JP2013215352A5

JP2013215352A5 -

Info

Publication number: JP2013215352A5
Application number: JP2012087745A
Authority: JP
Filing date: 2012-04-06
Publication date: 2015-05-07
Anticipated expiration: 2032-04-06

Description

上記目的を達成するために、本発明に係るＸ線ＣＴ装置は、Ｘ線を照射するＸ線源と、前記Ｘ線を検出し、検出したＸ線量に応じたアナログデータを出力するＸ線検出素子を複数備えたＸ線検出器と、前記Ｘ線検出素子のそれぞれに対応して設けられ、各Ｘ線検出素子から出力される前記アナログデータをデジタルデータに変換して収集するデータ収集素子を、前記Ｘ線検出素子と同数備えたデータ収集装置と、前記Ｘ線検出素子とそれに対応する前記データ収集素子との１対の組み合わせからなる計測素子の故障を検出する故障素子検出部と、を備え、前記故障素子検出部は、前記計測素子毎に、各計測素子のデジタルデータの出力値を含む計測データを用いて、故障判定に用いるための判定計測データを生成し、故障判定の対象となる対象計測素子の周辺に位置する周辺素子の判定計測データに基づいて、前記故障判定に用いる判定基準データを生成し、前記対象計測素子の判定計測データと、前記判定基準データと、の比較結果に基づいて、前記対象計測素子が故障素子であるか否かを判定する、ことを特徴とする。 In order to achieve the above object, an X-ray CT apparatus according to the present invention includes an X-ray source that irradiates X-rays, and an X-ray detection that detects the X-rays and outputs analog data corresponding to the detected X-ray dose. An X-ray detector having a plurality of elements, and a data collection element provided corresponding to each of the X-ray detection elements, for converting the analog data output from each X-ray detection element into digital data and collecting the data a data collecting device having the same number as the X-ray detecting elements, and a failure element detection unit for detecting a failure of the measuring element consisting of a pair combination of said data collection device and the corresponding said X-ray detecting elements The failure element detection unit generates measurement data to be used for failure determination using measurement data including an output value of digital data of each measurement element for each measurement element, Versus Based on determination measurement data of peripheral elements located around the measurement element, determination reference data used for the failure determination is generated, and based on a comparison result between the determination measurement data of the target measurement element and the determination reference data Then, it is determined whether or not the target measurement element is a faulty element.

Claims

An X-ray source that emits X-rays;
An X-ray detector comprising a plurality of X-ray detection elements for detecting the X-ray and outputting analog data corresponding to the detected X-ray dose;
Data provided corresponding to each of the X-ray detection elements and having the same number of data collection elements as the X-ray detection elements for converting the analog data output from each X-ray detection element into digital data and collecting the data A collecting device ;
A failure element detection unit that detects a failure of a measurement element comprising a pair of combinations of the X-ray detection element and the data collection element corresponding to the X-ray detection element;
The failure element detection unit generates, for each measurement element, determination measurement data for use in failure determination using measurement data including an output value of digital data of each measurement element, and a target for failure determination Based on determination measurement data of peripheral elements located around the measurement element, determination reference data used for the failure determination is generated, and based on a comparison result between the determination measurement data of the target measurement element and the determination reference data Determining whether the target measurement element is a faulty element,
An X-ray CT apparatus characterized by that.

The faulty element detection unit determines that the faulty element is present when a comparison result between the determination measurement data and the determination reference data exceeds a predetermined allowable fluctuation rate.
The X-ray CT apparatus according to claim 1.

The faulty element detection unit generates an approximate function based on the measurement data of the peripheral element for the measurement element at the end of the X-ray detector, and the opposite side of the peripheral element across the measurement element Setting an extrapolation element having an output value based on the approximation function, and generating the determination reference data using the output value of the extrapolation element and the output value of the peripheral element,
The X-ray CT apparatus according to claim 1 or 2, wherein

The failure element detection unit is configured to compare the determination measurement data based on the measurement data obtained by irradiating the X-ray and the determination reference data using the measurement data and the measurement data obtained without irradiating the X-ray. Based on the determination measurement data based on and the comparison result of the determination reference data using the determination data, it is determined which of the X-ray detection element or the data collection element included in the failure element is defective,
The X-ray CT apparatus according to any one of claims 1 to 3.

Prior to the determination of the failed element, the failed element detection unit performs pre-processing for increasing the detection accuracy of the failed element.
The X-ray CT apparatus according to claim 1, wherein

The faulty element detection unit corrects an output value change according to an element area of the X-ray detection element for the determination measurement data as the preprocessing.
The X-ray CT apparatus according to claim 5.

The X-ray detector is configured by arranging a plurality of X-ray detection modules including a plurality of the X-ray detection elements,
The faulty element detection unit corrects an output value of an X-ray detection element located at an end of the X-ray detection module as the preprocessing.
The X-ray CT apparatus according to claim 5.

The X-ray detector is configured by arranging a plurality of X-ray detection modules including a plurality of the X-ray detection elements,
The faulty element detection unit generates determination measurement data and determination criterion data using the X-ray detection module unit as the preprocessing, and uses the determination measurement data and determination criterion data using the determination measurement data. It is determined whether or not there is a failure in the X-ray detection module unit.
The X-ray CT apparatus according to claim 5.

The determination reference data is generated using only the determination measurement data of the peripheral element, or is generated using the determination measurement data of the peripheral element and the determination measurement data of the target measurement element.
The X-ray CT apparatus according to claim 1, wherein

The determination measurement data is generated based on measurement data obtained in an arbitrary plurality of views.
The X-ray CT apparatus according to claim 1, wherein