Evaluation of volumetric changes in differential diagnosis of brain atrophy and active hydrocephalus.

Despite a variety of diagnostic methods, differentiation of symptoms of normal pressure hydrocephalus from those of atrophic processes of the brain is still a difficult task. In the present study an attempt of non-invasive differential diagnosis of normal pressure hydrocephalus (NPH) and brain atrophy (BA) was presented using volumetric analysis of CT images of the head by means of VisNow proprietary software. The analysis was based on the number of voxels converted to the amount of cerebrospinal fluid (CSF) in the subarachnoid space, skull base casters, and the ventricular system. The results demonstrate that the mean volumes of CSF in these compartments in patients with NPH differed significantly from those in BA. Similarly, the mean volumes of CSF in the subarachnoid space and skull base casters in patients with BA differed significantly from those in NPH. Volumetric assessment presented in the paper by application of VisNow software seems useful in the evaluation of NPH and brain BA.