If the court finds the patient to be a drug user, it may commit him to a hospital designated by the patient or the Mayor and approved by the court, to be confined there for rehabilitation until released in accordance with § 24-709. In the event a patient elects to designate a hospital to which he wishes to be committed, he shall be required to satisfy the court that such hospital has medical, rehabilitation, and security facilities comparable to the institutions designated by the Mayor and, in addition, the cost of such hospitalization shall be borne by the patient. The head of the hospital shall submit written reports within such periods as the court may direct, but no longer than 6 months after the commitment and for successive intervals of time thereafter, and state reasons why the patient has not been released.