• Title/Summary/Keyword: Magnetic resonance images

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In Vivo Three-Dimensional Evaluation of the Functional Length of Glenohumeral Ligaments

  • Yang, Chen;Goto, Akira;Sahara, Wataru;Koishi, Hayato;Yoshikawa, Hideki;Sugamoto, Kazuomi
    • The Academic Congress of Korean Shoulder and Elbow Society
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    • 2009.03a
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    • pp.43-43
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    • 2009
  • Glenohumeral ligaments play an important role in stabilizing the shoulder. However, it is impossible to know how they function in vivo during shoulder motion. To help elucidate this stabilizing role, we conducted in vivo three-dimensional kinematics of the normal shoulder joint using a markerless bone-registration technique. Magnetic resonance images of 14 shoulder joints of 7 healthy volunteers were acquired for 7 isometric abduction positions between $0^{\circ}$ and $180^{\circ}$. We then calculated three-dimensional shortest paths between the origin and insertion of each ligament based on anatomical study in each abduction position. At $0^{\circ}$ of abduction, the posterior band of the coracohumeral ligament displayed the maximum length. At $30^{\circ}$ of abduction, the superior glenohumeral ligament displayed the maximum length. At $60^{\circ}$ of abduction, the anterior band of the coracohumeral ligament and the middle glenohumeral ligament displayed the maximum length. At $120^{\circ}$ of abduction, the anterior band of the inferior glenohumeral ligament displayed the maximum length. We think that the maximum length of these results is an important influence on the function of the soft tissue stabilizer.

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Management of Cerebrospinal Fluid Leak after Traumatic Cervical Spinal Cord Injury (경추 손상 후 뇌척수액 유출에 대한 관리)

  • Lee, Soo Eon;Chung, Chun Kee;Jahng, Tae-Ahn;Kim, Chi Heon
    • Journal of Trauma and Injury
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    • v.26 no.3
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    • pp.151-156
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    • 2013
  • Purpose: Traumatic cervical SCI is frequently accompanied by dural tear and the resulting cerebrospinal fluid (CSF) leak after surgery can be troublesome and delay rehabilitation with increasing morbidity. This study evaluated the incidence of intraoperative CSF leaks in patients with traumatic cervical spinal cord injury (SCI) who underwent anterior cervical surgery and described the reliable management of CSF leaks during the perioperative period. Methods: A retrospective study of medical records and radiological images was done on patients with CSF leaks after cervical spine trauma. Results: Seven patients(13.2%) were identified with CSF leaks during the intraoperative period. All patients were severely injured and showed structural abnormalities on the initial magnetic resonance image (MRI) of the cervical spine. Intraoperatively, no primary repair of dural tear was attempted because of a wide, rough defect size. Therefore, fibrin glue was applied to the operated site in all cases. Although a wound drainage was inserted, it was stopped within the first 24 hours after the operation. No lumbar drainage was performed. Postoperatively, the patients should kept their heads in an elevated position and early ambulation and rehabilitation were encouraged. None of the patients developed complications related to CSF leaks during admission. Conclusion: The incidence of CSF leaks after surgery for cervical spinal trauma is relatively higher than that of cervical spinal stenosis. Therefore, one should expect the possibility of a dural tear and have a simple and effective management protocol for CSF leaks in trauma cases established.

Accuracy of Ventricular Volume and Ejection Fraction Measured by Gated Tl-201 Perfusion Single Photon Emission Tomography (심전도 게이트 심근관류 Tl-201 SPECT로 측정된 좌심실 기능 및 좌심실 용적의 정확성)

  • Pai, Moon-Sun;Moon, Dae-Hyuk
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.2
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    • pp.94-99
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    • 2005
  • Electrocardiogram-gated single photon omission computed tomography (SPECT) provides valuable information in the assessment of both myocardial perfusion and ventricular function. Tl-201 is a suboptimal isotope for gating. Tl-201 images are more blurred compared with Tc-99m tracers due to the increased amount of scattered photons and use of a smooth filter. The average myocardial count densities are approximately one-half those of conventional technetium tracers. However, Tl-201 is still widely used because of its well-established utility for assessing myocardial perfusion, viability and risk stratification. Gated SPECT with Tl-201 enables us to assess both post-stress and rest left ventricular volume and function. Previous studies with gated Tl-201 SPECT measurements of ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV) have shown high correlation with first-pass radionuclide angiography, gated blood pool scan, Tc-99m-MIBI gated SPECT, contrast ventriculography, echocardiography, and 3-dimensional magnetic resonance imaging. However, problems related to these studies include few agreement data of EDV and ESV, use of a reference method that is likely to have the same systemic errors (gated Tc-99m-MIBI SPECT), and other technical factors related to the count density of gated SPECT. With optimization of gated imaging protocols and more validation studies, gated Tl-201 SPECT would be an accurate method to provide perfusion and function information in patients with coronary artery disease.

Living Related Liver Transplantation in an Infant with Neonatal Hemochromatosis

  • Choi, Shin Jie;Choi, Jong Sub;Chun, Peter;Yoo, Jung Kyung;Moon, Jin Soo;Ko, Jae Sung;Kim, Woo Sun;Kang, Gyeong Hoon;Yi, Nam-Joon
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.19 no.2
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    • pp.147-151
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    • 2016
  • Neonatal hemochromatosis (NH) is a severe neonatal liver injury that is confirmed by extra-hepatic iron accumulation. Although a recent study described treating NH with exchange transfusions and intravenous immunoglobulin, liver transplantation should be considered for patients with severe liver failure that does not respond to other medical treatment. Herein, we report the case of a two-month-old female infant who presented with persistent ascites and hyperbilirubinemia. Her laboratory findings demonstrated severe coagulopathy, high indirect and direct bilirubin levels, and high ferritin levels. Abdominal magnetic resonance imaging presented low signal intensity in the liver on T2-weighted images, suggesting iron deposition. The infant was diagnosed with NH as a result of the clinical findings and after congenital infection and metabolic diseases were excluded. The infant was successfully treated with a living-donor liver transplantation. Living related liver transplantation should be considered as a treatment option for NH in infants.

Discal Cyst in a Malamute Dog (말라뮤트 개에서 발생한 디스크 낭종 증례)

  • Kim, Jae-Hwan;Park, Noh-Won;Kwon, Young-Hang;Lim, Jong-Hwan;Bae, Jang-Hoon;Eom, Ki-Dong
    • Journal of Veterinary Clinics
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    • v.31 no.5
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    • pp.445-448
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    • 2014
  • A 7-year-old, male Alaskan malamute was referred for a routine dental management. On the physical examination, the right hindlimb ataxia with a mild delay in proprioception was noted. On magnetic resonance images, an extradural ventral cystic structure compressing the spinal cord was found at the level between the first and second lumbar vertebra. The cyst showed hypointense on a T1-weighted image with rim enhancement and hyperintense on a T2-weighted image. The cystic lesion was removed through right-side hemilaminectomy. In the histopathological examination, evenly distributed fibroblasts and collagenous stroma with several cartilaginous materials were seen. The neurological signs of the right hindlimb were successfully recovered within a week in follow-up neurological examination and showed normal gait at 6 months after surgery.

Gadolinium Complexes of Bifunctional Diethylenetriaminepentaacetic Acid (DTPA)-bis(amides) as Copper Responsive Smart Magnetic Resonance Imaging Contrast Agents (MRI CAs)

  • Nam, Ki Soo;Park, Ji-Ae;Jung, Ki-Hye;Chang, Yongmin;Kim, Tae-Jeong
    • Bulletin of the Korean Chemical Society
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    • v.34 no.10
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    • pp.2900-2904
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    • 2013
  • We present the synthesis and characterization of DTPA-bis(histidylamide) (1a), DTPA-bis(aspartamide) (1b), and their gadolinium complexes of the type $[Gd(L)(H_2O)]$ (2a:L = 1a; 2b:L = 1b). Thermodynamic stabilities and $R_1$ relaxivities of 2a-b compare well with Omniscan$^{(R)}$, a well-known commercial, extracellular (ECF) MRI CA which adopts the DTPA-bis(amide) framework for the chelate: $R_1$ = 5.5 and 5.1 $mM^{-1}$ for 2a and 2b, respectively. Addition of the Cu(II) ion to a solution containing 2b triggers relaxivity enhancement to raise $R_1$ as high as 15.3 $mM^{-1}$, which corresponds to a 300% enhancement. Such an increase levels off at the concentration beyond two equiv. of Cu(II), suggesting the formation of a trimetallic ($Gd/Cu_2$) complex in situ. Such a relaxivity increase is almost negligible with Zn(II) and other endogenous ions such as Na(I), K(I), Mg(II), and Ca(II). In vivo MR images and the signal-to-noise ratio (SNR) obtained with an aqueous mixture of 2b and Cu(II) ion in an 1:2 ratio demonstrate the potentiality of 2 as a copper responsive MRI CA.

A case of congenital neurocutaneous melanosis (선천성 신경피부멜라닌증 1례)

  • Ha, Sang Kyun;Lee, Jae Myoung;Kim, Eun Ryoung;Hwang, Ho;Lee, Hong Tak
    • Clinical and Experimental Pediatrics
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    • v.49 no.2
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    • pp.212-216
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    • 2006
  • Neurocutaneous melanosis is a rare congenital syndrome characterized by the presence of large or multiple congenital melanocytic nevi and benign pigment cell tumors of the leptomeninges. Neurocutaneous melanosis is thought to represent an error in the morphogenesis of embryonal neuroectoderm. We experienced a neonate who presented with giant, dark colored pigmented nevi covering chest, abdomen, neck and arms, with satellite lesions. Magnetic resonance image showed a nodular hyperintense lesion in the amygdala of the right temporal lobe, and T1-weighted images showed hyperintensities in the adjacent leptomeninges. We report a rare case of neurocutaneous melanosis with a brief review of related literature.

Effective Gray-white Matter Segmentation Method based on Physical Contrast Enhancement in an MR Brain Images (MR 뇌 영상에서 물리기반 영상 개선 작업을 통한 효율적인 회백질 경계 검출 방법)

  • Eun, Sung-Jong;Whangbo, Taeg-Keun
    • Journal of Digital Contents Society
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    • v.14 no.2
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    • pp.275-282
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    • 2013
  • In medical image processing field, object recognition is usually carried out by computerized processing of various input information such as brightness, shape, and pattern. If the information mentioned does not make sense, however, many limitations could occur with object recognition during computer processing. Therefore, this paper suggests effective object recognition method based on the magnetic resonance (MR) theory to resolve the basic limitations in computer processing. We propose the efficient method of robust gray-white matter segmentation by texture analysis through the Susceptibility Weighted Imaging (SWI) for contrast enhancement. As a result, an average area difference of 5.2%, which was higher than the accuracy of conventional region segmentation algorithm, was obtained.

Anti-Cancer Effect of Ginsenoside F2 against Glioblastoma Multiforme in Xenograft Model in SD Rats

  • Shin, Ji-Yon;Lee, Jung-Min;Shin, Heon-Sub;Park, Sang-Yong;Yang, Jung-Eun;KimCho, So-Mi;Yi, Tae-Hoo
    • Journal of Ginseng Research
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    • v.36 no.1
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    • pp.86-92
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    • 2012
  • The glioblastoma multiforme (GBM) is the most common malignant brain tumor in adults. Despite combination treatments of radiation and chemotherapy, the survival periods are very short. Therefore, this study was conducted to assess the potential of ginsenoside $F_2$ (F2) to treat GBM. In in vitro experiments with glioblastoma cells U373MG, F2 showed the cytotoxic effect with $IC_{50}$ of 50 ${\mu}g/mL$ through apoptosis, confirmed by DNA condensation and fragmentation. The cell population of cell cycle sub-G1 as indicative of apoptosis was also increased. In xenograft model in SD rats, F2 at dosage of 35 mg/kg weight was intravenously injected every two days. This reduced the tumor growth in magnetic resonance imaging images. The immunohistochemistry revealed that the anticancer activity might be mediated through inhibition of proliferation judged by Ki67 and apoptosis induced by activation of caspase-3 and -8. And the lowered expression of CD31 showed the reduction in blood vessel densities. The expression of matrix metalloproteinase-9 for invasion of cancer was also inhibited. The cell populations with cancer stem cell markers of CD133 and nestin were reduced. The results of this study suggested that F2 could be a new potential chemotherapeutic drug for GBM treatment by inhibiting the growth and invasion of cancer.

Methods to determine the volume of infrapatellar fat pad as an indicator of anterior cruciate ligament tear

  • Cheruvu, B.;Tsatalis, J.;Laughlin, R.;Goswami, T.
    • Biomaterials and Biomechanics in Bioengineering
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    • v.3 no.1
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    • pp.27-35
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    • 2016
  • Anterior knee pain is a major problem among adolescents and young adults especially those who participates in sports. The most common pathogenesis of anterior knee pain can arise from compression and shear forces in the patellofemoral joint. It is also caused by impingement of infrapatellar fat pad. Fat pad impingement can occur when the fat pad becomes swollen and inflamed due to a direct blow or chronic irritation. As a result, the bottom tip (or inferior pole) of the patella can pinch the fat pad. One of the many causes of swollen fat pad can be secondary to anterior cruciate ligament (ACL) injury. The aim of this study was to compare the infrapatellar fat pad volume in patients with acute ACL injury and a group of age-, gender-, and activity- matched controls with intact ligament. Axial magnetic resonance (MR) images have been performed on 32 patients with torn ACL and 40 control patients. The volume of the fat pad was measured digitally from MR image by using a 3d Reconstruction software, ellipsoidal approximation, and a MATLAB code. The results were compared between patients with torn ACL and control group. Patients with a torn ACL had a significantly larger fat pad than the controls (P=0.01). There was no significant difference between the methods used to measure the infrapatellar fat pad volume (P=0.83-0.87). Thus, lesions of the infrapatellar fat pad is often associated with ACL injury.