A history of monoparesis does not differentiate between superficial and small deep (Lacunar) infarction

On examination, acute monoparesis is usually caused by superficial infarction and only rarely by small deep (lacunar) infarction. In patients with transient neurological deficits, information about the clinical features can often be obtained only by history. The aim of this study was to investigate whether a history of monoparesis is also reliable in differentiating between superficial and small deep (lacunar) infarction. We therefore compared the site of infarction on computed tomography (CT) scans of 38 patients who had a history of monoparesis with that in 14 patients in whom monoparesis was documented by neurological examination. In the patients with a history of monoparesis 15 (40%) of the infarcts were superficial versus 13 (93%) of the infarcts in the patients with manifest monoparesis (odds ratio 0.05; 95% confidence interval 0.01-0.28; p = 0.002). The positive predictive value of a history of monoparesis in diagnosing superficial infarction was therefore only 0.40, whereas in manifest monoparesis it was 0.93. We conclude that a history of monoparesis does not reliably differentiate between superficial and small deep (lacunar) infarction, whereas monoparesis determined by neurological examination is highly specific for superficial infarction.