A sialo-cutaneous fistula is a communication between the skin and a salivary gland or duct discharging saliva. Trauma and iatrogenic complications are the most common causes of this condition. Treatments include aspiration, compression, and the administration of systemic anticholinergics; however, their effects are transient and unsatisfactory in most cases. We had a case of a patient who developed an iatrogenic sialo-cutaneous fistula after wide excision of squamous cell carcinoma in the parotid region that was not treated with conventional management, but instead completely resolved with the injection of botulinum toxin. Based on our experience, we recommend the injection of botulinum toxin into the salivary glands, especially the parotid gland, as a conservative treatment option for sialo-cutaneous fistula.
A sialo-cutaneous fistula is defined as a communication between the skin and a salivary gland resulting in the discharge of saliva from the skin [
An 80-year-old male was referred to us with squamous cell carcinoma of the left pre-auricular area that was confirmed through incisional biopsy (
On the fifth postoperative day, we discovered exudate from the base of the skin graft through the slit incision site (
We decided to use botulinum toxin type A injection because of concern for graft failure due to increased sialorrhea that was not controlled by conventional compression dressings. Using a tuberculin syringe, we administered a transcutaneous injection of 25 IU of the toxin at a point 0.5 cm above the site of the fistula at the surgical incision line and administered another 25 IU injection 0.5 cm anterior from that point. The injections were performed only for the superficial parotid gland in order to avoid post injection facial nerve paralysis. The discharge draining from the sialo-cutaneous fistula was considerably reduced after the second day of injection. The patient fully recovered within a week without any complications such as graft shearing or failure (
Sialo-cutaneous fistula is one of the most common complications of post-trauma injury and head and neck surgery. There has not been a consensus on the appropriate treatment of this condition, which range from conservative methods such as needle aspiration, pressure dressings, and anti-sialogogue therapy, to radiotherapy and surgical approaches such as duct repair, diversion, ligation, drainage systems, and even parotidectomy [
The parotid gland receives both sensory and autonomic innervation. Sensory innervation is supplied by the auriculotemporal nerve, a branch of the mandibular nerve. The autonomic innervation controls the rate of saliva production. Preganglionic parasympathetic fibers leave the brain stem from the inferior salivatory nucleus in the glossopharyngeal nerve and then run along its tympanic branch followed by the lesser petrosal branch into the otic ganglion. There, they synapse with postganglionic fibers which reach the gland by hitch-hiking via the auriculotemporal nerve, a branch of the mandibular nerve [
Botulinum toxin has transient effects but has many advantages including the fact that it is non-destructive, dose-dependent, has good target area localization, and has minimal systemic side effects [
Recently, botulinum toxin has been used in some autonomic diseases such as achalasia, hyperhidrosis, and Frey's syndrome [
Considering the 18,938 face-lift procedures performed in South Korea in 2014, the incidence of sialo-cutaneous fistula could be substantial and surgeons should consider the administration of botulinum toxin as a non-invasive and effective treatment modality [
Based on our experience, we recommend the injection of botulinum toxin as a conservative treatment option for parotid sialo-cutaneous fistula. Botulinum toxin avoids the side effects caused by systemic anticholinergic drugs and is cost-effective. However, it is essential that the accurate anatomical landmarks are recognized by a trained injector before proceeding.
No potential conflict of interest relevant to this article was reported.