股前外侧穿支皮瓣术前CT血管成像扫描及重建方案研究

Study on Preoperative CT Angiography Scanning and Reconstruction Plan for Anterolateral Thigh Perforator Flap

目的:股前外侧皮瓣是一种用于头颈部缺损重建的多功能骨干皮瓣,其穿支血管的位置、走向和来源评估对制定合理的手术计划中至关重要。小视野(Small FOV)技术可以缩小重建视野,增加图像分辨率,提升对穿支血管显示的空间分辨率;双阶段造影剂注射法增强末梢血管的充盈压力;多平面重建(MPR)对感兴趣区域进行冠状位重组,观察旋股外动脉远端各皮支血管分布;曲面重建(CPR)生成穿支血管的曲面图像,将穿支血管曲面路径与旋股外动脉主干容积成像图像融合,确定穿支血管的位置及其走行。本研究旨在通过各种计算机断层血管造影(CTA)扫描和后处理技术提高皮瓣穿支血管的可视化。方法:研究组为我院耳鼻喉头颈外科于2018年1月至2021年8月对13例头颈部肿瘤术后缺损患者行皮瓣术前CTA改进扫描方案。对照组选取首都医科大学附属北京友谊医院放射科2020年9月至2023年4月,为进行双下肢动脉CT非能谱血管成像检查的13例患者,股动脉及其分支血管无明显病变。对两组血管成像质量进行主观评价,并对旋股外动脉的对比噪声比(CNR)和信噪比(SNR)进行客观评价。结果:研究组SNR较对照组稍高,但两组差别无统计学意义。研究组CNR均值为18.25±7.38,对照组CNR均值为7.26±2.64,研究组CNR明显高于对照组,两组差别有统计学意义。研究组与对照组图像质量主观评价无差异。研究组术前在CTA上检测到的穿支血管100%在手术中得到证实。结论:多种技术综合应用增加皮支血管与周围组织的对比,获得满意的CT图像质量,提高图像分析的准确性,给临床医生分析供血血管的位置、走行和来源提供了更好的技术支持。

Objective:The anterolateral thigh(ALT)flap is a multifunctional diaphyseal flap used to reconstruct head and neck defects.The location,destination,and source of the perforator vessels are crucial for developing a reasonable surgical plan.The small FOV technique can narrow the reconstruction field,increase image resolution,and enhance the spatial resolution of perforator vessels.The two-stage contrast injection method enhances peripheral vessel filling pressure.Multiplanar reformation(MPR)allows coronal reconstruction of the area of interest permitting observation of the distribution of the distal perforator vessels of the lateral circumflex femoral artery.Curved multiplanar reformation(CPR)generates a curved image of the perforator vessels by integrating the curved path of the perforator vessels with the volume-rendering image of the lateral circumflex femoral artery to determine the location and course of the perforator vessels.This study was performed to improve perforator flap vessel visualization using various computed tomography angiography(CTA)scanning and post-processing techniques.Methods:The study group consisted of 13 patients with head and neck tumor defects who underwent improved preoperative CTA scanning between January 2018 and August 2021 at our hospital’s Department of Otorhinolaryngology,Head and Neck Surgery.The control group included 13 patients with no significant lesions in the femoral artery or its branches who underwent non-spectral CT angiography of the bilateral lower extremity arteries between September 2020 and April 2023 at the Radiology Department of Beijing Friendship Hospital,Capital Medical University.Vascular imaging quality was subjectively scored,and the contrast-to-noise ratios(CNR)and signal-to-noise ratios(SNR)of the lateral circumflex femoral artery were objectively evaluated.Results:While SNR in the intervention group was slightly higher than that in the control group,no significant difference was observed between the two groups.The average CNR in the study group was 18.25±7.38,while that in the control group was 7.26±2.64.The CNR in the study group was significantly higher than that in the control group,with a statistically significant difference between the two groups.No significant difference in subjective image quality scores was observed between the study and control groups.All perforator vessels detected on preoperative CTA in the study group were confirmed intraoperatively.Conclusions:Comprehensive application of multiple techniques increased the contrast between the perforator vessels and surrounding tissues,resulting in satisfactory CT image quality.These methods improve the accuracy of image analysis and provide better technical support for clinicians in analyzing the location,course,and source of blood vessels.