Facial nerve herniation.A 61-year-old man presented to the office with a 3-month history of right-sided hearing loss that caused him difficulty in his normal environment. He denied any history of associated illness, including otitis media. He had no complaints of dizziness or disequilibrium linkage disequilibrium the occurrence in a population of two linked alleles at a frequency higher or lower than expected on the basis of the gene frequencies of the individual genes. dis·e·qui·lib·ri·um (d  s-. Microscopic examination of the right ear revealed an atrophic atrophic /atro·phic/ (a-tro´fik) pertaining to or characterized by atrophy. collapse of the posterior tympanic membrane with retraction under the malleus and adherence to an eroded incus and stapes capitulum ca·pit·u·la (-l  ) A small head or rounded articular extremity of a bone. ca·pit . A perforation with associated granulation  u·lar adj.1. the division of a hard substance into small particles. 2. the formation in wounds of small, rounded masses of tissue during healing; also the mass so formed. arachnoidal granulations , cerebral granulations enlarged arachnoid villi projecting into the venous sinuses and creating slight depressions on the surface of the cranium. tissue was noted inferiorly. The appearance of the left ear was normal, without significant retraction or effusion 1. escape of a fluid into a part; exudation or transudation. 2. effused material; an exudate or transudate. pleural effusion fluid in the pleural space. ef·fu·sion . No mass or lesion was seen on nasopharyngoscopy. An audiogram au·di·o·gram (ô d --gr m demonstrated a mild conductive hearing loss in the right ear. The speech discrimination scores in both ears were identical (96%), the speech reception threshold on the right was 30 dB, and the pure-tone average was 30 dB. In view of the depth of the retraction pocket under the malleus, high-resolution computed tomography (CT) was ordered to look for the presence of a cholesteatoma cho·les·te·a·to·mas or cho·les·te·a·to·ma·ta (-m -t) A tumorlike mass of keratinizing squamous epithelium and cholesterol, usually occurring in the middle ear and mastoid region. . CT demonstrated a large retraction pocket with erosion of the incus and soft-tissue attenuation between the tympanic portion of the right facial nerve and the incudostapedial incudostapedial /in·cu·do·sta·pe·di·al/ (-stah-pe´de-il) pertaining to the incus and stapes.in·cu·do·sta·pe·di·al ( ng articulation. The patient underwent a right tympanoplasty and middle ear exploration via a postauricular approach with continuous facial nerve monitoring. A 2 x 2-mm mucosa-like mass was encountered in the region of the tympanic segment of the facial nerve superior to the stapes (figure). The mass stimulated at 0.1 mA and activated both the upper and lower divisions of the facial nerve, as evidenced by the tracings on the facial nerve monitor. The tympanoplasty was completed without further manipulation of the mass. No postoperative facial weakness was demonstrated. Postoperative magnetic resonance imaging demonstrated no enhancement of the tympanic course of the facial nerve and no evidence of facial nerve neuroma. The intraoperative findings were consistent with facial nerve herniation herniation of intervertebral disk herniated disk; protrusion of the nucleus pulposus or anulus fibrosus of the disk, which may impinge on nerve roots. herniation of nucleus pulposus see h. of intervertebral disk. tentorial herniation . Nathan Hales, MD; Wayne Berryhill, MD |
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