1.Carpal Tunnel Syndrome in Patients Undergoing Long-Term Hemodialysis Therapy: Clinical Characteristics and Results of Surgical Treatment.
Hojin PARK ; Dae Sung LEE ; Tae Kyoung YUN ; Duck Sun AHN
Journal of the Korean Society for Surgery of the Hand 2015;20(3):89-95
PURPOSE: Carpal tunnel syndrome (CTS) has become increasingly recognized as a complication of long-term hemodialysis. This study evaluated the clinical characteristics and compared the results of carpal tunnel release for CTS patients with or without hemodialysis. METHODS: We retrospectively reviewed the clinical characteristics and surgical outcomes of 49 chronic hemodialysis patients with 83 CTS hands. Also, 100 patients were selected for the control group. Patient characteristics, accompanying systemic conditions, operative outcomes were compared. RESULTS: In hemodialysis group, the mean age and hemodialysis duration were 59.5+/-10.5 years and 4.1+/-2.5 years, respectively. Of the 83 hands with CTS, 45 (54.2%) had arteriovenous fistulas, while 38 (45.7%) did not (p=0.02). Most (81.6%) of the patients reported symptom improvement after surgical treatment, and the remaining patients (18.4%) reported persistent and recurrent symptoms. Rates of remaining symptoms and reoperations were significantly higher in the CTS patients with hemodialysis group. CONCLUSION: Majority of CTS patients with hemodialysis have much improved after transverse carpal ligament release. However, they showed higher recurrence than idiopathic CTS patients. In recurrent patients, use of the extended carpal tunnel release is effective in symptom relief.
Arteriovenous Fistula
;
Carpal Tunnel Syndrome*
;
Hand
;
Humans
;
Kidney Failure, Chronic
;
Ligaments
;
Recurrence
;
Renal Dialysis*
;
Retrospective Studies
2.Synchronous Intra-Thyroid Paraganglioma with Carotid Body Tumor.
Hojin AHN ; Sungmin PARK ; Chang Hwan CHOI ; Jae Yol LIM
Korean Journal of Otolaryngology - Head and Neck Surgery 2015;58(4):279-283
Paraganglioma is an uncommon and slowly-growing benign neuro-endocrine tumor originating from the extra-adrenal paraganglia. The most common site of head and neck paraganglioma is the carotid body. Paraganglioma of thyroid gland is a rare disease, and is hard to diagnose preoperatively since the pathologic features are similar to thyroid neoplasm, especially to medullary carcinoma. Occasionally, multiple paragangliomas can be found in the body. To our knowledge, there are two cases of synchronous carotid body tumor with thyroid paraganglioma that have been reported to date. We report a case of 34-year-old female with carotid body paraganglioma synchronous with intra-thyroid paragangloma, which was misdiagnosed as papillary thyroid carcinoma in the preoperative evaluation. After the tumors were successfully excised, there were no signs of complications and the patient has survived the 2-year-follow-up period without recurrence.
Adult
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Carcinoma, Medullary
;
Carotid Body
;
Carotid Body Tumor*
;
Female
;
Head
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Humans
;
Neck
;
Paraganglioma*
;
Rare Diseases
;
Recurrence
;
Thyroid Gland
;
Thyroid Neoplasms
3.Numerical Considerations of the Neurologist in Korea for Appropriate Management of Dementia
Ko Woon KIM ; Sang Wuk JEONG ; Suk Won AHN ; Im Seok KOH ; Hojin CHOI
Journal of the Korean Neurological Association 2018;36(3):165-170
As the number of dementia patients increases due to rapid aging, the burden of dementia becomes a big social problem. In response to this, various policies have been introduced in Korea. In particular, as the new policy of national responsibility for dementia care has been implemented in 2017, detailed plans for improving health care and long-term care support for dementia patients and their caregivers have been introduced. The most important thing in carrying out the comprehensive government plan will be securing sufficient the professional health and social care workforce. However, the number of neurologists to play an important role in the management of dementia will be more and more insufficient. Therefore, the need to supply an adequate number of neurologists in Korea should be discussed.
Aging
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Caregivers
;
Delivery of Health Care
;
Dementia
;
Humans
;
Korea
;
Long-Term Care
;
Social Problems
4.Magnetic Resonance Imaging in Neurologic Diseases
Kee Hyun CHANG ; Man Chung HAN ; Chu Wan KIM ; Hojin MYUNG ; Kil Soo CHOI ; Chang Beom AHN ; Chang Hyun OH ; Zang Hee CHO
Journal of the Korean Radiological Society 1985;21(1):17-30
Magrjetic resonance (MR) imagings with 0.15 Tesla resistive magnet developed by Korea Advanced Institute of 5cience were performed in 27 patients with various neurologic diseases and compared with X-ray computed tomography (CT). The purpose óf the paper is to evaluate the image quality, the diagnostic value and limitation, and the optimal pulse sequence of MR imagings with a resistive magnet. The MR images were obtained by using a variety of pulse sequence with spin echo technique includïng saturation recovery, T2-weighted spin echo, and/or inversion recovery with various pulse repetition(TR) and echo delay (TE) times. The M R imaging demonstrated the capability of detecting the lesions shown on CT in all cases and also detected an additional finding in one case (multiple sclerosis) which was not seen on CT. The MR imaging appeared to be more useful than CT in the evaluation of syringomyelia of spinal cord and white matter disease, while it failed to demonstrate small calcific lesion or inflammatory nodule (less than 1 cm) shown on CT and has shown somewhat poor contrast resolution in the case of meningioma. The spatial resolution of saturation recovery images was similar or superior to CT, whereas the contrast resolution of saturation recovery was inferior to CT. While the saturation recovery images have shown false negative findings in 5 patients (19%), the inversion recovery and T2-weighted spin echo have shown consistently positive findings. The inversion recovery and T2-weighted spin echo images demonstrated better contrast discrimination between normal and pathologic conditions than the saturation recovery images, but somewhat poorer spatial resolution. Authors suggest that the MR images of both the saturation recovery with 300/30 and T2-weighted spin echo with 1000/90 be used as a routine procedure and additional iversion recovery of 1300/300/30 sequence as a option if white matter disease is suspected.
Discrimination (Psychology)
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Humans
;
Korea
;
Leukoencephalopathies
;
Magnetic Resonance Imaging
;
Meningioma
;
Spinal Cord
;
Syringomyelia
;
Tomography, X-Ray Computed
5.Machine Learning Prediction for the Recurrence After Electrical Cardioversion of Patients With Persistent Atrial Fibrillation
Soonil KWON ; Eunjung LEE ; Hojin JU ; Hyo-Jeong AHN ; So-Ryoung LEE ; Eue-Keun CHOI ; Jangwon SUH ; Seil OH ; Wonjong RHEE
Korean Circulation Journal 2023;53(10):677-689
Background and Objectives:
There is limited evidence regarding machine-learning prediction for the recurrence of atrial fibrillation (AF) after electrical cardioversion (ECV).This study aimed to predict the recurrence of AF after ECV using machine learning of clinical features and electrocardiograms (ECGs) in persistent AF patients.
Methods:
We analyzed patients who underwent successful ECV for persistent AF. Machine learning was designed to predict patients with 1-month recurrence. Individual 12-lead ECGs were collected before and after ECV. Various clinical features were collected and trained the extreme gradient boost (XGBoost)-based model. Ten-fold cross-validation was used to evaluate the performance of the model. The performance was compared to the C-statistics of the selected clinical features.
Results:
Among 718 patients (mean age 63.5±9.3 years, men 78.8%), AF recurred in 435(60.6%) patients after 1 month. With the XGBoost-based model, the areas under the receiver operating characteristic curves (AUROCs) were 0.57, 0.60, and 0.63 if the model was trained by clinical features, ECGs, and both (the final model), respectively. For the final model, the sensitivity, specificity, and F1-score were 84.7%, 28.2%, and 0.73, respectively. Although the AF duration showed the best predictive performance (AUROC, 0.58) among the clinical features, it was significantly lower than that of the final machine-learning model (p<0.001).Additional training of extended monitoring data of 15-minute single-lead ECG and photoplethysmography in available patients (n=261) did not significantly improve the model’s performance.
Conclusions
Machine learning showed modest performance in predicting AF recurrence after ECV in persistent AF patients, warranting further validation studies.
6.Dosimetry by Using EBT2 Film for Total Skin Electron Beam Therapy (TSET).
Ui Jung HWANG ; Jeong Eun RAH ; Hojin JEONG ; Sung Hwan AHN ; Dong Wook KIM ; Sang Yeob LEE ; Young Gyung LIM ; Myonggeun YOON ; Dong Ho SHIN ; Se Byeong LEE ; Sung Young PARK ; Hong Ryull PYO ; Weon Kuu CHUNG
Korean Journal of Medical Physics 2010;21(1):60-69
For treatment of Total Skin Electron beam Therapy (TSET), measurement of dose at various conditions is need on the contrary to usual radiotherapy. When treating TSET with modified Stanford technique based on linear accelerator, the energy of treatment electron beam, the spatial dose distribution and the actual doses deposited on the surface of the patient were measured by using EBT2. The measured energy of the electron beam was agreed with the value that measured by ionization chamber, and the spatial dose distribution at the patient position and the doses at several point on the patient's skin could be easily measured by EBT2 film. The dose on the patient that was measured by EBT2 film showed good agreement with the data measured simultaneously by TLD. With the results of this study, it was proven that the EBT2 film can be one of the useful dosimeter for TSET.
Electrons
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Humans
;
Particle Accelerators
;
Skin
7.Study on Absorbed Dose Determination of Electron Beam Quality for Cross-calibration with Plane-parallel Ionization Chamber.
Jeong Eun RAH ; Dong Oh SHIN ; So Hyun PARK ; Hojin JEONG ; Ui Jung HWANG ; Sung Hwan AHN ; Young Kyung LIM ; Dong Wook KIM ; Myonggeun YOON ; Dong Ho SHIN ; Se Byeong LEE ; Tae Suk SUH ; Sung Yong PARK
Korean Journal of Medical Physics 2009;20(2):97-105
Absorbed dose to water based protocols recommended that plane-parallel chambers be calibrated against calibrated cylindrical chambers in a high energy electron beam with R50>7 g/cm2 (E> or =16 MeV). However, such high-energy electron beams are not available at all radiotherapy centers. In this study, we are compared the absorbed dose to water determined according to cross-calibration method in a high energy electron beam of 16 MeV and in electron beam energies of 12 MeV below the cross-calibration quality remark. Absorbed dose were performed for PTW 30013, Wellhofer FC65G Farmer type cylindrical chamber and for PTW 34001, Wellhofer PPC40 Roos type plane-parallel chamber. The cylindrical and the plane-parallel chamber to be calibrated are compared by alternately positioning each at reference depth, zref=0.6R50-0.1 in water phantom. The DW of plane-parallel chamber are derived using across-calibration method at high-energy electron beams of 16, 20 MeV. Then a good agreement is obtained the DW of plane-parallel chamber in 12 MeV. The agreement between 20 MeV and 12 MeV are within 0.2% for IAEA TRS-398.
Electrons
;
Water