Related Experiment Videos
False-positive V/Q scan mimicking massive pulmonary embolism.
1Department of Radiology, New York Medical College, Metropolitan Hospital, New York.
Clinical Nuclear Medicine
|January 1, 1992
Summary
A technical error involving inadvertent injection of Tc-99m MAA via a Swan-Ganz catheter can mimic pulmonary embolism on lung scans. Repeat scans after proper injection confirmed no actual embolism, highlighting the importance of recognizing this rare error.
Area of Science:
- Nuclear Medicine
- Radiology
- Medical Imaging
Background:
- False-positive lung scans can arise from various causes, though technical errors are seldom considered.
- Pulmonary embolism (PE) diagnosis relies heavily on radionuclide lung imaging, specifically perfusion scans.
Observation:
- A case report details inadvertent injection of Technetium-99m macroaggregated albumin (Tc-99m MAA) through a Swan-Ganz catheter.
- This technical error led to imaging findings that falsely suggested massive pulmonary embolism.
Findings:
- A repeat perfusion scan after correct peripheral vein injection demonstrated normal findings.
- The absence of typical clinical signs for PE and the unusual nature of the perfusion defects were key diagnostic clues.
Implications:
- This case underscores the need to consider technical errors, such as incorrect catheter injection, in the differential diagnosis of abnormal lung scans.
- Awareness of such misleading scenarios is crucial for accurate interpretation of radionuclide imaging and avoiding misdiagnosis of pulmonary embolism.