Fetal Medicine Unit, St George's Hospital, London, UK.
Ultrasound Obstet Gynecol. 2010 Apr;35(4):398-404. doi: 10.1002/uog.7555.
Scimitar syndrome and pulmonary sequestration (PS) have overlapping features. This accounts for postnatal descriptions of a 'sequestrated lung' in scimitar-syndrome patients. We review the similarities and differences in these two conditions, and the antenatal ultrasound findings that allow correct prenatal identification and differential diagnosis.
This was a retrospective analysis of prenatally diagnosed cases of scimitar syndrome or PS that underwent fetal echocardiography between January 1995 and November 2004.
There were five cases of PS and six of scimitar syndrome. Right-sided mediastinal shift (ipsilateral relative to the affected lung) was the commonest indication for referral in scimitar syndrome whereas in sequestration, referral was because of hyperechogenic lung and contralateral mediastinal shift. Lung echogenicity was normal in scimitar syndrome but focally increased in PS. Abnormal, unobstructed pulmonary venous drainage was identified prenatally in four cases of scimitar syndrome. It was normal in three fetuses with sequestration but abnormal and obstructed in the other two cases complicated by hydrothorax. Abnormal systemic arterial supply to the affected lung was easily demonstrated in all fetuses with PS, but could not be shown prenatally in scimitar-syndrome fetuses. Postnatal embolization was warranted in one case with PS and four with scimitar syndrome, one each in the neonatal period.
Prenatally, scimitar syndrome and PS are clearly distinct entities based on lung echogenicity and laterality of mediastinal shift. Hyperechogenic lung and dextrocardia indicate the possibility of PS and scimitar syndrome, respectively. Complete delineation of the vascular pattern should be attempted in all, but is more challenging in scimitar syndrome. Obstructed venous return in PS may identify fetuses at risk of developing hydrothorax.
弯刀综合征和肺隔离症（PS）具有重叠的特征。这就解释了在弯刀综合征患者中有“隔离肺”的描述。我们回顾了这两种情况的相似之处和不同之处，以及可以进行正确产前诊断和鉴别诊断的产前超声发现。
这是对 1995 年 1 月至 2004 年 11 月期间接受胎儿超声心动图检查的产前诊断为弯刀综合征或 PS 的病例进行的回顾性分析。
PS 有 5 例，弯刀综合征有 6 例。右纵隔移位（相对于病变肺同侧）是弯刀综合征最常见的转诊指征，而在隔离症中，转诊是因为肺回声增强和对侧纵隔移位。在弯刀综合征中，肺回声正常，但在 PS 中局部增强。在 4 例弯刀综合征病例中，产前发现异常、无阻塞的肺静脉引流。在 3 例 PS 胎儿中，该引流正常，但在另外 2 例伴有胸腔积液的病例中，该引流异常且阻塞。在所有 PS 胎儿中，异常的体循环动脉供应到病变肺很容易显示，但在弯刀综合征胎儿中不能显示。在 1 例 PS 和 4 例弯刀综合征病例中需要进行产后栓塞，其中 1 例在新生儿期。
从肺回声和纵隔移位的侧位来看，产前的弯刀综合征和 PS 显然是两种不同的实体。回声增强的肺和右位心分别提示 PS 和弯刀综合征的可能性。所有病例均应尝试全面描绘血管模式，但在弯刀综合征中更具挑战性。PS 中静脉回流受阻可能会识别出有发生胸腔积液风险的胎儿。
