The Contrast None is identified by letter "Z" and occupies the 5th position in the ICD10-PCS procedure code structure.
Below a selection of ICD 10 PCS codes related to BY34Z
MRI of Fetal Spine using Oth Contrast
Magnetic Resonance Imaging (MRI) of Fetal Spine
MRI of Fetal Spine using Oth Contrast, Unenh, Enhance