Adnexal Torsion in the Third Trimester

A 41-year-old woman presented with acute, severe left-sided abdominal pain and vomiting at 37 weeks' gestation. Her symptoms were attributed to renal colic, and she was admitted for supportive treatment. During her admission, she went into spontaneous labour. Due to other obstetric indications, the team proceeded with delivery by emergency caesarean section. Intra-operatively, a necrotic left fallopian tube and ovary were identified, and a diagnosis of adnexal torsion (AT) was recognised. There was no return of tissue perfusion on de-torsion, and a left salpingo-oopherectomy was performed. AT in pregnancy is unusual, with only a minority of cases occurring in the third trimester. This is a challenging diagnosis to establish and requires a high index of suspicion. Ultrasound and magnetic resonance imaging can be helpful in establishing a diagnosis but should not delay definitive treatment. Prompt surgical intervention is paramount to prevent irreversible damage to ovarian tissue.

Endometriosis MR mimickers: T1-hyperintense lesions

Endometriosis is a chronic and disabling gynecological disease that affects women of reproductive age. Magnetic resonance imaging (MRI) is considered the cornerstone radiological technique for both the diagnosis and management of endometriosis. While MRI offers higher sensitivity compared to ultrasonography, it is prone to false-positive results, leading to decreased specificity. False-positive findings can arise from various T1-hyperintense conditions on fat-suppressed T1-weighted images, resembling endometriotic cystic lesions in different anatomical compartments. These conditions include hemorrhage, hyperproteic content, MRI artifacts, feces, or melanin. Such false positives can have significant implications for patient care, ranging from incorrect diagnoses to unnecessary medical or surgical interventions and subsequent follow-up. To address these challenges, this educational review aims to provide radiologists with comprehensive knowledge about MRI criteria, potential pitfalls, and differential diagnoses, ultimately reducing false-positive results related to T1-hyperintense abnormalities.Critical relevance statementMRI has a 10% false-positive rate, leading to misdiagnosis. T1-hyperintense lesions, observed in the three phenotypes of pelvic endometriosis, can also be seen in various other causes, mainly caused by hemorrhages, high protein concentrations, and artifacts.Key points• MRI in endometriosis has a 10% false-positive rate, leading to potential misdiagnosis.• Pelvic endometriosis lesions can exhibit T1-hyperintensity across their three phenotypes.• A definitive diagnosis of a T1-hyperintense endometriotic lesion is crucial for patient management.• Hemorrhages, high protein concentrations, lipids, and artifacts are the main sources of T1-hyperintense mimickers.

Clinical Utility of Diffusion-Weighted Imaging in Gynecological Imaging: Revisited

ABSTRACT

Diffusion-weighted imaging (DWI) is an increasingly valuable sequence in daily clinical practice, providing both functional and morphological information. The use of DWI can help quantify diffusion using the apparent diffusion coefficient, which reflects the physiological features of the tissue and tumor microcirculation. This knowledge is crucial for understanding and interpreting gynecological imaging. This article reviews the clinical utility of DWI for gynecological imaging, highlighting its ability to aid in the detection of endometrial and cervical cancers, as well as tumor extension and metastasis. In addition, DWI can easily detect the solid components of ovarian cancer (including dissemination), assist in the diagnosis of adnexal torsion, and potentially show bone marrow status. Apparent diffusion coefficient measurement is useful for differentiating between endometrial lesions, uterine leiomyomas, and sarcomas, and may provide important information for predicting the prognosis of gynecological cancers.

Successful pregnancy-preserving laparoscopic adnexectomy for complicated ovarian torsion during late pregnancy: A case report and review of the literature

INTRODUCTION AND IMPORTANCE

A rare disorder called ovarian torsion (OT) during pregnancy can harm both the mother and the fetus. Predisposing variables for the condition include enlarged ovaries, free mobility, and a long pedicle, despite the fact that its genesis is not entirely understood. When ovarian stimulation is used to treat infertility, the disease's incidence rises. Magnetic resonance imaging and ultrasound are examples of diagnostic imaging modalities (MRI).

CASE PRESENTATION

A 26-year-old woman with a 33-week pregnancy presented to our emergency department with acute, severe left groin pain. Laboratory evaluation was unremarkable except for leukocytosis (18.800/μL) with neutrophil shift. A radiologist used ultrasound to examine the abdomen and pelvis, and the results revealed a bulk enlargement of the left adnexa. The patient underwent a non-enhanced MRI in order to obtain a conclusive diagnosis, which revealed a massive enlargement and torsion of the left ovary with large areas of necrosis. The patient underwent a successful laparoscopic adnexectomy with preservation of the pregnancy. She delivered a healthy baby and had an uneventful follow up period.

DISCUSSION

The etiology of OT is largely unknown. Any tendency to rotate the infundibulopelvic and utero-ovarian ligaments should be considered as a possible etiology. The prevalence of OT among pregnant women is underreported and determined by small limited studies.

CONCLUSION

Ovarian torsion should be included in the differential diagnosis of patients with suspected acute abdomen in advanced stages of pregnancy. In addition, MRI should be used as an alternative diagnostic modality in patients with normal sonographic findings.

Scoring system for predicting ovarian necrosis in adnexal torsion using an ultra-short optimized MRI protocol

PURPOSE

To evaluate a MRI scoring system predicting haemorrhagic necrosis in adnexal torsion with intraoperative and/or histopathological correlation using an abbreviated and optimized MRI protocol.

METHODS

This retrospective observational study includes patients with adnexal torsion who underwent Magnetic Resonance Imaging(MRI) and surgery. T2 sequences were evaluated by three observers of varying experience for following findings: Hypo-intensity of ovarian stroma, around the follicle, cyst wall or ovarian capsule and the twisted pedicle. Hypo-intensities in the above and a thick cyst wall were considered as predictors of necrosis. A scoring system was created based on the number of positive findings. MRI was correlated with intraoperative and histopathological findings. Lesions showing haemorrhagic necrosis were considered true positives.

RESULTS

43 women with torsion were included. 74.4% were secondary to a lead point and 25.4% were without one. Hypointensity score of 2 or more had the highest diagnostic accuracy and inter-reader agreement in predicting necrosis (R1-sensitivity: 92%, specificity: 89%, positive predictive value (PPV): 92% and negative predictive value (NPV): 89%, R2-sensitivity: 92%, specificity: 94%, PPV: 96% and NPV: 90% and R3-sensitivity: 92%, specificity: 83%, PPV: 89% and NPV: 89%).

CONCLUSION

In patients with suspected adnexal torsion, optimized MRI using T2 weighted sequences will serve as a rapid and effective single imaging modality for diagnosing adnexal torsion and accurately predicting necrosis thereby triaging the patients for appropriate management.

Computed Tomography Features of Adnexal Torsion: A Meta-Analysis

OBJECTIVES

We performed a meta-analysis of studies examining the computed tomography (CT) features of adnexal torsion (AT).

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library for studies involving the proportion of CT features in patients with AT and that used surgery as the reference test. Study quality was assessed using the Newcastle-Ottawa scale and the Agency for Healthcare Research and Quality tool.

RESULTS

Twelve articles involving 483 patients were included. The pooled proportion of right-sided adnexal lesion was 54% (95% confidence interval [CI]: 49%-56%). The pooled proportions of the ovarian lesion histopathological types were: benign germ cell tumors, 33% (95% CI: 28%-37%); benign cystic lesions, 26% (95% CI: 21%-30%); benign epithelial neoplasms, 24% (95% CI: 20%-29%); sex cord-stromal tumors, 4% (95% CI: 2%-6%); borderline neoplasms, 3% (95% CI: 1%-6%); and hemorrhagic cysts, 2% (95% CI: 0%-3%). The pooled proportions of CT features were: Adnexal enlargement, 99% (95% CI: 98%-99%); adnexal with mass, 98% (95% CI: 97%-100%); twisted pedicle, 81% (95% CI: 78%-83%); mass with thickened wall, 77% (95% CI: 73%-81%); tubal thickening, 73% (95% CI: 68%-77%); abnormal location of adnexa, 69% (95% CI: 63%-75%), pelvic ascites, 43% (95% CI: 38%-49%); pelvic fat infiltration, 41% (95% CI: 34%-48%); uterine deviation, 37% (95% CI: 31%-42%); and lack of enhancement, 20% (95% CI: 14%-25%).

CONCLUSION

Adnexal enlargement, adnexal mass, and twisted pedicle may be the most important CT features for diagnosing AT.

ACR Appropriateness Criteria® Postmenopausal Acute Pelvic Pain

Acute pelvic pain is a common presenting complaint in both the emergency room and outpatient settings. Pelvic pain of gynecologic origin in postmenopausal women occurs less frequently than in premenopausal women; however, it has important differences in etiology. The most common causes of postmenopausal pelvic pain from gynecologic origin are ovarian cysts, uterine fibroids, pelvic inflammatory disease, and ovarian neoplasm. Other etiologies of pelvic pain are attributable to urinary, gastrointestinal, and vascular systems. As the optimal imaging modality varies for these etiologies, it is important to narrow the differential diagnosis before choosing the initial diagnostic imaging examination. Transabdominal and transvaginal ultrasound are the best initial imaging techniques when the differential is primarily of gynecologic origin. CT with intravenous (IV) contrast is more useful if the differential diagnosis remains broad. MRI without IV contrast or MRI without and with IV contrast, as well as CT without IV contrast may also be used for certain differential considerations. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Preoperative CT image-based assessment for estimating risk of ovarian torsion in women with ovarian lesions and pelvic pain

PURPOSE

To define and weight the preoperative CT findings for ovarian torsion and to develop an integrated nomogram for estimating the probability of ovarian torsion in women with ovarian lesion and pelvic pain.

METHODS

This retrospective study included 218 women with surgically resected ovarian lesions who underwent preoperative contrast-enhanced CT for pelvic pain from January 2014 to February 2019. Significant imaging findings for torsion were extracted using regression analyses and a regression coefficient-based nomogram was constructed. The diagnostic performance with sensitivity, specificity, and accuracy of the significant imaging findings and the nomogram were assessed.

RESULTS

A total of 255 ovarian lesions (123 lesions with torsion and 132 lesions without torsion) were evaluated. Multivariable regression analysis showed that whirl sign (odds ratio [OR] 11.000; p < 0.001), tubal thickening (OR 4.621; p = 0.001), unusual location of ovarian lesion (OR 2.712; p = 0.020), and hemorrhagic component within adnexal lesion (OR 2.537; p = 0.028) were independent significant parameters predicting ovarian torsion. Tubal thickening showed the highest sensitivity (91.1%) and whirl sign showed the highest specificity (94.7%). When probabilities of ovarian torsion of 0.5 or more in the nomogram were diagnosed as ovarian torsion, sensitivity, specificity, and accuracy of the nomogram were 78.1%, 91.7%, and 85.1%, respectively.

CONCLUSION

The whirl sign, tubal thickening, unusual location of ovarian lesion, and hemorrhagic component within adnexal lesion, and an integrated nomogram derived from these significant findings can be useful for predicting ovarian torsion.

Adnexal Torsion: Review of Radiologic Appearances

Adnexal torsion is the twisting of the ovary, and often of the fallopian tube, on its ligamental supports, resulting in vascular compromise and ovarian infarction. The definitive management is surgical detorsion, and prompt diagnosis facilitates preservation of the ovary, which is particularly important because this condition predominantly affects premenopausal women. The majority of patients present with severe acute pain, vomiting, and a surgical abdomen, and the diagnosis is often made clinically with corroborative US. However, the symptoms of adnexal torsion can be variable and nonspecific, making an early diagnosis challenging unless this condition is clinically suspected. When adnexal torsion is not clinically suspected, CT or MRI may be performed. Imaging has an important role in identifying adnexal torsion and accelerating definitive treatment, particularly in cases in which the diagnosis is not an early consideration. Several imaging features are characteristic of adnexal torsion and can be seen to varying degrees across different modalities: a massive, edematous ovary migrated to the midline; peripherally displaced ovarian follicles resembling a string of pearls; a benign ovarian lesion acting as a lead mass; surrounding inflammatory change or free fluid; and the uterus pulled toward the side of the affected ovary. Hemorrhage and absence of internal flow or enhancement are suggestive of ovarian infarction. Pertinent conditions to consider in the differential diagnosis are a ruptured hemorrhagic ovarian cyst, massive ovarian edema, ovarian hyperstimulation, and a degenerating leiomyoma. Online supplemental material is available for this article. ^©RSNA, 2021.

Accuracy of imaging modalities for adnexal torsion: a systematic review and meta-analysis

BACKGROUND

Adnexal torsion (AT), a serious gynaecological emergency, often presents with non-specific symptoms leading to delayed diagnosis.

OBJECTIVE

To compare the test accuracy of ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI) to diagnose AT.

SEARCH STRATEGY

We searched EMBASE, MEDLINE and Cochrane CENTRAL until December 2019.

SELECTION CRITERIA

Studies reporting on the accuracy of any imaging modality (Index Test) in female patients (paediatric and adult) suspected of AT compared with surgical diagnosis and/or standard clinical/radiological follow-up period until resolution of symptoms (Reference Standard).

DATA COLLECTION AND ANALYSIS

We assessed study quality using QUADAS-2. We conducted test accuracy meta-analysis using a univariate model or a hierarchical model.

MAIN RESULTS

We screened 3836 citations, included 18 studies (1654 women, 665 cases), and included 15 in the meta-analyses. Ultrasound pooled sensitivity (n = 12, 1187 women) was 0.79 (95% CI 0.63-0.92) and specificity was 0.76 (95% CI 0.54-0.93), with negative and positive likelihood ratios of 0.29 (95% CI 0.13-0.66) and 4.35 (95% CI 2.03-9.32), respectively. Using Doppler with ultrasound (n = 7, 845 women) yielded similar sensitivity (0.80, 95% CI 0.67-0.93) and specificity (0.88, 95% CI 0.72-1.00). For MRI (n = 3, 99 women), the pooled sensitivity was 0.81 (95% CI 0.63-0.91) and specificity was 0.91 (95% CI 0.80-0.96). A meta-analysis for CT was not possible with two case-control studies and one cohort study (n = 3, 232 women). Its sensitivity range was 0.74-0.95 and specificity was 0.80-0.90.

CONCLUSIONS

Ultrasound has good performance as a first-line diagnostic test for suspected AT. Magnetic resonance imaging could offer improved specificity to investigate complex ovarian morphology, but more evidence is needed.

TWEETABLE ABSTRACT

To investigate adnexal torsion, ultrasound is a good first-line diagnostic test with a pooled sensitivity of 0.79 and specificity of 0.76.

Added value of MRI for the diagnosis of adnexal torsion in children and adolescents after inconclusive ultrasound examination

PURPOSE

The purpose of this study was to assess the performance of magnetic resonance imaging (MRI) in children and adolescents with suspected adnexal torsion (AT) after inconclusive initial ultrasound examination.

MATERIALS AND METHODS

Twenty-eight girls with a mean age of 12±4 (SD) years (range: 1 month to 18years) were included. All had clinically suspected AT and inconclusive initial ultrasound findings followed by pelvic MRI as a second-line imaging modality. The final diagnosis was obtained by surgery or follow-up. Two radiologists blinded to the clinical, ultrasound and surgical data, retrospectively and independently reviewed MRI examinations. Clinical and MRI features associated with AT were searched for using univariate analyses.

RESULT

Among the 28 patients, 10/28 patients (36%) had AT and 22/28 (79%) had an ovarian or tubal mass. AT was associated with an age<13years (OR: 10.7; 95% CI: 1.3-148.2) (P=0.022) and a whirlpool sign at MRI (OR: 61.0; median unbiased estimate, 7.2) (P<0.0001). When a mass was present, the best quantitative MRI criteria for AT were mass volume and ovary-corrected volume≥30cm³ (κ=0.72 and 0.61, respectively), mass axis length≥5cm (κ=0.90), and mass surface area≥14 cm² (κ=0.58), with moderate to almost perfect interobserver agreement. The overall sensitivity, specificity and accuracy of MRI for the diagnosis of AT were 100% (10/10; 95% CI: 69-100), 94% (17/18; 95% CI: 73-100) and 96% (27/28; 95% CI: 82-100) respectively, with perfect interobserver agreement (κ=1).

CONCLUSION

In pediatric patients with suspected AT and inconclusive initial ultrasound examination, a strategy including MRI as a second-line imaging modality should be considered if MRI does not delay a potential surgery.

Whirlpool sign of adnexal torsion on CT: where can we find it?

Background

Whirlpool sign on computed tomography (CT) is pathognomic of adnexal torsion.

Purpose

To evaluate the visibility and common location of the whirlpool sign in adnexal torsion on CT.

Material and Methods

This retrospective study included 143 consecutive patients who underwent preoperative CT imaging and subsequent surgically confirmed as adnexal torsion. Two readers independently recorded the presence and location of whirlpool sign in adnexal torsion on CT. Patients with and without whirlpool sign were compared with regard to the size of the adnexal mass and the degree of torsion.

Results

Whirlpool sign was detected in 60 (42.0%) patients on the transverse CT plane and 79 (55.2%) patients on the coronal CT plane of 143 patients. The sign was significantly better detected on the coronal CT plane than on the transverse CT plane ( P = 0.03). The most common location of the sign included the posterolateral aspect of the adnexal mass on the transverse CT plane (25/60, 41.7%, P = 0.04) and the upper-lateral aspect of the adnexal mass on the coronal CT plane (45/79, 60.0%, P < 0.001). The size of the adnexal mass with whirlpool sign was significantly larger than the mass without whirlpool sign on the transverse CT plane (median 9.6 vs. 8.6 cm, P = 0.03). No significant difference in the degree of torsion was found between patients with and without whirlpool sign on CT ( P = 0.56–0.62).

Conclusion

Whirlpool sign of adnexal torsion is well detected at the upper-lateral aspect of adnexal mass on the coronal CT plane.

Adnexal torsion in the third trimester of pregnancy: a case report and diagnostic value of MR imaging

BACKGROUND

The torsion of normal adnexa is rare during pregnancy, especially in the third trimester. Nonspecific symptoms and signs as well as the limitations of ultrasound (US) make the diagnosis difficult, resulting in the loss of adnexa and fetal compromise. The magnetic resonance imaging (MRI) features of the torsion of normal adnexa are not classically described during pregnancy and only reported in a few cases. We find some different MRI features of the torsion of normal adnexa in late pregnancy and its diagnosis and treatment values are discussed in our report.

CASE PRESENTATION

A 27-year-old woman at 31 + 5 weeks' gestation presented to the emergency department with a three-day history of the left lower abdominal pain. US discovered a mass of 87 × 61 mm in the left abdomen, but did not show whether the mass originated from the left ovary or the uterus. MRI showed the left ovary was increased in size to 82 × 42 × 85 mm with peripheral follicles. On fat-suppressed T2-weighted images, the signal intensity of the lesion was significantly decreased compared with the right ovary. The adjacent fallopian tube was found to be thickened. The radiologists diagnosed ovary infarction secondary to adnexal torsion. With the provisional diagnosis of adnexal torsion, the patient was taken to surgery. The left adnexal torsion was found during surgery. There was extensive hemorrhage and necrosis, so a left salpingo-oophorectomy was performed. The histopathology confirmed an extensively hemorrhagic fallopian tube and ovary with partial necrosis.

CONCLUSION

We believe MRI is helpful where US is indeterminate in diagnosis of the torsion of normal adnexa in advanced pregnancy. We found that aside from hyperintensity on fat-saturated T1-weighted images, the low signal intensity on T2-weighted images can also reflect adnexal hemorrhage in conjunction with the torsion of normal adnexa.

A rare condition in the third trimester of pregnancy: Ovarian torsion

Ovarian torsion (OT) during pregnancy is a rare condition that can cause maternal and fetal morbidity. Although the etiology of the disease is not fully understood, predisposing factors include increased ovarian size, free mobility, and long pedicle. The incidence of the disease increases after ovarian stimulation for the treatment of fertility. Diagnostic imaging modalities include ultrasonography and magnetic resonance imaging (MRI). A 28-year-old woman with a 33-week pregnancy presented to our emergency department with acute, severe left groin pain. According to the patient's declaration, she had her first pregnancy, which was acquired by intrauterine insemination in another center. Her vital signs were unremarkable except for tachycardia. Physical examination revealed guarding (défense musculaire) and rebound tenderness on the left lower quadrant of the abdomen. Laboratory and imaging studies were performed for the preliminary diagnosis of acute abdomen. She was diagnosed with OT and admitted to the department of obstetrics and gynecology. OT should be included in the differential diagnosis of patients with suspected acute abdomen in advanced stages of pregnancy. In addition, MRI should be used as an alternative diagnostic modality in patients with normal sonographic findings.

Pelvic hemorrhagic lesions in women: MRI findings and differential diagnosis

A large spectrum of pathologic pelvic conditions can present with hemorrhage in structures or organs. These may present acutely, subacutely, chronically or as incidental findings. Clinical history and MRI characteristics can often narrow the differential diagnosis and guide management. The purpose of this article is to showcase a wide array of pelvic lesions, in which the presence of blood is a key imaging feature, and their differential diagnosis.

Laparoscopic Adnexal Detorsion in a 20-Week Pregnant Patient: A Case Report and Literature Review

Adnexal torsion is a cause of severe pelvic pain in reproductive aged women and during pregnancy. Adnexal torsion occurs when there is a complete turn of the ovary, tube, or both resulting in impaired blood flow to the ovary. The diagnosis of adnexal torsion is sometimes challenging due to the enlarged effect of the uterus, the displacement of abdominal and pelvic structures and the nonspecific symptoms in pregnancy. Therefore, prompt diagnosis is essential for better maternal and neonatal outcomes. The gold standard for confirmation and treatment of ovarian torsion is surgery. Laparoscopy and Laparotomy are surgical options with defined risks and benefits. Therefore, choosing the best surgical technique and surgical procedure are of utmost importance to decrease the chances of adverse events intra and postoperatively. Little literature exists regarding the laparoscopic approach of an ovarian torsion during the second trimester. Our case is a 20-week pregnant patient who had a 1080 degree rotation of the left adnexa. She required laparoscopy for adnexal detorsion and had good intraoperative, postoperative, maternal, and neonatal outcomes following management.

A case of torsion of a normal ovary in the third trimester of pregnancy: MRI findings with emphasis on asymmetry in the diameter of the ovarian veins

A 33-year-old woman, gravida two para one, at 31 weeks of gestational age experienced sudden onset of left lower quadrant pain and underwent unenhanced pelvic MRI. On fast imaging employing steady state precession (FIESTA) sequence images, a marked difference was observed in the diameters of the right and left ovarian veins. The right ovarian vein was torturous and dilated, measuring 35 mm in diameter, while the left ovarian vein was thin and linear, measuring 7 mm in diameter. The left ovary showed no apparent swelling or hemorrhage, but was suspected to have been shifted anteriorly. The patient underwent explorative laparotomy and was found to have left ovarian torsion. A difference in diameter of the ovarian veins, with thinning of the twisted side and compensatory dilatation of the contralateral side for drainage of increased uterine blood flow, may be a useful imaging sign for the diagnosis of ovarian torsion during pregnancy.

Auto-amputated adnexa in a young woman: Multimodal imaging to rule in a pelvic rolling stone

We report the case of a 26-year-old woman with a right auto-amputated adnexa and a free-floating mass in the pouch of Douglas using multimodal imaging studies including ultrasonography, computed tomography, and magnetic resonance imaging. The absence of an ovary and the evidence of an amorphous and potentially calcified mass, with no connection to the genital tract - in particular when it is found to be mobile - are the key imaging findings. Prospective diagnosis of adnexal auto-amputation could assist surgeons in patient management with a curative laparoscopy in symptomatic women, or potentially expectant management in young women who are asymptomatic or have unrelated symptoms.

Analysis of Clinical and Ultrasound Determinants of Adnexal Torsion in Children and Adolescents

STUDY OBJECTIVE

We aimed to assess the performance of transabdominal ultrasonography (US) for diagnosis of adnexal torsion (AT) in children and adolescents and evaluate its clinical and US determinants. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: We retrospectively (2004-2014) studied data for children referred for acute or subacute pelvic pain who underwent US and included children 3 months to 18 years old who underwent surgical exploration and/or clinical and radiological follow-up for at least 3 months. The evaluation of US diagnostic performance was on the basis of the proposed diagnosis after US: AT or no AT with or without mass. Clinical and US predictors of AT were identified using regression analysis.

RESULTS

Among 65 girls included (mean age 11.75 ± 4.49 years), 33 (50.8%) had AT. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of US for AT were 90.9%, 68.7%, 75%, 88%, and 80%, respectively. Overall, 20 of 33 (60.6%) AT patients had a mass, including 33% with mature teratomas. Patients with AT versus no AT more frequently showed vomiting (64% vs 28%; P = .008), ovarian edematous stroma with a peripheral distribution of follicles (45.5% vs 9.4%; P = .002) and a mass of pluritissular aspect (40% vs 0%; P < .0001). The quantitative US predictors of AT were total area ratio (ovary and mass)/area of the contralateral ovary 4.9 or greater (P = .0002) and surface area 18.5 cm² or greater (P = .0003).

CONCLUSION

US has high sensitivity but low specificity for the diagnosis of AT in children. The predictive criteria are vomiting, presence of a pluritissular mass, 4.9 area ratio or greater, or surface area 18.5 cm² or greater.

Magnetic resonance imaging performance for diagnosis of ovarian torsion in pregnant women with stimulated ovaries

Background

To determine if asymmetric ovarian edema on non-contrast MRI can be used to distinguish torsed from non-torsed stimulated ovaries in pregnant women.

Methods

In this retrospective study, our radiology database was searched for women who were pregnant and who had undergone ovarian stimulation and underwent MRI abdomen/pelvis from 1/2000–12/2012. At our institution, ultrasound is typically performed as a first line study for pregnant women with pelvic pain, with MR for those patients with indeterminate findings. 64 pregnant women (gestational age range 3–37 weeks) were included. MRI indication, prospective interpretation, operative diagnosis, and follow-up were recorded. Two blinded radiologists (with a third radiologist tie-breaker) independently measured and described the ovaries, including the likelihood of torsion. If one or both ovaries/adnexa had an underlying lesion such as a dermoid, cystadenoma, or abscess, the patient was excluded from size and signal intensity comparison (N = 14). For the remaining 50 women, comparison was made of the ovaries in women with normal ovaries (N = 27), stimulated ovaries without torsion (N = 11), non-stimulated ovaries with torsion (N = 3), and stimulated ovaries with torsion (N = 3). Patients with asymmetric ovarian edema without stimulation or torsion (N = 3) and with polycystic ovary syndrome (N = 3) were analyzed separately.

Results

Average normal ovarian length was 3.2 cm, compared to 4.5 cm for asymmetric edema and 5.6–8.8 cm for the other four groups. Average difference in greatest right and left ovarian diameter was 19% for normal ovaries compared to 24–37% for the other 5 groups. Asymmetric signal on T2-weighted imaging (T2WI) was seen in 12% (3/27) of normal ovaries compared to 9% (1/11) of stimulated patients without torsion, 33% (1/3) of patients with PCOS and 67% (2/3) of patients with torsion both without and with stimulation. The correct diagnosis of torsion was made prospectively in 5/6 cases but retrospectively in only 3/6 cases. In patients with stimulation, correct diagnosis of torsion was made in 2/3 cases prospectively (both with asymmetric T2 signal) and retrospectively in only 1/3 cases. In 13/64 patients, other acute gynecologic and non-gynecologic findings were diagnosed on MRI.

Conclusions

Enlarged edematous ovary can be seen with ovarian stimulation, ovarian torsion, or both. Although asymmetric ovarian edema occurred more frequently in patients with torsion than without, in pregnant patients with stimulated ovaries referred for MRI (typically after non-diagnostic ultrasound), ovarian torsion could not be confidently diagnosed or excluded retrospectively with non-contrast MRI.

Usefulness of T2*-weighted MRI in the detection of adnexal torsion

Background

The usefulness of T2*-weighted (T2*W) imaging for the detection of adnexal torsion has yet to be determined.

Purpose

To assess the usefulness of T2*W imaging for detecting and differentiating adnexal torsion.

Material and Methods

Eight patients with eight ovaries with torsion and 44 patients with 72 ovaries without torsion were included in this study. All patients underwent 1.5-T magnetic resonance imaging (MRI) including T2*W images. The frequency and distribution of hypointensity on T2*W images were compared between ovaries with torsion and ovaries without torsion.

Results

Hypointensity on T2*W images was significantly more frequent in ovaries with torsion than in ovaries without torsion (75% vs. 36%; P < 0.05). Among patients with hypointensity on T2*W images, the frequency of diffuse hypointensity was significantly higher in ovaries with torsion than in ovaries without torsion (83% vs. 0%; P < 0.01); whereas the frequency of focal hypointensity was significantly lower in ovaries with torsion than in ovaries without torsion (17% vs. 100%; P < 0.01).

Conclusion

The presence and distribution of hypointensity on T2*W images may play a supplementary role in the detection of adnexal torsion.