Ocular Cytopathology

An atlas that features the cytologic findings of the normal features and diseases of the eye.

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Wednesday, September 21, 2005

Chapter-3-page3

CONJUNCTIVAL EPITHELIAL DYSPLASIA

Neoplasia of conjunctival epithelium is classified similarly to cervical neoplasia.[21]-25 Severity is graded by the thickness of the conjunctiva, which shows architectural and cytologic abnormalities. The criteria for dysplasia are the loss of normal cellular polarity, nuclear enlargement, nuclear irregularity, increased nucleus-to-cytoplasm size ratio, and increased numbers and abnormal forms of mitotic figures. Mild dysplasia involves up to one third of the thickness of the epithelium, moderate dysplasia up to two thirds, and severe dysplasia greater than two thirds. Carcinoma in situ is diagnosed when the entire thickness of the epithelium is involved. The clinical findings of the conjunctival and corneal hyperplasia, dysplasia, and carcinoma in situ are similar. A white epithelium with fimbriated edges and prominent blood vessels produces a surface opacity. Cytologic preparations from conjunctival dysplasia show slightly smaller conjunctival cells with hyperchromatic nuclei, an irregular chromatin pattern, and a high nucleus-to-cytoplasm ration (Figures 3-10 and 3-11). Although some authors have recommended cytologic examination of the conjunctiva as an excellent screening tool,2627 the cytologic grading of conjunctival dysplasia is not as reliable as grading of conjunctival dysplasia is not as reliable as grading of cervical disease. The reasons for this include the fact that the conjunctiva is very accessible to biopsy and assessment of margins is important in prognostication. Complete excision may be more important in determining recurrence than cell type or degree of dysplasia.28 In addition, dysplastic lesions of the conjunctiva are frequently keratinizing (Figure 3-12). Cytology from keratinized lesions often yields only surface anucleate Squamous cells so that the underlying neoplastic process may escape detection (Figures 3-13 and 3-14). Papilloma virus, especially type 16, has been identified in conjunctival swabs of many patients with conjunctival epithelial dysplasias by polymerase chain amplification. The virus is not found in all cases and its significance is yet to be elucidated.29 Intraepithelial neoplasia originating in the cornea is extremely rare. Most corneal intraepithelial dysplastic lesions are associated with limbal lesions,30 and dysplastic lesions confined to the cornea are rare.31, 32, 33, 34 Features considered precancerous in dysplastic lesions include the intracytoplasmic desmosomes, conspicuous tonofibrils, and dyskeratotic bodies and excessive basement membrane.35, 36 Clinically, hyperplastic lesions and dysplastic lesions are often distinguishable. Accurate cytologic diagnosis of hyperplasia is also difficult.37

CANALICULITIS
Inflammation of the lacrimal canaliculus that drains tears from the eye in the nasolacrimal duct is called canaliculitis. The most common cause of chronic canaliculitis is Actinomyces.38 Actinomyces israeli and Arachnia propionica (formerly Actinomyces propionicus) have been major organisms identified.39, 40, 41 The most common clinical findings are swelling of the soft tissue around the puncta and an expressible thick white exudates. Smears of the canalicular discharge show numerous neutrophils and sulfur granules composed of masses of filamentous forms with a fine branching pattern (Figure 3-15). A tissue gram stain (Brown-Brenn) is excellent for demonstrating the actinomyces organism (Figure 3-16). This method is cost effective to diagnose actinomyces canaliculitis.


References:
21. Cruess AF, et al. Can J Opthalmol, 1981.
22. Ash JE, Wilder HC. Epithelial tumors of the limbus. Am J Opthalmol 1942.
23. Winter FC, et al. Arch Opthalmol 1960.
24. Carroll JM, et al. Arch Opthalmol 1965.
25. Zimmerman LE. Squamous cell carcinoma and related conditions of the bulbar conjunctiva. In: Boniuk M, ed. Ocular and adnexal tumors, St. Louis, Mosby, 1964: 49-74.
26. Dykstra PC, Dykstra BA. The cytologic diagnosis of carcinoma and related lesions of the ocular conjunctiva and cornea. Trans Am Acad Opthalmol Otoaryngol 1968;73:979.
27. Irvine AR. Int Opthalomol Clin 1972.
28. Erie JC, et al. Opthalmology 1991.
29. McDonnell JM, McDonnell PJ, Sun YY. Polymerase chain reaction demonstration of human papilloma virus DNA in tissues and ocular surface swabs of patients with conjunctival epithelial neoplasia. Invest Opthalmol Vis Sci 1991;32;1285.
30. Waring GO, et al. Am J Opthalmol 1984.
31. Brown HH, et al. Cornea 1989.
32. Robertson MC. Corneal epithelial dysplasia. Ann Opthalmol 1984;16:1147-1150.
33. Geggel HS, et al. Ann Opthalmol 1985.
34. Cameron JA, et al. Am J Opthalmol 1991.
35. Dark AJ, et al. Br J Opthalmol 1980.
36. Campbell RJ, et al. Opthalmology 1981.
37. Jakobeic FA, to KW. Corneal epithelial dysmaturation. Invest Opthalmol Vis Sci 1991;32:1019.
38. Pine L, et al. Actinomyotic lacrimal canaliculitis Am J Syst Bacteriol 1960;49:1278-1288.
39. Pine L, Georg LK. Reclassification of Actinomyces propionicus. Int J Syst Bacteriol 1969;19:267-272.
40. Buchanan BB, et al. J Gen Microbiol 1962.
41. Seal DV, et al. Opthalmol 1981.


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