This case involved a 42 year old man with mild traumatic brain injury (TBI) and multiple neuropsychiatric symptoms which persisted for a few years after the injury.  Despite his classical clinical picture for TBI and posttraumatic symptoms, initial CT and MRI scans of the brain showed no signs of atrophy.  A volumetric cross-sectional (one point in time) analysis performed using NeuroQuant® and NeuroGage® also showed no atrophy.  However, volumetric longitudinal (two points in time) analysis showed progressive atrophy in several brain regions.  This case illustrated in a single patient the principle discovered in multiple previous group studies, namely that the longitudinal design is more powerful than the cross-sectional design for finding atrophy in patients with TBI. 

Ross, DE, C Castelvecchi, AL Ochs (2013). Brain MRI volumetry in a single patient with mild traumatic brain injury. Brain Injury 27:634-636.  To view the PubMed citation of this paper, click here.  

Brain MRI volumetry in a single patient with mild traumatic brain injury.