Despite the advent and growing availability of magnetic resonance imaging,the imaging modality of choice in the acute care of stroke patients in many institutions remains computed tomography.The hyperdense artery sign...Despite the advent and growing availability of magnetic resonance imaging,the imaging modality of choice in the acute care of stroke patients in many institutions remains computed tomography.The hyperdense artery sign is the earliest marker of acute ischemic stroke.In this short review,we discuss the pathology,incidence,clinical aspects,imaging findings,significance and future questions that need to be addressed concerning this important sign.展开更多
The purpose of this study was to determine whether 5-mm axial CT images can sufficiently depict the hyperdense middle cerebral artery (MCA) sign in patients with acute brain ischemia. Materials and Methods: A retrospe...The purpose of this study was to determine whether 5-mm axial CT images can sufficiently depict the hyperdense middle cerebral artery (MCA) sign in patients with acute brain ischemia. Materials and Methods: A retrospective review of 92 cases of ischemic brain infarction confirmed nine patients showing hyperdense MCA signs. CT images were acquired on a 64-slice helical scanner. Images were reconstructed into contiguous 5-mm axial, coronal and sagittal datasets. The first CT scan images of the patients with hyperdense MCA signs and an equal number of CT scans without hyperdense MCA signs inserted at random were analyzed in a blinded review. The presence of the hyperdense MCA sign in M1 segments was recorded. Round regions of interest (ROI) were placed over the M1 segments of the MCAs and the attenuation values in Hounsfield units (HU) were measured on the sagittal and axial images. Results: Nine patients showed a hyperdense MCA sign. They consisted of 4 male and 5 female (mean age, 74.3 years;age range, 45 - 88 years). On the blinded review, hyperdense MCA signs were detected on axial images in 7 patients. In four of the 7 patients, the hyperdense MCA sign was more conspicuous on sagittal images than that on axial images. Hyperdense MCA sign was detected on sagittal images of all 9 patients and exclusive to the sagittal images in two patients. The ROI study showed higher attenuation for the affected MCA on sagittal images (46 - 65 HU) than that on axial images (36 - 54 HU). Conclusion: In patients with acute brain ischemia, 5-mm axial CT images cannot sufficiently depict the hyperdense MCA sign. Sagittal images may be superior to axial images for identifying the sign.展开更多
Allergic bronchopulmonary aspergillosis(ABPA) is a complex hypersensitivity syndrome triggered against antigens of Aspergillus fumigatus,a fungus that most commonly colonizes the airways of patients with bronchial ast...Allergic bronchopulmonary aspergillosis(ABPA) is a complex hypersensitivity syndrome triggered against antigens of Aspergillus fumigatus,a fungus that most commonly colonizes the airways of patients with bronchial asthma and cystic fibrosis.It presents clinically with refractory asthma,hemoptysis and systemic manifestations including fever,malaise and weight loss.Radiologically,it presents with central bronchiectasis and recurrent episodes of mucus plugging.The mucus plugs in ABPA are generally hypodense but in up to 20% of patients the mucus can be hyperdense on computed tomography.This paper reviews the literature on the clinical significance of hyperattenuated mucus in patients with ABPA.展开更多
Osteopoikilosis is a rare benign sclerotic bone dysplasia. The disease which usually develops asymptomatically is coincidentally diagnosed with direct radiographs. Our subject, a 52-year-old male was admitted to our p...Osteopoikilosis is a rare benign sclerotic bone dysplasia. The disease which usually develops asymptomatically is coincidentally diagnosed with direct radiographs. Our subject, a 52-year-old male was admitted to our policlinic two days ago due to turning of his left ankle causing pain and swelling on his left ankle. We asked for bilateral direct radiograph of left ankle. The left ankle radiograph indicates multiple, small oval/round hyperdense sclerotic regions. As a result of available clinical finding and radiological viewing, the patient was diagnosed with osteopoikilosis.展开更多
Introduction: The appendix is identified as blind ending tubular structure arising from caecum and has variable intraluminal contents and position. Acute appendicitis is one of the common indications for emergency ima...Introduction: The appendix is identified as blind ending tubular structure arising from caecum and has variable intraluminal contents and position. Acute appendicitis is one of the common indications for emergency imaging studies. Aim: To describe the importance of appendix hyperattenuation and densities. Material and Methods: Contrast enhanced computed tomography images of abdomen from 120 patients with surgically/pathological proven acute appendicitis, were examined retrospectively. The images were reviewed in axial, coronal and sagittal reformations for assessing the intraluminal contents (hyperdensity and appendicolith), maximum transverse diameter and single wall thickness of appendix, periappendiceal fat stranding and other parameters related to acute appendicitis. In addition, reviewing 100 pre- and post-contrast CT scans of other abdominal conditions as a control group for documenting hyperdense appendix, appendicolith and other signs of appendicitis. Results: The hyperdense appendix sign was found in 5 patients in our study, not found in any patient of the control group (P value = 0.039, is statistically), appendicolith was found in 25% in patients with acute appendicitis, in 3% in control group (statistically significant, p < 0.0001). Conclusion: The hyperdense appendix and appendicolith have strong association with acute appendicitis in the appropriate clinical setting.展开更多
文摘Despite the advent and growing availability of magnetic resonance imaging,the imaging modality of choice in the acute care of stroke patients in many institutions remains computed tomography.The hyperdense artery sign is the earliest marker of acute ischemic stroke.In this short review,we discuss the pathology,incidence,clinical aspects,imaging findings,significance and future questions that need to be addressed concerning this important sign.
文摘The purpose of this study was to determine whether 5-mm axial CT images can sufficiently depict the hyperdense middle cerebral artery (MCA) sign in patients with acute brain ischemia. Materials and Methods: A retrospective review of 92 cases of ischemic brain infarction confirmed nine patients showing hyperdense MCA signs. CT images were acquired on a 64-slice helical scanner. Images were reconstructed into contiguous 5-mm axial, coronal and sagittal datasets. The first CT scan images of the patients with hyperdense MCA signs and an equal number of CT scans without hyperdense MCA signs inserted at random were analyzed in a blinded review. The presence of the hyperdense MCA sign in M1 segments was recorded. Round regions of interest (ROI) were placed over the M1 segments of the MCAs and the attenuation values in Hounsfield units (HU) were measured on the sagittal and axial images. Results: Nine patients showed a hyperdense MCA sign. They consisted of 4 male and 5 female (mean age, 74.3 years;age range, 45 - 88 years). On the blinded review, hyperdense MCA signs were detected on axial images in 7 patients. In four of the 7 patients, the hyperdense MCA sign was more conspicuous on sagittal images than that on axial images. Hyperdense MCA sign was detected on sagittal images of all 9 patients and exclusive to the sagittal images in two patients. The ROI study showed higher attenuation for the affected MCA on sagittal images (46 - 65 HU) than that on axial images (36 - 54 HU). Conclusion: In patients with acute brain ischemia, 5-mm axial CT images cannot sufficiently depict the hyperdense MCA sign. Sagittal images may be superior to axial images for identifying the sign.
文摘Allergic bronchopulmonary aspergillosis(ABPA) is a complex hypersensitivity syndrome triggered against antigens of Aspergillus fumigatus,a fungus that most commonly colonizes the airways of patients with bronchial asthma and cystic fibrosis.It presents clinically with refractory asthma,hemoptysis and systemic manifestations including fever,malaise and weight loss.Radiologically,it presents with central bronchiectasis and recurrent episodes of mucus plugging.The mucus plugs in ABPA are generally hypodense but in up to 20% of patients the mucus can be hyperdense on computed tomography.This paper reviews the literature on the clinical significance of hyperattenuated mucus in patients with ABPA.
文摘Osteopoikilosis is a rare benign sclerotic bone dysplasia. The disease which usually develops asymptomatically is coincidentally diagnosed with direct radiographs. Our subject, a 52-year-old male was admitted to our policlinic two days ago due to turning of his left ankle causing pain and swelling on his left ankle. We asked for bilateral direct radiograph of left ankle. The left ankle radiograph indicates multiple, small oval/round hyperdense sclerotic regions. As a result of available clinical finding and radiological viewing, the patient was diagnosed with osteopoikilosis.
文摘Introduction: The appendix is identified as blind ending tubular structure arising from caecum and has variable intraluminal contents and position. Acute appendicitis is one of the common indications for emergency imaging studies. Aim: To describe the importance of appendix hyperattenuation and densities. Material and Methods: Contrast enhanced computed tomography images of abdomen from 120 patients with surgically/pathological proven acute appendicitis, were examined retrospectively. The images were reviewed in axial, coronal and sagittal reformations for assessing the intraluminal contents (hyperdensity and appendicolith), maximum transverse diameter and single wall thickness of appendix, periappendiceal fat stranding and other parameters related to acute appendicitis. In addition, reviewing 100 pre- and post-contrast CT scans of other abdominal conditions as a control group for documenting hyperdense appendix, appendicolith and other signs of appendicitis. Results: The hyperdense appendix sign was found in 5 patients in our study, not found in any patient of the control group (P value = 0.039, is statistically), appendicolith was found in 25% in patients with acute appendicitis, in 3% in control group (statistically significant, p < 0.0001). Conclusion: The hyperdense appendix and appendicolith have strong association with acute appendicitis in the appropriate clinical setting.
