New asymptomatic ischemic lesions on diffusion-weighted imaging after cerebral angiography.

BACKGROUND AND PURPOSE: We investigated the frequency of new lesions on diffusion-weighted imaging (DWI) after conventional cerebral angiography (CAG) in acute stroke patients and associated factors.

METHODS: Fifty-six acute stroke patients with CAG and 55 stroke patients without CAG (controls) underwent DWI twice, within 48 h before and after CAG, and within 48 h and 7 days after onset, respectively. The frequency of new DWI lesions was then compared between the two groups. Next, we divided the CAG group patients into two groups according to the presence of new DWI lesions after CAG (Positive and Negative groups), and the factors associated with new DWI lesions were investigated by multivariate logistic regression analysis.

RESULTS: New DWI lesions were more often observed in the CAG group than the Control group (43% versus 31%, p=0.192). In the CAG group, mean fluoroscopy time was longer in the Positive group than the Negative group (26.5 min versus 14.9 min, p<0.001). Sensitivity and specificity analysis demonstrated a fluoroscopy time of 17 min to discriminate the Positive and Negative groups. Multivariate logistic regression analysis demonstrated that a fluoroscopy time of over 17 min was independent factor associated with new DWI lesions after CAG (OR, 9.4, 95% CI 1.8 to 48.6, p=0.0078).

CONCLUSION: New DWI lesions were more often seen in patients with CAG than without CAG. However, the difference in number of DWI abnormalities did not reach statistical significance. In CAG patients, fluoroscopy time appears to be an independent factor associated with new DWI lesions.