Hair-on-end appearance is associated with all of the following except: March 2010, September 2010

Ans. C: Aplastic Anemia Hair-on-end skull: Thin fine linear extensions radiating out from the skull that look on an X-ray like hair standing "on-end" from the skull, an appearance associated with hemolytic anemias such as: Sickle cell disease Thalassemia G-6-PD Deficiency Hereditary spherocytosis Elliptocytosis Pyruvate kinase deficiency. The "hair" represents the accentuated trabeculae extending between the inner and outer skull tables through the diploe in the expanded bone marrow space (because the bone marrow has expanded due to the excessive breakdown of red blood cells). The "hair" appears to be "on end" because the trabeculae are oriented perpendicular to the inner and outer tables of the skull.