6–9 October 2013, Sydney, Australia Oral communication abstracts OC17.06 Comparison of measurements of the uterus and cervix obtained by MRI and ultrasound imaging used for planning radiotherapy for cervix cancer S. van Dyk 1 , S. Kondalsamy-Chennakesavan 2 , K. Narayan 3 , M. Schneider 4 1 Radiation Therapy Services, Peter MacCallum Cancer Centre, East Melbourne, VIC, Australia; 2 Rural Clinical School, The University of Queensland, Toowoomba, QLD, Australia; 3 Division of Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, VIC, Australia; 4 Department of Medical Imaging and Radiaiton Science School of Biomedical Science, Monash University, Clayton, VIC, Australia Objectives: To determine if ultrasound can be used to guide radiotherapy planning and treatment of cervix cancer. Methods: Data from patients undergoing curative treatment with radiotherapy between January 2007 and March 2012 were analysed. Patients underwent spinal or general anaesthesia while intrauterine applicators were inserted into the uterine canal. The applicators facilitate internal radiation treatment (brachytherapy). Images were obtained in the longitudinal axis of the uterus with the applicator in-situ. Measurements were taken at the anterior and posterior surface of the uterus at 2.0 cm intervals along the applicator, from the external os to the tip of the applicator. MRI and US measurements were compared using descriptive statistics. Mean differences (MD) less than 3 mm in cervix and 5 mm in uterus were deemed not clinically significant. Results: One hundred and ninety nine patients contributed 1728 measurements. Differences between US and MRI measurements were US<MRI 54%, US>MRI 34%, US=MRI 12%. MD and 95% CI limits for each measurement are shown in Figure 1. The MD of measurements to the posterior surface of the uterus were within ±3 mm. The MD of measurements to the anterior surface of the uterus were within ±5 mm. Conclusions: Unlike MRI, US is an accessible and economical imaging modality that is suitable for all patients. US can be used to guide radiotherapy planning as it can identify the uterine surface within clinically acceptable limits. Supporting information can be found in the online version of this abstract OC17.07 Application research of real time sono-elasticity imaging in cervical cancer J. Geng, J. Tang Department of Gynecology, Peking University People’s Hospital, Beijing, Beijing, China Objectives: To conduct a research on the value of applying Assisted Stress Elasticity Imaging and Acoustic Stress Elasticity Imaging inthe diagnosis of cervical cancer. Methods: Assisted Stress e Sie Touch Elasticity (ETE) imaging and Virtual Touch Tissue Quantification (VTQ) technology were used to examine lesions of 44 cases of cervical cancer and 50 cases of normal cervix. Images and measurement values were recorded and statistical analysis was performed. Results: The ETE diagnosis of cervical cancer achieved a sensitivity of 88.6%, and a specificity of 94%. The VTQ mean value of cervical cancer is 2.68±0.49m/s, which is significantly greater than that of normal cervix of 1.53±0.47m/s (P<0.05). Conclusions: Both ETE and VTQ examinations showed that the lesion hardness of cervical cancer increased significantly. The more advanced stage the cervical cancer is, the higher the lesion hardness will be, which indicates that there is value of applying real time elasticity imaging in the diagnosis of cervical cancer. OC17.08 Endometrial cancer diagnosis: pattern evaluation at transvaginal ultrasound and gel infusion sonography versus endometrial sample, hysteroscopy and MRI M. Dueholm 1 , E. Marinovskij 3 , C. Møller 1 , S. Rydbjerg 1 , E. Hansen 2 , G. Ørtoft 1 1 Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark; 2 Department of Pathology, Aarhus University Hospital, Aarhus, Denmark; 3 Department of Diagnostic Imaging, Aarhus University Hospital, Aarhus, Denmark Objectives: To evaluate the diagnostic efficiency of identification of endometrial cancer by pattern recognition at TVS (transvaginal ultrasonography) and GIS (gel infusion sonography) and to compare these results to those of ES (endometrial samples), MRI (magnetic resonance imaging), and HY (hysteroscopy). Methods: consecutive women with postmenopausal bleeding and an endometrial thickness ≥5 mm were included (72 endometrial cancer). Observers were blinded to prior pathology and imaging. Endometrial patterns were evaluated by TVS with Doppler, GIS and at HY(HYpattern) for diagnosis of malignancy. Malignant myometrial invasion (<50%) was evaluated at the same time at TVS, GIS and MRI. Resectoscopic samples (HYbiopsy) and hysterectomy served as reference standards. Diagnostic efficiency for diagnosis of benign and malignant pathology for each diagnostic strategy (TVS, GIS, HY, MRI) was evaluated and compared. Results: TVS and GIS had high diagnostic efficiency (area under the curve (AUC)(CI95%)) for diagnosis of malignancy (TVS 88, (83–93); GIS 92, (87–96)) comparable to ES (90, (85–96), HYpattern (93, (89–96)), and MRI (87, (82–92)). HYbiopsy was most efficient (98, (96 – 100) (p<0.05). The efficiency of ES as a first- step techniques (39 failures of ES not included, but 22 insufficient ES included as possible malignant). AUC was 76 (69–84) at ES and lower than at TVS (p=0.02). Evaluation of myometrial invasion at TVS and GIS achieved AUC of 81, which was comparable to MRI. Only one of twenty-six patients with deep myometrial involvement was not identified as cancer by GIS. Conclusions: Endometrial pattern evaluation at TVS and GIS may correctly classify nine of ten patients with benign or malignant endometrium; myometrial invasion may be evaluated during the same procedure and without prior knowledge of cancer. These methods should be evaluated in future studies. The techniques may aid faster diagnosis and efficient, correct patient selection for minimally invasive treatment. OC18: ANEUPLOIDY AND SECOND TRIMESTER FETAL ANOMALIES II OC18.01 The prenasal thickness to nasal bone length ratio: 2D versus 3D ultrasound E. de Jong 1 , F. Vos 3 , K. Kagan 2 , L.S. Ribbert 1 , E. Tromp 1 , C.M. Bilardo 3 1 Fetal Medicine Unit, Saint Antonius Hospital, Nieuwegeing, Netherlands; 2 Fetal Medicine Unit, University of Tubingen, Tubingen, Germany; 3 Fetal Medicine Unit, University Medical Centre Groningen, Groningen, Netherlands Objectives: Recently we showed that the prenasal thickness to nasal bone length ratio (PT:NBL) measured in 3D volumes of the Ultrasound in Obstetrics & Gynecology 2013; 42 (Suppl. 1): 1–47. 35