Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.
782 results found
Article
Resorptive (obstructive) atelectasis
Resorptive or obstructive atelectasis is a form of lung collapse that is due to obstruction of the airways supplying a lung segment or lobe. It is a term used to distinguish atelectasis identified on imaging based on the underlying pathophysiology to guide diagnosis.
Clinical presentation
The ...
Article
Restrictive cardiomyopathy
Restrictive cardiomyopathy is the least common subtype of cardiomyopathy and is characterized by a marked decrease in ventricular compliance.
Clinical presentation
Patients can present with symptoms and signs of left ventricular failure and/or right ventricular failure 9.
Pathology
It is p...
Article
Retained gallstone
Retained gallstones, also called dropped or slipped gallstones, are common during a laparoscopic cholecystectomy, with a reported incidence of 0.1–20%, and occur when gallstones are inadvertently spilled into the peritoneal cavity.
Clinical presentation
Many cases of dropped gallstones will be...
Article
Retrorectal developmental cysts
Retrorectal developmental cysts are rare and mostly congenital benign lesions found in the retrorectal space:
spectrum of cystic teratomas
retrorectal epidermoid cyst
retrorectal dermoid cyst
retrorectal teratoid cyst
enteric cysts
duplication cyst of the rectum
tailgut duplication cyst
...
Article
Reverse bat wing pulmonary opacities
Reverse bat wing pulmonary opacities refer to peripheral opacities of the lungs, sparing the perihilar region. It is a relatively unusual appearance with a fairly narrow differential:
chronic eosinophilic pneumonia
organizing pneumonia (formerly bronchiolitis obliterans with organizing pneumon...
Article
Rhizomelic dwarfism
Rhizomelic dwarfism is a type of dwarfism where the dominant feature is proximal (i.e. femoral, humeral) limb shortening.
Pathology
The following conditions fall under the heading of rhizomelic dwarfism 3
metatropic dysplasia
achondrogenesis
rhizomelic chondrodysplasia punctata
achondropla...
Article
Rib notching
Rib notching refers to deformation of the superior or inferior surface of the rib. It can affect a single rib (from trauma or solitary masses e.g. schwannoma) or can affect multiple ribs.
Differential diagnosis
The differentials differ according to whether it is the superior or inferior surfac...
Article
Right atrial enlargement
Right atrial (RA) enlargement is less common, and harder to delineate on chest radiograph, than left atrial (LA) enlargement.
Pathology
Etiology
Enlargement of the right atrium (RA) can result from a number of conditions, including:
raised right ventricular pressures
pulmonary arterial hype...
Article
Right iliac fossa mass (differential)
Right iliac fossa mass is a common clinical presentation and has a range of differentials that need to be excluded. Radiology plays an important role in this differentiation.
Differential diagnosis
appendicular mass
appendicular abscess
appendicular mucocele
appendicular neoplasms
ileoceca...
Article
Right lower lobe collapse
A right lower lobe (RLL) collapse has distinctive features, and is usually relatively easily identified. The absence of overlying cardiomediastinal outline makes it easier to appreciate than left lower lobe collapse.
Findings of lower lobe collapse can be grouped together as they are almost id...
Article
Right lower lobe consolidation
Right lower lobe consolidation refers to consolidation in part (incomplete) or all (complete) of the right lower lobe.
Pathology
Consolidation refers to the alveolar airspaces being filled with fluid (exudate/transudate/blood), cells (inflammatory), tissue, or other material.
The list of caus...
Article
Right middle lobe collapse
Right middle lobe collapse (or simply termed middle lobe collapse) has distinctive features, but can be subtle on frontal chest radiographs.
For a general discussion please refer to the article on lobar collapse.
It is important to note that of all the lobes, the right middle lobe is the mo...
Article
Right middle lobe consolidation
Right middle lobe consolidation refers to consolidation in part (incomplete) or all (complete) of the right middle lobe.
Pathology
Consolidation refers to the alveolar airspaces being filled with fluid (exudate/transudate/blood), cells (inflammatory), tissue, or other material.
The list of ca...
Article
Right upper lobe collapse
Right upper lobe collapse has distinctive features, and is usually easily identified on frontal chest radiographs; much more so than left upper lobe collapse.
For a general discussion please refer to the article on lobar collapse.
Radiographic features
Chest radiograph
Collapse of the right ...
Article
Right upper lobe consolidation
Right upper lobe consolidation refers to consolidation in part (incomplete) or all (complete) of the right upper lobe.
Pathology
Consolidation refers to the alveolar airspaces being filled with fluid (exudate/transudate/blood), cells (inflammatory), tissue, or other material.
The list of caus...
Article
Risk factors for testicular germ cell tumors
Risk factors for testicular germ cell tumors (GCT) include:
Caucasians at higher risk than African Americans (9:1)
undescended testis
10-40x increased risk
around 10% of all tumors are associated with undescended testis
higher risk if intra-abdominal testis compared with intra-inguinal
or...
Article
Round atelectasis
Round atelectasis, also known as rounded atelectasis, folded lung or Blesovsky syndrome, is an unusual type of lung atelectasis where there is infolding of a redundant pleura. The way the lung collapses can at times give a false mass-like appearance.
Pathology
Two theories have been put forwar...
Article
Sacral lesions
A very wide range of lesions can occur in and around the sacrum.
Tumors
primary sacral tumors
malignant
sacral chordoma: most common primary sacral tumor 1
chondrosarcoma
Ewing sarcoma / pPNET
osteosarcoma: often arises from Paget disease in this location
multiple myeloma/plasmacytoma
...
Article
Sacroiliitis (differential)
Sacroiliitis (inflammation of the sacroiliac joint) can be a manifestation of a wide range of disease processes. The pattern of involvement is helpful for narrowing down the differential diagnosis.
Usually bilateral and symmetrical
enteropathic arthritis
Crohn disease
ulcerative colitis
a...
Article
Salivary gland tumors
Salivary gland tumors are variable in location, origin, and malignant potential.
Pathology
In general, the ratio of benign to malignant tumors is proportional to the gland size; i.e. the parotid gland tends to have benign neoplasms, the submandibular gland 50:50, and the sublingual glands and...
Article
Sausage digit
The term sausage digit refers to the clinical and radiologic appearance of diffuse fusiform swelling of a digit due to soft-tissue inflammation from underlying arthritis or dactylitis.
Pathology
The common causes of sausage digit are
psoriatic arthropathy
osteomyelitis
sickle cell anemia
...
Article
Scalp hematoma
A scalp hematoma usually occurs following an injury at delivery although they are commonly seen with head trauma.
Classification
There are three types of hematoma, which are defined by their location within the scalp, particular their location as related to the galea aponeurosis and skull peri...
Article
Scapholunate angle
The scapholunate angle is the angle between the long axis of the scaphoid and the mid axis of the lunate on the sagittal imaging of the wrist. In a normal situation, it should be between 30 and 60o in the resting (neutral) position.
The scapholunate angle is abnormal in carpal instability:
inc...
Article
Scapular fracture
Scapula fractures are uncommon injuries, representing ~3% of all shoulder fractures.
Pathology
Mechanisms of injury
requires high energy trauma (e.g. motor vehicle accidents account for 50% of scapular fractures)
direct trauma to the shoulder region
indirect trauma through falling on outstr...
Article
Scham sign (hip)
The Scham sign of slipped capital femoral epiphysis is one of the subtle signs that may be seen on the AP view of an adolescent hip with early slip.
In the normal adolescent hip, an intraarticular portion of the diaphysis of the collum overlies the posterior wall of the acetabulum inferiomedial...
Article
Scheuermann disease
Scheuermann disease, also known as juvenile kyphosis, juvenile discogenic disease 11, or vertebral epiphysitis, is a common condition which results in kyphosis of the thoracic or thoracolumbar spine. The diagnosis is usually made on plain film.
Epidemiology
occurs in ~5% (range 0.4-8%) of the ...
Article
SCIWORA
SCIWORA is the abbreviation of spinal cord injury without radiographic abnormality 1,2. This can be an indication for MRI when there is a persisting, objective myelopathy after a traumatic event with normal plain film and CT findings. It accounts for ~10% of spinal cord injuries.
Epidemiology
...
Article
Sclerosing bone dysplasias
Sclerosing bone dysplasias comprise a heterogeneous group of disorders (skeletal dysplasias) united by the presence of sclerosis of one form or another. Some of these entities are thought to be related (e.g. osteopoikilosis, melorheostosis and Buschke-Ollendorff syndrome) 1.
They include:
cra...
Article
Sclerosing cholangitis
There are three forms of sclerosing cholangitis:
primary sclerosing cholangitis
IgG4-related sclerosing cholangitis
secondary sclerosing cholangitis
Article
Sclerotic bone metastases
Sclerotic or blastic bone metastases can arise from a number of different primary malignancies including 1-4:
prostate carcinoma (most common)
breast carcinoma (may be mixed)
transitional cell carcinoma (TCC)
carcinoid
medulloblastoma
neuroblastoma
mucinous adenocarcinoma of the gastroint...
Article
Sclerotic clavicle
Sclerotic clavicles have many causes:
trauma: fractured clavicle
arthritis: osteoarthritis, seronegative arthritides
osteitis condensans of the clavicle 1
SAPHO syndrome
clavicular tumors
metastases
osteosarcoma
lymphoma
osteoblastoma
bone island
tumor-like lesions
eosinophilic granu...
Article
Scrotal infections
The scrotum and its content are subject to a number of infective processes including:
scrotal cellulitis
scrotal abscess
Fournier gangrene
epididymitis
epididymo-orchitis
orchitis
testicular abscess
scrotal filariasis
Article
Scrotal tunica cyst
Scrotal tunica cysts are paratesticular cystic lesions. They include:
tunica vaginalis cysts
tunica albuginea cysts
Radiographic features
Ultrasound
Typically seen as a simple appearing paratesticular cystic lesion not in the region of the epididymis.
See also
paratesticular lesions
Article
Secondary organizing pneumonia
Secondary organizing pneumonia (SOP) refers to organizing pneumonia that can be attributed to a specific cause, in contrast to cryptogenic organizing pneumonia (COP) in which no cause is present.
Pathology
Etiology
SOP can be attributed to the following causes 1:
Prior infection
bacteria
...
Article
Segmental atelectasis
Segmental atelectasis refers to collapse of one or several segments of a lung lobe. It is a morphological subtype of lung atelectasis. It is better appreciated on CT and Its radiographic appearance can range from being a thin linear to a wedge shaped opacity then does not abut an interlobar fiss...
Article
Sensorineural hearing loss
Sensorineural hearing loss (SNHL) refers to deafness secondary to conditions affecting the inner ear, internal acoustic canal, cerebellopontine angle, or vestibulocochlear nerve.
Pathology
Conditions that cause sensorineural hearing loss can be divided by location:
inner ear
bony labyrinth
...
Article
Seronegative spondyloarthritis
Seronegative spondyloarthritides, also known as spondyloarthropathies (SpA), are a group of musculoskeletal syndromes linked by common clinical features and immunopathologic mechanisms. The subtypes of spondyloarthritis are usually distinguished on the basis of history and clinical findings.
Te...
Article
Shaggy heart border
The shaggy heart border is a descriptive term referring to the ill definition of the cardiac silhouette on a chest radiograph. Due to its imprecise nature, some caution is advised against its use in radiological reports 4.
It usually implies pleural disease on the mediastinal interface 3 and ma...
Article
Shifting granuloma sign
Shifting granuloma sign refers to a shift in the location of a parenchymal lesion visible on prior films that may be seen in the presence of atelectasis.
For example, this occurs when a calcified granuloma is present in a lung and a significant parenchymal collapse "shifts" it from one location...
Article
Shortened fetal femoral length
Shorted fetal femur is a morphological descriptor and is usually defined when the femoral length falls below the 5th centile for gestational age (some define it when it is under the 2.5th centile 5) or less than 0.91 predicted by the bi-parietal diameter. It can occur in isolated or in associati...
Article
Shortened fetal humerus
Shortened fetal humerus is a morphological description and is usually defined when the humeral length falls below the 5th percentile or less than 0.9 as predicted by the biparietal diameter (BPD). It can occur in isolation or in association with a number of other anomalies.
The humeral length i...
Article
Shortening of the fourth/fifth metacarpals/metatarsals
Shortening of the fourth/fifth metacarpals and less commonly metatarsals is seen in a variety of apparently disparate conditions.
Pathology
Etiology
Common causes 2:
idiopathic
post-infective (e.g. osteomyelitis, yaws, tuberculosis dactylitis)
pseudohypoparathyroidism/pseudopseudohypopara...
Article
Short limb skeletal dysplasia
Short limb skeletal dysplasias are skeletal dysplasias which are characterized by limb shortening
Classification
Rhizomelic (proximal limb shortening)
hypochondroplasia
achondroplasia
chondrodysplasia punctata
pseudoachondroplasia
thanatophoric dysplasia
particularly type II
kyphomelic...
Article
Short stem hip arthroplasty
Short stem hip arthroplasties are a special type of hip joint replacement where as the name states the stem is shorter than usual. It is known by various trade names including the NANOS system. In selected patients it is thought to result in fewer complication rates 1.
Article
Short umbilical cord
Short umbilical cord has been variably defined. Considering the mean length of the umbilical cord is 50-70 cm 1-2, a short cord in absolute terms is usually taken as one that is under 35-40 cm in length at term 1-2.
Pathology
Associations
Recognized associations include
chromosomal anomalie...
Article
Simultanagnosia
Simultanagnosia is the inability of one to perceive more than one object at a time. It is a characteristic symptom of Bálint syndrome and can also be seen with posterior cortical atrophy (PCA).
Article
Sincipital encephalocele
Sincipital encephaloceles are congenital herniations of cerebral parenchyma through a cranial defect. There are three main types 1,2:
frontonasal encephalocele (~50%): more common in Asia and Latin America 4
naso-ethmoidal encephalocele (30%): more common in North America 4
naso-orbital (naso...
Article
Single layer periosteal reaction
Single layer (or lamellar) periosteal reaction is a uniformly dense, single thin layer of new bone about 1-2 mm from the cortical surface. It usually denotes a acute or subacute pathological process. Passive hyperemia causes increased osteoblastic activity and production of new bone.
Pathology
...
Article
Single pleural based mass (differential)
The differential for a single pleural mass is essentially the same as that for multiple pleural masses with the addition of a few entities.
tumors
pleural tumors
solitary fibrous tumor of the pleura (pleural fibroma)
mesothelioma
localized mediastinal malignant mesothelioma
metastatic pl...
Article
Sinonasal disease
The nasal passage and paranasal sinuses (collectively sinonasal) plays host to a number of diseases and conditions, which can be collectively termed sinonasal disease. One way of classifying separate entities is as follows:
inflammatory and infective conditions
sinusitis
acute sinusitis
Pott...
Article
Sister Mary Joseph nodule
A Sister Mary Joseph nodule is a metastatic lesion involving the umbilicus. The most common primary source is an intra-abdominal adenocarcinoma.
Epidemiology
Umbilical metastases are uncommon, reportedly present in 1-3% of all intra-abdominal and/or pelvic malignancy 7.
Clinical presentation
...
Article
Skeletal dysplasia
Skeletal dysplasia (also known as osteochondrodysplasia) refers to any abnormality in bone formation. There is a very wide clinicopathological spectrum and any part of the skeleton can be affected.
Epidemiology
The overall prevalence is estimated at ~2 per 10,000 live births 3.
Pathology
Typ...
Article
Skeletal lesions with giant cells
There are a number of skeletal lesions with giant cells on histology, which may occasionally lead to mischaracterization of the lesion.
Below is a list of lesions with giant cells as an important histological feature, to aid in differential diagnosis if the histological diagnosis of a lesion do...
Article
Skeletal metastasis
Skeletal metastases (a.k.a. bone metastases) are common and 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 malignancy, sometimes they may mimic beni...
Article
Skeletal muscle edema on MRI (differential)
The presence of intramuscular edema (increased high T2/STIR signal) on MRI carries an extremely broad differential. They include:
trauma
effects of direct injury or tear
denervation injury: denervation changes in muscles
early myositis ossificans
inflammatory myopathies
dermatomyositis
po...
Article
Skin thickening on mammography (differential)
The presence of skin thickening on mammography is variably defined, usually being more than 2 mm in thickness. It can result from a number of both benign and malignant causes. They include:
Malignant
inflammatory breast cancer: one of the most concerning causes of skin thickening: this usually...
Article
Skull base angle
The skull base angle allows the diagnosis of platybasia and basilar kyphosis. There are several different techniques that may be used on sagittal images from MRI or CT.
Traditionally, basal angle measurements were based on plain skull images. With the advent and generalization of MR imaging it ...
Article
Skull tumors
Skull tumors can be (as with tumors anywhere else) both primary and secondary, and benign or malignant.
Primary
Benign
osteoma
ossifying fibroma
osteoblastoma
hemangioma
giant cell tumor (GCT)
aneurysmal bone cyst (ABC)
epidermoid and dermoid cysts
chondroma
Malignant
osteosarcoma
c...
Article
Small bowel folds (differential)
Regular, smooth generalized thickening
edema
congestive cardiac failure (CCF)
hypoalbuminemia
lymphatic obstruction
angioneurotic edema
infection
radiation
ischemia
hemorrhage
anticoagulation or bleeding diathesis
vasculitides
IgA vasculitis (Henoch-Schonlein purpura)
Buerger diseas...
Article
Small bowel imaging
Small bowel imaging aims at assessment of the disorders of small intestine.
Imaging techniques
barium follow through
fluoroscopic enteroclysis
conventional CT
CT enteroclysis
MR enteroclysis
CT enterography
MR enterography
capsule endoscopy
Article
Small bowel ischemia
Small bowel ischemia may be a life-threatening condition, arising from any one of numerous causes of disturbance of the normal blood flow through the small bowel wall.
Pathology
It can be divided into acute and chronic forms, with the main underlying etiologies (each discussed separately) bei...
Article
Small for date fetus
A small for dates fetus can result from a number of factors
Fetal factors
aneuploidy
trisomy
triploidy
skeletal dysplasia(s)
structural anomalies (syndromes)
Maternal factors
Common
hypertension
medication(s):
fetal Warfarin syndrome
hydantoin embryopathy (Dilantin TM)
cytotoxic dru...
Article
Small lung volume (differential diagnosis)
The following differential diagnoses can be considered when small lung volumes are seen:
pulmonary fibrosis
prior surgery, e.g. lobectomy, lung volume reduction surgery
pleural disease, e.g. pleural thickening
skeletal deformities, e.g. kyphosis, scoliosis
systemic lupus erythematosus (SLE)...
Article
Small placenta
A small placenta if observed on antenatal ultrasound can arise from a number of situations. They include:
variation in placental morphology: where only part of the placenta is seen
bilobed placenta: with only one lobe seen
succenturiate lobe: with either main lobe or succenturiate lobe not se...
Article
Smoking related lung disease
Smoking related lung diseases are the respiratory manifestations of disease that are related to the smoking of tobacco. Smoking affects the lungs in numerous ways, and can be classified under the following headings:
smoking related-interstitial lung diseases (SR-ILD)
respiratory bronchiolitis ...
Article
Snake eyes (facial nerve)
Snake eyes, also known as snail eyes, is a term used to refer to the appearance of the facial nerve on coronal CT within its canal in the petrous temporal bone as the tympanic segment doubles back next to the labyrinthine segment. Anteriorly, these two segments converge at the geniculate ganglio...
Article
Soft tissue calcification
Soft tissue calcification is commonly seen and caused by a wide range of pathology.
Differential diagnosis
There is a wide range of causes of soft tissue calcification 1:
dystrophic soft tissue calcification (most common)
chronic venous insufficiency 2
vascular
arterial calcification
phle...
Article
Soft tissue lesions with predominately low T1 and T2 signal (differential)
Soft tissue lesions with predominately low T1 and T2 signal have a reasonably long differential, including:
Common
air
densely calcified/ossified lesions
foreign body
gout
flow voids
arteriovenous fistula
aneurysm
post-operative changes
hematoma, chronic
plantar fibromatosis
pigmen...
Article
Soft-tissue sarcoma
Soft-tissue sarcomas are a heterogeneous group of malignant tumors of mesenchymal origin (sarcoma) that originate from the soft tissues rather than bone. They are classified on the basis of tissue seen on histology. The commoner sarcomas in the adult and pediatric population are listed below.
A...
Article
Solid and enhancing pituitary region mass
Solid lesions with enhancement are by far the most commonly encountered appearance of pituitary region masses.
Differential diagnosis
macroadenoma
by far the most common entity
typically enhances less vividly than other entities
elevates the dura of the diaphragma sella (as the origin is wi...
Article
Solid periosteal reaction
Solid periosteal pattern is thought to evolve from single layer and multilayered periosteal reactions, forming a solid layer of mature new bone adjacent to the cortex. It denotes a longstanding pathological process.
Pathology
It has been associated with:
osteoid osteoma
osteomyelitis
osteos...
Article
Solitary filling defect of the ureter (differential)
Solitary filling defect with a ureter, as seen on conventional IVU or CT IVU has some differentials, including:
within the lumen
calculus
sloughed papilla
blood clot
benign polyp
within the wall
transitional cell carcinoma (TCC)
tuberculosis
metastasis
endometriosis
When multiple fi...
Article
Solitary ill-defined osteolytic lesion (differential)
Ill-defined solitary osteolytic lesions can be caused by following entities 1:
intraosseous hemangioma
chondroblastoma
osteoblastoma
giant cell tumor
fibrosarcoma of bone
malignant fibrous histiocytoma
chondrosarcoma
osteosarcoma
Ewing's sarcoma
angiosarcoma
multiple myeloma
intraoss...
Article
Solitary lucent skull lesion
Solitary lucent lesion of the skull is a relatively frequent finding. The differential is heavily influenced by the patient's age.
Older adult/elderly
metastasis/malignancy
breast cancer
lung cancer
melanoma
thyroid cancer
renal cell cancer
multiple myeloma
epidermoid and dermoid
hema...
Article
Solitary pulmonary nodules
Solitary pulmonary nodule (SPN) is defined as a relatively well defined round or oval pulmonary parenchymal lesion equal to or smaller than 30 mm in diameter. It is surrounded by pulmonary parenchyma and/or visceral pleura and is not associated with lymphadenopathy, atelectasis, or pneumonia 9.
...
Article
Solitary sclerotic bone lesion
The differential diagnosis of a solitary sclerotic bone lesion is heavily influenced by the age of the patient, and includes:
sclerotic metastasis
solitary either because no others are present or no others have been imaged
enostosis (bone island)
osteosarcoma
calcifying enchondroma
osteobl...
Article
Solitary sclerotic bone lesion with a lucent center
Solitary sclerotic bone lesion with a lucent center have a number of differentials:
neoplastic
osteoid osteoma
osteoblastoma
infective
Brodie abscess
tuberculosis
syphilis
yaws
Article
Solitary well defined osteolytic lesion (differential)
Well defined solitary osteolytic lesions can be seen with following conditions 1-2:
subchondral geodes or cysts
intraosseous ganglion
intraosseous tophus (gout)
unicameral bone cyst
aneurysmal bone cyst
glomus tumor
enchondroma
epidermoid inclusion cyst
chondroblastoma
non-ossifying fi...
Article
Somatostatinoma
Somatostatinomas are a rare type of neuroendocrine tumor. They may represent around 1% of all gastro-entero-pancreatic endocrine neoplasms.
Clinical presentation
The presentation can be variable. Patients with functional somatostatinoma may present with an "inhibitory syndrome" which is a tria...
Article
Sonographic values in obstetrics and gynecology
Obstetric and gynecological ultrasound is rampant with numerous cut off values. Some of these get revised over the years. The following list is a useful aid to refer to and revise.
1 mm
rate of increase of a mean sac diameter per day in early pregnancy
2 mm
generally accepted value for a thi...
Article
Speckled anterior horn of lateral meniscus
The speckled appearance of the anterior horn of lateral meniscus is a feature that can be seen as a normal variant on MRI scans. It is usually seen near its central attachment site. It is often explained by fibers of the anterior cruciate ligament and the covering synovium inserting into the men...
Article
Spiculated periosteal reaction
Spiculated periosteal reaction represents spicules of new bone forming along vascular channels and the fibrous bands that anchor tendons to bone (Sharpey fibers). A spiculated periosteal reaction signifies a rapid underlying process that prevents formation of new bone under the raised periosteum...
Article
Spinal cord compression
Spinal cord compression is a surgical emergency, usually requiring prompt surgical decompression to prevent permanent neurological impairment. If the spinal roots below the conus medullaris are involved, it is termed cauda equina syndrome.
Pathology
Etiology
There are numerous causes of cord ...
Article
Spinal dysraphism
Spinal dysraphisms refer to a broad group of malformations affecting the spine and/or surrounding structures in the dorsum of the embryo. They are a form of neural tube defect.
Pathology
The neural tube is formed by the lengthwise closure of the neural plate, in the dorsum of the embryo.
The ...
Article
Spinal epidural cystic lesions (differential)
Spinal epidural cystic lesions are fluid-filled lesions within the spinal canal but outside the thecal sac. Their clinical significance is as a potential contributor to spinal cord or nerve root impingement. The differential diagnosis for spinal epidural cysts consists of several entities that d...
Article
Spinal epidural mass
The differential diagnosis for a spinal epidural mass includes:
epidural metastasis
epidural abscess
herniated nucleus pulposus
epidural hematoma
epidural arteriovenous malformation
epidural angiolipoma
epidural lipomatosis
Article
Spinal fractures
Spinal fractures are usually the result of significant trauma to a normally formed skeleton or the result of trauma to a weakened spinal column. Examples include:
Jefferson fracture: ring fracture of C1
hangman fracture: bilateral pedicle or pars fracture of C2
dens fracture
flexion teardrop...
Article
Spinal hematoma
Spinal hematomas are a rare clinical entity and are often idiopathic. Prompt diagnosis and treatment are crucial, lest they cause permanent neurological damage.
Identifying the location of the hematoma is important for treatment, as is distinguishing it, to the extent possible, from other entit...
Article
Spinal metastases
Spinal metastases is a vague term which can be variably taken to refer to metastatic disease to any of the following:
vertebral metastases (94%)
may have epidural extension
intradural extramedullary metastases (5%)
intramedullary metastases (1%)
Each of these are discussed separately. Below...
Article
Spinal vascular malformations
Spinal vascular malformations (SVM) are rare but knowledge of them is important as if undiagnosed and untreated they can lead to serious complications.
Pathology
There are two main types of SVMs 1,2:
spinal arteriovenous fistula (AVF): 70% of SVMs
pial: small, large, or giant
dural AVF (DA...
Article
Splenic abscess
Splenic abscesses, like abscesses elsewhere, are localized collections of necrotic inflammatory tissue caused by bacterial, parasitic or fungal agents. They uncommonly affect the spleen due to its efficient reticuloendothelial system phagocytic activity and, consequently, are more likely seen in...
Article
Splenic amyloidosis
Splenic amyloidosis is rare as an isolated entity. Most often it is associated with either systemic amyloidosis or hepatic amyloidosis.
Epidemiology
In general, splenic involvement in amyloidosis is rather frequent (5-10% of cases 6,7).
Clinical presentation
Symptoms include abdominal mass a...
Article
Splenic calcification
Splenic calcifications can occur is various shapes and forms and can occur from a myriad of etiological factors.
The usual calcification observed in radiographs are the multiple, miliary form presenting numerous small rounded densities averaging from three to five millimeters in diameter where ...