Masayuki Yamura

Usefulness of measurement of the temporal stem on magnetic resonance imaging in the diagnosis of frontotemporal dementia

Purpose: To investigate whether measurements of brain structures on routine magnetic resonance (MR) images can be used to distinguish between normal subjects and patients with frontotemporal dementia (FTD) or Alzheimers disease (AD). Material and Methods: MRI studies were performed on 30 patients with dementia (FTD, n = 15; AD, n = 15) and 15 age-matched controls. Width measurements, obtained at the corpus callosum, the cingulate gyri, the hippocampi, and the temporal stem of the anterior temporal lobes, were compared among FTD and AD patients and control subjects on oblique-coronal T2-weighted images. Results: The width of the temporal stem was significantly narrower in FTD than in AD patients and control subjects (6.3±1.3 mm, 7.8±1.1 mm, and 8.2±0.9 mm, respectively) (P<0.05), although there was some overlapping between AD and FTD patients. All patients whose temporal stem width was <6 mm had FTD. While the width of the corpus callosum, cingulate gyri, and hippocampi was significantly narrower in patients with AD and FTD than in the controls, there was no significant difference between the AD and FTD patients. Conclusion: The width of the temporal stem was significantly narrower in patients with FTD than in those with AD and controls. The described measurements can easily be obtained and may be useful for the diagnosis of FTD.

Evaluation of small hypothalamic hamartomas with 3D constructive interference in steady state (CISS) sequence

Hypothalamic hamartomas are relatively rare, non-neoplastic congenital malformations. With conventional MR images alone, small hypothalamic hamartomas may be difficult to diagnose because of artifacts from cerebrospinal fluid. We present the usefulness of three-dimensional constructive interference in steady state sequence for evaluating small hypothalamic hamartomas in three pediatric patients.