Publications by authors named "Myong-Hun Hahm"

Background: Radiation necrosis (RN) after stereotactic radiosurgery (SRS) in brain metastases has been extensively evaluated, and RN is correlated with various risk factors. However, no study comprehensively analyzed the correlation between RN and the border zones of the brain that are vulnerable to ischemia. We hypothesized that patients with tumors in the border zone are at high risk of RN.

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Objectives: To investigate the predictability of synthetic relaxometry for neurodevelopmental outcomes in premature infants and to evaluate whether a combination of relaxation times with clinical variables or qualitative MRI abnormalities improves the predictive performance.

Methods: This retrospective study included 33 premature infants scanned with synthetic MRI near or at term equivalent age. Based on neurodevelopmental assessments at 18-24 months of corrected age, infants were classified into two groups (no/mild disability [n = 23] vs.

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BACKGROUND Vanishing white matter disease (VWMD) - also known as childhood ataxia with central nervous system hypomyelination - is one of the most commonly inherited white matter diseases in children. Notably, a course of chronic progressive disease with episodes of rapid and major stress-induced neurological deterioration, such as fever and minor head trauma, is a typical clinical feature of VWMD. The combination of clinical features with specific magnetic resonance imaging findings, including diffuse and extensive white matter lesions with rarefaction or cystic destruction, could recommend a genetic diagnosis.

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The sphenoid bone is a complex structure in terms of its embryological origin. At birth, the sphenoid sinus is nonpneumatized. Arrested pneumatization of the sphenoid sinus is considered a normal anatomic variant but may be mistaken for disease in imaging studies.

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Hepatic encephalopathy (HE) is a severe neuropsychiatric abnormality in patients with either acute or chronic liver failure. Typical brain magnetic resonance imaging findings of HE are bilateral basal ganglia high signal intensities due to manganese deposition in chronic liver disease and hyperintensity in T2, fluid-attenuated inversion recovery, or diffusion-weighted imaging (DWI) with hemispheric white matter changes including the corticospinal tract. Low values on apparent diffusion coefficient mapping of the affected area on DWI, indicating cytotoxic edema, can be observed in acute HE.

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The aims of the study are to evaluate idiopathic normal-pressure hydrocephalus (INPH)-related cerebral blood flow (CBF) abnormalities and to investigate their relation to cortical thickness in INPH patients. We investigated cortical CBF utilizing surface-based early-phase F-florbetaben (E-FBB) PET analysis in two groups: INPH patients and healthy controls. All 39 INPH patients and 20 healthy controls were imaged with MRI, including three-dimensional volumetric images, for automated surface-based cortical thickness analysis across the entire brain.

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Purpose: To validate the use of synthetic magnetic resonance imaging (SyMRI) volumetry by comparing with child-optimized SPM 12 volumetry in 3 T pediatric neuroimaging.

Methods: In total, 106 children aged 4.7-18.

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The anomalous hyperplastic anterior choroidal artery (AchoA) is a rare anomaly due to incomplete distal annexation between the primitive AchoA and posterior cerebral artery (PCA). It is often misdiagnosed or misunderstood as a duplicated or fetal type PCA because of its supply distribution. In addition, its aneurysm incidence is much higher than the overall aneurysm incidence of AchoA.

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Contralateral C7 (CC7) nerve transfer surgery was shown to significantly improve the spasticity condition and the motor function of paralyzed arms. However, the involvement of the white matter tract in the recovery process is not well established. We here investigated the possible biologic explanation for this phenomenon.

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The transversus abdominis plane (TAP) block is an ideal pain control method used in surgeries that require abdominal wall incisions through the injection of an anesthetic solution into the plane between the internal oblique muscle and transversus abdominis muscle. Herein, we report an 83-year-old man who was diagnosed with idiopathic normal pressure hydrocephalus (iNPH) and underwent lumboperitoneal shunt surgery (LPS). The TAP block was performed before LPS, and the numerical rating scale for pain was 0 at day 1 after the surgery.

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Background: Although recent studies show vitamin D deficiency is associated with cognitive decline, urinary incontinence, and gait instability, there has been no study on the effect of vitamin D on idiopathic normal pressure hydrocephalus (iNPH) characterized by the classic symptom triad of cognitive decline, urinary incontinence, and gait instability. We investigated the clinical significance of vitamin D in patients with iNPH.

Methods: Between 2017 and 2020, 44 patients who underwent ventriculoperitoneal shunt surgery were divided into low (< 15 ng/mL) and high (≥ 15 ng/mL) vitamin D groups according to the concentration of 25(OH)D, an effective indicator of vitamin D status.

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Background: Doctors with various specializations and experience order brain computed tomography (CT) to rule out intracranial hemorrhage (ICH). Advanced artificial intelligence (AI) can discriminate subtypes of ICH with high accuracy.

Objective: The purpose of this study was to investigate the clinical usefulness of AI in ICH detection for doctors across a variety of specialties and backgrounds.

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We present a rare case of spindle cell oncocytoma (SCO) of the sella turcica with malignant histologic features and rapid progression. A 42-year-old woman experienced bilateral blurred vision and was preoperatively misdiagnosed as having a pituitary macroadenoma on magnetic resonance imaging. After surgery, SCO was diagnosed by the histopathologic features of interlacing fascicles of spindle tumor cells with finely granular, eosinophilic cytoplasm.

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Background: Radiomics is a promising field in oncology imaging. However, the implementation of radiomics clinically has been limited because its robustness remains unclear. Previous CT and PET studies suggested that radiomic features were sensitive to variations in pixel size and slice thickness of the images.

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Window settings to rescale and contrast stretch raw data from radiographic images such as Computed Tomography (CT), X-ray and Magnetic Resonance images is a crucial step as data pre-processing to examine abnormalities and diagnose diseases. We propose a distant-supervised method for determining automatically the best window settings by attaching a window estimator module (WEM) to a deep convolutional neural network (DCNN)-based lesion classifier and training them in conjunction. Aside from predicting a flexible window setting for each raw image, we statistically identify the top four window settings by calculating the mean and standard deviations for the entire dataset.

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Background: Current chemoradiation regimens for locally advanced cervical cancer are fairly uniform despite a profound diversity of treatment response and recurrence patterns. The wide range of treatment responses and prognoses to standardized concurrent chemoradiation highlights the need for a reliable tool to predict treatment outcomes. We investigated pretreatment magnetic resonance (MR) imaging features of primary tumor and involved lymph node for predicting clinical outcome in cervical cancer patients.

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Background: To investigate the difference in the measured diameter of subsolid lung adenocarcinomas of thin-section computed tomography (TSCT) and pathology according to presence of emphysema.

Methods: A total of 268 surgically resected pathologic T1 or T2 adenocarcinomas visualized as subsolid nodules (SSNs) on TSCT were analyzed in 252 patients. Two observers measured the greatest diameters of the whole tumor (WTsize) and solid tumor (STsize) on TSCT in lung windows, classified nodules as part-solid or nonsolid, and recorded the presence of regional emphysema.

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Retrograde type A aortic dissection (RTAD) following thoracic endovascular aortic repair is a devastating complication associated with high mortality rates. In particular, a deployed endograft in a bird-beak formation in an acute curve of the aortic arch can induce injury to the fragile aortic wall, with the subsequent development of RTAD. Here, we describe an extremely rare case of RTAD caused by fracture of the bare spring of the thoracic endograft for type A aortic dissection.

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Rationale And Objectives: Mucinous adenocarcinoma (MAC) is a distinct histologic variant subtype of lung adenocarcinomas. However, detailed radiologic findings and prognostic factors are still poorly understood. Thus, this study aimed to investigate the prognostic value of quantitative volumetric analysis of the computed tomography images of patients with MAC after.

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A 22-year-old man was admitted with gradually aggravating stereotypic head movement with hypomania. Brain magnetic resonance imaging showed a large suprasellar arachnoid cyst extending into the third ventricle, with obstructive hydrocephalus, characteristic of bobble-head doll syndrome. Endoscopic fenestration of the suprasellar arachnoid cyst was performed.

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This report describes a case of a 40-year-old female patient with concurrent invasive ductal carcinoma of the breast and malignant follicular lymphoma, initially suspected to be metastatic breast cancer. During the initial evaluation of invasive ductal carcinoma of right breast, multiple lymphadenopathies were noted throughout the body on ultrasonography and positron emission tomography/computed tomography images. Clinically, metastatic breast cancer was suggested, and the patient was administered chemotherapy, including hormonal therapy.

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The fat-rich anterior mediastinum could be a sensitive window for monitoring minute changes in vascularity induced by systemic vasculitis. To evaluate this hypothesis, an analysis of anterior mediastinal fat in patients with Behçet's disease and a control group was conducted. This study included 43 patients diagnosed with Behçet's disease within the last 11 years who underwent CT scan; 55 patients were selected as a control population.

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