<prompt> Hair on end appearance in X- ray is characteristic of:G6PD deficiencySickle cell anemiaRicketsScurvy  <response>: Ans. B. Sickle cell anemiaHair on end appearance of the skull is a characteristic feature of chronic Haemolysis usually seen in patients with thalassemia and sickle cell anaemia. It results from accentuated vertical trabeculae between the inner and outer tables of the skull because of excessive bone marrow hyperplasia. Conditions where Hair on End Appearance is seen:Mnemonic: HI NEST Hereditary spherocytosis Neuroblastoma Enzyme deficiency e.g. G-6-P deficiency causing haemolytic anaemia Sickle cell disease Thalassemia major 