ACTA Radiologica (Test)

Acta Radiologica, Ahead of Print. <br/>BackgroundGiving contrast material before 1H-magnetic resonance spectroscopy (MRS) could enhance the precision of locating the lesion of interest. However, evidence indicates that contrast material might influence the outcomes of MRS.PurposeTo verify the effect of gadolinium-based contrast agent (GBCA) on MRS in normal white matter.Material and MethodsA total of 34 patients were referred for brain magnetic resonance imaging (MRI) with GBCAs, and they underwent single-volume MRS before and after administering contrast material. Those patients had the MRS voxel placed at the right frontal normal white matter, which remained consistent across all examinations. Measurements were taken for the integral concerning N-acetyl aspartate (NAA), choline (Cho), creatine (Cr and Cr2), and myo-inositol (Ins) in all examinations.ResultsNAA (P = 0.0313) and Cho (P = 0.0094) had a significant decrease in their integral after intravenous GBCA administration. No significant differences were found between the pre- and post-contrast MRS studies for Cr, Cr2, and Ins.ConclusionIntravenous GBCA can alter NAA and Cho integrals in normal white matter. Therefore, brain 1H-MRS should precede intravenous GBCA administration to avoid the potential impact of contrast material on peak integrals.

Acta Radiologica, Ahead of Print. <br/>BackgroundIn this prospective study, we evaluated whether a sufficient number of glomeruli were achieved using the 8× magnification of smartphone cameras.PurposeTo increase the percutaneous ultrasound-guided renal biopsy (PURB) diagnostic value with a method that has not been tried before and reduce the need for repetition of the procedure.Material and MethodsA total of 39 adult patients who underwent PURB were included in our study. After the PURB was applied to the patients, the biopsy specimen was placed on the previously prepared sterile gauze. At this stage, 8× magnification photos were taken of the biopsy samples using the smartphone camera. The glomeruli in the photograph were counted and recorded and compared with the number of glomeruli seen at the end of the histopathological examination.ResultsThe mean number of glomeruli in the evaluated samples was counted as 6 ± 2.2 (range = 1–10) in the 8× magnification photograph. The mean number of glomeruli detected in the histopathological examination of these samples was 11 ± 5.7 (range = 2–30). A pathological glomeruli count of 10 was associated with more than five brown spots in the 8× magnification photograph (area under the curve = 0.977, P=0.0001).ConclusionTo obtain more than 10 glomeruli in a PURB specimen, five or more brownish-red dots should be counted on the 8x magnification photograph. Using smartphones as an alternative tool for evaluating renal biopsy tissue adequacy can be practical and advantageous in terms of time and labor.

Acta Radiologica, Ahead of Print. <br/>BackgroundThe etiology of medial-sided talar osteochondral lesions (OCLs) remains insufficiently understood.PurposeTo identify anatomical risk factors contributing to the development of unilateral or bilateral OCL of the talus on the medial side, utilizing morphological parameters derived from magnetic resonance imaging (MRI).Material and MethodsIn this retrospective study, 24 ankle MRI scans from 12 patients exhibiting bilateral OCLs of the talar dome on the medial side, 24 ankle MRIs from 24 patients with unilateral medial-sided OCLs, and 24 healthy controls matched for age, sex, and side within each group were analyzed. Six distinct MRI parameters were measured: the anterior opening angle of the talus (AOT); tibial axis-medial malleolus angle (TMM); plafond-malleolar angle (PMA); anterior talofibular ligament-posterior talofibular ligament (ATFL-PTFL) angle; the ratio of the distal tibial articular surface to the length of the trochlea tali arc (TAS/TAL); and the depth of the incisura fibularis (IncDep).ResultsThe AOT, ATFL-PTFL angle, and TMM of individuals in both the bilateral and unilateral groups were significantly higher when compared to the healthy controls. In addition, TMM measurements in the unilateral group were significantly higher than in the bilateral group.ConclusionAOT and TMM appeared to be the primary predisposing factors in the development of both unilateral and bilateral OCLs. Furthermore, TMM shows a greater increase in unilateral OCL cases compared to bilateral OCL cases. The fact that TMM is not significantly high in known unilateral OCL cases can be a stimulus for investigating the other ankle for OCL.

Acta Radiologica, Ahead of Print. <br/>BackgroundAngioJet rheolytic thrombectomy is associated with a higher risk of acute kidney injury due to its potential for inducing mechanical harm and intravascular hemolysis. However, previous studies have focused on a single disease entity.PurposeTo identify predictors associated with acute kidney injury after AngioJet rheolytic thrombectomy across a range of disease entities.Material and MethodsA total of 95 patients who underwent AngioJet rheolytic thrombectomy between October 2018 and April 2023 were retrospectively reviewed. In total, 11 patients were excluded due to the absence of a postprocedural serum creatinine test within 72 h; finally, 84 patients were included. Acute kidney injury was defined as a ≥1.5-fold increase or ≥0.3 mg/dL rise in serum creatinine within 72 h after the procedure. Univariate and multivariate analysis were performed to identify risk factors for acute kidney injury.ResultsTechnical and clinical success were achieved in all patients (84/84, 100%). Of the 84 patients (40 men [47.6%], 44 women [52.4%]; mean age = 67.2 ± 15.9 years), 15 (17.8%) had developed acute kidney injury. Multivariate analysis showed concurrent malignancy (odds ratio [OR] = 42.231, 95% confidence interval [CI] = 2.332–764.693; P = 0.011) and AngioJet rheolytic thrombectomy in arterial system (OR = 24.109, 95% CI = 1.319–440.551; P = 0.032) as statistically significant predictors of acute kidney injury.ConclusionsAngioJet rheolytic thrombectomy is a potential risk for acute kidney injury. Concurrent malignancy and AngioJet rheolytic thrombectomy in the arterial system are independent predictors of acute kidney injury.

Acta Radiologica, Ahead of Print. <br/>BackgroundRadiomics and deep learning (DL) can individually and efficiently identify the pathological type of brain metastases (BMs).PurposeTo investigate the feasibility of utilizing multi-parametric MRI-based deep transfer learning radiomics (DTLR) for the classification of lung adenocarcinoma (LUAD) and non-LUAD BMs.Material and MethodsA retrospective analysis was performed on 342 patients with 1389 BMs. These instances were randomly assigned to a training set of 273 (1179 BMs) and a testing set of 69 (210 BMs) in an 8:2 ratio. Eight machine learning algorithms were employed to construct the radiomics models. A DL model was developed using four pre-trained convolutional neural networks (CNNs). The DTLR model was formulated by integrating the optimal performing radiomics model and the DL model using a classification probability averaging approach. The area under the curve (AUC), calibration curve, and decision curve analysis (DCA) were utilized to assess the performance and clinical utility of the models.ResultsThe AUC for the optimal radiomics and DL model in the testing set were 0.824 (95% confidence interval [CI]= 0.726–0.923) and 0.775 (95% CI=0.666–0.884), respectively. The DTLR model demonstrated superior discriminatory power, achieving an AUC of 0.880 (95% CI=0.803–0.957). In addition, the DTLR model exhibited good consistency between actual and predicted probabilities based on the calibration curve and DCA analysis, indicating its significant clinical value.ConclusionOur study's DTLR model demonstrated high diagnostic accuracy in distinguishing LUAD from non-LUAD BMs. This method shows potential for the non-invasive identification of the histological subtype of BMs.

Acta Radiologica, Ahead of Print. <br/>BackgroundThe Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is a semi-quantitative tool for evaluating the extent and distribution of early ischemic changes.PurposeTo assess the value of ASPECTS on non-contrast CT (NCCT), arterial-phase CT (APCT), or venous-phase CT (VPCT) in predicting the final infarct core (IC) on follow-up diffusion-weighted imaging (DWI) and the clinical outcomes of patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT).Material and MethodsIn total, 120 patients with AIS who underwent EVT in our center were retrospectively enrolled. Correlations between CT-ASPECTS and follow-up DWI-ASPECTS were analyzed using Spearman's rank correlation coefficient. Mean differences and limit of agreement (LoA) between CT-ASPECTS and follow-up DWI-ASPECTS were assessed using the Bland–Altman plots. Multivariate logistic regression and receiver operating characteristic curve analyses were used to identify independent factors and evaluate their performances in predicting the clinical outcomes.ResultsVPCT-ASPECTS exhibited the highest correlation with follow-up DWI-ASPECTS (r = 0.846, P < 0.001), followed by APCT-ASPECTS (r = 0.613, P < 0.001) and NCCT-ASPECTS (r = 0.557, P < 0.001). The mean difference between VPCT-ASPECTS and follow-up DWI-ASPECTS was 0.0 (limit of agreement = −2.1 to 2.1). National Institute of Health Stroke Scale (NIHSS) scores at admission (NIHSSpre) (odds ratio [OR]=1.162, 95% confidence interval [CI]=1.063–1.270; P = 0.001) and VPCT-ASPECTS (OR=0.728, 95% CI=0.535–0.991; P = 0.044) were the independent factors associated with clinical outcomes. The combined model integrating NIHSSpre and VPCT-ASPECTS exhibited an excellent performance in predicting good clinical outcomes (area under curve [AUC]=0.807; sensitivity=75.0%; specificity=72.3%).ConclusionVPCT-ASPECTS may be a promising imaging biomarker to predict the final IC and the clinical outcome of the patients with AIS after EVT.

Acta Radiologica, Ahead of Print. <br/>BackgroundPelvic floor dysfunction (PVD), a prevalent clinical issue impacting quality of life, can be effectively assessed using magnetic resonance defecography (MRD) with the patient either supine or in the lateral decubitus position.PurposeTo compare the measurement value and grading in dynamic MRD within the closed-magnet system of PFD patients performed in supine versus lateral decubitus position using the H line, M line, and organ prolapse (HMO) classification system.Material and MethodsDuring 2017–2019, 100 patients with PFD underwent MRD during defecation in both supine and lateral decubitus positions. MR images were measured and graded by two blinded radiologists. The mean value of each HMO parameter and grading severity were compared between supine and lateral positions. Image quality (IQ) between two positions was also evaluated. Paired t-test and Wilcoxon ranked test were performed for significant difference. P < 0.05 was considered statistically significant.ResultsFor HMO measurement, M-line, levator plate angle (LPA), urethral hypermobility (UH), uterine prolapse, and peritoneocele had significantly higher mean values when measured in the lateral decubitus position than in the supine position. For grading, M-line, uterine prolapse, and peritoneocele also had more grading severity in the lateral decubitus than supine position with statistical significance (P = 0.002, 0.004, and 0.001, respectively). Only anterior rectocele had a mean value and grading severity in the supine more than the lateral position (P = 0.003 and P = 0.005). IQ in the supine was better than in the lateral decubitus position (P < 0.001).ConclusionMRD in lateral decubitus showed a more severe degree of PFD in most parameters based on the HMO grading system irrespective of inferior imaging quality.

Acta Radiologica, Ahead of Print. <br/>BackgroundSigmoid sinus wall reconstruction (SSWR) is an effective treatment for pulsatile tinnitus (PT). However, follow-up postoperative imaging manifestations have not been extensively reported.PurposeTo evaluate the morphological changes in patients with PT after successful SSWR using ultra-high-resolution computed tomography (U-HRCT).Material and MethodsData were retrospectively analyzed from 10 patients with PT who underwent successful SSWR primarily with autologous bone powder. U-HRCT scans were performed within 3 days of surgery and repeated 6 months later. The integrity, relative density, extent, and shape of the repaired wall were analyzed. The chi-square test was used to compare the categorical variables and the Phi (φ) coefficient was used to represent the magnitude of the correlation.ResultsAmong the 10 patients with PT, 1 (10%) achieved complete coverage of the defect with the residual bone, 8 (80%) had partial coverage, and 1 (10%) showed complete separation. A gap between the repaired wall and residual bone in the initial U-HRCT was linked to incomplete defect coverage in the subsequent U-HRCT scan (P < 0.001, φ = 0.903). The repaired wall shrank from the periphery to the center and the density increased. The repaired wall compressed into the sigmoid sinus retracts over time, reshaping into a naturally curved sigmoid sinus sulcus.ConclusionMorphological remodeling is a typical characteristic of the repaired sigmoid sinus wall in patients with PT. Short-term incomplete repair may imply incomplete coverage of the defect in the future, but this is not correlated with recurrence.

Acta Radiologica, Ahead of Print. <br/>BackgroundThe recognition of thin marginal spinal syndesmophytes is important, in part due to their association with non-traumatic or mildly traumatic vertebral fractures.PurposeTo determine a lower limit on the prevalence of marginal spinal syndesmophytes using chest radiographs.Material and MethodsWe conducted a retrospective analysis of 500 chest radiographs, assessing the prevalence of thin marginal syndesmophytes, bridging or near-bridging osteophytes, and flowing paravertebral ossifications in the thoracic intervertebral discs among individuals aged 16 years and older in a North American city.ResultsAmong the 500 participants, we observed that thin vertical marginal syndesmophytes were present in 17 (3.4%) cases, bridging or near-bridging osteophytes were present in 126 (25.2%) cases, and flowing paravertebral ossifications were present in 37 (7.4%) cases. Out of the 17 participants with thin marginal syndesmophytes, 10 exhibited a bamboo-like spine appearance, defined as the presence of ≥4 contiguous levels of bridging marginal syndesmophytes. Analysis of syndesmophyte distribution per vertebral level indicated a higher frequency of involvement in the mid to lower thoracic spine, maximal at T9/10.ConclusionsThe presence of thin marginal syndesmophytes in the thoracic spine on routine chest radiographs is substantially more prevalent than would be anticipated based on the existing literature. The feasibility of reliably identifying these syndesmophytes in the spine and the impact of this on morbidity should be further investigated due to their association with advanced ankylosing spondylitis and their susceptibility to fractures.

Acta Radiologica, Ahead of Print. <br/>BackgroundDouble-concentration magnetic resonance imaging (MRI) contrast agents are frequently used in contrast-enhanced MR angiography (CE-MRA) of the head and neck. To avoid mistiming the peak concentration of intraluminal contrast (due to shorter duration of peak), a second acquisition is sometimes performed.PurposeTo evaluate additional information from the second acquisition of CE-MRA and compare the collateral scoring to the hypoperfusion index obtained on MR perfusion, and to investigate presence of pseudo-occlusion using the second phase of CE-MRA.Material and MethodsA retrospective study was conducted. CE-MRA of the brain/neck, dynamic susceptibility contrast (DSC) MR perfusion scan (in majority) and subsequent digital subtraction angiography (DSA) were evaluated in patients with previous acute internal carotid artery (ICA)/middle cerebral artery (MCA) occlusion. Evaluation of CE-MRA/MR perfusion and DSA was performed by three experienced neuroradiologists and one neurointerventionist, respectively.ResultsThe site of ICA occlusion was seen to be distal to the site noted on early arterial phase (pseudo-occlusion of ICA) in 28.5% of patients. A significant negative correlation was seen between a higher HIR and collateral score.ConclusionEvaluation of second phase CE-MRA can provide valuable information that may be otherwise lost if only the early arterial phase is evaluated.