CT and MRI Findings of Solitary Extramedullary Plasmacytoma: A Series of Ten Case Reports and Review of Literature.

OBJECTIVE: The study aimed to analyze computed tomography and magnetic resonance imaging features of patients with solitary extramedullary plasmacytoma. METHODS: Ten cases with solitary extramedullary plasmacytoma were included in this study. CT and MRI features of solitary extramedullary plasmacytoma were retrospectively analyzed. RESULTS: This study included both males (n = 8) and females (n = 2), with a median age of 48 (range 21-72 years old). The organs or anatomical structures involved were nasopharynx (n = 3), orbit (n = 1), left tentorium (n = 1), nasal cavity and meatus (n = 2), small intestine and mesentery (n = 1), as well as posterior thoracic wall (n = 2). The median maximum diameter of the tumors was 3.2 cm (range 0.8- 15.2 cm). The tumor shapes were round (n = 7), stripped (n = 1), irregular (n = 1), and nodular (n = 1). The margin of the tumors was well-defined (n = 7) and partially well-defined (n = 3). There were 3 cases with bone destruction and 1 with a tissue invasion adjacent to the tumor, calcification (n = 1), and cystic degeneration (n = 2). Enlarged tumoral vessels (n = 4) could also be observed. The CT attenuation and MR signal intensity of tumors were heterogeneous (n = 4) and homogenous (n = 6). After the injection of the contrast agent, marked (n = 5), mild (n = 1), mild to moderate (n = 1), and delayed enhancement (n = 1) could be observed. CONCLUSION: A well-defined homogeneous solitary mass occurring at the head and neck with a marked enhancement, an adjacent tissue invasion, enlarged tumoral vessels, and bone destruction can indicate the diagnosis of solitary extramedullary plasmacytoma.

Disrupted resting-state interhemispheric functional connectivity in systemic lupus erythematosus patients with and without neuropsychiatric lupus.

PURPOSE: The aim of the study is to explore interhemispheric homotopic functional connectivity alterations in systemic lupus erythematosus (SLE) patients with and without neuropsychiatric lupus (NPSLE and non-NPSLE, respectively) and their potential correlations with clinical characteristics and neuropsychological performance. METHODS: Based on resting-state functional MRI (rs-fMRI) data collected from SLE patients and matched healthy controls (HCs), the voxel-mirrored homotopic connectivity (VMHC) analysis was conducted to measure functional homotopy. Subsequently, correlations between altered functional homotopy and clinical/neuropsychological data were analyzed. RESULTS: Compared with the HC group, both NPSLE and non-NPSLE groups showed attenuated homotopic connectivity in middle temporal gyrus (MTG), cuneus (CUN), middle occipital gyrus (MOG), angular gyrus (ANG), and postcentral gyrus (PoCG). NPSLE patients also exhibited decreased homotopic connectivity in inferior parietal gyrus (IPG) and middle frontal gyrus (MFG). Compared with non-NPSLE patients, NPSLE patients showed weaker interhemispheric homotopic functional connectivity in MOG. Decreased homotopic functional connectivity in PoCG, IPG, and MOG were associated with the anxiety state of SLE patients. CONCLUSIONS: Our findings revealed attenuated functional homotopy in both NPSLE and non-NPSLE groups compared to the HC group, which appeared to be more severe in patients with comorbid neuropsychiatric lupus. Interhemispheric homotopy dysconnectivity may participate in the neuropathology of anxiety symptoms in SLE.

White Matter Microstructural Abnormalities of the Visual Pathway in Type 2 Diabetes Mellitus: A Generalized Q-sampling Imaging Study.

RATIONALE AND OBJECTIVES: Neurodegeneration is an early event in the pathogenesis of diabetic retinopathy (DR). We assessed the white matter microstructural integrity of the visual pathway in diabetes patients vs. healthy subjects, and investigated the advantages of generalized Q-sampling imaging (GQI) in the assessment of the visual pathway. MATERIALS AND METHODS: T1-weighted, T2-weighted fluid-attenuated inversion recovery, and simultaneous multislice- diffusion sequences were acquired from 21 DR patients, 29 diabetes patients without DR (NDR group), and 28 age- and gender-matched healthy controls. Diffusion source images were reconstructed to GQI. Region of interest (ROI)-based analysis was utilized to evaluate microstructural alterations in the visual pathway. Multivariate linear regression analysis (forward stepwise method) was performed to investigate associations between clinical data and mean GQI parameters. RESULTS: ROI-based analyses indicated that the GQI parameters generalized fractional anisotropy, quantitative anisotropy (QA), and normalized QA (NQA) were significantly lower in the NDR group than in the healthy controls, and even lower in the DR group than in the NDR group. Disease duration was significantly and negatively correlated with mean generalized fractional anisotropy and mean NQA. CONCLUSION: GQI could sensitively and non-invasively evaluate the visual pathway in diabetes patients. The nerve fibers of the visual pathway were damaged before the onset of retinopathy, and this damage was aggravated after retinopathy onset, as a consequence of long exposure to hyperglycemia.