Autor(es)

Costa, Paulo R. ; Pimenta, Elsa B. ; Oostveen, Luuk J. ; Boiset, Gisell R. ; Moura, Raissa A. S. ; Sechopoulos, Ioannis

• Tipo de documento: Artigo Científico
• Fonte: MEDICAL IMAGING 2025: PHYSICS OF MEDICAL IMAGING, PT 1; v. 13405, p. 5-pg., 2025-01-01.

Resumo

Nodule volume doubling time is an important biomarker for lung cancer diagnosis, making accurate estimation of nodule volume in low-dose CT images crucial. Hence, the purpose of this work was to evaluate the precision and accuracy of volume measurements of solid nodules (SN) and ground glass opacities (GGO) in images acquired using conventional energy-integrating (EICT) and CdZnTe photon-counting CT (PCCT) systems, reconstructed using hybrid iterative (HIR) and deep-learning based (DLR) reconstructions. For this, a patient-based anthropomorphic 3D printed lung phantom, five printed SNs of different sizes, and four handmade GGOs were designed, constructed, and validated. To verify the real volumes (i.e., ground truth) of the nodules, ultra-high-resolution images were acquired using a mu CT system. CT images of the phantom were acquired with a CTDIvol of 1.4 mGy. Ten acquisitions were performed per scanner/protocol combination with phantom repositioning to mimic clinical positioning variations. EICT images were reconstructed in normal resolution using HIR. The PCCT images were reconstructed in both normal and high resolution (HR) with HIR and DLR. The relative error (RE) and the coefficient of variation (CV) were used to evaluate the accuracy and precision of the volume estimates, respectively. The choice of reconstruction method and kernel combination is critical in both systems, affecting both precision and accuracy. When comparing EICT and PCCT systems using the combination DLR/Lung kernel, PCCT demonstrates better accuracy (RE < 14% for SN and < 8.1% for GGO) and precision (CV < 5% for SN). (AU)

• Processo FAPESP: 23/03945-8 - Desenvolvimento, validação e aplicação de técnicas para avaliação de protocolos tomográficos de baixas doses
• Beneficiário: Paulo Roberto Costa
• Modalidade de apoio: Bolsas no Exterior - Pesquisa
• Processo FAPESP: 18/05982-0 - P&D&I em metrologia das radiações na área da saúde
• Beneficiário: Linda Viola Ehlin Caldas
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 21/14688-0 - Desenvolvimento de sistemas e procedimentos para dosimetria de pacientes e monitoração de trabalhadores visando a otimização e a melhoria da qualidade das práticas médicas
• Beneficiário: Gisell Ruiz Boiset
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 22/11457-0 - Aplicação de técnicas de manufatura aditiva para produção de objetos simuladores para tomografia computadorizada
• Beneficiário: Paulo Roberto Costa
• Modalidade de apoio: Auxílio à Pesquisa - Regular