1.Brain Iron Imaging in Aging and Cognitive Disorders: MRI Approaches
Jinhee JANG ; Junghwa KANG ; Yoonho NAM
Journal of the Korean Radiological Society 2022;83(3):527-537
Iron has a vital role in the human body, including the central nervous system. Increased deposition of iron in the brain has been reported in aging and important neurodegenerative diseases. Owing to the unique magnetic resonance properties of iron, MRI has great potential for in vivo assessment of iron deposition, distribution, and non-invasive quantification. In this paper, we will review the MRI methods for iron assessment and their changes in aging and neurodegenerative diseases, focusing on Alzheimer’s disease. In addition, we will summarize the limitations of current approaches and introduce new areas and MRI methods for iron imaging that are expected in the future.
2.Macrophage Activation Syndrome Presented in a Case of Neonatal Lupus
Chang Min KANG ; Jinwha CHOI ; JungHwa LEE
Neonatal Medicine 2021;28(3):139-142
Macrophage activation syndrome (MAS) is a potentially life-threatening complication in many autoimmune diseases. Early recognition and intervention are essential for a favorable outcome. Neonatal lupus, an acquired autoimmune disease in neonates caused by the transplacental passage of maternal autoantibodies, is rare and usually self-limited. Herein, we report a case of MAS in a patient with neonatal lupus, which improved with intravenous immunoglobulin.
3.Macrophage Activation Syndrome Presented in a Case of Neonatal Lupus
Chang Min KANG ; Jinwha CHOI ; JungHwa LEE
Neonatal Medicine 2021;28(3):139-142
Macrophage activation syndrome (MAS) is a potentially life-threatening complication in many autoimmune diseases. Early recognition and intervention are essential for a favorable outcome. Neonatal lupus, an acquired autoimmune disease in neonates caused by the transplacental passage of maternal autoantibodies, is rare and usually self-limited. Herein, we report a case of MAS in a patient with neonatal lupus, which improved with intravenous immunoglobulin.
4.Implant Folding Phenomenon in Cohesive Gel; Diagnosis of Suspected Implant Rupture in MRI Finding.
Junghwa SUNG ; Won June YOON ; So Ra KANG ; Yang Woo KIM
Journal of the Korean Society of Aesthetic Plastic Surgery 2010;16(3):161-166
Since the introduction of the 4th generation silicone gel implants, number of breast augmentation using so-called 'cohesive gel' implants has increased rapidly. Still, implant rupture remains the most annoying complication of breast implant surgery. Recently, magnetic resonance image (MRI) is used as the gold standard in diagnosis of implant rupture. We experienced patients diagnosed as implant rupture with MRI finding, whose implants were found not to be ruptured, but only folded. These patients underwent breast augmentation with cohesive gel and presented to our center with complaint of breast asymmetry and texture-related discomfort. We recommended MRI imaging for diagnosis and the result of radiological diagnosis were 'rupture of implant'. After surgical exploration, we found intact implants without rupture. They were severely folded and fixed with folded form. With our experience, we conclude that cohesive gel implants, due to their more cohesive and form-stable characteristics, sometimes tend to fold and fix in stable folded form and in such cases, MRI image can be similar with the image of ruptured implant. Therefore, in diagnosis of cohesive gel rupture, surgeons should consider both radiologic finding and physical examination carefully before the decision of exploration.
Breast
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Breast Implants
;
Female
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Humans
;
Magnetic Resonance Imaging
;
Magnetic Resonance Spectroscopy
;
Mammaplasty
;
Physical Examination
;
Rupture
;
Silicone Gels
5.Convolutional Neural Network-Based Automatic Segmentation of Substantia Nigra on Nigrosome and Neuromelanin Sensitive MR Images
Junghwa KANG ; Hyeonha KIM ; Eunjin KIM ; Eunbi KIM ; Hyebin LEE ; Na-young SHIN ; Yoonho NAM
Investigative Magnetic Resonance Imaging 2021;25(3):156-163
Recently, neuromelanin and nigrosome imaging techniques have been developed to evaluate the substantia nigra in Parkinson’s disease. Previous studies have shown potential benefits of quantitative analysis of neuromelanin and nigrosome images in the substantia nigra, although visual assessments have been performed to evaluate structures in most studies. In this study, we investigate the potential of using deep learning based automatic region segmentation techniques for quantitative analysis of the substantia nigra. The deep convolutional neural network was trained to automatically segment substantia nigra regions on 3D nigrosome and neuromelanin sensitive MR images obtained from 30 subjects. With a 5-fold cross-validation, the mean calculated dice similarity coefficient between manual and deep learning was 0.70 ± 0.11. Although calculated dice similarity coefficients were relatively low due to empirically drawn margins, selected slices were overlapped for more than two slices of all subjects. Our results demonstrate that deep convolutional neural network-based method could provide reliable localization of substantia nigra regions on neuromelanin and nigrosome sensitive MR images.
6.Convolutional Neural Network-Based Automatic Segmentation of Substantia Nigra on Nigrosome and Neuromelanin Sensitive MR Images
Junghwa KANG ; Hyeonha KIM ; Eunjin KIM ; Eunbi KIM ; Hyebin LEE ; Na-young SHIN ; Yoonho NAM
Investigative Magnetic Resonance Imaging 2021;25(3):156-163
Recently, neuromelanin and nigrosome imaging techniques have been developed to evaluate the substantia nigra in Parkinson’s disease. Previous studies have shown potential benefits of quantitative analysis of neuromelanin and nigrosome images in the substantia nigra, although visual assessments have been performed to evaluate structures in most studies. In this study, we investigate the potential of using deep learning based automatic region segmentation techniques for quantitative analysis of the substantia nigra. The deep convolutional neural network was trained to automatically segment substantia nigra regions on 3D nigrosome and neuromelanin sensitive MR images obtained from 30 subjects. With a 5-fold cross-validation, the mean calculated dice similarity coefficient between manual and deep learning was 0.70 ± 0.11. Although calculated dice similarity coefficients were relatively low due to empirically drawn margins, selected slices were overlapped for more than two slices of all subjects. Our results demonstrate that deep convolutional neural network-based method could provide reliable localization of substantia nigra regions on neuromelanin and nigrosome sensitive MR images.
7.Intravenous Fluid Selection for Unruptured Intracranial Aneurysm Clipping : Balanced Crystalloid versus Normal Saline
Jian KANG ; Young Joo SONG ; Sujeong JEON ; Junghwa LEE ; Eunsook LEE ; Ju-Yeun LEE ; Euni LEE ; Jae Seung BANG ; Si Un LEE ; Moon-Ku HAN ; Chang Wan OH ; Tackeun KIM
Journal of Korean Neurosurgical Society 2021;64(4):534-542
Objective:
: While balanced crystalloid (BC) could be a relevant fluid regimen with buffer system compared with normal saline (NS), there have been no studies on the optimal fluid for surgery of an unruptured intracranial aneurysm (UIA). This study aimed to compare the effects of fluid regimens between NS and BC on the metabolic and clinical outcomes of patients who underwent surgery for UIA.
Methods:
: This study was designed as a propensity score matched retrospective comparative study and included adult patients who underwent UIA clipping. Patient groups were categorized as NS and BC groups based on the types of pre-operative fluid and the amount of fluid administered during surgery. The primary outcomes were defined as electrolyte imbalance and acidosis immediately after surgery. The secondary outcomes were the length of stay in the intensive care unit (ICU) and duration from the end of the operation to extubation.
Results:
: A total of 586 patients were enrolled in this study, with each of 293 patients assigned to the NS and BC groups, respectively. Immediately after surgery, serum chloride levels were significantly higher in the NS group. Compared to the NS group, the BC group had lower incidence rates of acidemia (6.5% vs. 11.6%, p=0.043) and metabolic acidosis (0.7% vs. 4.4%, p=0.007). As compared to NS group, BC group had significantly shorter duration from the end of the operation to extubation (250±824 vs. 122±372 minutes, p=0.016) and length of stay in ICU (1.37±1.11 vs. 1.12±0.61 days, p=0.001). Throughout multivariable analysis, use of BC was found to be significant factor for favorable post-operative results.
Conclusion
: This study showed that the patients who received BC during UIA clipping had lower incidence of metabolic acidosis, earlier extubation and shorter ICU stay compared to those who received NS. Therefore, using BC as a peri-operative fluid can be recommended for patients who undergo surgery for UIA.
8.Clinical Implications of Focal Mineral Deposition in the Globus Pallidus on CT and Quantitative Susceptibility Mapping of MRI
Hyojin KIM ; Jinhee JANG ; Junghwa KANG ; Seungun JANG ; Yoonho NAM ; Yangsean CHOI ; Na-young SHIN ; Kook-Jin AHN ; Bum-soo KIM
Korean Journal of Radiology 2022;23(7):742-751
Objective:
To assess focal mineral deposition in the globus pallidus (GP) by CT and quantitative susceptibility mapping (QSM) of MRI scans and evaluate its clinical significance, particularly cerebrovascular degeneration.
Materials and Methods:
This study included 105 patients (66.1 ± 13.7 years; 40 male and 65 female) who underwent both CT and MRI with available QSM data between January 2017 and December 2019. The presence of focal mineral deposition in the GP on QSM (GPQSM) and CT (GPCT) was assessed visually using a three-point scale. Cerebrovascular risk factors and small vessel disease (SVD) imaging markers were also assessed. The clinical and radiological findings were compared between the different grades of GPQSM and GPCT. The relationship between GP grades and cerebrovascular risk factors and SVD imaging markers was assessed using univariable and multivariable linear regression analyses.
Results:
GPCT and GPQSM were significantly associated (p < 0.001) but were not identical. Higher GPCT and GPQSM grades showed smaller gray matter (p = 0.030 and p = 0.025, respectively) and white matter (p = 0.013 and p = 0.019, respectively) volumes, as well as larger GP volumes (p < 0.001 for both). Among SVD markers, white matter hyperintensity was significantly associated with GPCT (p = 0.006) and brain atrophy was significantly associated with GPQSM (p = 0.032) in at univariable analysis. In multivariable analysis, the normalized volume of the GP was independently positively associated with GPCT (p < 0.001) and GPQSM (p = 0.002), while the normalized volume of the GM was independently negatively associated with GPCT (p = 0.040) and GPQSM (p = 0.035).
Conclusion
Focal mineral deposition in the GP on CT and QSM might be a potential imaging marker of cerebral vascular degeneration. Both were associated with increased GP volume.
9.Intravenous Fluid Selection for Unruptured Intracranial Aneurysm Clipping : Balanced Crystalloid versus Normal Saline
Jian KANG ; Young Joo SONG ; Sujeong JEON ; Junghwa LEE ; Eunsook LEE ; Ju-Yeun LEE ; Euni LEE ; Jae Seung BANG ; Si Un LEE ; Moon-Ku HAN ; Chang Wan OH ; Tackeun KIM
Journal of Korean Neurosurgical Society 2021;64(4):534-542
Objective:
: While balanced crystalloid (BC) could be a relevant fluid regimen with buffer system compared with normal saline (NS), there have been no studies on the optimal fluid for surgery of an unruptured intracranial aneurysm (UIA). This study aimed to compare the effects of fluid regimens between NS and BC on the metabolic and clinical outcomes of patients who underwent surgery for UIA.
Methods:
: This study was designed as a propensity score matched retrospective comparative study and included adult patients who underwent UIA clipping. Patient groups were categorized as NS and BC groups based on the types of pre-operative fluid and the amount of fluid administered during surgery. The primary outcomes were defined as electrolyte imbalance and acidosis immediately after surgery. The secondary outcomes were the length of stay in the intensive care unit (ICU) and duration from the end of the operation to extubation.
Results:
: A total of 586 patients were enrolled in this study, with each of 293 patients assigned to the NS and BC groups, respectively. Immediately after surgery, serum chloride levels were significantly higher in the NS group. Compared to the NS group, the BC group had lower incidence rates of acidemia (6.5% vs. 11.6%, p=0.043) and metabolic acidosis (0.7% vs. 4.4%, p=0.007). As compared to NS group, BC group had significantly shorter duration from the end of the operation to extubation (250±824 vs. 122±372 minutes, p=0.016) and length of stay in ICU (1.37±1.11 vs. 1.12±0.61 days, p=0.001). Throughout multivariable analysis, use of BC was found to be significant factor for favorable post-operative results.
Conclusion
: This study showed that the patients who received BC during UIA clipping had lower incidence of metabolic acidosis, earlier extubation and shorter ICU stay compared to those who received NS. Therefore, using BC as a peri-operative fluid can be recommended for patients who undergo surgery for UIA.
10.Muscle Weakness in a Patient with History of Poliomyelitis: A Differential Diagnosis for Post-polio Syndrome (PPS) and Dermatomyositis.
Sang Hee AN ; Ha Young NA ; Seong Hui KANG ; Soo Youn PARK ; Hyung Min YU ; Chae Ho LEE ; Ji Wan KIM ; Se Woong KWON ; Junghwa LEE ; Hae Rim KIM ; Sang Heon LEE
Journal of Rheumatic Diseases 2014;21(3):147-150
Dermatomyositis (DM) is an idiopathic inflammatory myopathy, characterized by inflammation of the proximal skeletal muscles and typical skin manifestations, which results in symmetric muscle weakness. A 43-year-old man was presented with skin rash and left leg weakness, and he had a history of poliomyelitis. Initially, he was diagnosed as having post-polio syndrome (PPS) due to unilateral muscle weakness and a result of an the electromyography (EMG), which had shown patterns of PPS. After 4 months with conservative therapy for PPS, weakness of bilateral upper arms had developed and skin rashes on his entire body had aggravated and progressed. He was diagnosed as having dermatomyositis, based on elevated muscle enzyme levels, typical skin rashes, and typical EMG findings, which indicated muscle disease. When a patient with previous poliomyelitis has a newly developed muscle weakness or pain, we should consider various possible causes other than PPS.
Adult
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Arm
;
Dermatomyositis*
;
Diagnosis, Differential*
;
Electromyography
;
Exanthema
;
Humans
;
Inflammation
;
Leg
;
Muscle Weakness*
;
Muscle, Skeletal
;
Myositis
;
Poliomyelitis*
;
Postpoliomyelitis Syndrome*
;
Skin Manifestations