Antoun Boulos & Viet Tran 65yo female presents after tripping on a banana skin, hitting her head and losing consciousness for < 1min with return to baseline mentation on arrival. No focal neurology but has a distant history of minor stroke without residual deficit but is on anticoagulation. A CT Brain was ordered... |
Limited (4 slice) non contrast CT Brain (limited due to lack of technical ability to upload the whole set). Within these limited views there is no obvious midline shift. There is mild atrophy, enlarged lateral ventricles (symmetrical) with no boney or soft tissue abnormality.
There are symmetrical hyperdense (white) paraventricular and posterior fossa lesions. Signficiantly, within the constraints of a non-contrast CT, there does not appear to be any surrounding oedema.
If we are thinking about blood, the symmetrical nature and multiple areas would suggest that this does not represent blood - nor the clinical findings of a person who has returned to 'baseline'.
Impression
No obvious acute intracranial pathology. There is however symmetrical hyperdense (white) paraventricular and posterior fossa lesions without surrounding oedema and therefore suggesting that this is not acute, likely incidental in nature.
So what is your diagnosis?
Fahr disease (familial cerebral ferrocalcinosis)
- Congenital (autosomal dominant) disorder characterised by abnormal calcium deposition/atrophy of the basal ganglia, cerebral and cerebellar cortices
- Onset IS age dependent (typically 4th/5th decade of life - CT may be negative in patients under the age of 55)
- RARE, <1 in 1,000,000!
Symptoms
- Asymptomatic, even with advanced disease on neuro-imaging
- Seizures, Extra-pyramidal Symptoms, speech impairment
- Neuropsychiatric manifestations: behavioural changes, psychoses, dementia.
Pathogenesis
- Calcification develops within the vessel wall, extending to the perivascular space then into adjacent neurons
- Progressive mineralisation tends to compress blood vessels, thus impairing blood flow, tissue damage and further calcification
Diagnostic criteria
- Bilateral calcification of basal ganglia & other regions, on neuroimaging
- Progressive neurological dysfunction or neuropsychiatric manifestations
- Typical presentation in 4th/5th decade of life
- AD inheritance, strong family history
- Exclude other causes
- Biochemical (calcium/phosphate metabolism)
- Systemic illnesses (vasculitidies)
- Mitochondrial disorders
- Infectious/toxic syndromes
Treatment
- None if asymptomatic
- Symptom control
- Anti-epileptics
- Mood Stabiliser
Reference
Saleem S1, Aslam HM, Anwar M, Anwar S, Saleem M, Saleem A, Rehmani MA. Fahr's syndrome: literature review of current evidence. Orphanet J Rare Dis. 2013 Oct 8;8:156.