• Title/Summary/Keyword: Vertebral

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The Usefulness of Diffusion-weighted MR Imaging for Differentiation between Degenerative Spines and Infectious Spondylitis (퇴행성 척추와 감염성 척추염의 감별에 있어서 확산강조영상의 유용성)

  • 박원규;변우목;최준혁
    • Investigative Magnetic Resonance Imaging
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    • v.6 no.2
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    • pp.152-157
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    • 2002
  • Purpose : The differential diagnosis between Modic type I degenerative spine and infectious spondylitis sometimes is difficult, because the affected bone marrows in both disease show similar signal intensity on conventional MR imaging. We evaluate the usefulness of diffusion-wighted MR imaging for differential diagnosis between Modic type I degenerative spine and infectious spondylitis. Materials and methods : The spin-echo and diffusion-weighted MR images of eight patients with Modic type I degenerative spines and 14 patients with infectious spondylitis diagnosed by clinical findings or CT-guided biopsies we re analyzed. The diffusion-weighted imaging sequence was based on reversed fast imaging with steady-state precession (PSIF). Signal intensity changes of the vertebral bone marrow on conventional spin-echo and diffusion-weighted MR imaging were compared between degenerative spine and infectious spondylitis. Results : On T1-weighte d images, the affeted bone marrow in both disease showed hypointense signals. On T 2-weighted images, all of type I degenerative spine and 11 of infectious spondylitis showed hyperintensity, and three of infectious spondylitis showed heterogeneo us mixed signal intensity. On diffusion-weighted MR images, all of type I degenerative spine were hypointense with peripheral high signal intensity to normal vertebral body, but infectious spondylitis was hyperintense (n = 11) and hypointense (n=3). Conclusion : Diffusion-weighted MR imaging is useful to differentiate Modic type I degenerative spine from infectious spondylitis. On diffusion-weighted images, the high singal intensity of bone marrow suggests infectious spondylitis, whereas the low signal intensity of bone marrow with peripheral focal high signal intensity suggests type I degenerative spine.

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The Study of patient rotation angle to get the scapular true lateral image in scapular lateral projection (견갑골 측방향 촬영에서 견갑골 정측면상을 얻기 위한 환자의 회전각도에 관한 연구)

  • Park, Ki-Bong;Kang, In-Hyi;Choi, Nam-Kil;Jang, Young-Il;Jeon, Ju-Seob
    • Journal of radiological science and technology
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    • v.28 no.3
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    • pp.203-209
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    • 2005
  • Objective True lateral scapular image was very important to diagnosis the scapular fracture and dislocation induced by traumatic injury. The aim of this study was to know the patient rotation angle to be showing the scapular true lateral in Korean. Subjects and Materials Thirty patients(22men, 8 women, mean ages 53.4)with scapular pain, had supine anteroposterior projection taken with $32^{\circ}$, $37^{\circ}$, $42^{\circ}$ trunk rotation angle changing the manual angulation material. Radiographs were evaluated independently by 5 experienced observers(1 orthopedics surgery specialist, 1 diagnostic radiology specialist, 3 radiological technologist) They assessed overlab of vertebral border and axillary border of scapular as follows; Totally overlapping of vertebral border and axillary border is 4, partially overlapping is 3, not overlapping is 2 and oblique location with two borders is 1. All observers scored using by PACS monitor. Results $32^{\circ}$ trunk rotation was scored $1.53{\pm}0.39$, $37^{\circ}$ trunk rotation was scored $3.83{\pm}0.15$ and $42^{\circ}$trunk rotation was scored $2.17{\pm}0.43$. There was no difference(p<0.05) between group of more than 100cm of the girth of the chest and group of less than 100cm. Similarly, men and women group showed no difference(p<0.05) with trunk rotation statistically. Conclusions There was no result of trunk rotation angle to radiograph the true scapular lateral image up to date. This studies were summarized as follows; Adaptation of $37^{\circ}$ trunk rotation was the best to show the true scapular lateral image in Korean. Our results were very useful to get the true scapular lateral images in clinic.

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Comparisons of Unicortical and Bicortical Lateral Mass Screws in the Cervical Spine : Safety vs Strength (경추부의 후관절 나사못 고정술에서 단피질삽입법과 양피질 삽입법 간의 특성에 관한 비교)

  • Park, Choon-Keun;Hwang, Jang-Hoe;Ji, Chul;Lee, Jae Un;Sung, Jae Hoon;Choi, Seung-Jin;Lee, Sang-Won;Seybold, Eric;Park, Sung-Chan;Cho, Kyung-Suok;Park, Chun-Kun;Kang, Joon-Ki
    • Journal of Korean Neurosurgical Society
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    • v.30 no.10
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    • pp.1210-1219
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    • 2001
  • Introduction : The purpose of this study was to analyze the safety, pullout strength and radiographic characteristics of unicortical and bicortical screws of cervical facet within cadaveric specimens and evaluate the influence of level of training on the positioning of these screws. Methods : Twenty-one cadavers, mean 78.9 years of age, underwent bilateral placement of 3.5mm AO lateral mass screw from C3-C6(n=168) using a slight variation of the Magerl technique. Intraoperative imaging was not used. The right side(unicortical) utilized only 14mm screws(effective length of 11mm) while on the left side to determine the length of the screw after the ventral cortex had been drilled. Three spine surgeons(attending, fellow, chief resident) with varying levels of spine training performed the procedure on seven cadavers each. All spines were harvested and lateral radiographs were taken. Individual cervical vertebrae were carefully dissected and then axial radiographs were taken. The screws were evaluated clinically and radiographically for their safety. Screws were graded clinically for their safety with respect to the spinal cord, facet joint, nerve root and vertebral artery. The grades consisted of the following categories : "satisfactory", "at risk" and "direct injury". Each screw was also graded according to its zone placement. Screw position was quantified by measuring a sagittal angle from the lateral radiograph and an axial angle from the axial radiograph. Pull-out force was determined for all screws using a material testing machine. Results : Dissection revealed that fifteen screws on the left side actually had only unicortical and not bicortical purchase as intended. The majority of screws(92.8%) were satisfactory in terms of safety. There were no injuries to the spinal cord. On the right side(unicortical), 98.9% of the screws were "satisfactory" and on the left side(bicortical) 68.1% were "satisfactory". There was a 5.8% incidence of direct arterial injury and a 17.4% incidence of direct nerve root injury with the bicortical screws. There were no "direct injuries" with the unicortical screws for the nerve root or vertebral artery. The unicortical screws had a 21.4% incidence of direct injury of the facet joint, while the bicortical screws had a 21.7% incidence. The majority of "direct injury" of bicortical screws were placed by the surgeon with the least experience. The performance of the resident surgeon was significantly different from the attending or fellow(p<0.05) in terms of safety of the nerve root and vertebral artery. The attending's performance was significantly better than the resident or fellow(p<0.05) in terms of safety of the facet joint. There was no relationship between the safety of a screw and its zone placement. The axial deviation angle measured $23.5{\pm}6.6$ degrees and $19.8{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The resident surgeon had a significantly lower angle than the attending or fellow(p<0.05). The sagittal angle measured $66.3{\pm}7.0$ degrees and $62.3{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The attending had a significantly lower sagittal angle than the fellow or resident(p<0.05). Thirty-three screws that entered the facet joint were tested for pull-out strength but excluded from the data because they were not lateral mass screws per-se and had deviated substantially from the intended final trajectory. The mean pull-out force for all screws was $542.9{\pm}296.6N$. There was no statistically significant difference between the pull-out force for unicortical($519.9{\pm}286.9N$) and bicortical($565.2{\pm}306N$) screws. There was no significant difference in pull-out strengths with respect to zone placement. Conclusion : It is our belief that the risk associated with bicortical purchase mandates formal spine training if it is to be done safely and accurately. Unicortical screws are safer regardless of level of training. It is apparent that 14mm lateral mass screws placed in a supero-lateral trajectory in the adult cervical spine provide an equivalent strength with a much lower risk of injury than the longer bicortical screws placed in a similar orientation.

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Usefulness Evaluation of Artifacts by Bone Cement of Percutaneous Vertebroplasty Performed Patients and CT Correction Method in Spine SPECT/CT Examinations (척추 뼈 SPECT/CT검사에서 경피적 척추성형술 시행 환자의 골 시멘트로 인한 인공물과 CT보정방법의 유용성 평가)

  • Kim, Ji-Hyeon;Park, Hoon-Hee;Lee, Juyoung;Nam-Kung, Sik;Son, Hyeon-Soo;Park, Sang-Ryoon
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.49-61
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    • 2014
  • Purpose: With the aging of the population, the attack rate of osteoporotic vertebral compression fracture is in the increasing trend, and percutaneous vertebroplasty (PVP) is the most commonly performed standardized treatment. Although there is a research report of the excellence of usefulness of the SPECT/CT examination in terns of the exact diagnosis before and after the procedure, the bone cement material used in the procedure influences the image quality by forming an artifact in the CT image. Therefore, the objective of the research lies on evaluating the effect the bone cement gives to a SPECT/CT image. Materials and Methods: The images were acquired by inserting a model cement to each cylinder, after setting the background (3.6 kBq/mL), hot cylinder (29.6 kBq/mL) and cold cylinder (water) to the NEMA-1994 phantom. It was reconstructed with Astonish (Iterative: 4 Subset: 16), and non attenuation correction (NAC), attenuation correction (AC+SC-) and attenuation and scatter correction (AC+SC+) were used for the CT correction method. The mean count by each correction method and the count change ratio by the existence of the cement material were compared and the contrast recovery coefficient (CRC) was obtained. Additionally, the bone/soft tissue ratio (B/S ratio) was obtained after measuring the mean count of the 4 places including the soft tissue(spine erector muscle) after dividing the vertebral body into fracture region, normal region and cement by selecting the 20 patients those have performed PVP from the 107 patients diagnosed of compression fracture. Results: The mean count by the existence of a cement material showed the rate of increase of 12.4%, 6.5%, 1.5% at the hot cylinder of the phantom by NAC, AC+SC- and AC+SC+ when cement existed, 75.2%, 85.4%, 102.9% at the cold cylinder, 13.6%, 18.2%, 9.1% at the background, 33.1%, 41.4%, 63.5% at the fracture region of the clinical image, 53.1%, 61.6%, 67.7% at the normal region and 10.0%, 4.7%, 3.6% at the soft tissue. Meanwhile, a relative count reduction could be verified at the cement adjacent part at the inside of the cylinder, and the phantom image on the lesion and the count increase ratio of the clinical image showed a contrary phase. CRC implying the contrast ratio and B/S ratio was improved in the order of NAC, AC+SC-, AC+SC+, and was constant without a big change in the cold cylinder of the phantom. AC+SC- for the quantitative count, and AC+SC+ for the contrast ratio was analyzed to be the highest. Conclusion: It is considered to be useful in a clinical diagnosis if the application of AC+SC+ that improves the contrast ratio is combined, as it increases the noise count of the soft tissue and the scatter region as well along with the effect of the bone cement in contrast to the fact that the use of AC+SC- in the spine SPECT/CT examination of a PVP performed patient drastically increases the image count and enables a high density of image of the lesion(fracture).

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A Clinical Evaluation of Splanchnic Nerve Block (내장신경차단에 관한 임상적 연구)

  • Kim, Soo-Yeoun;Oh, Hung-Kun;Yoon, Duek-Mi;Shin, Yang-Sik;Lee, Youn-Woo;Kim, Jong-Rae
    • The Korean Journal of Pain
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    • v.1 no.1
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    • pp.34-46
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    • 1988
  • Intractable pain from advanced carcinoma of the upper abdomen is difficult to manage. One method used to control pain associated with these malignancies is to block off the splanchnic nerve. In 1919 Kappis described a technique by which the splanchnic nerve of the upper abdomen could be anesthetized, using a percutaneous injection. This method has been used for the relief of upper abdominal pain due to hematoma and cancer of the pancreas, stomach, gall bladder, bile duct, and colon. During the Period from November 1968 to January 1986, this method was used in 208 cases of malignancy at Severance Hospital and clinically evaluated. Patients were retroactively grouped according to the stage of development of technique used. Twelve patients who received the treatment in the period from November 1968 to March 1977 were designate4i as group 1, 26 patients from April 1977 to April 1979 as group 2, and 170 from May 1979 to January 1986 as group 3. The results are as follows: 1) The number of patients receiving splanchnic nerve block has been increasing since 1977. 2) A total of 208 patients, including 133 males and 75 females, ranging in age from 18 to 84 and averaging 51. 3) The causes of pain were stomach cancer 90, pancreatic cancer 69, and miscellaneous cancer 49 cases respectively. 4) There were 57.7% who had surgery. and 3.7% of whom had chemotherapy before the splanchnic nerve block was done. 5) These blocks were carried out with the patient in the prone position as described by Dr. Moore. For group 2 and 3, C-arm image intensifier was used. In group 1, a 22 gauze loom long needle was inserted at the lower border of the 12th rib on each aide about 7\;cm from the midline. The average distance from the midline was $6.60{\pm}0.61\;cm$ on the left side and $6.60{\pm}0.83\;cm$ on the right side in group 2, and $5.46{\pm}0.76\;cm$ on the left side and $5.49{\pm}0.69\;cm$ on the right side in group 3. The average depth to which the needle was inserted was $8.60{\pm}0.52\;cm$ on the left side and $8.74{\pm}0.60\;cm$ on the right side in group 2, and $8.96{\pm}0.63\;cm$ on the left side and $9.18{\pm}0.57\;cm$ on the right side in group 3. 6) The points of the inserted needles were positioned in the upper quarter anteriorly, 51.8% on the left side and 54.4% n the right side of the L1 vertebra by lateral roentgenogram in group 3. The inserted needle points were located in the upper and anterolateral part, of the L1 vertebra 68.5% on the left side and 60.6won the right side, on the anteroposterior rentgenogram in group 3. The needle tip was not advanced beyond the anterior margin of the vertebral body. 7) In some case of group 3, contrast media was injected before the block was done. It shows, the spread upward along the anterior mal gin of the vertebral body. 8) The concentration and the average amount of drug used in each group was as follows: In group 1, $39.17{\pm}6.69\;ml$ of 0.5% -l% lidocaine or 0.25% bupivacaine were injected for the test block and one to three days after the test block $40.00{\pm}4.26\;ml$ of 50% alcohol was injected for the semipermanent block. In group 2, $13.75{\pm}4.88\;ml$ of 1% lidocaine were used as the test block and followed by $46.17{\pm}4.37\;ml$ of 50% alcohol was injected as the semipermanent block. In group 3, $15.63{\pm}1.19\;ml$ of 1% lidocaine for test block followed by $15.62{\pm}1.20\;ml$ of pure alcohol and $16.05{\pm}2.58\;ml$ of 50% alcohol for semipermanent block were injected. 9) The result of the test block was satisfactory in all cases. However the semipermanent block was 83.3 percent of the patients in group 1 who received relief from pain for at least 2 weeks after the block, 73.1% in group 2, and 91.8% in group 3. In these unsuccessful cases, 2 cases in group 1 were controlled by narcotics but 7 cases in group 2 and 14 cases in group 3 received the same splanchnic nerve block 1 or 2 times again within 2 weeks. But, in some cases it was 3 to i months before the 2nd block and in 1 cases even 7 years. 10) The most common complications of splanchnic nerve block were hypotensino(25.5%) occasional flushing of the face, nausea, vomiting, and chest discomfort. 11) For the patients in group 3, the supplemental block most commonly used was a continuous epidural block; it was used as a diagnostic block and to afford relief from pain before the splanchnic nerve block was done. 12) The interval between the receiving of the alcohol block and discharge was from 5 to 8 days in 61 cases(31.1%) and from 1 to 2 days in 48 cases(24.5%). From the above results, it can be concluded that the splanchnic nerve block done in the prone position with pure and 50% alcohol immediately after an effective test block with 1% lidocaine under C-arm fluoroscopic control is satisfactory and reliable. How to minimize the repeat block is still a problem to be solved.

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Osteological Development of Korean Striped Bitterling, Acheilognathus yamatsutae (Cyprinidae) (줄납자루, Acheilognathus yamatsutae (잉어과)의 골격 발달)

  • Song, Ho-Bok;Son, Yeong-Mok
    • Korean Journal of Ichthyology
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    • v.17 no.1
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    • pp.19-28
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    • 2005
  • Osteolgical development of Korean striped bitterling, Acheilognathus yamatsutae (Cyprinidae), were investigated using cartilage and bone staining. The parasphenoid, dentary, pterygoid, ceratohyal, branchial arch and parts of the caudal skeleton were formed first as cartilaginous elements at $6.82{\pm}0.08mm$ total length (TL). Formation of frontal, parietal, and maxillary were notable at $7.76{\pm}0.09mm$ TL, and the proximal radial, scapula,and coracoid in the pectoral girdle were developed at this stage. At the same time, the neural and hemal spine were present in the caudal vertebra. The opercle and branchiostegals were observed at $9.68{\pm}0,14mm$, and the posttemporal was formed at $12.9{\pm}40.64mm$ TL, respectively. Ossification in the parasphenoid, pharyngeal bone, dentary, premaxillary, maxillary, and opercle began at about $9.68{\pm}0.14mm$ TL. The cleithrum, supracleithrum, urostyle, and caudal fin were calcified at this stage. The vertebral column was formed and ossified at $11.52{\pm}0.13mm$ TL, and the frontal, preopercle, subopercle, and hyomandibular were ossified at $15.30{\pm}0.68mm$ TL. This fish was late in developing the skeletal formation and ossification as compared with other fishes.

Volumetric Estimation of the Prostate Gland using Computed Tomography in Normal Beagle Dogs (정상 비글견에서 컴퓨터단층촬영술을 이용한 전립선의 부피 평가)

  • Choi, Ji-Young;Choi, Soo-Young;Lee, Ki-Ja;Jeong, Woo-Chang;Han, Woo-Sok;Choi, Ho-Jung;Lee, Young-Won
    • Journal of Veterinary Clinics
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    • v.31 no.3
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    • pp.175-179
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    • 2014
  • The purpose of this study was to determine and compare prostate size using ultrasound and computed tomography (CT). The prostate gland was evaluated in eight normal Beagle dogs. Length, depth, and width of the prostate gland were measured by ultrasound and volume of the prostate was obtained from the two ellipsoid formula (US1, US2). Height, length, width, area, and volume of the prostate gland were measured by CT. Ratios of prostatic height, length, and width to the sixth lumbar vertebral body length were calculated. There was no significant difference between the US1 and US2 method, and between US2 and CT method, respectively. The prostatic volume calculated by US1 method was significantly lower than those with CT (p=0.029). The Upper limits of ratios of prostate length, height, and width to the length of the sixth lumbar vertebra were 1.3, 1.1, and 1.7, respectively. Among these prostate dimensions, prostate length and height could be a useful index in estimating prostate size regardless of body weight.

Anatomical Studies on the Skeleton of Thoracic Limb of Korean Native Goat (한국재래산양의 전지골격에 관한 해부학적 연구)

  • Kim, Jin-sang;Lee, Heung-shik S.;Lee, In-se
    • Korean Journal of Veterinary Research
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    • v.27 no.2
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    • pp.167-183
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    • 1987
  • The anatomical structure of the Skeleton of thoracic limb of thirty-one adult Korean native goats(body weight: 14~17kg) was observed after skeletal preparation, and the osteometry was performed in each bone. The results were as follows; 1. The thoracic limb of the Korean native goat was composed of scapula, humerus, radius, ulna, carpal bones, metacarpal bones, phalanges and sesamoid bones. 2. The scapula was flat and triangular in shape. There were no distinct tuber of spine and acromion in the spine. The subscapular fossa was deep and triangular in shape and the vertebral border was sigmoid form. The coracoid bone was formed as the coracoid process at the medial aspect of the supraglenoid tubercle but the clavicle wa.s not observed. The left and right scapular indexes were 57.92 and 58.31 and the glenoid cavity indexes were 89.23 and 86.82, respectively. 3. The greater tubercle of the humerus was devided into cranial and caudal parts. The third tubercle was observed and the face for the infraspinatus muscle was rectangular form. The left and right humerus indexes were 32.44 and 32.63, the head indexes were 94.13, 96.62 and the trochlear-epidondyle indexes were 67.32 and 65.81, respectively. 4. The radius and ulna were fused entirely except at the broad proximal and narrow distal interosseous spaces. The ulna was longer than the radius, and its reduced body and distal end were fused at the caudomedial surface of the radius. 5. The carpal bones were six in number. There were radial, intermediate, ulnar, accessory, second-third and fourth carpal hones in carpal bones. 6. The metacarpal bone was composed of a large metacarpal bone resulted from the fusion of the third and fourth metacarpal bones, and there was a metacarpal tubercle at the dorsolateral part of the proximal end. There were no vestiges of the second and fifth metacarpal bones. 7. The digits were composed of third and fourth digits and each digit was composed of the proximal, middle and distal phalanges. 8. The sesamoid bones were six in number. There were two at the fetlock joint and one at the coffine joint palmarly in each digit. 9. The ratios of the lengths among the scapula, humerus, antebrachium and metacarpal bone were 1.42 : 1.47 : 1.77 : 1.00 in the left and 1.42 : 1.45 : 1.77 : 1.00 in the right, respectively.

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Clinical Evaluation of Surgical Treatments for Ten Cases of Tuberculous Spondylitis (결핵성 척추염 10례의 수술적 치료에 관한 임상적 고찰)

  • Whee, Sung Mock;Eoh, Whan;Nam, Do Hyun;Lee, Jung Il;Kim, Jong Soo;Hong, Seung-Chyul;Shin, Hyung Jin;Park, Kwan;Kim, Jong-Hyun
    • Journal of Korean Neurosurgical Society
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    • v.30 no.11
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    • pp.1314-1319
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    • 2001
  • Objects : Because of the nonspecific nature of symptoms in tuberculous spondylitis, a delay in the diagnosis can result in progressive neurologic deficits. The authors evaluate the clinical and the radiological results of the 10 cases of surgically treated tuberculous spondylitis. Clinical materials & Methods : We retrospectively analyzed the medical records of 10 patients with tuberculous spondylitis who were treated between February 1996 and March 2000. Six patients were female, and four were male. Mean age was 43 years old, and mean follow-up period was 20.5 months. All patients were treated with 12 months of antituberculous medication postoperatively, and were followed by complete blood count, ESR, spine X-ray and MRI. Results : The lumbar spine was involved in 5 patients, the thoracic in 4, and the thoracolumbar in one. The infected vertebral bodies were 2.8 in average. The associated lesions were pulmonary tuberculosis in 3 cases, and renal tuberculosis in one. Five patients were treated by anterior debridement and fusion with bone graft using anterior instrumentation, 2 with anterior debridement and fusion with bone graft(Hong Kong procedure only), 1 with Hong Kong procedure with posterior spinal instrumentation, and 2 were managed with posterior debridement and posterior spinal instrumentation. All patients improved after operation, and the average kyphotic angle decreased postoperatively. Postoperatively, one patient had a fistula at the operative site. Conclusion : The debridement and minimal level fusion of motion segment with instrument fixation is one of surgical option for tuberculous spondyltis to preserve the spine motion segment as much as possible. Spine instability and kyphosis were prevented by anterior and posterior spinal instrumentation. But, large number of cases and longer period follow-up study in future will be needed to confirm the long term results.

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Ostelogical Development of Larvae and Juveniles of Hyporhampus sajori (Teleostei: Hemiramphidae) (학공치, Hyporhampus sajori (Temminck et Schlegel) 자치어(仔稚魚)의 골격 발달)

  • Lee, Seung-Ju;Kim, Yong-Uk;Han, Kyeong-Ho
    • Korean Journal of Ichthyology
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    • v.13 no.3
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    • pp.173-180
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    • 2001
  • The fertilized eggs of Hyporhampus sajori (Temminck et Schlegel) were collected on the shore of Youngil Bay, Phohang-shi, Korea, on May 27, 1991, and were hatched and reared in the laboratory to investigate osteological development of larvae and juveniles. The newly hatched larvae were 7.00~8.50 mm (mean 7.80 mm, n = 5) in total length (TL) and had an ossified cranium, visceral skeleton and shoulder girdle bones. At 8 days, the larvae had attained 10.07~14.75 mm (mean 13.07 mm, n = 5) in TL had elongated dentaries anteriorly, and their vertebral columns were posteriory ossified. At 14 days, the larvae had attained 17.62~19.35 mm (mean 19.20 mm, n = 5) in TL, had ossified pterygiophores, and 41 slender ribs on the vertbrae. At 16 days, the larvae were 18.90~24.72 mm (mean 23.00 mm, n = 5) in TL and had three ossified epurals. Ossification of the jaw bone and operculum of the newly hatched larvae, which was related to feeding and respiration was almost completed 37 days after hatching.

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