Radioactive Iodine Treatment, Any experiences to share? Options

[J T]

Our cat Stormy has been diagnosed with hyperthyroidism, and after reviewing all the options, we have decided to have her treated with radioactive Iodine-131. The surgery just seemed to have too much of a risk of leaving her hypothyroid/hypocalcemic(plus the risk of anesthesia in general for a 13-year old), and treating her with pills or topical every day just didn't seem like a good choice. Has anyone had this done and have any experience to share?

She is on methimazole(Tapazole) topical gel for the couple of weeks until her treatment; she goes in to the clinic for workups on May 8, and will receive her treatment on May 12. Prayers very much appreciated.