{"paper_id":"fef10a40-bf4b-43c1-ab16-643f3dea5da4","body_text":"Abstract\nBackground: Endometriomas and functional hemorrhagic cysts (FHCs) are a common gynecological encounter.\nObjective: This study aimed to assess the diagnostic efficiency of magnetic resonance imaging (MRI) using signal intensity measurements in differentiating endometriomas from FHCs.\nMethods: Forty-six patients who underwent pelvic MRI examinations (endometriomas, n=28; FHCs, n=18) were retrospectively included. The “T2 shading” sign was evaluated subjectively and quantitatively by measuring the T1-T2 signal intensity difference and calculating the percentage of signal decrease between T1 and T2-weighted sequences. The resulted values, along with the measurement of the Apparent Diffusion Coefficient (ADC) and the signal intensity on three diffusion- weighted sequences (DWI) (b50, b400, and b800), were compared between groups by using the Mann–Whitney U test. Also, the receiver operating characteristic analysis was performed for the statistically significant results (P<0.016), and the area under the curve (AUC) was also calculated.\nResults: The two quantitative assessment methods showed similar efficiency in detecting endometriomas (P<0.001; sensitivity, 100%; specificity, 81.82%; AUC>0.86), outperforming the classic subjective evaluation of the “T2 shading” sign (sensitivity, 92.86%; specificity, 66.67%). ADC (P=0.52) and DWI measurements (P=0.49, P=0.74, and P=0.78) failed to distinguish between the two entities.\nConclusion: The quantitative analysis and interpretation of the “T2 shading” sign can significantly improve the differential diagnosis between endometriomas and FHCs.\nKeywords: Apparent Diffusion Coefficient (ADC), diffusion-weighted imaging, endometrioma, endometriosis, Magnetic Resonance Imaging (MRI), ovarian cyst.\n[http://dx.doi.org/10.1007/s00261-015-0465-1] [PMID: 26063071]\n[http://dx.doi.org/10.1177/0284185115609805] [PMID: 26543051]\n[http://dx.doi.org/10.1016/j.mefs.2015.08.001]\n[http://dx.doi.org/10.7863/jum.2002.21.8.879] [PMID: 12164573]\n[http://dx.doi.org/10.1371/journal.pone.0149465] [PMID: 26907919]\n[http://dx.doi.org/10.1007/s13244-015-0455-4] [PMID: 26671276]\n[http://dx.doi.org/10.1007/s00330-005-2882-y] [PMID: 16155722]\n[http://dx.doi.org/10.1148/radiol.2241010361] [PMID: 12091683]\n[http://dx.doi.org/10.1148/radiology.212.1.r99jl455] [PMID: 10405714]\n[http://dx.doi.org/10.1148/radiology.180.1.2052726] [PMID: 2052726]\n[http://dx.doi.org/10.1148/radiol.13131394] [PMID: 24475842]\n[http://dx.doi.org/10.1148/radiology.186.2.8421756] [PMID: 8421756]\n[http://dx.doi.org/10.1002/jmri.20640] [PMID: 16791858]\n[http://dx.doi.org/10.1016/j.clinimag.2015.05.003] [PMID: 25986161]\n[http://dx.doi.org/10.1148/radiol.10100213] [PMID: 20505067]\n[http://dx.doi.org/10.1097/OGX.0000000000000157] [PMID: 25769433]\n[http://dx.doi.org/10.1159/000334002] [PMID: 8842166]\n[http://dx.doi.org/10.1177/1933719115570907] [PMID: 25676579]\n[http://dx.doi.org/10.1148/radiology.189.1.8372185] [PMID: 8372185]\n[http://dx.doi.org/10.1097/00004728-199407000-00019] [PMID: 8040448]\n[http://dx.doi.org/10.1097/00001703-200312000-00011] [PMID: 14624220]\n[http://dx.doi.org/10.1148/radiographics.21.1.g01ja14193]\n[http://dx.doi.org/10.2214/AJR.06.1403] [PMID: 17515386]","source_license":"CC0","license_restricted":false}