JP2006208010A - Radiation detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiation detector capable of carrying out an RI detection method without using an expensive detector in the RI detection method for a sentinel lymphaden, and provided with a radiation shield onto an inexpensive and widely spread radiation detector provided always availably in almost all the medical facilities using a radioactive pharmaceutical. <P>SOLUTION: This radiation detector for the sentinel lymphaden is provided with a cylindrical radiation shielding part capable of preventing an effect from a dosage portion when diagnosing the sentinel lymphaden, and capable of providing specificity compatibly while keeping radiation detection sensitivity from the sentinel lymphaden, and a substantially cylindrical connection part of enhanced specificity capable of specifying an accurate position of the sentinel lymphaden. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は特異性の高い放射線遮蔽体を具備した放射線検出装置に関する。 The present invention relates to a radiation detection apparatus having a radiation shield with high specificity.

近年の医学では、悪性腫瘍の転移診断に腫瘍特異的に集積する放射性物質を体内に投与し、その集積を測定することが行われている。 In recent medicine, radioactive substances that accumulate in a tumor-specific manner are used in the diagnosis of metastasis of malignant tumors, and the accumulation is measured.

例えば乳癌、食道癌および大腸癌等に於いて、腫瘍細胞の転移を最初に受けるリンパ節に腫瘍細胞が確認できなければそれより下流域のリンパ節廓清を行わないという治療法が進められている。その治療法により患者の精神的および身体的負担を軽減し、予後の回復を向上させることができる。こうした背景から放射性医薬品を用いたいわゆるセンチネルリンパ節診断が重視されつつある。 For example, in breast cancer, esophageal cancer, colorectal cancer, etc., a treatment method is underway in which lymph node dissection is not performed downstream if tumor cells cannot be identified in the lymph node that initially receives tumor cell metastasis. . The treatment can reduce the mental and physical burden on the patient and improve the prognostic recovery. From such a background, so-called sentinel lymph node diagnosis using a radiopharmaceutical is being emphasized.

このセンチネルリンパ節の検出法（ＲＩ検出法）は、腫瘍部位近傍および／または乳輪周辺に放射性医薬品を投与してその流れを追跡し、リンパ系に移行した放射性医薬品が最初に集積するリンパ節（センチネルリンパ節）を検出するものである。 In this sentinel lymph node detection method (RI detection method), a radiopharmaceutical is administered in the vicinity of the tumor site and / or around the areola, the flow is traced, and the lymph node where the radiopharmaceutical that has migrated to the lymphatic system first accumulates. (Sentinel lymph node) is detected.

ところが、センチネルリンパ節に集積する放射能量は、投与部位に集積する放射能量の約１／１００程度と小さいため、投与部位とセンチネルリンパ節との位置が比較的隣接した場合、投与部位に残存する不要な放射線に影響されるので、センチネルリンパ節の検出が困難になることがある。 However, since the amount of radioactivity accumulated in the sentinel lymph node is as small as about 1/100 of the amount of radioactivity accumulated at the administration site, it remains at the administration site when the administration site and the sentinel lymph node are relatively adjacent to each other. Detection of sentinel lymph nodes can be difficult due to unwanted radiation.

そのため小型で特異性および感度の高いプローブと呼ばれている専用の検出器を用いた検出装置（例えば特許文献１参照）が用いられているが、専用の放射線検出装置は非常に高価なため、この有用な検出法が医療現場に広く普及し難い状況にあった。そこでセンチネルリンパ節のＲＩ検出には、安価で普及性のある検出装置が医療関係者より望まれていた。
特表２００２−５２８７２９ Therefore, a detection device using a dedicated detector called a small, highly specific and sensitive probe (see, for example, Patent Document 1) is used, but the dedicated radiation detection device is very expensive, This useful detection method was difficult to spread widely in the medical field. Therefore, a medical device is desired for an inexpensive and popular detection device for RI detection of sentinel lymph nodes.
Special table 2002-528729

本発明はセンチネルリンパ節のＲＩ検出法において、高価な検出装置を用いることなくその実施を可能とするもので、放射性医薬品を使用している医療施設のほとんどに常備されている安価で普及性の高い放射線検出器に放射線遮蔽体を具備した放射線検出装置を提供する。 The present invention enables the RI detection of sentinel lymph nodes to be carried out without using an expensive detection device, and is inexpensive and widely used in most medical facilities using radiopharmaceuticals. A radiation detection apparatus having a radiation shield on a high radiation detector is provided.

本発明は、放射線を検出するための検出部を有する放射線検出器と、前記放射線検出器とケーブルで連結され、放射線量を計数率として表示するための測定部とで構成された放射線測定器、および前記放射線検出器の側面に入射する放射線を遮断するための、一端に略円錐中空形部を有する筒形放射線遮蔽部と、前記略円錐中空形部に連結し、放射線の検出特異性を調節するための略筒形連結部とで構成された放射線遮蔽体、とを備えることを特徴とする放射線検出装置を用いて前記課題を解決したものである。 The present invention relates to a radiation detector comprising a radiation detector having a detection unit for detecting radiation, and a measurement unit connected to the radiation detector by a cable and displaying a radiation dose as a counting rate, And a cylindrical radiation shielding part having a substantially conical hollow part at one end for blocking radiation incident on the side surface of the radiation detector, and coupling to the substantially conical hollow part to adjust the detection specificity of radiation The above-mentioned problems are solved by using a radiation detection device comprising a radiation shield composed of a substantially cylindrical connecting part for achieving the above.

より詳細には、センチネルリンパ節診断の際に、投与部位からの放射線の影響を防止し、且つセンチネルリンパ節からの放射線検出感度を保ちながら特異性も兼ね備えた筒形放射線遮蔽部と、さらにはセンチネルリンパ節の正確な位置を特定することのできる、より特異性を高めた略筒形連結部とを備えたセンチネルリンパ節用放射線検出装置に関する。 More specifically, when diagnosing the sentinel lymph node, a cylindrical radiation shielding unit that prevents radiation from the administration site and also has specificity while maintaining radiation detection sensitivity from the sentinel lymph node, and The present invention relates to a radiation detection apparatus for a sentinel lymph node, which is capable of specifying an accurate position of the sentinel lymph node and includes a substantially cylindrical connecting portion with higher specificity.

本発明の放射線検出装置を用いることにより、一部の医療施設にしか置かれていない高価な放射線検出装置を使用しなくてもセンチネルリンパ節診断を広く普及させることができる。それにより、多くの症例において生体組織を過度に切除しない治療法が選択可能となり、患者の身体的および精神的負担を軽減することができる。 By using the radiation detection apparatus of the present invention, sentinel lymph node diagnosis can be widely spread without using an expensive radiation detection apparatus that is only available in some medical facilities. This makes it possible to select a treatment method that does not excessively excise living tissue in many cases, thereby reducing the physical and mental burden of the patient.

また、投与部位側に補助遮蔽を用いなくてもセンチネルリンパ節の検出が可能と成り、術前術中に煩雑な操作を行わずに診断ができる。 In addition, the sentinel lymph node can be detected without using auxiliary shielding on the administration site side, and diagnosis can be performed without performing complicated operations before and after surgery.

尚、筒形放射線遮蔽部を用いただけでセンチネルリンパ節の検出が可能だが、投与部位近傍にセンチネルリンパ節が有る場合、略円錐中空形部に略筒形連結部を更に接続することにより、投与部位からの放射線の影響を低減しつつ特異性を高め、センチネルリンパ節の検出を容易にすることができる。 Although it is possible to detect sentinel lymph nodes using only a cylindrical radiation shielding part, if there is a sentinel lymph node in the vicinity of the administration site, administration can be performed by further connecting a substantially cylindrical connecting part to the substantially conical hollow part. The specificity can be increased while reducing the influence of radiation from the site, and the detection of sentinel lymph nodes can be facilitated.

以下実施の形態を示す図面と共に本発明を説明する。
図１は本発明放射線検出装置の一部である放射線検出器３と放射線遮蔽体１３の縦断面説明図である。 The present invention will be described below with reference to the drawings showing embodiments.
FIG. 1 is a longitudinal sectional view of a radiation detector 3 and a radiation shield 13 which are a part of the radiation detection apparatus of the present invention.

放射線検出器３は、放射線を検出する検出部１とその発光をカウントして電気信号に変換する出力部２とから成っている。また、放射線遮蔽体１３は、筒形放射線遮蔽部１１と略筒形連結部１２とから構成され、更に筒形放射線遮蔽部１１は、略円錐中空形部１０を有している。 The radiation detector 3 includes a detection unit 1 that detects radiation and an output unit 2 that counts the emitted light and converts it into an electrical signal. The radiation shield 13 includes a cylindrical radiation shield 11 and a substantially cylindrical connecting part 12, and the cylindrical radiation shield 11 further has a substantially conical hollow part 10.

検出部１は、放射線の入射により発光するシンチレータであり、検出された発光は出力部２により電気信号に変換される。検出部１および出力部２の形状は特に問わない。 The detection unit 1 is a scintillator that emits light upon incidence of radiation, and the detected light emission is converted into an electrical signal by the output unit 2. The shapes of the detection unit 1 and the output unit 2 are not particularly limited.

筒形放射線遮蔽部１１は、検出部に入射する放射線を遮断するもので、放射線検出器３を挿入する為の開口端を有する略筒形形状であり、その反対側には略円錐中空形部１０を有している。尚、特異性の違う略円錐中空形部１０を予め用意し、センチネルリンパ節の放射能量に応じて略円錐中空形部１０が適宜交換できる構造に成っていればなお良い。
筒形放射線遮蔽部１１の長手方向の長さは特に問わないが、投与部位からの強い放射線を避けるために放射線検出器３を傾けてセンチネルリンパ節を検出する際、投与部位から検出部に入射する放射線を遮断できる長さであれば良い。また、横または後ろ方向から検出部に入射する放射線量は少ないので、筒形放射線遮蔽部１１の遮蔽厚は開口端側に向かって段階的に薄くすることもできる。 The cylindrical radiation shielding unit 11 blocks radiation incident on the detection unit, and has a substantially cylindrical shape having an open end for inserting the radiation detector 3. 10. In addition, it is preferable that the substantially conical hollow portion 10 having different specificity is prepared in advance and the substantially conical hollow portion 10 can be appropriately replaced according to the radioactivity of the sentinel lymph node.
The length of the cylindrical radiation shield 11 in the longitudinal direction is not particularly limited, but when detecting the sentinel lymph node by tilting the radiation detector 3 in order to avoid intense radiation from the administration site, it enters the detection unit from the administration site. As long as the radiation can be blocked, the length may be sufficient. Further, since the amount of radiation incident on the detection unit from the lateral or rear direction is small, the shielding thickness of the cylindrical radiation shielding unit 11 can be gradually reduced toward the opening end side.

筒形放射線遮蔽部１１に連結する略円錐中空形部１０は、投与部位に残存した多量の放射線を遮断するもので、円錐中空形状を有している。また、その先端はセンチネルリンパ節を特異的に且つ感度良く測定するために、細径孔を有している。その細径孔の形状は、円形、楕円形、三角形、四角形等その如何を問わないが、放射線が均一に入射する円形が望ましい。また、センチネルリンパ節の平均的な直径が５〜１０ｍｍなので、前記細径孔の直径は、５ｍｍ以上が望ましい。 The substantially conical hollow portion 10 connected to the cylindrical radiation shielding portion 11 blocks a large amount of radiation remaining at the administration site, and has a conical hollow shape. In addition, the tip has a small-diameter hole for specifically and sensitively measuring the sentinel lymph node. The shape of the small-diameter hole is not particularly limited, such as a circle, an ellipse, a triangle, and a quadrangle, but a circle in which radiation is uniformly incident is preferable. Moreover, since the average diameter of the sentinel lymph node is 5 to 10 mm, the diameter of the small-diameter hole is preferably 5 mm or more.

前記略円錐中空形部１０の先端には、さらに特異性を高めるための着脱自在な略筒形連結部１２を取り付けることができ、その形状は、筒形形状を有している。 A detachable substantially cylindrical connecting portion 12 for further increasing the specificity can be attached to the tip of the substantially conical hollow shape portion 10, and the shape thereof has a cylindrical shape.

尚、筒形放射線遮蔽部１１および略筒形連結部１２は図２ａ、ｂおよびｃの本発明略円錐中空形部の他の形態を示す説明図にあるように一体に成っていても良く、略筒形連結部１２の形状は、図２ａに示すような先端よりも基端の直径が大きい先細りとなっている略筒形状、図２ｂに示すような直径が均一な筒形状および図２ｃに示すような逆ラッパ形状でも良い。また、前記筒形放射線遮蔽部１１および略筒形連結部１２の遮蔽厚は、特に限定しないが、特異性、感度および操作性を勘案すると５ｍｍ以下が適当である。また、筒形放射線遮蔽部１１および略筒形連結部１２の材質は、一般にγ線の遮蔽に利用されている遮蔽金属ならばその如何を問わないが、遮蔽効果、加工性および費用等を考慮すると鉛が適している。また、筒形放射線遮蔽部１１の外面には衛生面を保つため、ステンレス製のカバーで覆うことが好ましいが、更に衛生面を担保するには、放射線遮蔽体１３と放射線検出器３の全体をビニール等で覆うことが望ましい。 In addition, the cylindrical radiation shielding part 11 and the substantially cylindrical connecting part 12 may be integrated as shown in the explanatory views showing other forms of the substantially conical hollow part of the present invention in FIGS. 2a, b and c. The shape of the substantially cylindrical connecting portion 12 is as follows: a substantially cylindrical shape having a taper having a base diameter larger than the distal end as shown in FIG. 2a; a cylindrical shape having a uniform diameter as shown in FIG. 2b; and FIG. A reverse trumpet shape as shown may be used. The shielding thickness of the cylindrical radiation shielding portion 11 and the substantially cylindrical connecting portion 12 is not particularly limited, but is preferably 5 mm or less in consideration of specificity, sensitivity, and operability. The material of the cylindrical radiation shielding part 11 and the substantially cylindrical connecting part 12 is not particularly limited as long as it is a shielding metal generally used for shielding γ rays, but the shielding effect, workability, cost, etc. are considered. Then lead is suitable. Moreover, in order to maintain a hygienic surface on the outer surface of the cylindrical radiation shielding portion 11, it is preferable to cover it with a stainless steel cover. However, in order to further secure the hygienic surface, the radiation shield 13 and the radiation detector 3 as a whole are covered. It is desirable to cover with vinyl.

図３は本発明放射線検出装置を示す説明図であり、図１で示した放射線検出器３と放射線遮蔽体１３に加え、放射線検出器３からの電気信号を伝達するケーブル５とその電気信号を放射線量の計数率として表示する測定部４とを備えている。 FIG. 3 is an explanatory view showing the radiation detection apparatus of the present invention. In addition to the radiation detector 3 and the radiation shield 13 shown in FIG. 1, a cable 5 for transmitting an electrical signal from the radiation detector 3 and the electrical signal are shown. And a measurement unit 4 that displays the radiation dose as a counting rate.

次に、実施例を用いてさらに説明するが、本発明は実施例により何ら制約されるものではない。 Next, although it demonstrates further using an Example, this invention is not restrict | limited at all by an Example.

［筒形放射線遮蔽部の作製］
外径５４ｍｍ、内径４４ｍｍおよび長さ１１０ｍｍである筒形形状の一端に、底面外径５４ｍｍ、底面内径４４ｍｍ、先端に内径１０ｍｍの孔を有した高さ２８ｍｍの略円錐形状の底周面を連結した筒形放射線遮蔽部を鉛鋳造により作製した。また、外装カバーとして厚さ１ｍｍのステンレスを加工形成し、筒形放射線遮蔽部に装着した。 [Production of cylindrical radiation shielding part]
Connected to one end of a cylindrical shape with an outer diameter of 54 mm, an inner diameter of 44 mm, and a length of 110 mm, and a bottom surface of a substantially conical shape with a height of 28 mm having a bottom outer diameter of 54 mm, a bottom inner diameter of 44 mm, and a tip with an inner diameter of 10 mm. The cylindrical radiation shielding part was made by lead casting. Further, stainless steel having a thickness of 1 mm was processed and formed as an exterior cover and mounted on a cylindrical radiation shielding part.

［略筒形連結部の作製］
外径１０ｍｍ、内径７ｍｍ、長さ１２ｍｍの筒形形状で、一端に外径１２ｍｍ、幅２ｍｍの鍔を有した略筒形連結部を鉛切削加工により作製した。 [Preparation of a substantially cylindrical connecting part]
A substantially cylindrical connecting portion having a cylindrical shape with an outer diameter of 10 mm, an inner diameter of 7 mm, and a length of 12 mm and having a flange with an outer diameter of 12 mm and a width of 2 mm at one end was produced by lead cutting.

［放射線検出装置の性能試験］
センチネルリンパ節診断で、投与部位とセンチネルリンパ節とに集積する実際の放射能量の線源を放射性物質である９９ｍＴｃで作製した。投与部位の放射能量は３７ＭＢｑ（投与部位線源）、センチネルリンパ節の放射能量は投与部位放射能量の約１／１００、即ち３７０ＫＢｑ（センチネルリンパ節線源）に調整し、各線源をアクリル製バイアルに封入した。
次に投与部位線源とセンチネルリンパ節線源との距離を５ｃｍに固定した測定用ユニットを作製し、以下の試験に使用した。
尚、試験には前記で作製した筒形放射線遮蔽部および略筒形連結部と放射線測定器（アロカ製／ＴＣＳ−１６１）で構成された本発明放射線検出装置を使用した。 [Performance test of radiation detector]
In the sentinel lymph node diagnosis, the radiation source of the actual amount of radioactivity accumulated at the administration site and the sentinel lymph node was produced with 99mTc which is a radioactive substance. The radioactivity at the administration site is adjusted to 37 MBq (administration site radiation source), the radioactivity at the sentinel lymph node is adjusted to about 1/100 of the radioactivity at the administration site, ie 370 KBq (sentinel lymph node radiation source), and each radiation source is an acrylic vial. Sealed in.
Next, a measurement unit in which the distance between the administration site radiation source and the sentinel lymph node radiation source was fixed to 5 cm was prepared and used for the following tests.
In the test, the radiation detection apparatus of the present invention composed of the cylindrical radiation shielding part and the substantially cylindrical connection part prepared above and a radiation measuring instrument (manufactured by Aroka / TCS-161) was used.

初めに本発明放射線検出装置を机上に固定して設置した。次に、略筒形連結部正面より前方に何も置かない状態でバックグラウンドの放射能量を測定した。
次に図４の本発明放射線検出装置の性能試験説明図に示すように、略筒形連結部１２の正面より前方２ｃｍ離れた位置に測定用ユニット２２を配置した。
次にセンチネルリンパ節線源２１の外側１ｃｍに当るＡ位置より放射能量の測定を行い、矢印方向に測定用ユニットを１ｃｍづつ順次移動させ、ＢからＨの位置で放射能量の測定を行った。測定結果を図５に示す。 First, the radiation detection apparatus of the present invention was fixed on a desk and installed. Next, the amount of radioactivity in the background was measured in a state where nothing was placed in front of the front surface of the substantially cylindrical connecting part.
Next, as shown in the performance test explanatory diagram of the radiation detection apparatus of the present invention in FIG. 4, the measurement unit 22 was arranged at a position 2 cm ahead of the front surface of the substantially cylindrical connecting portion 12.
Next, the amount of radioactivity was measured from the position A corresponding to 1 cm outside the sentinel lymph node source 21, the measurement unit was sequentially moved by 1 cm in the direction of the arrow, and the amount of radioactivity was measured at positions B to H. The measurement results are shown in FIG.

図５より、センチネルリンパ節線源（測定位置Ｂ）の測定値がバックグラウンドに対して２倍以上あり、十分な感度が認められた。更にセンチネルリンパ節線源と投与部位線源（測定位置Ｇ）との間に明確な測定値の低下（測定位置Ｄ：センチネルリンパ節線源の測定値と比較して約６７％減）が確認でき、特異性が認められた。これらの結果より、センチネルリンパ節線源の検出が可能であることが分かる。 From FIG. 5, the measured value of the sentinel lymph node source (measurement position B) was more than twice the background, and sufficient sensitivity was recognized. Furthermore, a clear decrease in measured values (measurement position D: approximately 67% decrease compared to measured values of sentinel lymph node source) is confirmed between the sentinel lymph node source and the administration site source (measurement position G). And specificity was observed. From these results, it can be seen that the sentinel lymph node source can be detected.

本発明放射線検出装置の一部の放射線検出器と放射線遮蔽体の縦断面説明図Longitudinal cross-sectional explanatory drawing of some radiation detectors and radiation shields of the radiation detection apparatus of the present invention 本発明略円錐中空形部の他の形態を示す説明図Explanatory drawing which shows the other form of this invention substantially cone hollow shape part 本発明放射線検出装置を示す説明図Explanatory drawing which shows this invention radiation detection apparatus 本発明放射線検出装置の性能試験説明図Explanatory drawing of performance test of radiation detector of the present invention 本発明放射線検出装置の測定結果を示す説明図Explanatory drawing which shows the measurement result of this invention radiation detection apparatus

符号の説明Explanation of symbols

１：検出部
２：出力部
３：放射線検出器（１＋２）
４：測定部
５：ケーブル
１０：略円錐中空形部
１１：筒形放射線遮蔽部
１２：略筒形連結部
１３：放射線遮蔽体（１１＋１２）
２０：投与部位線源
２１：センチネルリンパ節線源
２２：測定用ユニット 1: Detection unit 2: Output unit 3: Radiation detector (1 + 2)
4: Measuring unit 5: Cable 10: Substantially conical hollow part 11: Cylindrical radiation shielding part 12: Substantially cylindrical connecting part 13: Radiation shielding body (11 + 12)
20: Administration site radiation source 21: Sentinel lymph node radiation source 22: Unit for measurement

Claims (2)

放射線を検出するための検出部を有する放射線検出器と、前記放射線検出器とケーブルで連結され、放射線量を計数率として表示するための測定部とで構成された放射線測定器、
および前記放射線検出器の側面に入射する放射線を遮断するための、一端に略円錐中空形部を有する筒形放射線遮蔽部と、前記略円錐中空形部に連結し放射線の検出特異性を調節するための略筒形連結部とで構成された放射線遮蔽体、
とを備えることを特徴とする放射線検出装置 A radiation detector comprising a radiation detector having a detection unit for detecting radiation, and a measurement unit connected to the radiation detector by a cable and displaying a radiation dose as a counting rate;
And a cylindrical radiation shielding part having a substantially conical hollow part at one end for blocking radiation incident on the side surface of the radiation detector, and adjusting the radiation detection specificity by being connected to the substantially conical hollow part. A radiation shield composed of a substantially cylindrical connecting part for,
A radiation detection apparatus comprising: センチネルリンパ節診断に用いることを特徴とする請求項１に記載の放射線検出装置 The radiation detection apparatus according to claim 1, wherein the radiation detection apparatus is used for diagnosis of a sentinel lymph node.

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