This is not a " cobra deformity" . You have some swelling and irregularity in the submental/ submandibular area ( right greater then left ) . I can also see your submandibular gland which can become more obvious after facial surgery . Has any steroid injection been tried ? I would try steroid and if it has not helped you can consider revision surgery in the next few months . ( if you are not a smoker you could do sooner then later ) . Although not an ideal result if you had a very "full" neck prior to surgery this can happen and I would discuss with your present surgeon .Thanks
