Radiation Dose and Image Quality Assessment of the Bolus Timing Method for CT Angiography

ObjectiveDifferent technical and procedural methods have been introduced to develop low radiation dose protocols in neurointerventional examinations. We investigated the feasibility of minimizing radiation exposure dose by simply decreasing the detector dose during cerebral DSA and evaluated the comparative level of image quality using both subjective and objective methods.MethodsIn a prospective study of patients undergoing diagnostic cerebral DSA, randomly selected vertebral arteries (VA) and/or internal carotid arteries and their contralateral equivalent arteries were injected. Detector dose of 3.6 and 1.2 μGy/frame were selected to acquire standard dose (SD) and low dose (LD) images, respectively. Subjective image quality assessment was performed by two neurointerventionalists using a 5 point scale. For objective image quality evaluation, circle of Willis vessels were categorized into conducting, primary, secondary, and side branch vessels. Two blinded observers performed arterial diameter measurements in each category. Only image series obtained from VA injections opacifying the identical posterior intracranial circulation were utilized for objective assessment.ResultsNo significant difference between SD and LD images was observed in subjective and objective image quality assessment in 22 image series obtained from 10 patients. Mean reference air kerma and kerma area product were significantly reduced by 61.28% and 61.24% in the LD protocol, respectively.ConclusionsOur study highlights the necessity for reconsidering radiation dose protocols in neurointerventional procedures, especially at the level of baseline factory settings.

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A Novel Hybrid Image Quality Assessment Algorithm

Indian Journal Of Applied Research ◽

10.15373/2249555x/apr2014/31 ◽

2011 ◽

Vol 4 (4) ◽

pp. 107-108

Author(s):

Deepa Maria Thomas ◽

◽

S. John Livingston

Keyword(s):

Image Quality ◽

Quality Assessment ◽

Image Quality Assessment

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Implementation of No Reference Distortion Patch Features Image Quality Assessment Algorithm Based on Human Visual System

International Journal on Communications Antenna and Propagation (IRECAP) ◽

10.15866/irecap.v4i5.4166 ◽

2014 ◽

Vol 4 (5) ◽

pp. 195

Author(s):

Ch. Subrahmanyam ◽

D. Venkata Rao ◽

N. Usha Rani

Keyword(s):

Image Quality ◽

Visual System ◽

Quality Assessment ◽

Human Visual System ◽

Image Quality Assessment

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Document Image Quality Assessment with Relaying Reference to Determine Minimum Readable Resolution for Compression

Electronic Imaging ◽

10.2352/issn.2470-1173.2020.9.iqsp-323 ◽

2020 ◽

Vol 2020 (9) ◽

pp. 323-1-323-8

Author(s):

Litao Hu ◽

Zhenhua Hu ◽

Peter Bauer ◽

Todd J. Harris ◽

Jan P. Allebach

Keyword(s):

Image Quality ◽

Quality Assessment ◽

Image Quality Assessment ◽

Research Area ◽

Input Image ◽

Quality Score ◽

Document Image ◽

Digital Cameras ◽

Active Research ◽

Traditional Approaches

Image quality assessment has been a very active research area in the field of image processing, and there have been numerous methods proposed. However, most of the existing methods focus on digital images that only or mainly contain pictures or photos taken by digital cameras. Traditional approaches evaluate an input image as a whole and try to estimate a quality score for the image, in order to give viewers an idea of how “good” the image looks. In this paper, we mainly focus on the quality evaluation of contents of symbols like texts, bar-codes, QR-codes, lines, and hand-writings in target images. Estimating a quality score for this kind of information can be based on whether or not it is readable by a human, or recognizable by a decoder. Moreover, we mainly study the viewing quality of the scanned document of a printed image. For this purpose, we propose a novel image quality assessment algorithm that is able to determine the readability of a scanned document or regions in a scanned document. Experimental results on some testing images demonstrate the effectiveness of our method.

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No-Reference Image Quality Assessment Based on Multi-Order Gradients Statistics

Journal of Imaging Science and Technology ◽

10.2352/j.imagingsci.technol.2020.64.1.010505 ◽

2020 ◽

Vol 64 (1) ◽

pp. 10505-1-10505-16

Author(s):

Yin Zhang ◽

Xuehan Bai ◽

Junhua Yan ◽

Yongqi Xiao ◽

C. R. Chatwin ◽

...

Keyword(s):

Neural Network ◽

Image Quality ◽

Quality Assessment ◽

Image Quality Assessment ◽

Assessment Method ◽

Image Distortion ◽

Image Feature ◽

Reference Image ◽

Gradient Magnitude ◽

Distortion Type

Abstract A new blind image quality assessment method called No-Reference Image Quality Assessment Based on Multi-Order Gradients Statistics is proposed, which is aimed at solving the problem that the existing no-reference image quality assessment methods cannot determine the type of image distortion and that the quality evaluation has poor robustness for different types of distortion. In this article, an 18-dimensional image feature vector is constructed from gradient magnitude features, relative gradient orientation features, and relative gradient magnitude features over two scales and three orders on the basis of the relationship between multi-order gradient statistics and the type and degree of image distortion. The feature matrix and distortion types of known distorted images are used to train an AdaBoost_BP neural network to determine the image distortion type; the feature matrix and subjective scores of known distorted images are used to train an AdaBoost_BP neural network to determine the image distortion degree. A series of comparative experiments were carried out using Laboratory of Image and Video Engineering (LIVE), LIVE Multiply Distorted Image Quality, Tampere Image, and Optics Remote Sensing Image databases. Experimental results show that the proposed method has high distortion type judgment accuracy and that the quality score shows good subjective consistency and robustness for all types of distortion. The performance of the proposed method is not constricted to a particular database, and the proposed method has high operational efficiency.

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