An Automatable Method for Determining Adequacy of Thyroid Fine-Needle Aspiration Samples

Deconvolution Microscopy: A Platform for Rapid On-Site Evaluation (ROSE) of Fine Needle Aspiration (FNA) Specimens that Enables Recovery of the Sample

CONTEXT

Rapid on-site evaluation (ROSE) optimizes the performance of cytology, but requires skilled handling, and smearing can make the material unavailable for some ancillary tests. There is a need to facilitate ROSE without sacrificing part of the sample.

OBJECTIVE

We evaluated the image quality of inexpensive deconvolution fluorescence microscopy for optically sectioning non-smeared FNA tissue fragments.

DESIGN

A portion of residual material from 14 FNA samples was stained for 3 minutes in Hoechst 33342 and Sypro^TM Red to label DNA and protein respectively, transferred to an imaging chamber, and imaged at 200X or 400X magnification at 1 micron intervals using a GE DeltaVision inverted fluorescence microscope. A deconvolution algorithm was applied to remove out of plane signal, and resulting images were inverted and pseudocolored to resemble an H&E section. Five cytopathologists blindly diagnosed 2 to 4 representative image stacks per case (total 70 evaluations), and later compared them to conventional epifluorescent images.

RESULTS

Accurate definitive diagnoses were rendered in 45 of 70 (64%) total evaluations; equivocal diagnoses (atypical or suspicious) were made in 21 of 70 (30%). There were two false positive and two false negative "definite" diagnoses in three cases (4/70; 6%). Cytopathologists preferred deconvolved images compared to raw images (p< 0.01). The imaged fragments were recovered and prepared into a ThinPrep or cell block without discernable alteration.

CONCLUSIONS

Deconvolution improves image quality of FNA fragments compared to epifluorescence, often allowing definitive diagnosis while enabling the ROSE material to be subsequently triaged.