Presentation of massive orbital hidrocystoma at birth: case report and review of the literature

Background: Hidrocystoma, or sudoriferous cyst, is an eyelid tumor originating from apocrine or eccrine sweat glands. Its presence in the orbit is relatively rare. Case presentation: A full-term female child with severe right eye extrusion was referred to our department two hours after birth. We performed cyst aspiration under ultrasonic guidance; 15 cc straw-colored fluid was obtained and proptosis resolved significantly. Orbital magnetic resonance imaging (MRI) showed a large unilocular retrobulbar mass with hypo-intensity in T1 and hyper-intensity in T2. The case underwent further daily ocular assessment until day 5; when proptosis began to worsen again. On day 6, under general anesthesia, we performed aspiration and then the cyst was completely removed with an intact wall through a trans-conjunctival incision. The diameter of the aspirated cyst was about 4 cm. In pathologic consultation, a cystic cavity lined by a layer of sweat duct like epithelium with apical snouts consistent with the diagnosis of apocrine hidrocystoma was reported. Conclusion: To date, in the literature, six other cases of orbital hidrocystoma have been reported in childhood with protean clinical pictures; none of which presented at birth. Herein, we introduce the first case report at birth and also provide a review on the literature. Our report strongly argues against the well reputed theory of traumatic origin for orbital hidrocystoma; it has been postulated that this tumor may be the result of sweat gland cells implantation through the orbit. We thereby suggest the possible presence of choristomatous ectopic sweat gland cells in the orbit during embryogenesis.