diff --git a/src/schema/rules/sidecars/mri.yaml b/src/schema/rules/sidecars/mri.yaml
index fbffa64e0d..e37dc0514b 100644
--- a/src/schema/rules/sidecars/mri.yaml
+++ b/src/schema/rules/sidecars/mri.yaml
@@ -36,6 +36,9 @@ MRIScannerHardware:
     MatrixCoilMode: recommended
     CoilCombinationMethod: recommended
     NumberTransmitCoilActiveElements: recommended
+    BodyPart: optional
+    BodyPartDetails: optional
+    BodyPartDetailsOntology: optional
 
 MRIScannerHardwareASL:
   selectors:
diff --git a/src/schema/rules/sidecars/pet.yaml b/src/schema/rules/sidecars/pet.yaml
index feb1db9053..aa942df8fd 100644
--- a/src/schema/rules/sidecars/pet.yaml
+++ b/src/schema/rules/sidecars/pet.yaml
@@ -28,6 +28,8 @@ PETScannerHardware:
     BodyPart:
       level: recommended
       description_addendum: Corresponds to DICOM Tag 0018, 0015 `Body Part Examined`.
+    BodyPartDetails: optional
+    BodyPartDetailsOntology: optional
 
 PETRadioChemistry:
   selectors: