• Title/Summary/Keyword: Proximal

Search Result 2,552, Processing Time 0.031 seconds

Pterional or Subfrontal Access for Proximal Vascular Control in Anterior Interhemispheric Approach for Ruptured Pericallosal Artery Aneurysms at Risk of Premature Rupture

  • Park, Jaechan
    • Journal of Korean Neurosurgical Society
    • /
    • v.60 no.2
    • /
    • pp.250-256
    • /
    • 2017
  • Objective : Cases of a ruptured pericallosal artery aneurysm with a high risk of intraoperative premature rupture and technical difficulties for proximal vascular control require a technique for the early and safe establishment of proximal vascular control. Methods : A combined pterional or subfrontal approach exposes the bilateral A1 segments or the origin of the ipsilateral A2 segment of the anterior cerebral artery (ACA) for proximal vascular control. Proximal control far from the ruptured aneurysm facilitates tentative clipping of the rupture point of the aneurysm without a catastrophic premature rupture. The proximal control is then switched to the pericallosal artery just proximal to the aneurysm and its intermittent clipping facilitates complete aneurysm dissection and neck clipping. Results : Three such cases are reported : a ruptured pericallosal artery aneurysm with a contained leak of the contrast from the proximal side of the aneurysm, a low-lying ruptured pericallosal artery aneurysm with irregularities on its proximal wall, and a multilobulated ruptured pericallosal artery aneurysm with the parasagittal bridging veins hindering surgical access to the proximal parent artery. In each case, the proposed combined pterional-interhemispheric or subfrontal-interhemispheric approach was successfully performed to establish proximal vascular control far from the ruptured aneurysm and facilitated aneurysm clipping via the interhemispheric approach. Conclusion : When using an anterior interhemispheric approach for a ruptured pericallosal artery aneurysm with a high risk of premature rupture, a pterional or subfrontal approach can be combined to establish early proximal vascular control at the bilateral A1 segments or the origin of the A2 segment.

Is Adjacent Segment Disease More Frequent in Proximal Levels in Comparison with Distal Levels? Based on Radiological Data of at Least 2 Years Follow Up with More than 2 Level Thoracolumbar Fusions

  • Kim, Jung-Ho;Ryu, Dal-Sung;Yoon, Seung-Hwan
    • Journal of Korean Neurosurgical Society
    • /
    • v.62 no.5
    • /
    • pp.603-609
    • /
    • 2019
  • Objective : The purpose of this retrospective study was to determine which of the proximal adjacent segment disease (ASD) and distal ASD was more prevalent and what parameters is more related to ASD in proximal levels and distal levels after more than 2 levels fusions. Methods : The medical records were reviewed retrospectively for 856 cases. A total of 66 cases of ASD were enrolled. On preop magnetic resonance imaging, disc degeneration was measured at the upper and lower parts of surgically treated levels and confirmed by the commonly used Pfirrmann grade. Segmental flexibility in sagittal plane was embodied in segment range of motion (ROM) obtained through flexion and extension X-ray before surgery. Coronal angle was recorded as methods Cobb's angle including fusion levels preoperatively. For the comparison of categorical variables between two independent groups, the chi-square test and Fisher exact test were performed. Results : Proximal ASD and distal ASD were 37/856 (4.32%) and 29/856 (3.39%), respectively. The incidence of proximal ASD was relatively high but insignificant differences. In comparison between ASD group and non ASD group, proximal Pfirmman was higher in proximal ASD and distal Pfirmman was higher in distal ASD group (p=0.005, p<0.008, respectively). However, in the ROM, proximal ROM was higher in proximal ASD, but distal ROM was not different between the two groups (p<0.0001, p=0.995, respectively). Coronal angle was not quite different in both groups (p=0.846). Conclusion : In spite of higher frequency in ASD in proximal level in spinal fusion, it is not clear that incidence of ASD in proximal level is not higher than that of distal ASD group in more than 2 level thoracolumbar fusions. Not only Pfirrmann grade but also proximal segmental ROM is risk factor for predicting the occurrence of ASD in patients more than 2 level of thoracolumbar spine fusion operation excluding L5S1.

F-PROXIMAL FLOWS

  • Kim, Young-Key;Byun, Hee-Young
    • Communications of the Korean Mathematical Society
    • /
    • v.13 no.1
    • /
    • pp.131-136
    • /
    • 1998
  • The proximal flow have been introduced and studied by J. Auslander [1] and R. Ellis [2]. S. Glasner showed the various properties of the proximal flow in [7]. S. K. Kaul [3] have introduced the first prolongation set which contains the orbit closure. We define the F-proximal flow and $FP_\pi(y)$ by using the first prolongation set and investigated its properties.

  • PDF

PROXIMAL AND DISTAL HOMOMORPHISMS OF FLOWS

  • Song, Hyungsoo
    • Korean Journal of Mathematics
    • /
    • v.13 no.2
    • /
    • pp.235-239
    • /
    • 2005
  • In this paper we study some characterizations of proximal, distal and almost one to one homomorphisms of flows. In particular we show that if the almost one to one proximal extension of a minimal flow is weakly almost periodic, then it is minimal.

  • PDF

Digital contrast subtraction radiography for proximal caries diagnosis (인접면 치아우식 진단을 위한 디지털 방사선 조영 공제술)

  • Kang Byung-Cheol;Yoon Suk-Ja
    • Imaging Science in Dentistry
    • /
    • v.32 no.3
    • /
    • pp.123-127
    • /
    • 2002
  • Purpose : To determine whether subtraction images utilizing contrast media can improve the diagnostic performance of proximal caries diagnosis compared to conventional periapical radiographic images. Materials and Methods: Thirty-six teeth with 57 proximal surfaces were radiographied using a size #2 RVG-ui sensor (Trophy Radiology, Marne-la-Vallee, France). The teeth immersed in water-soluble contrast media and subtraction images were taken. Each tooth was then sectioned for histologic examination. The digital radiographic images and subtraction images were examined and interpreted by three dentists for proximal caries. The results of the proximal caries diagnosis were then verified with the results of the histologic examination. Results: The proximal caries sensitivity using digital subtraction radiography was significantly higher than simply examining a single digital radiograph. The sensitivity of the proximal dentinal carious lesion when analyzed with the subtraction radiograph and the radiograph together was higher than with the subtraction radiograph or the radiograph alone. Conclusion: The use of subtraction radiography with contrast media may be useful for detecting proximal dentinal carious lesions.

  • PDF

New Surgical Technique for Harvesting Proximal Fibular Epiphysis in Free Vascularized Epiphyseal Transplantation (혈관부착 근위비골성장판 이식시 공여부 수술의 새로운 술식)

  • Chung, Duke-Whan
    • Archives of Reconstructive Microsurgery
    • /
    • v.5 no.1
    • /
    • pp.106-111
    • /
    • 1996
  • Purpose : Propose a surgical technique in donor harvesting method in free vascularized proximal fibular epiphysis. Methodology : Concerned about growth potentials of the transplanted epiphysis in our long term results of the epiphyseal transplanted 13 cases more than 4 years follow-up, anterior tibial artery which contains anterior tibial recurrent artery is most reliable vessel to proximal fibular epiphysis which is the best donor of the free vascularized epiphyseal transplantation. In vascular anatomical aspect proximal fibular epiphysis norished by latearl inferior genicular artery from popliteal, posterior tibial recurrent artery and anterior tibial recurrent artery from anterior tibial artery and peroneal artery through metaphysis. The lateral inferior genicular artery is very small and difficult to isolate, peroneal artery from metaphysis through epiphyseal plate can not give enough blood supply to epiphysis itself. The anterior tibial artery which include anterior tibial recurrent and posterior tibial recurrent artery is the best choice in this procedure. But anterior tibial recurrent artery merge from within one inch from bifucating point of the anterior and posterior tibial arteries from popliteal artery. So it is very difficult to get enough vascular pedicle length to anastomose in recipient vessel without vein graft even harvested from bifucating point from popliteal artery. Authors took recipient artery from distal direction of anterior tibial artery after ligation of the proximal popliteal side vessel, which can get unlimited pedicle length and safer dissection of the harvesting proximal fibular epiphysis. Results : This harvesting procedure can performed supine position, direct anterolateral approach to proximal tibiofibular joint. Dissect and isolate the biceps muscle insertion from fibular head, micro-dissection is needed to identify the anterior tibial recurrent arteries to proximal epiphysis, soft tissue release down to distal and deeper plane to find main anterior tibial artery which overlying on interosseous membrane. Special care is needed to protect peroneal nerve damage which across the surgical field. Conclusions : Proximal fibular epiphyseal transplantation with distally directed anterior tibial artery harvesting technique is effective and easier dissect and versatile application with much longer arterial pedicle.

  • PDF

A Comparison of Bone Mineral Density in Osteoporotic Facture of the Proximal Femur Using Dual Energy X-ray Absorptiometry (대퇴 근위부 골절환자에서 이중에너지 방사선흡수계측법을 이용한 부위별 골밀도 비교)

  • Lee, Jong-Seok;Kim, Keung-Sik;Yoo, Beong-Gyu
    • Journal of radiological science and technology
    • /
    • v.23 no.2
    • /
    • pp.13-19
    • /
    • 2000
  • There were some controversies about direct cause of hip fracture. We attempted to look at 40 osteoporotic proximal femur fractures in women over 50 years between March in 1999 and Febuary in 2000. The bone density of the fracture group and the healthy 85 control group was measured by Dual Energy X-ray absorptiometry(DEXA). The result was compared using age matched paired T test. The results were as follows ; 1. The femoral neck fractures were 14 cases and the trochanteric fractures were 26 cases. Mean age at a fracture was 67.1 years in neck fracture group and 76.5 years in trochanteric fracture. 2. In the control group, the bone density of both side of the proximal femur was measured and it showed statistically no difference between both sides in same person. 3. The bone density of neck, Ward's triangle, trochanter(P<0.05) and lumbar spine(P<0.001) was significantly reduced in the proximal femoral fracture group comparing with the control group. 4. The bone density of neck, Ward's triangle, trochanter(P<0.05) was significantly reduced in the proximal femoral neck fracture group comparing with the control group, but there was no statistical difference in lumbar spine comparing with the control group. 5. The bone density of neck, Ward's triangle, trochanter and lumbar spine(P<0.001) was significantly reduced in the proximal femoral neck fracture group comparing with the control group. We concluded that the bone mineral densities(BMD) of proximal femur and lumbar spine had decreased in hip fractures but that the bone mineral density and T-score % of the proximal femur were statistically lower than that of the lumbar spine. We suggest that measuring the bone mineral density of the proximal femur may reflect the weakness of the proximal femur more precisely than measuring the bone mineral density of the lumbar spine.

  • PDF

Incidence and Mortality after Proximal Humerus Fractures Over 50 Years of Age in South Korea: National Claim Data from 2008 to 2012

  • Park, Chanmi;Jang, Sunmee;Lee, Areum;Kim, Ha Young;Lee, Yong Beom;Kim, Tae Young;Ha, Yong Chan
    • Journal of Bone Metabolism
    • /
    • v.22 no.1
    • /
    • pp.17-21
    • /
    • 2015
  • Background: There has been lack of epidemiology of proximal humerus fracture using nationwide database in Asia. The purpose of this study was to investigate the incidence of proximal humerus fracture and its mortality following proximal humerus fracture in Korean over 50 years of age. Methods: The Korean National Health Insurance data were evaluated to determine the incidence and mortality of proximal humerus fracture aged 50 years or older from 2008 through 2012. Results: Proximal humerus fracture increased by 40.5% over 5 year of study. The incidence of fracture increased from 104.7/100,000 in 2008 to 124.7/100,000 in 2012 in women and from 45.3/100,000 in 2008 to 52.0/100,000 in 2012 in men, respectively. One year mortality rate after proximal humerus fracture was 8.0% in 2008 and 7.0% in 2012. One year mortality rate were 10.8% for men and 7.0% for women in 2008 and 8.5% for men and 6.4% for women in 2012. Conclusions: Our study showed that the proximal humerus fracture in elderly was recently increasing and associated with high mortality in Korea. Considering proximal humerus fracture was associated with an increased risk of associated fractures and an increased mortality risk, public health strategy to prevent the proximal humerus fracture in elderly will be mandatory.

Effects of High Glucose on Na,K-ATPase and Na/glucose Cotransporter Activity in Primary Rabbit Kidney Proximal Tubule Cells

  • Han, Ho-Jae
    • The Korean Journal of Physiology
    • /
    • v.29 no.1
    • /
    • pp.69-80
    • /
    • 1995
  • Renal proximal tubular hypertrophy and hyperfunction are known to be early manifestations of experimental and human diabetes. As the hypertrophy and hyperfunction have been suggested to be central components in the progression to renal failure, an understanding of their underlying causes is potentially important for the development of therapy. A primary rabbit kidney proximal tubule cell culture system was utilized to evaluate the possibility that the renal proximal tubular hypertrophy and hyperfunction observed in vivo in diabetes mellitus, can be attributed to effects of elevated glucose levels on membrane transport systems. Primary cultures of rabbit proximal tubules, which achieved confluence at 10 days, exhibited brush-border characteristics typical of proximal tubular cells. Northern analysis indicated $2.2{\sim}2.3$ and 2.0 kb Na/glucose cotransporter RNA species appeared in fresh and cultured proximal tubule cells after confluence, repectively. The cultured cells showed reduced Na/glucose cotransporter activity compared to fresh proximal tubules. Primary cultured proximal tubule cells incubated in medium containing 20 mM glucose have reduced ${\alpha}-MG$ transport compared to cells grown in 5 mM glucose. In the proximal tubule cultures incubated in medium containing 5 mM or 20 mM glucose, phlorizin at 0.5 mM inhibited 0.5 mM ${\alpha}-MG$ uptake by 84.35% or 91.85%, respectively. The uptake of 0.5 mM ${\alpha}-MG$ was similarly inhibited by 0.1 mM ouabain (41.97% or 48.03% inhibition was observed, respectively). In addition, ${\alpha}-MG$ uptake was inhibited to a greater extent when $Na^{+}$ was omitted from the uptake buffer (81.86% or 86.73% inhibition was observed, respectively). In cell homogenates derived from the primary cells grown in 5 mM glucose medium, the specific activity of the Na/K-ATPase $(6.17{\pm}1.27\;{\mu}mole\;Pi/mg\;protein/hr)$ was 1.56 fold lower than the values in cell homogenates treated with 360 mg/dl D-glucose, 20 mM $(9.67{\pm}1.22\;{\mu}mole\;Pi/mg\;protein/hr)$. Total $Rb^{+}$ uptake occurred at a significantly higher rate (1.60 fold increase) in primary cultured rabbit kidney proximal tubule cell monolayers incubated in 20 mM glucose medium $(10.48{\pm}2.45\;nM/mg\;protein/min)$ as compared with parallel cultures in 5 mM glucose medium. $Rb^{+}$ uptake rate in 5 mM glucose medium was reduced by 28% when the cultures were incubated with 1 mM ouabain. The increase of the $Rb^{+}$ uptake by rabbit kidney proximal tubule cells in 20 mM glucose could be attributed primarily to an increase in the rate of ouabain-sensitive $Rb^{+}$ uptake $(5\;mM\;to\;20\;mM;\;4.68{\pm}0.85\;to\;8.38{\pm}1.37\;nM/mg\;protein/min)$. In conclusion, the activity of the renal proximal tubular Na,K-ATPase is elevated in high glucose concentration. In contrast, the activity of the Nafglucose cotransport system is inhibited.

  • PDF

Detecting of Proximal Caries in Primary Molars using Pen-type QLF Device (펜-타입 QLF 장비의 임상적 유구치 인접면 우식 탐지 성능)

  • Cho, Hyejin;Kim, Hyuntae;Song, Ji-Soo;Shin, Teo Jeon;Kim, Jung-Wook;Jang, Ki-Taeg;Kim, Young-Jae
    • Journal of the korean academy of Pediatric Dentistry
    • /
    • v.48 no.4
    • /
    • pp.405-413
    • /
    • 2021
  • The purpose of this in vivo study was to assess the clinical screening performance of a quantitative light-induced fluorescence (QLF) device in detecting proximal caries in primary molars. Fluorescence loss, red autofluorescence and a simplified QLF score for proximal caries (QS-proximal) were evaluated for their validity in detecting proximal caries in primary molars compared to bitewing radiography. Three hundred and forty-four primary molar surfaces were included in the study. Carious lesions were scored according to lesion severity assessed by visual-tactile and radiographic examinations. The QLF images were analyzed for two quantitative parameters, fluorescence loss and red autofluorescence, as well as for QS-proximal. For both quantitative parameters and QS-proximal, the sensitivity, specificity and area under receiver operating curve (AUROC) were calculated as a function of the radiographic scoring index at enamel and dentin caries levels. Both quantitative parameters showed fair AUROC values for detecting dentine level caries (△F = 0.794, △R = 0.750). QS-proximal showed higher AUROC values (0.757 - 0.769) than that of visual-tactile scores (0.653) in detecting dentine level caries. The QLF device showed fair screening performance in detecting proximal caries in primary molars compared to bitewing radiography.