Die Bedeutung der Elektrodiagnostik in der Kleintiermedizin - eine retrospektive Analyse

In a retrospective study including the records of 628 patients of
the Medizinische Kleintierklinik München, the significance of
electromyography (EMG), electroneurography (ENG) and auditory
evoked potentials (AEP) for the clinical diagnosis was determined.
Indications for AEP examination were screening for hereditary
deafness (59.5%), evaluation of hearing abilities for other reasons
(19.2%), vestibular syndrome (13.4%), suspicion on brainstem
disease (2.3%), suspicion on hereditary ataxia in the Jack Russell
terrier (1.8%) and facial paralysis (3.8%). Indication for the
EMG/ENG examination were exclusion of (4.0%) or suspicion on
(10.1%) lumbosacral syndrome, lameness of unknown origin (23.5%),
paraparesis (8.7%) and tetraparesis (3.4%) of unknown origin,
clinical suspicion on a focal neuropathy (15.1%), on a generalized
neuromuscular disorder (30.5%), or on masticatory myositis (3.4%),
and miscellaneous (1.3%). The electrodiagnostic examination was of
decisive significance for the diagnosis of the following diseases:
congenital deafness, acquired deafness, focal neuropathies. The
electrodiagnostic examination was mostly not decisive, but
characterized the disease and indicated the final clinical
diagnosis in following indications: (1) AEP for vestibular
syndrome, suspicion on brainstem disease, hereditary ataxia of the
Jack Russell terrier and facial paresis. (2) EMG and ENG for
lameness of unkown origin, suspicion on lumbosacral syndrome,
suspicion on a generalized neuromuscular disorder, suspicion on
masticatory myositis. For some neuromuscular diseases, sensitivity
(S%) and positive predictive value (PPV%) of the electrodiagnostic
examination were established: In lumbosacral syndrome, S% was 87.5%
and PPV% was 66.7%. In focal neuropathy, S% was 98.3% and PPV% was
100%. In generalized neuromuscular disorders, S% was 91.6% and PPV%
was 85.3%; within this group, polymyopathies were diagnosed with S%
= 63.6%, polyneuropathies with S% = 90.9%, and neuro-muscular
transmission disorders with S% = 75 %. Thus, multiple indications
were shown, in which the electrodiagnostic examination contributed
essentially to the clinical diagnosis.