• Journal of radiological science and technology
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• v.34 no.2
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• pp.105-116
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• 2011

In this study, we present the measurements of effective dose from CT of head & neck region. A series of dose measurements in anthropomorphic Rando phantom was conducted using a radio photoluminescent glass rod dosimeter to evaluate effective doses of organs of head and neck region from the patient. The experiments were performed with respect to four anatomic regions of head & neck: optic nerve, pons, cerebellum, and thyroid gland. The head & neck CT protocol was used in the single scan (Brain, 3D Facial, Temporal, Brain Angiography and 3D Cervical Spine) and the multiple scan (Brain+Brain Angiography, Brain+3D Facial, Brain+Temporal, Brain+3D Cervical spine, Brain+3D Facial+Temporal, Brain+3D Cervical Spine+Brain Angiography). The largest effective dose was measured at optic nerve in Brain CT and Brain Angiography. The largest effective dose was delivered to the thyroid grand in 3D faical CT and 3D cervical spine, and to the pons in Temporal CT. In multiple scans, the higher effective dose was measured in the thyroid grand in Brain+3D Facial, Brain+3D Cervical Spine, Brain+3D Facial+Temporal and Brain+3D Cervical Spine+Brain Angiography. In addition, the largest effective dose was delivered to the cerebellum in Brain CT+Brain Angiography CT and higher effective dose was delivered to the pons in Brain+Temporal CT. The results indicate that in multiple scan of Brain+3D Cervical Spine+Brain Angiography, effective dose was 2.52 mSv. This is significantly higher dose than the limitation of annual effective dose of 1 mSv. The effective dose to the optic nerve was 0.31 mSv in Brain CT, which shows a possibility of surpassing the limitation of 1 mSv by furthre examination. Therefore, special efforts should be made in clinical practice to reduce dose to the patients.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.1
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• pp.64-68
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• 2004

Brain death is defined as the irreversible cessation of all brain function. The diagnosis of brain death is primarily based on a careful neurological examination demonstrating unresponsiveness, absent of brain stem reflexes, and no respiratory activity. Several conditions which may mimic brain death must be excluded. In some cases investigations such as electroencephalography, angiography, transcranial doppler or evoked potentials can contribute to the diagnosis. The brief review will introduce medical technologist and clinician to the key issues in the definition and management of brain death.

• Journal of Korean Neurosurgical Society
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• v.48 no.6
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• pp.524-527
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• 2010

Temporary disruption of the blood-brain barrier (BBB) after cerebral angiography is presumably caused by nonionic radiographic contrast medium (CM). We hereby report a case of 58-year-old woman who developed decreased mentality, global aphasia and aggravated right hemiparesis after cerebral angiography. Brain CT examination demonstrated gyriform enhancement throughout the left cerebral cortex and thalamus. MR diffusion did not reveal acute infarction. MR angiography did not show any stenosis, spasm or occlusion at the major cerebral vessels. Follow-up CT scan after 1 day did not show any gyriform enhancement. Worsened neurologic signs and symptoms were improved completely after 7 days. In the present study, disruption of the BBB with contrast medium after angiography seems to be the causative factor of transient neurologic deterioration.

• Journal of Veterinary Science
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• v.24 no.5
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• pp.65.1-65.9
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• 2023

Background: Bone subtraction computed tomography angiography (BSCTA) is a useful alternative technique for improving visualization of vessels surrounded by skull bone. However, no studies have compared computed tomography angiography (CTA) and BSCTA for improving the visibility of canine cerebral blood vessels. Objectives: To evaluate the potential benefit of BSCTA for better delineation of brain arteries of the circle of Willis (CoW) in dogs by comparing BSCTA with non-subtraction computed tomography angiography (NSCTA). Methods: Brain CTA was performed for nine healthy beagle dogs using a bolus tracking method with saline flushing. A total dose of 600 mgI/kg of contrast agent with an iodine content of 370 mgI/mL was injected at a rate of 4 ml/s. Bone removal was achieved automatically by subtracting non-enhanced computed tomography (CT) data from contrast CT data. Five main intracranial arteries of the CoW were analyzed and graded on a scale of five for qualitative evaluation. Results: Scores of basilar artery, middle cerebral artery, and rostral cerebral artery in the BSCTA group were significantly higher than those in the NSCTA group (p = 0.001, p = 0.020, and p < 0.0001, respectively). Scores of rostral cerebellar artery (RcA) and caudal cerebral artery (CCA) did not differ significantly between the two groups. However, scores of RcA and CCA in the BSCTA group were higher than those in the NSCTA group. Conclusions: BSCTA improved visualization of intracranial arteries of the CoW with close contact to bone. Thus, it should be recommended as a routine scan method in dogs suspected of having brain vessel disease.

• Proceedings of the Korea Society for Simulation Conference
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• 2003.11a
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• pp.201-206
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• 2003

In clinical practice, CT Angiography is a powerful technique for the visualziation of blood flow in arterial vessels throughout the body. However CT Angiography images of blood vessels anywhere in the body may be fuzzy if the patient moves during the exam. In this paper, we propose a novel technique for removing global motion artifacts in the 3D space. The proposed methods are based on the two key ideas as follows. First, the method involves the extraction of a set of feature points by using a 3D edge detection technique based on image gradient of the mask volume where enhanced vessels cannot be expected to appear, Second, the corresponding set of feature points in the contrast volume are determined by correlation-based registration. The proposed method has been successfully applied to pre- and post-contrast CTA brain dataset. Since the registration for motion correction estimates correlation between feature points extracted from skull area in mask and contrast volume, it offers an accelerated technique to accurately visualize blood vessels of the brain.

• Journal of radiological science and technology
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• v.41 no.2
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• pp.123-128
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• 2018

Recently, the use of contrast agents has been increasing as a broader range of tests and dynamic tests have become common due to the development of equipment and imaging techniques such as Multi-Detector CT. However, the side effects of using contrast agents have been reduced by the development of non-ionic contrast agents, but they are still occurring often. The purpose of this study was to propose a method to minimize the side effect of contrast agent by using the amount of contrast agent injected to the brain angiography test to suppress excessive use of contrast agent and analyze the amount of contrast agent. Patients who were prescribed Brain Angiography due to cerebrovascular disease, According to the results of the comparison of the results obtained by dividing into 4 groups of 10ml each according to the amount of contrast medium injected with contrast agent according to the BMI of the patient, BA and SNR were not different between groups, and even if the amount of contrast injection was reduced, there was no problem in the evaluation of CT angiography through 3D reconstruction. This result shows that even if the contrast medium is injected into the blood vessels of the patient first and then the contrast medium is used as the physiological saline solution, the contrast medium is reduced by 40% it can be expected to minimize.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.257-260
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• 2009

Intraventricular hemorrhage long after successful encephaloduroarterio synangiosis (EDAS) is very rare. The effect of revascularization surgery for preventing hemorrhagic event of moyamoya disease remains controversial. We report a 17-year-old female with intracerebral hemorrhage and intraventricular hemorrahge 10 years after successful EDAS. Even though cerebral vessels angiography showed good collateral circulations without specific weak points, a cerebral hemorrhage could occur in patient with ischemic type of moyamoya disease long after successful indirect bypass operations. Good collateralization of cerebral angiography or magnetic resonance perfusion image after indirect bypass surgery would ensure against ischemic symptoms, not a hemorrhage. And, thus a life-time follow-up strategy might be necessary even if a good collateral circulation has been established.

• Journal of Korean Neurosurgical Society
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• v.59 no.4
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• pp.420-424
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• 2016

The spinal dural arteriovenous fistula (SDAVF) is rare, presenting with progressive, insidious symptoms, and inducing spinal cord ischemia and myelopathy, resulting in severe neurological deficits. If physicians have accurate and enough information about vascular anatomy and hemodynamics, they achieve the good results though the surgery or endovascular embolization. However, when selective spinal angiography is unsuccessful due to neurological deficits, surgery and endovascular embolization might be failed because of inadequate information. We describe a patient with a history of vasospasm during spinal angiography, who was successfully treated by spinal stereotactic radiosurgery using Novalis system.

• Journal of The Korean Radiological Technologist Association
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• v.25 no.1
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• pp.121.1-121.1
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• 1999

• Journal of Korean Neurosurgical Society
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• v.40 no.6
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• pp.423-427
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• 2006

Objective : Postoperative brain swelling after resection of olfactory groove meningiomas by bifrontal interhemispheric transbasal approach is a knotty subject. Pathogenesis and predictive factors were investigated to prevent the problem. Methods : Eighteen patients of olfactory groove meningiomas who had undergone surgery were enrolled and retrospectively analyzed using their clinical and radiological data. Bifrontal inter hemispheric transbasal approach was used in all patients. Magnetic resonance imaging and transfemoral cerebral angiography were available for investigation in 18 and 14 patients respectively. Postoperative clinical course, tumor volume, peritumoral edema, tumor supplying vessels, and venous drainage patterns were carefully investigated in relation to postoperative brain swelling. Results : Seven patients [39%] developed clinically overt brain swelling after surgery. Among them, 4 patients had to undergo decompression surgery. In three patients, attempted bone flap removal was done by way of prevention of increased intracranial pressure resulted from intractable brain swelling and two of them eventually developed brain swelling which could be recovered without sequellae. Abnormal frontal base venous channel observed in preoperative angiography was significant predictive factor for postoperative brain swelling [p=0.031]. However, tumor volume, peritumoral edema, and existence of pial tumor supplying vessels from anterior cerebral arteries were failed to show statistical significances. Conclusion : To prevent postoperative brain swelling in olfactory groove meningioma surgery, unilateral approach to preserve frontal base venous channels or temporal bone flap removal is recommended when it is indicated.