Human forniceal region is the stem cell-rich zone of the conjunctival epithelium.

The anterior surface of the eye is covered by several physically contiguous but histologically distinguishable epithelia overlying the cornea, limbus, bulbar conjunctiva, fornix conjunctiva, and palpebral conjunctiva. The self-renewing nature of the conjunctival epithelia makes their long-term survival ultimately dependent on small populations of stem cells. Hence, the objective of this study was to investigate the expression of the stem cell genes Sox2, OCT4, NANOG, Rex1, NES, and ABCG2 in cultured human conjunctival epithelium from different conjunctival zones, namely, the bulbar, palpebral and fornix zones. Three samples were taken from patients with primary pterygium and cataract (age range 56-66 years) who presented to our eye clinic at the UKM Medical Centre. The eye was examined with slit lamp to ensure there was no underlying ocular surface diseases and glaucoma. Conjunctival tissue was taken from patients who underwent a standard cataract or pterygium operation as a primary procedure. Tissues were digested, cultured, and propagated until an adequate number of cells was obtained. Total RNA was extracted and subjected to expression analysis of conjunctival epithelium genes (KRT4, KRT13, KRT19) and stem cell genes (Sox2, OCT4, NANOG, Rex1, NES, ABCG2) by reverse transcriptase-PCR and 2% agarose gel electrophoresis. The expression of Sox2, OCT4, and NANOG genes were detected in the fornical cells, while bulbar cells only expressed Sox2 and palpebral cells only expressed OCT4. Based on these results, the human forniceal region expresses a higher number of stem cell genes than the palpebral and bulbar conjunctiva.

Canaliculitis in supernumerary puncta and canaliculi.

We report the first case of supernumerary puncta and canaliculi presented with canaliculitis. A-59 year-old gentleman presented with painful swelling of the left lower lid for a week, which was associated with epiphora. The swelling was confined to the nasal aspect of the left lower lid (0.5×0.5 mm) with inflamed overlying skin. Two puncta (0.5 mm apart) were noted. The outer punctum at the normal anatomical position was a cul-de-sac while the inner punctum it the caruncle was patent. We described the embryology leading to supernumerary puncta and canaliculi to explain the paradoxical patency of the abnormally located punctum as well as the pathomechanism leading to canaliculitis. The patient was treated with oral cloxacillin 500 mg, 6 hourly for 5 days; the cellulitis subsided after three days.

Neurothekeoma palpebrae in association with multiple superficial angiomyxomas: Tegumental Angiomyxoma-Neurothekeoma syndrome (TAN syndrome).

We report a case of 10-year-old Indian girl with history of multiple superficial angiomyxoma, presented with three months history of painless right upper lid swelling. There were no visual dysfunctions. Previously, the patient had multiple superficial angiomyxoma (left pinna, left upper cheek, left upper limb, chest, right axilla, hard palate) and epidermal cyst (chin). The histopathological specimens were negative to S-100 protein antibody. Systemic review and family history was unremarkable. Excision biopsy and upper lid reconstruction were performed. Intraoperatively the tumor was multilobulated, firm, well encapsulated and did not invade the underlying tarsal plate. Histopathological features of the upperlid tumor were consistent with nerves sheath myxoma (neurothekeoma). To the best of the authors' knowledge, this is the first reported case of neurothekeoma in association with multiple superficial angiomyxoma.