Thoraco-omphalopagus conjoined twins: comprehensive evaluation with sonography and MRI in first trimester—a rare imaging diagnosis

Conjoined twins, or Siamese twins as they are commonly called, are a rare and extreme form of monochorionic twinning. Imaging plays an essential role in the diagnosis and follow-up of conjoined twins. While ultrasound is often the screening modality of choice, MRI is carried out for better anatomical delineation and further characterization as and when necessary. We present a unique case of first trimester thoraco-omphalopagus conjoined twins with cystic hygroma who were comprehensively evaluated with sonography and MRI with imaging findings confirmed post-pregnancy termination. The case stresses upon the utility of advanced imaging techniques including foetal MRI that immensely contribute towards a reliable diagnosis.