• Progress in Medical Physics
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• v.26 no.4
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• pp.286-293
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• 2015

The purpose of this study was to evaluate the set up accuracy using stereotactic body frame and frameless immobilizer for lung stereotactic body radiation therapy (SBRT). For total 40 lung cancer patients treated by SBRT, 20 patients using stereotactic body frame and other 20 patients using frameless immobilizer were separately enrolled in each group. The setup errors of each group depending on the immobilization methods were compared and analyzed. All patients received the dose of 48~60 Gy for 4 or 5 fractions. Before each treatment, a patient was first localized to the treatment isocenter using room lasers, and further aligned with a series of image guidance procedures; orthogonal kV radiographs, cone-beam CT, orthogonal fluoroscopy. The couch shifts during these procedures were recorded and analyzed for systematic and random errors of each group. Student t-test was performed to evaluate significant difference depending on the immobilization methods. The setup reproducibility was further analyzed using F-test with the random errors excluding the systematic setup errors. In addition, the ITV-PTV margin for each group was calculated. The setup errors for SBF were $0.05{\pm}0.25cm$ in vertical direction, $0.20{\pm}0.38cm$ in longitudinal direction, and $0.02{\pm}0.30cm$ in lateral direction, respectively. However the setup errors for frameless immobilizer showed a significant increase of $-0.24{\pm}0.25cm$ in vertical direction while similar results of $0.06{\pm}0.34cm$, $-0.02{\pm}0.25cm$ in longitudinal and lateral directions. ITV-PTV margins for SBF were 0.67 cm (vertical), 0.99 cm (longitudinal), and 0.83 cm (lateral), respectively. On the other hand, ITV-PTV margins for Frameless immobilizer were 0.75 cm (vertical), 0.96 cm (longitudinal), and 0.72 cm (lateral), indicating less than 1 mm difference for all directions. In conclusion, stereotactic body frame improves reproducibility of patient setup, resulted in 0.1~0.2 cm in both vertical and longitudinal directions. However the improvements are not substantial in clinic considering the effort and time consumption required for SBF setup.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.7 no.1
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• pp.16-23
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• 2004

Purpose: In this study, we tried to evaluate the clinical characteristics or circumstances that lead to unintentionally the delay in the diagnosis of intussusception or to the wrong direction that prevent the proper management early. Methods: All the patients of intussusception with delayed diagnosis in the department of pediatrics or emergency room at Gyeongsang National University Hospital from 1990 to 2003 were enrolled and reviewed retrospectively. Results: There were 8 boys and 6 girls and their median age was 8 months (range 2 months to 10 years). Their initial symptoms and signs were vomiting, seizure, diarrhea, lethargy, irritability, bloody stool, palpable abdominal mass, foul odor of urine and tachycardia. Clinical diagnosis or impressions at admission consisted of acute gastroenteritis, shigellosis and toxic encephalopathy, convulsive disorders, urinary tract infections, sepsis, abdominal mass and intestinal obstruction. Eight patients were luckily diagnosed due to the delayed manifestations of cyclic irritability or currant jelly stool. Six patients were not paid attentions for the possibilities of intussusception and diagnosed serendipitiously by the abdominal sonography or CT during the evaluation of the abdominal mass or distension. Only five of 14 cases (35.7%) were successfully managed by barium or air reductions. The other 9 cases needed surgical operations. Conclusion: Delayed diagnosis of intussusception arise when doctors initially diagnose the patients incorrectly due to the unusual presentations or when they overlook the newly arising symptoms or signs suggestive intussusception after the admission because they are ardently attached to the first impressions or initial clinical diagnosis.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.1
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• pp.127-132
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• 2010

Purpose: Because of limitation of image acquisition method and acquisition time, scatter correction cannot perform easily in SPECT study. But in our hospital, could provide to clinic doctor of scatter corrected images, through introduction of new generation gamma camera has function of simple scatter correction. Taking this opportunity, we will compare scatter corrected and non-scatter corrected image from image quality of point of view. Materials and Methods: We acquisite the 'Hoffman brain phantom' SPECT image and '1mm line phantom' SPECT image, each 18 times, with GE Infinia Hawkeye 4, SPECT-CT gamma camera. At first, we calculated each contrast from axial slice of scatter corrected and non-scatter corrected SPECT image of 'Hoffman brain phantom'. and next, calculated each FWHM of horizontal and vertical from axial slice of scatter corrected and non-scatter corrected SPECT image of '1mm line phantom'. After then, we attempted T test analysis with SAS program on data, contrast and resolution value of scatter corrected and non-scatter corrected image. Results: The contrast of scatter corrected image, elevated from 0.3979 to 0.3509. And the resolution of scatter corrected image, elevated from 3.4822 to 3.6375. p value were 0.0097 in contrast and <0.0001 in resolution. We knew the fact that do improve of contrast and resolution through scatter correction. Conclusion: We got the improved SPECT image through simple and easy way, scatter correct. We will expect to provide improved images, from contrast and resolution point of view. to our clinic doctor.

• Journal of Chest Surgery
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• v.43 no.2
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• pp.139-143
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• 2010

Background: Thoracic empyema remains a serious problem despite the availability of modern diagnostic methods and appropriate antibiotics. The condition presents in many different forms and stages that require different therapeutic options. Video-assisted thoracic surgery (VATS) has become increasingly popular for use in the treatment of empyema. Material and Method: From January 2005 to May 2009, VATS was performed in 36 patients with pleural empyema and for whom chest-tube drainage and antibiotic therapy had failed or the CT scan showed multiseptate disease. The perioperative clinical factors were analyzed for all the study patients. Result: All the patients underwent VATS, but it was necessary to convert to thoracotomy in one patient. The mean operation time was $90{\pm}38.5\;min$. For the operative evaluation, 11 patients were compatible with ATS stage III. The duration of chesttube insertion was $11.9{\pm}5.8$ (3~24) days. One patient did not improve and therefore this patient underwent additional open drainage. At discharge, costophrenic angle blunting was observed in 22 patients, pleural thickening was noted in 20 patients, both were noted in 17 patients and neither was noted in 11 patients. However, at follow-up, each of these changes was observed in 9, 7, 4 and 24 patients, respectively. All except one patient showed radiographic improvement. Conclusion: VATS is suitable for the treatment of early and fibrinopurulent thoracic empyema, and even in selected patients with stage III disease.

• The Journal of Korean Society for Radiation Therapy
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• v.22 no.2
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• pp.113-122
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• 2010

Purpose: To evaluate the accuracy of a target position at static and dynamic state by using Dynamic phantom for the difference between tumor's actual movement during respiratory gated radiation therapy and skin movement measured by RPM (Real-time Position Management). Materials and Methods: It self-produced Dynamic phantom that moves two-dimensionally to measure a tumor moved by breath. After putting marker block on dynamic phantom, it analyzed the amplitude and status change depending on respiratory time setup in advance by using RPM. It places marker block on dynamic phantom based on this result, inserts Gafchromic EBT film into the target, and investigates 5 Gy respectively at static and dynamic state. And it scanned investigated Gafchromic EBT film and analyzed dose distribution by using automatic calculation. Results: As a result of an analysis of Gafchromic EBT film's radiation amount at static and dynamic state, it could be known that dose distribution involving 90% is distributed within margin of error of 3 mm. Conclusion: As a result of an analysis of dose distribution's change depending on patient's respiratory cycle during respiratory gated radiation therapy, it is expected that the treatment would be possible within recommended margin of error at ICRP 60.

• Radiation Oncology Journal
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• v.27 no.3
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• pp.163-168
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• 2009

Purpose: This study was a retrospective evaluation of the efficacy of stereotactic radiosurgery (SRS) in patients with >4 metastases to the brain. Materials and Methods: Between January 2004 and December 2006, 68 patients with $\geq$4 multiple brain metastases were included and reviewed retrospectively. Twenty-nine patients received SRS and 39 patients received whole brain radiotherapy (WBRT). Patients with small cell lung cancers and melanomas were excluded. The primary lesions were non-small cell lung cancer (69.0%) and breast cancer (13.8%) in the SRS group and non-small cell lung cancer (64.1%), breast cancer (15.4%), colorectal cancer (12.8%), esophageal cancer (5.1%) in the WBRT group. SRS involved gamma-knife radiosurgery and delivered 10~20 Gy (median, 16 Gy) in a single fraction with a 50% marginal dose. WBRT was delivered daily in 3 Gy fractions, for a total of 30 Gy. After completion of treatment, a follow-up brain MRI or a contrast-enhanced brain CT was reviewed. The overall survival and intracranial progression-free survival were compared in each group. Results: The median follow-up period was 5 months (range, 2~19 months) in the SRS group and 6 months (range, 4~23 months) in the WBRT group. The mean number of metastatic lesions in the SRS and WBRT groups was 6 and 5, respectively. The intracranial progression-free survival and overall survival in the SRS group was 5.1 and 5.6 months, respectively, in comparison to 6.1 and 7.2 months, respectively, in the WBRT group. Conclusion: SRS was less effective than WBRT in the treatment of patients with >4 metastases to the brain.

• Sleep Medicine and Psychophysiology
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• v.3 no.1
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• pp.56-67
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• 1996

Objectives : This study was designed to find clinical factors that could be differentiated by the lateralization of lesion and also find clinical factors to predict the lateralization of lesion. Methods : The subjects were 65 cooperative inpatients and outpatients with non-traumatic subcortical cerebrovascular disease without neurologic and psychiatric history from January 1995 to September 1995 ; 48 patients in Kyung Hee University, Oriental Medicine Hospital, 35 patients in Anam Hospital, Korea University were examined as subjects, but authors excluded 20 patients whose data were incomplete or who had uncertain lesions on brain CT or MRI. The 65 patients were divided into three groups-group with left hemispheric lesion, group with right hemispheric lesion, group with both hemispheric lesion-according to the finding of brain imaging study. Their cognitive functions were evaluated by the Benton Neuropsychological Assessment(BNA), their subjective neurobehavioral symptoms by Symptom Check List-90-R(SCL-90-R), their objective neurobehavioral symptoms by Neurobehavioral Rating Scale, and their daily living functions by Geriatric Evaluation by Relative's Rating Instrument(GERRl) and Instrumental Activities of Daily Living Scale(IADLs). Results : The results were as follows : 1) The results of cognitive function test indicated that the group with right hemispheric lesion showed low functions in Tactile Form Perception(left), the group with left hemispheric lesion showed low functions in Finger localization(right), the group with right hemispheric lesion showed low functions in Finger Localization(left). 2) Though, there were little significant differences in subjective neurobehavioral symptoms, the group with right hemispheric lesion showed higher scores in all symptoms except hostility. 3) Though, there were little significant differences in objective neurobehavioral symptoms, the group with both hemispheric lesion showed higher scores in cognition, guilty/disinhibition, the group with left hemispheric lesion showed higher scores in lability of mood, the group with right hemispheric lesion showed highest scores in psychotism, neurotism, agitation-hostility and decreased motivation/emotional withdrawal. 4) There were little significant differences among three groups in Daily Living Functions, but the group with right hemispheric lesion showed the lowest functions in Instrumental Activities of Daily Living. 5) As a result of discriminant analysis on each factor's contribution to the prediction of lesion, Finger Localization(left), Phoneme Discrimination and Tactile Form Perception(right) showed that they had the potentiality to predict lesion. Conclusion : The results suggest that there are little significant differences among the groups of three non-traumatic subcortical cerebrovascular disease in cognitive functions, but the group with right hemispheric lesion showed more serious and various changes in subjective and objective neurobehavioral symptoms, and showed low functions in Instrumental Activities of Daily Living. This results suggest the possibility that the decline of the daily living function in the group with right hemispheric lesion were due to various symptoms, not due to cognitive dysfunction. The confirmation of the possibility should be worked out through the follow-up study of some groups containing cortical lesion. Apart from these findings, Finger Localization, Tactile Form Perception(right) and Phoneme Discrimination suggest that they can be used as clinically valuable cognitive parameters that predict the lateralization of lesion in non-traumatic cerebrovascular disease.

• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.489-499
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• 1999

Background: The patient with bronchiectasis may have obstructive ventilatory impairment combined with mild restrictive ventilatory impairment due to fibrosis of surrounding lung parenchyme and pleural adhesions caused by chronic recurrent pulmonary infections. Since hyperinflation or emphysematous change can be occured in bronchiectasis, pulmonary functions such as lung volumes and diffusing capacity may also vary with associated emphysema. Methods: For the evaluation of lung volumes and diffusing capacity in bronchiectasis with respect to the anatomic types and severity of bronchiectasis, a total of 40 cases comprising 24 cases of tubular, and 16 cystic type of bronchiectasis were analyzed retrospectively. Correlation between lung functions and extent of bronchiectasis or associated emphysema detected in HRCT were also evaluated. Results: Vital capacity(VC) tended to decrease in cystic type than in tubular type. As the severity of bronchiectasis became serious, the VC were significantly reduced, whereas the total lung capacity(TLC), residual volume(RV) and its ratio to the total lung capacity(RV/TLC) had no significant difference. Lung clearance index(LCI) was significantly increased in cystic type than in tubular type, whereas the slope of phase III in single breath nitrogen curve($\triangle$N2/L) was not significantly changed regard to the type and severity of bronchiectasis. DLCO and DLCO/VA reflecting diffusing capacity were significantly decreased in cystic type and also as the severity of bronchiectasis became serious. The correlation coefficient of VC, DLCO and LCI with the extent of bronchiectasis were -0.322, -0.339 and 0.487, respectively, whereas other parameters were not significantly correlated with the extent of bronchiectasis. VC and DLCO correlated negatively with the extent of emphysema while RV, RV/TLC, LCI and $\triangle$N2/L correlated positively. Conclusion: These findings suggest that the reduction of VC and diffusing capacity or uneven distribution of inspired gas in bronchiectasis are related to both the extent of bronchiectasis and associated emphysema while increased residual volume be related to the extent of associated emphysema alone.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.263-270
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• 2008

Purpose: This study aimed to quantitatively measure the movement of tumors in real-time and evaluate the treatment accuracy, during the treatment of a liver tumor patient, who underwent radiosurgery with a Synchrony Respiratory motion tracking system of a robot CyberKnife. Materials and Methods: The study subjects included 24 liver tumor patients who underwent CyberKnife treatment, which included 64 times of treatment with the Synchrony Respiratory motion tracking system ($Synchrony^{TM}$). The treatment involved inserting 4 to 6 acupuncture needles into the vicinity of the liver tumor in all the patients using ultrasonography as a guide. A treatment plan was set up using the CT images for treatment planning uses. The position of the acupuncture needle was identified for every treatment time by Digitally Reconstructed Radiography (DRR) prepared at the time of treatment planning and X-ray images photographed in real-time. Subsequent results were stored through a Motion Tracking System (MTS) using the Mtsmain.log treatment file. In this way, movement of the tumor was measured. Besides, the accuracy of radiosurgery using CyberKnife was evaluated by the correlation errors between the real-time positions of the acupuncture needles and the predicted coordinates. Results: The maximum and the average translational movement of the liver tumor were measured 23.5 mm and $13.9{\pm}5.5\;mm$, respectively from the superior to the inferior direction, 3.9 mm and $1.9{\pm}0.9mm$, respectively from left to right, and 8.3 mm and $4.9{\pm}1.9\;mm$, respectively from the anterior to the posterior direction. The maximum and the average rotational movement of the liver tumor were measured to be $3.3^{\circ}$ and $2.6{\pm}1.3^{\circ}$, respectively for X (Left-Right) axis rotation, $4.8^{\circ}$ and $2.3{\pm}1.0^{\circ}$, respectively for Y (Crania-Caudal) axis rotation, $3.9^{\circ}$ and $2.8{\pm}1.1^{\circ}$, respectively for Z (Anterior-Posterior) axis rotation. In addition, the average correlation error, which represents the treatment's accuracy was $1.1{\pm}0.7\;mm$. Conclusion: In this study real-time movement of a liver tumor during the radiosurgery could be verified quantitatively and the accuracy of the radiosurgery with the Synchrony Respiratory motion tracking system of robot could be evaluated. On this basis, the decision of treatment volume in radiosurgery or conventional radiotherapy and useful information on the movement of liver tumor are supposed to be provided.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.4
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• pp.271-278
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• 2012

Purpose: Recently implant surgical guides were used for accurate and atraumatic operation. In this study, the accuracy of two different types of surgical guides, positioning device fabricated and stereolithography fabricated surgical guides, were evaluated in four different types of tooth loss models. Materials and methods: Surgical guides were fabricated with stereolithography and positioning device respectively. Implants were placed on 40 models using the two different types of surgical guides. The fitness of the surgical guides was evaluated by measuring the gap between the surgical guide and the model. The accuracy of surgical guide was evaluated on a pre- and post-surgical CT image fusion. Results: The gap between the surgical guide and the model was $1.4{\pm}0.3mm$ and $0.4{\pm}0.3mm$ for the stereolithography and positioning device surgical guide, respectively. The stereolithography showed mesiodistal angular deviation of $3.9{\pm}1.6^{\circ}$, buccolingual angular deviation of $2.7{\pm}1.5^{\circ}$ and vertical deviation of $1.9{\pm}0.9mm$, whereas the positioning device showed mesiodistal angular deviation of $0.7{\pm}0.3^{\circ}$, buccolingual angular deviation of $0.3{\pm}0.2^{\circ}$ and vertical deviation of $0.4{\pm}0.2mm$. The differences were statistically significant between the two groups (P<.05). Conclusion: The laboratory fabricated surgical guides using a positioning device allow implant placement more accurately than the stereolithography surgical guides in dental clinic.