The effect of microdebriders on tissue for histological diagnosis.

Microdebriders are an innovation in endonasal surgery which enable accurate and precise removal of tissue without damaging the surrounding mucosa. Concern has been expressed, however, that the instrument may render excised tissue unsuitable for histological diagnosis. This problem is further compounded by the fact that the Hummer (Stryker UK Ltd) microdebrider does not incorporate a mechanism for collecting specimens at the time of removal. Twenty-one patients with sinonasal polyposis underwent endoscopic sinus surgery using the microdebrider. Specimens were collected at the time of surgery via an in-line specimen trap. Simultaneous conventional biopsies of adjacent tissue were taken for comparison. The tissue was fixed in formalin then routinely processed to paraffin wax prior to staining with haematoxylin and eosin (H&E). A histological diagnosis was made in all 21 patients. A single unsuspected transitional cell papilloma was found. The remaining 20 specimens consisted of inflammatory nasal polypi. In two non-caseating granulomas were identified. Traumatic artefact was limited to the respiratory epithelium. The sub-epithelial tissue was unaffected and metaplastic epithelium appeared intact. The use of microdebriders does not preclude the submission of tissue for histological analysis. Tissue obtained has limited artefact and is suitable for pathological diagnosis.