Publications by authors named "Dae Hyun Hwang"

Objective: This study aimed to investigate whether a deep learning reconstruction (DLR) method improves the image quality, stent evaluation, and visibility of the valve apparatus in coronary computed tomography angiography (CCTA) when compared with filtered back projection (FBP) and hybrid iterative reconstruction (IR) methods.

Materials And Methods: CCTA images of 51 patients (mean age ± standard deviation [SD], 63.9 ± 9.

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Background: The demand for homogeneous and higher vascular contrast enhancement is critical to provide an appropriate interpretation of abnormal vascular findings in coronary computed tomography angiography (CTA).

Purpose: To evaluate the effect of various contrast media concentrations (Iohexol-370, Iohexol-300, Iohexol-240) and image reconstructions (filtered back projection [FBP], hybrid iterative reconstruction [IR], and deep learning reconstruction [DLR]) on coronary CTA.

Material And Methods: A total of 63 patients referred for coronary CTA between July and October 2021 were enrolled in this prospective study, and they randomly received one of three contrast media.

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To evaluate the ability of a commercialized deep learning reconstruction technique to depict intracranial vessels on the brain computed tomography angiography and compare the image quality with filtered-back-projection and hybrid iterative reconstruction in terms of objective and subjective measures. Forty-three patients underwent brain computed tomography angiography, and images were reconstructed using three algorithms: filtered-back-projection, hybrid iterative reconstruction, and deep learning reconstruction. The image noise, computed tomography attenuation value, signal-to-noise ratio, and contrast-to-noise ratio were measured in the bilateral cavernous segment of the internal carotid artery, vertebral artery, basilar apex, horizontal segment of the middle cerebral artery and used for the objective assessment of the image quality among the three different reconstructions.

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Xanthogranulomatous inflammation is a rare inflammatory reaction, characterized by lipid-laden macrophages, known as xanthomas, in histopathologic examination. Aggressive xanthogranulomatous inflammation often manifests as local infiltration but does not affect distant organs unless combined with rare systemic diseases. We report a case of focal xanthogranulomatous pyelonephritis (XGP) associated with severe xanthogranulomatous cholecystitis.

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Angioleiomyomas are benign smooth muscle tumors that originate from the tunica media of veins and arteries. They can occur anywhere in the body, but the preferential location of these tumors is the lower extremities. We describe a rare case of rectal angioleiomyoma and present our findings obtained by using computed tomography, magnetic resonance imaging, and histopathological analysis.

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A 61-year-old male patient with pyogenic spondylodiscitis and epidural and psoas abscesses underwent posterior decompression, debridement, and instrumented fusion, followed by anterior debridement and reconstruction. Sudden onset flank pain was diagnosed 7 weeks postoperatively and was determined to be a pseudoaneurysm located at the aorta inferior to the renal artery and superior to the aortic bifurcation area. An endovascular stent graft was applied to successfully treat the pseudoaneurysm.

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Objective: The purpose of our study is to retrospectively determine the diagnostic role of (18)F-FDG PET/CT at the primary lesion site in burned patients with chronic nonhealing ulcers who are suspected of having Marjolin ulcers.

Materials And Methods: Thirty-three burn scar contractures with nonhealing chronic ulcer in 28 patients were included in this study. The lesions were sorted into two groups: 22 squamous cell carcinomas and one basal cell carcinoma were assigned to group 1 (Marjolin ulcer), and 10 lesions of chronic ulcer with inflammation and fibrosis were assigned to group 2.

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We present a case of successful retrieval of an intracranial stent using a snare wire. A 52-year-old woman presented with left border zone infarction. On cerebral angiography, the C6 segment of the left internal carotid artery (ICA) showed significant stenosis.

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Purpose: We evaluated the usefulness of intracranial stent implantation for treating patients with atherosclerotic stenosis and with recurrent, ischemic, neurological symptoms despite having undergone medical therapy.

Materials And Methods: Between March 2004 and April 2010, we attempted intracranial, stent-assisted angioplasty in 77 patients with 85 lesions (anterior circulation 73 cases, posterior circulation 12 cases) and who had ischemic neurological symptoms with more than 50% major cerebral artery stenosis. We analyzed the results regarding the technical success rate, complication rate, and restenosis rate during the mean 29.

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We report on a 66-year-old woman with a posterior circulation stroke that occurred after bronchial artery embolization (BAE) due to post-tuberculous bronchiectasis. Stroke is a rare complication of BAE and is usually thought to be caused by inadvertent embolization via a bronchial artery-pulmonary vein shunt. However, the possibility of thromboembolic stroke should be considered, because of the patient's possible underlying anatomical variations or atherothrombosis.

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Paraplegia secondary to spinal cord infarction is a recognized complication of open thoracic and thoracoabdominal aortic aneurysm (TAA) repair. TAA is serious and unpredictable condition. Therefore, aortic repair requires thorough information on managing the potential complications will facilitate improve control the problem.

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Background: A high-voltage electrical burn is often associated with deep muscle injuries. Hidden, undetected deep muscle injuries have a tendency for progressive tissue necrosis, and this can lead to major amputations or sepsis. MRI has excellent soft tissue contrast and it may aid in differentiating the areas of viable deep muscle from the areas of non-viable deep muscle.

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