Suction sampling technique for obtaining standardized cytologic specimens from the oral mucosa

To enhance the value of exfoliative cytology for the study of the oral mucosa, a simple apparatus was developed to permit adequate sampling of a specific site so that samples collected on different occasions could be compared. The device essentially consists of a collecting cup connected to a blood collection evacuation system. The collecting cup is a modified female half of a stainless-steel filter holder supporting a 13-mm-diameter cellulose filter of 0.05-microns pore size. Suction pressure is applied by means of a 10-mL glass tube of premeasured vacuum. After positioning the collecting cup on the selected site on the buccal mucosa, the vacuum (440 mm Hg) is applied for five seconds. The mucosa is drawn in against the filter, producing a monolayered imprint of cells. This sample may be disengaged from the filter by agitation into a solution; this allows quantitative cytologic studies, such as the measurement of cell numbers by an electronic counter or the estimation of the areas of cells and nuclei by computer-aided image analysis of Cytospin preparations. Five separate samplings from each of three test subjects produced a harvest of 3,000 to 7,000 epithelial cells per sample; the cellular areas ranged from 784 to 1,052 sq microns while the nuclear areas ranged from 18.4 to 21.8 sq microns.