Placental mesenchymal disease masquerading as molar pregnancy with a favourable maternal and fetal outcome.

Placental mesenchymal dysplasia (PMD) is an exceptionally rare placental anomaly characterised by placentomegaly and grape-like vesicles resembling partial mole on ultrasonography, yet it can coexist with a viable fetus. We present the case of a primigravida who presented at 22 weeks gestation with a suspected partial mole but with a normally growing fetus. The differential diagnoses considered included placental mesenchymal disease, partial mole and twin pregnancy with molar pregnancy. With normal beta HCG levels and prenatal invasive testing reports, a probable diagnosis of PMD was made, and after thorough counselling, the decision was made to continue the pregnancy. The pregnancy progressed until 37 weeks, culminating in the uneventful delivery of a 2.4 kg healthy male infant. Histopathology confirmed PMD. Early recognition and management of PMD pose significant challenges, given its rarity. Prenatal identification of PMD during both early and late gestation could avert unnecessary termination of pregnancy.

Images in abnormal placenta: a rare case of "blood bag" formation in placenta membranacea.

Placenta membranacea is an uncommon placental anomaly. Here, we present the case of a 30-year-old primiparous woman admitted for thickened placenta and reduced amniotic fluid. A follow-up ultrasound, performed after 48 h, revealed that the placental parenchyma was thin and not adequately visualized, enclosing a substantial volume of flowing blood (150 mm), with an amniotic fluid index of 18 mm. An emergency cesarean section was promptly performed. Following fetal delivery, a substantial accumulation of dark red blood within the fetal membranes created a "blood bag", estimated at approximately 3000 ml. This observation aligned with the ultrasound findings, and both placental morphology and pathological results substantiated the diagnosis of placenta membranacea.

Placental Histopathologic Findings in the Setting of Prenatally Diagnosed Major Congenital Heart Disease.

Objectives: Studies suggest an association between placenta and congenital heart disease (CHD). We evaluated placental pathologies associated with major CHD. Methods: A prospective study included fetuses with major CHD, identified by fetal echocardiography. Fetal Doppler of umbilical artery (UA), middle cerebral artery (MCA), and placental histopathology were assessed. Outcome was measured by mortality at one month of age. Results: 21 cases were analyzed. Hypoplastic left heart syndrome was the commonest lesion (23.8%). Significant differences were detected among categories regarding MCA systolic/diastolic (S/D) ratio & pulsatility index (p = 0.023; 0.036), respectively. Placental histopathologies were demonstrated in 18(85.7%), predominately involved fetal malperfusion lesions 16/21(76.2%), especially chorangiosis (33.3%). No significant association was detected between placental histopathological abnormalities and Doppler parameter, diagnostic category, or mortality. Conclusion: The high prevalence of abnormal placental histopathological findings in major fetal CHD provides additional evidence of placental-cardiac interlinkage. No association was detected between abnormal placental histopathology and fetal Doppler measurements or neonatal outcome of CHD.

Prenatal diagnosis of bilobate placenta: incidence, risk factors and impact on pregnancy outcomes.

OBJECTIVES: To investigate the incidence and risk factors of bilobate placenta, as well as to assess its impact on preeclampsia (PE), preterm delivery (PTD) and small-for-gestational age (SGA) neonates. METHODS: A prospective study of singleton pregnancies, undergoing routine anomaly scan at 20+0-23+6 gestational weeks, was conducted, between 2018 and 2022. The impact of prenatally diagnosed bilobate placenta on PE, PTD and SGA was assessed. Multivariate logistic regression models were employed to assess the independent association between bilobate placenta and the main pregnancy outcomes, using specific confounders. Additionally, a risk factor analysis was performed. RESULTS: The study population included 6,454 pregnancies; the incidence of prenatally diagnosed bilobate placenta was 2.0 % (n=129). Bilobate placenta was associated with PE (aOR: 1.721; 95 % CI: 1.014-2.922), while no statistically significant association was found between this anatomical variation and SGA (aOR: 1.059; 95 % CI: 0.665-1.686) or PTD (aOR: 1.317; 95 % CI: 0.773-2.246). Furthermore, pregnancies with prenatally diagnosed bilobate placenta had an increased prevalence of abnormal cord insertion (marginal or velamentous) (9.8 vs. 27.1 %; p<0.001) and increased mean UtA PI z-score (0.03 vs. 0.23; p=0.039). Conception via ART (aOR: 3.669; 95 % CI: 2.248-5.989), previous history of 1st trimester miscarriage (aOR: 1.814; 95 % CI: 1.218-2.700) and advancing maternal age (aOR: 1.069; 95 % CI: 1.031-1.110) were identified as major risk factors for bilobate placenta. CONCLUSIONS: Bilobate placenta, excluding cases of co-existing vasa previa, is associated with higher incidence of PE, increased mean UtA PI z-score and higher probability of abnormal cord insertion, but not with increased risk for SGA or PTD. It is more common in pregnancies following ART and in women with a previous 1st trimester miscarriage.

Early pregnancy imaging predicts ischemic placental disease.

INTRODUCTION: To characterize early-gestation changes in placental structure, perfusion, and oxygenation in the context of ischemic placental disease (IPD) as a composite outcome and in individual sub-groups. METHODS: In a single-center prospective cohort study, 199 women were recruited from antenatal clinics between February 2017 and February 2019. Maternal magnetic resonance imaging (MRI) studies of the placenta were temporally conducted at two timepoints: 14-16 weeks gestational age (GA) and 19-24 weeks GA. The pregnancy was monitored via four additional study visits, including at delivery. Placental volume, perfusion, and oxygenation were assessed at both MRI timepoints. The primary outcome was defined as pregnancy complicated by IPD, with group assignment confirmed after delivery. RESULTS: In early gestation, mothers with IPD who subsequently developed fetal growth restriction (FGR) and/or delivered small-for gestational age (SGA) infants showed significantly decreased MRI indices of placental volume, perfusion, and oxygenation compared to controls. The prediction of FGR or SGA by multiple logistic regression using placental volume, perfusion, and oxygenation revealed receiver operator characteristic curves with areas under the curve of 0.81 (Positive predictive value (PPV) = 0.84, negative predictive value (NPV) = 0.75) at 14-16 weeks GA and 0.66 (PPV = 0.78, NPV = 0.60) at 19-24 weeks GA. DISCUSSION: MRI indices showing decreased placental volume, perfusion and oxygenation in early pregnancy were associated with subsequent onset of IPD, with the greatest deviation evident in subjects with FGR and/or SGA. These early-gestation MRI changes may be predictive of the subsequent development of FGR and/or SGA.

Management of large placental chorioangioma: two-port laser approach for fetal intervention.

OBJECTIVES: There is a paucity of literature providing evidence-based guidelines for the management of large placental chorioangioma (≥ 4 cm in diameter). The objectives of this study were to compare outcomes between patients managed expectantly and those undergoing in-utero intervention and to describe the different in-utero techniques used for cessation of blood flow to the tumor and the associated outcome. METHODS: This was a retrospective cohort study of 34 patients referred for the management of large placental chorioangioma in a single center between January 2011 and December 2022, who were managed expectantly or underwent in-utero intervention. In-utero intervention was performed when the fetus developed any signs of impending compromise, including high combined cardiac output (CCO), worsening polyhydramnios or abnormal fetal Doppler velocimetry findings. Interventions included radiofrequency ablation (RFA), interstitial laser ablation (ILA) and single-port or two-port fetoscopic laser photocoagulation (FLP). Treatment selection was dependent on the proximity of the tumor to the umbilical cord insertion (UCI) and placental location. The two-port technique was performed in patients with a chorioangioma with large feeding vessels (≥ 3 mm) located in the posterior placenta, in which one port was used for occlusion using bipolar forceps and the other port was used for laser photocoagulation of the feeding vessels downstream. The single-port technique was used for chorioangioma with small feeding vessels (< 3 mm) located in the posterior placenta. ILA or RFA was performed in cases with an anterior placenta. Supportive treatments, including amnioreduction and intrauterine transfusion (IUT), were performed for worsening polyhydramnios and suspected fetal anemia based on middle cerebral artery Doppler flow studies, respectively. Comparative statistical analysis between cases undergoing expectant management vs in-utero intervention was performed. Descriptive details were provided for patients who underwent in-utero intervention. RESULTS: Thirty-four cases of large chorioangioma were evaluated, of which 25 (73.5%) were managed expectantly and nine (26.5%) underwent intervention. The frequency of polyhydramnios was significantly higher in the intervention group compared with the expectant-management group (66.7% vs 8.0%, P < 0.001). The live-birth rate among expectantly managed cases with large chorioangioma was significantly higher compared with that in cases that underwent in-utero intervention (96.0% vs 62.5%, P = 0.01). In the intervention group, preoperative CCO was elevated in all cases with available information and preoperative hydrops was present in 33.3% (3/9) of cases. One patient experienced fetal demise following IUT prior to planned FLP. Among the remaining eight patients, four underwent two-port FLP, two underwent single-port FLP, one underwent ILA and one underwent both ILA and RFA. All three cases in which hydrops was present at the time of intervention resulted in fetal demise. CONCLUSIONS: In-utero interventions aimed at cessation of blood flow in the feeding vessels are a therapeutic option for the management of cases with large chorioangioma. The two-port percutaneous technique appears to improve the efficiency of FLP when a large chorioangioma with large feeding vessels is located in the posterior placenta. We propose that in-utero interventions for large chorioangioma should be initiated prior to the development of fetal hydrops. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Chimeric Singleton Placenta Comprising Placental Mesenchymal Dysplasia and Complete Hydatidiform Mole with Live Birth and Postpartum Diagnosis of Gestational Trophoblastic Neoplasia.

INTRODUCTION: Placental mesenchymal dysplasia (PMD) is a benign lesion that is often misdiagnosed as complete (CHM) or partial hydatidiform mole. PMD usually results in live birth but can be associated with several fetal defects. Herein, we report PMD with CHM in a singleton placenta with live birth. CASE PRESENTATION: A 34-year-old gravida 2, para 1, living 1 (G2P1L1) woman was referred on suspicion of a molar pregnancy in the first trimester. Maternal serum human chorionic gonadotrophin levels were increased during early pregnancy, with multicystic lesions and placentomegaly observed on ultrasonography. Levels decreased to normal with no fetal structural abnormalities observed. A healthy male infant was delivered at 34 gestational weeks. Placental p57KIP2 immunostaining and short tandem repeat analysis revealed three distinct histologies and genetic features: normal infant and placenta, PMD, and CHM. Gestational trophoblastic neoplasia was diagnosed and up to fourth-line chemotherapy administered. CONCLUSION: Distinguishing PMD from hydatidiform moles is critical for avoiding unnecessary termination of pregnancy. CHM coexisting with a live fetus rarely occurs. This case is unique in that a healthy male infant was born from a singleton placenta with PMD and CHM.

Placental chorioangioma and pregnancy outcome: a ten-year retrospective study in a tertiary referral centre.

BACKGROUND: Placental chorioangioma is a rare disorder in pregnancy. We retrospectively reviewed the perinatal complications and long-term outcomes in pregnancies with placental chorioangioma and evaluated the factors affecting disease prognosis. METHODS: We reviewed pregnant women who delivered at our hospital in the past decade and whose diagnosis of placental chorioangioma was confirmed by pathological diagnosis. Information on maternal demographics, prenatal sonographic findings and perinatal outcomes was obtained by reviewing the medical records. In the latter part of the study, follow-up of children was conducted by phone interview. RESULTS: In the 10 years from August 2008 to December 2018, 175 cases(0.17%) were identified as placental chorioangioma histologically and 44(0.04%) of them were large chorioangiomas. Nearly one-third of cases with large chorioangiomas were associated with severe maternal and fetal complications or required prenatal intervention. Although one-fifth of fetuses/newborns complicated with large chorioangiomas were lost perinatally, the long-term prognosis for surviving fetuses was generally good. Further statistical analysis revealed that tumor size and location affect prognosis. CONCLUSION: Placental chorioangioma may cause an unfavorable perinatal outcome. Regular ultrasound monitoring can provide the tumor characteristics which can be referred to for predicting the tendency of those complications and indicate when intervention may be necessary. It is not clear which factors lead to complications with fetal damage as the main manifestation or polyhydramnios as the main manifestation.

Fetal and placental metastases associated with maternal cancers.

PURPOSE: Review the effects of fetal and placental metastases in the setting of maternal cancer. METHOD: Data reported in the peer-reviewed literature were combined with guidelines to evaluate the incidence, type and prognosis for fetal and placental metastasis in the setting of maternal cancer. RESULTS: Limited literature available. Fetal and placental metastasis are rare. Fetal metastasis generally occurs on the background of concurrent placental metastasis thus it is important to thoroughly examine the placenta in cases of known gestational cancers. Tumor molecular testing is used to confirm maternal to offspring transmission. Maternal to offspring transmission may have a long timeline between birth to clinical presentation. Prognosis in offspring may be better than in the mother who may have a more aggressive phenotype. CONCLUSION: Fetal and placental metastasis associated with maternal cancers are rare and limited peer-reviewed literature is available. The occurrence may be confirmed by detailed histological placental evaluation and molecular testing in the offspring.

Association of intraplacental oxygenation patterns on dual-contrast MRI with placental abnormality and fetal brain oxygenation.

OBJECTIVES: Most human in-vivo placental imaging techniques are unable to distinguish and characterize various placental compartments, such as the intervillous space (IVS), placental vessels (PV) and placental tissue (PT), limiting their specificity. We describe a method that employs T2* and diffusion-weighted magnetic resonance imaging (MRI) data to differentiate automatically placental compartments, quantify their oxygenation properties and identify placental lesions (PL) in vivo. We also investigate the association between placental oxygenation patterns and fetal brain oxygenation. METHODS: This was a prospective study conducted between 2018 and 2021 in which dual-contrast clinical MRI data (T2* and diffusion-weighted MRI) were acquired from patients between 20 and 38 weeks' gestation. We trained a fuzzy clustering method to analyze T2* and diffusion-weighted MRI data and assign placental voxels to one of four clusters, based on their distinct imaging domain features. The new method divided automatically the placenta into IVS, PV, PT and PL compartments and characterized their oxygenation changes throughout pregnancy. RESULTS: A total of 27 patients were recruited, of whom five developed pregnancy complications. Total placental oxygenation level and T2* did not demonstrate a statistically significant temporal correlation with gestational age (GA) (R2 = 0.060, P = 0.27). In contrast, the oxygenation level reflected by T2* values in the placental IVS (R2 = 0.51, P = 0.0002) and PV (R2 = 0.76, P = 1.1 × 10-7 ) decreased significantly with advancing GA. Oxygenation levels in the PT did not show any temporal change during pregnancy (R2 = 0.00044, P = 0.93). A strong spatial-dependent correlation between PV oxygenation level and GA was observed. The strongest negative correlation between PV oxygenation and GA (R2 = 0.73, P = 4.5 × 10-7 ) was found at the fetal-vessel-dominated region close to the chorionic plate. The location and extent of the placental abnormality were automatically delineated and quantified in the five women with clinically confirmed placental pathology. Compared to the averaged total placental oxygenation, placental IVS oxygenation level best reflected fetal brain oxygenation level during fetal development. CONCLUSION: Based on clinically feasible dual-MRI, our method enables accurate spatiotemporal quantification of placental compartment and fetal brain oxygenation across different GAs. This information should improve our knowledge of human placenta development and its relationship with normal and abnormal pregnancy. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

SWAVE 2.0 Imaging of Placental Elasticity and Viscosity: Potential Biomarkers for Placenta-Mediated Disease Detection.

Pregnancy complications such as pre-eclampsia (PE) and intrauterine growth restriction (IUGR) are associated with structural and functional changes in the placenta. Different elastography techniques with an ability to assess the mechanical properties of tissue can identify and monitor the pathological state of the placenta. Currently available elastography techniques have been used with promising results to detect placenta abnormalities; however, limitations include inadequate measurement depth and safety concerns from high negative pressure pulses. Previously, we described a shear wave absolute vibro-elastography (SWAVE) method by applying external low-frequency mechanical vibrations to generate shear waves and studied 61 post-delivery clinically normal placentas to explore the feasibility of SWAVE for placental assessment and establish a measurement baseline. This next phase of the study, namely, SWAVE 2.0, improves the previous system and elasticity reconstruction by incorporating a multi-frequency acquisition system and using a 3-D local frequency estimation (LFE) method. Compared with its 2-D counterpart, the proposed system using 3-D LFE was found to reduce the bias and variance in elasticity measurements in tissue-mimicking phantoms. In the aim of investigating the potential of improved SWAVE 2.0 measurements to identify placental abnormalities, we studied 46 post-delivery placentas, including 26 diseased (16 IUGR and 10 PE) and 20 normal control placentas. By use of a 3.33-MHz motorized curved-array transducer, multi-frequency (80,100 and 120 Hz) elasticity measures were obtained with 3-D LFE, and both IUGR (15.30 ± 2.96 kPa, p = 3.35e-5) and PE (12.33 ± 4.88 kPa, p = 0.017) placentas were found to be significantly stiffer compared with the control placentas (8.32 ± 3.67 kPa). A linear discriminant analysis (LDA) classifier was able to classify between healthy and diseased placentas with a sensitivity, specificity and accuracy of 87%, 78% and 83% and an area under the receiver operating curve of 0.90 (95% confidence interval: 0.8-0.99). Further, the pregnancy outcome in terms of neonatal intensive care unit admission was predicted with a sensitivity, specificity and accuracy of 70%, 71%, 71%, respectively, and area under the receiver operating curve of 0.78 (confidence interval: 0.62-0.93). A viscoelastic characterization of placentas using a fractional rheological model revealed that the viscosity measures in terms of viscosity parameter n were significantly higher in IUGR (2.3 ± 0.21) and PE (2.11 ± 0.52) placentas than in normal placentas (1.45 ± 0.65). This work illustrates the potential relevance of elasticity and viscosity imaging using SWAVE 2.0 as a non-invasive technology for detection of placental abnormalities and the prediction of pregnancy outcomes.

Morbidly Adherent Placenta in the First Trimester with Consecutive Hysterectomy.

Background Morbidly adherent placenta (MAP) represents a risk factor for a maternal adverse outcome and its incidence continues to rise following the increasing rate of caesarean deliveries. The detection of a pathology of placental adherence in the first trimester is challenging. Transvaginal ultrasound represents (TVUS) a reliable tool for accurate and timely diagnosis. Case We report on a case of MAP in a pregnant woman at 10 weeks of gestation with two prior caesarean deliveries. She presented with abdominal pain and hematometra. The first trimester diagnosis was made with TVUS and confirmed with magnetic resonance imaging. The patient required an urgent hysterectomy. Conclusion Antenatal care in the first trimester in women with a previous cesarean delivery should include a detailed examination of the placenta with TVUS.

Ultrasound and MRI appearance of abnormally adherent placenta in a woman with Asherman's syndrome.

Although 10% of pregnancies following treatment of Asherman's syndrome are estimated to have abnormal placental adhesion, there is a paucity of reports describing imaging features in such cases. We describe ultrasound and MRI features in one of such cases, showing a peculiar pattern of shallow but diffuse abnormally adherent placenta.

Interstitial Laser Ablation of Feeding Vessels to a Large Placental Chorioangioma.

BACKGROUND: Chorioangioma is a vascular neoplasm of the placenta with the potential to cause heart failure, hydrops, and even death. CASE: A 30-year-old patient was referred owing to a large placental chorioangioma and fetal hydrops at 28 weeks of gestation. The patient underwent ultrasound-guided interstitial laser ablation. Ten days later, fetal blood transfusion was performed and at 31 weeks of gestation, and the patient delivered a female infant by cesarean section. The newborn was discharged from the neonatal intensive care unit without any complication. CONCLUSION: According to our case, large placental chorioangioma may have a favorable outcome with interstitial laser ablation and fetal transfusion.

Management of a rare case of placenta trophotropism.

There are several variations of placental shape or implantation. Multilobed placentas are thought to arise due to implantation in areas of decreased uterine perfusion. An example is represented by lateral implantation in between the anterior and posterior walls of the uterus. Other local factors leading to multilobation are implantation over leiomyomas, in areas of previous surgery, in the cornu, or over the cervical os. After implantation, there is preferential growth in areas of superior perfusion and atrophy in areas of poor perfusion. This is called trophotropism. We described a singular case of uterine synechia, where is laid the succenturiate lobe from the anterior to the posterior wall, obstacles fetal head descent in the pelvis. Due of that synechia, a cesarean section is necessary for fetal transverse situation with reverse breech extraction.

T2*-weighted placental magnetic resonance imaging: a biomarker of placental dysfunction in small-for-gestational-age pregnancies.

BACKGROUND: The antenatal identification of placental dysfunction in small-for-gestational-age fetuses with normal fetal Doppler flows remains an obstetrical challenge. In a significant fraction of such pregnancies, placental dysfunction is revealed by clinical manifestations such as preeclampsia, preterm delivery, or severe small-for-gestational-age at birth or by abnormal findings in the postnatal placental histologic examination. Therefore, new methods to identify placental function directly in pregnancy at the time of small-for-gestational-age diagnosis is highly needed. T2*-weighted placental magnetic resonance imaging is sensitive to changes in placental morphology and oxygenation and is thereby related to placental function. Previous studies have demonstrated that pregnancies complicated by low birthweight and preeclampsia are characterized by low placental T2* values. However, the specific performance of placental T2* in the prediction of placenta-related outcomes in small-for-gestational-age pregnancies with normal fetal Doppler flows remains to be explored. OBJECTIVE: In small-for-gestational-age pregnancies with normal fetal Doppler flows, we aimed to evaluate T2*-weighted placental magnetic resonance imaging as an antenatal biomarker of placental dysfunction. In addition, we aimed to investigate the correlation between placental T2* and Doppler flow measurements of fetal and uterine arteries at the time of magnetic resonance imaging. STUDY DESIGN: In this prospective cohort study, the inclusion criterion was suspected small-for-gestational-age (ultrasound estimated fetal weight Z-score ≤-2.0 [2.3rd centile]) with normal fetal Doppler flows (middle cerebral artery pulsatility index Z-score > -2.0 and umbilical artery pulsatility index Z-score <2.0). The T2*-weighted placental magnetic resonance imaging scan was performed at inclusion in a 1.5 T system. The outcomes was placental dysfunction at birth defined by low birthweight (Z-score ≤-2.0), preeclampsia, preterm delivery (gestational age<37 weeks), or abnormal placental histologic examination such as placental vascular malperfusion according to the Amsterdam Consensus Statement. RESULTS: We included 92 pregnancies at 26+5 to 39+6 weeks gestation. The median time interval between the magnetic resonance imaging scan and birth was 4.6 weeks (interquartile range, 2.7-7.8 weeks). At birth, 55% (51/92) of pregnancies revealed at least 1 sign of placental dysfunction; 49% (40/81) had abnormal placental histologic examination, 29% (27/92) were born with low birthweight, 13% (12/92) were delivered preterm, and 7% (6/92) had preeclampsia. When adjusted for gestational age at magnetic resonance imaging, the placental T2* Z-score was a significant predictor of abnormal placental histologic examination (area under the curve, 0.73; P=.001), small-for-gestational-age at birth (area under the curve, 0.63; P=.030), preeclampsia (area under the curve, 0.88; P=.005), and preterm delivery (area under the curve, 0.81; P=.001). The placental T2* was reduced in pregnancies with a combination of clinical manifestations and abnormal placental histologic examination (T2* Z-score=-1.52±1.35 [mean±standard deviation]; P=.0001) and in clinically uneventful pregnancies with abnormal placental histologic examination (T2* Z-score=-0.79±0.97; P=.045). At the time of magnetic resonance imaging, the placental T2* Z-score showed a significant linear correlation with the uterine artery pulsatility index Z-scores (r=-0.24; P=.016) and the middle cerebral artery pulsatility index Z-scores (r=0.29; P=.017) but not with the umbilical artery pulsatility index Z-scores (r=0.18; P=.17) and the cerebroplacental ratio (r=0.03; P=.77). CONCLUSION: This study indicates that placental dysfunction is frequent in small-for-gestational-age fetuses with normal fetal Doppler flows. In this cohort, T2*-weighted placental magnetic resonance imaging is a sensitive biomarker of placental dysfunction regardless of the clinical manifestations. This finding supports a paradigm shift in the conception of placental dysfunction that may cover a wide spectrum of clinical and subclinical manifestations.

Perfusion fraction derived from IVIM analysis of diffusion-weighted MRI in the assessment of placental vascular malperfusion antenatally.

INTRODUCTION: Specific placental pathologies that may impact fetal development, such as vascular malperfusion, are diagnosed postpartum. We aimed to evaluate if placental perfusion fraction (f) derived from intravoxel incoherent motion (IVIM) analysis of diffusion-weighted magnetic resonance imaging (DWI) can be used to identify specific types of placental vascular malperfusion antenatally. METHOD: 93 women who underwent placental DWI with multiple b-values at 23.9-41.3 week's gestation and postpartum histological examination were identified in the local placental MRI research database. Based on the placental examination, 44 were defined as normal controls and 49 cases had placental vascular malperfusion. Vascular malperfusion was subdivided into fetal vascular malperfusion (n = 13), maternal vascular malperfusion (n = 30) or both (n = 6). For each placenta, regions of interest were drawn on three placental slices and their mean f was estimated using intravoxel incoherence motion analysis. RESULTS: In normal placentas mean f was 26.0 ± 4.6% (mean ± SD) and no linear correlation between f and gestational age was found, r = -0.05, p = 0.72. Placentas with fetal vascular malperfusion showed a significantly lower f (22.7 ± 4.4%) compared to normal controls, p = 0.03. In cases of maternal vascular malperfusion (25.2 ± 6.4%), no significant difference in f was revealed, p = 0.55. CONCLUSIONS: These results indicate that placental DWI-derived f may identify fetal vascular malperfusion in vivo. This study confirms a previous pilot study and provides initial evidence that fetal and maternal vascular malperfusion have different MRI signatures. Future studies are needed to further explore the clinical significance of this interesting finding.

Novel ultrasound assessment of placental pathological function using superb microvascular imaging.

Ultrasound Doppler method of Superb Microvascular Imaging (SMI) can significantly visualize low-velocity blood flow using a unique algorithm. We scanned placenta antenatally using SMI and compared those findings with histological findings after delivery in cases with placental abnormalities. In normal, SMI expresses stem villous vessels connecting to the tertiary villous vessels which are sharply diminished, and expresses intervillous blood flow as "scatter." Placental infarction was expressed as an anechoic area in SMI. Avascular villi was expressed as absent villous blood trees in a background scatter flow in SMI. In this report, we demonstrated typical SMI findings of the pathologic placenta as a pilot study.