Breaking the Myth of Central Neurological Complications in Stapedial Artery Surgery.

Abstract

To the Editor: We read with great interest the review article by Goderie et al. (1) entitled “Surgical management of a persistent stapedial artery.” In line with the author's opinion, we confirm the idea that the stapedial artery can be coagulated without complications. Today, no surgeon need feel any “doubt” when facing a persistent stapedial artery (2,3). The risk of “hemiplegia, or central auditory, or vestibular impairment” is not even a theory, but rather an extrapolation from an embryological study in rats, where a few animals exhibited partial dysgenesis of the basilar artery with a primitive vascular plexus vascularizing the brainstem. As this primitive vascular plexus was anastomosed with the stapedial artery, the authors hypothesized that a persistent stapedial artery in humans might be capable of partially vascularizing the brainstem, if associated with basilar artery dysgenesis (4). This abnormality has never been described in humans, and there is no evidence that the rat embryos would ever have survived with this vascular abnormality. In addition, rats differ from humans in that the stapedial artery normally persists in adult rats whereas this is not the case in humans. As a result, surgeons should not be misled by false risks in cases of symptomatic persistent stapedial artery. As demonstrated by Goderie et al., in cases of pulsatile tinnitus, coagulation of the persistent stapedial artery relieves the symptoms. This is currently the only treatment possible, and as a result, it should be offered to these patients. In cases of conductive hearing loss without pulsatile tinnitus, the surgical treatment needs to be discussed with hearing aids options. Regarding the surgical technique, it is necessary to differentiate between two situations: conductive hearing loss is either caused by the stapedial artery only, or by otosclerosis (or any other cause) with the persistent stapedial artery playing no, or only a minor, role. In the first situation, the surgical treatment requires simply transecting the stapedial artery without any additional actions on the stapes. In the second situation, the main cause of hearing loss needs to be treated. In most cases, the cause is otosclerosis, which explains why stapedotomy (or stapedectomy), with or without stapedial artery transection, improves hearing. To differentiate between these two situations, surgeons must look at the computerized tomography scan to identify any causes of conductive hearing loss, including otosclerosis and a persistent stapedial artery (e.g., the absence of the foramen spinosum) (Fig. 1). During the operation, surgeons must also assess whether or not the stapedial artery touches the stapedial arch, and if the stapes are fixed. Finally, the mobility of the stapes should be tested again after transecting the artery, to determine whether the stapedial artery was the only cause of the hearing loss.FIG. 1: Computerized tomography scan showing a stapedial artery (SA) too small to be responsible for the conductive hearing loss, but associated with a thickened footplate and demineralization of the antefenestram. This indicates otosclerosis as the cause of the hearing loss.This method should help surgeons manage persistent stapedial arteries as minor anatomical variations, and offer symptomatic patients the best treatment possible.