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Solitary pulmonary nodule on helical dynamic CT scans: analysis of the enhancement patterns using a computer-aided diagnosis (CAD) system.

Choi EJ, Jin GY, Han YM, Lee YS, Kweon KS - Korean J Radiol (2008 Sep-Oct)

Bottom Line: On the Bland and Altman plot, the net enhancement difference between the CAD system and direct personal drawing was not significant (within +/- 2 standard deriation).The sensitivity, specificity, PPV, NPV and accuracy of diagnosing malignant SPNs using direct drawing was 92%, 89%, 79%, 92% and 88%, respectively.The CAD system was a useful tool for diagnosing malignant SPNs.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Chonbuk National University Hospital and Medical School, Research Institute for Medical Science, Chonbuk, Korea.

ABSTRACT

Objective: We wanted to investigate the usefulness of a computer-aided diagnosis (CAD) system in assisting radiologists to diagnosis malignant solitary pulmonary nodules (SPNs), as compared with diagnosing SPNs with using direct personal drawing.

Materials and methods: Forty patients with SPNs were analyzed. After the pre-contrast scan was performed, an additional ten series of post-contrast images were obtained at 20-second intervals. Two investigators measured the attenuation values of the SPNs: a radiologist who drew the regions of interest (ROIs), and a technician who used a CAD system. The Bland and Altman plots were used to compare the net enhancement between a CAD system and direct personal drawing. The diagnostic characteristics of the malignant SPNs were calculated by considering the CAD and direct personal drawing and with using Fisher's exact test.

Results: On the Bland and Altman plot, the net enhancement difference between the CAD system and direct personal drawing was not significant (within +/- 2 standard deriation). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of diagnosing malignant SPNs using CAD was 92%, 85%, 75%, 96% and 88%, respectively. The sensitivity, specificity, PPV, NPV and accuracy of diagnosing malignant SPNs using direct drawing was 92%, 89%, 79%, 92% and 88%, respectively.

Conclusion: The CAD system was a useful tool for diagnosing malignant SPNs.

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Related in: MedlinePlus

Bland and Altman plot showing difference between using CAD system and direct personal drawing.A. Difference in peak enhancement between using CAD system and direct personal drawing.B. Difference in net enhancement between using CAD system and direct personal drawing. X-axis represented average values of using CAD system and direct personal drawing while y-axis represented difference in peak enhancement and net enhancement between using CAD system and direct personal drawing. Dashed lines represent mean value of two measurements and lines above and below it represent 95% limits of agreement. Peak enhancement was out of 95% limits of agreement only in one case, while net enhancement was out of 95% limits of agreement in two cases.
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Figure 2: Bland and Altman plot showing difference between using CAD system and direct personal drawing.A. Difference in peak enhancement between using CAD system and direct personal drawing.B. Difference in net enhancement between using CAD system and direct personal drawing. X-axis represented average values of using CAD system and direct personal drawing while y-axis represented difference in peak enhancement and net enhancement between using CAD system and direct personal drawing. Dashed lines represent mean value of two measurements and lines above and below it represent 95% limits of agreement. Peak enhancement was out of 95% limits of agreement only in one case, while net enhancement was out of 95% limits of agreement in two cases.

Mentions: Higher PE and NE were observed by direct personal drawing and by using the CAD system (Table 1). As seen from the numerical value of the enhancement of the PE and NE, direct personal drawing showed higher enhancement than did the CAD system. There were differences (mean: 34.9 HU; 95% CI: 28.0-41.8) between the PE using CAD systems (mean: 67.2 ± 27.1 HU) and the PE using the direct personal drawing (mean: 32.3 ± 28.1 HU). In addition, there were differences (mean: 6.9 HU, 95% CI: 1.1-12.7) between the NE using the CAD systems (mean: 25.9 ± 27.4 HU) and the NE using direct personal drawing (mean: 32.8 ± 24.9 HU). On the other hand, as found from the enhancement patterns of PE and NE, the Bland and Altman plot showed that the mean difference was 95% of the individual differences ± 2 standard deriation (SD) (Fig. 2). With 15 HU or more of NE as a cutoff value for differentiating malignant and benign nodules, the sensitivity for the diagnosis of malignant SPNs using the CAD system was 92% (12/13), the specificity was 52% (14/27), the PPV was 48% (12/25), the NPV was 93% (14/15) and the accuracy was 65% (26/40), respectively. However, the sensitivity, specificity, PPV, NPV and the accuracy obtained by direct personal drawing of malignant SPNs was 100% (13/13), 37% (10/27), 43% (13/30), 100% (10/10), and 58% (23/40), respectively (Table 2).


Solitary pulmonary nodule on helical dynamic CT scans: analysis of the enhancement patterns using a computer-aided diagnosis (CAD) system.

Choi EJ, Jin GY, Han YM, Lee YS, Kweon KS - Korean J Radiol (2008 Sep-Oct)

Bland and Altman plot showing difference between using CAD system and direct personal drawing.A. Difference in peak enhancement between using CAD system and direct personal drawing.B. Difference in net enhancement between using CAD system and direct personal drawing. X-axis represented average values of using CAD system and direct personal drawing while y-axis represented difference in peak enhancement and net enhancement between using CAD system and direct personal drawing. Dashed lines represent mean value of two measurements and lines above and below it represent 95% limits of agreement. Peak enhancement was out of 95% limits of agreement only in one case, while net enhancement was out of 95% limits of agreement in two cases.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2627214&req=5

Figure 2: Bland and Altman plot showing difference between using CAD system and direct personal drawing.A. Difference in peak enhancement between using CAD system and direct personal drawing.B. Difference in net enhancement between using CAD system and direct personal drawing. X-axis represented average values of using CAD system and direct personal drawing while y-axis represented difference in peak enhancement and net enhancement between using CAD system and direct personal drawing. Dashed lines represent mean value of two measurements and lines above and below it represent 95% limits of agreement. Peak enhancement was out of 95% limits of agreement only in one case, while net enhancement was out of 95% limits of agreement in two cases.
Mentions: Higher PE and NE were observed by direct personal drawing and by using the CAD system (Table 1). As seen from the numerical value of the enhancement of the PE and NE, direct personal drawing showed higher enhancement than did the CAD system. There were differences (mean: 34.9 HU; 95% CI: 28.0-41.8) between the PE using CAD systems (mean: 67.2 ± 27.1 HU) and the PE using the direct personal drawing (mean: 32.3 ± 28.1 HU). In addition, there were differences (mean: 6.9 HU, 95% CI: 1.1-12.7) between the NE using the CAD systems (mean: 25.9 ± 27.4 HU) and the NE using direct personal drawing (mean: 32.8 ± 24.9 HU). On the other hand, as found from the enhancement patterns of PE and NE, the Bland and Altman plot showed that the mean difference was 95% of the individual differences ± 2 standard deriation (SD) (Fig. 2). With 15 HU or more of NE as a cutoff value for differentiating malignant and benign nodules, the sensitivity for the diagnosis of malignant SPNs using the CAD system was 92% (12/13), the specificity was 52% (14/27), the PPV was 48% (12/25), the NPV was 93% (14/15) and the accuracy was 65% (26/40), respectively. However, the sensitivity, specificity, PPV, NPV and the accuracy obtained by direct personal drawing of malignant SPNs was 100% (13/13), 37% (10/27), 43% (13/30), 100% (10/10), and 58% (23/40), respectively (Table 2).

Bottom Line: On the Bland and Altman plot, the net enhancement difference between the CAD system and direct personal drawing was not significant (within +/- 2 standard deriation).The sensitivity, specificity, PPV, NPV and accuracy of diagnosing malignant SPNs using direct drawing was 92%, 89%, 79%, 92% and 88%, respectively.The CAD system was a useful tool for diagnosing malignant SPNs.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Chonbuk National University Hospital and Medical School, Research Institute for Medical Science, Chonbuk, Korea.

ABSTRACT

Objective: We wanted to investigate the usefulness of a computer-aided diagnosis (CAD) system in assisting radiologists to diagnosis malignant solitary pulmonary nodules (SPNs), as compared with diagnosing SPNs with using direct personal drawing.

Materials and methods: Forty patients with SPNs were analyzed. After the pre-contrast scan was performed, an additional ten series of post-contrast images were obtained at 20-second intervals. Two investigators measured the attenuation values of the SPNs: a radiologist who drew the regions of interest (ROIs), and a technician who used a CAD system. The Bland and Altman plots were used to compare the net enhancement between a CAD system and direct personal drawing. The diagnostic characteristics of the malignant SPNs were calculated by considering the CAD and direct personal drawing and with using Fisher's exact test.

Results: On the Bland and Altman plot, the net enhancement difference between the CAD system and direct personal drawing was not significant (within +/- 2 standard deriation). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of diagnosing malignant SPNs using CAD was 92%, 85%, 75%, 96% and 88%, respectively. The sensitivity, specificity, PPV, NPV and accuracy of diagnosing malignant SPNs using direct drawing was 92%, 89%, 79%, 92% and 88%, respectively.

Conclusion: The CAD system was a useful tool for diagnosing malignant SPNs.

Show MeSH
Related in: MedlinePlus