Spina Bifida Ultrasound Signs Explained

Spina bifida is a neural tube defect affecting the spinal cord. Ultrasound plays a crucial role in its prenatal diagnosis.

Key Ultrasound Findings in Spina Bifida

Several specific signs can be observed on fetal ultrasound when Spina bifida is present:

• Vertebral Defect: The primary sign is the visualization of a defect in the vertebral bodies, often with associated protrusion or absence of the overlying skin and neural tissue (meningocele or myelomeningocele).
• Lemon Sign: This sign refers to the characteristic inward scalloping of the frontal bones of the fetal skull, giving it a lemon-like shape. It is often associated with the Chiari II malformation, which frequently accompanies myelomeningocele.
• Banana Sign: This sign describes the appearance of the cerebellum in the posterior fossa during ultrasound. In cases of Chiari II malformation, the cerebellum is often elongated and curved around the brainstem, resembling a banana shape.

Conclusion

Since the direct vertebral defect, the Lemon sign, and the Banana sign are all potential ultrasound findings in fetuses diagnosed with Spina bifida (often due to the associated Chiari II malformation), the option encompassing all these signs is the correct choice.

Therefore, all the mentioned signs may be seen on ultrasound in a fetus with Spina bifida.