Articles
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16,882 results found
Article
Critical angle (ultrasound)
The critical angle (θc) describes a refractive phenomenon in ultrasonography, whereby a specific incident angle of the sound beam will result in 'total reflection' 1. In this situation, the transmitted sound beam, will run parallel to the boundary of the second tissue without penetrating it 1. T...
Article
Bottom of sulcus focal cortical dysplasia
Bottom of sulcus focal cortical dysplasia, or simply bottom of sulcus dysplasia, refers to a highly epileptogenic and localized focal cortical dysplasia that is anatomically restricted to, and maximal at, the bottom of a cortical sulcus.
Clinical presentation
The typical clinical presentation ...
Article
Osteomyelitis pubis
Osteomyelitis pubis refers to infectious inflammation of the symphysis pubis.
Epidemiology
It may account for accounts for 2% of hematogenous osteomyelitis and accounts for less than 1% of all bone infections.
Pathology
It can occur either secondarily to hematogenous bacterial implantation o...
Article
Bronchial triangle sign
The bronchial triangle sign is a CT feature that has been proposed to aid differentiation of a pulmonary hamartoma from a peripheral pulmonary carcinoid. It may be present in both, but is thought be more frequent in the latter (i.e. peripheral pulmonary carcinoids) and may seen as triangular-sha...
Article
Mitral aortic intervalvular fibrosa
The mitral-aortic intervalvular fibrosa (MAIVF) refers to a thin, fibrous, membranous avascular region located between the anterior leaflet of the mitral valve (left atrioventricular orifice) and non-coronary cusp of the aortic valve in the heart.
It extends from the right fibrous trigone to th...
Article
Pseudoaneurysm of the mitral aortic intervalvular fibrosa
Pseudoaneurysm of the mitral aortic intervalvular fibrosa (p-MAIVF) refers to a pseudoaneurysm in the region of the avascular fibrous tissue between the mitral and aortic valves (i.e. the mitral-aortic intervalvular fibrosa (MAIVF)).
Pathology
Etiology
They may rarely occur as a result of inf...
Article
Stent graft–induced new entry tear
A stent graft–induced new entry (SINE) tear refers to a new tear within an existing dissection flap caused by a stent graft placement. It excludes those arising from natural disease progression or iatrogenic injury from the endovascular manipulation. It is a potential complication from a thoraci...
Article
Sagittal vertical axis
Sagittal vertical axis/alignment (SVA) is one of the simplest and most widely used methods to assess sagittal balance 1-3.
Measurement
This measurement is performed on lateral standing full-length spine x-rays. A plumb line is drawn vertically from the middle of the C7 vertebral body 1,2 or th...
Article
Spinopelvic balance
Spinopelvic balance is an important concept in adult spinal deformities. There are numerous ways of assessing spinopelvic balance, using various bony landmarks and angles to evaluate whether or not a normal distribution of weight and stresses is present through the axial skeleton, some incorpora...
Article
Hemiplegic migraine
Hemiplegic migraines are an uncommon type of migraine with aura wherein patients present with usually reversible motor weakness, typically unilateral. They can be challenging to distinguish from seizure with Todd paresis or ischemic stroke, even with the benefit of MRI 1.
Epidemiology
Compared...
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
Limited intimal tear
Limited intimal tears (LIT) of the aorta or limited aortic intimal tears are subtle localized tears of the aortic intima without tear extension and represent an uncommon form of aortic dissection that can manifest as acute aortic syndrome 1-5.
Epidemiology
Limited intimal tears are uncommon an...
Article
Left hemicolectomy
Left hemicolectomy is a surgical procedure in which splenic flexure, descending colon, and a portion of the sigmoid colon are removed for radical treatment of various pathologies affecting the descending colon.
Indications
colon cancer
inflammatory bowel disease
isolated left diverticular di...
Article
Mastectomy
Mastectomy is a surgical treatment for breast cancer in which the entire breast tissue is removed through a surgical procedure as opposed to a wide local excision. Sometimes, adjacent structures, such as lymph nodes, are removed to prevent recurrence or metastasis. In some cases, mastectomy is d...
Article
Decompressive craniectomy
Decompressive craniectomies are craniectomies performed to relieve raised intracranial pressure, most commonly in the setting of florid cerebral edema following cranial trauma or swelling following infarction 1.
History
Craniectomies for the treatment of cranial trauma date back to at least 10...
Article
Knee arthroplasty (overview)
Knee arthroplasty is a common joint replacement procedure employed in the management of various pathologic conditions of the knee joint, most commonly osteoarthritis. Less common indications include inflammatory arthritis and following trauma 1.
Multiple types of knee arthroplasty have been dev...
Article
5-ALA fluorescence-guided surgery
5-ALA fluorescence-guided surgery is an intraoperative technique that takes advantage of tumor cells accumulating a fluorescent compound to make the location of the tumor more readily apparent. It is primarily used in the resection of high-grade gliomas (e.g. glioblastoma, grade 3 or 4 astrocyto...
Article
Aortoesophageal fistula
Aortoesophageal (aorto-esophageal) fistulae are pathologic communications between the aorta and esophagus and result in life-threatening upper gastrointestinal hemorrhage. They are fatal in the absence of prompt management.
Epidemiology
Aortoesophageal fistulas are a rare entity that accounts...
Article
Nuclear medicine training in Australia
Nuclear medicine training in Australia can be undertaken as part of or after radiology training through the Royal Australian and New Zealand College of Radiologists (RANZCR) or following basic physician training (BPT) through the Royal Australasian College of Physicians (RACP).
Structure
Entry...
Article
METhodological RadiomICs Score (METRICS)
The METhodological RadiomICs Score (METRICS) is a 30-item quality evaluation tool for artificial intelligence (AI) and radiomics papers 1. It aims to assess and improve the quality of radiomics research. METRICS is endorsed by the European Society of Medical Imaging Informatics (EuSoMII).
Overv...