• Journal of Korean Neurosurgical Society
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• v.66 no.4
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• pp.382-392
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• 2023

Objective : The use of indocyanine green videoangiography (ICG-VA) to assess blood flow in the brain during cerebrovascular surgery has been increasing. Clinical studies on ICG-VA have predominantly focused on qualitative analysis. However, quantitative analysis numerical modelling for time profiling enables a more accurate evaluation of blood flow kinetics. In this study, we established a multiple exponential modified Gaussian (multi-EMG) model for quantitative ICG-VA to understand accurately the status of cerebral hemodynamics. Methods : We obtained clinical data of cerebral blood flow acquired the quantitative analysis ICG-VA during cerebrovascular surgery. Varied asymmetric peak functions were compared to find the most matching function form with clinical data by using a nonlinear regression algorithm. To verify the result of the nonlinear regression, the mode function was applied to various types of data. Results : The proposed multi-EMG model is well fitted to the clinical data. Because the primary parameters-growth and decay rates, and peak center and heights-of the model are characteristics of model function, they provide accurate reference values for assessing cerebral hemodynamics in various conditions. In addition, the primary parameters can be estimated on the curves with partially missed data. The accuracy of the model estimation was verified by a repeated curve fitting method using manipulation of missing data. Conclusion : The multi-EMG model can possibly serve as a universal model for cerebral hemodynamics in a comparison with other asymmetric peak functions. According to the results, the model can be helpful for clinical research assessment of cerebrovascular hemodynamics in a clinical setting.

• Journal of Periodontal and Implant Science
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• v.53 no.6
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• pp.406-416
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• 2023

Purpose: No evidence exists regarding the advantages of periodontal regeneration treatment for furcation defects using soft block bone substitutes. Therefore, this randomized controlled trial aimed to assess the clinical and radiographic outcomes of regenerative therapy using porcine-derived soft block bone substitutes (DPBM-C, test group) compared with porcine-derived particulate bone substitutes (DPBM, control group) for the treatment of severe class II furcation defects in the mandibular molar regions. Methods: Thirty-five enrolled patients (test group, n=17; control group, n=18) were available for a 12-month follow-up assessment. Clinical (probing pocket depth [PPD] and clinical attachment level [CAL]) and radiographic (vertical furcation defect; VFD) parameters were evaluated at baseline and 6 and 12 months after regenerative treatment. Early postoperative discomfort (severity and duration of pain and swelling) and wound healing outcomes (dehiscence, suppuration, abscess formation, and swelling) were also assessed 2 weeks after surgery. Results: For both treatment modalities, significant improvements in PPD, CAL, and VFD were found in the test group (PPD reduction of 4.1±3.0 mm, CAL gain of 4.4±2.9 mm, and VFD reduction of 4.1±2.5 mm) and control group (PPD reduction of 2.7±2.0 mm, CAL gain of 2.0±2.8 mm, and VFD reduction of 2.4±2.5 mm) 12 months after the regenerative treatment of furcation defects (P<0.05). However, no statistically significant differences were found in any of the measured clinical and radiographic parameters, and no significant differences were observed in any early postoperative discomfort and wound healing outcomes between the 2 groups. Conclusions: Similar to DPBM, DPBM-C showed favorable clinical and radiographic outcomes for periodontal regeneration of severe class II furcation defects in a 12-month follow-up period.

• Journal of Korean Dental Science
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• v.8 no.1
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• pp.16-27
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• 2015

Purpose: The purpose of this study was to evaluate the correlation between the clinical symptoms of temporomandibular disorder and findings in the magnetic resonance imaging (MRI). Materials and Methods: Clinical data and MRI images were collected from a total of 240 German patients. Clinical symptoms were briefed as joint clicking, crepitus and pain. MRI findings were further defined according to the condyle position, condyle degeneration, disc positon, disc degeneration and the presence of osteophyte/sclerosis/synovitis. Hypermobility was separately recorded. Correlation analysis between parameters was performed. Result: Joint clicking had a positive correlation with unilateral disc degeneration, osteophyte, sclerosis and synovitis. Crepitus had a significant correlation with bilateral osteophyte. Pain was not correlated with any MRI findings except hypermobility. Conclusion: Selective correlations between the MRI findings and clinical symptoms were elucidated. The results of this study imply that condyle-disc deformities could be advanced without pain, and that joint clicking and crepitus could be clinical symptoms of condyle-disc degeneration.

• Annals of Clinical Neurophysiology
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• v.19 no.2
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• pp.113-117
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• 2017

The performance of electroencephalogram (EEG) recordings is affected by electrode type, electronic parameters such as filtering, amplification, signal conversion, data storage; and environmental conditions. However, no single method has been identified for optimal EEG recording quality in all situations. Therefore, we aimed to provide general principles for EEG electrode selection as well as electronic noise reduction, and to present comprehensive information regarding the acquisition of satisfactory EEG signals. The standards provided in this document may be regarded as Korean guidelines for the clinical recording of EEG data. The equipment, types and nomenclature of electrodes, and the details for EEG recording are discussed.

• Journal of Biomedical Engineering Research
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• v.26 no.5
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• pp.271-282
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• 2005

There are strong demands for accurate, fast, and inexpensive devices in the medical diagnostic laboratories, such as biosensors and chemical sensors. Biosensors can provide the reliable and accurate informations on the desired biochemical parameters, which is an essential prerequisite for a patient before going for a treatment. They can be used for continuous measurements of metabolites, blood cations, gases, etc. Of these, electrochemical biosensors play an important role in the improvement of public health, because rapid detection, high sensitivity, small size, and specificity are achievable for clinical diagnostics. In this paper, the clinical applications with electrochemical biosensors are reviewed. An attempt is also made to highlight some of the trends that govern the research and developments of the important biosensors that are associated to clinical diagnosis.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.1
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• pp.167-182
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• 2010

Objectives : The purpose of this study is to find correlation about 7-Zone-Diagnostic System and Clinical Parameters using Oriental Health Examination. Methods : Subjects of our study were 325 cases who took Oriental Health Examination. We collected the data of body composition analysis, 7-Zone-Diagnostic System, blood analysis and devided by 7-Zone-Diagnostic system to acceleration, normalcy and depression. Results and Conclusions : The values of muscle mass, body fat mass, abdomen obesity rate, right arm water index, left arm water index, trunk water index, right leg water index, left leg water index, BMI, BMR, GOT, GPT, ${\gamma}$-GTP, BUN, TC, triglyceride and hemoglobin were continuous with 7-Zone-Diagnostic system.

• Journal of Biomedical Engineering Research
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• v.13 no.4
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• pp.299-306
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• 1992

For quantitative measurement of reflected light from a clinical diagnostic scrip, a prototype of reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate re(leclance parameters. The strop was illuminated at $45^{\circ}C$ through optical fiber and the intensity of reflected light was determined at rectangulat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500,550,570 and 610nm) for blood glucose strip. For higher concentration than 300mg/dl about glucose, a saturation state of absorbance was observed at 500,550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm.

• Journal of Biomedical Engineering Research
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• v.17 no.2
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• pp.155-164
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• 1996

In the clinical environment, measurements of some characteristics of the skeletal muscle are currently used to assess the severity of a neuromuscular disease or in some cases to assist in making a diagnosis. But a quantitative method of evaluation has not yet been introduced satisfactorily. In this paper, the skeletal EMG(biceps muscle, masseter muscle) analysis has been processed both in the time and in the frequency domain by designing the digital signal processing system based on pentium PC and transputer (IMS 7805). The experiment have been performed in five normal subjects, and various parameters have been statistically tested and compare4 As a results, the effective parameters obtained for the evaluation of skeletal EMG electrical activity are turn analysis, MiTi, MiTa, IEMG, PDF in the time domain, and are mean frequency, median frequency, skewness, kurtosis, muscle fatigue slope in the frequency domain. The designed H/W and S/W in this study can be used effectively for the establishment of EMG data base and for clinical research.

• Korean Journal of Clinical Laboratory Science
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• v.40 no.1
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• pp.18-25
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• 2008

In classical titrimetric analyses, the major concern is the concentration of titrant, usually the aqueous solution of hydrochloric acid or sodium hydroxide, that could be changed as time goes by and it is accompanied with the inaccuracy of the resulting data. And the statistical approach, the nonlinear regression analysis, which is a well-known statistical method, was introduced to determine the accurate concentration of the titrant and the exact value of parameters, $K_a$, r, $C_a$, $C_b$, for 0.01 M aqueous solutions of analytes, sodium pyruvate, sodium acetate, sodium bicarbonate, ammonium hydroxide, ammonium chloride and acetic acid at $25^{\circ}C$. We used Gauss-Newton method for the linearlization of the nonlinear titration system and the two-parameter fitting showed appreciable convergent data for the parameters of the analytes set with the various range of $K_a$ value.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.6
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• pp.588-593
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• 2019

This study aimed to report three new cases of an association between two rare conditions, congenital portosystemic shunts (CPSS) and trimethylaminuria (TMAU), and the efficacy of endovascular closure of the CPSS for resolving TMAU. Between November 2014 and April 2017, 15 patients with CPSS were enrolled in this prospective study to assess the efficacy of percutaneous endovascular shunt closure. Three patients presented with clinical symptoms of TMAU that were confirmed by urine analysis of trimethylamine (TMA) and TMA n-oxide. One year after endovascular closure of the congenital portosystemic shunt, the same parameters were evaluated were obtained and the values were compared to the pretreatment values. The results indicated the disappearance of clinical symptoms of TMAU and normalization of the urine test parameters in two patients and no changes in one patient, who developed new portosystemic communications.