I have been privileged to work with Dr. Esslen for more than ten years
and to have witnessed howsurgical progress combinedwith accurate
clinical and electrophysiological investigations have revolutionized the
diagnostic and therapeutic approach to the para- lysed face. The
longjourneyofthe VIIth nerve through the temporal bone has been consid-
ered for years responsible for the particular liabilityofthis nerve to
acute palsies. The disappointing results obtainedwith surgical
decompression confined ofnecessity to the mastoid and tympanic
segmentsofthe fallopian canalled us in the sixties to apply modern
otoneurosurgical techniques in orderto achieve total exposure ofthe
intra- temporal course ofthe facial nerve. At that time Esslen started
to record with surface electrodes the compound action potential evoked
by maximal percutaneous stimulation in representative areas ofthe facial
muscles. With this method, called electroneurono- graphy, exact
determination ot the percentageofdegenerated nerve fibers could be
achieved in the early stagesofthe palsy. Precise electroneuronographic
criteria for the selectionofpatients requiring surgery in order possibly
to improve the outcome oftheir disfiguring paralysis were worked out. At
surgery d ect stimulationofthe totally exposed intratemporal
portionofthe facial nerve was used for the first time in combina- tion
with electroneurography in order to determine objectively the degree
ofthe lesion. In contrast to what hasbeen believed for years the
pathology related with acute facial palsy has been found to be situated
in the majorityofthe cases at the entrance and not toward the exit ofthe
fallopian canal.