Age-related changes of the insular cortex and lateral ventricles: Conventional MRI volumetric measures

Preliminary data suggest that the insular region may be atrophied in patients with Alzheimer's disease when compared with healthy, age-matched control subjects. Therefore, normative data on age-related changes of the insular cortex were gathered and compared with age-related changes in the bodies of the lateral ventricles, which have been studied previously. Cerebrospinal fluid (CSF) volume of the lateral ventricles and insular cortical regions were measured on T1-weighted axial magnetic resonance images in 93 healthy subjects (age, 21 to 84 years). Age-related changes were found in the lateral ventricles (r = 0.57, p < 0.0001) and in the CSF insular space (r = 0.42, p < 0.0001). Increasing age accounted for a significant amount of the variance for the lateral ventricle (pc = 0.45, p < 0.0001), but not for the insula (pc = 0.15, p = 0.14). Although there was a continuous linear increase in lateral ventricular volume with age, the CSF insular space increased linearly until the fourth decade, then plateaued until the seventh decade, with a linear increase thereafter. These data suggest that age-related changes occur in the region of the insular cortex, but differ from age-related changes of the lateral ventricles.