Value of fat-suppression gradient-echo MR imaging in the diagnosis of ovarian cystic teratomas

Added Value of Assessing Adnexal Masses with Advanced MRI Techniques

This review will present the added value of perfusion and diffusion MR sequences to characterize adnexal masses. These two functional MR techniques are readily available in routine clinical practice. We will describe the acquisition parameters and a method of analysis to optimize their added value compared with conventional images. We will then propose a model of interpretation that combines the anatomical and morphological information from conventional MRI sequences with the functional information provided by perfusion and diffusion weighted sequences.

Value of dynamic contrast-enhanced MRI for tissue characterization of ovarian teratomas: correlation with histopathology

AIM

To analyse the value of double contrast-enhanced (DCE) magnetic resonance imaging (MRI) in addition to conventional MRI to characterize ovarian teratomas subtypes with histological correlation.

MATERIALS AND METHODS

From January 2005 to December 2008, 38 women undergoing MRI and subsequent resection of ovarian teratomas were identified [40 mature cystic teratomas (MCT), two struma ovarii, three immature teratomas]. MRI images were analysed blindly by two radiologists according to morphological and vascular abnormalities. An experienced histopathologist reviewed all slides to determine the presence and histological composition of Rokitansky protuberances.

RESULTS

Thirty-one MCT (77%) had at least one small, regular Rokitansky protuberance presenting at an acute angle with the cyst wall. Ten out of 31 MCT did not display any enhancement on contrast-enhanced MRI related to sebaceous glands, adipose lobules, keratin, and pilosebaceous adnexa at histology. Three different time-intensity curve (TIC), types 1, 2, and 3, were related to presence of smooth muscular cells and fibrous, neuroglial, or thyroid tissue, respectively, found at histology of MCT. Type 3 TIC was also present in one struma ovarii and two immature teratomas.

CONCLUSION

TIC types are related to the specific content of the solid tissue of ovarian teratomas but cannot be used to differentiate benign and malignant ovarian teratomas.

Dynamic contrast-enhanced MR imaging of ovarian neoplasms: current status and future perspectives

MR imaging is useful for characterizing ovarian tumors. Dynamic contrast-enhanced MR imaging is a promising new technique useful for characterizing perfusion and angiogenesis of ovarian masses. This article describes the dynamic contrast-enhanced MR imaging technique examines the current and future applications of this technique in patients with ovarian tumors.

Value of magnetic resonance imaging for the diagnosis of ovarian tumors: a review

This article reviews the value of magnetic resonance imaging (MRI) for the diagnosis of ovarian tumors especially when ultrasonography is indeterminate. Although ultrasonography is the first imaging technique used to investigate suspected pelvic masses, it has a limited capacity for tissue characterization. In addition to morphological characteristics, many tissue parameters such as T1, T2, perfusion, and diffusion contribute to signal intensity, so MRI is able to identify various types of tissue contained in pelvic masses. Magnetic resonance imaging helps to locate large solid masses and to distinguish benign from malignant ovarian tumors, with an overall accuracy of 88% to 93% for the diagnosis of malignancy. The aims of this review are 3-fold. First, we review state-of-the-art and usual MRI techniques and published findings. Second, we recall the MR features most useful for assessing the main ovarian tumors. Finally, we discuss the relevance of various features for distinguishing between benign, borderline, and invasive ovarian tumors.

MR imaging compared with intraoperative frozen-section examination for the diagnosis of adnexal tumors; correlation with final histology

The aim was to compare the accuracy of magnetic resonance imaging (MRI) and intraoperative consultation (IC) for the diagnosis of adnexal masses, with reference to final histology. MRI was performed in 136 women with sonographically indeterminate adnexal masses. IC included macroscopic and frozen-section examination. Macroscopic examination and MRI determined size, nature, and presence of vegetations or solid portions within masses. All masses were characterized as benign or malignant according to previously published MR imaging and histopathologic criteria. Sensitivities, specificities, and predictive values for the diagnosis of malignancy of MRI and IC were assessed. Histology revealed 168 adnexal masses (99 benign, 23 borderline and 46 invasive). Frozen sections were examined in 151 cases. Among the 151 adnexal masses studied by both MRI and IC, respective sensitivities, specificities, positive and predictive values of both methods for the diagnosis of malignancy were 89.7% and 84.5%, 91.4% and 100%, 86.7% and 100%, and 93.4% and 91.3%. Sensitivities of MR imaging and frozen section for the diagnosis of serous versus mucinous borderline tumors were 33.3% and 93.3%, and 62.5% and 12.5%, respectively. MRI is less accurate than IC for characterizing adnexal masses. However, MRI may increase the relevance of IC for borderline mucinous tumors.

Intérêt de l'IRM associée à l'échographie pour la caractérisation des masses annexielles persistantes au cours de la grossesse : à propos de neuf cas

OBJECTIVE

To evaluate the accuracy of MR imaging combined with sonography for the diagnosis of persistent adnexal masses during pregnancy.

PATIENTS AND METHODS

From January 1999 to November 2003, nine patients with a persistent adnexal masse were included in this retrospective study. All patients underwent both transvaginal and transabdominal sonography combined with MR imaging. Accuracy of imaging techniques was evaluated by comparison with histology.

RESULTS

Adnexal masse was detected by systematic sonography in six women whereas three patients were symptomatic. Mean gestational age at the diagnosis was 17 weeks of amenorrhea (range 5-36). Mean tumor size was 96 mm (range 2-15). Two patients underwent a surgery during pregnancy; one for acute abdominal pain related to an adnexal torsion and the second for suspicion of malignancy. One patient underwent a caesarean delivery for obstetrical reasons. In all patients, benign ovarian tumours were found. For eight patients the diagnosis suspected by imaging techniques was confirmed by histology.

DISCUSSION AND CONCLUSION

The combination of sonography and MR imaging allows diagnosing accurately adnexal masses during pregnancy.