- Author: Erik D Schraga, MD; Chief Editor: Eugene C Lin, MD more...
Ovarian torsion (adnexal torsion) is an infrequent but significant cause of acute lower abdominal pain in women. This condition is usually associated with reduced venous return from the ovary as a result of stromal edema, internal hemorrhage, hyperstimulation, or a mass. The ovary and fallopian tube are typically involved.
The clinical presentation is often nonspecific with few distinctive physical findings, commonly resulting in delay in diagnosis and surgical management. A quick and confident diagnosis is required to save the adnexal structures from infarction.
Ovarian torsion involves torsion of the ovarian tissue on its pedicle leading to reduced venous return, stromal edema, internal hemorrhage, and infarction with the subsequent sequelae. Ovarian cysts are 3 times more common in ovarian torsion cohorts than in the general population, and evidence suggests that ovarian cysts are very common in asymptomatic pregnant women but spontaneously resolve as the pregnancy progresses. Pregnancy is a risk factor for torsion (odds ratio: 18:1) but remains an uncommon event (0.167%).
Ovarian torsion classically occurs unilaterally in a pathologically enlarged ovary. The irregularity of the ovary likely creates a fulcrum around which the oviduct revolves. The process can involve the ovary alone but more commonly affects both the ovary and the oviduct (adnexal torsion). Approximately 60% of cases of torsion occur on the right side.
Although torsion may rarely occur in normal adnexa, it more frequently arises from one of many anatomic changes. Torsion of a normal ovary is most common among young children, in whom developmental abnormalities (eg, excessively long fallopian tubes or absent mesosalpinx) may be responsible. In fact, fewer than half of ovarian torsion cases in pediatric patients involve cysts, teratomas, or other masses.
During early pregnancy, the presence of an enlarged corpus luteum cyst likely predisposes the ovary to torsion. Women undergoing induction of ovulation for infertility carry an even greater risk, in that numerous theca lutein cysts significantly expand the ovarian volume.
Anatomic changes affecting the weight and the size of the ovary may alter the position of the fallopian tube and allow twisting to occur.
Pregnancy is associated with, and may be responsible for, torsion in approximately 20% of adnexal torsion cases, probably secondary to the ovarian enlargement that occurs during ovulation in combination with laxity of the supporting tissues of the ovary.
Congenitally malformed and elongated fallopian tubes may be seen, particularly in young, prepubertal patients.
Ovarian tumors, both benign and malignant, are implicated in 50-60% of cases of torsion. Involved masses are nearly all larger than 4-6 cm, although torsion is still possible with smaller masses. Dermoid tumors are most common. Malignant tumors are much less likely to result in torsion than benign tumors are. This is because of the presence of cancerous adhesions that fix the ovary to surrounding tissues.
Conversely, patients with a history of pelvic surgery (principally tubal ligation) are at increased risk for torsion, probably because of adhesions that provide a site around which the ovarian pedicle may twist.
Studies reveal that ovarian torsion is the fifth most common gynecologic surgical emergency, accounting for 2.7% of cases of acute gynecologic complaints in 1 series. Ovarian torsion is encountered more often in women who have had ovarian stimulation, which likely accounts for a slightly increased incidence in developed countries.
Ovarian torsion applies strictly to the female sex. It can occur at any age, but most cases occur in the early reproductive years. The median age reported by a large review was 28 years. The percentage of patients younger than 30 years is approximately 70-75%. Two groups of women show a particular tendency to be affected by adnexal torsion (ovarian torsion): (1) women in their mid 20s and (2) women who are postmenopausal.
Approximately 20% of cases of torsion occur during pregnancy.[2, 3] Postmenopausal women with an adnexal mass may also be affected. Adolescents are also at risk; this may be because of changes in the weight of their maturing adnexa. Approximately 17% of cases have been found to occur in premenarchal or postmenopausal women. Although ovarian torsion in very young children is rare, a case of ovarian cyst torsion was reported in a 2-year-old.
With early diagnosis and appropriate treatment, the prognosis of ovarian torsion is excellent. However, most patients with ovarian torsion have a delayed diagnosis, often resulting in infarction and necrosis of the ovary. The ovarian salvage rate has been reported below 10% in adults but as high as 27% in a study among pediatric patients.
Although the loss of a single ovary is unlikely to result in significantly reduced fertility and no cases of death due to ovarian torsion have been reported, early diagnosis allows conservative laparoscopic treatment and reduction in complications. In a retrospective large study comparing pregnant patients with adnexal torsion to nonpregnant patients with adnexal torsion, the recurrence rate of torsion was 19.5% in pregnant women and 9.1% in nonpregnant women.
Asfour V, Varma R, Menon P. Clinical risk factors for ovarian torsion. J Obstet Gynaecol. 2015. 35 (7):721-5. [Medline].
Bider D, Mashiach S, Dulitzky M, Kokia E, Lipitz S, Ben-Rafael Z. Clinical, surgical and pathologic findings of adnexal torsion in pregnant and nonpregnant women. Surg Gynecol Obstet. 1991 Nov. 173(5):363-6. [Medline].
Griffin D, Shiver SA. Unusual presentation of acute ovarian torsion in an adolescent. Am J Emerg Med. 2008 May. 26(4):520.e1-3. [Medline].
Huang TY, Lau BH, Lin LW, Wang TL, Chong CF, Chen CC. Ovarian cyst torsion in a toddler. Am J Emerg Med. 2009 Jun. 27(5):632.e1-3. [Medline].
Anders JF, Powell EC. Urgency of evaluation and outcome of acute ovarian torsion in pediatric patients. Arch Pediatr Adolesc Med. 2005 Jun. 159(6):532-5. [Medline].
Hasson J, Tsafrir Z, Azem F, Bar-On S, Almog B, Mashiach R, et al. Comparison of adnexal torsion between pregnant and nonpregnant women. Am J Obstet Gynecol. 2010 Jun. 202(6):536.e1-6. [Medline].
Ashwal E, Hiersch L, Krissi H, Eitan R, Less S, Wiznitzer A, et al. Characteristics and Management of Ovarian Torsion in Premenarchal Compared With Postmenarchal Patients. Obstet Gynecol. 2015 Sep. 126 (3):514-20. [Medline].
Ashwal E, Krissi H, Hiersch L, Less S, Eitan R, Peled Y. Presentation, Diagnosis, and Treatment of Ovarian Torsion in Premenarchal Girls. J Pediatr Adolesc Gynecol. 2015 Mar 28. [Medline].
Ganer Herman H, Shalev A, Ginat S, Kerner R, Keidar R, Bar J, et al. Clinical characteristics of adnexal torsion in premenarchal patients. Arch Gynecol Obstet. 2016 Mar. 293 (3):603-8. [Medline].
Koumoutsea EV, Gupta M, Hollingworth A, Gorry A. Ovarian Torsion in the Third Trimester of Pregnancy Leading to Iatrogenic Preterm Delivery. Case Rep Obstet Gynecol. 2016. 2016:8426270. [Medline].
Fleischer AC, Brader KR. Sonographic depiction of ovarian vascularity and flow: current improvements and future applications. J Ultrasound Med. 2001 Mar. 20(3):241-50. [Medline].
Lee EJ, Kwon HC, Joo HJ, Suh JH, Fleischer AC. Diagnosis of ovarian torsion with color Doppler sonography: depiction of twisted vascular pedicle. J Ultrasound Med. 1998 Feb. 17(2):83-9. [Medline].
Koonings PP, Grimes DA. Adnexal torsion in postmenopausal women. Obstet Gynecol. 1989 Jan. 73(1):11-2. [Medline].
Fleischer AC, Stein SM, Cullinan JA, Warner MA. Color Doppler sonography of adnexal torsion. J Ultrasound Med. 1995 Jul. 14(7):523-8. [Medline].
Peña JE, Ufberg D, Cooney N, Denis AL. Usefulness of Doppler sonography in the diagnosis of ovarian torsion. Fertil Steril. 2000 May. 73(5):1047-50. [Medline].
Zanforlin Filho SM, Araujo Júnior E, Serafini P, Guimarães Filho HA, Pires CR, Nardozza LM, et al. Diagnosis of ovarian torsion by three-dimensional power Doppler in first trimester of pregnancy. J Obstet Gynaecol Res. 2008 Apr. 34(2):266-70. [Medline].
Kimura I, Togashi K, Kawakami S, Takakura K, Mori T, Konishi J. Ovarian torsion: CT and MR imaging appearances. Radiology. 1994 Feb. 190(2):337-41. [Medline].
Siegelman ES, Outwater EK. Tissue characterization in the female pelvis by means of MR imaging. Radiology. 1999 Jul. 212(1):5-18. [Medline].
Van Kerkhove F, Cannie M, Op de Beeck K, Timmerman D, Pienaar A, Smet MH, et al. Ovarian torsion in a premenarcheal girl: MRI findings. Abdom Imaging. 2007 May-Jun. 32(3):424-7. [Medline].
Chang HC, Bhatt S, Dogra VS. Pearls and pitfalls in diagnosis of ovarian torsion. Radiographics. 2008 Sep-Oct. 28(5):1355-68. [Medline].
Smorgick N, Pansky M, Feingold M, Herman A, Halperin R, Maymon R. The clinical characteristics and sonographic findings of maternal ovarian torsion in pregnancy. Fertil Steril. 2009 Dec. 92(6):1983-7. [Medline].
Auslender R, Shen O, Kaufman Y, Goldberg Y, Bardicef M, Lissak A, et al. Doppler and gray-scale sonographic classification of adnexal torsion. Ultrasound Obstet Gynecol. 2009 Aug. 34(2):208-11. [Medline].
Shadinger LL, Andreotti RF, Kurian RL. Preoperative sonographic and clinical characteristics as predictors of ovarian torsion. J Ultrasound Med. 2008 Jan. 27(1):7-13. [Medline].
Mashiach R, Melamed N, Gilad N, Ben-Shitrit G, Meizner I. Sonographic diagnosis of ovarian torsion: accuracy and predictive factors. J Ultrasound Med. 2011 Sep. 30(9):1205-10. [Medline].
Gittleman AM, Price AP, Goffner L, Katz DS. Ovarian torsion: CT findings in a child. J Pediatr Surg. 2004 Aug. 39(8):1270-2. [Medline].
Duigenan S, Oliva E, Lee SI. Ovarian torsion: diagnostic features on CT and MRI with pathologic correlation. AJR Am J Roentgenol. 2012 Feb. 198(2):W122-31. [Medline].
Moore C, Meyers AB, Capotasto J, Bokhari J. Prevalence of abnormal CT findings in patients with proven ovarian torsion and a proposed triage schema. Emerg Radiol. 2009 Mar. 16(2):115-20. [Medline].
Cano Alonso R, Borruel Nacenta S, Díez Martínez P, María NI, Ibáñez Sanz L, Zabía Galíndez E. Role of multidetector CT in the management of acute female pelvic disease. Emerg Radiol. 2009 Nov. 16(6):453-72. [Medline].
Lam A, Nayyar M, Helmy M, Houshyar R, Marfori W, Lall C. Assessing the clinical utility of color Doppler ultrasound for ovarian torsion in the setting of a negative contrast-enhanced CT scan of the abdomen and pelvis. Abdom Imaging. 2015 Oct. 40 (8):3206-13. [Medline].
Kawakami K, Murata K, Kawaguchi N, Furukawa A, Morita R, Tenzaki T, et al. Hemorrhagic infarction of the diseased ovary: a common MR finding in two cases. Magn Reson Imaging. 1993. 11(4):595-7. [Medline].
MacDuff R, Anthony GS, MacLennan AC. Ovarian torsion diagnosed by MRI. J Obstet Gynaecol. 2007 Oct. 27(7):743-4. [Medline].
Asfour V, Varma R, Menon P. Clinical risk factors for ovarian torsion. J Obstet Gynaecol. 2015 Aug 19. 1-5. [Medline].