Brain Stem Auditory Evoked Potentials in Arnold-Chiari Malformation: Possible Prognostic Value and Changes with Surgical Decompression

Abstract

Symptomatic Arnold-Chiari malformation (Chiari II) is a recently described clinical entity, the natural history and surgical management of which remain controversial. The brain stem auditory evoked potentials (BAEPs) have been described as abnormal in 50 to 86% of children with myelomeningocele. We present the case of a full-term infant with myelomeningocele, shunted hydrocephalus, and Chiari II malformation who was surgically treated by decompression when she was 3 weeks old. BAEPs recorded immediately after decompression showed dramatic improvement over BAEPs recorded immediately before decompression, an improvement that could not be attributed to maturation of the central nervous system. It is postulated that in further large series the degree of abnormality in BAEPs may be of value in predicting the clinical course of these patients. The current status of BAEPs as they apply to the evaluation of posterior fossa anomalies is reviewed.

Natural Course of Brainstem Auditory Evoked Potentials in Infants Less Than 6 Months Old with Asymptomatic Meningomyelocele

“…Holliday et al [5] reported that there were abnormali ties in 50-86% of BAEPs in children with MMC. They also reported a patient with symptomatic Chiari II mal formation who underwent posterior fossa decompression (PFD) at 3 weeks of age.…”

“…BAEP recordings in patients with MMC, particularly with asymptomatic Chiari II malformation, have been made in older children [5,10,[17][18][19][20]26], On the other hand, it is well known that only 20% of children with MMC develop symptomatic Chiari II malformation and that in 65% of these patients this happens within the first 3 months of life [6,16]. Although this report is not only the first study on BAEPs in young patients with MMC, especially in infants less than 6 months old, there is very little systematic information on BAEPs in patients with Chiari II malformation during the first 6 months of life [11,16].…”

“…NS = Not significant. asymptomatic Chiari II malformations [5,7,[11][12][13][16][17][18][19][20][21]. Some articles have been published on the use of BAEPs in normal neonates and infants [20,[22][23][24], How ever, standard values of BAEPs for asymptomatic MMC are not necessarily available because the development of brainstem function in patients with MMC is thought to be delayed compared to normal neonates and infants.…”

Somatosensory and brainstem auditory evoked potential in congenital craniovertebral anomaly; effect of surgical management.

“…In recent years evoked potentials are routinely [12][13][14] This study is the only large prospective study of evoked potential in patients with congenital craniovertebral anomaly. This study shows a high incidence ( 10 patients, 31 %) of BAEP abnormality in patients of congenital atlantoaxial dislocation.…”

Brainstem Acoustic Evoked Responses: Maturational Aspects from Cochlea to Midbrain

“…Abnormalities ofwaveform and prolongation of interpeak latencies are objective indicators of brainstem involvement in various neuropediatric diseases, for example in post-asphyxiated children, dysraphic malformations or during neurointensive treatment (3,7,8,13,19 (4,10,11,14,15,17,20). For that reason, agedependent normative values are basically important for pediatric applications.…”