Articles

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16,800 results found
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AO Spine classification of upper cervical injuries

The AO Spine classification of upper cervical injuries is a concise and comprehensive system for categorizing the spectrum of traumatic bony and ligamentous injuries involving the occipital condyles, atlas (C1), or axis (C2). Usage The AO Spine upper cervical classification system is relativel...
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Broncho-arterial ratio

The broncho-arterial (BA) ratio is a descriptive parameter used in thoracic CT imaging. It is defined as the diameter of the bronchial lumen divided by the diameter of its accompanying artery 1. It is usually measured in the segmental to subsegmental artery level. Usually the measurement is made...
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Normal facial nerve enhancement on MRI

The normal facial nerve (CN VII) can demonstrate some enhancement post gadolinium, with the prevalence of which segments is highly variable depending on the MRI sequence 4-8. Enhancement may be asymmetric 4-6. It has been attributed to the circumneural facial arteriovenous plexus.c Typical site...
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Stahl classification of Kienböck disease (historical)

The Ståhl classification of Kienböck disease was one of the first staging systems of Kienböck disease (osteonecrosis of the lunate). It has been modified by Lichtman et al and is considered outdated for clinical practice. Classification This system divides the disease into five stages, and i...
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Undifferentiated embryonal sarcoma of the liver

Undifferentiated embryonal sarcomas of the liver are rare, aggressive, and malignant liver tumors encountered in the pediatric population.  Epidemiology Approximately 90% of cases occur in patients under 15 years of age, most commonly between 6 and 10 years of age, but some cases have been rep...
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Annular pancreas

Annular pancreas is a morphological anomaly that results in pancreatic tissue completely or incompletely encircling the duodenum. This condition can cause duodenal obstruction and is therefore important to recognize, as radiologists are frequently the first to make the diagnosis. Epidemiology ...
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AO/OTA classification of proximal humeral fractures

The Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association (AO/OTA) classification together with the Neer classification is one of the most frequently used systems for classifying proximal humeral fractures. Like fractures in other bone segments, proximal humeral fractures are...
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AO/OTA classification of malleolar fractures

The AO/OTA classification of malleolar segment fractures is one of the most frequently used systems for classifying malleolar fractures. It takes the Danis-Weber classification into account and can be correlated to the Lauge-Hansen classification. Malleolar fractures are divided into three grou...
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AO/OTA classification of distal tibial fractures

The AO/OTA classification is one of the most frequently used systems for classifying distal tibial fractures or tibial distal end segment fractures. Like other fractures, they are divided into three groups subject to the severity and complexity of the respective injury 1, 2: type A: extraarticu...
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AO Spine classification of thoracolumbar injuries

The AO Spine classification of thoracolumbar injuries is a commonly used thoracolumbar spinal fracture classification system 1,2. The current AO Spine system (2013) supercedes the more complex and less reproducible AO Magerl classification 3. Unlike the other widely used system, the thoracolumb...
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AO Spine classification of subaxial injuries

The AO Spine classification of subaxial injuries aims to simplify and universalise the classification of subaxial cervical spine fractures and improve interobserver and intraobserver reliability. Usage Although its existence is widely known among the relevant subspecialty groups, its day-to-da...
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AO Spine classification of sacral injuries

The AO Spine classification of sacral injuries aims to simplify and universalise the process of classifying sacral injuries and improve interobserver and intraobserver reliability. The AO Spine sacral classification is broken into three subsections that follow a hierarchical structure similar t...
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AO classification of clavicle fractures

The AO classification of clavicular fractures along with the Neer classification system is one of the more frequently used classification systems when assessing distal clavicular fractures. Classification The classification system, broken into three categories focuses on the displacement and p...
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AO classification of distal femur fractures

The AO classification of distal femoral fractures is one of the commonly used fracture classification systems in orthopedics. Each long bone has a single number with the parts of the bone denoted numerically, the proximal end is 1, diaphysis is 2, and the distal end is 3.  The distal femur sys...
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AO Spine classification systems

The AO Spine classification systems is a group of imaging morphology-based classification system, combined with clinical factors for injury of spinal trauma. It is designed to be a simple and reproducible method of describing injury patterns 1, 2, 3. AO Spine has published four injury classific...
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Medial medullary syndrome

Medial medullary syndrome, also known as Déjerine syndrome,  is secondary to thrombotic or embolic occlusion of small perforating branches from vertebral or proximal basilar artery supplying the medial aspect of medulla oblongata1,2. Epidemiology Represents less than 1% of brainstem stroke syn...
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Pyogenic meningitis

Pyogenic meningitis, also referred as bacterial meningitis, is a life-threatening CNS infectious disease affecting the meninges, with elevated mortality and disability rates. Three bacteria (Haemophilus influenzae, Streptococcus pneumoniae, Neisseria meningitidis) account for the majority of cas...
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Sonographic halo sign (disambiguation)

Sonographic halo sign can be useful in a number of situations: hypoechoic halo sign (also known as target or bull's eye sign) in liver metastases: used in hepatobiliary imaging, is a concerning feature for malignant lesion if the lesion is a hyperechoic liver lesion 1,2 ultrasound halo in angi...
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Calcific tendinitis

Calcific tendinitis, also known as calcific tendinopathy or tendonitis, is a self-limiting condition due to the deposition of calcium hydroxyapatite within tendons, usually of the rotator cuff. It is a common presentation of hydroxyapatite crystal deposition disease (HADD).  Epidemiology Typic...
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Spontaneous intracranial hypotension

Intracranial hypotension, also known as craniospinal hypotension is a clinical entity that results from a cerebrospinal fluid (CSF) leak that almost without exception occurs from the spine, either into the epidural space or directly into veins in the setting of CSF-venous fistulas. It usually, b...

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