Automated quantitative diagnosis system for dental diseases by optimum image processing

通过最佳图像处理的牙科疾病自动定量诊断系统

• 批准号: 14571791
• 负责人: YOSHIURA Kazunori
• 金额: $ 1.86万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14571791/
• 关键词: image processing; computer-aided diagnosis; digital dental imaging; diagnostic accuracy; caries detection; proximal caries; 自動診断

Many studies have reported that diagnostic accuracy of the digital dental imaging system is comparable to films. It may be due to the inadequate image display of the digital data The purpose of this study was to obtain maximum image information from digital dental imaging system by applying optimum image display of the digital data. Further aim was to develop a computer-assisted diagnosis system using caries diagnosis algorithm and optimized images. The results obtained are as follows.1.Collection of digital image dataTwenty-seven extracted teeth including caries of various grades were prepared. Pair of two teeth were radiographed with digital dental imaging system. Exposure time was varied in 8 steps including optimum exposure. Teeth were cut into halves and histopathology of proximal surfaces was assessed under the stereomicroscope. The final diagnoses were used as the "gold standards".2.Algorithm of automated outline extraction of proximal tooth surfaceTo detect proximal tooth surface automatically, an algorithm was developed using Wavelet transforms. It was possible to extract exact proximal tooth surface automatically by using this method.3.Algorithm of automated caries diagnosisA region of interest (ROI) was set at the interproximal position. An algorithm was developed to measure the pixel value changes vertical to the tooth surface. By moving along the proximal tooth surface, a profile of the pixel value changes. along the proximal tooth surface with certain thickness was obtained. Several representative values of the pixel value change have been determined.4.Evaluation of the diagnostic accuracy of this systemAutomated caries diagnosis was performed using the representative values extracted above. The diagnostic accuracy of the present system was comparable to that of the observers and better over some of the observers. We consider this system may be useful as a computer-assisted diagnosis system for proximal caries diagnosis.

许多研究已经报道，数字牙科成像系统的诊断准确性与胶片相当。这可能是由于数字数据的图像显示不充分。本研究的目的是通过应用数字数据的最佳图像显示，从数字牙科成像系统中获得最大的图像信息。进一步的目的是开发一个计算机辅助诊断系统，使用龋齿诊断算法和优化的图像。主要研究结果如下：1.数字图像数据的采集选取27颗离体牙，包括不同程度的龋损。用数字化牙科成像系统对两个牙齿进行X线摄片。暴露时间在8个步骤中变化，包括最佳暴露。将牙齿切成两半，并在立体显微镜下评估近端表面的组织病理学。以最终诊断结果为“金标准”。2.邻面牙体轮廓自动提取算法为了实现邻面牙体轮廓的自动提取，提出了一种基于小波变换的邻面牙体轮廓自动提取算法。3.龋病自动诊断算法在邻面位置设置感兴趣区域（ROI）。提出了一种测量垂直于齿面方向像素值变化的算法。通过沿着基牙表面移动，像素值的轮廓改变。沿着近牙面获得一定厚度的牙体。4.系统诊断准确性的评价利用上述提取的代表值进行龋齿自动诊断。本系统的诊断准确性与观察员的诊断准确性相当，并且优于一些观察员。我们认为这个系统可能是有用的，作为一个计算机辅助诊断系统的邻面龋诊断。