Iron Deposits in Periaqueductal Gray Matter Are Associated with Poor Response to OnabotulinumtoxinA in Chronic Migraine.

Previous studies have reported increased brain deposits of iron in patients with chronic migraine (CM). This study aims to determine the relation between iron deposits and outcome after treatment with OnabotulinumtoxinA (OnabotA). Demographic and clinical data were collected for this study through a prospective cohort study including 62 CM patients treated with OnabotA in the Hospital Clínico Universitario de Santiago de Compostela (Spain). Demographic and clinical variables were registered. Selected biomarkers in plasma during interictal periods (calcitonin gene-related peptide (CGRP) and pentraxin-3 (PTX3)) and neuroimaging changes (iron deposits in the red nucleus (RN), substantia nigra (SN), globus pallidus (GP), and periaqueductal gray matter (PAG), and white matter lesions (WML)) were determined. Subjects were classified in responders (≥50% reduction in headache days) or non-responders (<50%). Responders to treatment were younger (mean age difference = 12.2; 95% confidence interval (CI): 5.4-18.9, p = 0.001), showed higher serum levels of CGRP (≥50 ng/mL) and PTX3 (≥1000 pg/mL) and smaller iron deposits in the GP and PAG (mean difference = 805.0; 95% CI: 37.9-1572.1 µL, p = 0.040 and mean difference = 69.8; 95% CI: 31.0-108.6 µL, p = 0.008; respectively). Differences in PAG iron deposits remained significant after adjusting for age (mean difference = 65.7; 95% CI: 22.8-108.6 µL, p = 0.003) and were associated with poor response to OnabotA after adjustment for clinical and biochemical variables (odds ratio (OR) = 0.963; 95% CI: 0.927-0.997, p = 0.041). We conclude that larger PAG iron deposits are associated with poor response to OnabotA in CM.

IgG4-related Disease from Head to Toe.

Immunoglobulin G4 (IgG4)-related disease is a relatively recently proposed clinical-pathologic entity that is characterized by fibro-inflammatory lesions rich in IgG4-positive plasma cells and, often but not always, elevated serum IgG4 concentrations. IgG4-related disease was recognized as a systemic disease in 2003, when extrapancreatic manifestations were identified in patients with autoimmune pancreatitis. Since then, the disease has been reported as affecting virtually every organ system and has been identified in the biliary tree, salivary and lacrimal glands, periorbital tissues, lungs, lymph nodes, thyroid gland, kidneys, prostate gland, testicles, breasts, and pituitary gland. Its pathogenesis is poorly understood, but findings are consistent with both an autoimmune and an allergic disorder. Although definitive diagnosis requires histopathologic analysis, imaging plays an important role in demonstrating infiltration and enlargement of involved organs. Because of the systemic nature of the disease, imaging workup of IgG4-related disease should always include whole-body examinations to detect multiorgan involvement. Patients often present with subacute development of a mass in or diffuse enlargement of the affected organ, sometimes mimicking a neoplastic process. In every anatomic location, several inflammatory and neoplastic entities must be considered in the differential diagnosis. Because IgG4-related disease usually shows a marked response to corticosteroid therapy, radiologists should be familiar with its clinical and imaging manifestations to avoid a delay in diagnosis and unnecessary surgical interventions.

The spectrum of cystic masses of the pancreas: imaging features and diagnostic difficulties.

Cystic masses of the pancreas comprise a diverse group of pathologic entities ranging from pseudocysts to cystic tumors. Although their presentations may be similar, the appropriate treatment and patient management can differ greatly. There is an overlap in radiologic features, but the clinical context and some imaging findings are useful in differentiating among these entities; the differential diagnosis could be considerably reduced and it is generally possible to reach the correct diagnosis. In this article, we review imaging characteristics and radiologic patterns of both common and uncommon cystic masses of the pancreas. An algorithmic approach for the management of cystic pancreatic lesions is proposed.