Assessment of alterations in the electrical impedance of muscle after experimental nerve injury via finite-element analysis.
IEEE Trans Biomed Eng
; 58(6): 1585-91, 2011 Jun.
Article
em En
| MEDLINE
| ID: mdl-21224171
The surface measurement of electrical impedance of muscle, incorporated as the technique of electrical impedance myography (EIM), provides a noninvasive approach for evaluating neuromuscular diseases, including amyotrophic lateral sclerosis. However, the relationship between alterations in surface impedance and the electrical properties of muscle remains uncertain. In order to investigate this further, a group of healthy adult rats, a group of rats two weeks postsciatic crush, and a group of animals six months postcrush underwent EIM of the gastrocnemius-soleus complex. The animals were then killed and the conductivity and permittivity of the extracted muscle measured. Finite-element models based on MRI data were then constructed for each group. The characteristic EIM parameter, 50 kHz phase (±standard error), obtained with surface impedance measurements was 17.3° ± 0.3° for normal animals, 13.8° ± 0.7° for acutely injured animals, and 16.1° ± 0.5° for chronically injured animals. The models predicted parallel changes with phase values of 24.3°, 18.8°, and 21.2° for the normal, acute, and chronic groups, respectively. Other multifrequency impedance parameters showed similar alterations. These results confirm that surface impedance measurements taken in conjunction with anatomical data and finite-element models may offer a noninvasive approach for assessing biophysical alterations in muscle in neuromuscular disease states.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Nervo Isquiático
/
Impedância Elétrica
/
Músculo Esquelético
/
Análise de Elementos Finitos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
IEEE Trans Biomed Eng
Ano de publicação:
2011
Tipo de documento:
Article