MR imaging after aneurysmal subarachnoid hemorrhage and surgery: A long-term follow-up study

BACKGROUND AND PURPOSE: We assumed that patients with surgically treated an eurysmal subarachnoid hemorrhage (SAH) might have more lesions than those r evealed by CT that could be visible on MR images. METHODS: We conducted a retrospective study of a series of 147 patients wit h aneurysmal SAH who were treated surgically within 3 days of the onset of SAH. One hundred four patients (mean age, 48.8 years) underwent MR imaging studies 2.1 to 5.6 years (mean, 3.3 years) postoperatively. RESULTS: Eighty-four (81%) patients presented a total of 152 areas of incre ased signal intensity on T2-weighted images, consistent with infarction; 48 % of the patients had lesions in the frontal lobes, CT performed 3 months p ostoperatively revealed hypodense areas on the scans of only 57% of the pat ients and showed lesions in the frontal lobes of only 16% of the patients. CONCLUSION: Patients who undergo early surgery for aneurysmal SAH have more lesions than are revealed by CT. The difference is remarkable, especially in the frontal lobes.