The ruling on a patient whom the doctor has prevented from prostrating

Question:
Some patients, when they have had an operation on their eyes and the doctor prevents them from prostrating, are observed to pray while sitting, and some may perform dry ablution?

Answer:
He prostrates in the air. If he is prevented from prostrating, he lowers his head more than in bowing, but does not prostrate. If he has a bandage on, he wipes over it. He washes his face and wipes over the bandage.
Q: But his prayer is while sitting?
The Shaykh: No, that is not permissible. He must stand, unless he is ill.