• Nuclear Engineering and Technology
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• v.38 no.3
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• pp.239-250
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• 2006

Computational anthropomorphic phantoms are computer models of human anatomy used in the calculation of radiation dose distribution in the human body upon exposure to a radiation source. Depending on the manner to represent human anatomy, they are categorized into two classes: stylized and tomographic phantoms. Stylized phantoms, which have mainly been developed at the Oak Ridge National Laboratory (ORNL), describe human anatomy by using simple mathematical equations of analytical geometry. Several improved stylized phantoms such as male and female adults, pediatric series, and enhanced organ models have been developed following the first hermaphrodite adult stylized phantom, Medical Internal Radiation Dose (MIRD)-5 phantom. Although stylized phantoms have significantly contributed to dosimetry calculation, they provide only approximations of the true anatomical features of the human body and the resulting organ dose distribution. An alternative class of computational phantom, the tomographic phantom, is based upon three-dimensional imaging techniques such as magnetic resonance (MR) imaging and computed tomography (CT). The tomographic phantoms represent the human anatomy with a large number of voxels that are assigned tissue type and organ identity. To date, a total of around 30 tomographic phantoms including male and female adults, pediatric phantoms, and even a pregnant female, have been developed and utilized for realistic radiation dosimetry calculation. They are based on MRI/CT images or sectional color photos from patients, volunteers or cadavers. Several investigators have compared tomographic phantoms with stylized phantoms, and demonstrated the superiority of tomographic phantoms in terms of realistic anatomy and dosimetry calculation. This paper summarizes the history and current status of both stylized and tomographic phantoms, including Korean computational phantoms. Advantages, limitations, and future prospects are also discussed.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.2
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• pp.147-162
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• 2022

Purpose: To design a prospective study on endovascular closure of congenital portosystemic shunts. The primary endpoint was to assess the safety of endovascular closure. The secondary endpoint was to evaluate the clinical, analytical and imaging outcomes of treatment. Methods: Fifteen patients (age range: 2 days to 21 years; 10 male) were referred to our center due to congenital portosystemic shunts. The following data were collected prior to treatment: age, sex, medical history, clinical and analytical data, urine trimethylaminuria, abdominal-US, and body-CT. The following data were collected at the time of intervention: anatomical and hemodynamic characteristics of the shunts, device used, and closure success. The following data were collected at various post-intervention time points: during hospital stay (to confirm shunt closure and detect complications) and at one year after (for clinical, analytical, and imaging purposes). Results: The treatment was successful in 12 participants, migration of the device was observed in two, while acute splanchnic thrombosis was observed in one. Off-label devices were used in attempting to close the side-to-side shunts, and success was achieved using Amplatzer™ Ductus-Occluder and Amplatzer™ Muscular-Vascular-Septal-Defect-Occluder. The main changes were: increased prothrombin activity (p=0.043); decreased AST, ALT, GGT, and bilirubin (p=0.007, p=0.056, p=0.036, p=0.013); thrombocytopenia resolution (p=0.131); expansion of portal veins (p=0.005); normalization of Doppler portal flow (100%); regression of liver nodules (p=0.001); ammonia normalization (p=0.003); and disappearance of trimethylaminuria (p=0.285). Conclusion: Endovascular closure is effective. Our results support the indication of endovascular closure for side-to-side shunts and for cases of congenital absence of portal vein.

• Archives of Plastic Surgery
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• v.50 no.1
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• pp.30-36
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• 2023

Background Most children with facial lacerations require sedation for primary sutures. However, sedation guidelines for invasive treatment are lacking. This study evaluated the current status of the sedation methods used for pediatric facial laceration repair in Korea. Methods We surveyed one resident in each included plastic surgery training hospital using face-to-face interviews or e-mail correspondence. The health care center types (secondary or tertiary hospitals), sedation drug types, usage, and dosage, procedure sequence, monitoring methods, drug effects, adverse events, and operator and guardian satisfaction were investigated. Results We included 45/67 hospitals (67%) that used a single drug, ketamine in 31 hospitals and chloral hydrate in 14 hospitals. All health care center used similar sedatives. The most used drug administered was 5 mg/kg intramuscular ketamine (10 hospitals; 32%). The most common chloral hydrate administration approach was oral 50 mg/kg (seven hospitals; 50%). Twenty-two hospitals (71%) using ketamine followed this sequence: administration of sedatives, local anesthesia, primary repair, and imaging work-up. The most common sequence used for chloral hydrate (eight hospitals; 57%) was local anesthesia, administration of sedatives, imaging work-up, and primary repair. All hospitals that used ketamine and seven (50%) of those using chloral hydrate monitored oxygen saturation. Median operator satisfaction differed significantly between ketamine and chloral hydrate (4.0 [interquartile range, 4.0-4.0] vs. 3.0 [interquartile range, 3.0-4.0]; p <0.001). Conclusion The hospitals used various procedural sedation methods for children with facial lacerations. Guidelines that consider the patient's condition and drug characteristics are needed for safe and effective sedation.

• Korean Journal of Radiology
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• v.24 no.8
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• pp.784-794
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• 2023

Objective: To determine whether dynamic susceptibility contrast-enhanced (DSC) perfusion magnetic resonance imaging (MRI) can be used to evaluate posterior cerebral circulation in pediatric patients with moyamoya disease (MMD) who underwent anterior revascularization. Materials and Methods: This study retrospectively included 73 patients with MMD who underwent DSC perfusion MRI (age, 12.2 ± 6.1 years) between January 2016 and December 2020, owing to recent-onset clinical symptoms during the follow-up period after completion of anterior revascularization. DSC perfusion images were analyzed using a dedicated software package (NordicICE; Nordic NeuroLab) for the middle cerebral artery (MCA), posterior cerebral artery (PCA), and posterior border zone between the two regions (PCA-MCA). Patients were divided into two groups; the PCA stenosis group included 30 patients with newly confirmed PCA involvement, while the no PCA stenosis group included 43 patients without PCA involvement. The relationship between DSC perfusion parameters and PCA stenosis, as well as the performance of the parameters in discriminating between groups, were analyzed. Results: In the PCA stenosis group, the mean follow-up duration was 5.3 years after anterior revascularization, and visual disturbances were a common symptom. Normalized cerebral blood volume was increased, and both the normalized time-topeak (nTTP) and mean transit time values were significantly delayed in the PCA stenosis group compared with those in the no PCA stenosis group in the PCA and PCA-MCA border zones. TTP_PCA (odds ratio [OR] = 6.745; 95% confidence interval [CI] = 2.665-17.074; P < 0.001) and CBV_PCA-MCA (OR = 1.567; 95% CI = 1.021-2.406; P = 0.040) were independently associated with PCA stenosis. TTP_PCA showed the highest receiver operating characteristic curve area in discriminating for PCA stenosis (0.895; 95% CI = 0.803-0.986). Conclusion: nTTP can be used to effectively diagnose PCA stenosis. Therefore, DSC perfusion MRI may be a valuable tool for monitoring PCA stenosis in patients with MMD.

• Clinical and Experimental Pediatrics
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• v.62 no.7
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• pp.281-285
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• 2019

Purpose: To evaluate the association between elevated S100B levels with brain tissue damage seen in abnormalities of head magnetic resonance imaging (MRI; diffusion tensor imaging [DTI] sequence) in patients with status epilepticus (SE). Methods: An analytical observational study was conducted in children hospitalized at Dr Soetomo Hospital, Surabaya, from July to December 2016. The patients were divided into 2 groups: SE included all children with a history of SE; control included all children with febrile seizure. Blood samples of patients were drawn within 24 hours after admission. SE patients also underwent cranial MRI with additional DTI sequencing. The Mann-Whitney test and Spearman test were used for statistical analysis. Results: Fifty-three patients were enrolled the study. In the 24 children with SE who met the inclusion criteria, serum S100B and cranial MRI findings were assessed. Twenty-two children admitted with febrile seizures became the control group. Most patients were male (66.7%); the mean age was 35.8 months (standard deviation, 31.09). Mean S100B values of the SE group ($3.430{\pm}0.141{\mu}g/L$) and the control group ($2.998{\pm}0.572{\mu}g/L$) were significantly different (P<0.05). A significant difference was noted among each level of encephalopathy based on the cranial MRI results with serum S100B levels and the correlation was strongly positive with a coefficient value of 0.758 (P<0.001). Conclusion: In SE patients, there is an increase of serum S100B levels within 24 hours after seizure, which has a strong positive correlation with brain damage seen in head MRI and DTI.

• Journal of radiological science and technology
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• v.40 no.3
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• pp.355-361
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• 2017

Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied.

• Advances in pediatric surgery
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• v.11 no.2
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• pp.150-156
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• 2005

Failure of the urachus to regress completely results in anomalies that may be classified as patent urachus, urachal sinus, urachal cyst and bladder diverticula. The presenting symptoms of children with urachal anomalies are variable and uniform guidelines for diagnosis and treatment are lacking. The purpose of this study was to analyze our experience and develop conclusions regarding the presentation, diagnosis and treatment of urachal anomalies. We retrospectively analyzed the records of 32 patients who were admitted for urachal anomalies from March 1995 to February 2005. The age distribution of these patients at presentation ranged from 1 day to 14 years old (median age 1 month). There were 20 boys and 12 girls. The 32 cases comprised 13 cases of urachal sinus (40.6 %), 10 urachal cyst (31.3 %), and 9 patent urchus (28.1 %). In 30 patients ultrasonography was used for diagnosis and 2 patients with patent urachus were explored without using a diagnostic method. Twenty-three patients were confirmed by ultrasonography alone and 7 patients were examined using additional modalities, namely, computed tomography for 2 patients with an urachal cyst, magnetic resonance imaging for 1 patient with an urachal cyst, and fistulography for 3 patients with an urachal sinus. The presenting symptoms were umbilical discharge (14 patients), umbilical granuloma (8), abdominal pain and fever (3), fever (3), abdominal pain (2), and a low abdominal mass (2). Excision was performed in 29 patients, and 3 patients were conservatively managed. Urachal anomalies in children most frequently presented in neonates, and the most common complaint was umbilical discharge with infection. Urachal anomalies can be diagnosed by a physical examination and an appropriate radiographic test. Ultrasound was the most useful diagnostic method. Complete surgical excision of an urachal anomaly is recommended to avoid recurrence, and the rare development of carcinoma.

• Childhood Kidney Diseases
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• v.20 no.2
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• pp.92-96
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• 2016

Henoch-$Sch{\ddot{o}}nlein$ purpura (HSP) is the most common vasculitis in children, mainly affecting the small vessels of the skin, joints, gastrointestinal tract, and kidneys. Although most cases of HSP resolve spontaneously without sequelae, serious nephrological and intestinal problems may occur in some cases. We experienced a case of HSP complicated by simultaneous intussusception and nephritis in a 14-year-old boy who developed a sudden abdominal pain and gross hematuria on the 11th day after onset of the disease. Imaging studies revealed intussusception that required emergency laparotomy. Despite treatment with steroid and angiotensin-converting enzyme inhibitors, nephritis and nephrosis progressed for 4 weeks, and renal biopsy was performed to confirm the diagnosis. Cyclosporin A therapy was started, and remission of proteinuria was achieved after 5 months. However, the nephritis recurred and worsened to end-stage renal failure during 15 years of follow-up.

• Clinical and Experimental Pediatrics
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• v.48 no.6
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• pp.660-664
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• 2005

Infantile hemangioendothelioma(IHE) of the liver is the most common vascular tumor in infants before the age of 6 months. It is a histologically benign tumor with potentially life-threatening complications. The clinical manifestations are variable, ranging from asymptomatic forms to intractable high-output heart failure. In addition, abdominal mass, intraperitoneal hemorrhage due to rupture of mass, respiratory distress, hematologic abnormalities and jaundice can occur. Diagnostic work-up is through doppler ultrasound sonography, computed tomography scan, magnetic resonance imaging and angiography. Treatment consists of medical treatment, interventional therapy, surgical resection and liver transplantation. We experienced symptomatic IHE in a premature neonate who presented with high output heart failure and respiratory distress. Initial medical treatment and steroid therapy failed to improve his condition. Coil embolization of left hepatic artery resulted in improvement of respiratory symptoms. However, a left lobectomy was performed because the mass size was not decreased with development of collateral vessels. The infant was well, after a successful discharge from the hospital.

• Advances in pediatric surgery
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• v.13 no.1
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• pp.66-71
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• 2007

There have been no definitive preoperative diagnostic imaging studies for impalpable testes. We observed the effectiveness of laparoscopy for detecting impalpable testes not identified with ultrasonography (USG) or careful physical examination under general anesthesia. We retrospectively reviewed 117 patients (118 testes) who were operated upon for undescended testes from January 1998 to December 2004. The testes of these patients were palpable in 97(82 %) and impalpable in 21 (18 %). We analyzed the preoperative diagnostic method, site of the testes, operative method and operative findings of the 21 impalpable testes. Preoperative USG and physical examination under general anesthesia were performed on 20 patients, and 12 patients' testes could be localized. Eight patients whose testes could not be localized with USG and physical examination underwent laparoscopy. Seven of the 8 patients had testes in inguinal canal and 4 of these were atrophied and underwent orchiectomy because of atrophy (2) and vanishing (2). Only 1 patient had bilateral intraabdominal testes and one of the testes was atrophied. Laparoscopy was a useful method for detecting impalpable testes, but the clinical application might be limited because the location of atrophic or vanishing testes was mainly inferior to internal inguinal ring.