| Patient Education |
|
Click here for patient education.
|
|
You are in: eMedicine Specialties >
Emergency Medicine > OBSTETRICS AND GYNECOLOGY
Ultrasonography, Pelvic
Article Last Updated: Jun 8, 2006
AUTHOR AND EDITOR INFORMATION
Section 1 of 9  
Author: Verena T Valley, MD, Associate Professor, Director of Ultrasound, Department of Emergency Medicine, University of Mississippi School of Medicine
Verena T Valley is a member of the following medical societies: American College of Emergency Physicians
Coauthor(s):
Christopher A Fly, MD, Assistant Professor, Department of Emergency Medicine, Medical College of Georgia
Editors: Michael S Beeson, MD, MBA, FACEP, Professor of Emergency Medicine, Northeastern Ohio Universities College of Medicine; Program Director, Emergency Medicine Residency, Summa Health System; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Mark Zwanger, MD, MBA, Assistant Professor, Department of Emergency Medicine, Thomas Jefferson University; John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center; Pamela L Dyne, MD, Associate Professor, Program Director, Department of Medicine, Division of Emergency Medicine, University of California at Los Angeles School of Medicine
Author and Editor Disclosure
Synonyms and related keywords:
endovaginal sonography, transabdominal sonography, echography, echo, pelvic sonography, endovaginal imaging, evaluation of bleeding in pregnancy, evaluation of pelvic pain, evaluation of pelvic mass, evaluation of pelvic infection, evaluation of abnormal uterine bleeding, evaluation of pelvic trauma
Background
Pelvic sonography may be viewed as a form or extension of the physical examination. In transabdominal scanning, a full bladder is used to displace bowel gas and serve as an acoustic window to allow a large viewing field of the pelvis. Endovaginal imaging is the preferred technique for emergency physicians because a full bladder is not necessary. Filling the bladder delays the examination.
History
Clinical indications for pelvic sonography include the following:
- Evaluation of vaginal bleeding in early pregnancy
- This indication is well outlined in Pregnancy, Ectopic.
- Subchorionic hemorrhage (implantation bleeding) is a common cause of spotting.
- Endovaginal scanning uses a high-frequency transducer and enables optimal imaging of organs close to the probe, including the endometrium, myometrium, cul-de-sac, and ovaries, which can be seen in detail.
- Evaluation of pelvic pain
- Ultrasonography can be used to evaluate pelvic pain, a common complaint of patients presenting to the ED, and entities such as ovarian cysts, tubo-ovarian abscesses, uterine fibroids, or even an infected pelvic kidney.
- In a female patient who is obese, pelvic ultrasonography can simplify a difficult physical examination.
- Evaluation of a pelvic mass
- Pelvic ultrasonography can be used to determine the etiology of a pelvic mass.
- Compared with endovaginal ultrasonography, transabdominal ultrasonography uses a lower frequency and can penetrate farther, with a large field of view. Thus, fibroids, ovaries, or cysts located high in the pelvis may be out of the focal range of an endovaginal probe. In addition, pelvic kidneys can be visualized.
- Evaluation of pelvic infection
- Tubo-ovarian abscesses are difficult to diagnose at physical examination.
- A normal fallopian tube may not be visualized at endovaginal ultrasonography; however, a fluid- or pus-filled tube can be identified.
- Pelvic inflammatory disease can be identified at ultrasonography.
- Localization of an intrauterine device or foreign body
- Ultrasonography can aid in the localization or detection of an intrauterine device or foreign body.
- An intrauterine device produces a characteristic acoustic artifact (shadow), which is helpful to the physician sonographer.
- Evaluation of trauma
- Views of the pelvis are used at ultrasonographic examination to evaluate for free fluid or clotted blood, which can be present in the pouch of Douglas (cul-de-sac).
- Views of the pelvis obtained before insertion of a Foley catheter are helpful.
- Evaluation of abnormal uterine bleeding in the premenopausal patient as well as the postpartum and postabortion patient
Imaging Studies
- Transabdominal imaging uses a low frequency and is performed to view large fibroids and ovaries that are high in the pelvis and to determine the shape and size of the bladder, uterus, vagina, and cervix.
- A full bladder provides a sonographic window for evaluation of the uterus and adnexa. A full bladder has a teardrop-shaped appearance on the longitudinal view and is rectangular on the transverse view.
- The uterus (longitudinal orientation) is oval and more echogenic than the bladder. The endometrial stripe is an echogenic (bright) line in the central uterus.
- The vagina is a hypoechoic tubular structure posterior to the bladder and caudal to the uterus. A vaginal stripe can be identified.
- The cervix is seen on the transabdominal view.
- The cul-de-sac is important, especially in the evaluation of patients at risk for ectopic pregnancy. A small amount of fluid can be seen in the middle of the menstrual cycle. Otherwise, the cul-de-sac is considered a potential space.
- Ovaries may not be clearly identified on transabdominal images. Ovaries have a characteristic follicular appearance and may be in a variety of positions.
- Endovaginal scanning uses a high-frequency transducer and provides high-quality images of the endometrium, myometrium, cul-de-sac, and ovaries.
- The uterus usually is identified easily on endovaginal sonograms. In the normal position (longitudinal view), the fundus is located on the left side of the imaging screen, with the cervix on the right. The entire uterus may not be seen at one time or on one particular endovaginal view. The uterus is pear shaped on the longitudinal view and round on the transverse view.
- The endometrial stripe is located within the central uterus; its thickness varies with the patient's menstrual cycle. The stripe is thin and less echogenic after menses but becomes thick and echogenic from ovulation to the secretory phase.
- The ovaries usually are located posterior and lateral to the uterus and anterior to the internal iliac artery and vein. They usually are medial to the external iliac vessels. The iliac vessels provide an anatomic landmark for localization of the ovaries. The ovaries are not always identified on endovaginal sonograms. The typical follicular appearance of the ovaries aids in their identification; however, the follicles can be confused with vessels. Using the nonscanning hand, the ultrasonographer can place gentle pressure over the lower abdomen and this may help in moving the ovary into the ultrasound image.
- Endovaginal color flow Doppler ultrasonography
- Some ultrasound machines have endovaginal probes that are capable of color flow imaging. This feature usually is seen on more expensive machines. This capability is helpful in localizing vessels within the pelvis and in determining blood flow to the ovaries, as in ovarian torsion.
- Use of color flow imaging in ectopic pregnancy has been documented.
- When a large tumor or mass (nonfibroid) is found at pelvic ultrasonography, a CT scan may provide valuable information.
Consultations
If abnormalities are noted at pelvic ultrasonography, an obstetrician and gynecologist or radiologist can be consulted for further evaluation. Color flow Doppler imaging may be helpful in certain cases (eg, ovarian torsion), and a repeat ultrasonographic examination may be necessary.
Further Outpatient Care
- Perform further outpatient evaluation and repeat pelvic ultrasonography in cases of ovarian cysts.
Patient Education
- Inform patients that the ultrasonographic examination performed by the emergency physician is for screening of potential life-threatening situations and/or difficult diagnoses.
- If an abnormal ultrasonographic finding is noted, subsequent ultrasonographic examination may be needed for detailed diagnosis.
Medical/Legal Pitfalls
- The biggest pitfall of using ultrasonography in the ED is missing a diagnosis of an ectopic pregnancy. An interstitial pregnancy can be confused with an intrauterine pregnancy.
- Diagnosis of a carcinoma is beyond the present scope of practice for the emergency sonographer. It is sufficient to say that a complex mass is present in a particular anatomical location.
| Media file 1:
Ultrasonography, pelvic. Transabdominal longitudinal view of the female pelvis. |
 |  View Full Size Image | |
Media type: Image
|
| Media file 2:
Ultrasonography, pelvic. Transabdominal transverse view of the female pelvis: The bladder is rectangular. The ovaries are seen bilaterally in the adnexa. |
 | View Full Size Image | |
Media type: Image
|
| Media file 3:
Ultrasonography, pelvic. Endovaginal longitudinal view of the uterus: The endometrial stripe (st) is thickened. The arcuate vessels (arc) can be seen within the uterus and should not be confused with free fluid in the cul-de-sac. |
 | View Full Size Image | |
Media type: Image
|
| Media file 4:
Ultrasonography, pelvic. Endovaginal view of the ovary: Note its location adjacent to an iliac vessel. |
 | View Full Size Image | |
Media type: Image
|
- Bau A, Atri M. Acute female pelvic pain: ultrasound evaluation. Semin Ultrasound CT MR. Feb 2000;21(1):78-93. [Medline].
- Brown DL. Pelvic ultrasound in the postabortion and postpartum patient. Ultrasound Q. Mar 2005;21(1):27-37. [Medline].
- Choi H, Blaivas M, Lambert MJ. Gestational outcome in patients with first-trimester pregnancy complications and ultrasound-confirmed live intrauterine pregnancy. Acad Emerg Med. Feb 2000;7(2):200-3. [Medline].
- Dart RG. Role of pelvic ultrasonography in evaluation of symptomatic first-trimester pregnancy. Ann Emerg Med. Mar 1999;33(3):310-20. [Medline].
- Deutchman M. Pelvic applications. In: Ultrasound in Emergency Medicine. 1995: 11.
- Dodson MG. Clinical uses. In: Transvaginal Ultrasound. Portland, Ore: Book News;1991: 1-18, 165-200.
- Garel L, Dubois J, Grignon A. US of the pediatric female pelvis: a clinical perspective. Radiographics. Nov-Dec 2001;21(6):1393-407. [Medline].
- Ignacio EA, Hill MC. Ultrasound of the acute female pelvis. Ultrasound Q. Jun 2003;19(2):86-98; quiz 108-10. [Medline].
- Lambert MJ, Villa M. Gynecologic ultrasound in emergency medicine. Emerg Med Clin North Am. Aug 2004;22(3):683-96. [Medline].
- Morgan A. Adnexal mass evaluation in the emergency department. Emerg Med Clin North Am. Aug 2001;19(3):799-816. [Medline].
- Okaro E, Valentin L. The role of ultrasound in the management of women with acute and chronic pelvic pain. Best Pract Res Clin Obstet Gynaecol. Feb 2004;18(1):105-23. [Medline].
- Phelan MB, Valley VT, Mateer JR. Pelvic ultrasonography. Emerg Med Clin North Am. Nov 1997;15(4):789-824. [Medline].
- Quillin SP, Siegel MJ. Transabdominal color Doppler ultrasonography of the painful adolescent ovary. J Ultrasound Med. Jul 1994;13(7):549-55. [Medline].
- Stark JE, Siegel MJ. Ovarian torsion in prepubertal and pubertal girls: sonographic findings. AJR Am J Roentgenol. Dec 1994;163(6):1479-82. [Medline].
- Teisala K, Heinonen PK, Punnonen R. Transvaginal ultrasound in the diagnosis and treatment of tubo-ovarian abscess. Br J Obstet Gynaecol. Feb 1990;97(2):178-80. [Medline].
- Timor-Tritsch. The fallopian tubes. In: Transvaginal Sonography. 2nd ed. Lippincott Williams & Wilkins;1991: 131-4.
- Villalba ML, Huynh B, So M. An ovary with a twist: a case of interesting sonographic findings of ovarian torsion. J Emerg Med. Nov 2005;29(4):443-6. [Medline].
- Williams PL, Laifer-Narin SL, Ragavendra N. US of abnormal uterine bleeding. Radiographics. May-Jun 2003;23(3):703-18. [Medline].
Ultrasonography, Pelvic excerpt Article Last Updated: Jun 8, 2006
|
