Patient History : 29 year old female LMP : January 11, 2010. Positive home pregnancy test Intense back and pelvic pain for twelve hours prior to presentation.
Exams / Procedures ordered: Pelvic ultrasound February 2010 to evaluate for intrauterine pregnancy versus ectopic pregnancy Status post surgery to remove ectopic pregnancy, CT for increased abdominal pain / pressure.
Ultrasound Findings: Transabdominal ultrasound: No intrauterine gestational sac visualized. Moderate amount of free fluid in the cul-de-sac, homogeneous in nature, possibly consistent with hemorrhage. Uterus normal in size measuring 4.2 cm x 4.3 cm. Right ovary is normal in echotexture, size measuring 2.3 cm x 2 cm x 2.6 cm. Moderate amount of free fluid visualized adjacent to the right kidney. Transvaginal ultrasound: No intrauterine gestational sac visualized. Moderate amount of free fluid in the cul-de-sac. Uterus is normal in echotexture and size measuring 8.1 cm in length. Ovaries are normal in echotexture and size, the left measuring 2.1 cm x 2.8 cm x 3.7 cm and the right measuring 2.2 cm x 2.1 cm x 2.7 cm. Follow-up recommendations: Given patient's history of pregnancy with pain and moderate free fluid in the pelvis, ectopic pregnancy is leading differential consideration. Correlation with beta HCG level and OB/GYN consult is recommended.
Differential diagnosis discussion : Hydrosalpinx, pyosalpinx ruled out by positive pregnancy test.Spontaneous abortion ruled out by positive pregnancy test.Blighted ovum ruled out by lack of intrauterine gestational sac.Endometrioma is ruled out by normal endometrial stripe seen in transvaginal exam.Ovarian neoplasm ruled out by visualization of normal ovaries by transabdominal and transvaginal exams.
Defined as implantation of the fertilized ovum outside of the endometrial lining of the uterus.
95-97% of ectopics are in the fallopian tubes, usually isthmus or ampullary. Also can be found within the ovary, on the peritoneal surface (abdominal pregnancy), and on the broad ligament.
Incidence of ectopic pregnancy is approximately 70,000 in the United states alone.
Can rarely (1/4000-1/8000) have a concomitant intrauterine and extrauterine pregnancy, called a heterotopic pregnancy.
With true ectopic, the endometrial stripe can appear normal, thickened, or contain decidual cysts or pseudogestational sac.
The differential diagnosis of a positive BhCG included a normal intrauterine pregnancy, an abnormal intrauterine pregnancy, and an ectopic pregnancy. Must identify intrauterine pregnancy to confidently exclude ectopic.
Also associated with ectopic pregnancy: Intraperitoneal fluid, which may be complex.
Ectopic pregnancy is the leading cause of maternal death during the first trimester.
The identification of an intrauterine pregnancy eliminates the possibility of ectopic pregnancy except in high risk populations such as assisted reproduction.
The early diagnosis of ectopic pregnancy allows treatment options.
Stable patients in whom ectopic pregnancy is indeterminate can be followed with repeat beta-hCG and transvaginal ultrasound in 2-3 days for confirmation.
Methotrexate, direct KCl injection, or surgery.
Case follow-up: The patient had surgery and returned to the radiology department for post-surgical imaging indicated by increased pelvic pain and pressure. CT findings were that the pelvis, large and small bowel were not dilated or thickened. There was a normal appendix. There was a linear soft tissue density within the subcutaneous tissues of the pelvis, that measures 9.3 cm transverse x 0.8 cm AP. There is surrounding stranding in this region. This is likely post surgical. The bladder, uterus and adnexa are within normal limits. There are no drainable fluid collections at this time. There is a trace amount of free fluid within the pelvis, which was seen on the prior pelvic ultrasound. There are no enlarged lymph nodes by CT criteria. The pelvic vasculature is within normal limits. There is no free air or free fluid.
References: Callen PW, et al. Ultrasonography in Obstetrics and Gynecology, 4th ed. Philadelphia: WB Saunders; 2000:912-927. Fylstra DL. Tubal pregnancy: a review of current diagnosis and treatment. Obstetric Gynecology Survey, 1998. Kurtz, A.B. , Middleton W.D., Hertzberg B.S. Ultrasound, The Requisites. Second Edition 2004 Mosby Pp 367,369, 415-431 Reuter KL, Babagbemi TK, Obstetric and Gynecologic Ultrasound, Second Edition 2007 Mosby Elsevier Pp 69,70, 113, 114, 177, 178, 195, 196, 215, 216 http://education.auntminnie.com/teaching files