[Typical normal cases and normal cases with abnormal image pattern in every myocardial SPECT radiopharmaceutical]

Area of Science:

• Nuclear Medicine
• Cardiology
• Medical Imaging

Background:

• The Japanese Society of Nuclear Medicine and Cardiology formed a working group for cardiac nuclear medicine.
• Investigating normal myocardial SPECT findings is crucial for accurate diagnosis.

Purpose of the Study:

• To identify and characterize typical normal cases and normal cases with abnormal image patterns across various myocardial SPECT radiopharmaceuticals.
• To establish criteria for differentiating normal variants from actual pathologies.

Main Methods:

• Collected typical normal and normal-abnormal SPECT cases (T1, BMIPP, MIBG, MIBI, tetrofosmin) from 11 institutions.
• Summarized SPECT data acquisition parameters.
• Reviewed literature for discrimination criteria.

Main Results:

• Radiopharmaceutical patterns varied, with MIBG showing distinct normal and normal-abnormal patterns compared to others.
• Diaphragmatic attenuation, breast attenuation, and apical thinning were common normal variants in T1, BMIPP, MIBI, and tetrofosmin SPECT.
• Established a basis for distinguishing normal variations from true abnormalities.

Conclusions:

• Understanding normal variations in myocardial SPECT is essential for accurate interpretation.
• Specific radiopharmaceuticals like MIBG exhibit unique normal patterns.
• This work aids in refining diagnostic accuracy in cardiac nuclear medicine.