a low cost camera and radio frequency transmitter are coupled to an endotracheal tube to obtain an image in real time of tissue at the distal end of the endotracheal tube . the image recorded by the camera is transmitted to a low cost radio frequency receiver nearby and conveyed to a video monitor to display the image . the use of a wireless transmission system avoids the presence of wires and cords that otherwise might become entangled and cause the endotracheal tube to be inadvertently repositioned or pulled out of the patient .