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1.
J Digit Imaging ; 36(1): 259-275, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36038701

RESUMO

Storage and transmission of high-compression 3D radiological images that create high-quality reconstruction upon decompression are critical necessities for effective and efficient teleradiology. To cater to this need, we propose a near lossless 3D image volume compression method based on optimal multilinear singular value decomposition called "3D-VOI-OMLSVD." The proposed strategy first eliminates any blank 2D image slices from the 3D image volume and uses the selective bounding volume (SBV) to identify and extract the volume of Interest (VOI). Following this, the VOI is decomposed with an optimal multilinear singular value decomposition (OMLSVD) to obtain the corresponding core tensor, factor matrices, and singular values that are compressed with adaptive binary range coder (ABRC), integrated as an entropy encoder. The compressed file can be transferred or transmitted and then decompressed in order to reconstruct the original image. The resultant decompressed VOI is acquired by reversing the above process and then fusing it with the background, using the bound volume coordinates associated with the compressed 3D image. The proposed method performance was tested on a variety of 3D radiological images with different imaging modalities and dimensions using quantitative evaluation metrics such as the compression rate (CR), bit rate (BR), peak signal to noise ratio (PSNR), and structural similarity index (SSIM). Furthermore, we also investigate the impact of VOI extraction on the model performance, before comparing it with two popular compression methods, namely JPEG and JPEG2000. Our proposed method, 3D-VOI-OMLSVD, displayed a high CR value, with a maximum of 37.31, and a low BR, with the lowest reported to be 0.21. The SSIM score was consistently high, with an average performance of 0.9868, while using < 1 second for decoding the image. We observe that with VOI extraction, the compression rate increases manifold, and bit rate drops significantly, and thus reduces the encoding and decoding time to a great extent. Compared to JPEG and JPEG2000, our method consistently performs better in terms of higher CR and lower BR. The results indicate that the proposed compression methodology performs consistently to create high-quality image compressions, and overall gives a better outcome when compared against two state-of-the-art and widely used methods, JPEG and JPEG2000.


Assuntos
Compressão de Dados , Telerradiologia , Humanos , Compressão de Dados/métodos , Radiografia , Tomografia Computadorizada por Raios X/métodos , Imageamento Tridimensional/métodos , Algoritmos
2.
Arch Comput Methods Eng ; 29(2): 975-1007, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35342283

RESUMO

In this world of big data, the development and exploitation of medical technology is vastly increasing and especially in big biomedical imaging modalities available across medicine. At the same instant, acquisition, processing, storing and transmission of such huge medical data requires efficient and robust data compression models. Over the last two decades, numerous compression mechanisms, techniques and algorithms were proposed by many researchers. This work provides a detailed status of these existing computational compression methods for medical imaging data. Appropriate classification, performance metrics, practical issues and challenges in enhancing the two dimensional (2D) and three dimensional (3D) medical image compression arena are reviewed in detail.

3.
J Digit Imaging ; 29(3): 365-79, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26628083

RESUMO

The high resolution magnetic resonance (MR) brain images contain some non-brain tissues such as skin, fat, muscle, neck, and eye balls compared to the functional images namely positron emission tomography (PET), single photon emission computed tomography (SPECT), and functional magnetic resonance imaging (fMRI) which usually contain relatively less non-brain tissues. The presence of these non-brain tissues is considered as a major obstacle for automatic brain image segmentation and analysis techniques. Therefore, quantitative morphometric studies of MR brain images often require a preliminary processing to isolate the brain from extra-cranial or non-brain tissues, commonly referred to as skull stripping. This paper describes the available methods on skull stripping and an exploratory review of recent literature on the existing skull stripping methods.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Crânio/diagnóstico por imagem , Mapeamento Encefálico , Humanos
4.
J Comput Assist Tomogr ; 37(3): 353-68, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23674005

RESUMO

The high-resolution magnetic resonance brain images often contain some nonbrain tissues (ie, skin, fat, muscle, neck, eye balls, etc) compared with the functional images such as positron emission tomography, single-photon emission computed tomography, and functional magnetic resonance imaging (MRI) scans, which usually contain few nonbrain tissues. Automatic segmentation of brain tissues from MRI scans remains a challenging task due to the variation in shape and size, use of different pulse sequences, overlapping signal intensities and imaging artifacts. This article presents a contour-based automatic brain segmentation method to segment the brain regions from T1-, T2-, and proton density-weighted MRI of human head scans. The proposed method consists of 2 stages. In stage 1, the brain regions in the middle slice is extracted. Many of the existing methods failed to extract brain regions in the lower and upper slices of the brain volume, where the brain appears in more than 1 connected region. To overcome this problem, in the proposed method, a landmark circle is drawn at the center of the extracted brain region of a middle slice and is likely to pass through all the brain regions in the remaining lower and upper slices irrespective of whether the brain is composed of 1 or more connected components. In stage 2, the brain regions in the remaining slices are extracted with reference to the landmark circle obtained in stage 1. The proposed method is robust to the variability of brain anatomy, image orientation, and image type, and it extracts the brain regions accurately in T1-, T2-, and proton density-weighted normal and abnormal brain images. Experimental results by applying the proposed method on 100 volumes of brain images show that the proposed method exhibits best and consistent performance than by the popular existing methods brain extraction tool, brain surface extraction, watershed algorithm, hybrid watershed algorithm, and skull stripping using graph cuts.


Assuntos
Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Algoritmos , Artefatos , Feminino , Humanos , Masculino
5.
Indian J Med Res ; 101: 273-6, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7672839

RESUMO

A 772bp DNA fragment from human beta-globin gene has been amplified by polymerase chain reaction (PCR) and subjected to restriction enzyme analysis using Bsu 361, an isoschizomer of restriction enzyme Mst II. This protocol has been designed basically to enhance the analytical facility for the detection of sickle cell mutation. A 430bp DNA fragment was found to be associated with the mutant locus, whereas 228bp and 202bp DNA fragments were generated from the normal locus. This difference of about 202bp in the resulting fragments from the mutant and normal loci has improved discriminatory power in the genotype analysis of the sickle cell mutation.


Assuntos
Anemia Falciforme/genética , Hemoglobina Falciforme/genética , Anemia Falciforme/diagnóstico , Sequência de Bases , Análise Mutacional de DNA , Desoxirribonucleases de Sítio Específico do Tipo II , Feminino , Globinas/genética , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Gravidez , Diagnóstico Pré-Natal
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