Sentinel lymph node mapping of the colon and stomach using lymphoseek in a pig model.

Background: Lymphoseek is a radiopharmaceutical designed for sentinel lymph node (SLN) mapping. The purpose of this study was to compare Lymphoseek colon and gastric pharmacokinetics with filtered [(99m)Tc]sulfur colloid (fTcSC).

Methods: Eight anesthetized pigs received an endoscopic injection of Lymphoseek or fTcSC in the stomach and colon.

Chronic pulmonary thromboembolism: detection of regional hypoperfusion with CT.

Purpose: To study the relationship of regional hypoperfusion and areas of decreased lung attenuation on computed tomographic (CT) scans of patients with chronic pulmonary thromboembolism.

Materials And Methods: Preoperative CT scans of five patients (four men and one woman, aged 29-72 years) with chronic pulmonary thromboembolism were reviewed and compared with axial single photon emission CT (SPECT) perfusion scans obtained at similar levels. Regions of varying attenuation and perfusion were scored on a three-point scale.

Technetium-99m labeled micro aerosol "Pertechnegas". A new agent for ventilation imaging in suspected pulmonary emboli.

In this preliminary study, four patients suspected of having pulmonary emboli underwent ventilation imaging after inhaling approximately 1 mCi (37 MBq) of Tc-99m Pertechnegas (micro aerosol carbon particles labeled with Tc-99m) in five breaths or less. Planar images in multiple projections were recorded for preset counts. A final posterior image was acquired to evaluate residual lung background activity.

A modeling analysis of rest-stress and stress-rest injection sequences in performing thallium-201 myocardial perfusion scintigraphy.

A new thallium-201 stress testing protocol is proposed in which rest images are obtained prior to stress images. The advantages of the new protocol are that it saves time and requires no special diet or activity restriction between imaging sets. A potential problem from reversing the standard imaging sequence is decreased sensitivity to stress perfusion defects owing to background counts from the rest image.