ASYMMETRY OF INTRACRANIAL HEMODYNAMICS AS AN INDICATOR OF MASS EFFECTIN ACUTE INTRACEREBRAL HEMORRHAGE - A TRANSCRANIAL DOPPLER STUDY

Background and Purpose Hematoma volume is an important determinant of outcome and predictor of clinical deterioration in patients with intra cerebral hemorrhage. In many cases, worsening results from herniation due to compartmentalized pressure gradients. We used transcranial Dopp ler sonography (TCD) to assess the impact of hematoma volume on symmet ry of intracranial hemodynamics in patients with acute intracerebral h emorrhage. The goal was to evaluate TCD as a noninvasive method for mo nitoring compartmentalized mass effect. Methods TCD was performed an a verage of 1.1 days (range, 0 to 3 days) after onset in 30 patients wit h supratentorial intracerebral hemorrhage. Hematoma, hematoma+edema, a nd intraventricular hemorrhage volumes were calculated from admission CT scans using computerized planimetry and were compared with combined TCD values from the middle cerebral and internal carotid arteries. Re sults Ipsilateral pulsatility indexes were consistently elevated and m ean velocities consistently depressed when intracerebral hemorrhage vo lumes exceeded 25 mL. Compared with patients with small hemorrhages, t hose with large hemorrhages (greater than or equal to 25 mL, n=10) had significantly higher ipsilateral pulsatility indexes (1.72 versus 1.1 3, P<.0001) and higher ratios of ipsilateral-to-contralateral pulsatil ity (1.29 versus 1.06, P=.001). The ratio of ipsilateral-to-contralate ral mean velocity was similarly reduced in patients with large versus small hemorrhages (0.87 versus 1.06, P=.01), but this effect was less pronounced. In a multiple regression analysis, ipsilateral and contral ateral pulsatility indexes correlated primarily with intraventricular hemorrhage volume (P<.001), whereas the ratio of ipsilateral-to-contra lateral pulsatility correlated with total hemispheric lesion (hematoma +edema) volume (P=.003).Conclusions Asymmetry of intracranial hemodyna mics as assessed by TCD occurs when intracerebral hemorrhage volumes e xceed 25 mt. Alterations of pulsatility index reflect intracranial les ion volume more reliably than mean velocity. Although pulsatility is s trongly influenced by the presence of intraventricular blood, elevated ratios of ipsilateral-to-contralateral pulsatility correlate primaril y with hemispheric lesion volume and may reflect compartmentalized int racranial pressure gradients.