Articles
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747 results found
Article
≤11 ribs (differential)
≤11 ribs is associated with a number of congenital abnormalities and skeletal dysplasias, including:
Down syndrome (trisomy 21)
campomelic dysplasia
kyphomelic dysplasias
asphyxiating thoracic dysplasia (Jeune syndrome)
short rib polydactyly syndromes
trisomy 18
chromosome 1q21.1 deletion...
Article
Abnormally thickened endometrium (differential)
Abnormally thickened endometrium on imaging may occur for a number of reasons which may be categorized based on whether or not they are related to pregnancy. Etiologies may also be classified based on whether the patient is premenopausal or postmenopausal.
Differential diagnosis
Pregnancy-rela...
Article
Abnormal testicular Doppler flow (differential)
Abnormal testicular Doppler flow (arterial, venous, or both) can be a differential challenge. Always remember that the patient's presenting history helps quite a bit in narrowing the differential.
Reduced flow
partial testicular torsion (<360 degrees)
venous outflow is obstructed first, resul...
Article
Absent fetal stomach on ultrasound (differential)
Non-visualization of the fetal stomach on ultrasound can occur with various physiological as well as pathological processes. It becomes a significant sonographic observation >14 weeks of gestation (about the time the fetus begins to swallow).
Causes include:
physiological emptying: transient
...
Article
Achilles tendon thickening
Achilles tendon thickening can occur for a number of reasons. The Achilles tendon has an average AP diameter of 6 mm 1. Thickening of the tendon is when it exceeds 8 mm in AP diameter and can result from:
Achilles tendinosis/tear
post-surgical thickening
retrocalcaneal bursitis
degeneration
...
Article
Acro-osteolysis
Acro-osteolysis (plural: acro-osteolyses), also known as phalangeal osteolysis, refers to resorption of the distal phalanx. The terminal tuft is most commonly affected. It is associated with a heterogeneous group of pathological entities, some of which can be remembered by the mnemonic CHOP FIN...
Article
Acute airspace opacification with lymphadenopathy (differential)
Acute airspace opacification with lymphadenopathy is a subset of the differential diagnosis for generalized airspace opacification and includes:
post-obstructive causes (usually chronic, but 'new' changes can occur)
primary lung cancer
pulmonary metastases
lymphoma/leukemia
infection
prim...
Article
Acute bilateral airspace opacification (differential)
Acute bilateral airspace opacification is a subset of the larger differential diagnosis for airspace opacification. An exhaustive list of all possible causes of acute bilateral airspace opacities is long, but a useful way to consider the huge list is via the material within the airways:
infecti...
Article
Acute unilateral airspace opacification (differential)
Acute unilateral airspace opacification is a subset of the differential diagnosis for airspace opacification.
Differential diagnosis
The exhaustive list of all possible causes would be huge, but a useful framework includes:
pus (i.e. pulmonary infection)
bacterial pneumonia
fungal pneumon...
Article
Adrenal calcification
Adrenal calcification is not a rare finding in healthy asymptomatic people and is usually the result of previous hemorrhage or tuberculosis. Addison disease patients only occasionally develop calcification.
Pathology
Etiology
Hemorrhage
sepsis: Waterhouse-Friderichsen syndrome
blunt abdomi...
Article
Adult cervical lymphadenopathy (differential)
Cervical lymphadenopathy in an adult can result from a vast number of conditions. They include:
malignancy
metastases
from head and neck tumors
lymphoma
other neoplastic lesions
Castleman disease
Kaposi sarcoma
infection
bacterial infection
viral infection
Epstein-Barr virus
herpes ...
Article
Air space opacities
The differential for air space opacities is extensive, and needs to be interpreted in context of chronicity (previous imaging) and clinical context. It is therefore useful to divide airspace opacities as follows:
acute airspace opacities with lymph node enlargement
acute airspace opacities: un...
Article
Altered breast density between two mammograms
Mammographic screening detects early breast cancers and thereby reduces potential mortality. However, its sensitivity is inversely related to breast density 1.
Altered density between two mammograms can arise in a number of situations:
Affecting both breasts:
interval commencement/cessation ...
Article
Alternating radiolucent and radiodense metaphyseal lines
Alternating radiolucent and radiodense metaphyseal lines can be seen with a number of conditions and the differential diagnosis is wide:
growth arrest lines
bisphosphonate therapy
rickets: especially those on prolonged treatment, e.g. vitamin D dependent rickets
osteopetrosis
chemotherapy
...
Article
Amorphous calcifications (breast)
Amorphous calcifications, previously known as indistinct calcifications, are a morphological descriptor for breast calcifications that are small and/or hazy such that no clearly defined shape/form can be ascribed.
Pathology
Many benign and malignant conditions may be seen in association with ...
Article
Anterior knee pain
Anterior knee pain is common with a variety of causes which can be divided anatomically using a layered approach1 from superficial to deep:
Superficial soft tissues
prepatellar bursitis
Morel-Lavallée lesion
infrapatellar bursitis
Extensor mechanism
quadriceps tendinosis / partial tear
q...
Article
Anterior mediastinal mass
Anterior mediastinal masses can be caused by neoplastic and non-neoplastic pathology. These masses arise in the anterior mediastinum, that portion of the mediastinum anterior to the pericardium and below the level of the clavicles.
Epidemiology
The prevalence of anterior mediastinal masses on...
Article
Anterior vertebral body beaking
Anterior vertebral body beaking occurs in a number of conditions and may emanate from the central portion or the lower third of the vertebral body.
Middle third
Morquio syndrome 1 (middle for Morquio)
Lower third
Hurler syndrome 2
achondroplasia 3
congenital hypothyroidism (formerly, creti...
Article
Apical cap
Apical caps cover the lung apices and often bilateral. They can be chronic, due to fibrosis or acute due to pleural or extra-pleural fluid.
Epidemiology
The frequency of chronic apical pleural thickening increases with age 3. There may be a slightly greater male predilection 7.
Pathology
Api...
Article
Apical chest mass
Apical chest masses are often important and may be missed, especially when examined with a plain chest radiograph. It is always recommended to perform a targeted assessment of the apices of the lungs during a chest x-ray; they are one of the classic review areas.
Pathology
Etiology
Commonly a...
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