Risk Factors for New Adjacent and Remote Vertebral Fracture After Percutaneous Vertebroplasty.

OBJECTIVE: To analyze the risk factors of new adjacent vertebral fractures (AVF) and remote vertebral fractures (RVF) after percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs). METHODS: Patients who underwent additional PVP for new OVCFs were enrolled. In addition, we set a 1:1 age-, sex-, surgical segment-, and surgical date-matched control group, in which patients underwent PVP without new OVCFs. Data on body mass index, occurrence time of second PVP, vertebral computed tomography (CT) Hounsfield Unit (HU) at the fracture adjacent segment, and RVF segment were collected. RESULTS: A total of 44 patients who underwent additional PVP for new OVCFs at our hospital were included. AVF occurred significantly earlier than RVF (13.5 ± 14.1 vs. 30.4 ± 20.1 months, P = 0.007). Compared to the control group, the AVF segment CT HU was significantly lower in patients with AVF (28.7 ± 16.7 vs. 61.3 ± 14.7, P = 0.000), while there was no significant difference between patients with RVF and control group including both adjacent and RVF segment CT HU. Receiver operating characteristic curves identified a cutoff value of 43 for using adjacent segment CT HU to differentiate patients with AVF from controls, with a sensitivity of 80% and a specificity of 88.9%. CONCLUSIONS: Our study showed that the risk factors for AVF and RVF after PVP surgery were different. The occurrence of AVF was earlier and associated with low adjacent segment CT HU values, whereas the preoperative CT HU in both adjacent and RVF segments was not found to be associated with RVF.

A new classification and regression tree algorithm: Improved diagnostic sensitivity for HCC ≤ 3.0 cm using gadoxetate disodium-enhanced MRI.

PURPOSE: To develop and validate an effective algorithm, based on classification and regression tree (CART) analysis and LI-RADS features, for diagnosing HCC ≤ 3.0 cm with gadoxetate disodium­enhanced MRI (Gd-EOB-MRI). METHOD: We retrospectively included 299 and 90 high-risk patients with hepatic lesions ≤ 3.0 cm that underwent Gd-EOB-MRI from January 2018 to February 2021 in institution 1 (development cohort) and institution 2 (validation cohort), respectively. Through binary and multivariate regression analyses of LI-RADS features in the development cohort, we developed an algorithm using CART analysis, which comprised the targeted appearance and independently significant imaging features. On per-lesion basis, we compared the diagnostic performances of our algorithm, two previously reported CART algorithms, and LI-RADS LR-5 in development and validation cohorts. RESULTS: Our CART algorithm, presenting as a decision tree, included targetoid appearance, HBP hypointensity, nonrim arterial phase hyperenhancement (APHE), and transitional phase hypointensity plus mild-moderate T2 hyperintensity. For definite HCC diagnosis, the overall sensitivity of our algorithm (development cohort 93.2%, validation cohort 92.5%; P < 0.006) was significantly higher than those of Jiang's algorithm modified LR-5 (defined as targetoid appearance, nonperipheral washout, restricted diffusion, and nonrim APHE) and LI-RADS LR-5, with the comparable specificity (development cohort: 84.3%, validation cohort: 86.7%; P ≥ 0.006). Our algorithm, providing the highest balanced accuracy (development cohort: 91.2%, validation cohort: 91.6%), outperformed other criteria for identifying HCCs from non-HCC lesions. CONCLUSIONS: In high-risk patients, our CART algorithm developed with LI-RADS features showed promise for the early diagnosis of HCC ≤ 3.0 cm with Gd-EOB-MRI.

The role of enhancing capsule and modified capsule appearances in LI-RADS for diagnosing HCC ≤ 3.0 cm on gadoxetate disodium-enhanced MRI.

OBJECTIVES: To evaluate the value of using enhancing capsule (EC) or modified capsule appearance as a major feature in LI-RADS for diagnosing HCC ≤ 3.0 cm on gadoxetate disodium-enhanced MRI (Gd-EOB-MRI), and to explore the relationship between the imaging features and the histological fibrous capsule. METHODS: This retrospective study enrolled 342 hepatic lesions ≤ 3.0 cm in 319 patients that underwent Gd-EOB-MRIs from January 2018 to March 2021. During dynamic phases and hepatobiliary phase, the modified capsule appearance added the nonenhancing capsule (NEC) (modified LI-RADS + NEC) or corona enhancement (CoE) (modified LI-RADS + CoE) to EC as an alternative capsule appearance. Inter-reader agreement of imaging features was assessed. The diagnostic performances of LI-RADS, LI-RADS with EC ignored, and two modified LI-RADS were compared, followed by Bonferroni correction. Multivariable regression analysis was performed to identify the independent features associated with the histological fibrous capsule. RESULTS: The inter-reader agreement on EC (0.64) was lower than that on the NEC alternative (0.71) but better than that on CoE alternative (0.58). For HCC diagnosis, compared to LI-RADS, LI-RADS with EC ignored showed significantly lower sensitivity (72.7% vs. 67.4%, p < 0.001) with comparable specificity (89.3% vs. 90.7%, p = 1.000). Two modified LI-RADS showed slightly higher sensitivity and lower specificity than LI-RADS, without statistical significance (all p ≥ 0.006). The AUC was highest with modified LI-RADS + NEC (0.82). Both EC and NEC were significantly associated with the fibrous capsule (p < 0.05). CONCLUSION: EC appearance improved the diagnostic sensitivity of LI-RADS for HCC ≤ 3.0 cm on Gd-EOB-MRI. Considering NEC as an alternative capsule appearance allowed for better inter-reader reliability and comparable diagnostic ability. KEY POINTS: • Using the enhancing capsule as a major feature in LI-RADS significantly improved the sensitivity of diagnosing HCC ≤ 3.0 cm without reducing specificity on gadoxetate disodium-enhanced MRI. • Compared to the corona enhancement, the nonenhancing capsule might be a preferable alternative capsule appearance for diagnosing HCC ≤ 3.0 cm. • Capsule appearance should be considered a major feature in LI-RADS for diagnosing HCC ≤ 3.0 cm, regardless whether the capsule appears to be enhancing or nonenhancing.

Imaging findings of retroperitoneal anastomosing hemangioma: a case report and literature review.

BACKGROUND: Anastomosing hemangioma is an uncommon benign vascular tumor that may be mistaken for a malignancy. The imaging findings of anastomosing hemangioma are not well provided from the previous reports. Herein, in the study, we discuss the imaging findings for one case of retroperitoneal anastomosing hemangioma. CASE PRESENTATION: One 64-year-old female patient had a left retroperitoneal mass that was incidentally detected upon physical examination. A hypoechoic mass with abundant blood flow signals was found by US in the perirenal space. CT and MRI detected a large cystic and solid lesion in the left retroperitoneal space. Plain CT indicated that the internal density was uneven, and the pattern of enhancement was obvious and progressive. MRI-T2WI showed high intensity, DWI showed isointensity, and the mass also showed obvious progressive enhancement. Finally, anastomosing hemangioma was diagnosed via histopathological studies. CONCLUSION: As a rare and benign tumour, anastomosing hemangioma is easily misinterpreted. We suggest that the observation of "genitourinary tract related, well defined, hyperintensity or isointensity on T2WI, isointensity on DWI, and obvious progressive enhancement patterns likely to the vascular enhancement" may consider the diagnosis of AH.