated by a single-factor ANOVA test. A two-sample t-test was performed to determine differences in means between individual scanners.

Results: The ANOVA test revealed significant differences (p < .05) in dose values for all scanners, including identical scanner models. Statistically significant differences (p < .05) were determined in mean values of the SNR distributions between the scanners in all three measured regions in the chest, as well as the CNR values.

Conclusion: The observed variations in dose and image quality measurements, even within the same hospitals and between identical scanner models, indicate a potential for protocol optimization in the involved hospitals in both countries.