The diagnostic value of isolated preponderance in caloric testing
Abstract
Objectives: An isolated directional preponderance (PD) on bithermal caloric testing leaves many doubts to neurootology. It is considered by some to be as a transient, benign disorder (Halmagy, GM et al). We tried to elucidate if the PD can be considered important for the clinical diagnosis, without anamnesis.
Methods: A retrospective study of 136 electronystagmographies, with PD isolated in caloric test, without spontaneous nystagmus, rotational preponderance or canal paresis (labyrinth asymmetry) was performed. The study group was selected from our outpatients that follow the exclusion rules that were: PD >= 40%, canal paresis < 25% and without spontaneous nystagmus.
Results: Of the 136 patients, 86.02% had a conclusive examination, being the majority of them diagnosed with of vascular syndrome (38.23%) followed by metabolic disorders (13.23%) and cervical syndrome (10.29%); Ménière was 2.2% of total, and VPPB 8.82%. Central vertigo had expressive appearance 7.35%. We wanted to point that it is possible to determine the accuracy in diagnostic in cases of isolated directional preponderance.