Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Background

Arterial spin-labeling (ASL) imaging is currently the most useful method for diagnosing mitochondrial encephalomyopathy, lactic acidosis, and stroke-like attack syndrome (MELAS). However, ASL is often an optional feature of standard MRI systems. Therefore, not all MRI systems can perform ASL imaging. In contrast, fluid-attenuated inversion recovery (FLAIR) imaging is one of the common sequences in brain MRI because FLAIR imaging can be performed regardless of the specifications of the equipment. This study aimed to compare the diagnostic performance of quantitative analysis of signal intensity obtained from fluid-attenuated inversion recovery (FLAIR) images with ASL images for MELAS with recurrent stroke-like episodes (SLEs). A total of 68 cases with normal magnetic resonance imaging findings and 25 cases diagnosed MELAS with recurrent SLEs were included. We evaluated the frontal lobe and cuneus as target areas and compared the regional cerebral blood flow (rCBF) values obtained from ASL images with the normalized signal intensity (nSI) obtained from FLAIR images.

Results

The sensitivity and specificity for diagnosing MELAS from linear discriminant analysis (LDA) obtained from the rCBF values were 0.84 and 0.941, respectively, and those of nSI were 0.8 and 0.897, respectively. The area under the ROC curves (AUC) calculated from the receiver operating characteristic (ROC) curve analysis using rCBF values and nSI were 0.889 and 0.804, respectively.

Conclusion

Quantitative analysis using the signal intensity of the FLAIR image could have a diagnostic performance equivalent to that of rCBF values obtained from ASL images.

DOI： 10.1186/s43054-023-00232-4

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Other Link： https://link.springer.com/article/10.1186/s43054-023-00232-4/fulltext.html

Language：Japanese   Publisher：(一社)日本コンピュータ外科学会  

著者らは、術者の被ばく量低減を目的として、遠隔操作型のCT透視ガイド下針穿刺ロボット(Zerobot)の研究開発を開始している。今回、動物実験のCT画像をもとに術者である医師がロボットを遠隔操作してブタの体内にある標的に対して穿刺を行う場合に、針と標的との位置関係によってどのように針の軌道修正の作業を行うのか調査した。Zerobotを用いて、X軸、Y軸、Z軸の三つの直動軸で三次元方向の並進運動を行い、針の位置を決定した。A軸、B軸の二つの回転軸で回転運動を行い、針の姿勢を決定した。調査に使用したデータはブタを用いた穿刺精度試験で得られたものであった。ロボットを医師が遠隔操作することによる穿刺において、針が標的に近づくにつれ修正回数は指数的に増加していることが分かった。なお、残りの穿刺深さが約10mmとなるのをピークに、それ以降はA軸とB軸の修正回数は減少し、一方で刺し直し回数が増加している様子が観察された。合計60回の穿刺のうち、A軸の修正は110回、B軸の修正は66回、刺し直しは37回であった。自動穿刺シミュレーションの結果、穿刺経路と針との距離と角度がゼロに収束しており、針先を三次元的な穿刺経路に追従させることができることを確認した。針が標的に近づくにしたがって穿刺速度が減速していることが示された。

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Other Link： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2020&ichushi_jid=J03729&link_issn=&doc_id=20200207210002&doc_link_id=10.5759%2Fjscas.22.14&url=https%3A%2F%2Fdoi.org%2F10.5759%2Fjscas.22.14&type=J-STAGE&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00007_2.gif

Publishing type：Research paper (scientific journal)   Publisher：The Japan Society of Computer Aided Surgery  

DOI： 10.5759/jscas.22.14

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Objectives To evaluate the accuracy of robotic CT-guided out-of-plane needle insertion in phantom and animal experiments. Methods A robotic system (Zerobot), developed at our institution, was used for needle insertion. In the phantom experiment, 12 robotic needle insertions into a phantom at various angles in the XY and YZ planes were performed, and the same insertions were manually performed freehand, as well as guided by a smartphone application (SmartPuncture). Angle errors were compared between the robotic and smartphone-guided manual insertions using Student's t test. In the animal experiment, 6 robotic out-of-plane needle insertions toward targets of 1.0 mm in diameter placed in the kidneys and hip muscles of swine were performed, each with and without adjustment of needle orientation based on reconstructed CT images during insertion. Distance accuracy was calculated as the distance between the needle tip and the target center. Results In the phantom experiment, the mean angle errors of the robotic, freehand manual, and smartphone-guided manual insertions were 0.4 degrees, 7.0 degrees, and 3.7 degrees in the XY plane and 0.6 degrees, 6.3 degrees, and 0.6 degrees in the YZ plane, respectively. Robotic insertions in the XY plane were significantly (p < 0.001) more accurate than smartphone-guided insertions. In the animal experiment, the overall mean distance accuracy of robotic insertions with and without adjustment of needle orientation was 2.5 mm and 5.0 mm, respectively. Conclusion Robotic CT-guided out-of-plane needle insertions were more accurate than smartphone-guided manual insertions in the phantom and were also accurate in the in vivo procedure, particularly with adjustment during insertion.

DOI： 10.1007/s00330-019-06477-1

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PubMed

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Publishing type：Research paper (scientific journal)   Publisher：Okayama Medical Association  

DOI： 10.4044/joma.130.161

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Total pages：xiii, 643p   Language：Japanese

CiNii Books

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Language：English   Publisher：RADIOLOGICAL SOC NORTH AMERICA  

Purpose: To evaluate the accuracy of the remote-controlled robotic computed tomography (CT)-guided needle insertion in phantom and animal experiments.
Materials and Methods: In a phantom experiment, 18 robotic and manual insertions each were performed with 19-gauge needles by using CT fluoroscopic guidance for the evaluation of the equivalence of accuracy of insertion between the two groups with a 1.0-mm margin. Needle insertion time, CT fluoroscopy time, and radiation exposure were compared by using the Student t test. The animal experiments were approved by the institutional animal care and use committee. In the animal experiment, five robotic insertions each were attempted toward targets in the liver, kidneys, lungs, and hip muscle of three swine by using 19-gauge or 17-gauge needles and by using conventional CT guidance. The feasibility, safety, and accuracy of robotic insertion were evaluated.
Results: The mean accuracies of robotic and manual insertion in phantoms were 1.6 and 1.4 mm, respectively. The 95% confidence interval of the mean difference was 20.3 to 0.6 mm. There were no significant differences in needle insertion time, CT fluoroscopy time, or radiation exposure to the phantom between the two methods. Effective dose to the physician during robotic insertion was always 0 mSv, while that during manual insertion was 5.7 mSv on average (P&lt;.001). Robotic insertion was feasible in the animals, with an overall mean accuracy of 3.2 mm and three minor procedure-related complications.
Conclusion: Robotic insertion exhibited equivalent accuracy as manual insertion in phantoms, without radiation exposure to the physician. It was also found to be accurate in an in vivo procedure in animals. (C) RSNA, 2017

DOI： 10.1148/radiol.2017162856

Web of Science

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Type：Visiting lecture

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