Assessment of voice quality after carotid endarterectomy.

Objectives: vocal cord paralysis is considered a rare complication of carotid endarterectomy (CEA), but alteration in voice quality may be more common. The aim of this prospective study was to evaluate the effect of CEA on voice quality and to correlate any changes with the extent of the dissection. DESIGN-MATERIAL-METHODS: thirty-five patients who underwent CEA were divided in two groups, according to the level of surgical dissection performed. The high-level dissection group was comprised of those patients that required mobilisation of hypoglossal nerve and division of the posterior belly of digastric muscle. The low-level dissection group included the rest. All the patients' voices were recorded and analysed digitally before CEA, one and three months after the operation. Voice data were measured for standard deviation of fundamental frequency, jitter, shimmer and normalised noise energy (NNE). All patients underwent a laryngeal examination pre- and post-operation.

Results: none of the patients had any vocal cord dysfunction on laryngoscopy. Significant changes of voice quality (jitter, shimmer, NNE) were noticed in the high-level dissection group (p<0.05) one month after the operation. Two months later, the voice changes had subsided, but still significant disturbances remained (jitter, shimmer).

Conclusions: voice-related disturbances are far more common following CEA than is generally believed and, although they seem to for the most part temporary, they deserve attention. Specifically, high-level surgical dissection seems to be a risk factor of postoperative vocal impairment.