Abstract
An inexpensive image-area and perimeter-length measurement system consisting of a personal computer and digital graphics tablet is described. A study to assess the efficacy of the system has shown that accuracy and reproducibility of area measurement increase with increasing size of cross-sectional area. The system generally underestimated all derived areas by less than 2%. Reproducibility of measurement, as defined by the coefficient of variation, was typically less than 2%; the greatest inaccuracies and variability occurring with shapes of smaller cross-sectional area. The system seems to be the least accurate when it measures shapes with rectangular symmetry. Neither direction of digitisation nor operator skill seemed to influence the measurement accuracy of the system.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Ramsey B, Lawrence CM. Measurement of Involved surface area in patients with psoriasis. Br J Dermatol 1991; 124: 565–70.
Godfrey KA, Flanagan GJ, Gerrard J, Lind T. A Microcomputer Measuring System applied to Real-Time Ultrasound Video Imaging. J Clin Ultrasound 1981 9: 309–13.
Criscuolo GR, Oldfield EH. Measurement of Intracranial Tissue Volume using Computed Tomographic Images and a Personal computer. Neurosurgery 1988; 23: 671–4.
Gowlands Hopkins NF, Jamiesob CW. Antibiotic concentration in the exudate of venous ulcers: the prediction of ulcer healing rate. Br J Surg 1983; 70: 532–4.
Bahmer FA. Measurement and figure in dermatology. Arch Dermatol 1986; 122: 501.
Bulstrode CJK, Goode AW, Scott PJ. Stereophotogammetry for measuring rates of cutaneous healing: a comparison with conventional techniques. Clin Sci 1986; 71: 437–43.
Hook GR, Rasband W. MacMeasure: A low cost, easy-to-operate quantitative morphometrics system. In: Bailey GW (ed.)Proceedings of the 45th Annual Meeting of the Electron Microscopy Society, 1987: 920–1.
Levell NJ, Lawrence CM. The use of a digitizer to measure are in dermatology. Physiol Meas 1993; 14: 401–10.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Taylor, R.J. The calculation of linear dimension and image area using a digitising tablet and personal computer. J Clin Monit Comput 12, 25–31 (1995). https://doi.org/10.1007/BF01142443
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01142443