Articles
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More than 200 results
Article
Using and attributing images from Radiopaedia
Using images from Radiopaedia in your presentations is not only OK but is actively encouraged. Radiopaedia is all about sharing our knowledge and cases and by so doing, makes it easier to teach and to learn from each other.
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Article
Foster Kennedy syndrome
Foster Kennedy syndrome describes the clinical syndrome of unilateral optic atrophy with contralateral papilledema caused by an ipsilateral compressive mass lesion.
Clinical presentation
The syndrome consists of two cardinal features, in relation to a mass lesion 1,2:
ipsilateral optic nerve ...
Article
Mesothelioma
Mesothelioma is an aggressive malignant tumor of mesothelium and 90% of tumors arise from the pleura.
This article is about the pleural form of the disease, other locations include 17:
peritoneal mesothelioma (~10%)
pericardial mesothelioma (<1%)
cystic/multicystic mesothelioma
tunica vagi...
Article
Otsu's method
Otsu’s method, also known as Otsu's threshold algorithm, is an automatic thresholding algorithm used in image processing.
The method separates pixels or voxels from an image into groups based on where their values lie in relation to the image histogram. The method finds threshold values that c...
Article
Cerebral hyperperfusion syndrome
Cerebral hyperperfusion syndrome is a rare complication seen after treatment of long-standing severe carotid stenosis by carotid endarterectomy or carotid artery stenting. It is believed to be the result of failure of normal cerebral blood flow autoregulation.
Terminology
Cerebral hyperperfus...
Article
Hereditary elliptocytosis
Hereditary elliptocytosis, also known as hereditary ovalocytosis, is a condition which results from varying genetic mutations that lead to the formation of abnormally shaped red blood cells that are ovoid. It may cause a hemolytic anemia.
Epidemiology
There are various geographic trends for t...
Article
Myokymia
Myokymia refers to an involuntary undulating movement of muscle 1.
The term is employed in a number of clinical contexts 1-5:
eyelid myokymia: pathogenesis is not well understood
extra-ocular muscle myokymia: pathogenesis is not well understood
inferior oblique myokymia (rare)
superior obli...
Article
Infantile hepatic hemangioma
Infantile hepatic hemangiomas (IHH) are liver lesions composed of large endothelial-lined vascular channels seen in fetuses and neonates. They are not to be confused with hepatic epithelioid hemangioendothelioma, which occurs in older patients.
Terminology
These benign tumors were previously r...
Article
Posterior dynamic lumbar stabilization
Posterior dynamic lumbar stabilization is an alternative instrumented method to rigid spinal fusion aiming to improve segmental stability. Purported advantages of this technique include reduced posterior element and intervertebral disc loading reducing symptoms and potentially allowing for disc ...
Article
External petrosal nerve
The external petrosal nerve is one of the three branches from the geniculate ganglion. It carries sympathetic fibers from the sympathetic plexus surrounding the middle meningeal artery, coursing extradurally laterally to the greater and lesser petrosal nerves on the petrous ridge's anterior surf...
Article
Aceruloplasminemia
Aceruloplasminemia is an autosomal recessive type of neurodegeneration with brain iron accumulation and disorder of iron metabolism caused by a mutation in the ceruloplasmin (CP) gene resulting in the production of dysfunctional ceruloplasmin.
Epidemiology
Aceruloplasminemia is a very rare dis...
Article
Cerebral cortical T2 hyperintensity
Cerebral cortical T2 hyperintensity or gyriform T2 hyperintensity refers to curvilinear hyperintense signal involving the cerebral cortex on T2 weighted and FLAIR imaging.
The causes include:
developmental anomalies
focal cortical dysplasia
neoplastic
glioblastoma 1
vascular thrombo-occlus...
Article
Patient confidentiality
Patient confidentiality and anonymity are of paramount importance.
Under no circumstances should any information, whether in the patient's presenting symptoms, case description, or images themselves, be uploaded that could identify an individual patient.
In short, nothing in your images or ac...
Article
Fetal MRI
Fetal MRI allows for detailed imaging of the developing fetus in utero. Fast sequences are required due to fetal movement 1. Fetal MRI is most commonly utilized when ultrasound findings are equivocal. Fetal anatomy can be evaluated in detail including the brain, upper aerodigestive tract, thorax...
Article
Rosenbach sign (aortic valve regurgitation)
Rosenbach sign is a clinical sign that is seen in severe aortic/tricuspid valve regurgitation. It is elicited as pulsation of the liver, during systole, and it is primarily due to the increased cardiac output and associated retrograde blood flow into the liver 1-3.
See also
Rosenbach also gave...
Article
Obturator sign
Obturator sign is a clinical sign of acute appendicitis, it is defined as discomfort felt by the subject/patient on the slow internal movement of the hip joint, while the right knee is flexed. It indicates an inflamed pelvic appendix that is in contact with the obturator internus muscle 1-3.
Se...
Article
Perineural spread of tumor
Perineural spread of tumor is a form of local invasion in which primary tumors cells spread along the tissues of the nerve sheath. It is a well-recognized phenomenon in head and neck cancers.
Terminology
An important distinction has to be made between perineural invasion (PNI) and perineural ...
Article
Interspinous device
Implantation of interspinous devices is one option for treating lumbar canal stenosis and other causes of low back pain. These devices attempt to produce lumbar flexion by distracting the lumbar spinous processes restoring height and resulting in tightening of the thickened ligamentum flavum, an...
Article
Boas sign
Boas sign is a clinical sign that is defined as hyperesthesia felt by the patient to light touch in the right lower scapular region or the right upper quadrant of the abdomen. It is classically seen in patients with acute cholecystitis.
History and etymology
Ismar Isidor Boas (1858–1938), was ...
Article
Nucleic acids
The nucleic acids are the collective term for the two main macromolecular nucleotide polymers:
DNA (deoxyribonucleic acid)
RNA (ribonucleic acid)
Nucleotides, the constituent units of nucleic acids, are made up of simpler molecules called nucleosides and inorganic phosphate (H3PO4). Each nucl...
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