5% (350 of 511) of touch preparations
from percutaneous core biopsies, and 59.
marked as difficult included imprint (n = 1; 3.
b, Touch preparation
readily distinguishes this as a meningioma with the tight whorls and clusters of cells.
Discordant Cases: Intraoperative Touch Preparation
Versus Final Diagnosis of Sentinel Lymph Nodes (SLN) on Hematoxylin-Eosin Permanent Section Intraoperative Final Size of SLN Count SLN Count Metastasis (No.
Giemsa-stained touch preparations
demonstrate cytoplasmic granules.
Because repreparing the sample with direct touch preparations
may not be possible, at least two grids should be obtained when the specimen is collected.
One may chose to do core biopsies first, since cytologic preparations may be prepared by touch, crush, or scrape preparations of core biopsy tissue, thus saving the expense of an aspiration needle (Figs 2 and 3) Touch preparations
have previously been shown to adequately evaluate needle placement.
Since examination facilities or wards usually do not have the material to do direct touch preparations
onto EM grids, many health officials advocate placing samples into transport medium.
are recommended for pituitary adenomas, oligodendrogliomas, and lymphomas.