Assessment of postpartum haemorrhage for placenta accreta: Is measurement of myometrium thickness and dark intraplacental bands using MRI helpful?

BACKGROUND: This study aimed to investigate the predictive values of magnetic resonance imaging (MRI) myometrial thickness grading and dark intraplacental band (DIB) volumetry for blood loss in patients with placenta accreta spectrum (PAS). METHODS: Images and clinical data were acquired from patients who underwent placenta MRI examinations and were diagnosed with PAS from March 2015 to January 2021. Two radiologists jointly diagnosed, processed, and analysed the MR images of each patient. The analysis included MRI-based determination of placental attachment, as well as myometrial thickness grading and DIB volumetry. The patients included in the study were divided into three groups according to the estimated blood loss volume: in the general blood loss (GBL) group, the estimated blood loss volume was < 1000 ml; in the massive blood loss (MBL) group, the estimated blood loss volume was ≥ 1000 ml and < 2000 ml; and in the extremely massive blood loss (ex-MBL) group, the estimated blood loss volume was ≥ 2000 ml. The categorical, normally distributed, and non-normally distributed data were respectively analysed by the Chi-square, single-factor analysis of variance, and Kruskal-Wallis tests, respectively. The verification of correlation was completed by Spearman correlation analysis. The evaluation capabilities of indicators were assessed using receiver operating characteristic curves. RESULTS: Among 75 patients, 25 were included in the GBL group, 26 in the MBL group, and 24 in the ex-MBL group. A significant negative correlation was observed between the grade of myometrial thickness and the estimated blood loss (P < 0.001, ρ = - 0.604). There was a significant positive correlation between the volume of the DIB and the estimated blood loss (P < 0.001, ρ = 0.653). The areas under the receiver operating characteristic curve of the two MRI features for predicting blood loss ≥ 2000 ml were 0.776 and 0.897, respectively. CONCLUSIONS: The grading and volumetric MRI features, myometrial thickness, and volume of DIB, can be used as good prediction indicators of the risk of postpartum haemorrhage in patients with PAS.

Postpartum ultrasound: postpartum assessment using ultrasonography.

Postpartum haemorrhage (PPH) is a potential cause of maternal mortality, and obstetricians must be prepared to rapidly diagnose and treat this condition. Optimal treatment is dependent upon the underlying cause of haemorrhage. Ultrasonography is the most helpful tool for prompt diagnosis of PPH aetiology and obstetricians must have a strong understanding of postpartum ultrasonography. In our previous report, we demonstrated the utility of ultrasonography using the focused assessment with sonography for obstetrics (FASO) technique (a modified version of FAST) as the primary postpartum obstetric survey. In the present article, we review the ultrasonographic findings of PPH, differentiated by the underlying cause of haemorrhage, including retained placenta, morbidly adherent placenta, uterine rupture, uterine inversion and uterine artery abnormalities.

Transvaginal ultrasound and sonohysterography for assessment of postpartum residual trophoblastic tissue.

OBJECTIVE: To compare the accuracy of transvaginal ultrasound and sonohysterography (SHG) in diagnosing residual trophoblastic tissue in postpartum women and to assess the adverse effects and complications of the SHG procedure. METHODS: A prospective study of patients with postpartum bleeding enrolled for clinical symptoms and signs of residual trophoblastic tissue. All women underwent transvaginal ultrasound and SHG. Uterine cavity curettage was performed in all women and the material collected was sent for pathologic examination. RESULTS: Among 84 patients, transvaginal ultrasound revealed residual trophoblastic tissue in 60 women, whereas SHG detected residual trophoblastic tissue in 48 and blood clots in 12. Pathologic examination confirmed trophoblastic tissue in 48 patients and blood clots in 12. Fifteen (17.9%) patients experienced adverse effects after SHG. Thirteen (15.5%) experienced postprocedural fever that resolved with antibiotics. Two women (2.4%) had severe complications of infection: 1 required surgery for peritonitis, which revealed salpingitis and a pelvic abscess; 1 experienced fever and mild abdominal pain that resolved with antibiotics after 10 days of hospitalization. CONCLUSIONS: Although SHG showed greater accuracy than transvaginal ultrasound in detecting residual trophoblastic tissue, a high proportion of patients experienced adverse effects.

A comparison of clinical assessment with ultrasound in the management of secondary postpartum haemorrhage.

OBJECTIVE: To compare the diagnostic accuracy of clinical assessment with transabdominal ultrasound in the management of secondary postpartum haemorrhage (PPH). DESIGN: A prospective cohort study. METHODS: Fifty-three women who presented to a teaching hospital obstetric unit with secondary PPH were studied. Patients were divided into those in whom retained placental tissue was or was not the suspected cause of bleeding. This diagnosis was based on history/examination and transabdominal pelvic ultrasound scan. The definitive diagnosis was made following uterine evacuation or was assumed in women who stopped bleeding without surgical management. Likelihood ratio (LR) was used as an accuracy measure. RESULTS: The positive LR for clinical assessment was 5.5 (95% CI 2.7-12.1) compared with 2.4 (95% CI 1.5-3.7) for ultrasound. The negative LRs were 0.1 (95% CI 0.04-0.5) and 0.1 (95% CI 0.02-0.5) for clinical and ultrasound assessment, respectively. CONCLUSION: Clinical examination and ultrasound scan assessment have limited diagnostic accuracy in secondary PPH.