Any such examination may be made by a physician or institution designated by the board, in which case the cost thereof and of all laboratory tests and fluoroscopic or X-ray procedures shall be borne by the board or, at the option of the employee, they may be made by a physician or institution of his own choosing, approved by the board, in which case said examination shall be made at the employee's expense.
N.J.S. § 18A:16-3