アブストラクト(19巻1号:神奈川歯学)

神奈川歯学

Japanese

Title : CTの口腔領域での基礎的研究
Subtitle : 原著
Authors : 鈴木信一郎
Authors(kana) :
Organization : 神奈川歯科大学放射線学教室
Journal : 神奈川歯学
Volume : 19
Number : 1
Page : 1-18
Year/Month : 1984 / 6
Article : 原著
Publisher : 神奈川歯科大学学会
Abstract : 「はじめに」Computed tomography (以下, CTと略す) は, 脳疾患の診断を目的として開発され, 1971年, HounsfieldとAmbroseによって試作機が完成した. その後のCTの発展は目ざましく, 全身用CTやダイナミックスタディが可能なCTが開発されてきた. したがって, 今日のCTは, 脳部のみならず全身の諸臓器についても, 画像診断の一翼をになっている. このような背景から, 最近, 口腔領域の疾患についてもCTによる臨床報告が増してきている. また, CTの機構は, 従来のX線撮影装置とは大きく異なっている. このため, CTの物理的特性や臨床応用のための基礎的研究も多数報告されているが, これらの研究の多くは, 軟組織の診断を想定したものである. しかし, CTを口腔領域に応用する際には, 歯や骨などの硬組織の存在を無視できない. したがって, CTの口腔領域での使用を想定したCTの特性を検討することは重要であると考えられる.
Practice : 歯科学
Keywords :

English

Title : Fundamental Studies for CT in the Oral Region
Subtitle :
Authors : Shinichiro SUZUKI
Authors(kana) :
Organization : Department of Radiology, Kanagawa Dental College
Journal : Kanagawa Shigaku
Volume : 19
Number : 1
Page : 1-18
Year/Month : 1984 / 6
Article : Original article
Publisher : Kanagawa Odontological Society
Abstract : Fundamental studies were attempted regarding the clinical application of CT (TCT-60A) in the oral region. The investigation assessed the following: 1) calculation of CT-No for oral hard tissues, 2) test for linearity CT-No vs. the linear attenuation coefficient in high X-ray attenuation materials, 3) observation of artifacts caused by dental materials and 4) measurement of patient doses of CT used at the maxillary sinus. The results obtained were as follows. 1) Calculated CT-No (E=70 KeV) values for oral hard tissues were enamel 3.51×103, dentine 2.40×103, cementum l.88×103, cortical bone 1.48×103 and mandible 1.O1×103. 2) Linearity for CT-No vs. the linear attenuation coefficient gave a good relative coefficient betwecn lucite and teflon, but linearity between lucite and aluminum was not good enough. 3) Three different artifacts from the copper rod were observed: (1) connection line artifact, (2) star-burst artifact and (3) figure-eight artifact. 4) Under shot caused by composite resin was observed, and artifact from both the radiopaque composite resin and amalgam were the same kinds as those from the copper rod. 5) Calculated CT-No (E=66 KeV) values for dental materials were copper 5.48×104, composite resin 1.24×103, radiopaque composite resin 4.65×103 and amalgam 2.27×105. 6) Absorbed doses of lenses and thyroid gland using CT at the mixillary sinus region were 59 mrad (59×10-2 mGy) and 17 mrad (17×10-2 mGy) for a single scanning. 7) The volume dose of the head under a single CT scanning was estimated as 820 g・rad (820×10-5 Kg・Gy) by the TLD method, and 900 g・rad (900×1-5 Kg・Gy) by the film dosimetry method. The difference in these values was considcred to be the effect arising from ununiformity of the X-ray beam.
Practice : Dentistry
Keywords :