Brain Scintigraphy Demonstration of BBB Disruption After Cardiac Surgery

Background: We recently demonstrated BBB disruption after cardiac surgery using brain MRI studies. However, this technique is expensive, time consuming and cumbersome in postoperative patients.

99mTc-Diethylenetriaminepentaacetic acid (99mTc-DTPA) brain scintigraphy is another technique for the assessment of BBB disruption. This technique was never practiced before in post cardiac surgery patients.

Methods: three patients referred to coronary artery bypass grafting were assigned to undergo serial (99mTc-DTPA) brain scintigraphy evaluations. Designated brain scintigraphy examinations were performed preoperatively, on postoperative days 1 and 5. All these studies were preceded by evaluation of renal function-immediately after intravenous tracer injection and a whole body imaging for the assessment of capillary leak.

Results: BBB disruption was demonstrated on postoperative day 1 in all patients. This disruption underwent resolution on postoperative day 5. Location of the BBB disruption was confined to the parietal and frontal lobes. Renal function deterioration and capillary leak was demonstrated in all patients.

Conclusion: Brain scintigraphy can be used for the assessment of post cardiac surgery BBB disruption. Additional information that can be gained from this study is renal function and capillary leak assessment. We therefore suggest that brain scintigraphy will become the study of choice for the assessment of new treatments for the prevention of post cardiac surgery BBB disruption.