Bilateral persistence of type 1 proatlantal arteries: report of a case and review of the literature.
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Persistent proatlantal artery type 1 is one of the four anastomotic vessels between the carotid and vertebrobasilar arterial systems. Persistence of this embryonic anastomosis is extremely rare. We present such a case with bilateral persistent proatlantal arteries that arose from internal carotid arteries, entered the skull via the foramen magnum and united with the horizontal portions of vertebral arteries. We also mention its embryology, potential clinical implications, and differentiating features between two types of proatlantal arteries. (+info)
Persistent carotid-vertebrobasilar anastomoses: how and why differentiating them?
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The persistent carotid-vertebrobasilar anastomoses (PCVBA) can be explained by an interruption of the vertebrobasilar system (VBS) embryogenesis. We present two very rare cases of persistent anastomoses: a hypoglossal artery and a type I proatlantal artery, insisting on the angiographic criteria allowing differentiation. After a brief review of the embryogenesis of the VBS, we describe the different types of persistent anastomoses (hypoglossal, type I and II proatlantal, trigeminal and otic arteries). We will insist on the potential risks, not well-known, but typical of each anastomosis. PCVBA usually are incidental findings but imaging follow-up may be required since aneurysms may develop. (+info)
Atlas: standard diagnostic tests for an unusual fracture.
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The case is reported of an unusual atlas fracture with no reports of such an injury in the literature. The diagnosis of this injury emphasises the importance of simple clinical decision instruments, and systematic interpretation of investigations. (+info)
JAtlasView: a Java atlas-viewer for browsing biomedical 3D images and atlases.
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BACKGROUND: Many three-dimensional (3D) images are routinely collected in biomedical research and a number of digital atlases with associated anatomical and other information have been published. A number of tools are available for viewing this data ranging from commercial visualization packages to freely available, typically system architecture dependent, solutions. Here we discuss an atlas viewer implemented to run on any workstation using the architecture neutral Java programming language. RESULTS: We report the development of a freely available Java based viewer for 3D image data, descibe the structure and functionality of the viewer and how automated tools can be developed to manage the Java Native Interface code. The viewer allows arbitrary re-sectioning of the data and interactive browsing through the volume. With appropriately formatted data, for example as provided for the Electronic Atlas of the Developing Human Brain, a 3D surface view and anatomical browsing is available. The interface is developed in Java with Java3D providing the 3D rendering. For efficiency the image data is manipulated using the Woolz image-processing library provided as a dynamically linked module for each machine architecture. CONCLUSION: We conclude that Java provides an appropriate environment for efficient development of these tools and techniques exist to allow computationally efficient image-processing libraries to be integrated relatively easily. (+info)
Aplasia of the posterior arc of the atlas with persistent posterior tubercle: a case report.
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An unusual case of partial aplasia of the posterior arc of the atlas, with persistent posterior tubercle, is presented in a previously healthy individual who sustained a neck trauma. Both plain X-rays and CT findings specified the lesion. Dynamic X-rays in flexion and extension showed an immobile posterior tubercle. The patient did not develop neurological symptoms at any stage during follow-up (1 year). (+info)
Providing visualisation support for the analysis of anatomy ontology data.
(22/126)
BACKGROUND: Improvements in technology have been accompanied by the generation of large amounts of complex data. This same technology must be harnessed effectively if the knowledge stored within the data is to be retrieved. Storing data in ontologies aids its management; ontologies serve as controlled vocabularies that promote data exchange and re-use, improving analysis. The Edinburgh Mouse Atlas Project stores the developmental stages of the mouse embryo in anatomy ontologies. This project is looking at the use of visual data overviews for intuitive analysis of the ontology data. RESULTS: A prototype has been developed that visualises the ontologies using directed acyclic graphs in two dimensions, with the ability to study detail in regions of interest in isolation or within the context of the overview. This is followed by the development of a technique that layers individual anatomy ontologies in three-dimensional space, so that relationships across multiple data sets may be mapped using physical links drawn along the third axis. CONCLUSION: Usability evaluations of the applications confirmed advantages in visual analysis of complex data. This project will look next at data input from multiple sources, and continue to develop the techniques presented to provide intuitive identification of relationships that span multiple ontologies. (+info)
Coincidental deficiency of the posterior arch of the atlas and thalassaemia minor: possible pitfalls in a trauma victim.
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Congenital abnormalities of the cervical spine are rare findings in trauma victims. Deficiency of the posterior arch of the atlas and coincidental thalassaemia minor are even more unusual. This case report is about a young female trauma victim with both abnormalities, a combination that has previously not been described in literature. The classification, as proposed by Currarino et al in 1994, and the importance of being aware of these abnormalities are discussed. (+info)
Os odontoideum with bipartite atlas and segmental instability: a case report.
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We report on the case of a 15-year-old adolescent who presented with a transient paraplegia and hyposensibility of the upper extremities after sustaining a minor hyperflexion trauma to the cervical spine. Neuroimaging studies revealed atlantoaxial dislocation and ventral compression of the rostral spinal cord with increased cord signal at C1/C2 levels caused by an os odontoideum, as well as anterior and posterior arch defects of the atlas. The patient underwent closed reduction and posterior atlantoaxial fusion. We describe the association of an acquired instability secondary to an os odontoideum with an anteroposterior spondyloschisis of the atlas and its functional result after 12 months. The rare coincidence of both lesions indicates a multiple malformation of the upper cervical spine and supports the theory of an embryologic genesis of os odontoideum. (+info)