Internal Auditory Canal Diverticula among Pediatric Patients: Prevalence and Assessment for Hearing Loss and Anatomic Associations.

BACKGROUND AND PURPOSE: Internal auditory canal diverticula are focal lucencies along the anterior-inferior aspect of the internal auditory canal fundus. Studies in adults report conflicting data on the etiology and clinical relevance of this finding. We would expect a pediatric study to help elucidate the significance of internal auditory canal diverticula. The primary goals of this study were to determine the temporal bone CT prevalence of diverticula among pediatric patients and to assess possible hearing loss and anatomic associations. MATERIALS AND METHODS: For this retrospective study including 283 pediatric temporal bone CTs, 4 neuroradiologists independently assessed for diverticula. Discrepancies were resolved by consensus. One neuroradiologist assessed for an enlarged vestibular aqueduct, labyrinthine dysplasia, cochlear cleft, and otospongiosis. Patient demographics, audiologic data, and pertinent clinical history were recorded. One-way analysis of variance and the Fisher exact test were used to assess possible associations between diverticula and specific patient characteristics. RESULTS: Diverticula were observed in 42/283 patients (14.8%) and were more commonly bilateral. There was no significant association with age, sex, hearing loss, enlarged vestibular aqueduct, labyrinthine dysplasia, or cochlear cleft. A statistically significant association was observed with otospongiosis (P = .013), though only 1 study patient had this disease. CONCLUSIONS: Internal auditory canal diverticula are a common finding on pediatric temporal bone CT. In the absence of clinical or imaging evidence for otospongiosis, diverticula likely fall within the range of a normal anatomic variation. Familiarity with these findings may prevent neuroradiologists from recommending unnecessary additional testing in pediatric patients with isolated internal auditory canal diverticula.

Increased Notching of the Corpus Callosum in Fetal Alcohol Spectrum Disorder: A Callosal Misunderstanding?

BACKGROUND AND PURPOSE: In the medicolegal literature, notching of the corpus callosum has been reported to be associated with fetal alcohol spectrum disorders. Our purpose was to analyze the prevalence of notching of the corpus callosum in a fetal alcohol spectrum disorders group and a healthy population to determine whether notching occurs with increased frequency in the fetal alcohol spectrum disorders population. MATERIALS AND METHODS: We performed a multicenter search for cases of fetal alcohol spectrum disorders and included all patients who had a sagittal T1-weighted brain MR imaging. Patients with concomitant intracranial pathology were excluded. The corpus callosum was examined for notches using previously published methods. A χ2 test was used to compare the fetal alcohol spectrum disorders and healthy groups. RESULTS: Thirty-three of 59 patients with fetal alcohol spectrum disorders (0-44 years of age) identified across all centers had corpus callosum notching. Of these, 8 had an anterior corpus callosum notch (prevalence, 13.6%), 23 had a posterior corpus callosum notch (prevalence, 39%), and 2 patients demonstrated undulated morphology (prevalence, 3.4%). In the healthy population, the anterior notch prevalence was 139/875 (15.8%), posterior notch prevalence was 378/875 (43.2%), and undulating prevalence was 37/875 (4.2%). There was no significant difference among the anterior (P = .635), posterior (P = .526), and undulating (P = .755) notch prevalence in the fetal alcohol spectrum disorders and healthy groups. CONCLUSIONS: There was no significant difference in notching of the corpus callosum between patients with fetal alcohol spectrum disorders and the healthy population. Although reported to be a marker of fetal alcohol spectrum disorders, notching of the corpus callosum should not be viewed as a specific finding associated with fetal alcohol spectrum disorders.

Does MR perfusion imaging impact management decisions for patients with brain tumors? A prospective study.

BACKGROUND AND PURPOSE: MR perfusion imaging can be used to help predict glial tumor grade and disease progression. Our purpose was to evaluate whether perfusion imaging has a diagnostic or therapeutic impact on clinical management planning in patients with glioma. MATERIALS AND METHODS: Standard MR imaging protocols were interpreted by a group of 3 NRs in consensus, with each case being interpreted twice: first, including routine sequences; and second, with the addition of perfusion imaging. A multidisciplinary team of treating physicians assessed tumor status and created hypothetical management plans, on the basis of clinical presentation and routine MR imaging and then routine MR imaging plus perfusion MR imaging. Physicians' confidence in the tumor status assessment and management plan was measured by using Likert-type items. RESULTS: Fifty-nine consecutive subjects with glial tumors were evaluated; 50 had known pathologic diagnoses. NRs and the treatment team agreed on tumor status in 45/50 cases (κ = 0.81). With the addition of perfusion, confidence in status assessment increased in 20 (40%) for NRs and in 28 (56%) for the treatment team. Of the 59 patient-care episodes, the addition of perfusion was associated with a change in management plan in 5 (8.5%) and an increase in the treatment team's confidence in their management plan in 34 (57.6%). NRs and the treatment team found perfusion useful in most episodes of care and wanted perfusion included in future MR images for >80% of these subjects. CONCLUSIONS: Perfusion imaging appears to have a significant impact on clinical decision-making and subspecialist physicians' confidence in management plans for patients with brain tumor.