How actual motor competence and perceived motor competence influence motor‐skill engagement of a novel cycling task

In early childhood, factors that contribute to motor‐skill engagement (MSE) are unknown. Our aim was to explore the relationships between actual and perceived motor competence and their influences on MSE on a balance bike (bike with no pedals). A secondary aim was to investigate whether MSE had an effect on ability on a balance bike. This study comprised of 45 children (29% female) aged 4.5 ± 0.5 years. MSE was assessed using distance travelled on a balance bike over an 8‐week period. Actual motor competence was assessed using the Movement Assessment Battery for Children, second edition. Perceived motor competence was assessed using the Pictorial Scale of Perceived Movement Skill Competence. Ability on a balance bike was measured using timed trials on a specifically designed track. Pearson product‐moment correlations were used to assess relationships between actual and perceived motor competence and ability on a balance bike. Linear regressions were used to examine whether actual or perceived motor competence or ability on a balance bike predicted MSE. Repeated measures ANOVA was used to examine whether there was a difference in ability on a balance bike between three MSE groups over 8 weeks. No relationships were found, and none of the variables predicted MSE. There was a significant difference between the MSE groups on ability on a balance bike over time (P = 0.019). Investigating the contributors to MSE on a novel cycling task during early childhood provides knowledge to ensure children are given the best opportunities for practice and acquisition of skills.     

Segmentation of cardiac cine-MR images and myocardial deformation assessment using level set methods

In this paper, we present an original method to assess the deformations of the left ventricular myocardium on cardiac cine-MRI. First, a segmentation process, based on a level set method is directly applied on a 2D+t dataset to detect endocardial contours. Second, the successive segmented contours are matched using a procedure of global alignment, followed by a morphing process based on a level set approach. Finally, local measurements of myocardial deformations are derived from the previously determined matched contours. The validation step is realized by comparing our results to the measurements achieved on the same patients by an expert using the semi-automated HARP reference method on tagged MR images.     

Color vision and fatigue: an incidental finding

INTRODUCTION: Because there is little information available as to how fatigue and color vision interact, we present some incidental findings on how a protanope and a color-normal perform on several color vision tests after 1 night of sleep deprivation. CASE REPORT: A series of clinically and occupationally based color vision tests were administered to a protanope and a color-normal subject after they had stayed awake all night and after a regular night's sleep. There was essentially no change in their performance on the clinical color vision tests; however, both did worse on the occupationally based color vision tests after 1 night of sleep deprivation. The color-normal made numerous errors in identifying colors displayed on a video display terminal, whereas the protanope had a large increase in errors on the CN Lantern Test. Both subjects passed these respective tests after a regular night's sleep. CONCLUSIONS: The primary reason for color-normal's poor performance on the video display terminal test was probably due to a decrement in his visuo-motor control rather than a loss in color discrimination. In contrast, the protanope's poor performance on the lantern test was probably due to the additive effects of the inherent limitations of his visual system and fatigue.     

福定碱对胆碱酯酶的抑制特点

福定碱是一新结构类型的可逆性胆碱酯酶抑制剂。它具有较强的拟胆碱作用。对小鼠脑、红细胞和猪脑固相胆碱酯酶(AChE)的抑制强度为对血浆胆碱酯酶(BuChE)抑制强度的数千倍。体内对小鼠AChE的抑制时间远比氨基甲酸酯类化合物催醒宁(二甲氨基甲酸-5-(1,3,3-三甲基)吲哚满酯盐酸盐(TIDC)长。抑酶方式属竞争和非竞争性的混合型抑制。     

Solitary Necrotic Nodules of the Liver Mimicking Hepatic Metastasis: Report of Two Cases

We present two cases of solitary necrotic nodules of the liver which on radiologic images mimicked hepatic metastasis. Solitary necrotic nodule of the liver is a rare but benign entity which histopathologically consists of an outer fibrotic capsule with inflammatory cells and a central core of amorphous necrotic material. The lesion was seen on contrast-enhanced CT as an ovoid-shaped hypoattenuating nodule; on CT during hepatic arteriography as enhancing nodule; on intraoperative US as a target-appearing hypoechoic nodule; on T2WI as a hyperintensity nodule, and on dynamic MR as a subtle peripheral enhancing nodule. Although the radiologic features are not specific, solitary necrotic nodule of the liver should be included in the differential diagnosis of hepatic metastasis.     

Multimodality imaging of fat-containing adrenal metastasis from hepatocellular carcinoma

A biopsy-proven fat-containing metastasis to the adrenal gland in a patient with hepatocellular carcinoma demonstrated low density on nonenhanced CT, heterogeneity on contrast-enhanced CT, and marked signal loss on opposed-phase gradient-echo MRI, mimicking an adrenal adenoma. However, the mass was not present on older studies and showed increased FDG uptake on PET. The possibility of a fat-containing metastasis should be considered for an apparent adrenal adenoma in a patient with a primary hepatocellular carcinoma.     

Influence of rib structure on detection of subtle lung nodules

PURPOSE: To access the influence of anatomic noise on the detectability of subtle lung nodules depicted on chest radiographs. MATERIAL AND METHODS: From normal chest radiography images, 132 square regions were extracted, of which the centers were on the upper margin of a rib, the inside of a rib, the lower margin of a rib, and the central region between two adjoining ribs. Simulated nodules were digitally superimposed at the centers of these extracted square images. Twelve radiologists viewed 50 soft-copy images consisting of these 792 processed images, including the noise-added images. The observer's confidence level for the square images containing single nodules was used as an index of observer performance. RESULTS: Results indicated statistically reliable effects of the relationship between rib structures and nodule positions on the detection performance (P < 0.001). The nodule detectability on the images with a center located between two adjoining ribs was significantly the best, whereas it was significantly the worst on the noise-added images with a center located between two adjoining ribs. CONCLUSION: The rib structures overlying a subtle lung nodule on chest X-ray images have a detrimental effect on nodule detection performance as anatomic noise, regardless of the nodule location on ribs.     

Role of sonography in evaluation of radial scars of the breast

OBJECTIVE: We investigated the usefulness of sonography in revealing radial scars suspected on mammography. CONCLUSION: Many radial scars are visible on sonography and, when visible, may present features virtually identical to those of carcinoma of the breast. Findings indicative of a radial scar are often more conspicuous on sonography than on mammography; thus, sonography may have a definitive role when evaluating subtle findings suggestive of a radial scar or when features of a radial scar are evident on only one mammographic view and cannot be localized with certainty.     

Giant cell reparative granuloma of the temporal bone: MR findings with pathologic correlation

We report MR findings in a case of a giant cell reparative granuloma involving the temporal lobe in a middle-aged man. On MR images, most of the mass was hypointense on T1-weighted images, hypointense on T2-weighted images, and mildly enhanced on postcontrast T1-weighted images. The hypointensity on T2-weighted images corresponded to areas of hemorrhage and hemosiderin deposition on pathologic correlation.     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Magnetic resonance imaging in pediatric elbow fractures

Purpose: Magnetic resonance imaging (MRI) evaluation of pediatric elbow trauma with or without a visible fracture on radiography.

Material and Methods: MRI was performed in the acute phase in 25 children with an elbow injury. Nine patients with an elbow effusion only on radiographs and 16 with a fracture or luxation seen on radiographs underwent subsequent MRI. No sedation was used.

Results: MRI revealed eight occult fractures (89%) in seven out of nine patients who had only an effusion on radiographs. Based on MRI findings, septic arthritis was suspected in one patient. Two patients out of five with a supracondylar fracture on the radiograph had a cartilage lesion in the humerus. MRI depicted a 3-mm gap on the articular surface in two patients with a lateral condyle fracture, a more accurate fracture location in two patients than the radiographs, and an additional occult fracture in two patients. MRI showed a fracture not seen on radiographs in two of three patients with prior luxation.

Conclusion: MRI is a sensitive and accurate method in the diagnosis of pediatric elbow injuries, especially when only an effusion is present on radiographs. Occult fractures are more common in pediatric patients with elbow injury than reported earlier.     

Electromagnetic interventions in musculoskeletal disorders

Electromagnetic interventions in general and those considering the musculoskeletal system in particular hold many obscurities. Several studies revealing positive effects of electromagnetic fields oppose those showing no beneficial effects. After a historical review and a discussion of basic details on electromagnetic signals, this article provides information on the effects of electromagnetic fields on a cellular level and gives an account of preclinical and clinical studies focused on electromagnetic interventions by means of weak pulsed electromagnetic fields on musculoskeletal disorders.     

The value of narrow CT window settings in the recognition of subtle acute aortic intramural haematoma

Four patients with acute aortic intramural haematoma are presented. In all patients the typical crescentic hyperdense rim within the aortic wall was not obvious on unenhanced CT when reviewed on standard mediastinal windows, but the hyperdense crescentic rim was well seen on narrow window settings. The findings suggest that all patients with a typical clinical presentation of acute thoracic aortic dissection who do not have a classical dissection on contrast-enhanced CT or a hyperdense intramural haematoma on standard mediastinal settings, should have the non-contrast scans reviewed on narrow window settings.     

Redistributed Regional Ventilation after the Administration of a Bronchodilator Demonstrated on Xenon-Inhaled Dual-Energy CT in a Patient with Asthma

We report here on the redistributed regional ventilation abnormalities after the administration of a bronchodilator and as seen on xenon-inhaled dual-energy CT in a patient with asthma. The improved ventilation seen in the right lower lobe and the decreased ventilation seen in the right middle lobe after the administration of a bronchodilator on xenon-inhaled dual-energy CT could explain a positive bronchodilator response on a pulmonary function test. These changes may reflect the heterogeneity of the airway responsiveness to a bronchodilator in patients with asthma.     

Multirater agreement of arthroscopic meniscal lesions

BACKGROUND: Establishing the validity of classification schemes is a crucial preparatory step that should precede multicenter studies. There are no studies investigating the reproducibility of arthroscopic classification of meniscal pathology among multiple surgeons at different institutions. HYPOTHESIS: Arthroscopic classification of meniscal pathology is reliable and reproducible and suitable for multicenter studies that involve multiple surgeons. STUDY DESIGN: Multirater agreement study. METHODS: Seven surgeons reviewed a video of 18 meniscal tears and completed a meniscal classification questionnaire. Multirater agreement was calculated based on the proportion of agreement, the kappa coefficient, and the intraclass correlation coefficient. RESULTS: There was a 46% agreement on the central/peripheral location of tears (kappa = 0.30), an 80% agreement on the depth of tears (kappa = 0.46), a 72% agreement on the presence of a degenerative component (kappa = 0.44), a 71% agreement on whether lateral tears were central to the popliteal hiatus (kappa = 0.42), a 73% agreement on the type of tear (kappa = 0.63), an 87% agreement on the location of the tear (kappa = 0.61), and an 84% agreement on the treatment of tears (kappa = 0.66). There was considerable agreement among surgeons on length, with an intraclass correlation coefficient of 0.78, 95% confidence interval of 0.57 to 0.92, and P < .001. CONCLUSIONS: Arthroscopic grading of meniscal pathology is reliable and reproducible. CLINICAL RELEVANCE: Surgeons can reliably classify meniscal pathology and agree on treatment, which is important for multicenter trials.     

Intracranial Fibroxanthoma in an Infant: a Case Report

A primary fibroxanthoma of the central nervous system is very rare. We present a case of an infantile fibroxanthoma that arose from the cranial dura mater in a six-month-old girl with US, MRI and PET/CT features that mimicked a meningioma. The tumor appeared as a large, well-circumscribed echogenic mass in the right parieto-occipital area on US. The tumor was seen as isoattenuated to slightly hypoattenuated on pre-contrast CT scan and as hypometabolic on PET/CT. As seen on T2-weighted image, the mass was heterogeneously hyperintense to the gray matter. The mass was isointense on T1-weighted image and homogeneously strongly enhanced on contrast enhanced T1-weighted image.     

Image construction methods for phased array magnetic resonance imaging

PURPOSE: To study image construction in phased array magnetic resonance imaging (MRI) systems from a statistical signal processing point of view. MATERIALS AND METHODS: Three new approaches for image combination with multiple coils are proposed: 1) one based on the singular value decomposition of the measurement matrix, which is asymptotically optimal in the signal-to-noise ratio sense; 2) one based on a maximum-likelihood formulation, incorporating a priori information on the coil sensitivities in a Bayesian manner; and 3) one based on a least-squares formulation, which incorporates a smoothness constraint on the coil sensitivities. RESULTS: Numerical examples using synthetic and real data are presented to illustrate the performance of these new approaches. Results on the synthetic data show improvement in signal-to-error ratio, while results on the real data (a 4.7 T four-coil image of a cat spinal cord) show that the proposed methods can improve the SNR in the final image by up to 3 dB in the regions of interest compared to conventional sum-of-squares processing. CONCLUSION: It is demonstrated that phased array MRI reconstruction performance can be improved by the use of more elaborate statistical signal processing algorithms.     

Adenomatoid odontogenic tumor: correlation of MRI with histopathological findings

Adenomatoid odontogenic tumor is a rare benign and odontogenic tumor that is frequently misdiagnosed as other odontogenic cysts and tumors on radiographic examination. To acquire additional information of adenomatoid odontogenic tumor, we performed magnetic resonance imagings (MRI) at a case of adenomatoid odontogenic tumor. The lesion was divided between the peripheral portion with a thick circular shape and the central portion with a round shape on the basis of the signal intensity (SI) of MRI. The peripheral portion showed intermediate SI contained multifocal no SI on T1WI, high SI contained multifocal no SI on T2WI, and heterogeneous enhancement on CE-T1WI. These multifocal areas corresponded to the numerous punctate radiopaque foci shown on computed tomography. The central portion showed homogeneous low SI on T1WI, homogeneous very high SI on T2WI, and no enhancement on CE-T1WI. Macroscopic examination revealed the round shaped lesion included one large cystic space correspondent to the central portion with a clear cystic wall correspondent to the peripheral portion on MRI. The MRI features corresponded to the macroscopic findings of the histopathological examination.     

Congenital hepatic artery aneurysm simulating pancreatic carcinoma

The authors report a case of a hepatic artery aneurysm that simulated a mass in the head of the pancreas. The correct diagnosis was made preoperatively based on several findings: curvilinear calcification within the mass on CT, a well-defined cystic collection on ultrasound, absence of biliary duct dilatation or jaundice, and presence of other aneurysms.     

Comparison of the panoramic radiographic and CT features of post-Caldwell-Luc maxillary sinuses

OBJECTIVE: To clarify the panoramic radiographic features of the post-Caldwell-Luc maxillary sinus. METHODS: The panoramic radiographs were compared with the axial CT scans of 48 symptomatic post-Caldwell-Luc maxillary sinuses which had been operated on more than 5 years previously. RESULTS: The two characteristic features of the post-Caldwell-Luc maxillary sinus on panoramic radiographs were a right-angled triangular shape, due to absence of the floor of the maxillary sinus and radiopacity of the posterior wall and zygomatic bone, and an ill-defied panoramic innominate line. This shape was related to the finding of a contracted sinus with a radiolucent lumen on the CT scans. There was also close relationship between the ill-defined panoramic innominate line and thickened posterior wall on the CT scans. CONCLUSION: The characteristic features of the post-Caldwell-Luc maxillary sinus on panoramic radiographs were a right-angled triangular shape and an ill-defined panoramic innominate line. These features were related to a contracted sinus and a thickened posterior wall on the CT scans.