抄録
Recently the interest in the early diagnosis or care for the acoustic tumor has been increasing and new ways to diagnose or to koperate are being devised. We report here a experience in which we could entirely remove the acoustic tumor found comparably earlier through the translabyrinthine approach. The case was a 21-years-old man whose chief complaints were vertigo, left ear deafness and left facial paresis. The hearing test showed entirely deaf on the left ear; the vestibular examination showed right gaze nystagmus and positional nystagmus to the right; Mann's test was positive; stepping test showed remarkable unsteadiness; the left ear had no reaction on the caloric test and a dead labyrinth of the left ear was observed clinically. Also the expansion of the left internal auditory meatus was found through Stenvers and Towne roentgenographing.
From those views we diagnose him as a left acoustic tumor and performed the suboccipital craniotomy. As the result of the operation, the tumor could not be found at the cerebellopontine angle and we tried to magnify the internal auditory meatus in vain, so we only collect the biopsy from the meatus. During the operation the facial nerve was damaged. As the tumor was supposed to be found only in the internal auditory meatus, we determined to perform the removal of the acoustic tumor through the translabyrinthine approach. We incised the postauricle and the mastoid cavity, exposed the facial nerve, opened the horizontal, posterior and anterior semicircular canal, removed the cochlea, and reached the internal auditory meatus. On incision of the dura of the meatus, the yellow-white tumor, which was covered with a thin capsule and was as large as a red bean, was found. We removed it with a forceps under operating microscope, set a gelfoam in the internal auditory meatus, filled the mastoid cavity with the pedicle temporal muscle flap, and primary stitched up the postauricle. The result of the histopathological examination of the tumor proved to be neuro-fibroma.
The patient has been favorably well, 10 months after the operation.
