No abstract available.

BACKGROUND: In discography performed during percutaneous endoscopic lumbar discectomy (PELD) via the posterolateral approach, it is difficult to create a fluoroscopic tunnel view because a long needle is required for discography and the guide-wire used for consecutive PELD interrupts rotation of fluoroscope. A stereotactic system was designed to facilitate the determination of the needle entry point, and the feasibility of this system was evaluated during interventional spine procedures. METHODS: A newly designed stereotactic guidance system underwent a field test application for PELD. Sixty patients who underwent single-level PELD at L4-L5 were randomly divided into conventional or stereotactic groups. PELD was performed via the posterolateral approach using the entry point on the skin determined by premeasured distance from the midline and angles according to preoperative magnetic resonance imaging (MRI) findings. Needle entry accuracy provided by the two groups was determined by comparing the distance and angle measured by postoperative computed tomography with those measured by preoperative MRI. The duration and radiation exposure for determining the entry point were measured in the groups. RESULTS: The new stereotactic guidance system and the conventional method provided similarly accurate entry points for discography and consecutive PELD. However, the new stereotactic guidance system lowered the duration and radiation exposure for determining the entry point. CONCLUSIONS: The new stereotactic guidance system under fluoroscopy provided a reliable needle entry point for discography and consecutive PELD. Furthermore, it reduced the duration and radiation exposure associated with determining needle entry.
Diskectomy ; Diskectomy, Percutaneous ; Equipment Design ; Fluoroscopy ; Humans ; Magnetic Resonance Imaging ; Needles ; Skin ; Spine ; Stereotaxic Techniques

The aim of this study was to determine if a 457 nm blue laser could effectively polymerize dental composite resins. After light curing 6 dental composite resins using a laser or a LED light-curing unit at 530 mW/cm2 and 900 mW/cm2, respectively, degree of conversion and microhardness were evaluated. Degree of conversion of specimens by the laser and LED was similar (on top surface 54.4–67.7% and 55.2–67.1%, respectively; on bottom surface 35.1–53.8% and 45.4–53.1%, respectively). Microhardness was also similar (on top surface 28.5–83.6 Hv and 19.1–82.4 Hv, respectively; on bottom surface 22.5–65.4 Hv and 16.8–74.4 Hv, respectively), although, in some cases, laser-treated specimens showed slightly lower microhardness than the LED-treated on bottom surface. The present study shows that the 457 nm laser can polymerize dental composite resins to the same level as LED achieved.
Composite Resins ; Polymerization ; Polymers

OBJECTIVE: In general, quadriplegic patients use their voices to call the caregiver. However, severe quadriplegic patients are in a state of tracheostomy, and cannot generate a voice. These patients require other communication tools to call caregivers. Recently, monitoring of eye status using artificial intelligence (AI) has been widely used in various fields. We made eye status monitoring system using deep learning, and developed a communication system for quadriplegic patients can call the caregiver. METHODS: The communication system consists of 3 programs. The first program was developed for automatic capturing of eye images from the face using a webcam. It continuously captured and stored 15 eye images per second. Secondly, the captured eye images were evaluated for open or closed status by deep learning, which is a type of AI. Google TensorFlow was used as a machine learning tool or library for convolutional neural network. A total of 18,000 images were used to train deep learning system. Finally, the program was developed to utter a sound when the left eye was closed for 3 seconds. RESULTS: The test accuracy of eye status was 98.7%. In practice, when the quadriplegic patient looked at the webcam and closed his left eye for 3 seconds, the sound for calling a caregiver was generated. CONCLUSION: Our eye status detection software using AI is very accurate, and the calling system for the quadriplegic patient was satisfactory.
Artificial Intelligence ; Caregivers ; Humans ; Learning ; Machine Learning ; Quadriplegia ; Tracheostomy ; Unsupervised Machine Learning ; Voice

Although various animals have been used as models of cardiac valvular diseases in humans, the structural characteristics of cardiac valves in animals remain unclear. In this study, we investigated cardiac valves in representative animal models for the purpose of comparative anatomy. Adult hearts from three dogs, four goats, six rabbits, and six fowls were fixed with 10% neutral-buffered formalin and analyzed gross-anatomically. Cardiac appearance was spherical or oval in dogs, goats, and rabbits, whereas it had a long conical shape in fowls. Left atrioventricular (AV) valve was composed of membranous septal and parietal cusps connected to two papillary muscles in all animals. The right AV valve was composed of membranous septal, parietal, and angular cusps with three papillary muscles in dogs and goats, membranous septal and parietal cusps attached to four papillary muscles in rabbits, and a single muscular plate without any papillary muscles and chorda tendinae in fowls. Aortic valves with thin membranous right, left, and septal semilunar cusps in dogs, goats, and rabbits had a thick membrane with a bended free border in fowls. Pulmonary valve (PV) with membranous right, left, and intermediate semilunar cusps made a large central hole by being closely attached to the surrounding wall in dogs, goats, and rabbits, whereas it protruded into half of the lumen as a thick membrane in fowls. The membranous cusp of the PV was composed of several layers in dogs and goats but was a single layer in rabbits and fowls. These findings indicate that even if animals have two completely separated atria and ventricles each, cardiac valves have species-specific morphological characteristics, especially between mammals and fowls.
Adult ; Anatomy, Comparative ; Animals ; Aortic Valve ; Dogs ; Formaldehyde ; Goats ; Heart ; Heart Valves* ; Humans ; Mammals ; Membranes ; Models, Animal ; Papillary Muscles ; Pulmonary Valve ; Rabbits ; Rabeprazole

PURPOSE: A carcinoma of the ampulla of Vater has more favorable prognosis than other malignant tumors of the periampullary region, because it is symptomatic at an early stage. However, local resection of an ampullary carcinoma remains controversial. The aim of this study was to evaluate the treatment results of ampulla of Vater carcinomas, according to operation type in low risk group patients. METHODS: The records of 17 low risk group patients, among 120 patients with ampulla of Vater cancer, who underwent curative surgery beyween 1992 and 2002, were reviewed. All specimens were critically reviewed by a single expert pathologist. The relationship between surgical outcomes and operation type were assessed. RESULTS: There were 10 men and 7 women, with a median age of 57.8 years. 13 of the 17 patients underwent the Whipples operation or a PPPD, and 4 underwent a transduodenal local resection (TDLR). The operation time was shorter in the TDLR group, and was statistically significant. Among the 17 patients, only one had a recurrence in the inguinal area 33 months after the PD. CONCLUSION: Transduodenal local resection is a recommendable operation for low risk Ampulla of Vater cancer patients. During the operation, it is essential to accurately evaluate the depth of invasion, cell differentiation and positivity of the resection margin using frozen sections.
Ampulla of Vater* ; Cell Differentiation ; Female ; Frozen Sections ; Humans ; Male ; Prognosis ; Recurrence

BACKGROUND: The purpose of this study was to assess the intra-articular patterns in the rotational deformities of bucket handle meniscal tears (BHMTs) based on arthroscopic findings and their clinical relevance. METHODS: From 2004 to 2009, 42 patients with a BHMT diagnosed by magnetic resonance imaging underwent arthroscopic surgery. The arthroscopic data (all procedures were recorded) were evaluated retrospectively, and BHMTs were classified according to the rotational directions of centrally displaced fragments. To assess the reliability of the agreement in this classification, 2 orthopedic surgeons re-classified BHMTs, 1 week after first trial. Intra- and interobserver reliabilities were assessed using kappa statistics. In addition, we address specific tear patterns, associated anterior cruciate ligament injury, medio-lateral difference, reducibility, chronicity, and reparability. RESULTS: Most of the tears could be categorized into one of 3 morphologic patterns. Of the tears, 4.8% could not be categorized. BHMTs were classified, based on the rotational directions of centrally displaced fragments, as follows; the upward rotation group (type 1), the downward rotation group (type 2) and the reverse group (type 3). The most common intra-articular pattern was type 1 (29 patients, 69%). The occurrence of the other patterns was: type 2 in 7 patients (16.7%), type 3 in 4 patients (9.5%); we were not able to make a classification of type in 2 patients (4.8%). Intra-observer reliability was 0.86 in terms of kappa statistics, which implies almost perfect agreement. Mean interobserver reliability (0.73) showed substantial agreement. Type 1 and 2 tears were easily reduced, whereas all type 3 tears (4/4) needed additional procedures to achieve reduction. CONCLUSIONS: Based on arthroscopic findings, we describe a comprehensive BHMT classification scheme that encompasses 95.2% of all tears. Tear type was correlated with reducibility.
Adolescent ; Adult ; Anterior Cruciate Ligament/*injuries/pathology/surgery ; Arthroscopy/*methods ; Female ; Humans ; Knee Injuries/classification/*pathology/surgery ; Magnetic Resonance Imaging ; Male ; Menisci, Tibial/*injuries/pathology/surgery ; Middle Aged ; Reproducibility of Results ; Retrospective Studies

BACKGROUND: Delapril, a recently developed nonsulfhydry(SH) angiotensin converting enzyme inhibitor, was known to have more prolonged duration of action. In order to investigate the efficacy and safety of delapril, patients with essential hypertension were studied. METHODS: The study subject consisted of 37 patients(mean age : 50.4 years, 15 male, 22 female). Because 4 of 37 patients dropped out due to side effects of delapril, the antihypertensive efficacy was evaluated in the remaining 33 patients. Delapril was administered orally in a daily dose of 30-120mg in two divided doses for 10 weeks after the administration of a placebo for 2 weeks. RESULTS: Delapril decreased systolic blood pressure significantly from a baseline value of 162.4+/-18.8mmHg to 142.9+/-20.9mmHg(p<0.01) and diastolic blood pressure from 103.2+/-5.0mmHg to 92.8+/-10.4mmHg(p<0.01) after 2 weeks of therapy, and maintained this effect throughout the study period. The efficacy rates were 72% for systolic pressure, 75% for diastolic pressure. The cumulative efficacy rate was 48% at 30mg/day, 66% at 60mg/day, and 73% at 120mg/day. Heart rate did not change until after 8 weeks, when they modestly decreased(p<0.05), through the 10th week(NS). Side effects were noticed in 12 out of 37 cases(32.4%). The main symptoms included dry cough(7 cases, 18.9%), headache(2 cases, 5.4%), dizziness(1 case, 2.7%), dry mouth(1 case, 2.7%) and angioedema(1 case, 2.7%). Six of the 7cases of dry cough were in women, and 3 caes discontinued the drug due to intractable cough. Angioedema in the oropharynx occurred in 1 patient and caused severe dyspnea which was relieved by the discontinuation of the medication. There was no significant change in CBC and biochemical variables. CONCLUSIONS: A daily dose of delapril in two divided doses is effective in decreasing blood pressure in patients with essential hypertension, and safe when an awareness of possible side effects is taken into account.
Angioedema ; Blood Pressure ; Cough ; Dyspnea ; Female ; Heart Rate ; Humans ; Hypertension* ; Male ; Oropharynx ; Peptidyl-Dipeptidase A

OBJECTIVES: To investigate the role of ATP-sensitive potassium channel (KATP) during sustained ventricular fibrillation (VF), the effects of gliburide, a specific blocker of KATP channel and PCO400, an KATP opener, were studied in isolated and perfused swine right ventricular free walls (n=). METHODS: Recording of single cell transmembrane potentials was performed and constructed action potential duration restitution (APDR) curve by plotting APD 90%(APD90) versus preceding diastolic interval (DI). RESULTS: All isolated tissues fibrillated spontaneously. In this preparation, stable VF could persist over a 4-hour period if it was allowed to continue undisturbed (n=). Gliburide (1-5 uM) increased DI without significant changes in APD90 during VF, resulting in more regularization of VF. Higher concentration (10-20 uM) increased both APD90 and DI, and converted to monomorphic ventricular tachycardia (MVT) through the transitional period characterized by APD alternans. PCO400 (1-2.5 uM) caused a significant shortening of APD during MVT and a period of APD alternans became more evident before conversion from MVT to VF. Gliburide eliminated profibrillatory effect of PCO400. This antifibrillatory action of gliburide was accompanied by gradual decrease in the maximum slope of APDR curve during VF. CONCLUSION: KATP channel blockade causes a transition from VF to MVT via lengthening of DI and APD alternans, concomitantly with a reduction of the slope of APD restitution curve.
Action Potentials ; Membrane Potentials ; Potassium Channels ; Swine ; Tachycardia, Ventricular ; Ventricular Fibrillation*

BACKGROUND/AIMS: Laparoscopic cholecystectomy has become popular. Occasionally, unsuspected gallbladder carcinoma is diagnosed after the operation by pathologic examination, incidentally. And even when the gallbladder carcinoma is suspected preoperatively, it is determined whether or not the additional radical operation will proceed, according to the pathologic diagnosis after laparoscopic cholecystectomy. Multiple staging systems have been described, including the modified Nevin classification (Donohue et al 1990, Nevin et al 1976), the AJCC TNM staging system, and there are controversies in the surgical management of gallbladder carcinoma for each stage. The purpose of this study was to evaluate the role and the meaning of the laparoscopic cholecystectomy in the surgical management of the gallbladder carcinoma. METHODS: A retrospective analysis was made of 24 patients with gallbladder carcinoma that was confirmed by pathologic diagnosis after laparoscopic cholecystectomy in Severance Hospital between January 1993 and Feburary 2002. RESULTS: Gallbladder carcinoma was found in 1.1% of the 2141 cholecystectomy specimens. Gallbladder carcinoma was suspected preoperatively in 11 patients (45.8%). The location of the lesions was the serosal side in 16 patients (66.7%), the liver bed side in 1 patient, and undetermined in 7 patients. The histologic type was adenocarcinoma in all patient, and well differentiated in 16 patients (66.7%), moderate and poorly differentiated in 8 patients (33.3%). According to the AJCC TNM staging system, there were 13 stage I (54%), 5 stage II (20.8%), 2 stage III (8.3%), 4 stage IV (16.7%). The lymph node metastasis was observed in 4 patients (16.7%). In 18 patients (75%), only laparoscopic cholecystectomies were performed, and additional radical cholecystectomies were performed in 4 patients (16.7%). The patients with stage I and II tumor were alive without recurrence except 1 follow-up loss, and there was not any port site recurrence. CONCLUSION: Laparoscopic cholecystectomy is sufficient with stage I gallbladder carcinoma. It may be considered that the patient with stage II gallbladder carcinoma is closely followed without additional radical cholecystectomy after laparoscopic cholecystectomy, if properly selected. The use of vinyl bag for retrieval of specimen is recommended to avoid the port site recurrence. For advanced gallbladder carcinoma (stage III and IV), the additional radical cholecystectomy is recommended. When gallbladder cancer is suspected, an open operation should be performed with sufficient preoperative staging work-up.
Adenocarcinoma ; Cholecystectomy ; Cholecystectomy, Laparoscopic* ; Classification ; Diagnosis ; Follow-Up Studies ; Gallbladder Neoplasms ; Gallbladder* ; Humans ; Liver ; Lymph Nodes ; Neoplasm Metastasis ; Neoplasm Staging ; Recurrence ; Retrospective Studies