Diagnostic accuracy of ultrasound versus MRI in the evaluation of placenta previa and its variants: A multicentric retrospective cross-sectional study.

Meenal  Chugh; Kalpana  Chugh; Vismandeep Kaur  Sandhu

doi:10.51168/sjhrafrica.v6i12.2237

Authors

Meenal Chugh Assistant Professor, Department of Obestetrics and Gynaecology, RNT Medical College, Udaipur, Rajasthan, India
Kalpana Chugh Senior Consultant, Department of Obstetrics and Gynaecology, Kalpana Nursing Home, Udaipur, Rajasthan, India
Vismandeep Kaur Sandhu Junior Resident, Department of Obstetrics and Gynaecology, Kalpana Nursing Home, Udaipur, Rajasthan, India

DOI:

https://doi.org/10.51168/sjhrafrica.v6i12.2237

Keywords:

Placenta previa, Ultrasound, Placenta previa variants, Magnetic resonance imaging (MRI)

Abstract

Background

Placenta previa is a major cause of maternal morbidity. Ultrasound (US) is first-line, but MRI is often used when findings are equivocal or high-risk features are present.

Objective: To compare the diagnostic accuracy of US and MRI in detecting placenta previa and classifying its variants.

Methods

A retrospective study was conducted over 18 months at two tertiary centers (Narayan Medical College & Hospital, Jamuhar, and RNT Medical College, Udaipur). A total of 120 women who underwent both obstetric US and MRI during pregnancy and subsequently delivered at either center were included. Delivery findings were taken as the reference standard.

Results

Placenta previa was confirmed in 48/120 (40%) women. US achieved sensitivity 87.5%, specificity 90.3%, PPV 85.7%, NPV 91.5%, and accuracy 89.2%. MRI demonstrated sensitivity 93.8%, specificity 91.7%, a PPV 88.2%, NPV 95.7%, and accuracy 92.5%. McNemar’s test showed no statistically significant difference between modalities. MRI demonstrated higher concordance in classifying variants (85% vs 75% for US; weighted κ 0.82 vs 0.72). Interobserver agreement was good for both modalities (US κ=0.78; MRI κ=0.83).

Conclusion

Both US and MRI showed high accuracy for placenta previa. MRI provided modestly superior sensitivity and variant classification, especially in posterior placenta and prior cesarean cases.

Recommendation

MRI should be used selectively in cases with posterior placenta, prior cesarean section, or inconclusive ultrasound findings to improve diagnostic confidence and surgical planning.

Author Biography

Kalpana Chugh, Senior Consultant, Department of Obstetrics and Gynaecology, Kalpana Nursing Home, Udaipur, Rajasthan, India

Senior Consultant, Department Of Obstetrics And Gynaecology, Kalpana Nursing Home , Udaipur , Rajasthan, India

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