Primary isolated osteoma cutis causing eyelid deformation and strabismus in a dog

Osteoma cutis describes bone formation in skin and is well documented in the medical literature, but veterinary reports are few. We report a single case of a juvenile samoyed that was referred for assessment of a superior eyelid anomaly. Exploratory surgery and histopathology revealed the presence of mature, lamellar bone within the superior eyelid. The histologic appearance was consistent with primary osteoma cutis. The presence of the ossification within the deep dermis of the eyelid was associated with an abnormal conformation causing trichiasis, keratitis and dorsal strabismus. Identification of the osseous lesion during surgery and its removal was curative with no recurrence of disease during the 32 month follow-up period.