• Journal of Korean Neurosurgical Society
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• v.39 no.6
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• pp.423-426
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• 2006

Objective : There is still debate about the diagnostic efficacy of digital infrared thermographic imaging[DITI], nevertheless, it has been used for the diagnosis of carpal tunnel syndrome[CTS]. We performed comparative study between patient and control groups to investigate the diagnostic value of DITI in CTS. Methods : We studied 27 patients with electrodiagnostically-proven CTS and 18 symptom-free volunteers as a control. We measured thermal difference on DITI in the corresponding regions of the hands and forearms. We statistically analyzed the thermal data using a t-test. Results : The average thermal difference in the diagnosed patient group ranged from $0.0303^{\circ}C$ to $0.2856^{\circ}C$, while that in control group ranged from $0.0611^{\circ}C$ to $0.2878^{\circ}C$. In the CTS patient group, thermal difference between each 2nd finger was higher than that of other regions. However, there was no statistical significance between patient and control groups. Conclusion : We found that the diagnostic value of DITI in CTS was not sufficient. There should be a reconsideration of the usefulness of DITI in CTS.

• Journal of Sensor Science and Technology
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• v.27 no.6
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• pp.407-413
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• 2018

Most sleep apnea patients exhibit severe snoring, and long-lasting sleep apnea may cause insomnia, hypertension, cardiovascular diseases, stroke, and other diseases. Although polysomnography is the typical sleep diagnostic method to accurately diagnose sleep apnea by measuring a variety of bio-signals that occur during sleep, it is inconvenient as the patient has to sleep with attached electrodes at the hospital for the diagnosis. In this study, a diagnostic pillow is designed to measure respiration, heart rate, and snoring during sleep, using only one polyvinylidene fluoride (PVDF) sensor. A PVDF sensor with piezoelectric properties was inserted into a specially made instrument to extract accurate signals regardless of the posture during sleep. Wavelet analysis was used to identify the extractability and frequency domain signals of respiration, heart rate, and snoring from the signals generated by the PVDF sensor. In particular, to separate the respiratory signal in the 0.2~0.5 Hz frequency region, wavelet analysis was performed after removing 1~2 Hz frequency components. In addition, signals for respiration, heart rate, and snoring were separated from the PVDF sensor signal through a Butterworth filter and median filter based on the information obtained from the wavelet analysis. Moreover, the possibility of measuring sleep apnea from these separated signals was confirmed. To verify the usefulness of this study, data obtained during sleeping was used.

• Journal of Periodontal and Implant Science
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• v.22 no.1
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• pp.204.1-204.1
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• 1992

• Journal of the Korean Society of Visualization
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• v.2 no.1
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• pp.52-56
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• 2004

Several visualization techniques of laser diagnostics are presented for combustion phenomena, including Mie scattering for flow, Rayleigh and Raman scattering spectroscopy for major species, laser-induced fluorescence for minor species, and laser-induced incandescence for soot. These techniques have been applied to understand the various combustion phenomena more clearly, including buoyancy-dominant flow system, diffusion flam oscillation, laminar and turbulent lifted flames, flame propagation along a vortex ring, and soot zone characteristics. The usefulness of laser diagnostics on a better understanding of physical mechanism is demonstrated.

• Parasites, Hosts and Diseases
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• v.59 no.1
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• pp.77-82
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• 2021

As malaria remains a major health problem worldwide, various diagnostic tests have been developed, including microscopy-based and rapid diagnostic tests. LabChip real-time PCR (LRP) is a small and portable device used to diagnose malaria using lab-on-a-chip technology. This study aimed to evaluate the diagnostic performance of LRP for detecting malaria parasites. Two hundred thirteen patients and 150 healthy individuals were enrolled from May 2009 to October 2015. A diagnostic detectability of LRP for malaria parasites was compared to that of conventional RT-PCR. Sensitivity of LRP for Plasmodium vivax, P. falciparum, P. malariae, and P. ovale was 95.5%, 96.0%, 100%, and 100%, respectively. Specificity of LRP for P. vivax, P. falciparum, P. malariae, and P. ovale was 100%, 99.3%, 100%, and 100%, respectively. Cohen's Kappa coefficients between LRP and CFX96 for detecting P. vivax, P. falciparum, P. malariae, and P. ovale were 0.96, 0.98, 1.00, and 1.00, respectively. Significant difference was not observed between the results of LRP and conventional RT-PCR and microscopic examination. A time required to amplify DNAs using LRP and conventional RT-PCR was 27 min and 86 min, respectively. LRP amplified DNAs 2 times more fast than conventional RT-PCR due to the faster heat transfer. Therefore, LRP could be employed as a useful tool for detecting malaria parasites in clinical laboratories.

• Investigative Magnetic Resonance Imaging
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• v.9 no.2
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• pp.94-100
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• 2005

Purpose : This study was designed to evaluate the usefulness of 3T-TOF MR angiography (3T-TOF MRA) compared with transcranial Doppler sonography (TCD) and conventional angiography (CA) in patients with suspected cerebral infarction. Materials and Methods : Fifty four patients with clinical symptoms of cerebral infarction were involved in this study, and had undergone 3T-TOF MRA and TCD, with CA in 11 patients. On the basis of divisions of the carotid artery, four groups were designated: group I, both vertebral arteries and basilar artery; group II, segment between 2 cm below bifurcation of common carotid artery and genu portion of internal carotid artery; group III, segment between petrous portion of internal carotid artery and bifurcation of anterior and middle cerebral artery; group IV, from bifurcation of anterior and middle cerebral artery to thier distal branches. Two radiologists retrospectively reviewed the vascular imaging and stenosis in 3T-TOF MRA, TCD, and CA. Results : A total of 432 arteries, 108 in each group, were available. The assessment of vascular imaging quality in 3T-TOF MRA is scored 2.98, 2.96, 2.91, 2.88 in 4 groups, respectively. Agreement among 3T-TOF MR angiography, TCD, and CA was high. Conclusion : 3T-TOF MR angiography may be useful method for the assessment of stenotic lesions of cranial vasculature in patients with cerebral infarction.

• Korean Journal of Head & Neck Oncology
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• v.27 no.2
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• pp.204-209
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• 2011

Background and Objectives : The usefulness of fine needle aspiration biopsy(FNAB) for diagnosis of parotid gland tumors is controversial, because of the generalized belief requiring surgery for most parotid tumors. The aim of this study was to evaluate the efficacy of FNAB for diagnosis in parotid gland tumors. Material and Methods : FNAB was performed in 91 patients who underwent parotid surgery at Kangbuk Samsung Hospital from January 2007 to December 2010. The result of FNAB, 11 malignancies and 75 benign tumors and 5 non-neoplasms were analyzed and compared with the final histopathologic diagnoses. Sensitivity, specificity, accuracy, positive predictive value(PPV), and negative predictive value(NPV) were calculated using final histopathologic diagnosis of the surgical specimen as the standard diagnostic reference for comparative analysis. Results : 86 specimens(94.5%) were suitable for evaluation. We compared the result of FNAB and the final histopathology in 79(89.4%) cases. The sensitivity, specificity, accuracy, PPV, and NPV of FNAB for detecting pleomorphic adenoma was 95.8%, 88.4%, 92.3%, 90.2%, and 95.0%. In Warthin's tumor, results were 86.4%, 94.2%, 92.3%, 82.6%, and 95.6%. Among 11 patients who were diagnosed with malignancy on final histopathologic report, only 3(30%) patients were diagnosed with the same as on FNAB, the other 8 patients were initially diagnosed incorrectly as benign tumors in FNAB. There were no complications related to FNAB. Conclusion : Diagnostic accuracy for FNAB in benign parotid tumors was high. However, in malignant tumors, FNAB shows low diagnostic usefulness compared with benign tumors. FNAB can be effective and safe diagnostic technique for evaluating the benign parotid glands tumors.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.2
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• pp.433-437
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• 2009

The purpose of this study was to measure circumference of four body parts of each Sasang groups with Bioelectrical Impedance Analysis (BIA), and evaluate its usefulness for Sasang type diagnostic test. We obtained the circumference measures of neck (CN), chest (CC), waist (CW), and hip (CH) of 91 college students using BIA and standardized by sex and age. The validity of Sasang group prediction with CC was evaluated. The Tae-Eum group (104.87${\pm}$5.19, 108.47${\pm}$4.96, 116.00${\pm}$9.39, 110.4${\pm}$5.29. neck, chest, waist and hip, respectively) has significantly (p<0.001) bigger circumferences than So-Yang (97.79${\pm}$3.82, 100.02${\pm}$4.21, 101.02${\pm}$7.88, 101.95${\pm}$4.06) and So-Eum (95.63${\pm}$4.67, 96.93${\pm}$4.80, 97.63${\pm}$7.72, 99.86${\pm}$4.40) groups at very four measures. Discriminant functions with CC can be used for Tae-Eum Sasang type diagnostic test with 91.2% of overall Percentage Correctly Predicted (PCP). Tae-Eum type-specific sensitivity was 73.3% and Tae-Eum type-specific specificity was 94.7%. The strength and weakness of measurement and standardization methods for Sasang type diagnostic test, and the methods for the standardization of physical traits with sex and age were discussed. Our study showed distinctive physical features of Tae-Eum type and the usefulness of BIA for the Sasang type diagnosis.

• Journal of Trauma and Injury
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• v.22 no.2
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• pp.142-147
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• 2009

Purpose: Early diagnosis and management of therapeutic interventions are very important in chest trauma. Conventional chest X-rays (CXR) and computed tomography (CT) are the diagnostic tools that can be quickly implemented for chest trauma patients in the emergency department. In this study, the usefulness of the CT as a diagnostic measurement was examined by analyzing the ability to detect thoracic injuries in trauma patients who had visited the emergency department and undergone CXR and CT. Methods: This study involved 84 patients who had visited the emergency department due to chest trauma and who had undergone both CXR and CT during their diagnostic process. The patients' characteristics and early vital signs were examined through a retrospective analysis of their medical records, and the CXR and the CT saved in the Picture Archiving Communication System (PACS) were examined by a radiologist and an emergency physician to verify whether or not a lesion was present. Results: Pneumothoraxes, hemothoraxes, pneumomediastina, pulmonary lacerations, rib fractures, vertebral fractures, chest wall contusions, and subcutaneous emphysema were prevalently found in a statistically meaningful way (p<0.05) on the CT. Even though their statistical significance couldn' be verified, other disorders, including aortic injury, were more prevalently found by CT than by CXR. Conclusion: CT implemented for chest trauma patients visiting the emergency department allowed disorders that couldn' be found on CXR to be verified, which helped us to could accurately evaluate patients.

• Annals of Clinical Neurophysiology
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• v.14 no.1
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• pp.25-28
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• 2012

Background: Bell's palsy is the most common disease of cranial nerve. While most electrodiagnostic tests can detect the abnormality of facial nerve several days later in Bell's palsy, blink reflex usually reveals the abnormality earlier than other tests. Therefore, we investigated the diagnostic usefulness of blink reflex in the early stage of Bell's palsy. Methods: We performed a prospective investigation in patients with facial palsy. We enrolled patients with Bell's palsy who were evaluated within 7 days of symptom onset and excluded patients with secondary causes of facial palsy. We analyzed the findings of blink reflex according to age, sex, evaluation time, and severity of facial palsy. Results: Of 320 consecutive patients with facial palsy, a total of 204 patients were enrolled. Blink reflex was normal for 10 patients and abnormal for 194 patients. The time interval between the symptom onset and the evaluation time was not associated with the result of blink reflex, but House-Brackmann grade was significantly related to the result of blink reflex (P<0.001). Patients with mild Bell's palsy often showed normal blink reflex. Conclusions: Our study shows that blink reflex is useful diagnostic test regardless of evaluation timing in the early stage of Bell's palsy, although it could be normal in patients with mild Bell's palsy.