Photon-Counting Detector CT for Lenticulostriate Arteries: Comparison with Energy-Integrating Detector CT and Reconstruction Mode Optimization

BACKGROUND AND PURPOSE: Lenticulostriate arteries (LSAs) are micro but clinically critical perforating vessels that remain difficult to visualize using conventional techniques. This study aimed to conduct a preliminary comparison of the visualization of LSAs in head and neck CTA with photon-counting detector CT (PCD-CT) with 4 reconstruction modes. MATERIALS AND METHODS: This retrospective study included patients who underwent head and neck CTA with PCD-CT between January 2024 and May 2024 and those who underwent CTA with energy-integrating detector CT (EID-CT) between September 2023 and May 2024. The images were reconstructed in 4 modes for the PCD-CT group and 1 mode for the EID-CT group. The image quality was evaluated, and the LSAs were visualized by using subjective evaluations and quantitative assessments. The Friedman test was used to compare the characteristics of the 4 reconstruction modes. RESULTS: The PCD-CT group comprised 56 patients (average age 65 ± 14 years; 28 men), and the EID-CT group comprised 28 patients (average age, 64 ± 12 years; 14 men). In the PCD-CT group, the 0.2-mm slice-thickness threshold 3D mode displayed the highest counts of LSAs (right side: 4.00 [range, 3.00-4.00]; left side: 4.00 [range, 3.00-4.00]) and the longest LSAs (right side: 23.33 ± 4.86 mm; left side: 24.18 ± 4.51 mm). The 0.4-mm slice-thickness vascular spectral postprocessing mode obtained higher subjective evaluation scores. Furthermore, the PCD-CT group exhibited a higher count of LSAs, longer LSA lengths, and superior image quality than the EID-CT group. CONCLUSIONS: PCD-CT achieves better visualization of LSAs and image quality than EID-CT and therefore constitutes an important method for observing LSAs in the future.