Objective: This study aimed to determine how the smooth pursuit neck torsion (SPNT) test is affected by various diseases associated with disturbances in balance and arising in the neck, in the posterior intracranial fossa, and in the labyrinth in patients having such conditions, and to compare the findings with those in healthy subjects.
Study design: This study was a consecutive, prospective, double-blind clinical study.
Setting: This study was conducted with ambulatory patients in a tertiary referral center (i.e., a county hospital).
Patients: Studied were 75 patients with whiplash-associated disorders (WAD) of at least grade II, according to the Quebec classification, all of whom had been injured in car accidents. Of these, 50 patients reported dizziness and 25 did not. CONTROL SUBJECTS: Twenty patients had vertigo of central origin with positive central nervous system findings, 20 patients had Meniere's disease, and 30 subjects were healthy.
Intervention: The SPNT test is a smooth pursuit eye movement test. The subjects are placed in a neutral position, and then they turn 45 degrees to the right and to the left. The difference between the average gain in neutral and torsion positions is the test parameter. In addition to the SPNT test, the authors performed saccade tests, auditory brain stem response, and the caloric test.
Main outcome measures: In the two WAD groups, neck torsion reduced the SP gain (p < 0.001), but in control patients with central and peripheral vertigo and in the healthy control subjects, it did not.
Results: The sensitivity of the SPNT test in the WAD group with dizziness was 90% and the specificity was 91%. The sensitivity in the WAD group without dizziness was 56%.
Conclusion: The SPNT test seems to be useful for diagnosing cervical dizziness, at least in patients with WAD having symptoms of dizziness, because it has a high sensitivity and specificity.