1.Use of MAVRIC-SL for metal artifact reduction in postoperative canine stifle MRI
Sojin KIM ; Youngmin KIM ; Jae-Pung HAN ; Sunghoon JEON ; Gonhyung KIM ; Sang-Hwan HYUN ; Dongwoo CHANG ; Namsoon LEE
Journal of Veterinary Science 2026;27(2):e21-
Objective:
This study aimed to determine whether a multiacquisition variable-resonance image combination-selective (MAVRIC-SL) sequence, which reduces susceptibility artifacts, is useful for postoperative evaluation.
Methods:
MRI was performed on four dogs that underwent CCLR correction using metallic implants. Imaging was performed with MAVRIC-SL and two-dimensional fast spin echo (2D-FSE) sequences, including proton density (PD), PD fat-suppressed (F/S), and T2-weighted F/S. The artifact area for each sequence was quantitatively analyzed. A four-level qualitative image analysis was performed to assess image artifacts, cartilage delineation, and visualization of the cranial cruciate ligament and bone.
Results:
The artifact area was significantly reduced with MAVRIC-SL than with 2D-FSE, regardless of the metal materials used. In addition, the amount of artifact, cartilage delineation, and visualization of the bone were significantly improved with MAVRIC-SL compared with 2D-FSE.
Conclusions
and Relevance: In this preliminary study, the MAVRIC-SL sequence improves postoperative MRI evaluation by reducing susceptibility artifacts in dogs with CCLR treated with metallic implants.
2.Myelopathy secondary to generalized thoracic caudal articular process aplasia in a non-brachycephalic breed dog: a case report
Youngmin KIM ; Byoungho AN ; Gonhyung KIM ; Dongwoo CHANG ; Namsoon LEE
Korean Journal of Veterinary Research 2025;65(4):e25-
A 5-month-old mixed-breed dog was presented with progressive ambulatory paraparesis. Neurological examination was consistent with thoracolumbar myelopathy. Magnetic resonance imaging (MRI) revealed a spinal (sub)arachnoid diverticulum (SAD) at T8–T9 with spinal cord compression associated with central canal dilation and intramedullary edema. Computed tomography (CT) showed generalized caudal articular process dysplasia (CAPD) from T2 to T9 vertebras. Considering diagnostic imaging results, symptoms were strongly suspected to be due to spinal cord compression associated with CAPD-induced SAD. Surgery was performed and cystic structure was detached. One month after the surgery, no progression of clinical symptoms was observed. To the best of our knowledge, this is the first reported case of SAD causing thoracolumbar myelopathy in a non-brachycephalic dog with generalized CAPD. These findings highlight the potential role of CAPD as a contributing factor to SAD formation. A combination of CT and MRI is recommended for thorough evaluation of vertebral structures and alignment in similar cases.
3.Evaluation of a Curtain-Type Radiation Protection Device for Veterinary Interventional Procedures
Minsik CHOI ; Jaepung HAN ; Changgyu LIM ; Jiwoon PARK ; Sojin KIM ; Uhjin KIM ; Jinhwa CHANG ; Dongwoo CHANG ; Namsoon LEE
Journal of Veterinary Clinics 2024;41(3):157-164
The standard radiation protection method in the angiography suite involves the use of a thyroid shield, a lead apron, and lead glasses. However, exposure to substantial amounts of ionizing radiation can cause cataracts, tumors, and skin erythema. A newly developed curtain-type radiation protection device consists of a curtain drape composed of a five-layer bismuth and lead acrylic head-shielding plate, with both bearing an equivalent 0.25 mm lead thickness. In this study, a quality assurance phantom was used as the patient to create radiation scatter from the radiographic source, and an anthropomorphic mannequin phantom was used as the interventionalist to measure the radiation dose at seven different anatomical locations. Thermoluminescent dosimeters were used to measure the radiation dose. The experimental groups consisted of all-sided or one-sided curtain set-ups, the presence or absence of a conventional shielding system, and the orientation of beam irradiation. Consequently, the curtain-type radiation protection device exhibited better radiation protection range and capabilities than conventional radiation protection systems, especially in safeguarding the forehead, eyes, arms, and feet, with minimal radiation exposure.Moreover, the mean shielding ratios of the conventional shielding system and curtain-type radiation protection device were measured at 51.94% and 93.86%, respectively. Additionally, no significant decrease in the radiation protection range or capability was observed, even with changes in the beam orientation or one-sided protection. Compared with a conventional shielding system, the curtain-type radiation protection device decreased radiation exposure doses and improved comfort. Therefore, it is a potential new radiation protection device for veterinary interventional procedures.
4.Diagnostic imaging features of hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia in a cat
Namsoon LEE ; Jihye CHOI ; Junghee YOON
Journal of Veterinary Science 2022;23(3):e42-
A 1-year-old male Persian cat was presented for castration. Liver incarcerated in a peritoneopericardial diaphragmatic hernia (PPDH) was diagnosed through pre-anesthetic tests. Multiple homogeneous hyperechoic nodules in the hepatic parenchyma were identified using ultrasound. The nodules showed decreased attenuation compared with normal hepatic parenchyma, and the herniated hepatic parenchyma showed increased arterial and decreased portal enhancement on computed tomography. From the histopathology, we diagnosed hydropic degeneration with portal fibrosis and myelolipoma. This report presents diagnostic imaging features of hepatic myelolipoma incarcerated in a PPDH in a cat. When perfusion of the hepatic parenchyma is altered, surgical treatment should be considered.
5.Echocardiographic features of indirect Gerbode defect in a cat
Sang Kwon LEE ; Namsoon LEE ; Kyoung Oh CHO ; Mahmoud SOLIMAN ; Munsu YUN ; Jihye CHOI
Korean Journal of Veterinary Research 2019;59(3):161-163
This report describes the echocardiographic features of an indirect Gerbode defect in a young cat. Echocardiography revealed high-velocity, turbulent systolic flow directed from left ventricle to right ventricle through a ventricular septal defect. The flow immediately entered the right atrium through a tricuspid septal leaflet. The indirect-type Gerbode defect was confirmed through necropsy. When a high-velocity turbulent flow in the RA without pulmonary hypertension is observed on echocardiography, Gerbode defect should be considered.
Animals
;
Cats
;
Echocardiography
;
Heart Atria
;
Heart Septal Defects, Ventricular
;
Heart Ventricles
;
Hypertension, Pulmonary
6.Cerebellar maturation ratio of forebrain and brainstem at magnetic resonance imaging in the micropig.
Kang Jae YI ; Jun Young KIM ; Namsoon LEE ; Mihyun CHOI ; Jung Hee YOON ; Min Cheol CHOI
Korean Journal of Veterinary Research 2012;52(2):83-87
The study of pigs as a human disease model has been conducted in neuroscience. But the morphological development of pig brain by using MRI is rare. The purpose of this study is to determine whether cerebellum maintains consistent proportion to other brain regions in aging. Clinically healthy sixteen micropigs, 1, 2, 4, and 8 months were studied. The micropigs were anesthetized with isoflorane. MRI was acquired using a 0.3T system. To figure out development of ratio that allowed identification of normal cerebellum size, we measured the area of the cerebellum, brainstem, and forebrain from the mid-sagittal brain images on T1W. Mid-sagittal cross-sectional area (CSA) of total brain, forebrain, brainstem, and cerebellum were expressed as absolute values and also as percentages which were compared between the four age groups of micropigs for the purpose to define the effect of age on brain morphometry. It was found that there was not a significant difference in the percentage of the brain occupied by an individual region between groups although the absolute CSA differed significantly among age groups. There was no effect of age on the ratio between the cerebellum and total brain in 4 age groups. The normal size of cerebellum changes during brain development maintained a consistent ratio to other brain regions in normal micropigs. The ratio of CSA quantified on the mid-sagittal MR images offers a suitable method to detect presence of cerebellar anomalies in micropigs.
Aging
;
Brain
;
Brain Stem
;
Cerebellum
;
Humans
;
Magnetic Resonance Imaging
;
Magnetic Resonance Spectroscopy
;
Magnetics
;
Magnets
;
Neurosciences
;
Prosencephalon
;
Swine
7.Evaluation of the lateral ventricle using MRI in normal micropigs.
Mihyun CHOI ; Namsoon LEE ; Kangjae YI ; Junyoung KIM ; Mincheol CHOI
Korean Journal of Veterinary Research 2011;51(3):227-231
This study was undertaken to assess the lateral ventricle, which was some portion of brain and related to congenital anomalies, from 1, 2, 4, and 8 months of age in healthy micropigs. They were induced general anesthesia and performed magnetic resonance imaging (MRI) with a 0.3 Tesla magnet. Each age group was evaluated by three subjects such as lateral ventricular volume, ventricular volume ratio and asymmetry. T1 weighted transverse images were acquired for calculation of lateral ventricular and corresponding brain parenchyma areas. The ratio of bilateral ventricle areas used to analyze the asymmetry. The mean ventricular volumes of each month were 676.74 +/- 25.58 mm3 (1 month-old), 630.64 +/- 143.84 mm3 (2 month-old), 992.12 +/- 106.03 mm3 (4 month-old) and 1172.62 +/- 237.57 mm3 (8 month-old), respectively. The ventricular volume ratio was the smallest at 2 month-old and re-increased from that age. The ratio was significantly different between 2 month-old and other age groups (p < 0.05). The value of bilateral area ratio showed within 1.5 in all experimental animals. Consequently the lateral ventricle showed a positive correlation with aging and symmetric shapes in both sides. The developmental pattern of the lateral ventricle provides basic data in micropigs as an experimental animal model for physiological and neurosurgical approach.
Aging
;
Anesthesia, General
;
Animals
;
Brain
;
Humans
;
Lateral Ventricles
;
Magnetic Resonance Imaging
;
Magnets
;
Models, Animal

Result Analysis
Print
Save
E-mail