Multi-Tube-Voltage vBMD Measurement via Dual-Branch Frequency Balancing and Asymmetric Channel Attention
Abstract
Phantom-less volumetric bone mineral density (vBMD) measurement using computed tomography (CT) presents a cost-effective alternative to conventional phantom-based approaches, yet faces accuracy challenges across varying tube voltages. Current deep learning-based phantom-less solutions frequently overlook the critical role of frequency variance—a crucial factor for precise BMD measurement and cross-voltage generalization. We present a lightweight CT-based phantom-free vBMD measurement framework that addresses critical limitations in cross-voltage generalization. Core innovations include: (1) Frequency-balancing feature modulation with multi-band fusion, preserving spectral measurement cues; (2) A dual-branch architecture combining domain-specific convolutions with cross-frequency interaction; and (3) Asymmetric channel attention, which allocates attention weights based on frequency characteristics, enabling adaptive emphasis on critical low- and high-frequency components. Comprehensive evaluations across 80, 1