title: Modified brain stem auditory evoked potentials in patients with intracranial mass lesions.
abstract: The authors report their experience utilizing a recently described rapid rate, binaural click and 1000-Hz tone burst modification of the brain stem auditory evoked potentials (BAEP), modified (MBP), in 27 symptomatic patients with non-brain stem compressive space-taking cerebral lesions (22), hydrocephalus (4), and pseudotumor cerebri (1).  Many presented with clinical signs suggestive of increased intracranial pressure (ICP) and focal neurological deficits. The cerebral lesions, mostly large tumors with edema, had very substantial radiological signs of mass effect. Fourteen patients were also studied following surgical decompression. A number of significant changes in the wave V and Vn latency/intensity and less so amplitude/intensity function was found in the 27 patients, compared to normal volunteers, as well as those studied pre- and postoperatively. Similar MBP changes had been noted in normal volunteers placed in a dependent head position. Possible mechanisms to explain these findings are discussed.  The MBP methodology shows promise and further development could make neuro-intensive care unit monitoring practical.
authors.affiliation: Department of Neurosurgery and Neurology, University of Illinois Medical Center at Chicago, IL 60612, USA. jlstone4@aol.com
authors.forename: James L
authors.initials: JL
authors.lastname: Stone
authors.forename: John
authors.initials: J
authors.lastname: Fino
authors.forename: Ketan
authors.initials: K
authors.lastname: Patel
authors.forename: Mateo
authors.initials: M
authors.lastname: Calderon-Arnulphi
authors.forename: Nichole
authors.initials: N
authors.lastname: Suss
authors.forename: John R
authors.initials: JR
authors.lastname: Hughes
mesh_terms: D000328:Adult; D001306:Auditory Pathways / Q000503:physiopathology; D001929:Brain Edema / Q000175:diagnosis / Q000503:physiopathology; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000503:physiopathology*; D003422:Critical Care / Q000379:methods*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D005260:Female; D006801:Humans; D006849:Hydrocephalus / Q000175:diagnosis / Q000503:physiopathology; D007427:Intracranial Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods; D010865:Pilot Projects; D011559:Pseudotumor Cerebri / Q000175:diagnosis / Q000503:physiopathology; D011930:Reaction Time / Q000502:physiology