Assessment of vasogenic edema in eclampsia using diffusion imaging

We qualitatively assessed the regional distribution of vasogenic edema in a case of postpartum eclampsia. Although diffusion-weighted imaging showed no abnormalities, bilateral high signal was seen on T2-weighted images and apparent diffusion coefficient (ADC) maps. ADC of 1.45 ± 0.10 mm²/s × 10^–3 for the posterior cerebral artery (PCA) territory and 1.22 ± 0.12 mm²/s × 10^–3 for the watershed areas were significantly higher than those in the territories of the anterior (0.85 ± 0.07 mm²/s × 10^–3) and middle cerebral (0.79 ± 0.06 mm²/s × 10^–3)arteries (P < 0.05). The predilection of ADC changes within the PCA territory and in a previously undescribed watershed distribution supports the hypothesis that vasogenic edema in eclampsia is due to hypertension-induced failure of vascular autoregulation. Received: 8 July 1999 Accepted: 25 April 2000