Pure superficial posterior cerebral artery territory infarction in The Lausanne Stroke Registry.

OBJECTIVE

To determine the patterns of clinical presentation, lesion topography, and etiology in patients with ischemic stroke limited to the superficial territory of the posterior cerebral artery (s-PCA).

METHODS

In the Lausanne Stroke Registry (LSR, 1983-1998), we determined the patterns of clinical presentation, lesion topography and mechanisms of stroke, among 117 patients with s-PCA infarction (s-PCAI) on brain imaging.

RESULTS

s-PCAIs accounted for 30.5 % of all PCA territory ischemic strokes. The presumed etiology was embolism in 64 (54.5 %) patients [cardiac in 51 (43.5 %) and arterial in 13 (11 %)], indeterminate in 38 (32 %), PCA atherothrombosis in 4 (3.4 %), migraine in 4 (3.4 %), other rare causes in 4 (3.4 %), and multiple potential sources of embolism in 3 (2.5 %). The clinical findings were hemianopsia in 78 (67 %), quadrantanopsia in 26 (22 %), and bilateral visual field defects in 8 (7 %). Motor, sensory, or sensorimotor deficits were detected in 14 (12 %), 8 (6.8 %), or 8 (6.8 %) patients, respectively. Neuropsychological dysfunction included memory impairment in 20 (17.5 %; with left [L], right [R], or bilateral [B] lesions in 15, 2, or 3 patients, respectively), dysphasia in 17 (14.5 %; L/B: 14/3), dyslexia with dysgraphia in 5 (4 %; L/B: 4/1), dyslexia without dysgraphia in 10 (8.5 %; L/B: 8/2), hallucinations in 12 (10 %; L/R/B: 5/5/2), visual neglect in 11 (9.5 %; L/R: 2/9), visual agnosia in 10 (8.5 %; L/B: 7/3), prosopagnosia in 7 (6 %; R/B: 4/3), and color dysnomia in 6 (5 %; L: 6).

CONCLUSIONS

s-PCAIs are uncommon, representing less than a third of all PCA infarctions. Although embolism is the main cause in 60 % of patients, identification of the emboli source is often not possible. In 1/3 of cases, the stroke mechanism cannot be determined. Neuropsychological deficits are frequent if systematically searched for.