By Bret W.A. Negro, MD and Sam Lam, MD, RDMS
Chief Complaint: Abdominal pain with vaginal bleeding
Image 1 -
Clip 1 - Watch on YouTube
Clip 2 - Watch on YouTube
1. What anatomy and pathology are shown in the image and clips above?
2. What are the possible sonographic findings in patients with such conditions?
3. What risk factors should increase suspicion for this pathology?
A previously healthy 24-year-old G2P1 female presented to the emergency department with right-sided abdominal pain, missed menstruation, and vaginal bleeding. On arrival, the patient had a pulse of 100 bpm and blood pressure of 152/87 mmHg. Patient reported that abdominal pain was following a fluctuating course for the past 11 days. The pain became acutely worse on the day of arrival. Physical examination revealed tenderness to palpation throughout the lower abdomen, cervical motion tenderness, and a small amount of blood in the vaginal vault. Bedside urine pregnancy was positive. A bedside ultrasound was performed, which showed evidence of a ruptured ectopic pregnancy within the right adnexa. The obstetrics/gynecology service was emergently consulted, and a confirmation ultrasound was performed at the radiology department.
The patient was taken to the operating room, where a ruptured right fallopian tube with approximately 300cc of hemoperitoneum was found. An emergent unilateral salpingectomy was performed. Pathology revealed a benign fallopian tube with chorionic villi. The patient tolerated the procedure well, and was discharged home two days later.
Role of Obstetrics Ultrasound in the Emergency Department
The primary goal of emergency sonography of the pelvis in patients who present with first trimester vaginal bleeding and/or abdominal pain is to identify an intrauterine pregnancy (IUP), and thereby exclude the diagnosis of ectopic pregnancy. For pregnant patients in whom no IUP is seen, the possibility of extrauterine implantation must be considered.
Transvaginal sonography has been shown in various studies to have a high sensitivity and specificity (74-90.9% and 94-99.9%, respectively) for the detection of ectopic pregnancy.
In our case, identification of this patient’s ectopic pregnancy on bedside ultrasound allowed for early obstetrics/gynecology consultation, thereby expediting initiation of treatment for this potentially life-threatening condition.
Answers to questions
1) The first image portrays a sagittal view of the uterine fundus. Of note is the absence of any evidence of intrauterine pregnancy (no gestational sac containing yolk sac or heart beat). A very small amount of free fluid is seen in the rectouterine pouch (of Douglas). The first video clip portrays the uterine fundus and right adnexa in the transverse plane. The right adnexa is notable for two heterogenous masses containing spherical, hypoechoic inclusions. The inferior mass (at the top of the screen) is the right ovary containing a corpus luteum cyst. The more echogenic superior mass (at the bottom of the screen) contains a fetal pole and yolk sac, thus revealing itself as an ectopic pregnancy. The second video clip demonstrates in greater detail the extrauterine gestational sac with its fetal pole and yolk sac. With closer inspection, fetal cardiac activity may be appreciated.
2) Ultrasound findings of ectopic pregnancy fall into 3 categories:1
a. Definite ectopic pregnancy: gestational sac with yolk sac and/or fetal pole outside the uterus.
b. Highly suspicious for ectopic pregnancy: adnexal mass, tubal ring (gestational sac within the fallopian tube), pseudogestational sac (fluid collection in the endometrium without evidence of IUP), and/or large amount of free fluid in the pelvis and/or morison’s pouch in the setting of no definitive intrauterine pregnancy.
c. Indeterminate scan: similar appearance as non-gravid uterus without free fluid or extrauterine masses.
One study showed that among patients diagnosed with ectopic pregnancy, the most common findings on transvaginal ultrasound besides extrauterine gestational sacs were complex adnexal masses (61%), large amount of echogenic fluid in the rectouterine pouch (21%), and tubal rings (16%).2
3) Those at particularly high risk:3
1. Hsu S, Euerle BD. Ultrasound in pregnancy. Emerg Med Clin North Am. 2012;30(4):849-867.
2. Adhikari S, Blaivas M, Lyon M. Diagnosis and management of ectopic pregnancy using bedside transvaginal ultrasonography in the ED: a 2-year experience. Am J Emerg Med. 2007;25:591-596.
3. Sivalingam VN, Duncan CW, Kirk E, et al. Diagnosis and management of ectopic pregnancy. J Fam Plan Reprod Health Care. 2011;37:231-240.