Imaging and Clinical Presentation of Caesarean Scar Pregnancy
KH Lee, G Ho, WM Wong, HL Lam, PW Lam
Hong Kong J Radiol 2019;22:123-9
https://doi.org/10.12809/hkjr1916866
Objective: To evaluate transabdominal and transvaginal ultrasound for diagnosing Caesarean scar pregnancy.
Methods: This is a retrospective study of patients diagnosed with Caesarean scar pregnancy in a tertiary referral centre from March 2010 to February 2015. Patient demographics were retrieved from the hospital electronic patient record system. Transabdominal and transvaginal ultrasound scans at the first visit to our centre were reviewed by two radiologists by consensus for the presence of five sonographic signs including empty uterine cavity, empty endocervical canal, gestational sac embedded in low uterine segment/hysterotomy scar, thin/absent myometrium between the gestational sac and bladder, and angular appearance of gestational sac. The sensitivity of each sign was compared using McNemar’s test.
Results: Fifteen patients (mean age 34.5 [28-40] years, mean gestational age 8 weeks 1 day [4 weeks 5 days to 15 weeks 0 days] were included in the analysis. The majority of patients had only one previous Caesarean section (73%). The most common presenting compliant was vaginal bleeding (87%). The ratio between viable and non-viable scar pregnancy was 2:1. Transabdominal ultrasound was inferior to transvaginal ultrasound at detection of thin/absent myometrium (20% vs. 87%, p = 0.002) as well as angular appearance of gestational sac (33.3% vs. 67%, p = 0.031). Subgroup analysis showed that transabdominal ultrasound was reliable for prediction of thin/absent myometrium in the late first or early second trimester.
Conclusions: Caesarean scar pregnancy is a potentially life-threatening condition and accurate diagnosis requires a high index of suspicion. Transabdominal ultrasound is a useful adjunct to transvaginal ultrasound in the diagnosis of Caesarean scar pregnancy.
Author affiliation(s):
KH Lee, G Ho, WM Wong, HL Lam, PW Lam: Department of Radiology, Queen Mary Hospital, Pokfulam, Hong Kong
中文摘要
剖腹產疤痕妊娠的影像學和臨床表現
李錦浩、何潔明、黃慧美、林海苓、林培榮
目的：評估經腹和經陰道超聲波診斷剖腹產疤痕妊娠。
方法：對2010年3月至2015年2月在三級轉診中心診斷為剖腹產疤痕妊娠的患者進行回顧性研究。從醫院電子病歷系統中檢索患者人口統計學數據。由兩名放射科醫師共同評估首次就診婦女的經腹和經陰道超聲波掃描是否存在以下五個超聲徵象，包括空子宮腔、空宮頸管、嵌於低位子宮切片／子宮切開術疤痕的妊娠囊、妊娠囊和膀胱間的薄弱／缺失子宮肌層，以及妊娠囊角度外觀。使用McNemar檢驗比較每個徵象的敏感度。
結果：共15名患者（平均年齡34.5歲〔介乎28-40歲〕，平均胎齡8週1天〔介乎4週5天至15週0天〕被納入分析。大部分患者（73%）只有一次剖腹產史。最常見徵狀是陰道出血（87%）。存活和非存活的疤痕妊娠比例為2：1。在檢測薄弱／缺失子宮肌層（20%比87%，p = 0.002）和妊娠囊角度外觀（33.3%比67%，p = 0.031）方面，經腹超聲波檢查不如經陰道超聲波檢查。亞組分析顯示經腹超聲波檢查能可靠預測早期或孕中期的子宮肌層薄弱或缺失。
結論：剖腹產疤痕妊娠可能危及生命，需要高度懷疑才可準確診斷。經腹超聲波檢查是經陰道超聲波診斷剖腹產疤痕妊娠的有用輔助手段。