PURPOSE: This paper introduces a computationally inexpensive context-dependent classification of multi-echo MRI with Bayes compound decision model. In order to produce accurate region segmentation especially in homogeneous area and along boundaries of the regions, we propose a classification method that uses contextual information of local neighborhood system in the image. MATERIAL AND METHOD: The performance of the context free classifier over a statistically heterogeneous image can be improved if the local stationary regions in the image are disassociated from each other through the mechanism of the interaction parameters defined at the local neighborhood level. In order to improve the classification accuracy, we use the contextual information which resolves ambiguities in the class assignment of a pattern based on the labels of the neighboring patterns in classifying the image. Since the data immediately surrounding a given pixel is intimately associated with this given pixel, then if the true nature of the surrounding pixel is known this can be used to extract the true nature of the given pixel. The proposed context-dependent compound decision model uses the compound Bayes decision rule with the contextual information. As for the contextual information in the model, the directional transition probabilities estimated from the local neighborhood system are used for the interaction parameters. RESULTS: The context-dependent classification paradigm with compound Bayesian model for multi-echo MR images is developed. Compared to context free classification which does not consider contextual information, context-dependent classifier show improved classification results especially in homogeneous and along boundaries of regions since contextual information is used during the classification. CONCLUSION: We introduce a new paradigm to classify multi-echo MRI using clustering analysis and Bayesian compound decision model to improve the classification results.
Bays* ; Classification* ; Magnetic Resonance Imaging* ; Residence Characteristics

Twenty-six cases of fracture of the femur and tibia on the same leg in twenty-five patients were treated at the Dept. of Orthopedic Surgery, Kyungpook National University Hospital during the period of 1973 to 1979. Twenty-two patients were sustained by the motor vehicle accident. Open fractures of the femur and tibia were ten cases, and closed femur fracture and open tibia fracture were twelve cases. Concomitant Injuries were brain Injury in eight patients and hemorrhagic shock In seven patients. Eight patients were treated by internal fixation (Kuntschernall or Compression plate) on femur and by conservative treatment on tibia. Conservative treatment was done in eleven patients on both femur and tibia fracture. Five patients were amputated. Average healing time of fracture was: twenty-two weeks in femur and twenty-seven weeks in tibia. Functional end results were assessed and rated with satisfactory results In six patients and fair and poor in elght patients respectively.
Brain Injuries ; Clinical Study ; Femur ; Fractures, Open ; Gyeongsangbuk-do ; Humans ; Leg ; Motor Vehicles ; Orthopedics ; Shock, Hemorrhagic ; Tibia

Authors have treated a case of glomus tumor which was occurred in the tip of the right thumb, 34 years old female. The patient has complained of pain, tenderness, and cold sensitivity on the lateral side of the tip of the right thumb for 10 years. Reddish purple discolorarion was noticed under the nail bed. On X-ray, erosion of the lateral cortex of the distal phalanx and increased soft tissue density around the erosion was noted. Grossly, the tumor was purple in color, more deeply colored than the surrounding tissue and tumor tissue will shell out of the surrounding bone and soft tissue. Glomus tumor was confirmed by the excisional biopsy.
Biopsy ; Female ; Glomus Tumor ; Humans ; Thumb

This review discusses the production of alpha-particle-emitting radionuclides in radioimmunotherapy. Radioimmunotherapy labeled with alpha-particle is expected to be very useful for the treatment of monocellular cancer (e.g. leukemia) and micrometastasis at an early stage, residual tumor remained in tissues after chemotherapy and tumor resection, due to the high linear energy transfer (LET) and the short path length in biological tissue of alpha particle. Despite of the expected effectiveness of alpha-particle in radioimmunotherapy, its clinical research has not been activated by the several reasons, shortage of a suitable a-particle development and a reliable radionuclide production and supply system, appropriate antibody and chelator development. Among them, the establishment of radionuclide development and supply system is a key factor to make an alpha-immunotherapy more popular in clinical trial. Alpha-emitter can be produced by several methods, natural radionuclides, reactor irradiation, cyclotron irradiation, generator system and elution. Due to the sharply increasing demand of 213Bi, which is a most promising radionuclide in radioimmunotherapy and now has been produced with reactor, the cyclotron production system should be developed urgently to meet the demand.
Alpha Particles ; Cyclotrons ; Drug Therapy ; Linear Energy Transfer ; Neoplasm Micrometastasis ; Neoplasm, Residual ; Radioimmunotherapy* ; Radioisotopes*

PURPOSE: To evaluate abnormal neurosonographic (NSG) findings of thalami and basal ganglia in full term babies with hypoxic-ischemic encephalopathy and to correlate the findings with follow-up studies and prognosis. METHODS: We evaluated 13 full term babies with abnormal NSG findings of thalarni and basal ganglia. NSG was performed within 7 days after clinical abnormalities. Follow-up NSG was done in 11 cases; CT scan in 4 and MRI in 7. We classified NSG findings as diffuse, unilateral, and focal types according to increased echogenicity and evaluated prognosis based on follow-up studies and neurological sequelae. RESULTS: Nine cases of diffuse type had diffuse echogenic changes of bilateral thalami and basal ganglia, slit-like lateral ventricles suggesting cerebral edema, and increased parenchymal echogenicity. In diffuse type, follow-up studies showed more prominent echogencities and ventricular dilatations and cerebromalacia. One case of unilateral type caused by thromboembolism had unilateral echogenicity of right thalamus and basal ganglia with increased echogenicity of the ipsilateral cerebral hemisphere and compression of the lateral ventricle, suggesting cerebral infarction. Follow-up study showed unilateral cystic cerebromalacia. Three cases of focal type had a localized echogenic area in thalamus with lacunar infarction, which decreased in size during follow-up. Among nine cases of diffuse type, one died within 2 days, two were discharged against medical advice, and six had severe neurologic sequelae. One case of unilateral type had a moderate degree of neurologic sequelae. All 3 cases of focal type had normal development. CONCLUSION: Pattems of abnormal echogenicity in thalami and basal ganglia in fullterm infants with hypoxic-ischemic encephalopathy are correlated with the outcome and may be helpful for treatment planning.
Basal Ganglia* ; Brain ; Brain Edema ; Brain Ischemia* ; Cerebral Infarction ; Cerebrum ; Dilatation ; Encephalomalacia ; Follow-Up Studies ; Humans ; Hypoxia-Ischemia, Brain ; Infant* ; Lateral Ventricles ; Magnetic Resonance Imaging ; Prognosis* ; Stroke, Lacunar ; Thalamus* ; Thromboembolism ; Tomography, X-Ray Computed

No abstract available.
Breast Neoplasms* ; Breast*

No abstract available.
Endocardial Cushion Defects* ; Endocardial Cushions* ; Hernia, Diaphragmatic*

PURPOSE: This paper introduces an improved classification approach which adopts a deterministic relaxation method and an agglomerative clustering technique for the classification of MRI using neural network. The proposed approach can solve the problems of convergency to local optima and computational burden caused by a large number of input patterns when a neural network is used for image classification. MATERIALS AND METHODS: Application of Hopfield neural network has been solving various optimization problems. However, major problem of mapping an image classification problem into a neural network is that network is opt to converge to local optima and its convergency toward the global solution with a standard stochastic relaxation spends much time. Therefore, to avoid local solutions and to achieve fast convergency toward a global optimization, we adopt MFA to a Hopfield network during the classification. MFA replaces the stochastic nature of simulated annealing method with a set of deterministic update rules that act on the average value of the variable. By minimizing averages, it is possible to converge to an equilibrium state considerably faster than standard simulated annealing method. Moreover, the proposed agglomerative clustering algorithm which determines the underlying clusters of the image provides initial input values of Hopfield neural network. RESULTS: The proposed approach which uses agglomerative clustering and deterministic relaxation approach resolves the problem of local optimization and achieves fast convergency toward a global optimization when a neural network is used for MRI classification. CONCLUSION: In this paper, we introduce a new paradigm to classify MRI using clustering analysis and deterministic relaxation for neural network to improve the classification results.
Classification* ; Magnetic Resonance Imaging ; Relaxation*

OBJECTIVE: To evaluate the response of sodium nitroprusside(SNP) in the treatment of persistent pulmonary hypertension of the newborn(PPHN). METHODS: Among neonates with PPHN who were admitted at the NICU of the Department of Pediatrics of Dongsan Medical Center, Keimyung University between June 1996 and May 1999, 10 cases were treated with SNP. The diagnosis of PPHN was made by echocardiography, and SNP was administered by continuous infusion via peripheral or central vein, and the initial dose was 0.5microgram/kg/min. The rate of infusion was subsequently titrated, by repeatedly increasing the rate of infusion, until a desired or adverse effect was observed, the maximal rate of SNP infusion did not exceed 0.5microgram /kg/min. Serial vital signs, arterial blood gases, platelet counts, and oxygenation index(OI) were measured before and after SNP infusion periodically. Statistical analyses were assessed by ANOVA test using SAS package. Significance was assumed at P<0.05. RESULTS: All the patients were outborn. And fullterm, c-section delivery neonates were more common. Common associated diseases were pneumonia(including meconium aspiration syndrome, 50%), perinatal asphyxia(30%) and respiratory distress syndrome(30%). And 8 cases(80%) were improved(responsive group), 2 cases were not improved(nonresponsive group). Between both groups, there were not noted signigicant difference in mean 1-& 5-min Apgar score, arterial pH, PO2 and PCO2, maximal infusion rate and duration of SNP. Mean baseline OIs were 55.2 in responsive group and 57.9 in nonresponsive group. After SNP therapy, OI of the former was reduced significantly(p<0.005), but OI of the latter didn't change significantly. During SNP therapy, transient hypotension was developed in 3 cases, and pulmonary hemorrhage in three, and one case with necrotizing enterocolitis, thrombocytopenia, or periventricular leukomalacia was noted. CONCLUSION: It was concluded that SNP can be used as a non-aggressive and low-cost primary treatment for the patient with PPHN.
Apgar Score ; Diagnosis ; Echocardiography ; Enterocolitis, Necrotizing ; Gases ; Hemorrhage ; Humans ; Hydrogen-Ion Concentration ; Hypertension, Pulmonary* ; Hypotension ; Infant, Newborn* ; Leukomalacia, Periventricular ; Meconium Aspiration Syndrome ; Nitroprusside* ; Oxygen ; Pediatrics ; Platelet Count ; Sodium* ; Thrombocytopenia ; Veins ; Vital Signs

A retrospecive clinical observation was done on 325 cases of hypertension admitted to Department of internal Medicine of Seoul Red Cross Hospital from January, 1979 to December, 1982. The following results have been obtained. 1) The observed patients were 157 males and 168 females, and the prevalence rate of malignant hypertension among 325 hypertensions was 16 cases (4.9 percent). Among 16 cases of malignant hypertension 9 cases were male and 7 cases were female. Most frequently in 50, 60 and 40 years of age in this order each sex. 2) The average admitted dates are 7 days. 27 cases (8.3percent) were readmitted above 2 times after one discharged. 3) The most freqeuntly observed duration of Known hypertension 37.9 percent was 6-10 years and the next frequently observed duration 37.4 percent was 3-5 years. 4) The highest percentage of malignant hypertension had systolic blood pressure between 190-209mmHg and diastolic blood pressure between 150-169mmHg. 5) The highest percentage of seasonal number was spring (31.1 percent) and the next autumn, summer, winter in this order and the prevalence rates of hypertention are increased average 1.9% of each year. 6) The 78.5 percent of the patients were found that their blood pressure were abnormaly high when they were examined with related symptoms on admission, and they major symptorms were headache and dizziness. 7) The physical examination on admission, tachycardia (56percent), tachypnea (15.1percent), semicoma to coma (12.9 percent) in this order. 8) The status of treatment in hypertension on admission was as follows; imtermittent treatment 54.5 percent, no treatment 31 percent and continuous treatment 14.5 percent in this order. 9) In the chest X-ray on admission, the most frequent finding was cardiomegaly, and normal finding was the next frequency. The pulmonary Tbc was noted in 12.6 percent. 10) According to the degree of fundoscopic abnormality by K-W classification stage III was 68.8 percent and stage IV was 31.2 percent. 11) Electrocardiogram abnormalities were 44.9 percent, and 87.5 percent of malignant hypertension revealed electrocardiographic abnormalities and left ventricle hypertrophy was observed in 70.5 percent. 12) Hypercholesterolemia 78 percent, Hypernatremia 69.8 percent, Hypokalemia 22.8 percent, serum chloride 34.5 percent (<95m Eg/l), BUN 53.8 percent (>20mg/dl) and creatinine 45.8 percent (>3mg/dl) on admission. 13) Proteinuria was observed in 87.5 percent of malignant hypertension. 14) Marked improved for clinically was 24 percent and mortality rate was 5.2 percent, most common cause of death are cardiovascular accident (64.7percent) and renal failure (23.5percent).
Blood Pressure ; Cardiomegaly ; Cause of Death ; Classification ; Coma ; Creatinine ; Dizziness ; Electrocardiography ; Female ; Headache ; Heart Ventricles ; Humans ; Hypercholesterolemia ; Hypernatremia ; Hypertension ; Hypertension, Malignant ; Hypertrophy ; Hypokalemia ; Internal Medicine ; Male ; Mortality ; Physical Examination ; Prevalence ; Proteinuria ; Red Cross ; Renal Insufficiency ; Seasons ; Seoul ; Tachycardia ; Tachypnea ; Thorax