Congenital Sudoriferous Cyst within the Orbit Followed by Esotropia J. K. Chung, MD,1 Sung Jin Lee, MD,1 Sang Kyu Kang, MD,2 Song-Hee Park, MD1 Department of Ophthalmology1, Department of Plastic and Reconstructive Surgery2 Soonchunhyang University Hospital, Seoul, Korea Purpose: To report a case of congenital sudoriferous cyst of the orbit with esotropia. Methods: A 20-day-old male, born prematurely presented with a palpable lump on left upper lid. Orbital ultrasonography including color doppler image and orbital magnetic resonance image were performed to evaluate the lid lesion. The mass was excised and histologically examined. Complete ocular examination including visual acuity, duction, version, and the presence of strabismus were performed. Results: A well circumscribed round cystic mass, measuring 1.4×1.3 cm was noted at medial superior aspect of the left orbit. It compressed and displaced the left globe to inferior posterior position with intact optic nerve. Histopathologic examination showed the lesion to be a solitary sudoriferous cyst lined by two layers of cuboidal epithelial cells with eosinophilic cytoplasm. After the excision of the mass, limitations of extraocular muscle movements, esotropia, and amblyopia were noted. Conclusions: If an orbital cyst affects the globe or extraocular muscles, it should be excised as soon as possible to prevent strabismus and amblyopia especially in infant. Korean Journal of Ophthalmology 21(2):120-123, 2007 Key Words: Amblyopia, Esotropia, Sudoriferous cyst Sudoriferous cysts are fairly uncommon in the eyelid, where a cyst drives from the apocrine glands of Moll.1 Shields and Shields have described that this type of cyst typically occurs at the lid margin, but rarely appears within the orbit.1 Other previous literatures reported similar sites of lesion such as beneath the lids, canthal area, inferior orbital rim and floor.2-8 This tumor is rare in adults and even more rare for children. A sudoriferous cyst that appears as a congenital tumor is certainly most unusual.2 Although there are rare case reports of sudoriferous cysts in the orbit of children, this case report is the first to describe a congenital sudoriferous cyst of the orbit followed by esotropia. Case repo rt A 20-day-old male, born prematurely, with a palpable round lump on the upper left eyelid was presented to us for consultation by the department of pediatrics. The upper eyelid was closed due to the mass and could not be opened Received: September 28, 2006 Accepted: March 8, 2007 Reprint requests to Song Hee Park, MD. Department of Ophthal- mology, Soonchunhyang University Hospital, 657 Hannam-dong Youngsan-gu, Seoul 140-743, Korea. Tel: 82-2-709-9356, Fax: 82-2-798-7797, E-mail: scheye@hosp.sch.ac.kr * This has been previously presented at the 91st annual meeting of the Korean Ophthalmological Society, April, 2004. 120 nor everted. There was no change in the color or the size when the patient's head was placed in a dependent position or when the infant cried (Fig. 1A, B). His mother was in good general health and had not taken any medications during pregnancy. Examination of the infant showed no other congenital malformations. Ultrasonography (US) revealed a 1.1×1.3 cm round anechogenic cyst in the medial portion of the left orbit. It displaced the left eyeball to the posterior lateral portion. (Fig. 1C). Magnetic resonance images (MRI) of the orbits revealed a 1.4×1.3 cm round cystic mass with a low signal intensity in T1WI and a high signal intensity in T2WI. The left eyeball was compressed and displaced to the inferior-posterior portion of the eye socket by the mass. Although the mass was bound by the intracranial and nasal cavities, it was observed that the mild stimulation of the left optic nerve caused slight inferior displacement of the medial rectus muscle (Fig. 1D). Since there was visual axis encroachment in conjunction with eyeball displacement, surgical intervention was scheduled. The mass was excised via an approach through the skin. It was found to be attached with two stalks to the upper eyelid where it was carefully dissected and removed (Fig. 2A). The specimen was a grayish polypoid mass with fibrous band-like stalks and filled with a clear fluid. Histopathologically, the specimen consisted of a solitary cyst with a very thin cystic wall (Fig. 2B). Microscopically, it was lined by a double layer of non-keratinizing cuboidal and/or