First-bite syndrome: a review of 29 patients with parapharyngeal space tumor.

OBJECTIVE

The aim of this study is to clarify the etiology of first-bite syndrome.

METHODS

A total of 29 consecutive patients treated with a surgical resection for parapharyngeal space tumor between April 1999 and April 2005 were retrospectively reviewed.

RESULTS

Nine cases of first-bite syndrome were developed. Eight of those patients had undergone surgical ablation of the cervical sympathetic chain and/or external carotid artery. In two patients who underwent ablation of the sympathetic chain but in whom first-bite syndrome did not develop, the superior cervical ganglion was probably preserved.

CONCLUSION

The present findings strongly indicate that loss of sympathetic innervation to the parotid gland from the superior cervical ganglion causes first-bite syndrome. They also suggest that some residual or autonomous activity of the superior cervical ganglion could prevent development of first-bite syndrome even if the lower sympathetic trunk was ablated.