Welcome to Classifications and Online Calculators in Radiology

This site was build along with the Atlas of Radiology Images to support your knowledge in radiology.

You will find here:

that are used in radiology and related fields with free access.


  • Some pages are accompanied by illustrations
  • All pages contain tags for easy navigation

The concept

The concept of this website is based on a previous site that was founded in 2008 and is still up and running. The website is composed as a book, where all sources are properly referenced, according to a good practice in scientific publications.

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    Doubling time - calculation of growth rate of a lesion or a mass

    Calculating doubling time of focal lesions or massess can give a hint, whether it has a malignant or rather benign growth dynamics. Doubling time of malignant lesions is between 30 and 500 days with a median of 100 days.

    First examination Date (d/m/yy)
    Diameter [mm]
    Second examination Date (d/m/yy)  
    Diameter [mm]


    1. Collins VP, Loeffler RK, Tivey H. Observations on growth rates of human tumors. Am J Roentgenol Radium Ther Nucl Med. 1956 Nov;76(5):988–1000.
    2. Schwartz M. A biomathematical approach to clinical tumor growth. Cancer. 1961 Dec;14:1272–94.
    3. Mehrara E, Forssell-Aronsson E, Ahlman H, Bernhardt P. Specific Growth Rate versus Doubling Time for Quantitative Characterization of Tumor Growth Rate. Cancer Res. 2007 Apr 15;67(8):3970–5.

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