Impression cytology of the ocular surface: a review.
OBJECTIVE
To historically review the technique of impression cytology as a minimally invasive diagnostic tool for ocular surface pathology.


METHODS
A comprehensive review of published literature cited in PubMed since the first description of impression cytology in 1977 up to date has been undertaken.


RESULTS
A wide range of processing methods have been adapted to the technique of impression cytology (from conjunctiva, cornea or limbus): regular light microscopy with different stainings, transmission and scanning electron microscopy, immunofluorescence, immunocytochemistry, polymerase chain reaction analysis, immunoblotting analyses, or flow cytometry. At present, it is widely used as a non-invasive alternative to the full-thickness biopsy for the obtention of epithelial cells from the ocular surface.


CONCLUSIONS
Impression cytology represents a non- or minimally invasive biopsy of the ocular surface epithelium with no side effects or contraindications. It has demonstrated to be a useful diagnostic aid for a wide variety of processes involving the ocular surface. In addition, and mainly during the last decade, its use as a research tool has experienced an enormous growth and has greatly contributed to the understanding of ocular surface pathology.
Calonge
Margarita
M
Instituto Universitario de Oftalmobiología Aplicada (IOBA), University of Valladolid, Ramón y Cajal, 7, E-47005 Valladolid, Spain. calonge@ioba.med.uva.es
Diebold
Yolanda
Y
Sáez
Victoria
V
Enríquez de Salamanca
Amalia
A
García-Vázquez
Carmen
C
Corrales
Rosa M
RM
Herreras
José M
JM
D001706:Biopsy / Q000379:methods; D003229:Conjunctival Diseases / Q000473:pathology*; D003316:Corneal Diseases / Q000473:pathology*; D015352:Dry Eye Syndromes / Q000175:diagnosis; D004847:Epithelial Cells / Q000473:pathology; D006801:Humans