- Pictorial Review
- Open Access
Radiological appearances of gynaecological emergencies
© European Society of Radiology 2012
- Received: 5 October 2011
- Accepted: 21 February 2012
- Published: 18 April 2012
The role of various gynaecological imaging modalities is vital in aiding clinicians to diagnose acute gynaecological disease, and can help to direct medical and surgical treatment where appropriate. It is important to interpret the imaging findings in the context of the clinical signs and patient's pregnancy status.
Ultrasound and Doppler are readily available in the emergency department, and demonstrate features of haemorrhagic follicular cysts, ovarian cyst rupture, endometriotic cysts and pyosalpinx. Adnexal torsion may also be identified using ultrasound and Doppler, although the diagnosis cannot be safely excluded based on imaging alone. Computed tomography (CT) is not routinely employed in diagnosing acute gynaecological complications. However due to similar symptoms and signs with gastrointestinal and urinary tract pathologies, it is frequently used as the initial imaging modality and recognition of features of gynaecological complications on CT is important.
Although MRI is not frequently used in the emergency setting, it is an important modality in characterising features that are unclear on ultrasound and CT.
MRI is particularly helpful in identifying the site of origin of large pelvic masses, such as haemorrhagic uterine fibroid degeneration and fibroid prolapse or torsion. In this article, we review the imaging appearances of gynaecological emergencies in non-pregnant patients.
• Ultrasonography is easily accessible and can identify life-threatening gynaecological complications.
• Tomography scanners and computed radiography are not routinely used but are important to recognise key features.
• MRI is used for the characterisation of acute gynaecological complications.
• Recognition of the overlap in symptoms between gastrointestinal and gynaecological conditions is essential.
- Tomography scanners
- X-Ray computed
- Magnetic resonance imaging
- Ovarian cysts
- Dermoid cyst
- Torsion abnormality
- Pelvic inflammatory disease
Acute abdominal pain related to the gynaecological tract is a common presentation in the emergency department. One of the challenges facing clinicians is the wide range of differential diagnoses that must be considered when assessing abdominal pain. Often it can be difficult to distinguish gynaecological from gastrointestinal emergencies. In conjunction with clinical findings, various imaging modalities play an important role in diagnosing the cause of pain. In patients presenting with pain that is thought to originate in the gynaecological tract, ultrasound is usually employed as the first imaging modality as it is highly sensitive, fast and easy to access. CT is seldom used as an initial diagnostic tool in suspected gynaecological emergencies due to the risks associated with irradiating the pelvis. However, it may be difficult to localise the site of origin of the symptoms to the gynaecological tract due to the significant overlap in symptoms and signs with gastrointestinal pathologies, and CT may be selected as the first imaging modality. MRI is not usually used in the acute setting but may be important in characterisation of abnormalities that remain indeterminate following ultrasound or CT.
Functional or simple cysts
Ovarian follicles are frequently identified on ultrasound and CT. Developing follicles are commonly seen as functioning cysts during ultrasound examination, usually grow 2 mm per day until ovulation and measure less than 3 cm in diameter. If ovulation does not occur, a follicular cyst develops and appears as an anechoic cyst with a thin wall and posterior acoustic enhancement (seen as an area of increased echogenicity posterior to the cyst). Functional or simple cysts are usually single, less than 6 cm in diameter and thin walled (<3 mm). Follicular cysts usually reabsorb within a 4- to 8-week period .
The corpus luteum forms after ovulation as granulosa cells become luteinized and blood accumulates in the central cavity. Hence, corpus luteal cysts have a thicker, more echogenic wall with increased vascularity seen as peripheral blood flow on Doppler .
Haemorrhagic ovarian cyst
A haemorrhagic ovarian cyst is suspected if a patient presents with symptoms of acute lower abdominal pain, tenderness and in some cases ascites [2–4]. Blood tests often show normocytic anaemia with only mild elevation of inflammatory markers such as CRP and leucocytes when compared to conditions such as appendicitis. Measurement of βhCG levels is also important in excluding ectopic pregnancy, which can have a similar presentation [5, 6].
On CT the typical appearance of an ovarian haemorrhagic cyst is a mixed attenuation mass with a high attenuation component (45-100 HU) within the adnexa, usually with a well-defined smooth outer wall [9, 10]. Depending on the patients’ symptoms, non-contrast CT may or may not have been acquired and so the presence of high attenuation material within the cyst may be difficult to interpret, as this could represent enhancing soft tissue. However, in some cases, contrast-enhanced CT is useful in delineating the cyst wall and a delayed CT may be useful in demonstrating the pooling of contrast-enhanced blood within the pelvis in cases of cystic rupture .
Magnetic resonance imaging is often used when US or CT is unable to characterise a cystic mass and malignancy cannot be excluded. MRI shows haemorrhagic cystic lesions as bright on T1-weighted and intermediate to low on T2-weighted images. The age of the haemorrhage may be estimated by assessing the signal intensity of the haematoma on MRI [11–13]. For example, acute haematoma can be seen as a hypointense region in the ovary on T1-weighted images. As the haematoma becomes chronic its signal becomes bright on both T1- and T2-weighted images. Low T2 signal intensity may also be seen, particularly when haemosiderin deposition has occurred.
Haemorrhagic cyst rupture
On MRI, haemoperitoneum following haemorrhagic cyst rupture will be seen as variable signal intensity free peritoneal fluid with areas of both low and high signal intensity depending on the extent of blood clot formation. When clots develop, layers of low signal intensity fluid levels are often seen on T2-weighted images mixed with high signal intensity fluid. In the case of haemorrhagic ascites, the signal intensity is higher than urine on T1 and lower on T2. MRI enables the pelvic organs to be easily distinguished from each other when compared to CT and US. This can be advantageous when trying to assess whether the haematoma is intraovarian or extraovarian .
Dermoid cyst rupture
Mature cystic teratoma, also known as dermoid cyst, is the most common neoplasm of the ovary. It is derived from ectodermal differentiation of one or more germ cell layers and hence may contain hair, teeth, fat, thyroid tissue, etc. Most cystic teratomas are asymptomatic but 3% may present as torsion and more rarely as dermoid cyst rupture. Patients present with acute pelvic pain, nausea and/or vomiting [15, 16].
Cystic teratomas may appear cystic with hyperechoic areas or hyperechoic densities on ultrasound with loss of through transmission . CT shows a cystic mass with highly complex irregular solid components and the presence of fat within an adnexal mass is diagnostic .
MRI shows very high signal intensity on T1-weighted images due to the sebaceous component, which is characteristic of dermoid cyst. Fat suppression is used to differentiate fat from other haemorrhagic lesions, such as haemorrhagic cysts and endometriomas , which also appear hyperintense on T1-weighted images but remain high in signal intensity on fat-saturated images. If there is rupture of a cystic teratoma, there may be dispersed globules of fat within the peritoneum and signs of a chemical peritonitis with stranding in the peritoneal fat.
Presentation with a ruptured endometriotic cyst is uncommon but significant as emergency surgery may be required due to severe abdominal pain caused by peritoneal irritation resulting from the flow of the contents of the cyst . Ruptured endometriotic cysts typically are multilocular or bilateral ovarian cysts with a thick wall and have loculated ascites confined to the pelvic cavity with pelvic fat infiltration on CT .
Ultrasound, which is frequently used as the initial imaging investigation, may detect an adnexal mass, often in a relatively midline position. However, between 9% and 26% of adnexal torsions occurs in normal-sized ovaries and have normal appearances on ultrasound [27–29]. The use of Doppler sonography can be used to diagnose adnexal torsion. Doppler does this by detecting the absence of blood flow to the torted ovary. A characteristic “whirlpool sign” may be seen on colour Doppler where a corkscrew appearance of a twisted vascular pedicle is apparent. However, studies have found that although Doppler sonography has a high specificity for diagnosing adnexal torsion, it is not sensitive, missing the diagnosis up to 60% of the time [30, 31]. Arterial blood flow may be seen in adnexal torsion for several reasons, leading to false-negative US. Firstly, torsion may be intermittent. Secondly, only one of the two adnexal arteries (uterine and ovarian) may be torted. Thirdly, venous thrombosis secondary to torsion may lead to ovarian necrosis before arterial thrombosis occurs .
CT and MRI may demonstrate a twisted vascular pedicle and thickened fallopian tube in subacute torsion, and identify an underlying mass. Features of torsion using these modalities include eccentric or concentric wall thickening of the torted adnexal mass, fallopian tube thickening, uterine deviation to the effected side and ascites . There may also be eccentric or diffuse poor contrast enhancement of the internal solid component or thickened wall  (Fig. 4d).
When using MRI to evaluate an indeterminate adnexal lesion following US, it is recommended that sequences include a T1 and fat-suppressed T1-weighted sequence to detect haemorrhage (Fig. 4c), which is a less common feature of adnexal torsion . Contrast-enhanced, fat-suppressed, T1-weighted images can be used to detect absence of vascular supply (Fig. 4d). It should be remembered that haemoperitoneum and haemorrhage with ovarian masses can be demonstrated in other acute emergencies such as a haemorrhagic cysts and rupture. Sagittal MR imaging may be used to detect tubular protrusion from an adnexal mass towards the inferior uterus. This feature can be a cardinal sign of tube thickening. MRI can also detect smooth wall thickening of a twisted ovarian mass in cases of adnexal torsion . Other MRI features that can suggest haemorrhagic infarction due to torsion include a thickened cyst wall and low enhancement in the solid component of the twisted ovarian mass [14, 32]. The ovary may be grossly enlarged due to oedema (Fig. 4b).
Fibroids: acute presentations
Fibroids (leiomyoma) are the most common pelvic tumours affecting females in the fertile age group. They occur in 20-40% of females above 30 years of age. These benign smooth muscle tumours are sensitive to oestrogens, which are thought to be a main contributory factor to fibroid growth over time. Symptoms usually manifest during the 4th decade . As fibroids may cause acute pain, patients may present at the emergency department. Acute pain may be caused by the degeneration of a fibroid when it outgrows its blood supply, torsion of a pedunculated fibroid or prolapse of a submucosal fibroid. Red (or haemorrhagic) degeneration is another type of acute fibroid degeneration seen in pregnancy and in patients on the oral contraceptive pill, caused by thrombosis of the venous outflow and resulting in a rapid increase in the size of the fibroid with acute haemorrhagic infarction. Acute complications of fibroids are rarely seen but may be serious. Acute bleeding into fibroids can lead to hypovolaemic shock and cause the death of the patient [34, 35].
Ultrasound is often the initial diagnostic imaging modality for suspected complications of fibroids. A simple fibroid is usually seen as a hypoechoic lesion that may be well defined and arising within the surrounding myometrium. Fibroids can also demonstrate posterior acoustic enhancement or attenuation without any calcification. Degeneration of fibroids gives a more complex US appearance with areas of cystic change and Doppler can show circumferential vascularity. Fibroids that are torted or are necrotic will show absence of flow on Doppler US.
CT may show a heterogeneously enhancing mass prolapsing into the vagina and perineum. Often the mass can show diffuse low attenuation, which indicates necrosis of the fibroid.
Pelvic inflammatory disease
Pelvic inflammatory disease (PID) is described as a spread of inflammation from the endometrial cavity and fallopian tubes into the pelvis. It is an umbrella term, which encompasses endometritis, salpingitis and tubo-ovarian abscesses. It usually affects women in the reproductive age group and accounts for 25% of visits to the emergency departments with gynaecological pain. The symptoms of pelvic inflammatory disease are general aching pain in the pelvis that varies in severity. It is also common for sufferers to have vaginal discharge and cervical excitation on examination. Patients often have a leukocytosis, increased inflammatory markers and may be febrile. A long course of antibiotic treatment is the most common treatment of PID. Complications of untreated PID can have serious implications for the patient and include infertility, ectopic pregnancy, chronic abdominal pain and the development of tubo-ovarian abscesses requiring surgical intervention. Organisms such as sexually transmitted Chlamydia trachomatas and Nissera gonorrhoea are causative agents in developing ascending cervicitis. Other conditions that may lead to the development of tubo-ovarian abscess are diverticulitis, appendicitis and tuberculosis [37, 40].
US, CT and MRI indications and findings
Simple ovarian cysts
Anechoic 3-6 cm cyst, with thin wall <3 mm and minimal thin septations
Well-defined cystic adnexal mass of low attenuation and smooth well-defined wall
Well-defined cystic adnexal mass of low T1 and high T2 signal intensity and smoothly enhancing wall
Haemorrhagic ovarian cyst
Not indicated unless suspected cyst rupture with severe pain
Not indicated unless a cyst is considered indeterminate on US
Isoechoic to ovarian stoma when acute. Develops fine, reticular “spider-web” or lace-like pattern. Vascular wall with avascular internal clot material. If ruptured, then free pelvic fluid with low-level echos is seen
Hyperdense mass within the adnexa. Smooth enhancing cyst wall. If ruptured, then high-density free fluid is seen in pelvis and there may be contrast pooling in the pelvis on delayed images in cases of rupture
Appearance depends on age of blood. Typically, high T1 material is seen within the cyst. Cyst rupture may demonstrate a combination of low and high T1 and T2 free fluid in pelvis
Not indicated unless suspected acute rupture
Not indicated unless a cyst is considered indeterminate on US
Ovarian cyst containing ground–glass appearance, with homogenous internal echogenicity. May be multiple
Ruptured endometriotic cyst may be associated with loculated dense ascites often confined to the pelvic cavity due to adhesions
Typically T1 hyperintense cysts with T2 shading; frequently bilateral. Chronic fibrotic changes in pouch of Douglas may be seen
Indicated although of low sensitivity
May be undertaken due to acute pain with unclear diagnosis
Not indicated unless the adnexal mass is considered indeterminate
Doppler whirlpool sign with corkscrew appearance of twisted vascular pedicle and an enlarged ovary with peripherally located follicles
Twisted vascular pedicle
Oedema of ovarian stroma. There may be absence of vascular supply and low level enhancement in the solid component of the ovarian mass
Wall thickening of torted adnexal mass. Poor contrast enhancement of internal solid components
May be undertaken if patient has acute pain
Not usually indicated. May be used to differentiate a degenerating fibroid from a complex adnexal mass
Degeneration gives a complex US appearance with areas of cystic change
Degeneration gives cystic hypodense appearance of fibroid mass
Cystic degeneration is seen as complex high T2 signal intensity within a fibroid
Doppler shows circumferential vascularity
Can be difficult to distinguish from a complex ovarian cyst when large
Red degeneration within a fibroid is seen as
Absence of flow if torted
high T1 signal centrally due to blood with low T2 signal at periphery due to haemosiderin deposition
Submucosal pedunculated fibroid may extend into endocervix or vagina from a stalk and may tort
Pelvic inflammatory disease
Not usually indicated but may be done if diagnosis is uncertain
Not indicated unless the diagnosis is uncertain and US is indeterminate
Clinical signs are key to diagnosis. US may be normal. Thickened endometrium or pyosalpinx may be seen
Tubo-ovarian abscesses appear as bilateral thick-walled complex enhancing masses with tubal configuration and surrounding inflammation
Tubo-ovarian abcesses appear as complex thick-walled enhancing adnexal masses with surrounding inflammation
- Stenchever M (2001) Comprehensive gynaecology. 2nd edn. MosbyGoogle Scholar
- Vandermeer FQ, Wong-You-Cheong JJ (2009) Imaging of acute pelvic pain. Clin Obstet Gynecol 52:2–20PubMedView ArticleGoogle Scholar
- Ogawa Y, Fukuda T, Matsunaga N et al (1991) Computed tomographic features in ovarian bleeding. Nihon Igaku Hoshasen Gakkai Zasshi 51:394–399PubMedGoogle Scholar
- Hertzberg BS, Kliewer MA, Bowie JD et al (1999) Adnexal ring sign and hemoperitoneum caused by hemorrhagic ovarian cyst: pitfall in the sonographic diagnosis of ectopic pregnancy. AJR Am J Roentgenol 173:1301–1302PubMedView ArticleGoogle Scholar
- Kaakaji Y, Nghiem HV, Nodell C, Winter TC (2000) Sonography of obstetric and gynecologic emergencies: Part II, Gynecologic emergencies. AJR Am J Roentgenol 174:651–656PubMedView ArticleGoogle Scholar
- Kaakaji Y, Nghiem HV, Nodell C, Winter TC (2000) Sonography of obstetric and gynecologic emergencies: Part I, Obstetric emergencies. AJR Am J Roentgenol 174:641–649PubMedView ArticleGoogle Scholar
- Jeong YY, Outwater EK, Kang HK (2000) Imaging evaluation of ovarian masses. Radiographics 20:1445–1470PubMedView ArticleGoogle Scholar
- Valentin L (2004) Use of morphology to characterize and manage common adnexal masses. Best Pract Res Clin Obstet Gynaecol 18:71–89PubMedView ArticleGoogle Scholar
- Borders RJ, Breiman RS, Yeh BM, Qayyum A, Coakley FV (2004) Computed tomography of corpus luteal cysts. J Comput Assist Tomogr 28:340–342PubMedView ArticleGoogle Scholar
- Bennett GL, Slywotzky CM, Giovanniello G (2002) Gynecologic causes of acute pelvic pain: spectrum of CT findings. Radiographics 22:785–801PubMedView ArticleGoogle Scholar
- Nishino M, Hayakawa K, Iwasaku K, Takasu K (2003) Magnetic resonance imaging findings in gynecologic emergencies. J Comput Assist Tomogr 27:564–570PubMedView ArticleGoogle Scholar
- Kataoka ML, Togashi K, Inoue T, Fujii S, Konishi J (1999) Evaluation of ectopic pregnancy by magnetic resonance imaging. Hum Reprod 14:2644–2650PubMedView ArticleGoogle Scholar
- Busard MP, Pieters-van den Bos IC, Mijatovic V, Van Kuijk C, Bleeker MC, van Waesberghe JH (2011) Evaluation of MR diffusion-weighted imaging in differentiating endometriosis infiltrating the bowel from colorectal carcinoma. Eur J Radiol Sept 9 [Epub ahead of print]Google Scholar
- Webb EM, Green GE, Scoutt LM (2004) Adnexal mass with pelvic pain. Radiol Clin North Am 42(2):329–348PubMedView ArticleGoogle Scholar
- Ding DC, Chen SS (2005) Conservative laparoscopic management of ovarian teratoma torsion in a young woman. J Chin Med Assoc 68:37–39PubMedView ArticleGoogle Scholar
- Kalish GM, Patel MD, Gunn ML, Dubinsky TJ (2007) Computed tomographic and magnetic resonance features of gynecologic abnormalities in women presenting with acute or chronic abdominal pain. Ultrasound Q 23:167–175PubMedView ArticleGoogle Scholar
- Comerci JT, Licciardi F, Bergh PA, Gregori C, Breen JC (1994) Mature cystic teratoma: a clinicopathologic evaluation of 517 cases and review of the literature. Obstet Gynecol 84:22–28PubMedGoogle Scholar
- Outwater EK, Siegelman ES, Hunt JL (2001) Ovarian teratomas: tumor types and imaging characteristics. Radiographics 21:475–490PubMedView ArticleGoogle Scholar
- Bis KG, Vrachliotis TG, Shetty AN, Maximovich A, Hricak H (1997) Pelvic endometriosis: MR imaging spectrum with laparoscopic correlation and diagnostic pitfalls. Radiographics 17:639–655PubMedView ArticleGoogle Scholar
- Porpora MG, Gomel V (1997) The role of laparoscopy in the management of pelvic pain in women of reproductive age. Fertil Steril 68:765–779PubMedView ArticleGoogle Scholar
- Coulier B, Malbecq S, Brinon PE, Ramboux A (2008) MDCT diagnosis of ruptured tubal pregnancy with massive hemoperitoneum. Emerg Radiol 15:179–182PubMedView ArticleGoogle Scholar
- Lee YR (2011) CT imaging findings of ruptured ovarian endometriotic cysts: emphasis on the differential diagnosis with ruptured ovarian functional cysts. Korean J Radiol 12:59–65PubMedPubMed CentralView ArticleGoogle Scholar
- Togashi K, Nishimura K, Kimura I (1991) Endometrial cysts: diagnosis with MR imaging. Radiology 180:73–78PubMedView ArticleGoogle Scholar
- Huchon C, Fauconnier A (2010) Adnexal torsion: a literature review. Eur J Obstet Gynecol Reprod Biol 150:8–12PubMedView ArticleGoogle Scholar
- Haskins T, Shull BL (1986) Adnexal torsion: a mind-twisting diagnosis. South Med J 79:576–577PubMedView ArticleGoogle Scholar
- Hibbard LT (1985) Adnexal torsion. Am J Obstet Gynecol 152:456–461PubMedView ArticleGoogle Scholar
- Bider D, Mashiach S, Dulitzky M, Kokia E, Lipitz S, Ben-Rafael Z (1991) Clinical, surgical and pathologic findings of adnexal torsion in pregnant and nonpregnant women. Surg Gynecol Obstet 173:363–366PubMedGoogle Scholar
- Chang HC, Bhatt S, Dogra VS (2008) Pearls and pitfalls in diagnosis of ovarian torsion. Radiographics 28:1355–1368PubMedView ArticleGoogle Scholar
- Mage G, Canis M, Menhes H, Pouly JL, Bruhat MA (1989) Laparoscopic management of adnexal torsion. A review of 35 cases. J Reprod Med 34:520–524PubMedGoogle Scholar
- Pena JE, Ufberg D, Cooney N, Denis AL (2000) Usefulness of Doppler sonography in the diagnosis of ovarian torsion. Fertil Steril 73:1047–1050PubMedView ArticleGoogle Scholar
- Lee EJ, Kwon HC, Joo HJ, Suh JH, Fleischer AC (1998) Diagnosis of ovarian torsion with color Doppler sonography: depiction of twisted vascular pedicle. J Ultrasound Med 17:83–89PubMedGoogle Scholar
- Rha SE, Byun JY et al (2002) CT and MR imaging features of adnexal torsion. Radiographics 22:283–294PubMedView ArticleGoogle Scholar
- Lee JH, Park SB, Shin SH (2009) Value of intra-adnexal and extra-adnexal computed tomographic imaging features diagnosing torsion of adnexal tumor. J Comput Assist Tomogr 33:872–876PubMedView ArticleGoogle Scholar
- Vercellini P, Maddalena S, de Giorgi O, Aimi G, Crosignani PG (1998) Abdominal myomectomy for infertility: a comprehensive review. Hum Reprod 13:873–879PubMedView ArticleGoogle Scholar
- Neuwirth RS (1995) Hysteroscopic submucous myomectomy. Obstet Gynecol Clin North Am 22:541–558PubMedGoogle Scholar
- Ueda H, Togashi K, Konishi I (1999) Unusual appearances of uterine leiomyomas: MR imaging findings and their histopathologic backgrounds. Radiographics 19 Spec No: S131-145Google Scholar
- Dohke M, Watanabe Y, Okumura A (2000) Comprehensive MR imaging of acute gynecologic diseases. Radiographics 20:1551–1566PubMedView ArticleGoogle Scholar
- Wilde S, Scott-Barrett S (2009) Radiological appearances of uterine fibroids. Indian J Radiol Imaging 19:222–231PubMedView ArticleGoogle Scholar
- Kim JW, Lee CH, Kim KA, Park CM (2008) Spontaneous prolapse of pedunculated uterine submucosal leiomyoma: usefulness of broccoli sign on CT and MR imaging. Clin Imaging 32:233–235PubMedView ArticleGoogle Scholar
- Tukeva TA, Aronen HJ, Karjalainen PT, Molander P, Paavonen T, Paavonen J (1999) MR imaging in pelvic inflammatory disease: comparison with laparoscopy and US. Radiology 210:209–216PubMedView ArticleGoogle Scholar
- Sam JW, Jacobs JE, Birnbaum BA (2002) Spectrum of CT findings in acute pyogenic pelvic inflammatory disease. Radiographics 22:1327–1334PubMedView ArticleGoogle Scholar