Document 0016
 DOCN  M9470016
 TI    Idiopathic, herpetic, and HIV-associated facial nerve palsies: abnormal
       MR enhancement patterns.
 DT    9409
 AU    Sartoretti-Schefer S; Wichmann W; Valavanis A; Department of
       Neuroradiology, University Hospital of Zurich,; Switzerland.
 SO    AJNR Am J Neuroradiol. 1994 Mar;15(3):479-85. Unique Identifier :
       AIDSLINE MED/94256300
 AB    PURPOSE: To determine specific criteria that can be used to define
       normal versus abnormal MR contrast enhancement of the facial nerve.
       METHODS: Twenty-three patients with acute unilateral inflammatory
       peripheral facial nerve palsy were examined on a 1.5-T MR using
       multiplanar T1-weighted spin-echo sequences before and after injection
       of gadopentetate dimeglumine. These MR patterns were compared with those
       of healthy control subjects. RESULTS: The normal facial nerve usually
       showed a mild to moderate enhancement of the geniculate ganglion and the
       tympanic-mastoid segment. The intracanalicular-labyrinthine segment did
       not enhance. All patients showed abnormal enhancement of the distal
       intracanalicular and the labyrinthine segment. An intense enhancement
       could be observed in the geniculate ganglion and the proximal tympanic
       segment, especially in herpetic palsy. Associated enhancement of the
       vestibulocochlear nerve was seen in herpetic and idiopathic palsy.
       Enhancement of the inner ear structures was detected only in herpetic
       palsy. CONCLUSIONS: Abnormal contrast enhancement of the distal
       intracanalicular and the labyrinthine facial nerve segment is observed
       in all patients and is the only diagnostically reliable MR feature
       proving an inflammatory facial nerve lesion. The intense enhancement of
       the geniculate ganglion and the proximal tympanic segment is possibly
       correlated with the reactivation of the latent infection in the sensory
       ganglion. The abnormal enhancement results from breakdown of the
       blood-peripheral nerve barrier and/or from venous congestion in the
       venous plexuses of the epi- and perineurium.
 DE    Acquired Immunodeficiency Syndrome/COMPLICATIONS  Adolescence  Adult
       Aged  Aged, 80 and over  Child  Facial Nerve/ANATOMY & HISTOLOGY  Facial
       Paralysis/ETIOLOGY/*PATHOLOGY  Female  Herpes Zoster Oticus/*PATHOLOGY
       Human  *Magnetic Resonance Imaging  Male  Middle Age  Prospective
       Studies  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).