1.The Congruity between the Optical Center of Spectacles and Pupillary Center.
Journal of the Korean Ophthalmological Society 1999;40(4):1090-1093
This study was performed to survey the congruities between the optical centers and pupillary centers and to bring out the optical health in Korea. One hundred outpatient were enrolled in this study, whose visual acuities were better than 20/40 with their glasses. We investigated the difference between interpupillary and interoptical center distance, the horizontal and vertical balance of optical centers, and the relation between optical decentering and dizziness. Thirty-six percent of spectacles were revealed to have inappropriate optical centers. In 25(69%) of 36 inappropriate spectacles, the difference between interpupillary distances and interoptical distances was over 4.0mm. In 7(47%) of 15 patients who complained of dizziness, optical centers were decentered. A large number of patients were wearing the optically decentered spectacles. The patients who complain of dizziness are needed to have the position of the optical centers of their spectacles checked.
Dizziness
;
Eyeglasses*
;
Glass
;
Humans
;
Korea
;
Outpatients
;
Visual Acuity
2.The Congruity between the Optical Center of Spectacles and Pupillary Center.
Journal of the Korean Ophthalmological Society 1999;40(4):1090-1093
This study was performed to survey the congruities between the optical centers and pupillary centers and to bring out the optical health in Korea. One hundred outpatient were enrolled in this study, whose visual acuities were better than 20/40 with their glasses. We investigated the difference between interpupillary and interoptical center distance, the horizontal and vertical balance of optical centers, and the relation between optical decentering and dizziness. Thirty-six percent of spectacles were revealed to have inappropriate optical centers. In 25(69%) of 36 inappropriate spectacles, the difference between interpupillary distances and interoptical distances was over 4.0mm. In 7(47%) of 15 patients who complained of dizziness, optical centers were decentered. A large number of patients were wearing the optically decentered spectacles. The patients who complain of dizziness are needed to have the position of the optical centers of their spectacles checked.
Dizziness
;
Eyeglasses*
;
Glass
;
Humans
;
Korea
;
Outpatients
;
Visual Acuity
3.Unusual Suicide with Chainsaw: An Autopsy Case Report
Yonghan JUNG ; Seonjung JANG ; Hyejin PARK ; Sookyoung LEE
Korean Journal of Legal Medicine 2020;44(1):41-44
In autopsy practice, we encounter case of suicide or murder using various methods or tools. Damage caused by tools such as a knife or hammer is commonly encountered, but a case of damage using a chainsaw is not commonly encountered. We present an autopsy case of a suicide due to neck injury using a chainsaw. A 56-year-old man was found dead with a neck injury and a chainsaw below him. Soft tissue of the neck, thyroid cartilage, trachea, carotid vessels, cervical vertebrae, and cervical spinal cord were found to be cleaved, and a cogwheel-shaped pattern was observed in the injured area.
4.Unusual Suicide with Chainsaw: An Autopsy Case Report
Yonghan JUNG ; Seonjung JANG ; Hyejin PARK ; Sookyoung LEE
Korean Journal of Legal Medicine 2020;44(1):41-44
In autopsy practice, we encounter case of suicide or murder using various methods or tools. Damage caused by tools such as a knife or hammer is commonly encountered, but a case of damage using a chainsaw is not commonly encountered. We present an autopsy case of a suicide due to neck injury using a chainsaw. A 56-year-old man was found dead with a neck injury and a chainsaw below him. Soft tissue of the neck, thyroid cartilage, trachea, carotid vessels, cervical vertebrae, and cervical spinal cord were found to be cleaved, and a cogwheel-shaped pattern was observed in the injured area.
5.Suicide Using an Air Blow Gun
DaeYoil KIM ; JeongMok KIM ; SoJin KIM ; YongHan JUNG ; SangHan LEE
Korean Journal of Legal Medicine 2021;45(1):34-38
An air blow gun is one of the most common pneumatic tools found at industrial sites and entrances of mountain trails in South Korea. It is used for spraying high-pressure air to dust off surfaces and clothes, and to inject air into tubes. There have been many reported cases of injuries and deaths associated with air blow guns. The victim died by placing the nozzle of an air blow gun, installed on an outdoor sports field, into her nose, and pulling the trigger. An autopsy ascribed her death to pneumothorax. Numerous accidents associated with air blow guns have been reported in the media. However, the use of an air blow gun has not been the subject of a suicide case study in forensic literature. To our knowledge, this is the first case report on suicide using an air blow gun. Stronger public safety warnings stressing the potentially fatal outcomes from careless usage of air blow guns are required.
6.High Resolution 3D Magnetic Resonance Fingerprinting with Hybrid Radial-Interleaved EPI Acquisition for Knee Cartilage T1 , T2 Mapping
Dongyeob HAN ; Taehwa HONG ; Yonghan LEE ; Dong-Hyun KIM
Investigative Magnetic Resonance Imaging 2021;25(3):141-155
Purpose:
To develop a 3D magnetic resonance fingerprinting (MRF) method for application in high resolution knee cartilage PD, T1 , T2 mapping.
Materials and Methods:
A novel 3D acquisition trajectory with golden-angle rotating radial in kxy direction and interleaved echo planar imaging (EPI) acquisition in the kz direction was implemented in the MRF framework. A centric order was applied to the interleaved EPI acquisition to reduce Nyquist ghosting artifact due to field inhomogeneity. For the reconstruction, singular value decomposition (SVD) compression method was used to accelerate reconstruction time and conjugate gradient sensitivity-encoding (CG-SENSE) was performed to overcome low SNR of the high resolution data. Phantom experiments were performed to verify the proposed method. In vivo experiments were performed on 6 healthy volunteers and 2 early osteoarthritis (OA) patients.
Results:
In the phantom experiments, the T1 and T2 values of the proposed method were in good agreement with the spin-echo references. The results from the in vivo scans showed high quality proton density (PD), T1 , T2 map with EPI echo train length (NETL = 4), acceleration factor in through plane (Rz = 5), and number of radial spokes (Nspk = 4). In patients, high T2 values (50-60 ms) were seen in all transverse, sagittal, and coronal views and the damaged cartilage regions were in agreement with the hyper-intensity regions shown on conventional turbo spin-echo (TSE) images.
Conclusion
The proposed 3D MRF method can acquire high resolution (0.5 mm3 ) quantitative maps in practical scan time (~ 7 min and 10 sec) with full coverage of the knee (FOV: 160 × 160 × 120 mm3 ).
7.Unusual Suicide with Chainsaw: An Autopsy Case Report
Yonghan JUNG ; Seonjung JANG ; Hyejin PARK ; Sookyoung LEE
Korean Journal of Legal Medicine 2020;44(1):41-44
In autopsy practice, we encounter case of suicide or murder using various methods or tools. Damage caused by tools such as a knife or hammer is commonly encountered, but a case of damage using a chainsaw is not commonly encountered. We present an autopsy case of a suicide due to neck injury using a chainsaw. A 56-year-old man was found dead with a neck injury and a chainsaw below him. Soft tissue of the neck, thyroid cartilage, trachea, carotid vessels, cervical vertebrae, and cervical spinal cord were found to be cleaved, and a cogwheel-shaped pattern was observed in the injured area.
8.High Resolution 3D Magnetic Resonance Fingerprinting with Hybrid Radial-Interleaved EPI Acquisition for Knee Cartilage T1 , T2 Mapping
Dongyeob HAN ; Taehwa HONG ; Yonghan LEE ; Dong-Hyun KIM
Investigative Magnetic Resonance Imaging 2021;25(3):141-155
Purpose:
To develop a 3D magnetic resonance fingerprinting (MRF) method for application in high resolution knee cartilage PD, T1 , T2 mapping.
Materials and Methods:
A novel 3D acquisition trajectory with golden-angle rotating radial in kxy direction and interleaved echo planar imaging (EPI) acquisition in the kz direction was implemented in the MRF framework. A centric order was applied to the interleaved EPI acquisition to reduce Nyquist ghosting artifact due to field inhomogeneity. For the reconstruction, singular value decomposition (SVD) compression method was used to accelerate reconstruction time and conjugate gradient sensitivity-encoding (CG-SENSE) was performed to overcome low SNR of the high resolution data. Phantom experiments were performed to verify the proposed method. In vivo experiments were performed on 6 healthy volunteers and 2 early osteoarthritis (OA) patients.
Results:
In the phantom experiments, the T1 and T2 values of the proposed method were in good agreement with the spin-echo references. The results from the in vivo scans showed high quality proton density (PD), T1 , T2 map with EPI echo train length (NETL = 4), acceleration factor in through plane (Rz = 5), and number of radial spokes (Nspk = 4). In patients, high T2 values (50-60 ms) were seen in all transverse, sagittal, and coronal views and the damaged cartilage regions were in agreement with the hyper-intensity regions shown on conventional turbo spin-echo (TSE) images.
Conclusion
The proposed 3D MRF method can acquire high resolution (0.5 mm3 ) quantitative maps in practical scan time (~ 7 min and 10 sec) with full coverage of the knee (FOV: 160 × 160 × 120 mm3 ).
9.Pathophysiology and Treatment of Gout Arthritis;including Gout Arthritis of Hip Joint: A Literature Review
Yonghan CHA ; Jongwon LEE ; Wonsik CHOY ; Jae Sun LEE ; Hyun Hee LEE ; Dong-Sik CHAE
Hip & Pelvis 2024;36(1):1-11
Gout is triggered by the accumulation of uric acid in the body, leading to hyperuricemia. Genetic, metabolic, and environmental factors can influence this condition. Excessive uric acid buildup results in the formation of monosodium urate (MSU) crystals, which precipitate in specific areas of the body, including the joints, where they can cause symptoms of gout. While the acute and chronic symptoms of gout have been well-documented, diagnosis of gout affecting the hip joint poses significant challenges. The global incidence of gout, the most prevalent form of inflammatory arthritis, is on the rise. Evaluation of the clinical signs, laboratory results, and imaging results is generally required for diagnosis of gout in cases where MSU crystals have not been detected. Hyperuricemia is considered a primary cause of arthritis symptoms, and comprehensive guidelines for treatment are available. Therefore, the choice of medication is straightforward, and moderate effectiveness of treatment has been demonstrated. Gout is a chronic disease, requiring lifelong uric acid-lowering medications, thus application of a treatment strategy based on the target blood uric acid concentration is necessary. Consequently, cases of gout will likely be observed more frequently by hip surgeons in clinical scenarios in the future. The objective of this review is to provide an overview of the pathophysiology of gout and subsequently examine recent advances in diagnostic methods and therapeutic agents based on an understanding of its underlying mechanisms. In addition, literature on gout-related issues affecting the hip joint, providing a useful reference for hip surgeons is examined.
10.Pathophysiology and Treatment of Gout Arthritis;including Gout Arthritis of Hip Joint: A Literature Review
Yonghan CHA ; Jongwon LEE ; Wonsik CHOY ; Jae Sun LEE ; Hyun Hee LEE ; Dong-Sik CHAE
Hip & Pelvis 2024;36(1):1-11
Gout is triggered by the accumulation of uric acid in the body, leading to hyperuricemia. Genetic, metabolic, and environmental factors can influence this condition. Excessive uric acid buildup results in the formation of monosodium urate (MSU) crystals, which precipitate in specific areas of the body, including the joints, where they can cause symptoms of gout. While the acute and chronic symptoms of gout have been well-documented, diagnosis of gout affecting the hip joint poses significant challenges. The global incidence of gout, the most prevalent form of inflammatory arthritis, is on the rise. Evaluation of the clinical signs, laboratory results, and imaging results is generally required for diagnosis of gout in cases where MSU crystals have not been detected. Hyperuricemia is considered a primary cause of arthritis symptoms, and comprehensive guidelines for treatment are available. Therefore, the choice of medication is straightforward, and moderate effectiveness of treatment has been demonstrated. Gout is a chronic disease, requiring lifelong uric acid-lowering medications, thus application of a treatment strategy based on the target blood uric acid concentration is necessary. Consequently, cases of gout will likely be observed more frequently by hip surgeons in clinical scenarios in the future. The objective of this review is to provide an overview of the pathophysiology of gout and subsequently examine recent advances in diagnostic methods and therapeutic agents based on an understanding of its underlying mechanisms. In addition, literature on gout-related issues affecting the hip joint, providing a useful reference for hip surgeons is examined.