Nasal dermoid sinus cysts in the dog.

Area of Science:

• Veterinary Medicine
• Comparative Pathology
• Canine Surgery

Background:

• Nasal dermoid sinus cysts are rare congenital abnormalities.
• These cysts are developmental defects of the pre-nasal space.
• They can potentially lead to serious complications like cerebral abscesses.

Purpose of the Study:

• To characterize the clinical and morphologic features of nasal dermoid sinus cysts in dogs.
• To evaluate the outcome of surgical management for this condition.

Main Methods:

• Retrospective review of medical records from 1995 to 1999.
• Inclusion of six client-owned dogs with surgically excised nasal sinus tracts.
• Analysis of signalment, physical examination, surgical, histopathologic findings, and treatment outcomes.

Main Results:

• Six dogs (3 Golden Retrievers, 1 Springer Spaniel, 1 Cocker Spaniel, 1 Brittany Spaniel) were identified.
• Clinical signs included intermittent midline nasal discharge, unresponsive to antibiotics, with prior unsuccessful surgeries in 3 cases.
• Histopathology revealed tracts lined by stratified squamous epithelium with adnexal structures, confirming ectodermal developmental abnormalities.

Conclusions:

• The condition was diagnosed as nasal dermoid sinus cysts, analogous to the human congenital defect.
• Complete surgical excision of the tract and cyst resulted in a favorable outcome for all dogs.
• Nasal dermoid sinus cysts should be considered in the differential diagnosis for dogs presenting with discharging sinuses over the external nares.