BACKGROUND: Exercise has shown to slow down the progression from mild cognitive impairment (MCI) to dementia. In particular, not only resistance exercise has been verified to improve physical performance and muscle strength, leading to the prevention of fall-related injuries in the frail elderly, but also cognitive function. In this study, we investigated how high-speed elastic band training, applied using a high-speed power training protocol, affects cognition, physical performance and muscle strength of female elderly individuals with MCI. METHODS: Thirty-nine subjects diagnosed with MCI from one senior college using a Korean version of mini-mental state examination (MMSE-K) and a Korean version of the Montreal Cognitive Assessment (MoCA-K) were randomly divided into exercise group (n=20) and control group (n=19). The exercise group completed a 12-week high-speed resistance elastic band exercise program and was encouraged to exercise at home as well during the intervention period. RESULTS: The results showed significant increases in cognitive function, physical performance and muscle strength assessed by digit span forward test (P<0.001), digit span backward test (P=0.003), the Stroop test B (P=0.031), SPPB scores (P=0.010), right knee 60degrees extensor peak torque (P=0.004), 60degrees flexor peak torque (P=0.001), 180degrees extensor peak torque (P=0.020) and grip strength (P=0.025). CONCLUSIONS: Our study showed that participants with MCI who continued the high-speed elastic band training program for 12 weeks showed improvements in cognitive function, physical performance and muscle strength.
Aged ; Cognition ; Dementia ; Education ; Female ; Frail Elderly ; Hand Strength ; Humans ; Knee ; Mild Cognitive Impairment* ; Muscle Strength* ; Resistance Training ; Stroop Test ; Torque

Purpose: To compare the polishing characteristics and their influence on Candida albicans adhesion to the recently introduced polyetherketoneketone (PEKK) and the conventional polymethylmethacrylate (PMMA) denture resin material. Materials and methods: Specimens from PEKK (Group E) and PMMA (Group M) were made in dimensions of 8 mm in diameter and 2 mm in thickness. The specimens were further divided into sub-groups according to the extent of polishing (ER, MR: rough; EP, MP: polished, N = 12 each). The specimens were polished using polishing machine and SiC foil. ER and MR group specimens were polished with 600 grit SiC foil only. EP and MP groups were further polished with 800, 1,000, 1,200 grit SiC foils sequentially. To measure the surface roughness values (Sa) of specimens, atomic force microscope (AFM) was used and scanning electron microscope (SEM) observation under 1,000, and 20,000 magnifications was performed to investigate surface topography. The polished specimens were soaked in C. albicans suspension for 2 hours with shaking to promote adhesion. The attached C. albicans were detached from the surface with 10 times of pipetting. The suspension of detached C. albicans was performed by serial dilution to 103 times, and the diluted suspensions were inoculated on Sabouraud dextrose agar plates using spread plate method. After incubating the plate for 48 hours, colony forming unit (CFU)/plate of C. albicans was counted. Statistical analysis was performed using one-way ANOVA and Tukey HSD test to confirm significant difference between the groups (α=.05). Results: Average Sa value was significantly higher in MR group compared to other groups (P<.05), meaning that additional polishing steps reduced surface roughness effectively only in the PMMA specimens. There was no significant difference in Sa values between MP and EP groups. In SEM images, PEKK specimens showed numerous spikes of abraded material protruding from the surface and this phenomenon was more significant in EP group. The mean CFU/plate value was the highest in EP group and this was significant when it was compared to MP group (P<.05) which was the lowest. Conclusion Polishing PEKK using serial SiC abrasive foil may result in higher adhesion of C. albicans. In clinic, this should be considered carefully.

Malignant salivary gland tumor is rare neoplasm. In Korean population, retrospective study of malignant salivary gland tumor has not been performed. We analyzed 67 cases of malignant salivary gland tumors from 2001 to 2005 in Seoul National University Dental Hospital in Seoul, Korea. The mean age is 51.7 and the male to female ratio is 1:1.39. The most affected site is the palate. Histologically, the tumors were classified as adenoid cystic carcinoma(34.4%), mucoepidermoid carcinoma(31.3%), adenocarcinoma, NOS(11.9%), polymorphous low grade adenocarcinoma(3.0%), salivary duct carcionoma(6.0%), carcinoma ex pleomorphic adenoma(4.5%), myoepithelial carcinoma(4.5%), epithelial-myoepithelial carcinoma(1.5%), cyatadenocarcinoma(1.5%) and adenosquamous carcinoma(1.5%).
Adenocarcinoma ; Adenoids ; Female ; Humans ; Korea ; Male ; Palate ; Retrospective Studies ; Salivary Ducts ; Salivary Glands* ; Seoul

BACKGROUND/AIMS: Hepatic cysts are incidentally found at laparotomy or through abdominal imaging studies. When they become symptomatic, treatment is indicated. The aim of this study is to evaluate many options of their management, especially about surgical methods. METHODS: Data were retrospectively analyzed from the clinical charts of 21 patients undergoing surgery for symptomatic hepatic cysts from January, 1995, through December, 2002 in department of Surgery, Pusan University Hosipital. Charts were obtained from the original hosipital referral. We considered the following variables for analysis: age, sex, symptoms, hepatic cyst location, size, operative methods, histological confirm, postoperative morbidity and mortality, length of postoperative hosipital stay, and follow-up outcome. RESULTS: Mean age of the 21 patients was 53 years. The ratio of male and female was 1:4.3. Their main symptoms were right upper quadrant pain or discomfort, epigastric pain, and abdominal distension. Rarely, palpable mass, dyspepsia, mild jaundice, and acute abdominal pain from ruptured hepatic cyst were observed. Preoperative abdominal ultrasound and computed tomographic scannig were done in all patients. The mean size of hepatic cysts was 9.04 cm in computed tomographic scanning. The 61.9% of patients had the location in right lobe. Simple cyst was characterized by homogeneous, low attenuated and unilocular mass in computed tomographic scanning: in difference, biliary cystadenoma, internal intervening septation and papillary infoldings with cyst itself. Fifteen patients underwent partial cystectomy and 4, complete cystectomy and 1, non-anatomical hepatic resection and 1, left lateral segmentectomy. Hepatic cysts were consisting of 15 cases of simple cyst, 4 cases of biliary cystadenoma, 1 case of Caroli's disease and 1 case of polycystic liver disease. Postoperative complication was bile leakage in one case. No symptomatic recurrence occured during a mean follow-up period of 42.5 months. CONCLUSION: According to the characteristics of symptomatic hepatic cyst, proper operative methods of management were considered. More long-term follow-up is necessary but in simple cyst in histological type, partial cystectomy can be the acceptable technique, complete cystectomy or hepatic resection should be perfomed in biliary cystadenoma for recurrence and malignant potential.
Abdominal Pain ; Bile ; Busan ; Caroli Disease ; Cystadenoma ; Cystectomy ; Dyspepsia ; Female ; Follow-Up Studies ; Humans ; Jaundice ; Laparotomy ; Liver Diseases ; Male ; Mastectomy, Segmental ; Mortality ; Postoperative Complications ; Recurrence ; Referral and Consultation ; Retrospective Studies ; Ultrasonography

OBJECTIVES: Augmented reality (AR) technology has become rapidly available and is suitable for various medical applications since it can provide effective visualization of intricate anatomical structures inside the human body. This paper describes the procedure to develop an AR app with Unity3D and Vuforia software development kit and publish it to a smartphone for the localization of critical tissues or organs that cannot be seen easily by the naked eye during surgery. METHODS: In this study, Vuforia version 6.5 integrated with the Unity Editor was installed on a desktop computer and configured to develop the Android AR app for the visualization of internal organs. Three-dimensional segmented human organs were extracted from a computerized tomography file using Seg3D software, and overlaid on a target body surface through the developed app with an artificial marker. RESULTS: To aid beginners in using the AR technology for medical applications, a 3D model of the thyroid and surrounding structures was created from a thyroid cancer patient's DICOM file, and was visualized on the neck of a medical training mannequin through the developed AR app. The individual organs, including the thyroid, trachea, carotid artery, jugular vein, and esophagus were localized by the surgeon's Android smartphone. CONCLUSIONS: Vuforia software can help even researchers, students, or surgeons who do not possess computer vision expertise to easily develop an AR app in a user-friendly manner and use it to visualize and localize critical internal organs without incision. It could allow AR technology to be extensively utilized for various medical applications.
Carotid Arteries ; Education, Medical ; Esophagus ; Human Body ; Humans ; Imaging, Three-Dimensional ; Jugular Veins ; Manikins ; Methyltestosterone ; Neck ; Smartphone ; Surgeons ; Thyroid Gland ; Thyroid Neoplasms ; Thyroidectomy ; Trachea

Purpose: To evaluate the clinical reliability of the Topolyzer Vario (Wavelight-Alcon, Erlangen, Germany), we compared threedifferent corneal topographers in terms of corneal refractive power. Methods: The medical records of patients who visited Severance Hospital for corneal refractive surgery were retrospectivelyreviewed. Keratometric data of patients who underwent evaluations using the Pentacam HR (Oculus, Wetzlar, Germany),ORBscan II (Bausch & Lomb, Rochester, NY, USA), and Topolyzer Vario instruments on the same day were obtained. Flat keratometry(Kf), steep keratometry (Ks), mean keratometry (Km), astigmatism keratometry (Kastig), Cartesian astigmatism (J0), andoblique astigmatism (J45) values were calculated. The measurement values of the three devices were subjected to Pearson’scorrelation analysis and repeated measures analysis of variance (with Bonferroni correction); a Bland-Altman plot was alsocreated. Results: The keratometric data of 80 eyes were included in the analysis and all of the keratometric measurements obtained bythe three devices showed significant correlations, i.e., good agreement. The Kf and Km measurements of the Pentacam HR wereflatter than those of the ORBscan II, and the Kf, Km, Ks, and J45 measurements were flatter than those of the Topolyzer Vario.However, there was no significant difference in keratometric values between the ORBscan II and Topolyzer Vario. Furthermore,the difference in corneal refractive power between the Pentacam HR and Topolyzer Vario was not clinically significant. Conclusions When measuring the corneal refractive power of patients without any history of corneal disorder or ocular surgery,the Topolyzer Vario is a clinically reliable device that shows similar performance to the ORBscan II and Pentacam HR.

PURPOSE: Increased robotic surgery is attended by increased reports of complications, largely due to limited operative view and lack of tactile sense. These kinds of obstacles, which seldom occur in open surgery, are challenging for beginner surgeons. To enhance robotic surgery safety, we created an augmented reality (AR) model of the organs around the thyroid glands, and tested the AR model applicability in robotic thyroidectomy. METHODS: We created AR images of the thyroid gland, common carotid arteries, trachea, and esophagus using preoperative CT images of a thyroid carcinoma patient. For a preliminary test, we overlaid the AR images on a 3-dimensional printed model at five different angles and evaluated its accuracy using Dice similarity coefficient. We then overlaid the AR images on the real-time operative images during robotic thyroidectomy. RESULTS: The Dice similarity coefficients ranged from 0.984 to 0.9908, and the mean of the five different angles was 0.987. During the entire process of robotic thyroidectomy, the AR images were successfully overlaid on the real-time operative images using manual registration. CONCLUSION: We successfully demonstrated the use of AR on the operative field during robotic thyroidectomy. Although there are currently limitations, the use of AR in robotic surgery will become more practical as the technology advances and may contribute to the enhancement of surgical safety.
Carotid Artery, Common ; Esophagus ; Humans ; Robotic Surgical Procedures ; Surgeons ; Thyroid Gland* ; Thyroid Neoplasms ; Thyroidectomy ; Trachea

Objective: To evaluate the reliability of suprahyoid and infrahyoid electromyography (EMG) measurement during swallowing. Methods: In all, 10 healthy volunteers were evaluated for the following surface EMG (sEMG) parameters in the suprahyoid and infrahyoid muscles during swallowing: onset latency, offset latency, duration, peak latency, maximal amplitude during swallowing, and the area under curve (AUC) of the rectified EMG signal. The sEMG was recorded while the participants swallowed five times each of the four fluid volumes (saliva, 2 ml, 5 ml, and 20 ml of water), totaling to 20 swallows. Moreover, the intra-participant variability per parameter was evaluated using the coefficient of variation (CV). Results: Suprahyoid muscles were activated 0.095 s (95% CI, 0.062-0.128) earlier than the infrahyoid muscles.Maximal amplitudes during the 20 ml swallow were 17.484 (−1.543-36.512) and 13.490 (1.254-25.727) μV higher than values obtained during the 2 ml swallow in the suprahyoid and infrahyoid muscles, respectively. Furthermore, the AUC of the rectified EMG signal increased with the volume of swallow in both muscle groups (P=0.003, suprahyoid; P＜0.002, infrahyoid). The intra-individual variabilities of offset latency, duration, and maximal amplitude were relatively low (＜30% CV) in both muscle groups with respect to other parameters. The assessment of each parameter using EMG was highly reliable, with an intraclass correlation coefficient of ＞0.8. Conclusion Among the variable sEMG parameters assessed, the offset latency, duration, and maximal amplitude were the least variable. Although reliability on the rater side showed good results, the swallow-to-swallow variability of the parameters need to be considered in swallowing studies using sEMG.

Objective: To evaluate the reliability of suprahyoid and infrahyoid electromyography (EMG) measurement during swallowing. Methods: In all, 10 healthy volunteers were evaluated for the following surface EMG (sEMG) parameters in the suprahyoid and infrahyoid muscles during swallowing: onset latency, offset latency, duration, peak latency, maximal amplitude during swallowing, and the area under curve (AUC) of the rectified EMG signal. The sEMG was recorded while the participants swallowed five times each of the four fluid volumes (saliva, 2 ml, 5 ml, and 20 ml of water), totaling to 20 swallows. Moreover, the intra-participant variability per parameter was evaluated using the coefficient of variation (CV). Results: Suprahyoid muscles were activated 0.095 s (95% CI, 0.062-0.128) earlier than the infrahyoid muscles.Maximal amplitudes during the 20 ml swallow were 17.484 (−1.543-36.512) and 13.490 (1.254-25.727) μV higher than values obtained during the 2 ml swallow in the suprahyoid and infrahyoid muscles, respectively. Furthermore, the AUC of the rectified EMG signal increased with the volume of swallow in both muscle groups (P=0.003, suprahyoid; P＜0.002, infrahyoid). The intra-individual variabilities of offset latency, duration, and maximal amplitude were relatively low (＜30% CV) in both muscle groups with respect to other parameters. The assessment of each parameter using EMG was highly reliable, with an intraclass correlation coefficient of ＞0.8. Conclusion Among the variable sEMG parameters assessed, the offset latency, duration, and maximal amplitude were the least variable. Although reliability on the rater side showed good results, the swallow-to-swallow variability of the parameters need to be considered in swallowing studies using sEMG.

BACKGROUND: Aging related decrease in muscle strength and flexibility leads to functional loss of physical ability. Power training is known to improve these capacities and helps in performing daily routine better. Therefore, we modified previously proven and certified sarcopenia intervention exercise for elderly in rural community and applied them to examine the effects on physical fitness and muscle functions to show its applicability. METHODS: Subjects were divided into control and exercise group using single-blind method. Exercise group underwent high-speed elastic band training(concentric contraction in 1 second) 2 days per week for 12 weeks. Before and after the intervention, we performed body composition analysis, anthropometric measurement, blood test, blood pressure check, senior fitness test (SFT), upper body and lower body strength examination. Korean version of Physical Activity Scale for the Elderly (K-PASE), and Center for Epidemiological Studies- Depression Scale (CES-D) were also assessed. RESULTS: Body weight in control group was significantly increased (Paired t-test: P=0.008), although it was consistent in exercise group (GroupxTime: P=0.013). 30-second chair stand (P<0.001) and 30-second arm curl (P<0.001) of the senior fitness test were also significantly improved in exercise group compared to control. In addition, muscle strength of knee flexion (P=0.034) and K-PASE score (P<0.001) were improved in training group with statistical significance. CONCLUSIONS: The modified high-speed elastic band training for rural elderly improved muscle strength and daily physical performance. This result suggests a simple and easy to perform band training could be an excellent solution to prevent sarcopenia in rural elderly. It also supports the evidence that this program would be widely distributed.
Aged* ; Aging ; Arm ; Blood Pressure ; Body Composition ; Body Weight ; Depression ; Hematologic Tests ; Humans ; Knee ; Motor Activity ; Muscle Strength ; Physical Fitness* ; Pliability ; Rural Population ; Sarcopenia ; Single-Blind Method