Thursday, April 09, 2009

MUGA scan report

Sherrie had the MUGA scan this afternoon. From my perspective, it went fine, but Sherrie had to hold her arms over her head while they were taking pictures, which made her sore. (She was lying down on the detector table.)

Briefly: a MUGA scan is a "multi-gated analysis" (or something similar) in which the blood is infused with Technetium-99m (a gamma source). The detector is prompted by an EKG to count photons (gamma rays) at various parts of the heart's cycle (eight times per cycle). The system integrates the counts for about 5-10 minutes per scan. The system makes the scans from three different angles, constructing a 3D model of the beating heart. From the data, the system can measure the heart's efficiency. A healthy heart is about 60 percent efficient, meaning that it "moves" about 60 percent of the blood in the ventricles per heartbeat.

The technician was nice to us and talked to us about the procedure and the pictures in real-time. As soon as he started taking the pictures, we noticed a black spot right on top of Sherrie's heart. It showed up in the scans from all three angles. At first, the technician thought that Sherrie must have had some metal on her body or inside her. He later decided that it was coming from the expander which was placed inside Sherrie's chest. At the end, we looked at the detailed pictures and could see a perfect ring about 1/4 inch in diameter, lying in her skin above the heart. We're still not sure what it is. Presumably there is no metal on the expander, but I'm not really sure. Perhaps it is some other material which absorbs the gamma-rays.

Sherrie's heart efficiency was about 68 percent, which is better than the expected "threshold" of 60 percent. Assuming nothing untoward comes up in the more detailed analysis, we believe she should be good to go for chemo.

The technician showed us "moving pictures" of the heart's beating cycle. It was really cool.

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