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By John Gorcsan III, William A. Mandarino, Lee G. Deneault, Shigeki Morita, Akihiko Kawai, Bartley P. Griffith, Robert L. Kormos. The International Journal of Cardiac Imaging 10, 103–111, June 1994. Publisher title, full byline, author affiliations and abstract verified at link.springer.com/article/10.1007/BF01137705 . Abstract: six excised dog hearts were perfused ex vivo; an intraventricular balloon supplied volume and a micromanometer catheter supplied pressure. Automated echocardiographic borders measured mid-ventricular short-axis area. Three volume runs in 1 mL increments per heart yielded 1,080 simultaneous observations. The experiment compared pressure-area with pressure-volume relationships; it did not establish clinical validation. Full article not inspected.

Lee G. Deneault coauthored the 1994 primary experiment relating image-derived ventricular area, measured pressure and balloon-reference volume. The publisher gives the full name, and the paper's abstract describes automated boundary detection linked to simultaneous computerized pressure-area acquisition.^[ref]

This work addresses an important distinction between correlation and numerical agreement. A surrogate can track changes extremely consistently while retaining a scale or offset error. For original reference volumes 10, 20 and 30 mL, let a hypothetical estimator give $\hat{V}=1.2V+5$ mL. It yields 17, 29 and 41 mL. The Pearson correlation coefficient is exactly one, yet every estimate is biased upward and the change scale is 20% high.

Likewise, a strong relation between pressure-area and pressure-volume measurements does not by itself make area and volume interchangeable. Their units and geometric conversion differ. A useful validation compares the actual relationship, its repeatability and the conditions under which the surrogate is applied.

The primary abstract reports both correlations and fitted-curve comparisons, then states that clinical application remains to be validated.^[ref] This establishes Deneault's participation in a concrete imaging-validation study without attributing the illustrative error model or an individually invented role to him.