Increased risk of pseudoprogression among pediatric low-grade glioma patients treated with proton versus photon radiotherapy.

Background: Pseudoprogression (PsP) is a recognized phenomenon after radiotherapy (RT) for high-grade glioma but is poorly characterized for low-grade glioma (LGG). We sought to characterize PsP for pediatric LGG patients treated with RT, with particular focus on the role of RT modality using photon-based intensity-modulated RT (IMRT) or proton beam therapy (PBT).

Methods: Serial MRI scans from 83 pediatric LGG patients managed at 2 institutions between 1998 and 2017 were evaluated.

Embryonal Tumor with Multilayered Rosettes, C19MC-Altered: Clinical, Pathological, and Neuroimaging Findings.

Background And Purpose: Embryonal tumor with multilayered rosettes (ETMR), C19MC-altered, is a recently described, rare central nervous system tumor. To our knowledge, the imaging findings of this tumor have not been systematically evaluated in the neuroradiology literature. We present here the clinical, radiological, and pathological correlation of a case series of this very rare tumor, including the full range of anatomic compartment presentations (supratentorial, infratentorial, and spinal).

Phase-contrast cerebrospinal fluid flow magnetic resonance imaging in qualitative evaluation of patency of CSF flow pathways prior to infusion of chemotherapeutic and other agents into the fourth ventricle.

Purpose: Nuclear medicine studies have previously been utilized to assess for blockage of cerebrospinal fluid (CSF) flow prior to intraventricular chemotherapy infusions. To assess CSF flow without nuclear medicine studies, we obtained cine phase-contrast MRI sequences that assess CSF flow from the fourth ventricle down to the sacrum.

Methods: In three clinical trials, 18 patients with recurrent malignant posterior fossa tumors underwent implantation of a ventricular access device (VAD) into the fourth ventricle, either with or without simultaneous tumor resection.

Progression-free survival of children with localized ependymoma treated with intensity-modulated radiation therapy or proton-beam radiation therapy.

Background: The treatment for childhood intracranial ependymoma includes maximal surgical resection followed by involved-field radiotherapy, commonly in the form of intensity-modulated radiation therapy (IMRT). Proton-beam radiation therapy (PRT) is used at some centers in an effort to decrease long-term toxicity. Although protons have the theoretical advantage of a minimal exit dose to the surrounding uninvolved brain tissue, it is unknown whether they have the same efficacy as photons in preventing local recurrence.

Palliative reirradiation for progressive diffuse intrinsic pontine glioma.

Objective: Diffuse intrinsic pontine gliomas (DIPGs) are highly aggressive tumors and have a poor prognosis. Nearly all patients experience disease progression after definitive treatment, accompanied by severe neurologic deficits and morbidity. Here, we report a series of patients treated with reirradiation for palliation of symptoms.

Rosai-Dorfman disease in neuroradiology: imaging findings in a series of 10 patients.

Objective: Rosai-Dorfman disease is a rare disorder characterized histologically by lymphatic sinus dilatation due to histiocyte proliferation. Our goal was to describe the CT, MRI, and (18)F-FDG (FDG) PET findings in a series of patients with this diagnosis.

Materials And Methods: We retrospectively reviewed the imaging studies of 10 patients with pathologically confirmed Rosai-Dorfman disease who were treated in our institution between January 2004 and December 2007.

Imaging and spectroscopic findings in meningioangiomatosis.

Meningioangiomatosis (MA) is an uncommon brain tumor. The role of imaging techniques is underscored in cases where the tumor location makes resection (or even biopsy) dangerous. We report the case of a child with an MA tumor located deep in the right sylvian fissure.

Neuroimaging of pediatric diseases.

Imaging of the pediatric brain is challenging. Knowledge of the normal anatomy and appearance of the developing brain at a given age is critical in identifying abnormalities. Brain malformations had been in the domain of the neuropathologist, but with advanced neuroimaging they can be defined in vivo.

A multi-center 1H MRS study of the AIDS dementia complex: validation and preliminary analysis.

Purpose: To demonstrate the technical feasibility and reliability of a multi-center study characterizing regional levels of the brain metabolite ratios choline (Cho)/creatine (Cr) and myoinositol (MI)/Cr, markers of glial cell activity, and N-acetyl aspartate (NAA)/Cr, a marker of mature neurons, in subjects with AIDS dementia complex (ADC).

Materials And Methods: Using an automated protocol (GE PROBE-P), short echo time spectra (TE = 35 msec) were obtained at eight sites from uniformly prepared phantoms and from three brain regions (frontal white matter, basal ganglia, and parietal cortex) of normal volunteers and ADC and HIV-negative subjects.

Results: A random-effects model of the phantom and volunteer data showed no significant inter-site differences.