Comparison of emergency cranial CT interpretation between radiology residents and neuroradiologists: transverse versus three-dimensional images.

PURPOSE: Three-dimensional (3D) reformatted images provide a more inclusive representation of abnormalities than transverse images in cranial computed tomography (CT). The purpose of this study was to assess the value of 3D reformations for radiology residents in the interpretation of emergency cranial CTs. MATERIALS AND METHODS: In total, 218 consecutive patients who underwent emergency cranial CT scans with 3D reformation were included in this retrospective study. Four blinded readers (three radiology residents and a neuroradiologist) interpreted the transverse and 3D images in two separate sessions. Each reader assessed 1) abnormal finding(s) and the confidence score(s) (5-point scale) for transverse and 3D images, 2) added value score of 3D images (5-point scale), and 3) interpretation time for both transverse and 3D images. We analyzed discordance between each radiology resident and the neuroradiologist on a lesion-by-lesion basis. RESULTS: In total, 509 lesions were detected in 218 patients. Discordance rates between the three residents and the neuroradiologist were 11.4%-20.2% (mean, 15.0%) and 8.8%-16.9% (mean, 12.1%) in the interpretation of transverse and 3D images, respectively. Confidence scores were higher for 3D images than for transverse images for all readers. The added value scores for the 3D images were relatively higher for the inexperienced residents. Interpretation times for 3D images were significantly higher than for transverse images for all readers. CONCLUSION: The 3D reformations assist radiology residents in the interpretation of emergency cranial CT examinations.

Value of CT angiography for the detection of intracranial vascular lesions in patients with acute severe headache.

OBJECTIVES: To retrospectively investigate the prevalence and characteristics of intracranial vascular lesions in patients with acute severe headache with the use of CT angiography (CTA). METHODS: We systematically searched for neurologically intact patients with acute severe headache and normal unenhanced head CT. The study group consisted of 512 patients; 251 male; mean age 46.2 ± 12.4 years. All patients underwent CTA between 1 day and 2 months after the headache attack. CTA images were interpreted by two experienced neuroradiologists for the presence of vascular lesions. RESULTS: Thirty-four (6.6 %) of the 512 patients had intracranial vascular lesions on CTA, including 33 aneurysms (2 patients had 2 aneurysms each), 2 moyamoya disease and 1 arterial dissection. No gender- or age-related differences were found. Aneurysms arose most commonly on the internal carotid artery (n = 12), followed by the anterior communicating artery (n = 7), and the middle cerebral artery (n = 7). Maximal diameters ranged from 2.0 to 13.1 mm (mean, 3.9 ± 2.6 mm). CONCLUSIONS: CTA is a feasible tool for diagnosing intracranial vascular lesions in patients with acute severe headache. The prevalence of vascular lesions in our series was 6.6 %, which is higher than that predicted in the general population. KEY POINTS: • Unruptured cerebral aneurysms may be a cause of acute severe headache • CTA assesses intracranial vascular lesions in patients with acute severe headache • The prevalence of vascular lesions in our series of patients was 6.6 %

Characteristics and trends of radiology research: a survey of original articles published in AJR and Radiology between 2001 and 2010.

PURPOSE: To determine the characteristics and trends of the original articles published in two major American radiology journals, AJR American Journal of Roentgenology (AJR) and Radiology, between 2001 and 2010. MATERIALS AND METHODS: This was a retrospective bibliometric analysis that did not involve human subjects and was exempt from institutional review board approval. All 6542 original articles published in AJR and Radiology between 2001 and 2010 were evaluated. The following information was abstracted from each article: radiologic subspecialty, radiologic technique used, type of research, sample size, study design, statistical analysis, study outcome, declared funding, number of authors, affiliation of the first author, and country of the first author. In addition, all the variables examined were presented along with the trend over time. RESULTS: The most common subspecialty of study was abdominal (1219 of 6542, 18.6%), followed by vascular/interventional (804 of 6542, 12.3%). A total of 3744 (57.2%) original articles used magnetic resonance (MR) imaging or computed tomography (CT), 5495 (84.1%) were clinical research articles, 3060 (46.8%) had sample size of more than 50, 4087 (62.5%) were retrospective, 4714 (72.1%) performed statistical analysis, 6225 (95.2%) showed positive study outcome, 4784 (73.1%) were not funded, 3942 (60.3%) had four to seven authors, and 5731 (87.6%) were written by the primary author who was from a department of radiology or radiology-related specialties. The United States published 45.5% (2975 of 6542) of the articles, followed by Japan (n = 525, 8.0%), Germany (n = 485, 7.4%), and South Korea (n = 455, 7.0%). In the time trend analysis, the following variables showed a significantly positive trend: cardiac subspecialty, CT and MR imaging as the radiologic techniques, type of research as other (nonbasic, nonclinical), sample size of more than 50, four to seven as the number of authors, medicine-related department of the first author, and South Korea and Italy as countries of the first author. On the other hand, pediatric subspecialty, combined (basic and clinical) type of research, and number of authors fewer than four showed a significantly negative trend. CONCLUSION: The bibliometric analysis of the AJR and Radiology journals with articles published between 2001 and 2010 revealed characteristics and trends of the current radiology research that may provide useful information to researchers and editorial staff in radiology.

Central venous stenosis of left versus right arm: its prevalence and effects on image quality in CT of the neck.

OBJECTIVE: The purpose of this study was (1) to evaluate the prevalence of the left and right central venous stenosis by measuring the narrowest area and (2) to assess the effects of the central venous stenosis on perivenous artifacts and reflux of contrast material, in CT of the neck. MATERIALS AND METHODS: Images of a total of 443 CT of the neck with an injection of contrast material into the left (n = 249) or right (n = 194) arm were retrospectively reviewed. The maximum stenosis area in the central vein ipsilateral to the injection side was measured in each patient. We also graded the perivenous artifacts and reflux of contrast material with 4-point scale. These results were compared between patients with right arm injection and those with left arm injection. RESULTS: The maximum stenosis area in the left arm was significantly smaller than that in the right arm. The stenosis was most frequently identified at the medial clavicular region. The mean scores of the perivenous artifacts and the reflux of contrast material were significantly higher in patients with left arm injection than in those with right arm injection. The perivenous artifacts and reflux of contrast material were more prominent in patients with central venous stenosis (maximum stenosis area <50mm(2)) than those without stenosis. CONCLUSIONS: The image degradation in CT of the neck, due to perivenous artifacts and venous reflux, can be reduced with the right arm injection of contrast material when compared with the left arm injection.

Accuracy of CT angiography in the assessment of the circle of Willis: comparison of volume-rendered images and digital subtraction angiography.

BACKGROUND: Computed tomography angiography (CTA) is increasingly used for non-invasive imaging of the cerebrovascular diseases. PURPOSE: To evaluate the accuracy of CTA in the assessment of the variation of the segment calibers of the circle of Willis. MATERIAL AND METHODS: One hundred and 17 patients with acute SAH (51 men and 66 women, mean age 50.9 years) who underwent CTA using a 16 detector-row CT scanner and DSA were evaluated retrospectively. The CTA and DSA studies were performed within 24 h after the onset of symptoms and within 24 h of each other. A total of 819 arterial segments (A-comA, right and left A1 segment, right and left P-com A, and right and left P1 segment) of the circle of Willis were determined to be aplastic (grade 1), hypoplastic (grade 2), or normal-sized (grade 3) by blinded observers evaluating CTA volume-rendered images. The CTA results were then compared with findings on the corresponding DSA images (reference standard). RESULTS: The overall agreement between CTA and DSA was 92.4%. We had 62 (7.6%) cases of disagreement (58 cases of under-estimation and four cases of over-estimation by CTA) between tow modalities. The sensitivity and specificity of CTA in the detection of aplastic and normal-sized segments were more than 90%. In contrast, subgroup analysis of the hypoplastic segments showed a sensitivity of 52.6% and a specificity of 98.2%. CONCLUSION: CTA is highly accurate in the assessment of anatomical variations of the circle of Willis; however, its sensitivity is limited in depicting hypoplastic segments.