Trigeminal nerve electrophysiological assessment in sickle cell anemia : correlation with disease severity and radiological findings

Abstract EN

Purpose The aim of our study was to assess, electrophysiologically, the possibility of associated subclinical trigeminal neuropathy in sickle cell anemia (SCA) patients and correlate the results with disease severity and findings of computerized tomography.

Materials and methods Fifty patients with SCA were included; 20 of these patients had clinical unilateral trigeminal neuropathy (group II), whereas the others were asymptomatic (group I).

Forty matched healthy individuals served as a control group.

Trigeminal evoked potential (TEP) and inferior alveolar nerve (IAN) conduction studies were carried out for all patients and controls.

Findings were correlated with the frequency of vaso-occlusive crisis, mental foramen (MF), and mandibular canal (MC) dimensions as measured by computerized tomography.

Results There were highly significantly longer N13, 19, and 20 latencies and reduced N13-P19 amplitude in patient groups in comparison with the controls (P<0.001).

There were delayed P19 latency, IAN latency, reduced IAN amplitude (P<0.05), and conduction velocity (P<0.001) in SCA patients with trigeminal neuropathy versus those without trigeminal neuropathy, and also in asymptomatic patients versus controls.

The vaso-occlusive crisis frequency in group II was correlated positively with all TEP waves’ latencies and IAN latency and correlated negatively with IAN amplitude, conduction velocity, and N13/P19 amplitude.

MF and MC dimensions were significantly reduced in group II in comparison with the controls (P<0.05).

MF height and MC diameter were correlated negatively with ipsilateral P19 latency.

Conclusion Subclinical trigeminal neuropathy may be associated with SCA.

The trigeminal nerve could be affected along its peripheral or the central pathway.

Central affection may occur as a result of lesions in its nuclei or at the somatosensory cortex.

Electrophysiological assessment is recommended in SCA patients to diagnose trigeminal neuropathy and detect the level of its affection.

This will provide new insights into its prevention and treatment