Pediatric CNS Inflammation and Infection: A Review of Immunopathology and Radiology.

The innate and adaptive immune systems are critical in defense against pathogens and ensuring homeostasis. The central nervous system (CNS) was initially considered to be impermeable to immune cells due to the blood-brain barrier. However, this has now been debunked, with modern research delineating immune cell trafficking within the CNS, ensuring constant immune surveillance. However, these defenses may be breached in infections, which trigger an inflammatory cascade causing tissue damage. In addition, autoimmune conditions and genetic mutations may also lead to sustained proinflammatory molecule release causing significant CNS damage. Ensuing brain injury from most immune triggers is varied but may be associated with common patterns by virtue of a shared immune driver. MRI plays an important role in identifying these conditions and further enables understanding of their pathophysiology as well as their spatial predilection in the brain. In this review, we discuss basic immunology, the major CNS barriers to infections as well as the current understanding of selected pediatric infections and inflammatory processes.

Morphological and Advanced Imaging of Epilepsy: Beyond the Basics.

The etiology of epilepsy is variable and sometimes multifactorial. Clinical course and response to treatment largely depend on the precise etiology of the seizures. Along with the electroencephalogram (EEG), neuroimaging techniques, in particular, magnetic resonance imaging (MRI), are the most important tools for determining the possible etiology of epilepsy. Over the last few years, there have been many developments in data acquisition and analysis for both morphological and functional neuroimaging of people suffering from this condition. These innovations have increased the detection of underlying structural pathologies, which have till recently been classified as "cryptogenic" epilepsy. Cryptogenic epilepsy is often refractory to anti-epileptic drug treatment. In drug-resistant patients with structural or consistent functional lesions related to the epilepsy syndrome, surgery is the only treatment that can offer a seizure-free outcome. The pre-operative detection of the underlying structural condition increases the odds of successful surgical treatment of pharmacoresistant epilepsy. This article provides a comprehensive overview of neuroimaging techniques in epilepsy, highlighting recent advances and innovations and summarizes frequent etiologies of epilepsy in order to improve the diagnosis and management of patients suffering from seizures, especially young patients and children.

Mid-Esophageal Diverticulum Mimicking an Aortic Aneurysm on Chest Radiography.

BACKGROUND: Mid-esophageal region is an uncommon location of esophageal diverticula, a condition usually diagnosed in elderly individuals. CASE REPORT: We report a case of an elderly male with incidental finding of mediastinal lesion, which was initially thought to be an aortic aneurysm. Further evaluation demonstrated a mid-esophageal diverticulum at the level of the carina. We present patient's medical history and imaging, followed by a discussion on symptoms and management. CONCLUSIONS: Knowledge of benign conditions that might mimic a mediastinal vascular pathology is important for therapeutic and prognostic reasons, as they are often managed conservatively.

Susceptibility-weighted angiography and diffusion-weighted imaging in posterior reversible encephalopathy syndrome - Is there an association between hemorrhage, cytotoxic edema, blood pressure and imaging severity?

PURPOSE: To assess the significance of association and possible correlation between hemorrhage, cytotoxic edema, blood pressure and imaging severity in posterior reversible encephalopathy syndrome (PRES). MATERIALS AND METHODS: This retrospective study included the medical and imaging records of 35 consecutive patients with PRES. The clinical data analysis included the highest recorded blood pressure (BP) on the day of the ictus, MRI including spin-echo echo planar diffusion-weighted imaging (DWI), susceptibility weighted angiography (SWAN) and conventional sequences. The presence of hemorrhage and cytotoxic edema was evaluated for the significance of correlation and association with each other and with blood pressure and imaging severity. RESULTS: On MR imaging, hemorrhage was found in 25.7%, and cytotoxic edema in 20% of patients. There was no statistically significant association of hemorrhage (P=0.403) and cytotoxic edema (P=0.162) with BP in contrast to significant association of hemorrhage (P<0.001) and cytotoxic edema (P=0.011) with imaging severity and with each other (P=0.002). There was a significant correlation of hemorrhage (Cramer's V - 0.672) and cytotoxic edema (Cramer's V - 0.506) with imaging severity and with each other (Cramer's V - 0.523). CONCLUSION: The extent of imaging severity in PRES showed significant association and correlation with hemorrhage and cytotoxic edema. There was no statistically significant association of blood pressure with imaging severity, hemorrhage, and cytotoxic edema. Further prospective studies are needed to elucidate the pathophysiological mechanisms and their correlation with imaging findings in PRES.

Disseminated peritoneal leiomyomatosis: a rare cause of enigmatic peritoneal masses.

Disseminated peritoneal leiomyomatosis (DPL) is an unusual extrauterine form of leiomyoma that has been found to coexist with its intrauterine counterpart in individuals who have previously undergone laparoscopic myomectomy. The presence of extrauterine masses with the density of smooth muscle on CT imaging and/or with a low signal intensity similar to that of smooth muscle on T 2 weighted MRI in a patient presenting with associated intrauterine leiomyoma and/or a history of previous laparoscopic myomectomy suggests the possibility of DPL. Imaging studies help in diagnosing and delineating the location and extent of the lesion and also follow-up the masses to look for sarcomatous transformation. Here we report the case of a 43-year-old female who presented initially with right lower quadrant pain. Her CT scan and MRI demonstrated a fundal fibroid with multiple intraperitoneal soft tissue masses of similar appearance and contrast enhancement in the sigmoid mesocolon, the left paracolic gutter and adjacent to the ascending colon. The suspected diagnosis of DPL was confirmed during abdominal hysterectomy, bilateral salphingo-oophorectomy and excision of peritoneal masses.