Table 2.
GBS Electrophysiologic Criteria
| Percent conduction velocity slowing |
Percent distal latency prolongation |
Percent F-wave latency prolongation |
Amplitude Conduction block |
Abnormal temporal dispersion |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Amplitude | ≥ 80% of LLN |
< 80% of LLN |
No. of nerves |
≥ 80% of LLN |
> 80% of LLN |
No. of nerves |
≥ 80% of LLN |
< 80% of LLN |
No. of nerves |
% | No. of nerves |
% | No. of nerves |
Abnormal parameters required |
| Albers 1985 (45) | >5 | > 15 | 2 | >10 | >20 | 2 | >20 | >20 | 2 | >30 | 2 | >30 | 1 | 1 |
| Albers 1989 (47) | >10 | >20 | 2 | >15 | >25 | 2 | >25 | >25 | 1 | >30 | 1 | >30 | 1 | 3 |
| Asbury 1990 (17) | >20 | >30 | 2 | >25 | >50 | 2 | >20 | >50 | 2 | >20* | 1 | >15 | 1 | 3 |
| Hadden 1998 (48) | >10¶ | >15 | 2 | >10 | >20° | 2 | >20 | >20 | 2 | >50† | 2 | — | — | 1 |
| Van denBergh 2004 (46) | >30 | >30 | 2 | > 50 | >50 | 2 | >25 | >50 | 2 | >50† | 2‡ | >30 | 2 | 1 |
LLN, lower limit of normal
†
distal amplitude > 20% of LLN
‡
alternatively 1 finding with another NCS abnormality
*
by area or amplitude
¶
distal amplitude >50% LLN
°
distal amplitude < LLN