The visualized paranasal sinuses are clear. IMPRESSION: Study is notable for irregular, stenotic bony portion of the right external auditory canal, and complete atresia of left external auditory canal as described above. Normal tympanic membranes is not seen on the right and is absent on the left, and the left malleus is abnormal in morphology and orientation. The mastoid portion of the left 7th cranial nerve is more anterior than normal. END OF IMPRESSION: 70480 RIGHT MICROTIA/LEFT CANAL ATRESIA CT HEAD UNENHANCED CT of the temporal bones was performed with thin cuts in both the axial and coronal planes.