ABSTRACT
BACKGROUND AND PURPOSE: Pilomyxoid astrocytoma (PMA) is a recently described variant of pilocytic astrocytoma (PA) with unique clinical and histopathologic characteristics. Because the histopathology of PMA is distinct from that of PA, we hypothesized that PMAs would display distinctive imaging characteristics. We retrospectively reviewed the imaging findings in a large number of patients with PMA to identify these characteristics. MATERIALS AND METHODS: CT and MR images, pathology reports, and clinical information from 21 patients with pathology-confirmed PMA from 7 institutions were retrospectively reviewed. CT and MR imaging findings, including location, size, signal intensity, hemorrhage, and enhancement pattern, were tabulated. RESULTS: Patients ranged in age from 9 months to 46 years at initial diagnosis. Sex ratio was 12:9 (M/F). Twelve of 21 (57%) tumors were located in the hypothalamic/chiasmatic/third ventricular region. Nine (43%) occurred in other locations, including the parietal lobe (2/21), temporal lobe (2/21), cerebellum (2/21), basal ganglia (2/21), and fourth ventricle (1/21). Ten (48%) tumors showed heterogeneous rim enhancement, 9 (43%) showed uniform enhancement, and 2 (9%) showed no enhancement. Five (24%) masses demonstrated intratumoral hemorrhage. CONCLUSION: This series expands the clinical and imaging spectrum of PMA and identifies characteristics that should suggest consideration of this uncommon diagnosis. One third of patients were older children and adults. Almost half of all tumors were located outside the typical hypothalamic/chiasmatic region. Intratumoral hemorrhage occurred in one quarter of patients. PMA remains a histologic diagnosis without definitive imaging findings that distinguish it from PA.
Subject(s)
Astrocytoma/classification , Astrocytoma/diagnosis , Brain Neoplasms/classification , Brain Neoplasms/diagnosis , Magnetic Resonance Imaging/methods , Tomography, X-Ray Computed/methods , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Infant , Internationality , Male , Middle Aged , Retrospective Studies , Young AdultSubject(s)
Gastric Lavage/methods , Hepatitis/etiology , Pneumatosis Cystoides Intestinalis/etiology , Sodium Bicarbonate/adverse effects , Diagnosis, Differential , Female , Follow-Up Studies , Gastric Lavage/adverse effects , Hepatitis/diagnosis , Humans , Iatrogenic Disease , Infant, Newborn , Jejunal Diseases/congenital , Jejunal Diseases/diagnosis , Male , Pneumatosis Cystoides Intestinalis/diagnostic imaging , Pregnancy , RadiographyABSTRACT
The cases of 107 paediatric patients aged 0-12 years were retrospectively reviewed. The patients presented with facial trauma and both plain radiographs and computed tomography (CT) scans had been ordered. Sixty-five per cent of facial fractures were missed in radiography, but revealed on CT; fractures of the maxilla, the zygoma and the orbit were most frequently missed in radiography. Pedestrian motor vehicle accidents were the most frequent cause of facial fractures (37%), followed by passenger motor vehicle accidents (22%). In contrast with other studies reporting the mandible as the most frequent facial fracture site, the most common fracture sites in this study, in descending order of frequency, were the orbit, the frontal bone and the maxilla.
