T2 mapping and fat quantification of lumbar paraspinal muscle in ankylosing spondylitis: a case control study.

BACKGROUND: To compare changes in the composition of paraspinal muscles of patients with ankylosing spondylitis (AS) and matched healthy controls using T2 mapping and T2 IDEAL and correlate the quantitative magnetic resonance imaging (qMRI) results with clinical assessments of AS patients. METHOD: In total, 37 AS patients and 37 healthy controls were enrolled in the case control study. T2 mapping with and without fat saturation and IDEAL imaging were used to assess the multifidus (MF) and erector spinae (ES) at the levels of L3/L4 and L4/L5 for all subjects. Mean T2non-fatsat, T2fat, T2fatsat, cross-sectional area (CSA), and fat fraction (FF) were compared between AS and healthy controls. Correlations of qMRI results with clinical assessments were analyzed in AS. RESULTS: Significantly elevated mean T2non-fatsat values and the FF of the MF and ES at both levels were observed in AS and compared to the controls (p < 0.05). The mean T2fatsat values of ES and MF were significantly higher only at the level of L3/L4 in AS compared to healthy controls (p < 0.05). A loss of muscle CSA compatible with atrophy was present in MF and ES at both levels in AS compared to the controls (p < 0.05). Weak to moderate positive correlations were found between FF and age and disease duration in AS (r = 0.318-0.415, p < 0.05). However, such positive correlation was not observed between FF and disease duration after adjusting for age (p > 0.05). CONCLUSIONS: Our findings indicate that using a combination of IDEAL and T2 mapping may provide deeper insights into the pathophysiological degeneration of paraspinal muscles in AS.

Neuroradiologic Findings and Clinical Features of Meningiomas With Spontaneous Hemorrhagic Onset: A Single-center 10-year Experience.

OBJECTIVE: This study aimed to elucidate the clinicoradiologic features of spontaneous hemorrhagic meningiomas (HMs) and examine risk factors associated with meningioma hemorrhage. METHODS: We retrospectively reviewed 651 consecutive meningioma patients who underwent surgical resection in our hospital between January 2011 and January 2021. After exclusions, 169 patients were included for analysis. Patients were grouped according to presence of hemorrhage in the meningioma: the HM group (n = 19) and non-HM group (n = 150). Clinicoradiologic patient data were examined and compared using univariate and multivariate analysis. RESULTS: HMs accounted for 2.9% of the entire series of meningiomas. HMs were mainly located at the convexity (63.2%). Mean diameter of HMs was 4.8 cm. On computed tomography, most HMs appeared as mixed isodensity and hyperdensity (84.2%). On magnetic resonance imaging, most appeared as mixed isointensity and hyperintensity on T1-weighted imaging and mixed hypointesity and hyperintensity on T2-weighted imaging (52.6%). Seventeen tumors exhibited heterogeneous enhancement, a dural tail, and peritumoral brain edema. Thirteen showed intratumoral cystic change. The misdiagnosis rate was significantly higher in HMs than non-HMs (31.6% vs. 7.3%; P = 0.005). Intratumoral cystic change was the only independent predictor of meningioma hemorrhage in multivariate analysis (odds ratio 4.116; 95% confidence interval 1.138-14.894; P = 0.031). CONCLUSIONS: Mixed isodensity/intensity and hyperdensity/intensity on computed tomography/magnetic resonance imaging in conjunction with heterogenous enhancement, a dural tail, and varying degrees of peritumoral brain edema suggest a high possibility of HM. Presence of intratumoral cystic change was an independent risk factor associated with meningioma hemorrhage.

Misdiagnosis and Delay of Diagnosis in Hemorrhagic Meningioma: A Case Series and Review of the Literature.

OBJECTIVE: To evaluate the clinicoradiologic characteristics of hemorrhagic meningiomas (HMs) that are missed or misdiagnosed on radiologic imaging studies. METHODS: Clinical and radiologic data from 6 patients with HM who were initially misdiagnosed were collected and recorded respectively. In addition, we performed a literature review for misdiagnosed HM and summarized the results. RESULTS: Five of the 6 patients with misdiagnosed HM were female, and 1 was male. Both computed tomography (CT) and magnetic resonance imaging were performed in 4 patients, and CT alone was performed in 2. On CT, the HM was heterogeneously hyperdense in 5 patients and isodense in 1 patient. In all 4 patients who underwent magnetic resonance imaging, the HM was mixed iso- and hypointense on T1-weighted imaging and heterogeneously hyperintense on T2-weighted imaging. Marked heterogeneous contrast enhancement was observed in 2 patients, strong rim enhancement in 1, and peripheral enhancement in 1. The dural tail sign was seen in only 1 patient. The initial radiologic misdiagnoses were subdural hematoma (n = 1), malignant glioma (n = 1), ruptured arterial aneurysm (n = 1), metastasis (n = 2), and uncertain (n = 1). In the literature review, 22 cases of HM diagnostic error were collected. The main misdiagnoses were subdural hematoma (27.3%), traumatic hematoma (13.6%), vascular anomaly (13.6%), malignant glioma (4.5%), and metastasis (4.5%). CONCLUSIONS: Our study showed that in patients with HM with inadequate imaging evaluation, a small tumor associated with massive hematoma and atypical imaging features was more likely to be misdiagnosed.