Comparison of 4 fixation and staining methods for the cytologic evaluation of ear canals with clinical evidence of ceruminous otitis externa

Abstract

We conclude that heat fixation does not improve the quality of ceruminous ear swab samples for cytologic evaluation, and propose a 1-step dip in the blue reagent alone as a rapid method of staining samples from canine ear canals.

Reproducibility of a semiquantitative method to assess cutaneous cytology

“…If inexperienced examiners asked, it was suggested to scan the slides initially using a lower magnification for areas with material present and subsequently evaluate the areas of interest with a higher magnification in more detail. This method corresponds to what is described to be appropriate for analysing cytological samples 1,9,14 . This may have led to a more uniform approach to assessing the slide specimens in the inexperienced group and thus a higher reproducibility than with a completely random approach.…”

Reproducibility of ear cytology in dogs with otitis externa

“…In previous studies, the otic debris or exudate was collected with only one cotton swab, which was then rolled on to two slides (Griffin and others 2007) or four slides (Toma and others 2006). The primary aim of the present study was to determine the reproducibility of sampling for otic cytology.…”

“…Many approaches to data collection have been utilised in the study of otitis externa. Two studies evaluated the microbial isolates and susceptibility patterns of dogs with otitis externa (Cole and others 1998, Graham-Mize and Rosser 2004), while others compared staining methods (Toma and others 2006), correlated cytological findings with culture results (Cole and others 1998, Graham-Mize and Rosser 2004) and/or their antimicrobial susceptibility patterns from parallel cultures (Graham-Mize and Rosser 2004). Recently, it was demonstrated that heat fixing has no effect on cytological results if yeast organisms are involved (Griffin and others 2007).…”

Skin and Subcutaneous Tissues

“…This debate has been addressed recently in two separate reports that show that samples taken as swabs for ear cytology do not need heat fixation (Toma et al, 2006;Griffin et al, 2007). Historically, sample collection of ear swabs has used heat fixation to ensure good-quality smears.…”