Improvement of tracking accuracy and stability by recursive image processing in real-time tumor-tracking radiotherapy system

2012 ◽  
Author(s):  
Naoki Miyamoto ◽  
Kenneth Sutherland ◽  
Ryusuke Suzuki ◽  
Taeko Matsuura ◽  
Chie Toramatsu ◽  
...  
Author(s):  
S.H. Park ◽  
J. Kim ◽  
J.E. Lee ◽  
M.K. Kang ◽  
J.W. Lee ◽  
...  

Algorithms ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 155
Author(s):  
Jang-Hwan Choi ◽  
Sooyeul Lee

In this paper we propose a novel method for tracking the respiratory phase and 3D tumor position in real time during treatment. The method uses planning four-dimensional (4D) computed tomography (CT) obtained through the respiratory phase, and a kV projection taken during treatment. First, digitally rendered radiographs (DRRs) are generated from the 4DCT, and the structural similarity (SSIM) between the DRRs and the kV projection is computed to determine the current respiratory phase and magnitude. The 3D position of the tumor corresponding to the phase and magnitude is estimated using non-rigid registration by utilizing the tumor path segmented in the 4DCT. This method is evaluated using data from six patients with lung cancer and dynamic diaphragm phantom data. The method performs well irrespective of the gantry angle used, i.e., a respiration phase tracking accuracy of 97.2 ± 2.5%, and tumor tracking error in 3D of 0.9 ± 0.4 mm. The phantom study reveals that the DRRs match the actual projections well. The time taken to track the tumor is 400 ± 53 ms. This study demonstrated the feasibility of a technique used to track the respiratory phase and 3D tumor position in real time using kV fluoroscopy acquired from arbitrary angles around the freely breathing patient.


2017 ◽  
Vol 9 (1) ◽  
pp. 33-36
Author(s):  
Valencia Wirawan ◽  
Yustinus Eko Soelistio

Telah banyak penelitian pada citra medis telah diadopsi oleh sebagian besar ilmuwan dan dokter yang dapat membantu dalam mendeteksi gangguan pada mata terutama katarak. Namun, umumnya penelitian tersebut menggunakan citra medis atau digital yang relatif mahal dan sulit didapatkan oleh sebagian orang, dan metode yang rentan akan translasi (pergeseran), serta perubahan ukuran gambar dan bentuk objek. Penelitian ini mengembangkan sebuah metode menggunakan model histogram untuk mengklasifikasi mata katarak dari citra digital dengan (1) format yang lebih umum seperti JPEG dan (2) lebih toleranterhadap translasi dan perubahan ukuran. Metode ini juga mampu bekerja dengan baik menggunakan citra digital dalam citra mata yang tidak tegak lurus terhadap kamera. Metode ini mencapai akurasi 79,03% dalam kondisi bebas dan 88.47% dalam kondisi mata tegak lurus terhadap kamera. Metode ini mempunyai kompleksitas yang rendah sehingga dapat digunakan pada komputer dengan spesifikasi rendah dan sistem yang membutuhkan kecepatan mendekati real-time. Index Terms—Image processing, cataract, classification, histogram


1989 ◽  
Vol 7 (3) ◽  
pp. 363-367 ◽  
Author(s):  
Takaichi Koyama ◽  
Yoichi Takahashi ◽  
Masahiro Kobayashi ◽  
Junichiro Morisawa

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Svenja Ipsen ◽  
Sven Böttger ◽  
Holger Schwegmann ◽  
Floris Ernst

AbstractUltrasound (US) imaging, in contrast to other image guidance techniques, offers the distinct advantage of providing volumetric image data in real-time (4D) without using ionizing radiation. The goal of this study was to perform the first quantitative comparison of three different 4D US systems with fast matrix array probes and real-time data streaming regarding their target tracking accuracy and system latency. Sinusoidal motion of varying amplitudes and frequencies was used to simulate breathing motion with a robotic arm and a static US phantom. US volumes and robot positions were acquired online and stored for retrospective analysis. A template matching approach was used for target localization in the US data. Target motion measured in US was compared to the reference trajectory performed by the robot to determine localization accuracy and system latency. Using the robotic setup, all investigated 4D US systems could detect a moving target with sub-millimeter accuracy. However, especially high system latency increased tracking errors substantially and should be compensated with prediction algorithms for respiratory motion compensation.


Data ◽  
2020 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Ahmed Elmogy ◽  
Hamada Rizk ◽  
Amany M. Sarhan

In data mining, outlier detection is a major challenge as it has an important role in many applications such as medical data, image processing, fraud detection, intrusion detection, and so forth. An extensive variety of clustering based approaches have been developed to detect outliers. However they are by nature time consuming which restrict their utilization with real-time applications. Furthermore, outlier detection requests are handled one at a time, which means that each request is initiated individually with a particular set of parameters. In this paper, the first clustering based outlier detection framework, (On the Fly Clustering Based Outlier Detection (OFCOD)) is presented. OFCOD enables analysts to effectively find out outliers on time with request even within huge datasets. The proposed framework has been tested and evaluated using two real world datasets with different features and applications; one with 699 records, and another with five millions records. The experimental results show that the performance of the proposed framework outperforms other existing approaches while considering several evaluation metrics.


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