Brain perfusion SPECT with Brodmann areas analysis in differentiating frontotemporal dementia subtypes

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Clinical diagnosis of Frontotemporal Dementia (FTD) subtypes faces challenges due to overlapping symptoms.
• Accurate differentiation of FTD subtypes is crucial for effective patient management and treatment.

Purpose of the Study:

• To evaluate the utility of brain perfusion (99m)Tc-HMPAO SPECT with Brodmann area (BA) mapping in differentiating FTD subtypes.
• To identify specific BAs that can distinguish between various FTD variants and related conditions like Progressive Supranuclear Palsy/Corticobasal Degeneration.

Main Methods:

• Utilized (99m)Tc-HMPAO SPECT imaging in 91 FTD patients, including behavioral variants (bvFTD), language variants (lvFTD - PNFA and SD), and PSP/CBD.
• Employed NeuroGam software for semi-quantitative perfusion evaluation in BAs and comparison with a normal database.
• Applied stepwise logistic regression analyses to identify discriminating BAs between patient groups.

Main Results:

• Specific BAs (e.g., 28L, 32R) differentiated bvFTD from lvFTD.
• Distinct BAs (e.g., 8R, 25R) discriminated bvFTD from SD and PNFA.
• Other BAs (e.g., 6L, 6R, 7R, 20L, 22R, 32R, 45R) were identified for differentiating between lvFTD, bvFTD, and PSP/CBD.

Conclusions:

• Brain perfusion SPECT with BA mapping serves as a valuable tool for differential diagnosis of FTD variants.
• This neuroimaging technique enhances diagnostic accuracy, particularly in atypical or uncertain FTD presentations.
• Identifying specific implicated brain areas through BA mapping aids in refining differential diagnoses within the FTD spectrum.