In patients with coronary artery disease and left ventricular dysfunction, quantified sestamibi activity 1 hour after rest injection parallels redistribution 201Tl activity after a resting injection, suggesting that uptake and subsequent handling of sestamibi are more complex than can be explained by a pure flow tracer with no redistribution. Quantitative analysis of regional activities of both 201Tl and sestamibi after resting injections can differentiate viable from nonviable myocardium, and the two agents comparably predict reversibility of significant regional wall motion abnormalities after revascularization in such patients to a similar degree.

Visual evidence of wall thickening by poststress ECG-gated SPECT sestamibi imaging in the territory of a stress-induced perfusion defect correlates highly with stress defect reversibility on rest imaging and may obviate the need to perform rest imaging, thereby potentially reducing the time and cost involved in myocardial perfusion imaging. The absence of visually apparent wall thickening, however, underestimates the prevalence of stress defect reversibility on rest imaging; in such instances, rest imaging must be performed to differentiate ischemia from infarction in the territory of a stress perfusion defect.

Surgical localization of osteoid osteomas is a major problem in the diagnosis and therapy of this lesion. Visual, tactile, and radiographic localization is often equivocal and as a consequence incomplete excision of the tumor, or excessive removal of bone may result. We performed magnification intraoperative bone scintigraphy using a portable gamma camera and a radioactive pointer in six patients with osteoid osteoma. Accurate localization and complete removal of the tumor was achieved in all six with only minimal delays in the surgical procedure. The advantages of this technique and recommendations for its use are discussed.