1. A Rare Case of Central Corneal Dermoid: Clinico-Pathological and Immunocytochemistry Analysis Jagadesh C. Reddy,MD Inderjeet Kaur, PhD; Vivek Singh, PhD; Dilip Kumar Mishra, MD; Syed Hameed, MSc The authors have no financial interests in the subject matter of this presentation ID: 17657

2. Purpose To report a rare case of central corneal dermoid and to see the immunocytological differences from limbal dermoid to ascertain its origin Methods A 12-day old child was brought to the clinic by non consanguineous parents with a complaint of white opacity in the left eye since birth. Antenatal history: hydronephrosis on foetal ultrasonography

3. Methods Examining the child under anesthesia showed an elevated brownish mass with vascularization in the central cornea of the left eye Ultrasound bio microscopy showed kerato-irido- lenticular adhesion The child underwent penetrating keratoplasty at the age of 3 months

4. Methods Central corneal dermoid UBM- showing kerato-irido-lenticular adhesions

5. Still images from the surgical video 8 mm partial thickness trephination Irido-lenticular adhesions to the posterior surface of the cornea Anterior sub capsular cataract at the inferior margin of the pupil Graft in place with 16 interrupted 10/0 nylon sutures

6. Hematoxylin and Eosin staining of limbal and corneal dermoid (10x) limbal dermoid corneal dermoid smooth muscle blood vessel sebaceous gland ecrine sweat gland hair shaft with pilo sebaceous gland

7. Blank Cornea Limbal dermoid Corneal dermoid The Immunohistochemical Staining: CK3 marker Higher expression of differentiation marker Ck3 was found in all the cells of corneal epithelium and in the stratified epithelium of limbal dermoid but not in the corneal dermoid

8. Blank Cornea Limbal dermoid Corneal dermoid The Immunohistochemical Staining: Smooth muscle actin Protein (αSMA) Smooth muscle actin protein (αSMA) was localized to the blood vessels predominantly in the corneal and limbal dermoid and absent in the normal cornea

9. The Immunohistochemical Staining: limbal stem cell specific markers ABCG2 and P63 The basal epithelial layer of limbal dermoid and hair shaft stained positively for ABCG2 and P63 but not detected in the cornea and corneal dermoid ABCG2 a subtype of the ATP binding casette family of cell surface transport protein P63 is an important marker for the stemcellness normally expressed by discreet clusters of basal limbal epithelium but no expression in corneal epithelium Blank CorneaLimbal dermoid Corneal dermoid

10. Immunohistochemical characteristics of normal cornea, limbal dermoid and corneal dermoid S.NoMarkersCornea Limbal dermoid Corneal dermoid 1CK3++++SEND 2αSMAND++BV 3ABCG2ND+BEND 4 P63ND++BE and HSND +++ indicates strong staining;++good; +faint; ND not detected; SE stratified epithelium; BV Blood vessels; BE basal epithelium; HS hair shaft. Clinical Outcome At 18 months the graft remained clear. Though there was minimal amount of cataract, the child maintained clear visual axis and there were no signs of amblyopia At 12 months the child underwent left nephrectomy for a nonfunctioning kidney

11. Conclusions The preliminary findings of this study suggest probably a different origin of limbal and corneal dermoid Validation with extended list of epithelial and mesenchymal markers that are involved in early growth and development of cornea could lead to a better understanding of the pathogenesis of dermoids in the eye

12. References Newsom R, Ayliffe W, Dhar-Munshi S, Kirkham N, Liu C. Management of corneal opacification associated with Xia K, Wu L, Liu X, Xi X, Liang D, Zheng D, et al.Mutation in PITX2 is associated with ring dermoid of the cornea. J Med Genet 2004;41:e129. Watson et al, Current Eye Research, 2013: 38(8): 835 842.