Would a thyroid scan and ultrasound together identify grave's disease?

No: A radioisotope 131i scan can show where iodine is picked up (usually throughout the whole gland). An ultrasound is useless. The diagnosis is based on elevated thyroid hormones T3 (liothyronine) and t4, suppressed TSH and, if necessary a marker of autoimmunity (usually a tpo ab).

Thyroid uptake/scan: Thyroid uptake and scan alone can differentiate grave's disease from other thyrotoxicosis. The study has two portions, the uptake measures the percentage of radio-iodine taken by the gland (10-30% is normal in usa) and the scan shows the radio-iodine distribution in the gland. Grave's typically results in elevated iodine uptake and uniform iodine distribution, often with a prominent pyramidal lobe.

Yes: Generally a blood test (TSH) and the thyroid scan are sufficient to identify grave's disease.

No: A thyroid scan can be helpful to determine whether hyperthyroidism was due to thyroiditis, an autonomous nodule, or graves. Usually an ultrasound is not necessary or helpful. Blood tests important.