Standardized image quality for ⁶⁸Ga-DOTA-TATE PET/CT

Area of Science:

• Nuclear Medicine
• Radiopharmaceuticals
• Oncology Imaging

Background:

• ⁶⁸Gallium labeled somatostatin analogues (⁶⁸Ga-DOTA-SSA) are crucial for neuroendocrine tumor (NET) management.
• The influence of patient size on ⁶⁸Ga-DOTA-SSA PET image quality remains understudied.
• Optimizing PET imaging protocols for varying patient sizes is essential for accurate diagnosis.

Purpose of the Study:

• To investigate the relationship between patient size and ⁶⁸Ga-DOTA-TATE PET image quality.
• To develop a patient-size-based radiotracer dosing strategy.
• To ensure consistent and diagnostic-quality PET imaging across diverse patient populations.

Main Methods:

• Prospective inclusion of 21 patients undergoing ⁶⁸Ga-DOTA-TATE PET/CT.
• Acquisition of whole-body PET/CT data in list mode with varying per-bed positions (1-6 mbp).
• Correlation of signal-to-noise ratio (SNRnorm) with anthropometric parameters (body mass, length, BMI, etc.).

Main Results:

• Patient body mass demonstrated the strongest correlation (R² = 0.6) with SNRnorm.
• Lesion detectability and SUV measurements were not significantly affected by reduced acquisition times (3-5 mbp).
• A signal-to-noise ratio (SNR) of 6.2 was identified as a threshold for moderate to good image quality.

Conclusions:

• Body mass is a reliable predictor of ⁶⁸Ga-DOTA-TATE PET image quality.
• A novel non-linear dose regimen, adjusted for body mass, can standardize PET image quality.
• This approach ensures diagnostic image quality for neuroendocrine tumor patients regardless of size.