1.Late Hemorrhagic Disease of Infancy.
Kwang Wook AHN ; Chull Zoo JUNG ; Hyo Seop JU ; Seung Woo MOON
Journal of the Korean Pediatric Society 1986;29(6):97-101
No abstract available.
2.Diagnostric Significance of Subxiphoid Two-Dimensional Echocardiography in Congenital Heart Desease of Chlidred.
Kwang Do LEE ; Cheol Woo KO ; Hong Bae KIM ; Sang Bum LEE ; Doo Hong AHN
Journal of the Korean Pediatric Society 1986;29(3):64-72
No abstract available.
Echocardiography*
;
Heart*
3.Sphincter Repair for Fecal Incontinence after Obstetric Injury.
Kwang Woo AHN ; Sang Jeon LEE ; Jin Woo PARK
Journal of the Korean Society of Coloproctology 1999;15(1):9-19
PURPOSE: We designed this study to evaluate efficacy of sphincter repair and factors influencing in patients with postobstetric fecal incontinence. METHODS: Twenty-one patients (mean age 42 years; range 23~67) undergoing sphincter repair for postobstetric fecal incontinence (mean duration 12 years; range 6 months~46 years) were evaluated prospectively. Preoperatively, standardized interviews, anorectal manometry and measurement of pudendal nerve terminal motor latency (PNTML) were performed. Incontinence was graded according to the Parks' classification: Grade 1 - continence to stool and flatus; Grade 2 - incontinent to flatus, some urgency to stool present but no incontinence; Grade 3 - incontinent to liquid stool; Grade 4 - incontinent to formed stool. Sphincter repair methods were overlap repair of external anal sphincter (EAS) in 4 patients, overlap repair of EAS with anterior levatorplasty in 15 patients, and overlap repair of EAS with anterior levatorplasty and postanal repair in 2 patients. Anorectal manometry at 3 months, and interviews at 3 months and 6 months after sphincter repair were performed again. Patients' satisfaction was classified as excellent, good, fair, and no improvement. RESULTS: Difficulty in first delivery was noticed in 18 patients and history of previous sphincter repair was noticed in 5 patients. Preoperatively, most patients showed high grade incontinence (grade 3 in 13 and grade 4 in 8 patients). After sphincter repair, 18 patients (85.7%) became grade 1 or 2, and 16 patients (76.2%) replied their functional satisfaction excellent or good. There were no difference between the results at 3 months and 6 months. Poor functional outcome was in 2 of 3 patients with bilaterally prolonged preoperative PNTML. Short duration of incontinence and young age at the time of repair favored good results. Previous sphincter repair did not influence the outcome. Postoperatively both anal pressure and high pressure zone length were significantly increased in patients with improved continence Postoperative complications were wound infection in 2 patients and necrosis at the apex of the advancement skin flap in 1 case but these did not influence the outcome. CONCLUSIONS: Most postobstetric fecal incontinence can be successfully treated with sphincter repair. Excellent results are expected when the duration of incontinence is short and the patients are young. Pudendal neuropathy seemed to be related to poor outcome.
Anal Canal
;
Classification
;
Fecal Incontinence*
;
Flatulence
;
Humans
;
Manometry
;
Necrosis
;
Postoperative Complications
;
Prospective Studies
;
Pudendal Nerve
;
Pudendal Neuralgia
;
Skin
;
Wound Infection
4.A Novel Approach for Estimating the Effective Atomic Number Using Dual Energy
Jeong Heon KIM ; So Hyun AHN ; Kwang Woo PARK ; Jin Sung KIM
Progress in Medical Physics 2025;36(1):1-7
Purpose:
This study aimed to present a novel method for estimating the effective atomic number(Zeff ) using dual-energy computed tomography (DECT) designed to improve accuracy andstreamline clinical workflows by reducing computational complexity.
Methods:
The proposed model leverages the DECT-derived mass attenuation coefficients without detailed compositional analysis. By incorporating additional parameters into the conventional Rutherford model, such as exponential and trigonometric functions, the model effectively capturescomplex variations in attenuation, enabling precise Zeff estimation. Model fitting was performedusing dual-energy data and evaluated using the percentage difference in error rates.
Results:
Compared with the Rutherford model, which recorded a maximum error rate of 0.55%, the proposed model demonstrated a significantly lower maximum error rate of 0.15%, highlightingits precision. Zeff estimates for various materials closely matched the reference values, confirmingthe improved accuracy of the model.
Conclusions
The proposed DECT-based model provides a practical and efficient approach to Zeff estimation, with potential applications in radiation oncology, particularly for accurate stopping power ratio calculations in proton and heavy ion therapies.
5.A Novel Approach for Estimating the Effective Atomic Number Using Dual Energy
Jeong Heon KIM ; So Hyun AHN ; Kwang Woo PARK ; Jin Sung KIM
Progress in Medical Physics 2025;36(1):1-7
Purpose:
This study aimed to present a novel method for estimating the effective atomic number(Zeff ) using dual-energy computed tomography (DECT) designed to improve accuracy andstreamline clinical workflows by reducing computational complexity.
Methods:
The proposed model leverages the DECT-derived mass attenuation coefficients without detailed compositional analysis. By incorporating additional parameters into the conventional Rutherford model, such as exponential and trigonometric functions, the model effectively capturescomplex variations in attenuation, enabling precise Zeff estimation. Model fitting was performedusing dual-energy data and evaluated using the percentage difference in error rates.
Results:
Compared with the Rutherford model, which recorded a maximum error rate of 0.55%, the proposed model demonstrated a significantly lower maximum error rate of 0.15%, highlightingits precision. Zeff estimates for various materials closely matched the reference values, confirmingthe improved accuracy of the model.
Conclusions
The proposed DECT-based model provides a practical and efficient approach to Zeff estimation, with potential applications in radiation oncology, particularly for accurate stopping power ratio calculations in proton and heavy ion therapies.
6.A Novel Approach for Estimating the Effective Atomic Number Using Dual Energy
Jeong Heon KIM ; So Hyun AHN ; Kwang Woo PARK ; Jin Sung KIM
Progress in Medical Physics 2025;36(1):1-7
Purpose:
This study aimed to present a novel method for estimating the effective atomic number(Zeff ) using dual-energy computed tomography (DECT) designed to improve accuracy andstreamline clinical workflows by reducing computational complexity.
Methods:
The proposed model leverages the DECT-derived mass attenuation coefficients without detailed compositional analysis. By incorporating additional parameters into the conventional Rutherford model, such as exponential and trigonometric functions, the model effectively capturescomplex variations in attenuation, enabling precise Zeff estimation. Model fitting was performedusing dual-energy data and evaluated using the percentage difference in error rates.
Results:
Compared with the Rutherford model, which recorded a maximum error rate of 0.55%, the proposed model demonstrated a significantly lower maximum error rate of 0.15%, highlightingits precision. Zeff estimates for various materials closely matched the reference values, confirmingthe improved accuracy of the model.
Conclusions
The proposed DECT-based model provides a practical and efficient approach to Zeff estimation, with potential applications in radiation oncology, particularly for accurate stopping power ratio calculations in proton and heavy ion therapies.
7.A Novel Approach for Estimating the Effective Atomic Number Using Dual Energy
Jeong Heon KIM ; So Hyun AHN ; Kwang Woo PARK ; Jin Sung KIM
Progress in Medical Physics 2025;36(1):1-7
Purpose:
This study aimed to present a novel method for estimating the effective atomic number(Zeff ) using dual-energy computed tomography (DECT) designed to improve accuracy andstreamline clinical workflows by reducing computational complexity.
Methods:
The proposed model leverages the DECT-derived mass attenuation coefficients without detailed compositional analysis. By incorporating additional parameters into the conventional Rutherford model, such as exponential and trigonometric functions, the model effectively capturescomplex variations in attenuation, enabling precise Zeff estimation. Model fitting was performedusing dual-energy data and evaluated using the percentage difference in error rates.
Results:
Compared with the Rutherford model, which recorded a maximum error rate of 0.55%, the proposed model demonstrated a significantly lower maximum error rate of 0.15%, highlightingits precision. Zeff estimates for various materials closely matched the reference values, confirmingthe improved accuracy of the model.
Conclusions
The proposed DECT-based model provides a practical and efficient approach to Zeff estimation, with potential applications in radiation oncology, particularly for accurate stopping power ratio calculations in proton and heavy ion therapies.
8.A Novel Approach for Estimating the Effective Atomic Number Using Dual Energy
Jeong Heon KIM ; So Hyun AHN ; Kwang Woo PARK ; Jin Sung KIM
Progress in Medical Physics 2025;36(1):1-7
Purpose:
This study aimed to present a novel method for estimating the effective atomic number(Zeff ) using dual-energy computed tomography (DECT) designed to improve accuracy andstreamline clinical workflows by reducing computational complexity.
Methods:
The proposed model leverages the DECT-derived mass attenuation coefficients without detailed compositional analysis. By incorporating additional parameters into the conventional Rutherford model, such as exponential and trigonometric functions, the model effectively capturescomplex variations in attenuation, enabling precise Zeff estimation. Model fitting was performedusing dual-energy data and evaluated using the percentage difference in error rates.
Results:
Compared with the Rutherford model, which recorded a maximum error rate of 0.55%, the proposed model demonstrated a significantly lower maximum error rate of 0.15%, highlightingits precision. Zeff estimates for various materials closely matched the reference values, confirmingthe improved accuracy of the model.
Conclusions
The proposed DECT-based model provides a practical and efficient approach to Zeff estimation, with potential applications in radiation oncology, particularly for accurate stopping power ratio calculations in proton and heavy ion therapies.
9.Therapeutic Effect of Itraconazole in Seborrheic Dermatitis.
Eun Joo PARK ; Chul Woo KIM ; Kwang Ho KIM ; Kyu Joong AHN ; Kwang Joong KIM
Korean Journal of Medical Mycology 2004;9(4):222-229
BACKGROUND: Seborrheic dermatitis is a very common chronic inflammatory disease. The causal factor of the disease is still unknown, but early investigators focused on the role of Malassezia yeasts. These yeasts are also normal skin commensals, thus their importance as pathogens in this disorder came to be doubted. However, it was subsequently found that treatment of seborrheic dermatitis with an antifungal agent not only resulted in clinical improvement but also reduced the number of Malassezia yeasts on the skin. OBJECT: The purpose of this study is to confirm relationship between seborrheric dermatits and Malassezia yeast, and to evaluate the therapeutic efficacy of oral itraconazole in the seborrheic dermatitis. METHODS: Using the scrub-wash technique in the glabella and swabbing technique in the scalp, the number of cultured Malassezia yeasts were counted in 30 patients with seborrheic dermatitis and 20 control persons. The patients took itraconazole, 100mg/day, during 4weeks. The clinical and mycologic score were measured at the initial evaluation, followed after 2weeks and 4weeks RESULT: The number of Malassezia yeasts in patient with seborrheic dermatits were significantly higher than in normal control group. There was statistically significant decrease in the clinical and mycological score after a 4 week trial of oral itraconazole in the seborrheic dermatitis group. CONCLUSION: This study indicates that Malassezia yeast may be one of the important causative factor of seborrheic dermatitis and itraconazole plays an important role in the treatment of seborrheic dermatitis
Dermatitis, Seborrheic*
;
Humans
;
Itraconazole*
;
Malassezia
;
Research Personnel
;
Scalp
;
Skin
;
Yeasts
10.Antioxidative Effect of Melatonin in Streptozotocin-Induced Diabetic Rats.
Hyung Joon YOO ; Do Ho MOON ; Hong Bae CHUNG ; Myung Soo AHN ; Kwang Sik YOON ; Byoung Jin AHN ; Jin SHIN ; An Chul CHUNG ; Young Joong CHO ; Hong Woo NAHM
Journal of Korean Society of Endocrinology 1998;13(1):45-51
BACKGROUND: An increase in oxidative stress has been suggested to play major roles in the complications of diabetes. The bulk of the experimental data favors enhanced free radicals in diabetes and antioxidant defense mechanisms may be reduced in diabetes. Melatonin, the major secretory product of the pineal gland has been shown to be a potent and specific hydroxyl radical scavenger. The purpose of our study was to determine the antioxidative effeet of melatonin in streptozotocin-induced diabetic rats. METHODS: Sprague-Dawley rats weighing 200-240 g were divided into 3 groups: normal controls(n-7), diabetic contmls(n-9), melatonin-treated diabetic animals(n-9). Diabetes was induced by intraperitoneal injection of streptozotoein(55 mg/kg body weight) and melatonin(6 mg/kg body weight) was orally administered for 20 days. At day 20 after streptozotocin administration, blood was collected for the assay of glucose, albumin and cholesterol. Erythrocyte membrane lipid peroxidation was determined by malonyldialdehyde(MDA) reactivity. RESULTS: 1) The MDA resctivity of erytbrocyte membrane in melatonin-treated diabetic animals (meanstandard deviation: 5.52+-1.52nmol/ml packed cells) were lower(p<0.05) than that in diabetic controls(7.68+-1.16nmol/mL packed cells). But, there was no significant difference between melatonin-treated diabetic animals and normal contls(4.93+-1.19 nmol/mL packed cells). 2) There were no significant differences of blood glucose and body weight between diabetic controls and melatonin-treated diabetic animals. CONCLUSION: These results show the antioxidative effect of melatonin in streptozotocin-induced diabetic rats. Further clinical and long-term experimental studies are needed to assess the effect of melatonin on development and progression of diabetic complications.
Animals
;
Blood Glucose
;
Body Weight
;
Cholesterol
;
Defense Mechanisms
;
Diabetes Complications
;
Erythrocyte Membrane
;
Free Radicals
;
Glucose
;
Hydroxyl Radical
;
Injections, Intraperitoneal
;
Lipid Peroxidation
;
Melatonin*
;
Membranes
;
Oxidative Stress
;
Pineal Gland
;
Rats*
;
Rats, Sprague-Dawley
;
Streptozocin