• Title/Summary/Keyword: Digital subtraction

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A Study on the design of First Residue to Second Residue Converter for Double Residue Number System (DRNS용 SRTFR 변환기 설계에 관한 연구)

  • Kim, Young-Sung
    • The Journal of Information Technology
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    • v.12 no.2
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    • pp.39-47
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    • 2009
  • Residue Number System is used for the purpose of increasing the speed of processing in the many application parts of Image Processing, Computer Graphic, Neural Computing, Digital Signal Processing etc, since it has the characteristic of parallelism and no carry propagation at each moduli. DRNS has the twice RNS Conversion, it is used to decreases the size of the operator in RNS. But it has a week point on the Second Residue to First Residue Conversion time. So, in this paper SRTFR(Second Residue to First Residue) Converter using MRC(Mixed Radix Conversion) is designed to decrease the size of RTB(Residue to Binary) Converter. Since the proposed SRTFR Converter using MRC(Mixed Rdix Convertion) has a pipeline processing. Also, modular operation is applied to at each partitioned SAM(Subtraction and Addition) and MA(Multiplication and addition). In the following study, the more effective design on MA is needed.

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Arteriovenous Malformation of the Scalp : Efficacy of Computed Tomography Angiography

  • Moon, Kang-Seok;Yoon, Seok-Mann;Shim, Jai-Joon;Yun, Il-Gyu
    • Journal of Korean Neurosurgical Society
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    • v.38 no.5
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    • pp.396-398
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    • 2005
  • We report a rare case of scalp arteriovenous malformation[AVM]. A 55-year-old woman presented with a pulsatile palpable mass on her left temporo-parietal scalp. She complained of insomnia because of bruit, which was audible when she lay on her left side. Computed tomography angiography[CTA] for the scalp vessel showed AVM on the left temporo-parietal region. Multiple enlarged arteries, such as the superficial temporal artery, posterior auricular artery, and occipital artery, were directly connected to the elongated dilated superficial temporal vein. Digital subtraction angiography also showed similar results. Fistulous portions were clearly delineated on both modalities. Surgical excision of the malformations, including feeding arteries and the draining vein, resulted in immediate relief of the symptoms. Usefulness of CTA in the diagnosis of vascular lesions on the scalp was emphasized.

Digital Subtraction Angiography

  • Ko, Seong-Jin
    • Journal of radiological science and technology
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    • v.6 no.1
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    • pp.21-26
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    • 1983
  • DSA는 해상능(解像能)에 있어서는 일반적(一船的)인 혈관(血管) 조영술(造影術)에 비해서 다소 못미치지만 소량(小量)의 조영제(造影劑)로도 혈관구조(血管構造)를 잘 관찰(觀察)할 수 있으며 큰 차이의 조직(組織)두께차를 적절히 수용(受容)할 수 있으며 필름의 소모도 적게 되었다. DSA는 경동맥검사(頸動脈檢査)에 가장 중요한 위치를 차지하며 많이 시행(施行)되고 있다. 혈관(血管)의 모양을 변화(變化) 시키는 여러 질환에서 혈관(血管)상태나 혈류(血流)의 변화(變化), 내경(內經)도 알수 있다. 최근에는 흉부(胸部)나 후두(喉頭) 등(等)에도 적용하여 일반검사(一般檢査)와 비교(比較)하여 좋은 결과(結果)를 얻고있다. 또 확대촬영(擴大撮影)이나 입체촬영(立體撮影)까지 응용(應用)하여 좋은 성적을 얻고 있다. DSA는 보고자 하는 혈관상(血管像)만을 단시간에 볼 수 있고 유연성(柔軟性)이 있고 비침습성(非侵襲性)(noninvasive)이며 간단한 검사방법(檢査方法)이라는 점 등(等)에서 매우 유용(有用)한 검사(檢査)라 하겠다.

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An Aneurysm Developing on the Infundibulum of Posterior Communicating Artery : Case Report and Literature Review

  • Jang, Woo-Youl;Joo, Sung-Pil;Kim, Tae-Sun;Kim, Jae-Hyoo
    • Journal of Korean Neurosurgical Society
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    • v.40 no.4
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    • pp.293-295
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    • 2006
  • Infundibular dilatation is funnel-shaped symmetrical enlargement that occurs at the origin of cerebral arteries and which is apparent on 7 to 25% of normal angiograms. Infundibular dilatation is frequently considered a normal anatomic variation of no pathologic significance. The authors report a case in which an aneurysm developed on an infundibular dilatation of the posterior communicating artery [PComA]. A 72-year-old woman presented with severe headache, nausea, and vomiting. Digital subtraction angiography showed a saccular aneurysm arising from the origin of the left PComA. Operative findings revealed the aneurysm and infundibular widening of the right PComA. The aneurysm was successfully obliterated. Whether infundibular dilatation is a pre-aneurysmal state or a benign dilatation is controversial. However, we believe infundibular dilatation of the PComA in this case may have served as a pre-aneurysmal lesion.

Urgent Intracranial Carotid Artery Decompression after Penetrating Head Injury

  • Kim, Seong Joon;Park, Ik Seong
    • Journal of Korean Neurosurgical Society
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    • v.53 no.3
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    • pp.180-182
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    • 2013
  • We describe a case of intracranial carotid artery occlusion due to penetrating craniofacial injury by high velocity foreign body that was relieved by decompressive surgery. A 46-year-old man presented with a penetrating wound to his face. A piece of an electric angular grinder disc became lodged in the anterior skull base. Computed tomography revealed that the disc had penetrated the unilateral paraclinoid and suprasellar areas without flow of the intracranial carotid artery on the lesion side. The cavernous sinus was also compromised. Removal of the anterior clinoid process reopened the carotid blood flow, and the injection of glue into the cavernous sinus restored complete hemostasis during extraction of the fragment from the face. Digital subtraction angiography revealed complete recanalization of the carotid artery without any evidence of dissection. Accurate diagnosis regarding the extent of the compromised structures and urgent decompressive surgery with adequate hemostasis minimized the severity of penetrating damage in our patient.

A Case of Probable Moyamoya Disease (Unilateal Moyamoya Disease) Coexisting Arteriovenous Malformation

  • Shin, Doog-Soo;Song, Kwan-Young;Hong, Hyun-Jong;Kong, Min-Ho
    • Journal of Korean Neurosurgical Society
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    • v.42 no.1
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    • pp.49-52
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    • 2007
  • The authors report a unique case of unilateral Moyamoya disease with a rare combination of arteriovenous malformation (AVM) who presented with intracerebral hemorrhage (ICH). A 50-year-old man suffered from sudden onset of mental deterioration and right hemiparesis. Brain computed tomography (CT) showed intracerebral hemorrhage on left thalamus. Brain CT angiography and cerebral digital subtraction angiography (DSA) revealed AVM combined with unilateral moyamoya disease involving left middle cerebral artery (MCA) and choroid plexus in left lateral ventricle. Intraventricular hemorrhage and hydrocephalus were managed conservatively. A rare case of unilateral Moyamoya disease accompanied by a cerebral arteriovenous malformation is described and discussed with review of pertinent literature.

Moyamoya-Like Vasculopathy in Neurosarcoidosis

  • Ko, Jun-Kyeung;Lee, Sang-Weon;Choi, Chang-Hwa
    • Journal of Korean Neurosurgical Society
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    • v.45 no.1
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    • pp.50-52
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    • 2009
  • A 31-year-old man presented with dull headache and memory disturbance lasting for one week. Computed tomographic scans revealed acute hydrocephalus. The cerebrospinal fluid contained 53 leukocytes/$mm^3$, with a mononuclear preponderance and no erythrocytes. Magnetic resonance imaging revealed hydrocephalus and leptomeningeal enhancement. Magnetic resonance angiography and digital subtraction angiography showed supraclinoid occlusion of the right internal carotid artery, which resembled unilateral moyamoya disease. Neuroendoscopic biopsy of a lesion in the septum pellucidum revealed noncaseating granulomas, which was consistent with sarcoidosis. The patient was successfully managed with intravenous methylprednisolone and ventriculoperitoneal shunting. To our knowledge, this is the first case of moyamoya-like vasculopathy associated with neurosarcoidosis.

Giant Atherosclerotic Aneurysm of Common Femoral Artery (총대퇴동맥의 동맥경화성 거대 동맥류 -1례 보고-)

  • 장인석;김성호
    • Journal of Chest Surgery
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    • v.29 no.10
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    • pp.1157-1159
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    • 1996
  • Atherosclerotic giant aneurysm of the common femoral artery is rare. Because the patients who lose timing of the operation face amputation or death, the surgical treatment must be performed at the proper time. A 72-old man was admitted to the hospital because of a 20-days history of pulsatile growing mass on his left groin. After the diagnosis of giant aneurysm of the common femoral artery by computerized tomography and digital subtraction angiography, an emergent operation was performed. Both deep and superficial femoral arteries were successfully reconstructed with Gore-tex grafts after aneurysmectomy. The pathology of the aneurysm was proved to be atherosclerosis.

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A Case of Intraosseous Dural Arteriovenous Fistulas Involving Diploic Vein Treated with Transarterial Onyx Embolization

  • Shim, Jae-Hyun;Yoon, Seok-Mann;Shim, Jai-Joon;Kim, Ra-Sun
    • Journal of Korean Neurosurgical Society
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    • v.50 no.3
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    • pp.260-263
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    • 2011
  • Intracranial dural arteriovenous fistulas (DAVFs) are abnormal arteriovenous connections that lie within the dura. Intraosseous DAVFs involving diploic venous system are extremely rare. A 46-year-old woman presented with headache and right pulsatile tinnitus for three weeks. The tinnitus started after yelling. Digital subtraction angiography revealed DAVF within the basal portion of right parietal bone along the middle meningeal artery (MMA) groove. The fistula was fed by frontal branch of right MMA and drained into right transverse sigmoid sinus junction through dilated middle meningeal vein. The intraosseous DAVF involving diploic vein was successfully obliterated with Onyx embolization via transarterial route.