1.Utilization of Magnetic Resonance Imaging in the Diagnosis of Thymic Diseases
Joo Hui KIM ; Jae Ho CHUNG ; Sung Ho HWANG
Investigative Magnetic Resonance Imaging 2025;29(1):31-41
Thymic diseases such as thymic hyperplasia, thymic cysts, thymoma, and thymic carcinoma are common causes of mediastinal masses that present with diverse clinical and radiological features. Magnetic resonance imaging (MRI) is a pivotal tool for evaluating thymic pathologies as it offers superior soft-tissue contrast and has the ability to distinguish between benign and malignant lesions. Thymic MRI protocols include T1- and T2-weighted imaging, diffusion-weighted MRI (DW-MRI) with apparent diffusion coefficient mapping, and contrast-enhanced MRI (CE-MRI), each offering unique diagnostic insights into the composition and behavior of thymic lesions. However, interpreting MRI findings in thymic diseases may present challenges. Thymic cysts containing hemorrhage or proteinaceous material may mimic solid lesions owing to altered signal intensities, necessitating DW-MRI and CE-MRI for accurate differentiation. Small thymic lesions, particularly those <1 cm in diameter, are susceptible to signal distortion and partial volume effects, complicating their detection and characterization. Furthermore, respiratory and cardiac motion artifacts can degrade the image quality and obscure important diagnostic details, especially in lesions near the heart and lungs. Despite these challenges, MRI remains a critical imaging modality for assessing and managing thymic diseases, offering detailed tissue characterization. Interpretive pitfalls and technical limitations underscore the importance of employing optimized imaging protocols and expert analyses to ensure diagnostic accuracy and guide appropriate clinical decision-making.
2.Utilization of Magnetic Resonance Imaging in the Diagnosis of Thymic Diseases
Joo Hui KIM ; Jae Ho CHUNG ; Sung Ho HWANG
Investigative Magnetic Resonance Imaging 2025;29(1):31-41
Thymic diseases such as thymic hyperplasia, thymic cysts, thymoma, and thymic carcinoma are common causes of mediastinal masses that present with diverse clinical and radiological features. Magnetic resonance imaging (MRI) is a pivotal tool for evaluating thymic pathologies as it offers superior soft-tissue contrast and has the ability to distinguish between benign and malignant lesions. Thymic MRI protocols include T1- and T2-weighted imaging, diffusion-weighted MRI (DW-MRI) with apparent diffusion coefficient mapping, and contrast-enhanced MRI (CE-MRI), each offering unique diagnostic insights into the composition and behavior of thymic lesions. However, interpreting MRI findings in thymic diseases may present challenges. Thymic cysts containing hemorrhage or proteinaceous material may mimic solid lesions owing to altered signal intensities, necessitating DW-MRI and CE-MRI for accurate differentiation. Small thymic lesions, particularly those <1 cm in diameter, are susceptible to signal distortion and partial volume effects, complicating their detection and characterization. Furthermore, respiratory and cardiac motion artifacts can degrade the image quality and obscure important diagnostic details, especially in lesions near the heart and lungs. Despite these challenges, MRI remains a critical imaging modality for assessing and managing thymic diseases, offering detailed tissue characterization. Interpretive pitfalls and technical limitations underscore the importance of employing optimized imaging protocols and expert analyses to ensure diagnostic accuracy and guide appropriate clinical decision-making.
3.Utilization of Magnetic Resonance Imaging in the Diagnosis of Thymic Diseases
Joo Hui KIM ; Jae Ho CHUNG ; Sung Ho HWANG
Investigative Magnetic Resonance Imaging 2025;29(1):31-41
Thymic diseases such as thymic hyperplasia, thymic cysts, thymoma, and thymic carcinoma are common causes of mediastinal masses that present with diverse clinical and radiological features. Magnetic resonance imaging (MRI) is a pivotal tool for evaluating thymic pathologies as it offers superior soft-tissue contrast and has the ability to distinguish between benign and malignant lesions. Thymic MRI protocols include T1- and T2-weighted imaging, diffusion-weighted MRI (DW-MRI) with apparent diffusion coefficient mapping, and contrast-enhanced MRI (CE-MRI), each offering unique diagnostic insights into the composition and behavior of thymic lesions. However, interpreting MRI findings in thymic diseases may present challenges. Thymic cysts containing hemorrhage or proteinaceous material may mimic solid lesions owing to altered signal intensities, necessitating DW-MRI and CE-MRI for accurate differentiation. Small thymic lesions, particularly those <1 cm in diameter, are susceptible to signal distortion and partial volume effects, complicating their detection and characterization. Furthermore, respiratory and cardiac motion artifacts can degrade the image quality and obscure important diagnostic details, especially in lesions near the heart and lungs. Despite these challenges, MRI remains a critical imaging modality for assessing and managing thymic diseases, offering detailed tissue characterization. Interpretive pitfalls and technical limitations underscore the importance of employing optimized imaging protocols and expert analyses to ensure diagnostic accuracy and guide appropriate clinical decision-making.
4.Second Toe Transfer for the Thumb Reconstruction.
So Min HWANG ; Sung Min AHN ; Kwang Ryeol LIM ; Yong Hui JUNG ; Min Hee RYU
Journal of the Korean Society for Surgery of the Hand 2009;14(3):95-101
PURPOSE: Thumb is the most important part of the hand. That requires reconstruction as a top priority. The operative methods for thumb reconstruction have been developed variously to the microsurgical technique. For better functional and cosmetic effects of the thumb, many studies and reports on toe transfer for thumb reconstruction have been conducted. Great toe transfer for thumb reconstruction was first reported by Cobbett in 1969. Since then, the second toe transfer also has been reported by Dongyue in 1979. Author report about advantages and disadvantages of the second toe transfer for thumb reconstruction. MATERIALS AND METHODS: The second toe transfer had been conducted transfer for nine patients from March 1998 to February 2007. The patient's age ranged from 18 to 52, averaging 30 years old. The levels of defect were classified as two proximal portion of proximal phalanx,five metacarpo-phalangeal joints, and two distal portion of metacarpal bone. The causes of thumb defect were classified as six trauma, two electrical burn, and one malignant tumor cases. The results were evaluated with sensation and strength the reconstructed thumb, cometic effect of recipient site, aesthetic effects at donor sites, and gait problem, at mean 32 months after the operation. RESULTS: After the second toe transfer, the reconstructed thumb's sense was measured as average 8.2 mm at 2 point discrimination test and it's pinching power measured average 81.7% compared to normal thumbs. The degree of cosmetic satisfaction of both donor & recipient sites appeared at 3.4 and 4.7, respectively. CONCLUSIONS: When choosing an operative method for the thumb reconstruction, we have to consider functional and cosmetic effect as well as the socio-cultural background. If we apply the second toe transfer according to the amputation level of the thumb, it would be a good satisfying operative method.
Amputation
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Burns
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Cosmetics
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Discrimination (Psychology)
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Gait
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Hand
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Humans
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Joints
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Sensation
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Thumb
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Tissue Donors
;
Toes
5.Modified Seven-flap Web Plasty for Incomplete Syndactyly.
So Min HWANG ; Hong Il KIM ; Sung Min AHN ; Kwang Ryeol LIM ; Yong Hui JUNG ; Jennifer K SONG
Journal of the Korean Society for Surgery of the Hand 2012;17(2):53-59
PURPOSE: Incomplete syndactyly, due to either congenital or acquired, is uncommon. Many different surgical methods have been descirbed. We introduce the modification of seven flap-plasty for incomplete syndactyly and report functional improvement after correction by modified seven flap-plasty without skin graft. MATERIALS AND METHODS: Twelve patients with an incomplete syndactyly who underwent modified seven flap-plasty were analyzed. Age ranged from one to 40-year-old (average age 21). There were 8 males and 4 females, and the degree of syndactyly was near proximal interphalangeal joint. Two different operative methods were performed. Modification I modified two half-Z flaps in parallelogram shape, and modification II modified V flap of V-M flap in Y-V flap. Functional improvements was measured by maximal abduction distance and maximal abduction angle change. RESULTS: All cases were corrected by using the modified seven flap plasty. Flap tip necrosis was found in two cases of severe burn scar patients, but did not require additional surgery. There was no specific complications. Maximal abduction distance was increased in 6 mm, and maximal abduction angle was increased in 5.8degrees. CONCLUSION: Incomplete syndactyly near proximal interphalangeal joint was corrected by modified seven flap plasty and was able to get a satisfactory result.
Adult
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Burns
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Cicatrix
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Female
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Humans
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Joints
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Male
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Necrosis
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Skin
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Syndactyly
6.Clinical Manifestation of Primary Headache with Epigastric Pain or Tenderness in Children.
Hui Sung HWANG ; Hye Sun CHOI ; Joong Hyun BIN ; Young Hoon KIM ; In Goo LEE ; Seung Yun CHUNG
Journal of the Korean Child Neurology Society 2008;16(2):169-174
PURPOSE: Population-based studies have shown positive associations between migraine and irritable bowel syndrome, colitis and peptic ulcer and migraine prevalence was higher among patients with dysmotility-like dyspepsia or nausea/vomiting. The aim of this study was to investigate clinical manifestation between primary headache with epigastric pain or tenderness(EPT) and primary headache without EPT. METHODS: We retrospectively reviewed the medical records of 58 patients who were diagnosed primary headache[by ICHD-II(2004)] at Incheon St. Mary Hospital from January, 2006 to December, 2007. Their clinical characteristics such as age, sex, frequency & severity of headache and associated symptoms & signs were analysed. RESULTS: The rate of headache associated with EPT were 36% of migraine cases, 50% of tension-type headache cases, and 100% of unclassified headache cases. Headache with EPT were at a high rate in female. Headache with EPT were more severe than one without EPT. Regulation of behavior, diet and sleep pattern had improved severity of headache in 71% of migraine without EPT and 94% of tension-type headache without EPT, but in 12% of migraine with EPT and 18% of tension-type headache with EPT. Headache disappeared in 64% of migraine with EPT and 53% of tension-type headache by additional regular antiacid medication. CONCLUSION: Our study supports any specific correlation between headache and EPT, but further studies are needed.
Abdominal Pain
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Child
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Colitis
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Diet
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Dyspepsia
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Female
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Gastrointestinal Diseases
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Headache
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Humans
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Irritable Bowel Syndrome
;
Medical Records
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Migraine Disorders
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Nausea
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Peptic Ulcer
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Prevalence
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Retrospective Studies
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Tension-Type Headache
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Vomiting
7.A Study about Effects of Osmotic-Controlled Release Oral Delivery System Methylphenidate on Regional Cerebral Blood Flow in Korean Children with Attention-Deficit Hyperactivity Disorder.
Young Hui YANG ; Jun Won HWANG ; Boong Nyun KIM ; Hyejin KANG ; Jae Sung LEE ; Dong Soo LEE ; Soo Churl CHO
Journal of the Korean Academy of Child and Adolescent Psychiatry 2016;27(1):64-71
OBJECTIVES: The objective of this study was to examine the effects of osmotic-controlled release oral delivery system methylphenidate on changes in regional cerebral blood flow (rCBF) in children with attention-deficit hyperactivity disorder (ADHD) using single photon emission computed tomography (SPECT). METHODS: A total of 26 children with ADHD (21 boys, mean age: 9.2±2.05 years old) were recruited. Each ADHD participant was examined for changes in rCBF using technetium-99m-hexamethylpropylene amine oxime brain SPECT before and after 8 weeks methylphenidate medication. Brain SPECT images of pediatric normal controls were selected retrospectively. SPECT images of ADHD children taken before medication were compared with those of pediatric normal controls and those taken after medication using statistical parametric mapping analysis on a voxel-wise basis. RESULTS: Before methylphenidate medication, significantly decreased rCBF in the cerebellum and increased rCBF in the right precuneus, left anterior cingulate, right postcentral gyrus, right inferior parietal lobule and right precentral gyrus were observed in ADHD children compared to pediatric normal controls (p-value<.0005, uncorrected). After medication, we observed significant hypoperfusion in the left thalamus and left cerebellum compared to pediatric normal controls (p-value<.0005, uncorrected). In the comparison between before medication and after medication, there was significant hyperperfusion in the superior frontal gyrus and middle frontal gyrus and significant hypoperfusion in the right insula, right caudate, right middle frontal gyrus, left subcallosal gyrus, left claustrum, and left superior temporal gyrus after methylphenidate medication (p-value<.0005, uncorrected). CONCLUSION: This study supports dysfunctions of fronto-striatal structures and cerebellum in ADHD. We suggest that methylphenidate may have some effects on the frontal lobe, parietal lobe, and cerebellum in children with ADHD.
Basal Ganglia
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Brain
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Cerebellum
;
Child*
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Frontal Lobe
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Humans
;
Methylphenidate*
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Parietal Lobe
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Rabeprazole
;
Retrospective Studies
;
Thalamus
;
Tomography, Emission-Computed, Single-Photon
8.Efficacy of Dextranomer/Hyaluronic Acid Copolymer (Deflux(R)) Injection for Vesicoureteral Reflux in Children.
Suk Jin HONG ; Hyun Hee HWANG ; Eun Hui HONG ; Min Hyun CHO ; Sung Kwang CHUNG
Journal of the Korean Society of Pediatric Nephrology 2009;13(2):229-234
PURPOSE: The aim of this study was evaluating the efficacy of endoscopic Deflux(R) submucosal injection in children with primary vesicoureteral reflux (VUR). METHODS: Retrospective analysis of medical record was conducted on 38 children (59 ureters) who underwent endoscopic Deflux(R) injection due to primary VUR. Data were collected from March 2000 to February 2006. Mean infused amount of Deflux(R) was 0.77 cc. After Deflux(R) injection, patients were reassessed by voiding cystourethrogram (VCUG) 6 months later. RESULTS: The success rate of endoscopic Deflux(R) submucosal injection 6 months later by VCUG was 100% for grade 1 VUR, 87.5% for grade 2, 60% for grade 3, 26.6% for grade 4, 16.6% for grade 5, respectively and there was negatively significant correlation between success rate and grade of VUR (P<0.01). Degree of improvement of VUR by endoscopic Deflux(R) submucosal injection was not related to age at diagnosis, time to operation, existence of voiding dysfunction or constipation and infused amount of Deflux(R). However, group with anticholinergics medication had significantly lower success rate than non-medication group (P<0.047). CONCLUSION: Endoscopic Deflux(R) submucosal injection is effective therapy in patient with primary VUR, especially low grade VUR. It can be not only a useful substitute for prophylaxis with antibiotics, but also an effective management prior to ureteroneocystostomy in children with primary VUR.
Anti-Bacterial Agents
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Child
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Cholinergic Antagonists
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Constipation
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Humans
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Medical Records
;
Retrospective Studies
;
Vesico-Ureteral Reflux
9.Myositis Ossificans on the Nasal Dorsum: A Case Report.
Jennifer K SONG ; So Min HWANG ; Kwang Ryeol LIM ; Yong Hui JUNG ; Sung Min AHN
Journal of the Korean Society of Plastic and Reconstructive Surgeons 2011;38(1):69-72
PURPOSE: Myositis ossificans is a benign condition of heterotopic bone formation that still requires more of its pathologic explanation. The lesions are localized predominantly to the high-risk sites of injury, involving flexor muscles of the upper limbs and thigh, but rarely in the head and neck area. METHODS: A case of a 44-year-old male patient presented with a palpable hard mass on nasal dorsum. The patient experienced a similar lesion on upper limb few years ago. On computed tomographic image, the lesion presented focal definite increase in opacity compatible to adjacent bone densitiy on nasal dorsum. RESULTS: The lesion was excised under open rhinoplasty incision. The pathologic report revealed focal bone formation and calcification within skeletal muscle. CONCLUSION: We describe a unique and only case of a myositis ossificans on nasal dorsum which is indifferent from previous concept.
Adult
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Head
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Humans
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Male
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Muscles
;
Myositis
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Myositis Ossificans
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Neck
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Nose
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Osteogenesis
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Rhinoplasty
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Thigh
;
Upper Extremity
10.Multiple Epidermal Inclusion Cysts in Previous Bone Graft Site of the Thumb: A Case Report.
So Min HWANG ; Hong Il KIM ; Sung Min AHN ; Kwang Ryeol LIM ; Yong Hui JUNG ; Jennifer K SONG
Journal of the Korean Society for Surgery of the Hand 2011;16(4):247-250
We report a 71-year-old male presenting with painful growing mass on his left thumb. The patient had received iliac bone graft on his left thumb 20 years ago, and removed all the grafted bone 8 years ago due to recurrent ulcer. Biopsy revealed multiple eidermal inclusion cysts on the dorsal surface of the bone graft site. Surgeon should be aware of epidermal inclusion cyst occurred at the previous bone graft site of the finger.
Aged
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Biopsy
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Fingers
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Humans
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Male
;
Thumb
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Transplants
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Ulcer