Impression Debridement of Corneal Lesions

Current Perspectives on Ophthalmic Mycoses

“…Spherical, multinucleate yeast-like cells (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) m in diameter) with single broad-based bud and refractile double-contoured walls; generally larger than those of cryptococci (301). Seen in KOH mounts of necrotic material or in tissue sections, and generally extracellularly (215,338), and in culture at 37°C.…”

“…Moreover, conventional techniques of debriding corneal ulcers require great dexterity and magnification to stay within the confines of the lesion and to avoid perforation if imminent; the material obtained is sometimes difficult to spread on slides, and the cells seen may be distorted or crushed with loss of spatial relationships (18). An impression debridement technique, using filter paper, has been described that overcomes some of these drawbacks (18). In this technique, a cellulose acetate filter paper (of the type used for conjunctival impression cytology) is applied to the ulcerated part of the cornea and gentle pressure applied; the filter paper with debrided corneal tissue sticking to it is then removed and stained.…”

Collection of corneal impression cytology directly on a sterile glass slide for the detection of viral antigen: An inexpensive and simple technique for the diagnosis of HSV epithelial keratitis – A pilot study

“…It is one of the most preferred techniques in ocular surface sampling in dry eye, keratitis and conjunctivitis [7]. Conventionally, impression cytology is collected using cellulose acetate filter paper [8], Biopore membrane [6] or Nitrocellulose membrane [9]. These membranes are expensive and may not be available in all laboratories.…”

Comparative study of impression smear with conventional mechanical corneal scrapping by potassium hydroxide (10%KOH) in diagnosis of fungal keratitis

“…In a study by Arora et al, impression debridement of corneal lesions has been done for various types of corneal ulcers, removal of superficial foreign bodies, filaments of filamentary keratitis and superficial infiltration around cataract-related exposed corneoscleral sutures. 13,26 In a prospective study of 171 cases of clinically suspected fungal corneal ulcers, although cultures were positive in 88 eyes (51.46%), the fungus could be demonstrated by KOH preparation in 94.3% (83 of 88) of culture-proved cases and 93.6% (160 of 171) of the overall eyes. Gopinathan et al, in their large series (1354 eyes) of fungal keratitis, have reported the diagnostic utility of smears of corneal scrapings using KOH preparation, calcofluor white (CFW), gram and giemsa-stains.…”