放射性肠损伤的影像诊断与评估

Imaging diagnosis and evaluation of radiation-induced intestinal injury

鉴于放射性肠损伤会降低患者生活质量,甚至影响患者预后,及时诊断和准确评估成为放疗后术前诊断及随访中非常重要的环节。影像学检查在放射性肠损伤的诊断中起到至关重要的作用。CT具有扫描速度快、扫描范围广的优点,但其软组织分辨率限制了其诊断效能。MRI具有软组织分辨率高、多角度、多序列、多参数成像的优势,同时可用于评价原发肿瘤治疗效果,但其扫描范围有限。直肠腔内超声可用于观察直肠壁各层厚度、黏膜下层血流信号及微小溃疡及瘘管形成情况。放射性肠损伤的主要影像表现为肠壁增厚、增强扫描分层强化、瘘管、脓肿形成等。既往有研究证实,部分影像特征与疾病的严重程度及预后具有相关性。但是上述影像特征缺乏特异性,在结合患者放疗病史的同时,仍需与肠道肿瘤、缺血性改变及其他肠道炎性病变相鉴别。

Radiation-induced intestinal injury significantly impacts the quality of life and even prognosis of patients.Timely diagnosis and accurate assessment are crucial in clinical practice.Imaging examinations play a vital role in the diagnosis and evaluation of radiation-induced intestinal injury.CT offers fast scanning speed and wide coverage but has limited soft tissue resolution.On the other hand,MRI offers superior soft tissue resolution,along with the capability for multi-sequence and multi-parameter imaging,and the ability to assess the effect of tumor treatment.However,its scanning range is restricted.Endorectal ultrasound enables observation of rectal wall thickness,submucosal blood flow signals,and the development of micro-ulcers and fistulas.The key imaging features of radiation-induced intestinal injury include intestinal wall thickening,layered enhancement on contrast-enhanced scans,fistula formation,and abscess formation,and so on.Previous studies have established correlations between certain imaging features and the severity as well as prognosis of the disease.Nonetheless,these imaging features lack specificity,and require differentiation from tumors,ischemic changes,and other intestinal inflammatory lesions,considering the patient's radiotherapy history in conjunction with the imaging findings.