1. Follow-up scans later in pregnancy improved accreta detection but provided useful information in only a limited number of cases. Of the individual markers, the presence of placental lacunae was highly predictive for the presence of an accreta, with high sensitivities and positive predictive values. An abnormal clear space in the lower uterine segment was also a frequent finding, but its usefulness appears to be as support for other findings and, if isolated, is usually a false-positive diagnosis. The presence of multiple ultrasound findings, although not very sensitive, was also highly predictive. The question then arises whether color Doppler scanning would provide more sensitivity and specificity. The presence of lacunae that exhibit marked turbulent blood flow by color Doppler scanning, which also extend into surrounding tissues, has been examined in the third trimester. Lerner JP & al [1], found in 5 of 6 cases in which there were lacunae with turbulent flow, there was a placenta accreta. However, the authors did not state how many patients had turbulent spaces that did not extend into surrounding tissues. The use of color enhances the appearance of these vascular spaces, but it is not clear that the actual use of color increases accuracy over gray-scale observation of these abnormally shaped linear spaces. Two welldesigned studies have not found that color Doppler scanning added any additional information that could not be obtained from gray-scale ultrasonography. Levine et al [2] found that gray- scale ultrasonography was also superior to magnetic resonance imaging in the diagnosis of placenta accreta in all cases, except 1 case with a posterior accreta. None contrast-enhanced magnetic resonance imaging can sometimes confirm gray-scale ultrasound findings but has not proved to be superior because it is not possible to differentiate placenta and myometrium well. Contrast enhancement (gadolinium) does appear in some hands to make the differentiation better but in other instances has not demonstrated invasion of the myometrium, when, in fact, it existed.. Evaluate the role of Doppler ultrasound in the antenatal screening of placenta accreta. Placenta accreta is a rare condition consisting of an abnormal placental tissue infiltration of the myometrium. This anomaly of placental insertion carries a high risk of postpartum hemorrhage and should be sought in case of uterine scar. Prenatal diagnosis is essential for optimal obstetric management. Doppler ultrasound can participate in the screening. C.MRAZGUIA, M. MAROUANI, O. ZOUKAR, A. HAMMAMI, A.FALFOUL Gynecology obstetrics department, Regional Hospital of Nabeul During this period of 6 years we have collected 18 cases of placenta accreta in our service. The average age of our patients was 32 years, mean parity was 2.4. In 11 cases the diagnosis was suspected on ultrasound of the second trimester, for the other 7 patients the diagnosis was made in the third trimester. The risk factors found were uterine scar in 83.33% of cases, a history of myomectomy in 27.77%, a history of curettage in 33.33% of cases. Ultrasound has suspected placenta accreta in 14 of these patients (77.77%) showing images of placental lacunae (vascular spaces) in 10 cases (71.42%), absence of hypo echoic border security between the placenta and the myometrium in 2 cases (14.28%), interruption of the hyper echoic area at the interface between the uterine serosa in 4 cases (28.57%). Color Doppler has objectified a turbulent flow within the placental deficiencies in 8 cases. The combination of two or three of these signs clearly improves the sensitivity of this exam. MRI was performed in 6 cases (42.85%) to confirm the diagnosis. The delivery was by caesarean section in 83.3%. A hysterectomy was necessary to control bleeding in 15 cases, in three other cases, conservative treatment has been achieved. In conclusion, the 2D ultrasound examination is useful for the detection of placenta accreta, the most efficient ultrasound test is intra placental deficiencies. The Doppler is a useful tool in addition to ultrasound, especially to research vessel developed at the interface uterine serosa- bladder. MRI in patients with ultrasound suspicion of placenta accreta can improve the diagnostic performance, especially when the placenta is posterior This is a retrospective study in the department of gynecology and obstetrics in Nabeul including all cases of suspected placenta accreta for a period of six years from January 2005 to December 2010. We found that obliteration of the clear space can develop over the course of pregnancy but that the clear space alone is not a good diagnostic sign for placenta accreta. Visualization of placental lacunae was the most reliable diagnostic sign. In addition, lacunae were found as early as 15 weeks of gestation in most patients who were examined then. This is a noteworthy finding because mid second trimester is the time at which most patients have their ‘‘screening’’ ultrasound examination. [1] Lerner JP & al. Characterization of placenta accreta using transvaginal sonography and color Doppler imaging. Ultrasound Obstet Gynecol 1995;5:198-201. [2] Levine D & al. Placenta accreta: evaluation with color Doppler US, power Doppler US, and fast MR imaging. Radiology 1997;205:773-6. [3] Kayem G & al. Management of placenta accreta. BJOG 2009;116:1536-7. OB10