• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.2
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• pp.130-136
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• 2015

We evaluate the influence of MR contrast agent on positron emission tomography (PET) image using phantom, animal and human studies. Phantom consisted of 15 solutions with the mixture of various concentrations of Gd-based MR contrast agent and fixed activity of [$^{18}F$]FDG. Animal study was performed using rabbit and two kinds of MR contrast agents. After injecting contrast agent, CT or MRI scanning was performed at 1, 2, 5, 10, and 20 minutes. PET image was obtained using clinical PET/CT scan, and attenuation correction was performed using the all CT images. The values of HU, PET activity and MRI intensity were obtained from ROIs in each phantom and organ regions. In clinical study, patients (n=20) with breast cancer underwent sequential acquisitions of early [$^{18}F$]FDG PET/CT, MRI and delayed PET/CT. In phantom study, as the concentration increased, the CT attenuation and PET activity also increased. However, there was no relationship between the PET activity and the concentration in the clinical dose range of contrast agent. In animal study, change of PET activity was not significant at all time point of CT scan both MR contrast agents. There was no significant change of HU between early and delayed CT, except for kidney. Early and delayed SUV in tumor and liver showed significant increase and decrease, respectively (P<0.05). Under the condition of most clinical study (< 0.2 mM), MR contrast agent did not influence on PET image quantitation.

• Journal of Animal Science and Technology
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• v.66 no.1
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• pp.31-56
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• 2024

Pig farming, a vital industry, necessitates proactive measures for early disease detection and crush symptom monitoring to ensure optimum pig health and safety. This review explores advanced thermal sensing technologies and computer vision-based thermal imaging techniques employed for pig disease and piglet crush symptom monitoring on pig farms. Infrared thermography (IRT) is a non-invasive and efficient technology for measuring pig body temperature, providing advantages such as non-destructive, long-distance, and high-sensitivity measurements. Unlike traditional methods, IRT offers a quick and labor-saving approach to acquiring physiological data impacted by environmental temperature, crucial for understanding pig body physiology and metabolism. IRT aids in early disease detection, respiratory health monitoring, and evaluating vaccination effectiveness. Challenges include body surface emissivity variations affecting measurement accuracy. Thermal imaging and deep learning algorithms are used for pig behavior recognition, with the dorsal plane effective for stress detection. Remote health monitoring through thermal imaging, deep learning, and wearable devices facilitates non-invasive assessment of pig health, minimizing medication use. Integration of advanced sensors, thermal imaging, and deep learning shows potential for disease detection and improvement in pig farming, but challenges and ethical considerations must be addressed for successful implementation. This review summarizes the state-of-the-art technologies used in the pig farming industry, including computer vision algorithms such as object detection, image segmentation, and deep learning techniques. It also discusses the benefits and limitations of IRT technology, providing an overview of the current research field. This study provides valuable insights for researchers and farmers regarding IRT application in pig production, highlighting notable approaches and the latest research findings in this field.

• Medical Lasers
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• v.10 no.1
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• pp.1-6
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• 2021

Intravital microscopy is a high-resolution imaging technique based on laser-scanning two-photon and confocal microscopy, which allows dynamic 3D cellular-level imaging of various biological processes in a living animal in vivo. This unique capability allows biomedical researchers to directly verify a hypothesis in a natural in vivo microenvironment at the cellular level in a physiological setting. During the last decade, intravital microscopy has become an indispensable technique in several fields of biomedical sciences such as molecular and cell biology, immunology, neuroscience, developmental, and tumor biology. The most distinct advantage of intravital microscopy is its capability to provide a longitudinal view of disease progression at the cellular-level with repeated intravital imaging of a single animal over time by saving the images after each session.

• Journal of Veterinary Clinics
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• v.40 no.5
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• pp.365-369
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• 2023

Temporomandibular joint (TMJ) ankylosis is a rare disease impairing mandible movement and can either be intra-articular (true) or extra-articular (false). A cat presented with an inability to open its mouth, drooling, and facial asymmetry. Computed tomography (CT) confirmed an extracapsular abnormal TMJ fusion, and a surgical plan was devised based on the CT imaging. Post-surgery, the cat regained mouth mobility (indicating false ankylosis) and showed an improved prognosis. This case of CT-diagnosed and treated feline TMJ false ankylosis underscores the indispensable role of CT in diagnosing and devising surgical strategies for feline TMJ false ankylosis.

• Korean Journal of Veterinary Research
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• v.63 no.3
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• pp.26.1-26.5
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• 2023

Syringobulbia is a rare neurological disorder characterized by a fluid-filled cavity in the brainstem. In this study, clinical signs, features on magnetic resonance imaging (MRI), and the diseases present concurrently with syringobulbia were investigated in 33 small breed dogs. Most dogs (97%) had concurrent syringomyelia, and some dogs (24%) presented with vestibular or cranial nerve symptoms associated with the medulla oblongata. MRIs revealed slit-like, bulbous, and vertical linear shapes of the cavities on T2-weighted hyperintense and T1-weighted hypointense signals similar to the cerebrospinal fluid. Chiari-like malformations were identified in all dogs. This study highlights the association of syringobulbia with syringomyelia and Chiari-like malformations in small breed dogs with or without brainstem-associated clinical signs.

• Molecules and Cells
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• v.23 no.2
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• pp.132-137
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• 2007

With the advance of stem cell transplantation research, in vivo cell tracking techniques have become increasingly important in recent years. Magnetic resonance imaging (MRI) may provide a unique tool for non-invasive tracking of transplanted cells. Since the initial findings on the stem cell migration by MRI several years ago, there have been numerous studies using various animal models, notably in heart or brain disease models. In order to develop more reliable and clinically applicable methodologies, multiple aspects should be taken into consideration. In this review, we will summarize the current status and future perspectives of in vivo cell tracking technologies using MRI. In particular, use of different MR contrast agents and their detection methods using MRI will be described in much detail. In addition, various cell labeling methods to increase the sensitivity of signals will be extensively discussed. We will also review several key experiments, in which MRI techniques were utilized to detect the presence and/or migration of transplanted stem cells in various animal models. Finally, we will discuss the current problems and future directions of cell tracking methods using MRI.

• Journal of Sensor Science and Technology
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• v.26 no.4
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• pp.245-250
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• 2017

A novel method to implement a birdcage-type receiving coil sensor for use in a magnetic resonance imaging(MRI) system has been demonstrated employing a flexible printed circuit board (FPCB) fabrication technique. Unlike the conventional methods, the two-dimensional shape of the coil sensor is first implemented as a FPCB and then it is attached to the surface of a cylindrical supporting structure to implement the three-dimensional birdcage-type coil sensor. The proposed method is very effective to implement object-specific MRI coil sensors especially for small animal measurements in research and preclinical applications since the existing well-developed FPCB-based techniques can easily meet the requirements on accuracies and costs during coil implement process. The performances of the coil sensor verified through $^1H$ 1.5T MRI measurements for small animals and it showed excellent characteristics by providing a high spatial precision and a high signal-to-noise ratio.

• Nuclear Engineering and Technology
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• v.53 no.8
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• pp.2646-2651
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• 2021

A rectangular-shaped PET system with an adjustable gantry (AGPET) has been developed for imaging small animals. The AGPET system employs a new depth of interaction (DOI) method using a depth dependent reflector patterns and a new digital time pickoff method based on the pulse reconstruction method. To evaluate the performance of the AGPET, timing resolution, intrinsic spatial resolution and point source images were acquired. The timing resolution and intrinsic spatial resolution were measured using two detector modules and Na-22 gamma source. The PET images were acquired in two field of view (FOV) sizes, 30 mm and 90 mm, to demonstrate the characteristic of the AGPET. As a result of in the experiment results, the timing resolution was 0.9 ns using the pulse reconstruction method based on the bi-exponential model. The intrinsic spatial resolution was an average of 1.7 mm and the spatial resolution of PET images after DOI correction was 2.08 mm and 2.25 mm at the centers of 30 mm and 90 mm FOV, respectively. The results show that the proposed AGPET system provided higher sensitivity and resolution for small animal imaging.

• Journal of Veterinary Clinics
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• v.31 no.3
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• pp.237-240
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• 2014

A 12-year-old, intact, female Alaskan malamute presented with severe spinal pain and hind limb lameness. On radiographs, a round, demarcated lytic lesion was identified in the central fifth lumbar vertebra. On magnetic resonance imaging (MRI), the lesion involving the spinal cord appeared hypointense on T1 weighted, hyperintense on T2 weighted, heterogeneously enhanced on post-contrast T1 weighted, and hypointense on GE images. A focal, small, ill-defined, lytic lesion was also observed radiographically in the sixth lumbar vertebra, it appeared as a focal hyperintense lesion on T1 weighted, T2 weighted, and GE images and showed focal enhancement on post-contrast T1 weighted images. She was euthanized owing to extreme pain and severe and progressive clinical signs; a plasmacytoma was histopthologically diagnosed. This report presents an unusual type of spinal tumor, plasmacytoma. MRI is a useful modality to evaluate the anatomic location and extension of spinal lesions.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1901-1908
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• 2007

The aim of this series of experiments was to examine the opportunity for application of X-ray computer tomography (CT) in cattle production. Firstly, tissue composition of M. longissimus dorsi (LD) cuts between the $11-13^{th}$ ribs (in Exp 1. between the $9-11^{th}$ ribs), was determined by CT and correlated with tissue composition of intact half carcasses prior to dissection and tissue separation. Altogether, 207 animals of different breeds and genders were used in the study. In Exp. 2 and 3, samples were taken from LD cuts, dissected and chemical composition of muscle homogenates was analysed by conventional procedures. Correlation coefficients were calculated among slaughter records, tissues in whole carcasses and tissue composition of rib samples. Results indicated that tissue composition of rib samples determined by CT closely correlated with tissue composition results by dissection of whole carcasses. The findings revealed that figures obtained by CT correlate well with the dissection results of entire carcasses (meat, bone, fat). Close three-way coefficients of correlation (r = 0.80-0.97) were calculated among rib eye area, volume of cut, pixel-sum of adipose tissue determined by CT and intramuscular fat or adipose tissue in entire carcasses. Estimation of tissue composition of carcasses using equations including only CT-data as independent variables proved to be less reliable in prediction of lean meat and bone in carcass ($R^2 = 0.51-0.86$) than for fat (($R^2 = 0.83-0.89$). However, when cold half carcass weight was also included in the equation, the coefficient of determination exceeded $R^2 = 0.90$. In Exp. 3 tissue composition of rib samples by CT were compared to the results of EUROP carcass classification. Findings revealed that CT analysis has higher predictive value in estimation of actual tissue composition of cattle carcasses than EUROP carcass classification.