Semi-quantitative analysis of visually normal ¹²³I-FP-CIT across three large databases revealed no difference between...

Area of Science:

• Nuclear Medicine
• Radiopharmaceutical Imaging
• Neuroscience

Background:

• ¹²³I-FP-CIT SPECT scans are crucial for assessing dopaminergic degeneration.
• Establishing reliable reference databases for specific binding ratios (SBR) is essential for accurate diagnosis.
• Visually normal scans from various patient groups and healthy volunteers are compared to validate reference data.

Purpose of the Study:

• To demonstrate the equivalence of SBR values from visually normal ¹²³I-FP-CIT SPECT scans to existing reference databases.
• To validate the use of patient-derived normal scans for creating a reference database.
• To investigate the influence of age and gender on SBR values.

Main Methods:

• Analysis of SBR values from three groups: suspected Parkinsonism (ScanOnlyDB), no dopaminergic degeneration (NoDG5YearsDB), and healthy volunteers (HvDB).
• General linear model (GLM) analysis incorporating age and gender as independent variables.
• Post-reconstruction harmonization and pairwise comparison of databases, including comparison with published data (SiemensDB, ENC-DAT).

Main Results:

• SBR values showed no significant difference in dispersion parameters or coefficients of variation between databases.
• SBR significantly decreased with age across all groups, with a notable age-gender interaction in ScanOnlyDB.
• GLM estimates from ScanOnlyDB were comparable to existing commercial and published databases, except for the age-gender interaction.

Conclusions:

• SBR distribution in visually normal scans aligns with existing reference databases, supporting the creation of expert-curated databases.
• A significant, rarely described age-gender interaction influencing SBR was identified.
• The proposed post-reconstruction harmonization method enhances the utility of semi-quantitative analysis in SPECT imaging.