• Imaging Science in Dentistry
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• 제31권4호
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• pp.241-245
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• 2001

A 16-year-old female was admitted to Wonkwang dental hospital with a chief complaint of painful ulceration on right buccal mucosa around mandibular 3rd molar area. Computed tomography and magnetic resonance imaging showed relative large soft tissue mass on the infratemporal fossa and masseter muscle region. By the feature of T1-weighted and T2-weighted of MR imaging, we suspected this mass as a kind of myogenic sarcoma. Histopathological and immunohistochemical studies established a definitive diagnosis of embryonal rhabdomyosarcoma. A review of the literature was also presented.

• Parasites, Hosts and Diseases
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• 제51권3호
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• pp.349-352
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• 2013

We present here a 44-year-old male patient with hydatid disease who was referred to our hospital due to dyspnea and chest pain for the last 2 month before admission. Using echocardiography and contrast-enhanced computed tomography the heart hydatid was diagnosed. However, hydatid disease of the interventricular septum is rare; particularly, the involvement of mitral apparatus with mitral regurgitation (MR) is an exceptionally rare presentation. Early diagnosis and an integrated treatment strategy are crucial. Surgical excision was performed and the patient had an uneventful recovery and follow-up at 3 months.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.572-575
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• 2005

A novel pneumatic artificial muscle actuator (PAM actuator), which has achieved increased popularity to provide the advantages such as high strength and high power/weight ratio, low cost, compactness, ease of maintenance, cleanliness, readily available and cheap power source, inherent safety and mobility assistance to humans performing tasks, has been regarded during the recent decades as an interesting alternative to hydraulic and electric actuators. In order to realize satisfactory control performance, a variable damper Magneto Rheological Brake (MRB), Is equipped to the Joint of the manipulator. Superb mixture of conventional PID controller and a phase plane switching control method brings us a novel controller. This proposed controller is appropriate for a kind of plants with nonlinearity, uncertainties and disturbances. The experiments were carried out in practical PAM manipulator and the effectiveness of the proposed control algorithm was demonstrated through experiments, which had proved that the stability of the manipulator can be improved greatly in a high gain control by using MRB with phase plane switching control method and without regard for the changes of external inertia loads.

• 치과방사선
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• 제22권1호
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• pp.29-37
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• 1992

The temporomandibular joint was evaluated using magnetic resonance imaging using a urface coil in 11 patients having reciprocal clicking or locking and compared with the normal joint in five subjects. Serial multisection 3㎜-thick parasagittal, paracoronal, and axial image on both closing and opening mouth were obtained with a 1.5 Tesla MR system and surface coil using CSMEMP, GRASS, MPGR, powerful extensions of fast imaging that is currently under clinical evaluation. MR images obtained were analized correlating with the theory of internal derangement. The obtained results were as follows: 1. The serial findings of structures in joint were determined on the serially sectioned images of joint with reciprocal clicking or locking by CSMEMP and MPGR on closing mouth. 2. The delta shaped white images of synovial fluid in the glenoid fossa and on the posterior surface of condyle were revealed on the parasagittal images by MPGR on opening mouth as in the normal joints. 3. The white image of joint fluid surrounding meniscus was recognized on the paracoronal image by GRASS on opening mouth as in the normal joints. 4. In joints having temporomandibular dysfunction the smooth image of displaced meniscus was recognized, but otherwise in the normal joints the image of muscle was noted on the paracoronal image sectioned at the anterior portion of condyle by GRASS. 5. The more thickened fascial plane between superior and inferior belly of lateral pterygoid muscle was not recognizable in joints having temporomandibular dysfunction than in the normal joints.

• Journal of Korean Neurosurgical Society
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• 제57권2호
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• pp.94-99
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• 2015

Objective : The purpose of our study was to assess prevalence of carotid intraplaque hemorrhage (IPH) and associations between territorial acute infarction and IPH on magnetization-prepared rapid acquisition with gradient-echo (MPRAGE) in patients with acute neurologic symptoms. Methods : 83 patients with suspected acute neurologic symptoms were evaluated with both brain diffusion weighted imaging (DWI) and carotid MPRAGE sequences. Carotid plaque with high signal intensity on MPRAGE of >200% that of adjacent muscle was categorized as IPH. We analyzed the prevalence of IPH and its correlation with territorial acute infarction. Results : Of 166 arteries, 39 had a carotid artery plaque. Of these arteries, 26 had carotid artery stenosis less than 50%. In all carotid arteries, MR-depicted IPH was found in 7.2% (12/166). High-signal intensity on DWI was found in 17.5% (29/166). Combined lesion with ipsilateral high-signal intensity on DWI and IPH on carotid MPRAGE sequence was found in 6 lesions (6/166, 3.6%). Of patients with carotid artery plaque, MR-predicted IPH was found in 30.8% (12/39) and match lesions with high-signal intensity on DWI and MPRAGE was found in 15.4% (6/39). MR-predicted IPH was significantly higher prevalence in high-grade stenosis group (p=0.010). Relative risk between carotid MPRAGE-positive signal and ipsilateral high-signal intensity on DWI in arteries with carotid artery plaques was 6.8 (p=0.010). Conclusion : Carotid MPRAGE-positive signal in patients was associated with an increased risk of territorial acute infarction as detected objectively by brain DWI. The relative risk of stroke was increased in high-grade stenosis categories.

• Journal of Korean Neurosurgical Society
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• 제67권2호
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• pp.249-256
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• 2024

The Leksell frame-based transcerebellar approach was proposed with the arc support frame attached upside down to the Z coordinate. This study presented practical tips and considerations for obtaining adequate tissue samples for deep-seated cerebellar lesions or lower brainstem lesions specifically those accessible via the cerebellar peduncle. For practical insights, the Leksell coordinate frame G was fixed to prevent the anterior screw implantation within the temporalis muscle, to avoid interference with the magnetic resonance (MR)-adapter, and taking into account the magnetic field of MR in close proximity to the tentorium. After mounting of indicator box, the MR imaging evaluation should cover both the indicator box and the infratentorial region that deviated from it. The coordinates [X, Y, Za, Arc⁰, Ringa⁰] obtained from Leksell SurgiPlan^® software (Elekta, Stockholm, Sweden) with arc 0⁰ located on the patient's right side were converted to [X, Y, Zb=360-Za, Arc⁰, Ringb⁰=Ringa⁰-180⁰]. The operation was performed in the prone position under general anesthesia in four patients with deep cerebellar (n=3) and brainstem (n=1) tumors. The biopsy results showed two cases of diffuse large B-cell lymphoma, one metastatic braintumor and one glioblastoma. One patient required frame repositioning as a complication. Drawing upon the methodology outlined in existing literature, we anticipate that imparting supplementary expertise could render the stereotactic biopsy of infratentorial tumors more consistent and manageable for the practitioner, thereby facilitating adequate tissue samples and minimizing patient complications.

• Journal of Chest Surgery
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• 제30권6호
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• pp.598-606
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• 1997

1994년 9월부러 1995년 8월까지 일년동안 부천 세종병원에서 시행된 승모판막질환 수술은 총 136례였으 며 이중 인공판륜을 사용하여 판막성형술을 시행된 44례를 대상으로 평가하였다 이 44례의 평균 연령은 38.2세(범위: 5세~63세)였으며 남성이 18례 여성이 26례였다, 사용된 인공판륜은 Carpentier ring이 32례, Dmm ring 이 12례였다. 판막질환의 원인은 류마치스가 30례(68%), 퇴행성 질환에 기인한 것이 13례(30%)였으며, 1례는 선천성 승 모판 부전증이었다. 판막질환의 형태로 보면 승모판막부전증이 33례(76%),승모판 협착증이 2 례(5%), 승모판 협착부전증이 9례(19%) 있었다. Carpentier의 기능적 분류는 I형이 5례(11%), II형이 24례(55%), III형이 4례(9%) 있었으며, II형과 III형의 혼합형이 11례(25%)에서 관찰되었고, 매 환자당 평균 3.7가지의 병변이 있었다. 승모판에 시행한 수술 수기는 전례에서 인공판륜성형술을 시행하였으며 한 환자 당 평균 3.4가지의 수기 를 사용하였다. 수술 사망은 2례에서 발생하였으며, 수술 후 승모판 부전증이 진행되어 2주에 시행한 재수술이 일 례 있 었다. 12개월의 추적 관찰에서 수술 전후의 NYHA 기능적 鈞畢\ulcorner평균 3.0에서 1.3으로 개선되었다. 심장 초음파 검사에서 술후의 승모판 면적은 2.07$\pm$0.11 cm2(평균 $\pm$ 표준오차)이었으며, 좌심실 수축력의 호전을 보였고, 판막부전의 정도는 전혀 판막부전 소견이 없어진 경우가 23례(53%), 경미한 폐쇄부전이 있는 경우가 18례(42%)였고, II도 부전의 소견을 보인 례가 2례(5%) 있었다.

• Tuberculosis and Respiratory Diseases
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• 제44권5호
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• pp.1040-1050
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• 1997

연구배경 : 만성폐쇄성폐질환 환자의 치료에 널리 적용되고 호흡재활치료는 폐기능을 호전시키지는 못하지만 호흡곤란 등의 증상과 운동능력을 호전시키는 것으로 알려져 있다. 그러나 이런 운동능력 개선의 기전은 여러 각도에서 해석되고 있다. 저자들은 $^{31}P$ MRS를 이용하여 만성 폐질환 환자들을 호흡재활치료 전후 전박근의 대사 변화를 관찰함으로써, 호흡재활치료 후 운동능력호전에 골격근 대사개선을 기여할 가능성을 조사하였다. 방 법 : 총 9명의 만성 폐질환을 갖고 있는 남자 환지들을 대상으로 하였고 이들의 평균 연령은 $58{\pm}11$세였으며, 이들의 기저 질환은 만성폐쇄성폐질환 8예 및 폐유육종증 1예였다. 호흡재활치료는 근육강화운동, 답차운동(treadmill walking), 자전거 운동(stationary bicycle riding) 및 상지 운동력측정계(arm ergometer)를 이용한 상지운동으로 구성했으며, 호흡재활치료 전후로 폐기능 검사, 운동부하 검사, 상하지의 지구력 측정 및 6분 보행거리 검사를 실시하였다. $^{31}P$ MRS검사를 치료 전후 전박근을 대상으로 안정시, 운동시 및 20분간의 회복시에 시행하여 세포내 산소성 인산화 능력을 반영하는 Pi/PCr의 비와 pHi(intracellular pH)를 구하여 비교하였다. 결 과 : 호흡재활치료 후 환자의 폐기능과 가스 교환의 호전은 없었으나, 운동지구력 및 보행능력은 현저한 호전을 보였으며 최대산소섭취량은 증가하는 경향을 보였고, 동 운동량에서의 분당환기량은 감소하는 경향을 나타내었다. $^{31}P$ MRS를 이용하여 재활치료 전후의 골격근 대사를 비교해 본 결과, 치료 후 운동시 및 극심한 피로상태에서의 pHi는 유의하게 높았고 산소성 인산화 과정을 반영하는 지표인 Pi/PCr는 감소하는 경향을 보였으나 안정시 및 회복기의 골격근 대사과정은 변화가 없었다. 결 론 : 이상으로 만성 폐질환 환자에서 6주간의 호흡재활치료는 운동지구력 및 보행 호전시켰으며 이러한 운동능력 호전에는 골격근 대사의 개선으로 초래된 골격근 세포내의 산성화 지연으로 인한 환기량의 감소가 기여할 사료되었다.

• Investigative Magnetic Resonance Imaging
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• 제25권4호
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• pp.323-331
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• 2021

Purpose: To investigate the diagnostic criteria of T1-weighted imaging (T1W) and time-of-flight (TOF) imaging for detecting intraplaque hemorrhage (IPH) of a vertebrobasilar artery (VBA) compared with simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) imaging. Materials and Methods: Eighty-seven patients with VBA atherosclerosis who underwent high resolution MR imaging for evaluation of VBA plaque were reviewed. The presence and location of VBA plaque and IPH on SNAP were determined. The signal intensity (SI) of the VBA plaque on T1W and TOF imaging was manually measured and the SI ratio against adjacent muscles was calculated. The receiver-operating characteristic (ROC) curve was used to compare the diagnostic accuracy for detecting VBA IPH. Results: Of 87 patients, 67 had IPH and 20 had no IPH on SNAP. The SI ratio between VBA IPH and temporalis muscle on T1W was significantly higher than that in the no-IPH group (235.9 ± 16.8 vs. 120.0 ± 5.1, P < 0.001). The SI ratio between IPH and temporalis muscle on TOF was also significantly higher than that in the no-IPH group (236.8 ± 13.3 vs. 112.8 ± 7.4, P < 0.001). Diagnostic efficacies of SI ratios on TOF and TIW were excellent (AUC: 0.976 on TOF and 0.964 on T1W; cutoff value: 136.7% for TOF imaging and 135.1% for T1W imaging). Conclusion: Compared with SNAP, cutoff levels of the SI ratio between VBA plaque and temporalis muscle on T1W and TOF imaging for detecting IPH were approximately 1.35 times.

• Investigative Magnetic Resonance Imaging
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• 제22권2호
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• pp.94-101
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• 2018

Purpose: To determine the value of the appearance of the high signal intensity halo sign for detecting carotid intraplaque hemorrhage (IPH) on maximum intensity projection (MIP) of time-of-flight (TOF) MR angiography (MRA), based on high signal intensity on magnetization-prepared rapid acquisition with gradient-echo (MPRAGE) sequencing. Materials and Methods: A total of 78 carotid arteries in 65 patients with magnetization-prepared rapid acquisition gradient-echo (MPRAGE) positive on carotid plaque MR imaging were included in this study. High-resolution MR imaging was performed on a 3.0-T scanner prior to carotid endarterectomy or carotid artery stenting. Fast spin-echo T1- and T2-weighted axial imaging, TOF, and MPRAGE sequences were obtained. Carotid plaques with high signal intensity on MPRAGE > 200% that of adjacent muscle on at least two consecutive slices were defined as showing IPH. Halo sign of high signal intensity around the carotid artery was found on MIP from TOF MRA. Continuous and categorical variables were compared among groups using the Mann-Whitney test and Fisher's exact tests. Results: Of these 78 carotid arteries, 53 appeared as a halo sign on the TOF MRA. The total IPH volume of patients with a positive halo sign was significantly higher than that of patients without a halo sign ($75.0{\pm}86.8$ vs. $16.3{\pm}18.2$, P = 0.001). The maximum IPH axial wall area in patients with a positive halo sign was significantly higher than that of patients without a halo sign ($11.3{\pm}9.9$ vs. $3.7{\pm}3.6$, P = 0.000). Conclusion: High signal intensity halo of IPH on MIP of TOF MRA is associated with total volume and maximal axial wall area of IPH.