Sonogaphically Indeterminate Adnexal Masses: Advantage of MRI

Transcription

1 Sonogaphically Indeterminate Adnexal Masses: Advantage of MRI Poster No.: C0792 Congress: ECR 2013 Type: Scientific Exhibit Authors: S. Magu, M. Goyal, N. Jain, S. Agarwal ; Rohtak, Ha/IN, , ha/in, Rohtak, Haryana/IN Keywords: Pelvis, Genital / Reproductive system female, MR, Comparative studies, Cysts DOI: /ecr2013/C0792 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 51

2 Purpose Adnexal masses are a common clinical problem, an estimated 510% of women undergo 1 surgery for suspicious adnexal masses, less than 25% prove to be malignant. Ultrasonography (US) is accepted as the primary modality in the evaluation of women with suspected adnexal mass because of its widespread availability, relatively low 2 cost and high sensitivity in detection of masses. Most gynecologists accept US results 3 when determining if need exists for further diagnostic evaluation. Transvaginal US has 4 further improved the resolution for imaging of adnexal masses.although sonography has been shown to be sensitive method it is limited by its decreased specificity leading to 2 indeterminate sonographic diagnosis. Besides clinical examination laparoscopy with histologic evaluation of biopsy material is 4,5 the generally accepted gold standard for diagnosis of ovarian tumors. A disadvantage is its invasiveness; patients with benign tumors are subjected to an unnecessary procedure. 6,7 Computed Tomography (CT) is another option as an additional imaging technique. Because of its relatively poor soft tissue contrast, the usefulness of CT in differentiating 3 ovarian process is limited. Magnetic Rresonance Imaging (MRI) has been shown to have potential in accurate charcterization of ovarian masses. The high accuracy of MRI in identifying the origin of adenexal mass and characterizing its solid, hemmoraghic,fatty, fibrous content may 7 obviate surgery or significantly contribute to preoperative planning before surgery. With this background, the present study is being undertaken to evaluate the role of MRI in characterization of sonographically indeterminate adnexal masses. Methods and Materials A prospective study was performed with patients having clinically suspected adnexal masses presenting to Gynaecologic department between May 2007 to April Twenty four women having mean age of 45 years (range 16 to 84 years) who had 30 sonographically indeterminate adnexal masses composed the final study population. Mass was considered sonographically indeterminate if it fulfilled one or more of the Page 2 of 51

3 following criterias: Suboptimal image quality, Large mass / difficulty in determining origin of mass, Purely solid mass, Purely cystic mass, Complex solid cystic mass. Female patients with known metastatic disease, pregnant females or patients having contraindication for MRI were excluded from the study. The final diagnosis for 29 of the 30 masses was established on the basis of surgical and pathological findings. One diagnosis was confirmed on Digital subtraction angiography. IMAGING MODALITIES Sonography All cases were subjected to high resolution sonography examination. Abdominal and pelvic examination was performed with full urinary bladder using 25 MHz sector probe. All married females were examined with 59MHz transvaginal probe as per requirements (empty bladder). MRI All 24 MRI studies were performed on a 1.5T scanner. Before the administration of contrast, axialt1w/tse, T2W/TSE, T2W/STIR, T2W/FFE; coronalt1w/tse, T2W/ TSE, T2W/STIR; Sagittal T2W/TSE sequences were obtained with a slice thickness varying between 1mm to 4mm. Contrast enhanced images were obtained immediately after the IV hand injection of Gadolinium Dimeglumine at a dose of 10 ml given at the rate of 2 ml per second. Using these raw data, post processing was done with the help of in built software. Image Analysis The ultrasound images were evaluated prospectively to determine the following features of a mass: Origin (uterine, ovarian, extraovarian extrauterine, tubal), Tissue content (solid, purely cystic, solid cystic / multicystic), Character of solid masses (Hypoechoic, hyperechoic, heteroechoic & Presence or absence of vascularity), Character of cystic masses (Wall thickness, mural nodule, internal echogenicity), Character of solid cystic / multicystic masses (Septa, papillary excrescences, solid component) Twenty four MRI studies were reviewed. The reviewers were aware of the history of sonographically indeterminate adnexal mass but were blinded to sonography findings. The following factors were assessed in each patients: number of patients, Origin (uterine, ovarian, extrauterine extraovarian, tubal), Tissue content (solid, purely cystic, Page 3 of 51

4 multicystic / solid cystic). For determining tissue content and tissue characterization, the signal characteristics of the mass on T1 and T2weighted images were documented as being hypointense, hyperintense, or isointense to skeletal muscle; and the presence of fat, hemorrhage, and fibrous or leiomyomatous tissue was recorded. Fat was identified if a mass showed high signal intensity on T1weighted images and lost signal intensity on fatsuppressed T1weighted sequences. Hemorrhage was identified if a mass showed high signal intensity on both nonfatsuppressed and fatsuppressed T1weighted images. Fibrous and leiomyomatous tissue was defined as being hypointense to skeletal muscle on T2weighted images as previously documented. A thick enhancing wall, internal enhancement, septations, and mural nodules within the mass were used to help characterize a mass as benign or malignant. Results Twenty four female patients in the age group of 1684years with maximum patients rd th in 3 to 6 decade were evaluated by ultrasound and MRI. Seventeen patients were premenopausal and seven were postmenopausal. No. of patient with benign masses No. of patient with malignant masses Premenopausal(n=17) 13/17 4/17 Postmenopausal(n=7) Table 1. Menstrual status 4/7 3/7 Table 2.Clinical symptoms (24 cases) Symptoms No. of patients Pain abdomen 11 Mass felt per abdomen 4 Abdominal distension 3 Menorrhagia 3 Urinary retention 2 Infertility 1 Imaging findings ULTRASONOGRAPHY : Page 4 of 51

5 All the patients underwent both transabdominal and transvaginal (only married females) ultrasonography. Findings are summarized in the following tables TABLE 3 Organ of origin of adnexal masses on US and comparison with the final diagnosis (n=30, 24 cases) Frequency in all Final diagnosis masses on US Uterine Ovarian (21 masses) 0 cases, 3/ /30 (23 cases) 24/30 Tubal 1/30 1/30 Extraovarian 0 2/30 Extrauterine TABLE 4 Tissue content of the masses on US and comparison with final diagnosis (n=30, 24 cases) Frequency in all masses Final diagnosis (no. of cases) on US (no. of cases) Predominantly solid 14 (11) 9 (8) Purely cystic 4 (4) 9 (7) Multicystic / solid cystic 12 (9) 12 (9) TABLE 5 Echogenicity of the solid lesions (n=14, 11 cases) Frequency in all Frequency in Frequency in masses benign masses malignant masses Hypoechoic 6/14 (42.8%) 2/10 (20%) 4/4 (100%) Page 5 of 51

6 Hyperechoic 1/14 (7.2%) 1/10 (10%) 0/4 (0%) Heteroechoic 7/14 (50%) 7/10 (70%) 0/4 (0%). TABLE 6 US features in predominantly solid masses Flow characterization of solid lesions on color Doppler sonography (n=14, 11 cases) Frequency in all Frequency in Frequency in masses benign masses malignant masses Present 8/14 (57.1%) 4/10 (40%) 4/4 (100%) Absent 6/14 (42.9%) 6/10 (60%) 0/4 (0%) TABLE 7 US features* in purely cystic adnexal masses (4 cases, 4 masses) Frequency in benign masses Wall thickness 2/4 (50%) <3mm 2/4 (50%) >3mm Mural Nodule 1/4 (25%) Present 3/4 (75%) Absent Int. echogenicity 1/4 (25%) Anechoic 3/4 (75%) Low echogenicity contents 0 (0%) High echogenicity contents 8 9 * Modified from scoring system proposed by Sassone et al (as modified by Joshi et al ). Page 6 of 51

7 TABLE 8 US features in multicystic / solid cystic masses (n=12, 9 cases) Frequency in all Frequency in Frequency in masses benign masses malignant masses Septa 9/12 (75%) 6/7 (85.7%) 3/5 (60%) 6/9 (66.6%) 6/6 (100%) 0/3 (0%) 3/9 (33.3%) 0/6 (0%) 3/3 (100%) 3/12 (25%) 1/7 (14.3%) 2/5 (40%) 5/12 (41.6%) 0/7 (0%) 5/5(100%) 7/12 (58%) 7/7 (100%) 10/12 (83.3%) 5/7 (71.4%) 2/12 (16.7%) 2/7 (28.6%) Present <3mm >3mm Absent Papillary excrescences Present 0/5 (0%) Absent Solid component 5/5(100%) Present 0/5 (0%) Absent MRI MRI examination was done on a 1.5Tesla machine. AxialT1W/TSE, T2W/TSE, T2W/STIR, T2W/FFE; coronalt1w/tse, T2W/TSE, T2W/STIR; Sagittal T2W/TSE sequences were done precontrast with a slice thickness varying between 1mm to 4mm. 10ml of Gadolinium dimeglumine was given at the rate of 2ml/s followed by saline flush at the rate of 2ml/s and then axial T1WCE; coronal T1WCE and sagittal T1CE sequences were obtained TABLE 9 Organ of origin of adnexal masses on MRI and comparison with the final diagnosis (n=30, 24 Cases) Page 7 of 51

8 Frequency in all masses Final diagnosis on MRI Uterine 3/30 3/30 Ovarian 26/30 24/30 Tubal 0 1/30 Extraovarian 1/30 2/30 Extrauterine MRI wrongly categorized two cases i.e. pyosalpinx and pelvic schwannoma as possibly ovarian. In our study MRI correctly classified all 30 adnexal masses. Nine out of 30 masses were predominantly solid, 9 were purely cystic and 12 masses were multicystic or solid cystic. Characteristics of solid masses on MRI Signal intensity characters, enhancement patterns of solid adnexal masses were analysed. TABLE 10 MR characteristics of solid adnexal masses Case No. T1W T2W Enhancement 2 Hypointense Heterogenous with few cystic areas Leiomyoma uterus 8 Heterogenous Heterogenous with few cystic areas Leiomyosarcoma of uterine origin 21 Hypointense Heterogenous with few cystic areas Leiomyoma uterus 4 Isointense to Hypointense No hypointense with few cystic enhancement areas Ovarian fibroma 5 Heterogenous Poorly differentiated Heterogenous with few cystic areas Final diagnosis Page 8 of 51

9 ovarian malignancy 6 Hypointense Intermediate Bilateral dysgerminoma 13 Hypointense Heterogenous with few cystic areas Schwannoma 15 Hypointense Heterogenous with few cystic areas Neurofibroma Characteristics of purely cystic mass on MRI TABLE 11 MR characteristics of purely cystic masses Case No. T1W T2W Calcification Fat Hemorr Wall hagic Thickcomponent ness Final diagnosis Enhancement 9 Hypointense Hyperintense >3mm Ovarian abscess 11 Hypointense Hyperintense (in nodule) <3mm Cystic teratoma 16 Hypointense Hyperintense >3mm Pyosalpinx 17 Hypointense Intermediate to Hyperintense >3mm Ovarian abscess 19 Hyperintense Hyperintense >3mm Dermoid 20 Hypointense Hyperintense <3mm Simple ovarian cyst 24 Hyperintense Hypointense with hypointense areas >3mm Endometriotic cysts Characteristics of multicystic / solid cystic masses on MRI. Page 9 of 51

10 TABLE 12 MR characteristics of multicystic / solid cystic masses Case No. T1W T2W Enhance Septa Papillary Solid Final excrescences component diagnosis ment 1 Mixed Mixed signal intensity >3mm Papillary serous cystadenocarcinoma 3 Mixed Mixed >3mm Mucinous cystadenocarcinoma 7 Hypo Heterogenous with hyperintense areas <3mm Granulosa cell tumor 10 Hypo Mixed signal intensity with central hyperintense area Papillary serous cystadenocarcinoma 12 Hypo Hyper with multiple septations <3mm Serous cystadenoma 14 Mixed Mixed <3mm Mucinous cyst adenoma 18 Mixed Mixed with with hyperintense hyperintense componentcomponent with fat fluid level <3mm teratoma 22 Mixed >3mm Papillary serous cystadeno carcinoma Mixed Page 10 of 51

11 23 Hypo Heterogenous with multiple tortuous vessels Ovarian arteriovenous malformation HISTOPATHOLOGIC FINDINGS Histopathology was the gold standard in our study. Out of 24 cases, 23 were subjected to histopathological examination for final diagnosis and 1 case was confirmed on digital subtraction angiography (ovarian arteriovenous malformation). TABLE 13 No. of cases Intrauterine Masses 2 Leiomyoma 1 Leiomyosarcoma Ovarian masses 1 Ovarian fibroma 2 Ovarian abscess 3 Teratoma 1 Simple ovarian cyst 1 Endometriosis 1 Serous cystadenoma 1 Mucinous cystadenoma 1 Granulosa cell tumor 3 Papillary serous cystadenocarcinoma 1 Mucinous cystadenocarcinoma 1 Poorly differentiated ovarian malignancy 1 Dysgerminoma 1 Page 11 of 51

12 Ovarian AV malformation Tubal 1 Pyosalpinx Extrauterine extraovarian 1 Schwannoma 1 Neurofibroma TABLE 14 Comparison of US classification with pathologic findings in 24 ovarian masses for diagnosis of malignancy US Total No. Pathologic findings Benign Malignant Benign 8 7 (true negative) 1 (false negative) Malignant 16 8 (false positive) 8 (true positive) Thus, US had a sensitivity of 89%, specificity of 46.7%, positive predictive value of 50% and negative predictive value 83.3% for the diagnosis of malignancy in ovarian masses. TABLE 15 Comparison of MRI classification with pathologic findings in 24 ovarian masses for diagnosis of malignancy MRI Total No. Pathologic findings Benign Malignant Benign (true negative) 0 (false negative) Malignant 10 1 (false positive) 9 (true positive) For diagnosis of malignancy in ovarian masses, MRI had a sensitivity of 100%, specificity of 93.3%, positive predictive value 90% and negative predictive value 100%. Images for this section: Page 12 of 51

13 Fig. 1: CASE 2 45 year female presented with menorrhagia for one month. US shows a large, mixed echogenicity mass behind urinary bladder Page 13 of 51

14 Fig. 2: Coronal T1 image lesion is hypointense Page 14 of 51

15 Fig. 3: Coronal T2 weighted image shows large lobulated well defined heterogenous mass with few hyperintense area in pelvis arising from posterior wall of uterusleiomyoma Page 15 of 51

16 Fig. 4: CASE 8 28 year female presented with excessive bleeding per vaginum for three months. US shows large hypoechoic mass in the pelvis on right side with color flow on doppler Page 16 of 51

17 Fig. 5: Axial T2W images shows heterogenous mass with illdefined borders arising from uterine wall Page 17 of 51

18 Fig. 6: Axial T2W/FFE sequence clearly demonstrate continuity of mass with uterusleiomyosarcoma Page 18 of 51

19 Fig. 15: Axial T1W image shows the lesion to be hypointense. NEUROFIBROMA Page 19 of 51

20 Fig. 14: Axial T2W images shows the lesion to be heterogenous with a hyperintense area Page 20 of 51

21 Fig. 7: CASE4 70 year old postmenopausal female presented with lump abdomen US shows well defined large solid hypoechoic adnexal mass on right side of pelvis.uterus is normal Page 21 of 51

22 Fig. 8: The lesion is very hypointense on coronal T2W images with few interspersed hyperintense areas OVARIAN FIBROMA Page 22 of 51

23 Page 23 of 51

24 Fig. 10: Post contrast image shows strong homogenous enhancement of both the masses. BILATERAL DYSGERMINOMA Page 24 of 51

25 Page 25 of 51

26 Fig. 9: CASE 6 16 YEAR OLD FEMALE PRESENTED WITH LUMP ABDOMEN Saggital T2W MR image shows two large solid masses of intermediate signal intensity with low signal intensity septa Fig. 11: CASE year old female presented with complain of retention of urine US shows a well defined hypoechoic mass on left side of pelvis Page 26 of 51

27 Fig. 13: CASE year old hysterectomized female presented with pain abdomen US shows heteroechoic mass on right side of pelvis posterior tp urinary bladder Page 27 of 51

28 Fig. 12: Axial T2W MR image shows a heterogeneously hyperintense mass with few cystic area posterior to uterus.pelvic SCHWANNOMA Page 28 of 51

29 Fig. 26: CASE year old postmenopausal women presented with abdominal distension for one month. US shows large solid cystic masses in bilateral adenexa with central cystic areas with solid projections, Ascites also seen Page 29 of 51

30 Fig. 27: Axial T2W images show bilateral adenexal masses with internal heterogencity with irregular solid component and florid intracystic papillary projection. PAPILLARY SEROUS CARCINOMA Page 30 of 51

31 Fig. 28: CASAE old female presented with pain abdomen US shows a large multiloculated mass with numerous thin septation.cystic locules are showing echoes of variable echogenecity.hyperechoic lesion is seen within the cystic locule not attached to the wall Page 31 of 51

32 Fig. 29: T2W image shows large multiloculated mass with locules showing varying signal intensities.no solid component seen. MUCINOUS CYST ADENOMA Page 32 of 51

33 Fig. 30: CASE year old female presented with pain abdomen. US showed solid cystic mass in left adnexa, color doppler showed vascularity in mass with multiple vessel surrounding the mass(not shown) CT shows hypodense lesion on left side of pelvis with serpiginous enhancing area in it. Page 33 of 51

34 Fig. 31: Axial T2W image shows blooming of hyperintense signal within the vessel on TEW/FFE sequence. Fig. 17: Coronal T2W image shows two thick walled lesion with left sided dominant hyperintense signal and right sided lesion lesion showing mixed signal intensity. Page 34 of 51

35 Fig. 25: Coronal T2W IMAGE shows heterogenous mass with multiple hyperintense areas within the tumor classically described as 'sponge like' appearance. GRANULOSA CELL TUMOR OF OVARY Page 35 of 51

36 Fig. 24: case year old hysterectomized(for prolapse uterus) female presented with retention of urine US shows a well defined heteroechoic mass in pelvis with multiple small cystic areas Page 36 of 51

37 Fig. 23: The masses shows evidence of shading/blooming on T2W/FFE sequence suggestive of presence of blood and blood product. BILATERAL ENDOMETRIOTIC CYSTS Page 37 of 51

38 Fig. 22: CASE year old female presented with pain abdomen. US shows two well defined solid masses in bilateral adenexa, color doppler showed no flow in the lesion(not shown) Page 38 of 51

39 Fig. 21: Axial T1W SPIN ECHO MR image obtained with frequency selective fat saturation shows low signal intensity of the central portion (confirming the presence of fat)cystic TERATOMA Page 39 of 51

40 Fig. 20: Axial T2W images shows well defined thick walled high signal intensity adenexal mass.bicornuate uterus also seen. Page 40 of 51

41 Fig. 19: CASE year old female presented with pain lower abdomen. US shows an ill defined hyperechoic lesion in the pelvis, exact extent of the lesion is not clear Page 41 of 51

42 Fig. 16: CASE year old female presented with pain abdomen. US shows two thick walled solid looking masses in bilateral adenexa. uterus is normal Page 42 of 51

43 Fig. 18: Post contrast image shows wall enhancement. OVARIAN ABSCESSES Page 43 of 51

44 Page 44 of 51

45 Fig. 32: MR angiography depict tangle of tortuous vessels in left adnexa arising from left internal iliac artery and draining into left ovarian vein. OVARIAN ARTERIOVENOUS MALFORMATION. Page 45 of 51

46 Conclusion Adnexal masses are a common clinical problem; an estimated 510% of women undergo surgery for suspicious adnexal masses, less than 25% of which prove to be malignant. 1 US remains the imaging modality of choice in the assessment of the female pelvis, 10 because it is readily available, inexpensive, safe and quick. Despite the high sensitivity 11 of US, it is rarely specific. Outwater and Dunton revealed that unnecessary surgery was performed in 50 67% of benign cases because of suspicious sonographic findings. Hence the value of reassuring the patient that a sonographically detected ovarian mass 2 is not a malignancy but a benign mass cannot be underestimated. These issues justify the need to recognize which sonographic findings routinely result in an indeterminate or suspicious diagnosis and to determine whether MRI is the 2 appropriate next step. Many reports in the literature indicate that MRI is useful in 1,2,3,10 evaluating the female pelvis and it has been recommended for further evaluation of ultrasonographically indeterminate pelvic masses. However there are few published data demonstrating objective evidence thatmri is beneficial after an equivocal US examination. Our study reveals that sonography performs poorly for determining the origin of the mass, which is the essential first step in characterizing an adnexal mass. For example, differentiating a pelvic mass that is intimately relating to uterus as a pedunculated subserosal leiomyoma or ovarian tumor can be difficult with US. This is particularly true 10 if mass is large and/or is distorting or obscuring the uterus. In our study, sonography wrongly categorized all uterine masses as ovarian. Large mass size was an additional contributing factor to an indeterminate sonography diagnosis. Hence, these large solid 2,10 pelvic masses remain diagnostic dilemmas on sonography. With MRI, the anatomy of the uterus is clearly seen because the high signal endometrium on T2 weighting is easily differentiating from the surrounding low signal junctional zone and myometrium. 10 Excellent agreement was seen between MRI and the final proven origin of all masses of uterine origin in our study. This stresses MRI as the best next step in evaluating such a mass before subjecting a patient to surgery which might be unnecessary. Our results in accurately characterizing an adnexal mass as a pedunculating uterine mass are similar to those reported in prior MR studies. 12,13 Because fibrous tumor of the ovary have imaging features similar to those of fibroid such as low signal intensity on T2W images the recognition of stalk of fibroid & identification of separate normal ovaries help confirm the diagnosis of a fibroid. 13,14 Page 46 of 51

47 Our study showed that accurate tissue characterization, the second essential component of characterizing an adnexal mass, was poor for sonography and excellent of MRI. The entire spectrum of benign and malignant pelvic masses appeared solid on sonography in our study, and benign masses sometimes appeared complex on sonography, thereby mimicking a malignancy. In our study two endometriomas, one dermoid and two ovarian abscesses were incorrectly categorized as solid ovarian neoplasms on US. MRI was particularly useful in revealing the character of these lesions. High signal intensity on T1W & low signal intensity ("shading") on T2W images were highly specific for endometriotic cysts. 2,3 Teratomas typically showed hyperintense signal on both T1W and T2W images 15,16,17,18 with characteristic low signal intensity on fat suppressed images. In our study MRI proved extremely useful in characterizing ovarian abscesses as thick walled lesions with layering of internal echoes and debris which were wrongly labeled as solid ovarian masses on sonography. Unenhanced T1 & T2 weighted imaging is important for accurate tissue characterization. Lipid and blood are readily detected on T1 weighted imaging with and without fat 11,16,19,20 suppression. T2weighted imaging helps to identify the relatively low signal intensity of endometriomas, reflecting blood degradation products from repeated cyclical bleeding 11 or the very low signal intensity of fibrous tissue in a fibrous tumor of 16 the ovary (e.g. fibroma). Gadolinium is usually reserved for improved delineation of papillary projections, solid component, nodules and thick enhancing septations in ovarian 16,21,22 cancers. Our study confirms that contrast enhanced MRI (CEMR) performs better than US in 23,24,25 characterizing adnexal masses. Both techniques are highly sensitive for detection of malignancy, but CEMR is more specific than US for diagnosis of malignancy resulting in a large number of false positive cases on US. In our study US falsely labeled 8 benign adnexal masses as malignant masses (8 false positives). As in previous series US false positive diagnosis were mainly in the case of endometriotic cysts, dermoids and 23,24,25 ovarian abscesses. We evaluated multiple imaging features to determine the best predictors of malignancy. Solid cystic lesions are more likely to be malignant where as 26 purely solid or purely cystic lesions are more likely to be benign. In our study the most significant features that favoured the diagnosis of malignancy were (a) solid mass or large solid component (b) Septa greater than 3mm thick and/or presence of vegetations or nodularity. However unlike a thick septa, a thick lesion wall did not indicate malignancy. 15 In our study, the all thick lesions (2 endometriomas, 1 dermoid, 2 ovarian abscesses) were found to be benign. Secondary features such as ascites, peritoneal disease, or 15 lymphadenopathy were all strongly indicative of malignancy. Our study has few limitations. Because of the small sample size and the overlap of categories of reasons for a mass being indeterminate on sonography, we could not perform a statistical analysis of these data. Moreover our study also has a patient Page 47 of 51

48 selection bias. Only patients with adnexal masses were recruited from gynaecology clinic. However our subjects were patients referred in clinical practice for MR imaging evaluation of complex adnexal masses. Moreover the goal of our study was not to compare the accuracy of MRI and sonography, rather it was to evaluate the ability of MRI to provide additional useful information in cases of indeterminate sonographic findings. Our study reflects real time experience as all patients underwent surgical exploration. In summary, MR imaging is an excellent technique for the detection and characterization of adnexal mass lesions. The multi planner capability of MR imaging allows high accuracy in identifying the origin of an adnexal mass and characterizing its solid, haemorrhagic, fatty and fibrous content and may obviate surgery or significantly contribute to preoperative planning of a sonographically indeterminate mass. In addition CEMR provides a depiction of internal architecture of lesions particularly vegetation in a solid cystic lesions. Thereby differentiating benign from malignant lesions. Features highly indicative of malignancy include thick septa more than 3mm, irregularity and vegetation on wall and septa, and/ or solid component. To conclude MRI is a very sensitive modality for diagnosis of adnexal masses and is highly specific in characterization of sonographically indeterminate adnexal masses. References 1. Sohiab SA, Mills TD, Sahdev a, Webb JAW, Trappen POV, Jacobs IJ, et al. The role of magnetic resonance imaging and ultrasound in patients with adnexal masses. Clinical Radiology 2005; 60: Adusumilli S, Hussain HK, Caoili EM, Weadock WJ,Murray JP, Johnson TD, et al. MRI of sonographically indeterminate adnexal masses. AJR 2006; 187: Outwater EK, Dunton CJ. Imaging of the ovary and adnexa: clinical issues and applications of MR imaging. Radiol 1995; 194: Rieber A, Nussle K, Stohr I,Grab D, Fenchel S, Kreienberg R,et al. PreoperativE diagnosis of ovarian tumors with MR Imaging; comparison with transvaginal sonography, positron emission tomography and histologic findings. AJR 2001; 177: Miller JC. Incidentally detected adnexal masses. Radiol 2007; 5: Seltzer V. Laparoscopic surgery for ovarian lesions : potential pitfalls. Clin Obstet Ginecol 1993; 36: Page 48 of 51

49 7. Alvarez RD, Kilgore LC, Partridge EE Austin JM, Shingleton HM. Staging ovarian cancer diagnosed during laparascopy: accuracy rather than immediacy. South Med J. 1993; 86: Sassone AM, Ilan E, Tritsch T, Artner A, Westhoff C, Warren WB. Transvaginal Sonographic Characterization of Ovarian Disease: Evaluation of a New Scoring System to Predict Ovarian Malignancy. Obstet Gynaecol 1991; 78: Joshi M, Ganesan K, Munshi HN, Ganesan S, Lawande A. Ultrasound of adnexal masses. Semin Ultrasound CT MRI 2008; 29: Chang SD, Cooperberg PL, Wong AD, Llewellyn PA, Bilbey JH. Limitedsequence magnetic resonance imaging in the evaluation of the ultrasonographically indeterminate pelvic mass. Can Assoc Radiol J 2004; 55: Outwater EK, Dunton. Imaging of the ovary and adnexa:clinical issues and applications of MR imaging.radiology 199; 194: Scoutt LM, McCarthy SM, Lange R, Bourque A, Schwartz PE. MR evaluation of clinically suspected adnexal masses. J Comput Assist Tomogr 1994; 18: Weinreb JC, Barkoff ND, Megibow A, Demopoulos R. The value of MR imaging in distinguishing leiomyomas from other solid pelvic masses when sonography is indeterminate. AJR 1990;154 : Kim JC, Kim SS, Park JY. "Bridging vascular sign" in the MR diagnosis of exophytic uterine leiomyoma. J Comput Assist Tomogr 2000; 24: Sohaib AA, Sahdev A, Trappen PV, Jacobs IJ, Reznek RH. Characterization of adnexal mass lesions on MR Imaging. AJR 2003; 180: Siegelman ES, Outwater EK. Tissue characterization in the female pelvis by means of MR imaging. Radiology 1999; 212: Imaoka I, Wada A, Kaji Y, Hayashi T, Hayashi M, Matsuo M, et al. Developing an MR imaging strategy for diagnosis of ovarian masses. Radiographics 2006: 26: Jung SE, Lee JM, Rha SE, Byun JY, Jung JI, Hahn ST. CT and MR imaging of ovarian tumors with emphasis on differential diagnosis. Radiographics 2002; 22: Kier R, Smith RC, McCarthy SM. Value of lipid and watersuppression MR images in distinguishing between blood and lipid within ovarian masses. AJR 1992;158 : Page 49 of 51

50 20. Stevens SK, Hricak H, Campos Z. Teratomas versus cystic hemorrhagic adnexal lesions: differentiation with protonselective fatsaturation MR imaging. Radiology 1993;186 : Outwater EK, Huang AB, Dunton CJ, Talerman A, Capuzzi DM. Papillary projections in ovarian neoplasms: appearance on MRI. J Magn Reson Imaging 1997; 7: Van Vierzen PB, Massuger LF, Ruys SH, Barentsz JO. Borderline ovarian malignancy: ultrasound and fast dynamic MR findings. Eur J Radiol 1998; 28: Yamashita Y, Torashima M, Hatanaka Y, Harada M, Higashida Y, Takahashi M, et al. Adnexal Masses; accuracy of characterization with Transvaginal US and Precontrast and postcontrast MR Imaging. Radiology 1995; 194: Komatsu T, Konishi I, Mandai M, Togashi K, Kawakami S, Konishi J, et al. Adnexal Masses: transvaginal US and gadolinium enhanced MR imaging assessment of intratumoral structure. Radiology 1996; 198: Rieber A, Nussle K, Stohr I, et al. Preoperative diagnosis of ovarian tumors with MRI:comparison with transvaginal sonography, positron emission tomography, and histologic findings. AJR Am J Roentgenol 2001;177: Stevens SK, Hricak H, Stern JL. Ovarian lesions: detection and characterization with gadoliniumenhanced MR Imaging at 1.5 T. Radiology 1991; 181: Personal Information Sarita magu M.D is senior professor in Department of Radiology Pt. B.D sharma, PGIMS, University of health sciences, rohtak,haryana, INDIA nkmagu@rediffmail.com Monica Goyal M.D is consultant radiologist at Pushpanjali hospital, New Delhi, INDIA. drabhishekgoyal11@yahoo.in Nitin Jain M.B.B.S, D.M.R.D is senior resident in Department of Radiology Pt. B.D sharma, PGIMS, University of health sciences, rohtak, Haryana, INDIA logindrnitin@gmail.com Page 50 of 51

51 Shalini Agarwal M.D is professor in Department of Radiology Pt. B.D sharma,pgims,university of health sciences, rohtak, Haryana, INDIA Page 51 of 51