Articles
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More than 200 results
Article
Assessment of thyroid lesions (general)
Assessment of thyroid lesions is commonly encountered in radiological practice.
Thyroid mass
hyperplastic/colloid nodule/nodular hyperplasia: 85%
adenoma
follicular: 5%
others: rare
primary thyroid cancer (carcinoma)
papillary: 60-80% of carcinomas
follicular: 10-20%
medullary: 5%
anap...
Article
Positron emission tomography
Positron emission tomography (PET) is a modern non-invasive imaging technique for quantification of radioactivity in vivo. It involves the intravenous injection of a positron-emitting radiopharmaceutical, waiting to allow for systemic distribution, and then scanning for detection and quantificat...
Article
Primary bone lymphoma
Primary bone (skeletal/osseous) lymphoma (PBL) is a less common manifestation of lymphoma than secondary involvement from disseminated lymphoma. It is rare, accounting for <5% of bone tumors and <1% of non-Hodgkin lymphoma.
Terminology
PBL is defined as the presence of lymphoma isolated to one...
Article
Immunosuppression
Immunosuppression is the impairment of the body's immune system which can alter the ability of the body's defense mechanisms to prevent diseases, particularly certain infections, including opportunistic infections, and cancers.
Terminology
Patients with immunosuppression are said to be immuno...
Article
Leptomeningeal enhancement
Leptomeningeal enhancement refers to a diffuse or focal gyriform or serpentine enhancement that can be seen in the following conditions:
Diffuse
meningitis
pyogenic meningitis
viral meningitis
tuberculous meningitis (can also be focal)
CNS cryptococcal infection
coccidioidal meningitis (c...
Article
Astroblastoma, MN1-altered
Astroblastomas are rare glial tumors usually found in the cerebral hemispheres of young adults and children.
Terminology
The exact nature of astroblastomas remains to be fully elucidated. Tumors with compatible histological features have a variety of molecular characteristics and overlap with...
Article
Intramedullary spinal tumors
Intramedullary spinal tumors are rare, representing 4-10% of all CNS tumors and <10% of all pediatric CNS neoplasms 5. They account for 20% of all intraspinal tumors in adults and 35% of all intraspinal tumors in children 8.
A long duration of symptoms prior to diagnosis is typical.
Pathology
...
Article
RECIST 1.1: comparison with RECIST 1.0
Response Evaluation Criteria In Solid Tumors (RECIST) was updated to version 1.1 in 2009.
For both RECIST 1.0 and 1.1, the requirement for measurable disease at baseline depends on the endpoints of the clinical trial.
The fundamental concept common to both versions of RECIST is that measurable...
Article
Complications of radiation therapy
Radiation therapy has the potential to cause complications in many organ systems, many of which, especially in the thorax, are important for radiologists to be aware of.
acute radiation syndrome
complications of cranial radiation therapy
radiation-induced cerebral vasculopathy
radiation-ind...
Article
Parotid gland enlargement
Parotid gland enlargement (also known as parotidomegaly) has a wide differential given the significant breadth of pathology that can affect the parotid gland. These can be separated by a standard surgical sieve approach into infective, inflammatory, immune, neoplastic, infiltrative, and congenit...
Article
Alveolar soft part sarcoma
Alveolar soft part sarcoma (ASPS) is a rare, highly vascular, deep soft tissue mesenchymal malignancy that is classically seen in the lower extremities of young adults. They account for <1% of all soft tissue sarcomas.
Epidemiology
There is a slight female predilection in patients less than 30...
Article
Dysplastic cerebellar gangliocytoma
Dysplastic cerebellar gangliocytoma, perhaps better known as Lhermitte-Duclos disease, is a rare tumor of the cerebellum appearing as thickening and increase in T2 signal of the cerebellar folia giving this lesion a characteristic striated appearance.
Epidemiology
Dysplastic cerebellar gangli...
Article
Liposclerosing myxofibrous tumor
Liposclerosing myxofibrous tumors (LSMFT), also known as polymorphic fibro-osseous lesions of bone, are rare benign fibro-osseous lesions that have a predilection for the intertrochanteric region of the femur.
The histopathological origin of this lesion is unclear and under discussion 1-3.
Ter...
Article
Bone metastases
Bone (skeletal) metastases are the third most frequent behind lung and liver metastases 6. They result in significant morbidity in patients with metastatic disease. Although the diagnosis is often straightforward, especially as in many cases there is a well-documented history of metastatic malig...
Article
Protoplasmic astrocytoma (historical)
Protoplasmic astrocytoma is a historical term previously applied to an uncommon variant of diffuse adult-type astrocytomas.
Terminology
The term was removed in the updated 4th edition (2016) of the WHO classification of CNS tumors, with these tumors folded into what is now referred to as astro...
Article
Inferior vena caval thrombosis
Inferior vena caval thrombosis is an essential diagnosis while evaluating any neoplastic lesion, or portal hypertension. It is also important to differentiate bland thrombus from tumor thrombus.
Clinical features
A patient can present with many features which include
bilateral pedal edema
Bu...
Article
Immune checkpoint inhibitor therapy related pneumonitis
Immune checkpoint inhibitor therapy-related pneumonitis is one of the complications that can occur in the setting of immune checkpoint inhibitor therapy.
Epidemiology
Immune checkpoint inhibitor therapy-related pneumonitis is considered a rare complication with a reported incidence of <5% in m...
Article
Mediastinal lymph node enlargement
Mediastinal lymph node enlargement can occur from a wide range of pathologies and can be isolated or associated with lung pathology. Historically, a size cut-off of 10 mm short-axis diameter was used.
Terminology
The term mediastinal lymphadenopathy implies lymph node disease and is not synon...
Article
Pure ground glass nodules
Pure ground glass lung nodules (pGGN's) are a subtype of ground glass lung nodules where there is no associated solid component.
Pathology
Etiology
Apart from inflammatory foci they have been shown to represent various pathologies such as 1,3
adenocarcinoma in situ of lung
minimally-invasiv...
Article
Masaoka staging system of thymoma
The Masaoka staging system is commonly adopted for thymomas 1-3, and is the most important determinant of survival following surgical resection 4:
stage I: intact thymic capsule
stage II: capsular invasion into adjacent mediastinal fat or pleura
stage III: macroscopic invasion into adjacent o...