常规超声及超声造影鉴别诊断局灶性机化性肺炎与非特异性肺炎的初步研究

目的探讨局灶性机化性肺炎（FOP）的常规超声及超声造影特征，并与局灶性慢性非特异性肺炎进行对比，以期为二者鉴别诊断提供依据。 方法回顾性收集2017年1月至2022年4月于北京大学第三医院确诊并在超声科行常规超声及超声造影检查的胸膜下FOP患者24例（FOP组），选取同期确诊的40例局灶性慢性非特异性肺炎患者（非特异性肺炎组）为对照组。对2组患者的常规超声特征以及造影剂到达病灶时间、造影增强时相、造影增强模式、病变内造影剂增强程度、增强均匀程度、有无未增强区等超声造影特征进行比较分析。 结果常规二维超声图像上FOP组出现空气支气管征的比例（62.5%，15/24）高于非特异性肺炎组（35%，14/40），二者比较差异有统计学意义（P=0.032）。相较于非特异性肺炎组，FOP以均匀增强为主（20/24，83.3%），而非特异性肺炎中55%为不均匀增强（22/40），二者比较差异有统计学意义（P=0.003）。FOP组仅2例（2/24，8.3%）出现造影无灌注区，与非特异性肺炎组（15/40，37.5%）比较，差异有统计学意义（P=0.011）。 结论FOP更常见空气支气管征，超声造影常表现为动脉期均匀增强、较少出现灌注缺损区。这些特征有助于FOP与慢性非特异性肺炎的鉴别诊断。

Differential diagnosis of focal organizing pneumonia and subpleural focal chronic nonspecific inflammation by conventional ultrasound and contrast-enhanced ultrasound: a preliminary study

ObjectiveTo compare the gray-scale and contrast-enhanced ultrasound features between focal organizing pneumonia (FOP) and subpleural focal chronic nonspecific inflammation. MethodsTwenty-four patients with FOP and 40 patients with focal chronic nonspecific inflammation pathologically diagnosed at Peking University Third Hospital from January 2017 to April 2022 were analyzed retrospectively. The conventional ultrasonic features of the two groups, as well as the arrival time of contrast agent, the phase of enhancement, the enhance mode, the degree of enhancement, the degree of uniformity of enhancement, and the presence or absence of non-enhanced areas were compared between the two groups. ResultsOn ultrasound images, the proportion of patients with air bronchogram sign (62.5%, 15/24) was significantly higher in the FOP group than in the focal chronic nonspecific inflammation group (14/40, 35%, P=0.032). The results of contrast-enhanced ultrasound showed that the two groups were supplied by the pulmonary artery. Compared with the focal chronic nonspecific inflammation group, FOP was mainly uniformly enhanced (20/24, 83.3%), while 55% of cases in the focal chronic nonspecific inflammation group was unevenly enhanced (22/40, 55.0%); the difference between the two groups was statistically different (P=0.003). Non-enhanced areas within the lesions were more common in the chronic nonspecific inflammation group (15/40, 37.5% vs 2/24, 8.3%, P=0.011). ConclusionFOP is more common with air bronchogram sign. Contrast-enhanced ultrasound shows homogeneous and diffuse enhancement, and few perfusion defects. These features may be helpful to the differential diagnosis of FOP and focal chronic nonspecific inflammation.