Chia-Yuen Chen

Background Cerebral blood flow (CBF) and the morphology of the cerebral arteries are important for characterizing cerebrovascular disease. Silent magnetic resonance angiography (Silent MRA) is a MRA technique focusing on arterial structural delineation. This study was conducted to investigate the correlation between Silent MRA and CBF quantificatio...

Vessel flow quantification by two-dimensional (2D) phase-contrast magnetic resonance imaging (PC-MRI) using a three-dimensional (3D) magnetic resonance angiography (MRA) model to measure cerebral blood flow has unclear analytical reliability. The present study aimed to determine the inter- and intra-rater reliability of quantitative vessel-flow PC-...

Rationale and Objectives: In this study, we assessed the radiation dose to the lens and the impacts of various eye shields using either a fixed or modulated tube current. Materials and Methods: Patients undergoing head computed tomography (CT) examinations were recruited, and each was randomly assigned to one of five imaging groups, either without...

Rationale and objectives: In this study, we assessed the radiation dose to the lens and the impacts of various eye shields using either a fixed or modulated tube current. Materials and methods: Patients undergoing head computed tomography (CT) examinations were recruited, and each was randomly assigned to one of five imaging groups, either witho...

Background: Deep-seated brain tumors can be difficult to differentiate. Three tumor types (primary central nervous system lymphoma [PCNSL], high-grade glioma, and metastatic brain tumors), identified by susceptibility-weighted imaging, have different relationships with small medullary veins, and these relationships can be used to enhance diagnosti...

Rationale: Human papillomavirus (HPV)-related oropharyngeal cancer is becoming more common, the primary cancer AQ4 usually occult and appearing only as cystic cervical lymph node (LN) metastasis. Distinguishing between a benign cystic lesion and cystic LN metastasis is challenging given their similar radiologic and histologic appearances. Patient...

This special report introduces native flow quantitative imaging for evaluating stroke risk. Moreover, the advantage of combining three imaging techniques [magnetic resonance angiography (MRA), phase-contrast (PC) flow imaging, and arterial spin-labeling imaging] is shown to be beneficial for responding to ischemia and preserving viable neurons. The...

Olfactory dysfunction is related to several clinical neurodegenerative diseases, such as Alzheimer’s disease, multiple sclerosis, degenerative ataxias, Parkinson’s disease, etc. Owing to the individual difference in sensory adaption of human smell function, the olfactory responses usually present large inter-individual difference and change over ti...

Respiration is a crucial vital sign to indicate acidotic state of human body. In this study, we have developed a Holo-Hilbert spectral analysis (HHSA)-based approach to detect subject’s respiration frequency from wrist photoplethysmogram (PPG) signals. The HHSA is a two-layer EMD architecture which firstly decomposes the original signal into intrin...

Background Multiple rounds of head computed tomography (CT) scans increase the risk of radiation-induced lens opacification. Purpose To investigate the effects of CT eye shielding and topogram-based tube current modulation (TCM) on the radiation dose received by the lens and the image quality of nasal and periorbital imaging. Material and Methods...

To evaluate malignant middle cerebral artery (MCA) infarction (defined as space-occupying edema in more than 50% to 75% of the MCA territory) on magnetic resonance imaging (MRI) with susceptibility-weighted imaging (SWI) sequence and assess the usefulness of SWI findings, diffusion-weighted imaging (DWI) findings, and apparent diffusion coefficient...

Predicting the risk of further infarct growth in stroke patients is critical to therapeutic decision making. We aimed to predict early infarct growth and clinical outcome from prominent vessel sign (PVS) identified on the first susceptibility-weighted image (SWI) after acute stroke. Twenty-two patients with middle cerebral artery (MCA) infarction h...

Background/Purpose There has been no individual ultrasound feature of having high accuracy for diagnosis of thyroid malignancy. In this study, we aimed to establish feature-oriented criteria to characterize benign thyroid nodules that do not require ultrasound (US)-guided fine needle aspiration (FNA). Methods We reviewed 374 patients with thyroid...

Sacrococcygeal teratoma (SCT) is a neoplasm derived from more than one primitive germ cell layer. SCTs have rarely been reported in adults. We present a case of a 17-year-old youth who complained of a painful mass over his left buttock.The mass had been growing gradually since his childhood. Magnetic resonance imaging showed a well-defined soft-tis...

http://www.ajnr.org/content/quiz/10312011qz

Non-Hodgkin's lymphoma which occasionally involves the central nervous system, occurs more often in high-grade cases and implicates a poor prognosis. Leptomeningeal metastases may present as multiple cranial nerve involvements. Diagnosis is achieved by recognizing the clinical manifestations, followed by neuroradiologic studies and laboratory exami...

http://www.ajnr.org/content/quiz/07182011qz

Primary squamous cell carcinoma (SCC) of the thyroid gland is an extremely rare neoplasm with fewer than 55 reported cases.1 The cancer, which resembles anaplastic carcinoma, tends to be advanced at presentation, with rapid progression and a poor prognosis.2 Calcification is a common finding on thyroid imaging. Microcalcification is known to be ass...

Lemierre syndrome is characterized by postanginal septicemia and internal jugular vein thrombophlebitis with secondary septic emboli, typically to the lungs. The central nervous system (CNS) is rarely involved. To present a case of Lemierre syndrome featuring cerebral subdural and epidural empyemas. This case report describes the case of a 17-year-...

Malignant fibrous histiocytoma (MFH) in the heart is rare. We present a case of a 38-year-old woman with histologically confirmed MFHs in the left atrium, liver and bone. The patient presented with shortness of breath and right shoulder pain. A plain radiograph showed an osteolytic lesion at the neck of the humerus on the right side. A computed tom...

To assess the safety, yield and clinical utility of percutaneous transgastric computed tomography (CT)-guided biopsy of pancreatic tumor using large needles, in selected patients. We reviewed 34 CT-guided biopsies in patients with pancreas mass, of whom 24 (71%) had a direct path to the mass without passing through a major organ. The needle passed...

Hemangioblastoma of the conus medullaris with MRI has not been reported before. A 75-year-old man had a history of falling due to weakness of his left lower limb. MRI revealed a well-defined oval mass in the conus medullaris. The tumor had an isointense signal relative to spinal cord on T1-weighted images, hyperintense signal areas intermixed with...

The purpose of the present paper was to evaluate the clinical and chest radiographic features of pediatric patients with serologically proven Mycoplasma pneumoniae pneumonia (mycoplasma pneumonia). The clinical records and chest radiographs of 39 consecutive patients (19 male, 20 female; age 3-13 years) with serologically positive IgG and IgM mycop...

Gluteal intramuscular myxomas with MR images have not been reported before. A 45-year-old man presented with a palpable mass in his right buttock for several months. Magnetic resonance imaging showed an intramuscular cystic lesion with homogeneous signal intensity at the right gluteus muscle, and the mass had thin peripheral enhancement after gadol...

We presented a case of a 63-year-old man with type 2 diabetes mellitus and end-stage renal disease on hemodialysis. Precontrast CT images showed atrophy of kidneys bilaterally and calcification of the abdominal aorta, small branches of bilateral renal arteries and small arteries of the pelvis, including the internal pudendal artery and penile arter...

We describe a patient with a right anterior choroidal artery territory infarction and an inconspicuous left visual defect. The anterior choroidal artery is a unique artery of the cerebral circulation. The occlusion of this artery can result in dysfunction of motor, sensory, and visual systems with only rare involvement of higher cortical function....

Cerebral subarachnoid hemorrhage may result from rupture of saccular aneurysms at uncommon location [excluding the anterior communicating artery (ACOM)] of the anterior cerebral artery (ACA). The purpose of this study was to evaluate the usefulness of helical computed tomography angiography (CTA) in detection and characterization of intracranial an...

Tumoral calcinosis-like metastatic calcification in a patient with uremia on dialysis has rarely been reported in the radiological literatures. This report describes the radiographic, scintigraphic, ultrasound, and CT findings of this condition in a 54-year-old man who had a clinical history of renal dialysis for 6 years. Elevation of serum phospha...

A case report of an epidermoid cyst in the conus medullaris with characteristic magnetic resonance imaging (MRI) findings. To describe an epidermoid cyst in the conus medullaris with characteristic MRI findings and point out these findings that correlated well with histologic findings. Taiwan. A 49-year-old man who suffered from pain and weakness i...

Elderly patients who have osteoporosis and a cancer history with backache and vertebral fractures are diagnostic challenges. We present a case of an 87-year-old man who complained of severe low-back pain with radiation to the lower limbs and weakness of the lower limbs. The patient had had a fall on a bus 1 month before admission. The patient also...

Heterotopic brain presenting as a giant, growing, single locular cyst at the parapharyngeal space has not been reported before, to our knowledge. We present such a case, with MR imaging findings, in a 13-month-old girl. A well-demarcated giant cystic mass was noted in the left parapharyngeal space from the skull base to the submandibular region. Ai...

Although application of proton magnetic resonance (MR) spectroscopy in the diagnosis of brain tumors has been reported, the role of this technique as guidance for targeting biopsy of brain tumors is not well established. The usefulness and limitations of predicting tumor proliferative activity and pathological grading of brain gliomas based on samp...

A total of 20 patients with centrally embolized Port-A catheter fragments underwent the percutaneous retrieval procedures at our hospital. The causes of the dislodgement of these catheters included bad connection between the port and catheter, angulation or distortion at the anastomosis site, severing the catheter during insertion and removal of th...

From April 1994 to June 2002, 17 catheter fragments and two guidewires became intravascular foreign bodies during venous catheterization at our hospital. Retrievals of these 19 foreign bodies were performed percutaneously with loop snare techniques (10 cases), Dormia basket retrievers (eight cases) and grasping forceps (one case). The percutaneous...