Preauricular sinus is a congenital anomaly that is also termed preauricular pit, fistula, tract, or cyst.2 Fifty percent of its cases are unilateral and sporadic, out of which 60% are right-sided, influenced by right-handedness; this anomaly appears predominantly in females due to use of cosmetics.1 Preauricular sinus may be associated with deafness and renal anomaly, and median age of symptom appearance is 12–24 years and it ranges from 0 to 80 years.1–4,6–8 Twenty-five percent are estimated as symptomatic.4 However, clinically, infected preauricular sinus is usually misdiagnosed as pimples, furunculosis, dermoids, sebaceous cyst, or hemangioma.1,9 Because preauricular sinus is rarely mentioned in the medical literature, we did not think of this pathology until the plastic surgeon finally confirmed the sinus.1
If infectious symptoms, such as purulent discharge, erythema, swelling, and pain, are recurrent and uncontrollable, sinus excision becomes the treatment of choice after the infection subsides.3,7 Incision and drainage of abscess can cause an iatrogenic fistula and should be kept under wet dressing, as in the present case.3 Once wound healing is observed in the iatrogenic fistula and surrounding area, surgery can be performed.3 In the present case, the infection resolved immediately after initial incision and drainage.
The aim of surgery is the complete removal of the squamous epithelium because residual bacteria in the cells or debris can lead to recurrence.1–5,7,8 Recurrence rate has been reported to be between 0% and 42%.3,4,6,7 Limited knowledge, inexperienced surgeons, fewer references, and former surgery can increase the recurrence rate in addition to the existence of residual epithelial remnants.1–3,7 Superior extension of skin incision and radical excision, including some perichondrium or cartilage, under general anesthesia and guided by microscopic observation can decrease recurrence rates.2–4,6–8 On the other hand, local anesthesia, probe for sinus delineation, and postoperative sepsis can also lead to recurrence.2
In the present case, it was relatively easy to remove the surrounding tissues because extension of skin incision had already been created, and the layer of temporalis fascia, which is the medial limit of the tract, had already been separated and was easy to identify.4,6
To trace the sinus tract, methylene blue has been preferred over a lacrimal probe because the latter can lead to high recurrence rate.2–4,6,7 During skin closure, it is important to seal the dead space as tightly as possible by layer-by-layer suturing with or without drainage under compression dressing.2,4,5,7 Here, we followed this procedure as usual. Staphylococcus species and Escherichia coli are the main pathogens in an abscess.1,6–8 Usually, perioperative administration of pathogen-sensitive antibiotics is advisable.7 Sinus destruction by a sclerosant solution or electrodiathermy may be alternative therapies, but there is still controversy with regard to their effectiveness.2
Finally, in the present case, we suspected that the initial skin incision injured the sinus tract, resulting in debris dissemination. Subcutaneous residual hematoma might have accelerated the infection. We might have cut just toward the distal end of the sinus tract and the remnants might have discharged during washing and/or dressing. To date, no reports have described this complication after craniotomy. The orifice around the preauricular area should have been carefully inspected before craniotomy. Because neurosurgeons seldom encounter a preauricular sinus, they should consult a plastic surgeon or otolaryngologist if they suspect this anomaly. Complete sinus dissection before the initial surgery is recommended to prevent surgical site infection.
1. Adegbiji WA, Alabi BS, Olajuyin OA, et al. Presentation of preauricular sinus and preauricular sinus abscess in southwest Nigeria. Int J Biomed Sci. 2013;9:260–263
2. Tan T, Constantinides H, Mitchell TE. The preauricular sinus: a review of its aetiology, clinical presentation and management. Int J Pediatr Otorhinolaryngol. 2005;69:1469–1474
3. Huang WJ, Chu CH, Wang MC, et al. Decision making in the choice of surgical management for preauricular sinuses with different severities. Otolaryngol Head Neck Surg. 2013;148:959–964
4. Bae SC, Yun SH, Park KH, et al. Preauricular sinus: advantage of the drainless minimal supra-auricular approach. Am J Otolaryngol. 2012;33:427–431
5. Lai CS. Preauricular sinus as a cause of wound infection after rhytidectomy. Plast Reconstr Surg. 1998;102:584–585
6. Leopardi G, Chiarella G, Conti S, et al. Surgical treatment of recurring preauricular sinus: supra-auricular approach. Acta Otorhinolaryngol Ital. 2008;28:302–305
7. Currie AR, King WW, Vlantis AC, et al. Pitfalls in the management of preauricular sinuses. Br J Surg. 1996;83:1722–1724
8. Jin SG, Kim MJ, Park JM, et al. A case of subcutaneous hemangioma presenting as a preauricular sinus. Korean J Audiol. 2013;17:32–34
© 2014 American Society of Plastic Surgeons
9. Kumar KK, Narayanamurthy VB, Sumathi V, et al. Preauricular sinus: operating microscope improves outcome. Indian J Otolaryngol Head Neck Surg. 2006;58:6–8