Unusual carcinomas of the lacrimal gland: epithelial-myoepithelial carcinoma and myoepithelial carcinoma.

serrata rarely cause the syndrome. Our atypical patients had posterior horseshoe retinal tears, exhibited cells in the anterior chamber without other signs of ocular inflammation, and had elevated IOP, which normalized after retinal detachment repair. Although no macrophages were identified, the cells observed in the anterior chamber of the affected eyes may represent an anterior migration of photoreceptors and other cell types. The pathway into the anterior chamber has been well described previously. Numerous mechanisms have been proposed for the elevated IOP in this syndrome, but mechanical obstruction owing to photoreceptor outer segment deposition in the trabecular meshwork remains the most widely accepted mechanism, although it is unproven by histopathologic studies. Electron microscopic analysis of the aqueous humor in our cases revealed photoreceptor outer segments at varying stages of degeneration and sizable lipid-containing aggregates (Figure 2). Although the origin of these structures is uncertain, photoreceptor segment membranes contain a high content of cholesterol and lipid. The presence of these membrane-bound structures may represent an aggregation of photoreceptor outer segments, which in their bulky nature contribute to a mechanical reduction in aqueous outflow through the trabecular meshwork. These cases comprise an atypical form of Schwartz-Matsuo syndrome with posterior retinal tears and electron microscopic evidence of degenerating photoreceptor outer segments, which appear to aggregate in the anterior chamber of affected eyes. Our findings add to the case documentation of Schwartz-Matsuo syndrome and provide more insight into the origin and mechanism of glaucoma associated with RRD.