Section 874.3930 - Tympanostomy tube with semipermeable membrane(a)Identification. A tympanostomy tube with a semipermeable membrane is a device intended to be implanted for ventilation or drainage of the middle ear and for preventing fluids from entering the middle ear cavity. The device is inserted through the tympanic membrane to permit a free exchange of air between the outer ear and middle ear. The tube portion of the device is made of silicone elastomer or porous polyethylene, and the membrane portion is made of polytetrafluoroethylene.(b)Classification. Class II. The special control for this device is FDA's "Tympanostomy Tubes, Submission Guidance for a 510(k)."51 FR 40389, Nov. 6, 1986, as amended at 65 FR 17145 , Mar. 31, 2000