Farnsworth Paul J, Campeau Norbert G, Diehn Felix E, Yu Lifeng, Leng Shuai, Zhou Zhongxing, Fletcher Joel G, McCollough Cynthia H
Department of Radiology, Mayo Clinic, Rochester, MN, USA.
Interv Neuroradiol. 2023 Jul 3:15910199231175198. doi: 10.1177/15910199231175198.
Recent introduction of photon counting detector (PCD) computed tomography (CT) scanners into clinical practice further improve CT angiography (CTA) depiction of orbital arterial vasculature compared to conventional energy integrating detector (EID) CT scanners. PCD-CTA of the orbit can provide a detailed arterial roadmap of the orbit which can de diagnostic on its own or serve as a helpful planning adjunct for both diagnostic and therapeutic catheter-based angiography of the orbit.
For this review, EID and PCD-CT imaging was obtained in 28 volunteers. The volume CT dose index was closely matched. A dual-energy scanning protocol was used on EID-CT. An ultra-high-resolution (UHR) scan mode was used on PCD-CT. Images were reconstructed at 0.6 mm slice thickness using a closely matched medium-sharp standard resolution (SR) kernel. High-resolution (HR) images with the sharpest quantitative kernel were also reconstructed on PCD-CT at the thinnest slice thickness of 0.2 mm. A denoising algorithm was applied to the HR image series.
The imaging description of the orbital vascular anatomy presented in this work was derived from these patients' PCD-CTA images in combination with review of the literature. We found that orbital arterial anatomy is much better depicted with PCD-CTA, and this work can serve primarily as an imaging atlas of the normal orbital vascular anatomy.
With recent advances in technology, arterial anatomy of the orbit is much better depicted with PCD-CTA as opposed to EID-CTA. Current orbital PCD-CTA technology approaches the necessary resolution threshold for reliable evaluation of central retinal artery occlusion.
与传统能量积分探测器（EID）CT扫描仪相比，光子计数探测器（PCD）CT扫描仪近期引入临床实践进一步改善了眼眶动脉血管系统的CT血管造影（CTA）显示。眼眶PCD-CTA能够提供详细的眼眶动脉路线图，其本身即可用于诊断，或作为眼眶诊断性和治疗性导管血管造影的辅助规划工具。
在本综述中，对28名志愿者进行了EID和PCD-CT成像。容积CT剂量指数紧密匹配。EID-CT采用双能量扫描方案。PCD-CT采用超高分辨率（UHR）扫描模式。使用紧密匹配的中等锐利度标准分辨率（SR）内核以0.6 mm层厚重建图像。PCD-CT还以最薄的0.2 mm层厚重建具有最锐利定量内核的高分辨率（HR）图像。对HR图像序列应用去噪算法。
本研究中呈现的眼眶血管解剖成像描述源自这些患者的PCD-CTA图像并结合文献回顾。我们发现PCD-CTA能更好地显示眼眶动脉解剖，这项研究主要可作为正常眼眶血管解剖的成像图谱。
随着技术的最新进展，与EID-CTA相比，PCD-CTA能更好地显示眼眶动脉解剖。当前的眼眶PCD-CTA技术接近可靠评估视网膜中央动脉阻塞所需的分辨率阈值。
