Is it permissible to perform ghusl (ritual bathing) from janabah (state of ritual impurity) without washing the head with water due to a surgical operation on the right ear and the doctor's prohibition of washing the head for 12 days?

If you are able to wash your head without water entering your ear, then you are required to wash it. However, if you are unable to do so, or if washing your head would harm your health, then you must wash the rest of your body and perform tayammum for the part you did not wash. This is the view of Shafi'i and Ahmad. Abu Hanifa and Malik, on the other hand, hold that if most of the body is sound, it should be washed, and no tayammum is required. But if most of it is injured, tayammum is performed, and no ghusl is required for it.