放射性核素肺显像诊断肺栓塞研究进展

PE是常见的危及患者生命的急重症,早期准确诊断至关重要.放射性核素肺显像是诊断PE的无创影像学方法.近年来,肺V/Q显像取得了重要研究进展.(1)20世纪90年代初由肺栓塞诊断前瞻性研究(PIOPED)制定了目前广泛应用的V/Q显像PIOPED Ⅰ诊断标准.在该研究中,PE中度可能性和低度可能性患者(即非诊断性结果)的比例很高.因此,PIOPED Ⅰ标准存在缺陷,众多学者对此进行了研究,并制定了多个新的诊断标准,如PIOPEDⅡ、PISAPED和EANM标准;(2) SPECT V/Q显像为三维成像,具有空间分辨率高和受组织重叠影响少的优势,能发现亚段水平和肺底部位的病灶,其诊断准确性高于V/Q平面显像和多层螺旋CT;(3)近年出现的SPECT/CT一次检查可同时获取SPECT图像和CT图像,两者融合可同时提供功能信息和解剖信息,优势互补,提高了PE诊断的准确性.

Advances of ventilation/perfusion scintigraphy in diagnosing acute pulmonary embolism

PE is a severe and potentially fatal disease. Early and accurate diagnosis of PE is cruci- al. Lung seintigraphy is a non-invasive imaging technique to diagnose PE. Recently, major researeh advances have been achieved in V/Q scintigraphy. The prospective investigation of PE diagnosis （PIOPED） I criteria was formalized in the 1990s. In the PIOPED study, the majority of patients had either intermediate probabihty results or low probability results. Accordingly, the PIOPED I criteria were fundamentally flawed. Many investigators established new criteria, such as HOPED ]] , prospective investigative study of acute pulmonary embolism diagnosis （PISAPED） and European Association of Nuclear Medicine（EANM）. With the use of SPECT acquisition, the V/Q scan has undergone a transition to three-dimensional volumetric ima- ging. SPECT has a higher spatial resolution than planar V/Q scintigraphy, so it can detect abnormalities particularly at the subsegmental level and in the lung bases, where the segments are tightly packed. SPECT V/Q has proven to be clearly superior to planar V/Q and multi-detector CT （MDCT）. When SPECT and CT images are acquired on the same scanning bed in the same imaging session, great registration accuracy is achieved with such SPECT/CT scanners. For lung imaging, the emergence of SPECT/CT scanners gives reporting specialists two options to combine structural and functional data and potentially to improve the overall diagnostic accuracy of the modality.