<prompt> Hair on end appearance is characteristically seen inThalasemia majorSickle cell anaemiaG 6PD deficiencyHereditary spherocytosis  <response>: Ans. a Thalassemia major Ref. Radiology Review Manual, 5thpg.174Causes of hair on end or crew hair cut skull are Thalassemia Characteristic Hereditary spherocytosis Sickle cell disease G-6-PD deficiency Iron deficiency anaemia Neuroblastoma 