Computer-aided diagnosis system for bone scintigrams from Japanese patients: importance of training database

Abstract

AimComputer-aided diagnosis (CAD) software for bone scintigrams have recently been introduced as a clinical quality assurance tool. The purpose of this study was to compare the diagnostic accuracy of two CAD systems, one based on a European and one on a Japanese training database, in a group of bone scans from Japanese patients.MethodThe two CAD software are trained to interpret bone scans using training databases consisting of bone scans with the desired interpretation, metastatic disease or not. One software was trained using 795 bone scans from European patients and the other with 904 bone scans from Japanese patients. The two CAD softwares were evaluated using the same group of 257 Japanese patients, who underwent bone scintigraphy because of suspected metastases of malignant tumors in 2009. The final diagnostic results made by clinicians were used as gold standard.ResultsThe Japanese CAD software showed a higher specificity and accuracy compared to the European CAD software [81 vs. 57 % (p < 0.05) and 82 vs. 61 % (p < 0.05), respectively]. The sensitivity was 90 % for the Japanese CAD software and 83 % for the European CAD software (n.s).ConclusionThe CAD software trained with a Japanese database showed significantly higher performance than the corresponding CAD software trained with a European database for the analysis of bone scans from Japanese patients. These results could at least partly be caused by the physical differences between Japanese and European patients resulting in less influence of attenuation in Japanese patients and possible different judgement of count intensities of hot spots.

Computer-assisted interpretation of planar whole-body bone scintigraphy in patients with newly diagnosed prostate cancer

“…Thus, the diagnostic properties therefore likely differ in newly diagnosed patients, especially when PSA screening is used, versus in patients with recurrent disease. Most prior studies have not reported predictive values[9,10,15]. Tokuda and colleagues published NPV very similar to our data (98-100% in prostate cancer).…”

“…The high sensitivities and specificities are in line with previous reports[9,10,12,17]. Most studies with EXINI Bone BSI have been performed in patients with metastatic disease in whom the prevalence of metastasis varied from 15 to 40%[10,12,15]. In clinical practice, the true reference is seldom known and the PPV and NPVs are of major importance.…”

Diagnostic performance of a computer-assisted diagnosis system for bone scintigraphy of newly developed skeletal metastasis in prostate cancer patients: search for low-sensitivity subgroups

“…The cutoff level was set at ANN = 0.5 throughout the study according to other Japanese studies [7, 8].

The sensitivity was also calculated as a function of the diagnostic setting (staging period, follow-up).

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13. From telemedicine to modeling and proactive medicine

“…If annotations and measurements are precisely performed such a diagnosis can be extremely useful not only for the diagnosed patient but also as a valuable source of knowledge and good practices in imaging data analysis. The importance of a proper database has been pointed out in papers regarding building CAD systems [71,72]. A special consultation session can even be organized which aims at selecting certain features in the imaging data.…”