Diagnostic Bedside Vestibuloocular Reflex Evaluation in the Setting of a False Negative Fistula Test in Cholesteatoma of the Middle Ear

Abstract

Background. False negative fistula testing in patients with chronic suppurative otitis media is a dilemma when proceeding to surgery. It is imperative to rule out a dead labyrinth or a mass effect secondary to the cholesteatoma in an otherwise normally functioning inner ear. We present a case series of three patients in whom a bedside vestibuloocular reflex (VOR) evaluation using a head impulse test was used successfully for further evaluation prior to surgery. Results. In all three cases with a false negative fistula test we were able to further evaluate at the bedside and were not only able to register the abnormal VOR but also localize its deterioration to a particular semicircular canal eroded by the fistula. Conclusion. Vestibuloocular reflex evaluation is mandatory in patients with suspected labyrinthine fistula due to cholesteatoma of the middle ear before proceeding to surgery. We demonstrate successful use of a bedside head impulse test for further evaluation prior to surgery in patients with false negative fistula test.

Case Report: Could Hennebert's Sign Be Evoked Despite Global Vestibular Impairment on Video Head Impulse Test? Considerations Upon Pathomechanisms Underlying Pressure-Induced Nystagmus due to Labyrinthine Fistula

“…PIN represents a peculiar finding in LF, although it may show a low diagnostic sensitivity. In fact, it might be underestimated due to a possible complete functional loss of inner ear sensors/afferents or the mass-induced canal plug exerted by concurrent middle ear pathologies might prevent pressure change transmissions to the endolymphatic spaces (16,18,19,28,37). Its pathomechanism is mainly attributed to the stimulation of SC ampulla, according to the site of erosion (14,(20)(21)(22)(23)(26)(27)(28).…”

Evaluation of the vestibulo-ocular reflex in patients with chronic otitis media

“…In the literature, research dedicated to assessing the results of the video head impulse test in patients with COM is scarce. 3 In a case study of three patients with radiologically and surgically confirmed horizontal SCC fistula secondary to COM, D’Albora et al 34 reported that the head impulse test at the bedside (without video) revealed the presence of refixation saccades in the three patients. Additionally, two of these patients underwent a video head impulse test, which showed a decrease in the VOR gain with consequent covert and overt saccades.…”

Development of semicircular canal occlusion

“…Simultaneously, with the development of diagnostic technology, HIT and semicircular canal multi-planar reconstruction (s-MPR) can be used appropriately to increase the positive rate of preoperative diagnosis. Indeed, the findings of intraoperative exploration is an important basis for diagnosis (D'Albora et al, 2017). Yamauchi et al (2014) first reported in 2014 the "underwater" endoscopic labyrinthine fistula closure technique.…”