ACR Appropriateness Criteria® Second and Third Trimester Bleeding

Abstract

Vaginal bleeding occurring in the second or third trimesters of pregnancy can variably affect perinatal outcome, depending on whether it is minor (i.e. a single, mild episode) or major (heavy bleeding or multiple episodes.) Ultrasound is used to evaluate these patients. Sonographic findings may range from marginal subchorionic hematoma to placental abruption. Abnormal placentations such as placenta previa, placenta accreta and vasa previa require accurate diagnosis for clinical management. In cases of placenta accreta, magnetic resonance imaging is useful as an adjunct to ultrasound and is often appropriate for evaluation of the extent of placental invasiveness and potential involvement of adjacent structures. MRI is useful for preplanning for cases of complex delivery, which may necessitate a multi-disciplinary approach for optimal care.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every two years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Animal Models to Study Placental Development and Function throughout Normal and Dysfunctional Human Pregnancy

“…77 Contrast-enhanced ultrasound imaging strategies have been reported for characterizing intervillous blood flow 78,79 ; unfortunately this technique is not capable of characterizing the entire placenta due to restrictions in the achievable field of view. 80 MRI is currently used in human pregnancies typically to evaluate fetal abnormalities and in some instances to evaluation abnormal placentation, [81][82][83] yet the use of MRI to measure placental perfusion in humans is limited. 80 There have been limited studies using MRI in conjunction with diffusion weighting, arterial spin labeling, and manipulation of oxygen concentration to create blood-oxygenation-levelbased contrast to characterize maternal placental vascular structure, [84][85][86][87][88][89] but these methods currently have not provided spatial and quantitative characterization of the maternal perfusion of the placental intervillous space.…”

Vasa praevia: a case report and literature review

“…In order to differentiate from the cervix-uterine varicose veins, a transvaginal colour doplerometry method is employed to compare the blood flow in these veins, to the fetus and the mother's blood flow. In the case of vasa praevia, the blood flow will be the same as the umbilical cord blood flow (14).…”

“…It is necessary to administer medication targeted at the fetal lung maturation (5). This is a high-risk pregnancy as along with the growing fetus, the likelihood of premature leakage of amniotic fluid or fetal blood loss is also increasingly growing (10), thus the fetal lung maturation with dexamethasone should be performed from the 28th to the 32nd week (5,10,14,15). In the case of clinical signs, a pregnant woman shall be admitted to hospital immediately, the fetal condition shall be monitored by a continuous fetal cardio-monitor, if possible, the concentration of fetal hemoglobin in the blood shall be determined (10).…”

“…The indications of completing the pregnancy via the emergency Caesarean section are as follows: labour activity, preterm leakage of amniotic fluid, unstable fetal condition -variable recurring decelerations recorded by a nonstress test, which persist through the introduction of tocolysis. Other indications may be as follows: bleeding from the uterus, fetal tachycardia, sinusoidal type of fetal heart rate, fetal anemia, confirmed by Apt or Kleihauer-Betke tests (14). A lower transverse laparotomy and a uterine incision in the lower uterine segment are performed after taking into account the 3D ultrasound images where the leading blood vessels are visualised seeking to reduce the possibility of damaging them (18).…”

MRI of Acute Gynecologic Conditions

“…Ultrasound is the imaging modality of choice, but abruption can be subacute, which can confound ultrasound findings. In stable patients without fetal distress, MRI may be an alternative modality to diagnose abruption and define the size and location of the periplacental hematoma . DWI is the most sensitive sequence for detection of placental abruption, with 100% sensitivity, followed by T 1 ‐weighted sequences, with 94% sensitivity .…”