Impaired quantitative cerebral blood flow in scleroderma patients

Systemic Sclerosis (SSc) is a multisystem disease characterised by proliferation of vascular tissue, obliterative microvascular lesions and diffuse organ fibrosis. Despite widespread vascular disease, Central Nervous System complaints are only infrequently reported and it is uncertain whether they merely derive from systemic complications or whether they may be also caused by a primary vascular process within the brain. Regional cerebral blood flow (rCBF) was quantitatively measured by the 133Xenon clearance technique in twenty-seven consecutive SSc patients without relevant systemic complications and with different severity of vascular involvement, as staged by nailfold capillary videomicroscopy (NCV). Absolute, percent, and asymmetry rCBF values were compared (z-statistics) with age- and sex-matched healthy controls. Cerebral MRI and Mini-Mental State Examination (MMSE) were also performed. Doppler sonography of neck vessels and Transcranial Doppler sonography (TCD) were performed in patients presenting rCBF reduction. Cerebral hypoperfusion was found in the 52% of patients, i.e.: in 33% of patients with the 'early' NCV pattern, in 56% of patients with the 'active' pattern, and in 67% of patients with the 'late' NCV pattern. Thirty percent were the MRIs showing focal and/or diffuse signal abnormalities in the white matter of both hemispheres with the highest rate (44%) in the 'late' NCV pattern. MMSE disclosed mild dementia in one patient in the 'late' NCV group and some mistakes in 6 more patients, in the 'active' or 'late' NCV groups, whereas TCD failed to find significant stenosis of Willis' arteries. Cerebral hypoperfusion is shown for the first time in a substantial part of SSc patients without either neurological symptoms or relevant systemic complications. It is suggested that the rCBF reduction might be related to the systemic scleroderma microangiopathy although, probably due to the paucity of connective tissue in cerebral vessels, the vast majority of patients remains in a subclinical phase.