Spinal dementia: Don't miss it, it's treatable.

Background & purpose: Around 5% of dementia patients have a treatable cause. To estimate the prevalence of two rare diseases, in which the treatable cause is at the spinal level.

Methods: A radiology information system was searched using the terms CT myelography and the operation and classification system (OPS) code 3-241. The clinical charts of these patients were reviewed to identify patients with a significant cognitive decline.

Results: Among 205 patients with spontaneous intracranial hypotension (SIH) and proven CSF leaks we identified five patients with a so-called frontotemporal brain sagging syndrome: Four of those had CSF venous fistulas and significantly improved by occluding them either by surgery or transvenous embolization. Another 11 patients had infratentorial hemosiderosis and hearing problems and ataxia as guiding symptoms. Some cognitive decline was present in at least two of them. Ten patients had ventral dural tears in the thoracic spine and one patient a lateral dural tear at C2/3 respectively. Eight patients showed some improvement after surgery.

Discussion: It is mandatory to study the (thoracic) spine in cognitively impaired patients with brain sagging and/ or infratentorial hemosiderosis on MRI. We propose the term spinal dementia to draw attention to this region, which in turn is evaluated with dynamic digital subtraction and CT myelography.