Diagnostic accuracy of routine anomaly scans in identifying congenital malformations during the second trimester. A cross-sectional observational study.

Chhani Lal Narsingh  Sidar; Vidya  Laxmi

doi:10.51168/sjhrafrica.v6i9.2069

Authors

Chhani Lal Narsingh Sidar Associate Professor, Department of Radiodiagnosis, Abhishek I. Mishra Memorial Medical College and Research, Junvani, Durg, District Durg, Chhattisgarh, India
Dr. Vidya Laxmi Tutor, Department of Radiodiagnosis, Abhishek I. Mishra Memorial Medical College and Research, Junvani, Durg, District Durg, Chhattisgarh, India.

DOI:

https://doi.org/10.51168/sjhrafrica.v6i9.2069

Keywords:

Congenital malformations, anomaly scan, diagnostic accuracy, prenatal screening, second trimester

Abstract

Background:
Congenital malformations remain a leading cause of neonatal morbidity and mortality worldwide. Early detection through routine anomaly scans during the second trimester is critical for timely counseling, management, and improving pregnancy outcomes. However, the diagnostic accuracy of these scans varies depending on the type of anomaly and the expertise of the examiner.

Objective:

To evaluate the diagnostic accuracy of routine second-trimester anomaly scans in detecting congenital malformations when compared with postnatal findings.

Methods:

A cross-sectional observational study was conducted among 100 pregnant women undergoing routine anomaly scans between 18 and 22 weeks of gestation. Findings were compared with postnatal examinations and confirmatory investigations. Sensitivity, specificity, predictive values, and overall diagnostic accuracy were calculated.

Results:

Out of 100 cases, routine anomaly scans detected congenital malformations in 18 fetuses (18%). Postnatal evaluation confirmed 20 malformations, including 16 true positives, 2 false positives, and 4 false negatives. Sensitivity was 80%, specificity 97.6%, positive predictive value 88.9%, negative predictive value 95.2%, and overall diagnostic accuracy 94%. Central nervous system anomalies were most common (6%), followed by cardiac (6%), skeletal (5%), renal (3%), and gastrointestinal anomalies (2%). Missed anomalies were primarily subtle cardiac and skeletal malformations.

Conclusion:

Routine second-trimester anomaly scans demonstrate high diagnostic accuracy, particularly for central nervous system and renal malformations. However, cardiac and skeletal anomalies remain challenging and require meticulous evaluation.

Recommendations:

Enhanced operator training, incorporation of advanced imaging techniques, and standardized protocols are recommended to improve detection rates of cardiac and skeletal anomalies during routine anomaly scans.

Author Biographies

Chhani Lal Narsingh Sidar, Associate Professor, Department of Radiodiagnosis, Abhishek I. Mishra Memorial Medical College and Research, Junvani, Durg, District Durg, Chhattisgarh, India

is currently serving as an Associate Professor in the Department of Radiodiagnosis at Abhishek I. Mishra Memorial Medical College & Research, Junvani, Durg, Chhattisgarh (India) since March 2024.

He completed his MBBS in 1992 from Gajra Raja Medical College, Gwalior (Madhya Pradesh) under Jiwaji University, and subsequently obtained his MD in Radiodiagnosis in 1998 from the same institution. Following his graduation, he worked as a Resident Medical Officer in the Radiology department at Pandit Jawaharlal Nehru Hospital and Research Centre, Bhilai, from July 1994 to April 1995.

Dr. Sidar has extensive teaching and clinical experience. He served as a Senior Resident from April 2017 to April 2018 and later worked as an Assistant Professor in Radiodiagnosis at Bharat Ratna Late Shri Atal Bihari Vajpayee Memorial Medical College, Rajnandgaon, Chhattisgarh, from February 2019 to March 2024.

With over two decades of clinical exposure and academic involvement, Dr. Sidar has contributed significantly to radiodiagnostic education and patient care. His areas of expertise include diagnostic imaging, ultrasound, and cross-sectional radiology. He is actively engaged in undergraduate and postgraduate teaching and continues to serve as a guide and mentor for medical students. ORCID ID:https://orcid.org/0009-0009-5508-1112

Dr. Vidya Laxmi, Tutor, Department of Radiodiagnosis, Abhishek I. Mishra Memorial Medical College and Research, Junvani, Durg, District Durg, Chhattisgarh, India.

is working as a Tutor in the Department of Radiodiagnosis at Abhishek I. Mishra Memorial Medical College & Research, Junvani, Durg, Chhattisgarh, India. She is actively involved in academic teaching and clinical radiology, with a special interest in diagnostic imaging and ultrasound.

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