• The Korean Journal of Pain
• /
• v.29 no.1
• /
• pp.57-61
• /
• 2016

Foraminal or extraforaminal Far Lateral Disc Herniations (FLDH) extending into or beyond the foraminal zone have been recognized as between 7-12% of all lumbosacral disc herniations. Conventional posterior laminectomy may not provide good access to a herniation that lies far lateral to the lateral margin of the pedicle. Use of the endoscopic technique through a percutaneous approach to treat such FLDH patients can decrease the surgical morbidity while achieving better outcomes. We made an effort to utilize the advantages of percutaneous endoscopic lumbar discectomy (PELD) and to determine the appropriate approach for FLDH at the level between the 5th Lumbar and first Sacral vertebrae(L5-S1). The authors present a case of an endoscopically resected lumbar extruded disc of the left extraforaminal zone with superior foraminal migration at the level of L5-S1, which had led to foot drop, while placing the endoscope in the anterior epidural space without facetectomy.

• Geophysics and Geophysical Exploration
• /
• v.5 no.1
• /
• pp.18-22
• /
• 2002

As a single arrival traveltime, maximum energy arrival traveltime has been known as the most proper operator for Kirchhoff migration. In case of the model having the simple structure, both the first arrival traveltime and the maximum energy arrival traveltime can be used as the correct operators for Kirchhoff migration. However for some model having the complex and high velocity contrast structure, the migration using the first arrival traveltime can't give the correct depth section. That is, traveltime to be required in Kirchhoff migration is the maximum energy traveltime, but, needs considerably more calculation time than that of first arrival. In this paper, we propose the method for calculating the traveltime approximated to the maximum energy arrival using one-way wave equation. After defining the WAS(Wrap Around Suppression) factor to be used for calculating the first arrival traveltime using one-way wave equation as the function of lateral grid interval and depth and considering the delay time of source wavelet. we calculate the traveltime approximated to the maximum energy arrival. to verify the validity of this traveltime, we applied this to the migraion for simple structure and complex structure and compared the depth section with that obtained by using the first arrival traveltime.

• Hip & pelvis
• /
• v.30 no.4
• /
• pp.254-259
• /
• 2018

Purpose: Internal fixation using compression hip screws (CHS) and traction tables placing patients in the supine position is a gold standard option for treating intertrochanteric fractures; however, at our institution, we approach this treatment with patients in a lateral decubitus position. Here, the results of 100 consecutive elderly (i.e., ${\geq}45$ years of age) patients who underwent internal fixation with CHS in lateral decubitus position are analyzed. Materials and Methods: Between March 2009 and May 2011, 100 consecutive elderly patients who underwent internal fixation with CHS for femoral intertrochanteric fracture were retrospectively reviewed. Clinical outcomes (i.e., Koval score, Harris hip score [HHS]) and radiographic outcomes (i.e., bone union time, amount of sliding of lag screw, tip-apex distance [TAD]) were evaluated. Results: Clinical assessments revealed that the average postoperative Koval score decreased from 1.4 to 2.6 (range, 0-5; P<0.05); HHS was 85 (range, 72-90); and mean bone union time was 5.0 (range, 2.0-8.2) months. Radiographic assessments revealed that anteroposterior average TAD was 6.95 (range, 1.27-14.63) mm; lateral average TAD was 7.26 (range, 1.20-18.43) mm; total average TAD was 14.21 (range, 2.47-28.66) mm; average lag screw sliding was 4.63 (range, 0-44.81) mm; and average angulation was varus $0.72^{\circ}$(range, $-7.6^{\circ}-12.7^{\circ}$). There were no cases of screw tip migration or nonunion, however, there were four cases of excessive screw sliding and six cases of varus angulation at more than $5^{\circ}$. Conclusion: CHS fixation in lateral decubitus position provides favorable clinical and radiological outcomes. This technique is advisable for regular CHS fixation of intertrochanteric fractures.

• Imaging Science in Dentistry
• /
• v.42 no.1
• /
• pp.47-54
• /
• 2012

Transmigration of an impacted tooth through the symphyseal suture is a rare and special developmental anomaly of unknown etiology that is unique to the mandibular canine. Maxillary canine transmigration is even rarer. Transmigrated canines are particularly significant due to the aesthetic and functional importance. A maxillary lateral incisor crossing the mid-palatal suture has never been reported in the literature. The aim of this report is to present the first case of simultaneous transmigration of a lateral incisor and canine in the maxilla. The paper also reports four unusual cases of unilateral canine transmigration in the maxilla and mandible and successful eruption of one of the transmigrated mandibular canines following orthodontic traction. Etiology of transmigration and its clinical considerations are also discussed.

• Journal of Soil and Groundwater Environment
• /
• v.23 no.1
• /
• pp.1-13
• /
• 2018

A series of experiments using transparent micromodels with an artificial pore network etched on glass plates was performed to investigate the effects of flow rate on the migration and distribution of resident wetting porewater (deionized water) and injecting non-wetting fluid (n-hexane). Multicolored images transformed from real RGB images were used to distinguish n-hexane from porewater and pore structure. Hexane flooding followed by immiscible displacement with porewater, migration through capillary fingering, preferential flow and bypassing were observed during injection experiments. The areal displacement efficiency increases as the injection of n-hexane continues until the equilibrium reaches. Experimental results showed that the areal displacement efficiency at equilibrium increases as the flow rate increases. Close observation reveals that preferential flowpaths through larger pore bodies and throats and clusters of entrapped porewater were frequently created at lower flow rate. At higher flow rate, randomly oriented forward and lateral flowpaths of n-hexane displaces more porewater at an efficiency close to stable displacement. It may resulted from that the pore pressure of n-hexane, at higher flow rate, increases fast enough to overcome capillary pressure acting on smaller pore throats as well larger ones. Experimental results in this study may provide fundamental information on migration and distribution of immiscible fluids in subsurface porous media.

• Journal of Korea Water Resources Association
• /
• v.56 no.12
• /
• pp.895-903
• /
• 2023

This study investigates the impact of riparian vegetation in the floodplain on channel stability, changes in bend curvature, and meandering channel migration. In channels with riparian vegetation, over time, meander width remains relatively constant, but selective bank erosion leads to meander development and downstream movement. During this process, bank erosion and changes in the riverbed are not significant, and the channel maintains relatively constant conditions with reduced sediment discharge and minimal variability. As the density of vegetation increases, bank erosion rates decrease. The erosion rates along the riverbanks increase with the density of vegetation on the floodplain, thus affecting the development of meanders. This factor notably contributes to enhancing riverbank stability and influencing channel changes through floodplain vegetation. Bank erosion rates and dimensionless bend curvature are greatest when there is no riparian vegetation but decrease in conditions with vegetation. Furthermore, the relationship between lateral migration rate and dimensionless bend curvature is similar to that of bank erosion rates. Therefore, riparian vegetation enhances channel stability, influencing bank erosion, meander curvature, and meander migration.

• Archives of Craniofacial Surgery
• /
• v.17 no.1
• /
• pp.20-24
• /
• 2016

Background: Midface concavity is a relatively common facial feature in East Asian populations. Paranasal augmentation is becoming an increasingly popular procedure for patients with mild concavity and normal occlusion. In this study, we evaluate clinical outcomes following a series of paranasal augmentation. Methods: A retrospective review was performed for patients with Class I occlusion who had undergone bilateral paranasal augmentation using custom-made silicone implants, between October 2005 and September 2013. Patient charts were reviewed for demographic information, concomitant operations, and postoperative complications. Preoperative and postoperative (1-month) photographs were used to evaluate operative outcome. Results: The review identified a total of 93 patients meeting study criteria. Overall, aesthetic outcomes were satisfactory. Five-millimeter thick silicone implant was used in 81 cases, and the mean augmentation was 4.26 mm for this thickness. Among the 93 patients, 2 patients required immediate implant removal due to discomfort. An additional 3 patients experienced implant migration without any extrusion. Nine patients complained of transient paresthesia, which had resolved by 2 weeks. There were no cases of hematoma or infection. All patients reported improvement in their lateral profile and were pleased at follow-up. Complications that arose postoperatively included 9 cases of numbness in the upper lip and 3 cases of implant migration. All cases yielded satisfactory results without persisting complications. Sensations were fully restored postoperatively after 1 to 2 weeks. Conclusion: Paranasal augmentation with custom-made silicone implants is a simple, safe, and inexpensive method that can readily improve the lateral profile of a patient with normal occlusion. When combined with other aesthetic procedures, paranasal augmentation can synergistically improve outcome and lead to greater patient satisfaction.

• Fisheries and Aquatic Sciences
• /
• v.15 no.2
• /
• pp.117-123
• /
• 2012

The starry flounder Platichthys stellatus, like all flatfish, exhibits conspicuous lateral asymmetry in numerous traits, most obvious of which is the migration of one eye to the other side of the head during metamorphosis. Additional changes related to eye migration include asymmetrical pigmentation, and a behavioral shift from larvae that exhibit upright, open-water swimming to juveniles and adults that lie on the ocean floor, eye side up. However, the morphology of these juveniles has been quite plastic in recent years, a phenomenon which is thought to be related to a diverse suite of semi-intensive and intensive larviculture methods. The cause of morphological abnormalities in the farmed flatfish is poorly understood. In the present study, we observe the features of morphological specificity and abnormality of immature fish (mean total length 23 cm) and survey the occurrence frequency of the specificity and abnormality of juvenile (mean total length 6.70 cm) in artificial culture facility. We find 2 types of abnormality (e.g., albino in ocular side and hypermelanosis in blind side) and 1 type of specificity (e.g., lateral polymorphism). These considerably differ from normal individuals (has sinistral eye and pigmented on only one side) by several characteristics (dextral eye, ocular side albinism, blind side hypermelanosis). The incidences of albinism, hypermelanosis, and body reversal are $10.1{\pm}2.56%$, $91.7{\pm}1.7%$, and $13.1{\pm}1.1%$, respectively. These suggest that these morphometric and morphological differences occur more in artificial environment during and just after metamorphosis.

• Nuclear Engineering and Technology
• /
• v.53 no.4
• /
• pp.1119-1126
• /
• 2021

Spacer grid with mixing vane had been widely used in nuclear reactor core. One of the main feather of spacer grid with mixing vane was that strong swirl flow was formed after the spacer grid. The swirl flow not only changed the bubble generation in the near wall field, but also affected the bubble behaviors in the center region of the subchannel. The interaction between bubble and the swirl flow was one of the basic phenomena for the two phase flow modeling in fuel assembly. To obatin better understanding on the bubble behaviors in swirl flow, full three dimension numerical simulations were conducted in the present paper. The swirl flow was assumed in the cylindral calculation domain. The bubble interface was captured by Volume Of Fluid (VOF) method. The properties of saturated water and steam at different pressure were applied in the simulation. The bubble trajectory, motion, shape and force were obtained based on the bubble parameters captured by VOF. The simulation cases in the present study included single bubble with different size, at different angular velocity conditions and at different pressure conditions. The results indicated that bubble migrated to the center in swirl flow with spiral motion type. The lateral migration was mainly related to shear stress magnitude and bubble size. The bubble moved toward the center with high velocity when the swirl magnitude was high. The largest bubble had the highest lateral migration velocity in the present study range. The effect of pressure was small when bubble size was the same. The prelimenery simulation result would be beneficial for better understanding complex two phase flow phenomena in fuel assembly with spacer grid.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.17 no.1
• /
• pp.163-171
• /
• 1987

The author has clinically and radiologically investigated 57 cases of odontogenic keratocyst in 47 patients consisted of 26 males and 21 females aged from.2 to 63 years, who were pathologically diagnosed as odontogenic keratocyst at infirmaries of dental colleges, Yonsei University and Seoul national university during 1965-1986. The results were as follows: 1. The peak incidence of the disease was on their teenagers (29.8%). The ratio of Male/Female was 1.23:1 and incidence rate of males showed higher than their counterpart. 2. The most frequent complaints were swelling in (65.9%) followed by pus discharge, unknown mass, pain, residual root. 3. The most common site was mandibular third molar and mandibular ramus region (15.8%) followed by mandibular body and ramus, mandibular third molar, mandibular anterior teeth. Incidence of this disease in mandible was higher than in maxilla. 4. The lesions not associated with adjacent teeth were (14.0%) and in the lesions associated with adjacent teeth (35.1%) showed root resorption, (50.9%) were without root resorption, (35.1%) showed tooth migration and (50.9%) were without tooth migration. 5. The border types of the lesions were scalloped type in (52.6%), smooth type in (47.4%) and morphological type were unilocular in (50.9%), multilocular in (49.1%). 6. The radiologic cyst type of the lesions were follicular type (42.1%) followed by primordial, unclassified odontogenic, residual, lateral periodontal, median mandibular, globulomaxillary type.