Higher-bit digitization utilized for exposure compensation with digital imaging system for dental office

高位数字化用于牙科诊所数字成像系统的曝光补偿

• 批准号: 09671933
• 负责人: HAYAKAWA Yoshihiko
• 金额: $ 1.92万
• 依托单位: TOKYO DENTAL COLLEGE
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09671933/
• 关键词: Digital imaging system; Dental Radiography; Exposure compensation; Quantification; Digital image processing; 歯科X線撮影

(1) Results from software features of six digital imaging systems for intra-oral radiography. Six digital systems, CDR, PanaDigital(PD), RVG, Sens-A-Ray(SAR), Visualix(VIX) and Digora, were used. Function for the full-mouth survey were evaluated. Software features were classified into three functions, such as image acquisition, image display and image saving. CDR and RVG provided the display disposition to arrange images of the full-mouth survey. Some systems needed several times of clicking prior to acquisition, but no operation for VIX. The period for waiting exposure ranged from 15 sec to an infinity. Automatic exposure compensation was set at PD, RVG and Digora by default. Pixel values were proportional to exposures with CDR, SAR and VIX(linear mode). After the exposure, the captured image was automatically saved with CDR, SAR and Digora. Images were stored in each pateint's directory with CDR, RVG and SAR, Ten-bit storage was employed with PD. The TIF format was adopted by RVG, SA … More R andVIX. The RVG and VIX employed the JPEG. Advantages and drawbacks learned through our experiences were clarified. Software features showed differences. These systems are provided for the use at a dental chair side. They should be designed so that operations are not complicated.(2) Results from the evaluation of the new storage phosphor-based compted radiography system for dental office. The denOptix CR system is applicable for both intraoral and panoramic radiographic examinations. The DenOptix uses an imaging plate. We examined the new features, different pitches for laser-scanning and the automatic range control (ARC). A jaw phantom and a head phantom were used. Images were captured with the ARC working. Laser-scanning pitch was set at either 150, 300 or 600 dpi. A piece of the Dental X-ray Beam Filter Kit reduced X-ray output to 30%. Even when two pieces were used, the DenOptix was still capable of obtaining intraoral images with acceptable image quality. The DenOptix has also the capability of obtaining panoramic images with a little detriment of noise with the lowest exposure. The ARC worked to compensate both under- and over-exposures and resulted the wide exposure range. The compensation of over-exposures may result in images created with an exposure that gives the patient a higher dose than necessary.(3) Results from the evaluation of a digital panoramic radiography system. The Dimax is adigital panoramic radiography system which uses a stationary, narrow two-dimensional detector in place of a moving cassette. The purpose of this study is to evaluate software features as an interface to the operator and the image quality related to exposure. Software features were evaluated as four major functions, such as image acquisition, display, storage and transmission. The tissue-equivalent phantom was used to evaluate the exposure reduction. Some excellent software features, for example a combination of hardware and software, ease to operate, care of patient' privacy, were found. The inadequate image quality due to under-exposures was avoidable since the exposure compensation and the gamma conversion worked well. To some extent such compensation worked for over-exposures, but the operator could easily recognize exceeded exposures. Less

（1）来自六个数字成像系统的软件功能，用于射线内射线照相。使用了六个数字系统，即CDR，Panadigital（PD），RVG，Sens-A射线（SAR），Visualix（Vix）和Digora。评估了全口调查的功能。软件功能分为三个功能，例如图像采集，图像显示和图像节省。 CDR和RVG提供了展示处置，以安排全口调查的图像。有些系统需要在获取之前几次单击，但没有对VIX进行操作。等待的时期从15秒到无穷大。默认情况下，在PD，RVG和Digora设置了自动曝光补偿。像素值与CDR，SAR和VIX（线性模式）的暴露成正比。曝光后，用CDR，SAR和Digora自动保存捕获的图像。图像用CDR，RVG和SAR存储在每个PatchInt的目录中，使用PD进行十位存储。 TIF格式由RVG，SA…更多RANDVIX采用。 RVG和VIX采用JPEG。通过我们的经验学到的优势和缺点得到了阐明。软件功能显示差异。这些系统可用于在牙科椅侧使用。它们应该被设计为以使操作不复杂。（2）评估新的基于磷光磷的牙科办公室的放射线系统的结果。 DENOPTIX CR系统适用于口腔内和全景射线照相检查。 Denoptix使用成像板。我们检查了新功能，激光扫描的不同音高和自动范围控制（ARC）。使用了下颌幻影和头部幻影。图像是通过弧线工作捕获的。将激光扫描的音高设置为150、300或600 dpi。牙科X射线梁滤清器套件的一块将X射线输出降低到30％。即使使用了两片，Denoptix仍然能够获得具有可接受图像质量的口腔内图像。 Denoptix还具有获取全景图像的能力，并以最低暴露的噪声确定噪声。 ARC致力于补偿不足和过度曝光，并导致广泛的暴露范围。过度曝光的补偿可能会导致通过暴露产生的图像，从而使患者的剂量比必要的剂量更高。（3）评估数字全景射线照相系统的结果。 Dimax是一种充分的全景X射线照相系统，它使用固定的，狭窄的二维检测器代替移动的盒式盒子。这项研究的目的是评估软件功能作为与操作员的接口以及与曝光有关的图像质量。将软件功能评估为四个主要功能，例如图像采集，显示，存储和传输。组织等效的幻影用于评估暴露量的减少。发现了一些出色的软件功能，例如，硬件和软件的结合，易于操作，护理患者的隐私。由于暴露补偿和伽马转换效果很好，因此由于曝光不足而引起的图像质量不足。在某种程度上，这种补偿用于过度曝光，但操作员可以很容易地认识到超过的暴露。较少的

项目成果

早川吉彦: "Rotational panoramic radiography with digital readout : CCD-based sensor coupled.."Radiology. 213Suppl. 500 (1999)

Yoshihiko Hayakawa：“带数字读出的旋转全景放射线摄影：基于 CCD 的传感器耦合..”放射学 213Suppl。

早川吉彦: "口腔内挿入用のCCDセンサー、イメージングプレートのX線透過性" 歯科放射線. 37・4. 316-319 (1997)

早川佳彦：“口腔内插入用 CCD 传感器和成像板的 X 射线透明度”牙科放射学 37・4（1997 年）。

早川吉彦: "Algorithm of pre-processing for displaying digitized images with computed.."Japanese Journal of Medical Physics. 19・Suppl. 141-142 (1999)

Yoshihiko Hayakawa：“用计算机显示数字化图像的预处理算法”日本医学物理学杂志 19・增刊 141-142（1999）

早川吉彦: "Improvement in digital readout methods applied for intraoral radiography : CMOS-.."Radiology. 213Suppl. 500 (1999)

Yoshihiko Hayakawa：“口内放射线照相数字读出方法的改进：CMOS-..”放射学 213Suppl。

早川吉彦: "Assessing the image quality of a CCD-based digital intraoral radiography system"Bulletin of Tokyo Dental College. 41・1. 9-14 (2000)

Yoshihiko Hayakawa：“评估基于 CCD 的数字口腔内放射线摄影系统的图像质量”，东京牙科学院公告 41・1（2000 年）。