Diffuse Large B-Cell Epstein-Barr Virus-Positive Primary CNS Lymphoma in Non-AIDS Patients: High Diagnostic Accuracy of DSC Perfusion Metrics.

BACKGROUND AND PURPOSE: Immunodeficiency-associated CNS lymphoma may occur in different clinical scenarios beyond AIDS. This subtype of CNS lymphoma is diffuse large B-cell and Epstein-Barr virus-positive. Its accurate presurgical diagnosis is often unfeasible because it appears as ring-enhancing lesions mimicking glioblastoma or metastasis. In this article, we describe clinicoradiologic features and test the performance of DSC-PWI metrics for presurgical identification. MATERIALS AND METHODS: Patients without AIDS with histologically confirmed diffuse large B-cell Epstein-Barr virus-positive primary CNS lymphoma (December 2010 to January 2022) and diagnostic MR imaging without onco-specific treatment were retrospectively studied. Clinical, demographic, and conventional imaging data were reviewed. Previously published DSC-PWI time-intensity curve analysis methodology, to presurgically identify primary CNS lymphoma, was used in this particular lymphoma subtype and compared with a prior cohort of 33 patients with Epstein-Barr virus-negative CNS lymphoma, 35 with glioblastoma, and 36 with metastasis data. Normalized curves were analyzed and compared on a point-by-point basis, and previously published classifiers were tested. The standard percentage of signal recovery and CBV values were also evaluated. RESULTS: Seven patients with Epstein-Barr virus-positive primary CNS lymphoma were included in the study. DSC-PWI normalized time-intensity curve analysis performed the best for presurgical identification of Epstein-Barr virus-positive CNS lymphoma (area under the receiver operating characteristic curve of 0.984 for glioblastoma and 0.898 for metastasis), followed by the percentage of signal recovery (0.833 and 0.873) and CBV (0.855 and 0.687). CONCLUSIONS: When a necrotic tumor is found in a potentially immunocompromised host, neuroradiologists should consider Epstein-Barr virus-positive CNS lymphoma. DSC-PWI could be very useful for presurgical characterization, with especially strong performance of normalized time-intensity curves.

Structural cortical network reorganization associated with early conversion to multiple sclerosis.

Brain structural covariance networks (SCNs) based on pairwise statistical associations of cortical thickness data across brain areas reflect underlying physical and functional connections between them. SCNs capture the complexity of human brain cortex structure and are disrupted in neurodegenerative conditions. However, the longitudinal assessment of SCN dynamics has not yet been explored, despite its potential to unveil mechanisms underlying neurodegeneration. Here, we evaluated the changes of SCNs over 12 months in patients with a first inflammatory-demyelinating attack of the Central Nervous System and assessed their clinical relevance by comparing SCN dynamics of patients with and without conversion to multiple sclerosis (MS) over one year. All subjects underwent clinical and brain MRI assessments over one year. Brain cortical thicknesses for each subject and time point were used to obtain group-level between-area correlation matrices from which nodal connectivity metrics were obtained. Robust bootstrap-based statistical approaches (allowing sampling with replacement) assessed the significance of longitudinal changes. Patients who converted to MS exhibited significantly greater network connectivity at baseline than non-converters (p = 0.02) and a subsequent connectivity loss over time (p = 0.001-0.02), not observed in non-converters' network. These findings suggest SCN analysis is sensitive to brain tissue changes in early MS, reflecting clinically relevant aspects of the condition. However, this is preliminary work, indicated by the low sample sizes, and its results and conclusions should be treated with caution and confirmed with larger cohorts.

Lipofilling as refinement procedure in maxillo-mandibular malformations.

Maxillo-mandibular asymmetry has numerous aetiologies: congenital, traumatic, iatrogenic and post-oncologic. Patients with congenital dentofacial malformations are generally submitted to orthognathic surgery and/or additional procedures (genioplasty, alloplastic implants) with satisfactory results. However, despite achieving skeletal symmetry, noticeable facial asymmetry may persist.This study was performed in 45 patients (29 women and 16 men) operated between December 2012 and June 2014. All patients were affected by maxilla-mandibular asymmetry and underwent orthognatic surgery for hard tissue correction of the deformity. Residual facial alterations were then treated with lipofilling refinement proceure. In all cases good integration of the grafted fat was observed in the recipient sites. Retrospective analysis of photographic documentation showed progressive volumetric decrease for up to approximately 6 months after surgery; after that graft volume remained relatively stable. There were no significant surgical complications, either from the fat harvest site or the reconstructed site. Mild oedema and bruising were frequent during the first post-operative week. No haematomas, infections, vascular or nervous injuries were recorded. Twenty-four patients felt the need to have a second procedure. A second fat transfer was performed in 22 cases, and a third in 2 (total of 69 procedures). Based on the observations of our study, fat grafting is a simple, effective and reproducible technique, with a high satisfaction rate and few disadvantages or complications. We demonstrated that the success of lipofilling is dependent on the treated aesthetic subunits of the face. The malar and lateral cheek regions seem to be highly favourable for fat grafting, unlike the upper and lower lips subunits. Composite procedures using orthognathic surgery and autologous fat provide the surgeon with an additional, more customisable option for patients with maxillo-mandibular malformations.