Figure 6. (a) Plain radiograph showing partial absence of the right sacrum and coccyx (arrow) in a patient with an anterior meningocele. (b) Sagittal spinal ultrasound (same patient) demonstrates an anechoic unilocular meningocele anterior to the sacrum (long arrow), anterior to the inferior portion of the sacrum (short arrow). (c)Sagittal T₁ weighted MRI (same patient) demonstrates a low signal meningocele (arrow) anterior to the inferior portion of the sacrum.