Dynamic Single-Section Contrast CT Measures Cerebral Blood Flow in Acute Intracerebral Hemorrhage
Objective: Investigate presence of reduced rCBF in hyperacute ICH using contrast CT. Background: Reduced rCBF has been reported in ICH. Its extent and precise pattern, however, remain uncertain. Hyperacute ICH patients are difficult to study as they are often critically ill. Dynamic CT is rapid, easily performed and offers superior spatial resolution to PET, SPECT and MRI. Methods: CT scans were performed within 12 hrs of symptom-onset in 3 acute ICH patients during high-speed injection of standard iodinated contrast via the antecubital vein. Two 10 mm thick target sections were imaged continuously for 60 sec. After ICH volumes were measured, regions of interest (ROIs) for determination of rCBF were selected in serially expanding 2 mm sections around each hematoma and compared to similarly measured expanding 2 mm sections around a hypothetical hematoma in the contralateral hemisphere. Results: Three patients were studied at 3, 8 and 11 hrs post symptom-onset respectively. Hematoma locations were: putamen (9 ml) frontal lobe (64 ml) and thalamus (10 ml). Regional CBF (ml/min/100g) was decreased in the rim of tissue immediately adjacent to the hematomas (4.2, 2.1, 5.5, respectively) and increased in serially measured concentric ROIs as they expanded around each hematoma. When values obtained 2 and 8 mm from the hematoma periphery were compared, rCBF increased by 440%, 582%, 454%, respectively (graph), compared to 71%, 128%, 4% in the opposite hemisphere. Conclusion: Single-section dynamic CT is a promising technique for measuring rCBF around acute intracerebral hematomas. There appears to be a rim of reduced rCBF surrounding these hematomas. Further study is necessary to determine its clinical significance.