| Namespace | MPheno.ontology | Obsolete | false |
| description | the presence of unusually thin or flattened red blood cells that when stained show a dark center and a peripheral ring of hemoglobin, separated by a pale unstained ring containing less hemoglobin, resulting in a bull's-eye appearance and resembling a 3D sombrero when viewed under EM; seen in certain anemias, thalassemias, hemoglobinopathies, obstructive jaundice, and the post-splenectomy state |
