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This web-based atlas consists of 349 images representing a range of morphologic findings seen on both conventional smears and liquid based preparations. The majority of these images are from cervical/vaginal preparations; however, some anal-rectal preparations are also illustrated. Some are classic examples of an entity while others have been selected to illustrate interpretive dilemmas or “borderline” cytomorphologic features that may not be interpreted in the same way by all cytologists. The images have gone through a multistage review process.

Click here to learn more about the image selection process.

For each image, the preparation type, morphologic criteria and interpretation using the 2001 Bethesda System terminology are provided. Clinical history and follow-up are included if available.

A subset of these images was used for the web-based Bethesda Interobserver Reproducibility Project (BIRP) which involved over 500 participants providing independent interpretations online. The resulting histograms showing the distribution of interpretations for these 77 images are presented on this website.


You can search for images several ways using the left navigation bar to filter by:

  • The Bethesda System atlas chapters: The chapters correspond to the Bethesda atlas (Solomon D., Nayar R. (editors). The Bethesda System for Reporting Cervical Cytology, Second Edition. New York: Springer-Verlag, 2004.)
  • The Bethesda atlas figure number (chapter # and figure #)
  • The Bethesda terminology pull up table
  • Keyword(s)
  • Specimen preparation type: Conventional smear; ThinPrep; Histology; SurePath
  • Bethesda Interobserver Reproducibility Project (BIRP) images with interobserver variability histograms


You also have the opportunity to take a “self test” comprised of 17 images with masked interpretations. After you provide your interpretation, your response is tallied along with all previous participants.

We welcome your comments (see Feedback menu button) and we hope you enjoy the site!

Ritu Nayar, MD and Diane Solomon, MD on behalf of all the Bethesda atlas authors and contributors. 9/03

collage of cytopathology images
Definitions of terms used in this site