ACTA Radiologica (Test)

Acta Radiologica, Ahead of Print. <br/>BackgroundDeep learning reconstruction (DLR) with denoising has been reported as potentially improving the image quality of magnetic resonance imaging (MRI). Multi-modal MRI is a critical non-invasive method for tumor detection, surgery planning, and prognosis assessment; however, the DLR on multi-modal glioma imaging has not been assessed.PurposeTo assess multi-modal MRI for glioma based on the DLR method.Material and MethodsWe assessed multi-modal images of 107 glioma patients (49 preoperative and 58 postoperative). All the images were reconstructed with both DLR and conventional reconstruction methods, encompassing T1-weighted (T1W), contrast-enhanced T1W (CE-T1), T2-weighted (T2W), and T2 fluid-attenuated inversion recovery (T2-FLAIR). The image quality was evaluated using signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and edge sharpness. Visual assessment and diagnostic assessment were performed blindly by neuroradiologists.ResultsIn contrast with conventionally reconstructed images, (residual) tumor SNR for all modalities and tumor to white/gray matter CNR from DLR images were higher in T1W, T2W, and T2-FLAIR sequences. The visual assessment of DLR images demonstrated the superior visualization of tumor in T2W, edema in T2-FLAIR, enhanced tumor and necrosis part in CE-T1, and fewer artifacts in all modalities. Improved diagnostic efficiency and confidence were observed for preoperative cases with DLR images.ConclusionDLR of multi-modal MRI reconstruction prototype for glioma has demonstrated significant improvements in image quality. Moreover, it increased diagnostic efficiency and confidence of glioma.

Acta Radiologica, Ahead of Print. <br/>BackgroundThe status of axillary lymph nodes (ALN) plays a critical role in the management of patients with breast cancer. It is an urgent demand to develop highly accurate, non-invasive methods for predicting ALN statusPurposeTo evaluate the efficacy of ultrasound radiofrequency (URF) time-series parameters, in combination with clinical data, in predicting ALN metastasis in patients with breast cancer.Material and MethodsWe prospectively gathered clinicopathologic and ultrasonic data from patients diagnosed with breast cancer. Various machine-learning (ML) models were developed using all available features to determine the most efficient diagnostic model. Subsequently, distinct prediction models were created using the optimal ML model, and their diagnostic performances were evaluated and compared.ResultsThe study encompassed 240 patients, of whom 88 had lymph node metastases. A leave-one-out cross-validation (LOOCV) method was used to split the entire dataset into training and testing subsets. The random forest ML model outperformed the other algorithms, with an area under the curve (AUC) of 0.92. Prediction models based on clinical, ultrasonic, URF parameters, clinical + ultrasonic, clinical + URF, and ultrasonic + URF parameters had AUCs of 0.56, 0.79, 0.78, 0.90, 0.80, and 0.84, respectively, in the testing set. The comprehensive diagnostic model (clinical + ultrasonic + URF parameters) demonstrated strong diagnostic capability, with an AUC of 0.94 in the testing set, exceeding any single prediction model.ConclusionThe combined model (clinical + ultrasonic + URF parameters) could be used preoperatively to predict lymph node status, offering valuable input for the design of individualized surgical approaches.

Acta Radiologica, Ahead of Print. <br/>BackgroundAn increased prevalence of benign lesions has been associated with the increased use of radiological tools in orthopedic practice.PurposeTo investigate the inter-observer reliability of the radiographic detection of lesions on the proximal humerus between different observers.Material and MethodsX-ray radiological examinations of 17,243 patients were performed by an orthopedic surgeon to assess the presence of proximal humeral bone lesions. After this initial screening, 201 patients with lesions were identified and these 201 scans were assessed by three different physicians: an orthopedic oncologist, an orthopedic surgeon, and a musculoskeletal radiologist. Of the 201 patients with lesions, 80 had magnetic resonance imaging in addition to X-rays and were assessed. The diagnosis of the lesions was determined by each participant according to their radiological appearance to assess inter-observer reliability.ResultsThe prevalence of proximal humeral lesions was determined by the orthopedic surgeon to be 1.165% (201 of 17,243 patients). In 201 patients with a lesion, the mean age was 48 ± 17 years (range = 18–91 years). According to the assessments of the orthopedic oncologist, orthopedic surgeon, and musculoskeletal radiologist, the most common bone lesion identified was enostosis, with prevalence percentages of 53.7%, 59.7%, and 64.7%, respectively. A noteworthy consensus exists in the collective diagnosis of bone lesions among the three investigators, demonstrated by a substantial agreement with Fleiss’ κ at 0.74 (P < 0.001).ConclusionThere was remarkable agreement between the three investigators on the collective diagnosis of bone lesions. Enostosis was the most common bone lesion at the proximal humerus in our series.

Acta Radiologica, Ahead of Print. <br/>BackgroundThe management of patients with slipped capital femoral epiphysis (SCFE) requires imaging diagnostics of good quality and accurate measurement of the degree of slippage. In Sweden, three different radiological methods are commonly used: the calcar femorale method; the Billing method; and the Head-shaft angle described by Southwick.PurposeTo evaluate whether any of the three most common methods used in Sweden to measure the slip angle was more useful and reproducible than the others.Material and MethodsTwo experienced orthopaedists measured the slip angle in preoperative hip radiographs. Intra- and inter-observer variability between the two experienced observers and the reported value by clinicians who treated the child with SCFE was evaluated.ResultsThe intraclass correlation coefficient (ICC) confidence interval (CI) between the two experienced observers and the reporting clinicians overlapped for the three methods. In 37% of the cases, the difference was more than 5° between the experienced observers’ measurement and the reported value by clinicians. The two experienced orthopaedists' intra- and inter-observer variability was low.ConclusionThe observer's experience is more important than the method of choice when measuring the slip angle in SCFE. The research group recommends the calcar femorale method due to its feasibility on the versatile and commonly used frog leg lateral view.

Acta Radiologica, Ahead of Print. <br/>BackgroundPreoperative prediction of lymphovascular space invasion (LVSI) is crucial for improving the prognosis of patients with cervical cancer.PurposeTo evaluate the value of preoperative amide proton transfer (APT) imaging combined with serum CA125 levels for predicting LVSI in cervical cancer.Material and MethodsThis retrospective study included 80 patients with cervical cancer who underwent preoperative magnetic resonance imaging, including APT imaging. Serum CA125 levels were measured using a fully automated immunoassay analyzer and chemiluminescence method. The presence of LVSI was determined based on the pathological results after surgery.ResultsAmong the 40 patients who met the requirements, 29 had postoperative pathological confirmation of LVSI, while 11 did not. The areas under the receiver operating characteristic curves (AUC) of preoperative APT and CA125 levels predicting LVSI were 0.889 and 0.687, respectively. When the APT value was 2.9%, the corresponding Youden index was the highest (0.702), with a sensitivity of 79.3% and specificity of 90.9%. When the critical value of the preoperative serum CA15 level was 25.3 u/mL, the corresponding Youden index was the highest (0.508), with a sensitivity of 69.0% and a specificity of 81.8%. The sensitivity and specificity of preoperative APT imaging combined with serum CA125 in predicting LVSI were 82.7% and 100%, respectively, with a Youden's index of 0.828 and an AUC of 0.923.ConclusionThe combination of preoperative APT imaging and serum CA125 levels is valuable for predicting LVSI in cervical cancer. Diagnostic efficacy is highest when the APT value is >2.9% and the serum CA125 level is >25.3 u/mL.

Acta Radiologica, Ahead of Print. <br/>BackgroundBleeding from the puncture tract after percutaneous transhepatic portal vein intervention can become life-threatening. To date, studies about tract embolization with gelatin sponge after percutaneous transhepatic portal vein intervention are only with small numbers of patients, or non-consecutive or pediatric patients with a relatively small sheath in diameter.PurposeTo evaluate the safety and efficacy of tract embolization with gelatin sponge strips after percutaneous transhepatic poral vein access.Material and MethodsBetween September 2017 and February 2024, 100 consecutive patients (61 men, 39 women; mean age = 53 ± 15 years) underwent a total of 105 portal vein interventions using a percutaneous transhepatic approach. Tract embolization for the removal of 6–8 Fr sheath was performed using gelatin sponge strips in all procedures, including 71 portal vein embolization before major hepatectomy, 27 portal balloon venoplasty or stent placement after liver transplantation, and seven other interventions.ResultsNo bleeding occurred after tract embolization with gelatin sponge strips. Minor portal vein thrombosis was detected in three procedures after liver transplantation and in one procedure for portal vein stenosis caused by essential thrombocytopenia. Thrombosis occurred in the punctured portal vein branch in all procedures. Thrombosis was not clinically relevant in any patient, and it was difficult to differentiate whether thrombosis was caused by sheath placement or the inserted gelatin sponge.ConclusionTract embolization with gelatin sponge strips after percutaneous transhepatic portal vein intervention is a safe and feasible method for preventing hemorrhage from the puncture tract.

Acta Radiologica, Ahead of Print. <br/>BackgroundPhoton-counting detector computed tomography (PCD-CT) is a groundbreaking technology with promising results for visualization of small bone structures.PurposeTo analyze the delineation of the thoracic spine in multiplanar reconstructions (MPR) on PCD-CT compared to energy-integrating detector (EID)-CT.Material and MethodsTwo euthanized mice were examined using different scanners: (i) 20-slice EID-CT and (ii) dual-source PCD-CT at various CTDIVol values. Readers evaluated the thoracic spine and selected series with best visualization among signal-to-noise ratio (SNR)-matched pairs.ResultsSNR was significantly higher in PCD-CT reconstructions (Br68) and lower in Hr98 reconstructions compared to EID-CT. Bone detail visualization was superior in PCD-CT (especially in Hr98 reconstructions) compared to EID-CT.ConclusionMPR on a PCD-CT had a higher SNR and better bone detail visualization even at lower radiation doses compared to EID-CT. PCD-CT with bone reconstructions showed the best delineation of small bone structures and might be considered in clinical routine.

Acta Radiologica, Ahead of Print. <br/>BackgroundHigh-resolution computed tomography (HRCT) is dependent on detailed morphology in diagnostic assessment of interstitial lung diseases. Photon-counting CT (PCCT) enables improved resolution while reducing radiation.PurposeTo compare if the image quality, detailed morphology, and radiation dose in HRCT of the lung improves with PCCT compared to energy-integrated CT (EICT).Material and MethodsHRCT with PCCT in patients with body mass index (BMI) from normal to obese, previously examined with different EICT were included. They were evaluated in a five-step scale for image quality according to Quality Criteria for CT (Diagnostic Requirement of the ImPACT group-European standardization). In addition, ground-glass opacities, bronchiectasis, emphysema, nodules, and subpleural detailed morphology (≤1 cm from the pleural border) were evaluated by three independent thoracic and/or pediatric radiologists. Visual grading characteristics (VGC) were used for comparison of image quality and detailed morphology and Fleiss kappa for intra-observer variability. Dose-length product (DLP) and CT dose index-volume (CTDIvol) were collected to calculate effective radiation dose.ResultsHRCT with PCCT in 52 women and 48 men (mean age=67.2 ± 13.6 years; age range=27–87 years; BMI=26.9 kg/m2; range=18.6–45 kg/m2) previously examined with EICT (mean age=65.3 ± 13.6 years; age range=27–85 years; BMI=27 kg/m2; range=18.9–45 kg/m2) were included. There were significant differences in image quality for all entities in favor of PCCT. The radiation dose was reduced with PCCT by 47% in all, particularly pronounced in obese with 48.5%.ConclusionImage quality, detailed morphology, and radiation dose, particularly in obese patients, were significantly improved in HRCT with PCCT compared to conventional EICT. The new technique enables visualization of subpleural structures.

Acta Radiologica, Ahead of Print. <br/>

Acta Radiologica, Ahead of Print. <br/>BackgroundPhoton-counting computed tomography (PCCT) enables new ways of image reconstruction, e.g. material decomposition and creation of virtual non-contrast (VNC) series with higher resolution and lower radiation dose than standard computed tomography (CT). Clinical experiences of this are limited.PurposeTo compare true non-contrast (TNC) series with VNC series derived from non-enhanced (VNCu), arterial phase (VNCa) and portal venous phase (VNCv) in clinically approved PCCT.Material and MethodsA total of 45 clinical, tri-phasic abdominal CT scans from the PCCT Naetom Alpha, between February 2022 and November 2022, were retrospectively assessed. Placing a region of interest in six different locations in each VNC series – right liver parenchyma, left liver parenchyma, spleen, aorta, erector spinae muscle, and in the subcutaneous fat – absolute Hounsfield values (HU) and standard deviations (SD) were collected. Differences in HU (ΔHU) were compared and statistically analyzed.ResultsStatistically significant differences between VNC and TNC were seen in all measurements, with the largest difference in the subcutaneous fat and the smallest difference in the erector spinae muscle. Only small differences were seen between VNCa and VNCv, where the largest differences were seen in the left and right liver lobes.ConclusionVNC images from the first-generation clinically approved PCCT showed a significant difference between VNC and TNC images. The differences vary with the type of tissue. Only small differences were seen depending from which contrast phase the VNC was derived.