Acta radiologica最新文献

Background: May-Thurner syndrome (MTS) is a continuous pathological change of the left common iliac vein intraluminal wall due to compression between the right common iliac artery and a lumbar vertebra, with clinical signs of compromised venous drainage of the left leg, which eventually leads to development of left-sided deep vein thrombosis (DVT).

Purpose: To analyze the correlation between iliac vessel geometry and probability of DVT in patients with MTS.

Material and methods: This study consists of two age-matched female groups: DVT (n = 21) and control (n = 28). Iliac vein geometry, including left common iliac vein (LCIV) diameter, percentage of stenosis, angle between LCIV and right common iliac vein (RCIV), tilt angle of each CIV with horizontal line, and crossing angle between right common iliac artery (RCIA) and LCIV, were measured on computed tomography venography (CTV) images. The probability of DVT development was assessed using logistic regression.

Results: Comparing the DVT and control groups, the mean LCIV diameter was 2.4 mm and 3.7 mm (P = 0.001), and mean LCIV stenosis was 77.7% and 68.3% (P = 0.001), respectively. After age-adjustment, the odds of left DVT in patients with MTS correlated with LCIV diameter (odds ratio [OR]=0.25, P < 0.001, 95% confidence interval [CI]=0.11-0.54), LCIV stenosis (%) (OR=1.12, P = 0.003, 95% CI=1.04-1.21), LCIV tilt angle (OR=0.95, P < 0.038, 95% CI=0.91-0.99), and angle between two CIVs (OR=1.04, P < 0.039, 95% CI=1.00-1.09).

Conclusion: LCIV diameter and percentage of stenosis, LCIV tilt angle, and CIV angle were independent risk factors for the development of DVT in patients with MTS.

Background: Placenta previa is an obstetric complication related to severe maternal morbidity and mortality. Magnetic resonance imaging (MRI) can be used for the preoperative evaluation of postpartum hemorrhage.

Purpose: To investigate the value of MRI-based radiomics analysis in predicting postpartum hemorrhage among pregnant women with placenta previa.

Material and methods: Preoperative T2-weighted MRI and related clinical data of 371 patients were retrospectively collected, and these patients were randomly allocated into two subsets: the training dataset (n = 260) and the validation dataset (n = 111). The logistic regression (LR) classifier was used for the development of the radiomics model and the calculation of the radiomics score (Radscore).

Results: A total of eight radiomics features and five clinical features were selected for model development. The area under the receiver operating characteristic curve (AUC) of the radiomics model in the training and validation datasets were 0.929 (95% confidence interval [CI] = 0.891-0.957) and 0.914 (95% CI = 0.846-0.959), respectively. Combined with clinical factors, nomograms demonstrated improved diagnostic efficacy, with an AUC of 0.968 (95% CI = 0.939-0.986) in the training dataset and 0.947 (95% CI = 0.888-0.981) in the validation dataset.

Conclusion: The MRI-based model has certain value in predicting postpartum hemorrhage in pregnant women with placenta previa.

Background: Hydatid disease is a parasitic infection seen in endemic areas. Musculoskeletal hydatid disease is rarely reported.

Purpose: To describe the magnetic resonance imaging (MRI) features of musculoskeletal hydatid disease and to highlight the specific findings in the diagnosis of hydatid cysts.

Material and methods: The MRI scans of 29 cases diagnosed as musculoskeletal hydatid disease between 2000 and 2022 were retrospectively analyzed. The localization, size, appearance (unilocular or multilocular), signal characteristics, rim sign, presence of internal septa and membrane, and gadolinium enhancement pattern of hydatid cysts were evaluated.

Results: A total of 29 patients diagnosed with hydatid cyst were included in the study. Of the lesions, 18 were localized in bone and 11 were in soft tissue. The bone hydatid cysts on MRI showed heterogeneous low to intermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images in the medullary bone. In 15/18 patients, there was also cortical destruction and extension into the adjacent soft tissue planes. In 8/11 cases where the cyst was located in muscle tissue, the "cyst or cysts within a cyst" appearance was observed on MRI. The rim sign was observed in 7/11 cases and the "water lily" sign was noted in 2/11 cases.

Conclusion: MRI provides valuable information for the diagnosis of hydatid disease with its distinctive imaging features. Knowledge of the different patterns of hydatid cysts on MRI may be helpful in the diagnosis of this disease.

Background: The 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.

Purpose: To 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 methods: Two 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.

Results: The 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.

Conclusion: The 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.

Background: The capsular ligaments at the hip joint work in synchrony with the acetabulum and femoral head for articular stability. There is a lack of understanding about ischiofemoral ligament (ISFL) anatomy and function.

Purpose: To assess the insertion of the ISFL in non-arthritic adult hips.

Material and methods: A retrospective analysis was performed in 72 patients who underwent magnetic resonance arthrogram (MRA) for the assessment of hip pain. The distribution of the ISFL components, the thickness, and the insertion site were assessed by concomitantly using the axial oblique, coronal, and sagittal MRA images.

Results: Two insertions of the ISFL anterior to the center of the femoral head were identified in 71 (99%) hips: (i) predominant anterior merging with the iliofemoral ligament as continuation of zona orbicularis, observed in all hips; and (ii) anterolateral junction of femoral neck and greater trochanter. Two ISFL parts (proximal and distal) were identified in 70 (97%) of the 72 studied hips. The proximal part was always thinner (mean 2.6 ± 0.7 mm) and originated from the ischium at the acetabular rim. The distal part was a continuation of the zona orbicularis, and the mean thickness was 6.7 ± 1.6 mm. Both parts merged as they coursed over the superior portion of the femoral head.

Conclusion: The predominant insertion of the ischiofemoral ligament is a merging to the iliofemoral ligament anteriorly. Surgical procedures such as hip arthroscopy involving the ISFL will affect the function of the iliofemoral ligament, and vice versa.

Background: Photon-counting detector computed tomography (PCD-CT) is a groundbreaking technology with promising results for visualization of small bone structures.

Purpose: To analyze the delineation of the thoracic spine in multiplanar reconstructions (MPR) on PCD-CT compared to energy-integrating detector (EID)-CT.

Material and methods: Two euthanized mice were examined using different scanners: (i) 20-slice EID-CT and (ii) dual-source PCD-CT at various CTDI_Vol values. Readers evaluated the thoracic spine and selected series with best visualization among signal-to-noise ratio (SNR)-matched pairs.

Results: SNR 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.

Conclusion: MPR 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.

Background: Bleeding 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.

Purpose: To evaluate the safety and efficacy of tract embolization with gelatin sponge strips after percutaneous transhepatic poral vein access.

Material and methods: Between 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.

Results: No 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.

Conclusion: Tract embolization with gelatin sponge strips after percutaneous transhepatic portal vein intervention is a safe and feasible method for preventing hemorrhage from the puncture tract.