Presentation
Four year history of increasing cognitive and functional decline, with prominent difficulties in speech, dressing himself, memory and activities of daily living.
Patient Data
MRI non contrast Encephalopathy protocol
No focal signal abnormality identified. Significant bilateral parietal lobe volume loss, slightly more prominent on the left, and correlated with local reduced perfusion in those areas. Mesial temporal lobes appear normal. No evidence of restricted diffusion.
No extra-axial collections or mass are evident.
Conclusion: The presence of bilateral parietal lobe volume loss in the this age group and clinical setting favors Alzheimer's disease as the most likely diagnosis.
These studies show moderate hypoperfusion of the prefrontal lobes. There is also a small focal zone of severe hypoperfusion located at the left superior parietal lobe. Left cerebral hemisphere perfusion is generally mildly reduced compared to right possibly due to diaschisis from this zone of focal intense hypoperfusion. There is also an unexpected increase in perfusion seen at the left anterior temporal pole mesial cortex. Perfusion of the brainstem and cerebellum and basal ganglia is normal.
Case Discussion
The most striking feature of the initial clinical presentation was expressive dysphasia. He also initially developed visuoconstructional difficulties, later becoming increasingly ataxic.
The imaging is a good demonstration of parietal volume loss. The intraparietal sulci are widened. There is pronounced volume loss of the superior parietal lobules. The medial temporal lobes are of normal appearance. There are no significant chronic small vessel ischemic changes.
The features, both clinical and on imaging, are characteristic of early-onset Alzheimer disease / posterior cortical atrophy.