• Journal of Electrical Engineering and Technology
• /
• 제10권5호
• /
• pp.2197-2204
• /
• 2015

In recent years, medical image diagnosis has growing significant momentous in the medicinal field. Brain and lung image of patient are distorted with salt and pepper noise is caused by moving the head and chest during scanning process of patients. Reconstruction of these images is a most significant field of diagnostic evaluation and is produced clearly through techniques such as linear or non-linear filtering. However, restored images are produced with smaller amount of noise reduction in the presence of huge magnitude of salt and pepper noises. To eliminate the high density of salt and pepper noises from the reproduction of images, a new efficient fuzzy based median filtering algorithm with a moderate elapsed time is proposed in this paper. Reproduction image results show enhanced performance for the proposed algorithm over other available noise reduction filtering techniques in terms of peak signal -to -noise ratio (PSNR), mean square error (MSE), root mean square error (RMSE), mean absolute error (MAE), image enhancement factor (IMF) and structural similarity (SSIM) value when tested on different medical images like magnetic resonance imaging (MRI) and computer tomography (CT) scan brain image and CT scan lung image. The introduced algorithm is switching filter that recognize the noise pixels and then corrects them by using median filter with fuzzy two-sided π- membership function for extracting the local information.

• Journal of Multimedia Information System
• /
• 제2권2호
• /
• pp.207-214
• /
• 2015

In this paper, we proposed new software for 3D rendering of MR images in the medical domain using C# wrapper of Visualization Toolkit (VTK) and Microsoft .NET framework. Our objective in developing this software was to provide medical image segmentation, 3D rendering and visualization of hippocampus for diagnosis of Alzheimer disease patients using DICOM Images. Such three dimensional visualization can play an important role in the diagnosis of Alzheimer disease. Segmented images can be used to reconstruct the 3D volume of the hippocampus, and it can be used for the feature extraction, measure the surface area and volume of hippocampus to assist the diagnosis process. This software has been designed with interactive user interfaces and graphic kernels based on Microsoft.NET framework to get benefited from C# programming techniques, in particular to design pattern and rapid application development nature, a preliminary interactive window is functioning by invoking C#, and the kernel of VTK is simultaneously embedded in to the window, where the graphics resources are then allocated. Representation of visualization is through an interactive window so that the data could be rendered according to user's preference.

• Nuclear Engineering and Technology
• /
• 제51권6호
• /
• pp.1610-1615
• /
• 2019

Positron emission tomography (PET)/magnetic resonance (MR) scanning has the advantage of less additional exposure to radiation than does PET/computed tomography (CT). In particular, MR based attenuation correction (MR AC) can greatly affect the image quality of PET and is frequently obtained using various MR sequences. Thus, the purpose of the current study was to quantitatively compare the image quality between MR non-AC (MR NAC) and MR AC in PET images with three MR sequences. Percent image uniformity (PIU), percent contrast recovery (PCR), and percent background variability (PBV) were estimated to evaluate the quality of PET images with MR AC. Based on the results of PIU, 15.2% increase in the average quality was observed for PET images with MR AC than for PET images with MR NAC. In addition, 28.6% and 71.1% improvement in the average results of PCR and PBV respectively, was observed for PET images with MR AC compared with that with MR NAC. Moreover, no significant difference was observed among the average values using three MR sequences. In conclusion, the current study demonstrated that PET with MR AC improved the image quality and can be help diagnosis in all MR sequence cases.

• 감성과학
• /
• 제13권3호
• /
• pp.551-558
• /
• 2010

통증은 매우 복합적이고 다양한 수준의 경험으로 주관적이거나 객관적일 수 있다. 침술은 통증을 치료하기 위한 아주 오래된 방법이며, 경락 이론을 바탕으로 한다. 침의 효과에 대한 임상적 결과들은 수없이 많이 있지만, 그 기능에 대한 과학적인 이해는 부족한 상태이다. 또한, 실생활에서의 통증 유발 원인과 침술을 통한 통증 억제 또는 치료는 그 차이가 매우 크게 느껴진다. 그러나 최근 연구들을 통해 통증과 침술의 관련성이 밝혀지고 있다. 본 논문에서는 최근 급격히 발달하고 있는 뇌영상 기술들(functional magnetic resonance images, 및 positron emission tomography, electroencephalograph, magnetoencephalography)을 간략히 살펴보고, 이들을 이용한 통증 및 침술 연구들을 살펴보고자 한다. 통증과 침술에 관여하는 뇌 영역들을 확인하여, 이 둘의 유사성 및 차이를 비교하고, 뇌영상 기술을 통해 밝혀지는 뇌의 정보처리 과정을 통해 통증과 침술에 대한 이해를 넓히고자 한다.

• 대한의용생체공학회:의공학회지
• /
• 제30권5호
• /
• pp.373-380
• /
• 2009

In general, Independent component analysis (ICA) is a statistical blind source separation technique, used either in spatial or temporal domain. The spatial or temporal ICAs are designed to extract maximally independent sources in respective domains. The underlying sources for spatiotemporal data (sequence of images) can not always be guaranteed to be independent, therefore spatial ICA extracts the maximally independent spatial sources, deteriorating the temporal sources and vice versa. For such data types, spatiotemporal ICA tries to create a balance by simultaneous optimization in both the domains. However, the spatiotemporal ICA suffers the problem of source ambiguity. Recently, constrained ICA (c-ICA) has been proposed which incorporates a priori information to extract the desired source. In this study, we have extended the c-ICA for better analysis of spatiotemporal data. The proposed algorithm, i.e., constrained spatiotemporal ICA (constrained st-ICA), tries to find the desired independent sources in spatial and temporal domains with no source ambiguity. The performance of the proposed algorithm is tested against the conventional spatial and temporal ICAs using simulated data. Furthermore, its performance for the real spatiotemporal data, functional magnetic resonance images (fMRI), is compared with the SPM (conventional fMRI data analysis tool). The functional maps obtained with the proposed algorithm reveal more activity as compared to SPM.

• Journal of Yeungnam Medical Science
• /
• 제4권1호
• /
• pp.1-15
• /
• 1987

Magnetic Resonance (M.R.) is rapidly emerging technique that provides high quality images and potentially provides much more diagnostic information than do conventional imaging modalities. M.R.I. is conceptually quite different from currently used imaging methods. The complex nature of M.R.I. allows a great deal of flexibility in image product ion and available information, and key points are as follows. 1. M.R.I. offers a non-invasive technique with which to gene rate in vivo human images without ionizing radiation and with no known adverse biological effects. 2. Imaging mechanism of M.R.I. is quite different from conventional imaging modality and for more accurate diagnostic application, It is necessary for physician to understand imaging mechanism of M.R.I. 3. M.R. makes available basic chemical parameters that may provide to be useful for diagnostic medical imaging and more specific pathophysiologic information which are not available by alternate techniques. 4. M.R. can be produced by number of different methods. This flexibility allows the imaging technique to be applicated for particular clinical purpose. Multiplanar and three dimensional imaging may extend the imaging process beyond the single section available with current CT. 5. Future directions include efforts to; a. Further development of hard ware b. More fasternning scan time c. Respiratory and cardiac gated imaging d. Imaging of additional nuclei except hydrogen e. Further development of contrast media f. M.R. in vivo spectroscopy g. Real time M.R. imaging.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제40권3호
• /
• pp.140-146
• /
• 2014

Pigmented villonodular synovitis (PVNS) is a benign but locally aggressive and destructive disease originating in the synovial membranes. It is a proliferative disorder of unknown etiology. Involvement of the temporomandibular joint (TMJ) is very rare. Computed tomography clearly reveals areas of lytic bone erosion and sclerosis, and also clearly defines the extent of the tumor which is the focal areas of hyperdensity within the soft-tissue mass. Magnetic resonance images invariably show profound hypointensity on both T1- and T2-weighted sequences due to hemosiderin pigmentation. Additionally, high signal intensity on T2-weighted images may indicate cystic loculation of the joint fluid. This case study describes a rare case of PVNS of the TMJ with bone destruction of the mandibular condyle. Complete surgical excision of the lesion was performed through a preauricular approach with temporal extension. During the 10-year follow-up, two more operations were performed due to local recurrence and the fracture of the reconstruction plate. Total joint reconstruction with Biomet was finally performed, and the absence of disease was confirmed with a biopsy report showing fibrosis with hyalinization and mild inflammation of the excised soft tissue from the old lesion.

• Journal of Korean Neurosurgical Society
• /
• 제30권9호
• /
• pp.1120-1126
• /
• 2001

Objective : The development of magnetic resonance neurography(MRN) has made it possible to produce highresolution images of peripheral nerves themselves, as well as associated intraneural and extraneural lesions. We evaluated the clinical application and utility of high-resolution MRN techniques for the diagnosis and treatment of a variety of peripheral nerve disorder(PND)s. Material and Method : MRN images were obtained using T1-weighted spin echo, T2-weighted fast spin echo with fat suppression, and short tau inversion recovery(STIR) fast spin-echo pulse sequences. Fifteen patients were studied, three with brachial plexus tumors, five with chronic entrapment syndromes, and seven with traumatic peripheral lesions. Ten patients underwent surgery. Results : In MRN with STIR sequences of axial and coronal imagings, signals of the peripheral nerves with various lesions were detected as fairly bright signals and were discerned from signals of the uninvolved nerves. Increased signal with proximal swelling and distal flattening of the median nerve were seen in all patients of carpal tunnel syndrome. Among the eight patients with brachial plexus injury or tumors, T2-weighted MRN showed increased signal intensity in involved roots in five, enhanced mass lesions in three, and traumatic pseudomeningocele in three. Other associated MRI findings were adjacent bony signal change, neuroma, root adhesion and denervated muscle atophy with signal change. Conclusion : MRN with high-resolution imaging can be useful in the preoperative evaluation and surgical planning in patients with peripheral nerve lesions.

• Investigative Magnetic Resonance Imaging
• /
• 제9권1호
• /
• pp.57-61
• /
• 2005

골육종은 주로 장골의 골간단 (metaphysic) 에 생기는 악성도가 매우 높은 종양으로 두개골에는 매우 드물게 생긴다. 저자들은 두개기저부에 생겨 접형골을 파괴시키면서 약 2개월 만에 재발한 골육종 1예를 보고하고자 한다. 두통과 어지러움증 그리고 오른족 볼쪽의 감각이 저하된 28세 남자의 전산화단층촬영과 자기공명영상소견에서 이 종양은 약 3cm 의 크기로 균일하게 조영증강이 잘 되면서 내부에 낭성변화가 동반된 소견을 보였다. 종양은 완전히 절제되었고 한달간의 항암요법을 시행하였다. 약 두 달후에 다시 시행한 자기공명영상 소견에서 처음 수술한 같은 부위에 다시 처음보다 크기가 더 큰 종양이 발견되었고 제 2차 수술후 병리소견에서 처음과 같은 골육종으로 확진되었다.

• 대한수의학회지
• /
• 제44권2호
• /
• pp.311-315
• /
• 2004

The detection of lymph node metastasis is an important step in tumor staging and is significant for therapy planning. It has been challenged to yield an appropriate image with diagnostic methods such as Magnetic Resonance (MR) and Computed Tomography (CT). Though CT has been used widely and accessed easily to show internal organs, it can hardly provide difference between lymph node and adjacent vessel or fat tissue. It has been well established that MR can reveal the subtle discrepancy within soft tissue. This study investigated the suitability of MR lymph node imaging without contrast enhancement by comparison of T1-weighted image (T1WI) and T2- weighted image (T2WI) in ten normal rabbits. According to the pulse sequence optimized from preliminary study, T1-weighted spin-echo (repetition time/echo time=400/12 ms) and T-2 weighted fast spin-echo (repetition time/echo time=3500/84 ms) images covering the hind limbs and pelvic region were acquired at 1.5 T. Two radiologists scrupulously evaluated the MR images in consensus. And signal intensity of lymph nodes was compared with that of adjacent fat. Statistical analysis showed that T1-weighted coronal image visualized the lymph nodes (iliac, superficial inguinal and popliteal lymph nodes) quickly and consistently rather than T2-weighted one. Conclusively, T1WI for evaluation of lymph nodes is moderately better than T2WI and appears to have potential for quick and sufficient mapping of the lymph nodes. In addition, this normal MR image of lymph nodes could be applied to further study for the evaluation of lymphatic system in abscess and tumor bearing animal model.