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.
639 results found
Article
Prader-Willi syndrome
Prader-Willi syndrome is a rare genetic disorder. It is the most common cause of obesity caused by a genetic syndrome.
Clinical presentation
Prader-Willi syndrome is primarily characterized by:
neonatal hypotonia
sexual infancy: hypogonadism
obesity
morbid obesity resulting from hyperphagi...
Article
Preaxial polydactyly
Preaxial polydactyly refers to polydactyly where the additional digit is towards the first digit of the hand (radial side) or foot (medially).
Epidemiology
Preaxial polydactyly is less common than post-axial polydactyly, with an estimated incidence of 1 in 7000.
Associations
Preaxial polydac...
Article
Primary progressive aphasia
Primary progressive aphasia was first described in 1982 and is the umbrella term for the language-variant frontotemporal dementias associated with frontotemporal lobar degeneration (FTLD) 3.
Clinical presentation
It is an insidious disorder characterized by gradual impairment of speech and lan...
Article
Progeria
Progeria is a term used for any syndrome in which a person is prematurely aged, however, it most commonly refers to Hutchinson-Gilford progeria syndrome (HGPS).
Radiographic features
Although the primary clinical manifestations of progeria include short stature and skin changes, the disease is...
Article
Progressive postnatal pansynostosis
Progressive postnatal pansynostosis (PPP) is a rare form of craniosynostosis characterized by the late fusion of all cranial sutures.
Epidemiology
This type of craniosynostosis occurs insidiously after birth and presents later in life unlike other types of craniosynostosis which occur during t...
Article
Pronator teres syndrome
Pronator teres syndrome (also called pronator syndrome) is one of three common median nerve entrapment syndromes; the other two being anterior interosseous nerve syndrome and the far more common carpal tunnel syndrome. Signs and symptoms result from compression of the median nerve in the upper f...
Article
Proteus syndrome
Proteus syndrome is a rare congenital, multisystemic, hamartomatous condition characterized by asymmetrical overgrowth of almost any part of the body and a broad spectrum of manifestations. It can affect tissue from any germinal layer. It is suspected to be a genetic condition, but a particular ...
Article
Pseudoxanthoma elasticum
Pseudoxanthoma elasticum (PXE), also known as Grönblad–Strandberg syndrome, is a systemic condition characterized by the degeneration of elastic fibers. It has multiorgan manifestations.
Epidemiology
Its prevalence is estimated to be around 1 in 25,000 9.
Clinical presentation
Patients may ...
Article
PTEN-related disease
PTEN (phosphatase and tensin homolog) gene mutation is associated with a few conditions known as PTEN-related diseases, with relatively similar clinical and radiological manifestations. They include:
Bannayan-Riley-Ruvalcaba
COLD syndrome
Cowden syndrome
Lhermitte-Duclos disease
Those not f...
Article
Pulled elbow syndrome
Pulled elbow (also known as nursemaid's elbow) is a subluxation of the radial head into the annular ligament, which usually spontaneously or easily reduces and rarely demonstrates abnormal radiographic features. It should be distinguished from dislocation of the radial head.
Epidemiology
Pull...
Article
Quadrangular space syndrome
Quadrangular space syndrome also known as quadrilateral space syndrome is an uncommon diagnosis mainly because of lack of literature on the subject and possible misdiagnosis.
Epidemiology
Quadrangular space syndrome is present on ~1% of shoulder MRIs 6.
Clinical presentation
Patients presen...
Article
Quadriceps fat pad impingement syndrome
Quadriceps (anterior suprapatellar) fat pad impingement syndrome is a rare cause of anterior knee pain although quadriceps fat pad edema may often, and possibly more commonly, be incidental 1,2.
Radiographics features
MRI
The quadriceps fat pad is enlarged with mass effect on the adjacent su...
Article
Radial tunnel syndrome
Radial tunnel syndrome is an entity that refers to entrapment (tunnel syndrome) of the radial nerve in the forearm, as it occurs in the supinator syndrome. Some authors believe this is an early form of the posterior interosseous nerve syndrome 5.
Clinical presentation
The syndrome is character...
Article
Radiologically isolated syndrome
Radiologically isolated syndrome (RIS) is defined by MRI findings meeting the McDonald criteria for multiple sclerosis in the brain and/or spinal cord in asymptomatic patients. Radiological progression usually occurs in approximately 66% of patients with RIS, while ~33% per 5-year-period will su...
Article
Raghib syndrome
Raghib syndrome is a rare developmental complex. It consists of:
persistence of the left superior vena cava
coronary sinus ostial atresia
atrial septal defect
It has also been associated with other congenital malformations including ventricular septal defects, enlargement of the tricuspid an...
Article
Raine syndrome
Raine syndrome, also known as lethal osteosclerotic bone dysplasia, is a very rare genetic disorder. Infants with this syndrome present with numerous characteristic craniofacial features as well as cerebral calcifications. Many individuals with this disorder are stillborn or die as neonates 4.
...
Article
Ramsay Hunt syndrome
Ramsay Hunt syndrome (RMS), also known as herpes zoster oticus, is shingles of the facial nerve. It is due to reactivation of the varicella zoster virus in the geniculate ganglion.
Clinical presentation
Ramsay Hunt syndrome classically presents with a triad of 3,4:
otic pain
facial nerve pal...
Article
RAPADILINO syndrome
RAPADILINO syndrome is a rare autosomal-recessive syndrome that results from mutations in the RECQL4 gene 1.
Epidemiology
RAPADILINO syndrome is a rare condition, prevalence is unknown. It is, however, more common and was first described in Finnish populations 2.
Pathology
The acronym RAPADI...
Article
Raymond syndrome
Raymond syndrome is a posterior circulatory stroke syndrome due to a lesion in the ventral medial mid-pons. It is an extremely rare condition, with only a handful of cases described in the literature.
Clinical presentation
Clinically, 2 subtypes have been reported 1:
classic type
abducens ne...
Article
Raynaud phenomenon
Raynaud phenomenon (also known as Raynaud syndrome) describes a localized vasculopathy whereby there is an exaggerated vascular response to cold temperature or emotional stresses.
Terminology
Raynaud phenomenon is classified as being either 'primary' or idiopathic, or 'secondary' to another un...
Article
Reactive arthritis
Reactive arthritis (ReA) is a sterile inflammatory monoarticular or oligoarticular arthritis that follows an infection at a different site, commonly enteric or urogenital. It is classified as a type of seronegative spondyloarthropathy.
Terminology
Reactive arthritis was formerly known as Reite...
Article
REACT syndrome
Reversible acute cerebellar toxicity (REACT) syndrome is a potentially reversible acute encephalopathic syndrome 1,2.
Epidemiology
REACT is a rare syndrome that has been associated with several opioid and chemotherapeutic agents, including Minnelide 1,2.
Clinical presentation
Patients typic...
Article
Renal cysts and diabetes syndrome
Renal cysts and diabetes syndrome (RCAD), also known as maturity-onset diabetes of the young, type 5 (MODY5), refers to the combination of renal cortical cysts and diabetes mellitus in patients with mutations in the HNF1B gene. When renal cysts are associated with these mutations without disturb...
Article
Rett syndrome
Rett syndrome is a rare neurodegenerative disease seen in young girls in the 2nd to 4th months of life. The majority of cases result from a mutation in the MECP2 gene; a more severe subset of the disease arises from a CDKL5 mutation1.
Clinical presentation
Following a period of normal developm...
Article
Rhupus syndrome
Rhupus syndrome is a term traditionally used to describe patients uncommonly having the coexistence of
systemic lupus erythematosus (SLE) and
rheumatoid arthritis (RA)
Article
Rieger anomaly
The Rieger anomaly refers to the maldevelopment of the anterior chamber of the ocular globe. The iris and cornea do not form correctly, findings including:
hypoplastic iris stroma
corectopia: an off-center pupil in the iris
colobomas of the iris (pseudopolycoria)
Patients are at increased ri...
Article
Right middle lobe syndrome
Right middle lobe syndrome refers to chronic right middle lobe collapse, without an obstructing lesion. It is usually with associated bronchiectasis.
Epidemiology
Right middle lobe syndrome is usually encountered in older adults, with a predilection for women (see Lady Windermere syndrome). I...
Article
Riley-Day syndrome
Riley-Day syndrome or familial dysautonomia is a rare neurodevelopmental genetic autosomal recessive disorder that primarily affects the autonomic nervous system 1,9.
Epidemiology
Familial dysautonomia saw in Ashkenazi Jews of Eastern European Jewish ancestry 1.
Clinical presentation
Recurre...
Article
Ritscher-Schinzel syndrome
Ritscher-Schinzel syndrome (RTSC), also known as 3C (cranio-cerebello-cardiac) syndrome, is a rare entity with a variable spectrum of CNS (primarily cerebellar), craniofacial, and congenital heart defects.
Clinical presentation
craniofacial
cleft palate
ocular coloboma
prominent occiput
lo...
Article
Roberts syndrome
Roberts syndrome, also known as Roberts-SC phocomelia syndrome, pseudothalidomide syndrome, or Appelt-Gerken-Lenz syndrome, is a rare congenital malformation syndrome.
Clinical presentation
general
intrauterine growth restriction
postnatal growth retardation
failure to thrive
thrombocytope...
Article
Robinow-Sorauf syndrome
Robinow-Sorauf syndrome (RSS) is a rare, autosomal dominant type of acrocephalosyndactyly syndrome (ACS).
Rather than being a distinct ACS, it has now generally accepted that RSS is, in fact, part of the Saethre-Chotzen syndrome phenotypic spectrum 1. This is due to similar phenotype and both b...
Article
Robinow syndrome
Robinow syndrome is a rare heterogeneous genetic disorder with at least two distinct forms.
Clinical spectrum
The syndrome can affect several systems, including:
mesomelic limb shortening: mesomelia
hemivertebrae
characteristic facies anomalies
fetal facies
hypertelorism 3
frontal bossin...
Article
Rosai-Dorfman disease
Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy or Rosai-Dorfman-Destombes disease, is a rare benign idiopathic proliferative disease that involves phagocytic histiocytes.
Epidemiology
The disease predominantly occurs in young adults with a mean age at pre...
Article
Rotational vertebral artery occlusion syndrome
Rotational vertebral artery occlusion syndrome, also known as bow hunter's syndrome, is a rare form of vertebrobasilar insufficiency secondary to dynamic compression of the usually-dominant vertebral artery.
Pathology
It has many predisposing etiologies, but is most often due to large osteoph...
Article
Rothmund-Thomson syndrome
Rothmund-Thomson syndrome (RTS) is an extremely rare autosomal recessive disorder with heterogeneous clinical features.
Clinical presentation
It is characterized by many features which include:
poikiloderma: characteristic rash, typically develops in infancy
sparse hair, eyelashes, and/or ey...
Article
Rubinstein-Taybi syndrome
Rubinstein-Taybi syndrome (RTS) is a very rare genetic multi-system disorder primarily characterized by intellectual disability, broad and often angulated thumbs and halluces, and distinctive facial features.
Epidemiology
The estimated incidence is 1 in 100,000-125,000 live births 5.
Clinical...
Article
Russell-Silver dwarfism
Russell-Silver dwarfism is a very rare syndrome representing a form of primordial dwarfism.
Epidemiology
Associations
single umbilical artery
Clinical presentation
intrauterine growth restriction: tends to give an asymmetrical IUGR
postnatal growth restriction
relatively large calvarium: ...
Article
Ruvalcaba syndrome
Ruvalcaba syndrome (also known as Ruvalcaba-Myhre-Smith syndrome) is one of a group of disorders related to the congenital skeletal disturbance. It is characterized by:
macrocephaly
hypoplastic genitalia
intellectual (not invariably) and physical disability
short stature
peculiar facies
mi...
Article
SADDAN syndrome
SADDAN syndrome is an acronym for severe achondroplasia with developmental delay and acanthosis nigricans. It is an extremely rare condition, and as the name states, comprises a combination of skeletal, brain and cutaneous anomalies.
Pathology
Genetics
The syndrome results from a mutation in ...
Article
Saethre-Chotzen syndrome
Saethre-Chotzen syndrome (also known as type III acrocephalosyndactyly) is characterized by limb and skull abnormalities.
Epidemiology
It is the most common craniosynostosis syndrome and affects 1:25 - 50,000 individuals.
Males and females are equally affected.
Clinical presentation
The spe...
Article
Sakati-Nyhan syndrome
The Sakati-Nyhan syndrome, also known as Sakati-Nyhan-Tisdale syndrome or acrocephalosyndactly type III, is an extremely rare type of acrocephalopolysyndactyly.
Its main features include:
craniofacial defects
congenital limb abnormalities
congenital heart defects
History and etymology
It w...
Article
Sampson syndrome
Sampson syndrome refers to a type of superficial endometriosis, where multiple superficial plaques may be seen scattered in the peritoneum and pelvic ligaments.
Clinical presentation
The patient may present with non-specific abdominal pain.
Radiographic features
At laparoscopy, they are typi...
Article
SAPHO syndrome
The SAPHO syndrome is an acronym that refers to a rare syndrome that is manifested by a combined occurrence of 2:
S: synovitis
A: acne
P: pustulosis
H: hyperostosis
O: osteitis
Epidemiology
It classically tends to present in young to middle-aged adults. Presentation in the pediatric popu...
Article
Schimmelpenning syndrome
Schimmelpenning syndrome is a rare and variable congenital multisystem condition characterized by extensive linear sebaceous nevi and multisystem neuroectodermal abnormalities. It is an epidermal nevus syndrome (ENS).
Clinical presentation
Classical triad including sebaceous nevi, seizures, an...
Article
Schindler disease
Schindler disease is a rare lysosomal storage disorder characterized by deficiency of alpha-N-acetylgalactosaminidase (alpha-NAGA or alpha-galactosidase B).
Epidemiology
It is a rare disease with autosomal recessive inheritance.
Clinical presentation
Age and severity of presentation depends ...
Article
Sclerosteosis
Sclerosteosis is a rare autosomal recessive bone dysplasia resulting in sclerosis and hyperostosis, particularly of the skull, mandible and tubular bones. It is closely related to Van Buchem disease 1.
Epidemiology
Sclerosteosis is a very rare disease, with only around 100 cases reported. Ther...
Article
Seatbelt syndrome
The seatbelt syndrome is the constellation of traumatic thoracic, abdominal and/or vertebral column injuries associated with three-point seatbelts 1,2:
bowel perforation
mesenteric tear
sternal fracture
lumbar spine fracture
female breast trauma
Article
Seckel syndrome
Seckel syndrome is an autosomal recessive congenital dwarfing disorder.
Epidemiology
The estimated incidence is ~1:10,000. There is no recognized gender predilection.
Clinical presentation
It is clinically characterized by many features including:
intrauterine growth restriction
postnatal ...
Article
Segmental arterial mediolysis
Segmental arterial mediolysis (SAM) is an increasingly recognized vascular disease of the middle-aged and elderly and a leading cause of spontanoeus intra-abdominal hemorrhage. It is characterized by fusiform aneurysms, stenoses, dissections and occlusions within splanchnic arterial branches. Im...
Article
Sepsis
Sepsis is a syndrome, with a poorly understood pathogenesis, characterized clinically by a recognized set of signs and symptoms in someone with presumed infection.
Terminology
Sepsis was defined by The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) in 2016 as ...
Article
Septic-embolic encephalitis
Septic-embolic encephalitis, also known as septic-embolic brain abscess, refers to a focal or diffuse brain infection, ischemic and hemorrhagic damages following infective thromboembolism from any part of the body. It is usually caused by bacterial infections from endocarditis.
Terminology
Se...
Article
Serrated polyposis syndrome
Serrated polyposis syndrome (SPS), also called hyperplastic polyposis syndrome, is one of numerous polyposis syndromes and is characterized by the presence of multiple serrated polyps or a mixture of serrated and hyperplastic polyps, with the exact number required for diagnosis dependent on loca...
Article
Severe acute respiratory syndrome
The severe acute respiratory syndrome (SARS) is a zoonotic illness caused by severe acute respiratory syndrome-related coronavirus (SARS-CoV-1), a coronavirus. The disease was first seen in the city of Foshan in Guangdong Province in China in 2002 and was traced back to the Himalayan (masked) p...
Article
Sezary syndrome
Sézary syndrome (SS) is a type of primary cutaneous T-cell lymphoma.
Clinical presentation
It is clinically characterized by an extensive erythematous rash covering most of the body as well as the presence of malignant lymphocytes in the blood.
History and etymology
It is named after Albert...
Article
Shapiro syndrome
Shapiro syndrome is a very rare condition characterized by the triad of episodic hypothermia, hyperhidrosis, and agenesis of the corpus callosum 1. A similar syndrome, characterized by episodic hyperthermia and agenesis of the corpus callosum, has been termed reverse Shapiro syndrome 2.
Epidemi...
Article
Sheehan syndrome
Sheehan syndrome is a rare cause of pituitary apoplexy and hypopituitarism. It only occurs in postpartum females who experience large volume hemorrhage and hypovolemic shock, either during delivery or afterward with resultant necrosis of anterior pituitary cells 4.
Epidemiology
Advances in obs...
Article
Shone syndrome
Shone syndrome, also known as Shone complex, is a rare syndrome characterized by left-sided, obstructive congenital heart defects.
Epidemiology
Shone syndrome is thought to be very rare, accounting for less than 1% of all congenital heart disease 1.
Clinical presentation
Patients, usually ne...
Article
Short lasting unilateral neuralgiform headache attacks
Short lasting unilateral neuralgiform headache attacks can present with either conjunctival injection and tearing (SUNCT) or with cranial autonomic symptoms (SUNA) are rare headache syndromes that belong to a larger group of headaches known as trigeminal autonomic cephalgia and can present very ...
Article
Short rib polydactyly syndrome
Short rib polydactyly syndrome(s) (SRPS) comprise a rare group of severe osteochondrodysplasias. There are four major recognized types present:
type I: Saldino-Noonan type
type II:: Majewski type
type III: Verma-Naumoff type
type IV: Beemer-Langer type
There may also be other very rare type...
Article
SHORT syndrome
SHORT syndrome refers to an acronym which primarily comprises of the following features:
S: short stature
H: hyperextensibility of joints and/or inguinal hernia
O: ocular depression
R: Rieger anomaly
T: teething delay
In addition to these there can be numerous associated minor features whi...
Article
Shrinking lung syndrome
Shrinking lung syndrome refers to a rare thoracic complication of systemic lupus erythematosus (SLE) characterized by:
unexplained dyspnea
restrictive pattern on pulmonary function tests
elevated hemidiaphragm
Epidemiology
As with SLE in general, it is thought to carry a increased female pr...
Article
Shwachman-Diamond syndrome
Shwachman-Diamond syndrome (SDS) or Shwachman-Bodian-Diamond syndrome (SBDS) is a rare autosomal recessive disorder characterized by 1 :
exocrine pancreatic insufficiency
metaphyseal chondrodysplasia
bone marrow hypoplasia (cyclic neutropenia)
Epidemiology
Shwachman-Diamond syndrome is a ra...
Article
Shy-Drager syndrome
The Shy-Drager syndrome is a neurodegenerative disease, and one of the manifestations of multiple systemic atrophy (MSA).
Terminology
It is important to note that the current belief that olivopontocerebellar degeneration, Shy-Drager syndrome and striatonigral degeneration are different manifes...
Article
Sickle cell disease (acute chest syndrome)
Acute chest syndrome (ACS) in sickle cell disease is a leading thoracic complication - as well as leading cause of mortality - in those affected by sickle cell disease. The diagnosis is made on the combination of new pulmonary opacity on chest x-ray with at least one new clinical symptom or sign...
Article
Silent sinus syndrome
The silent sinus syndrome represents maxillary sinus atelectasis that results in painless enophthalmos, hypoglobus and facial asymmetry 1-3. Some authors restrict the term to patients with no history of sinusitis, trauma or surgery 2. Some authors suggest that is part of the spectrum of chronic ...
Article
Simpson-Golabi-Behmel syndrome
Simpson-Golabi-Behmel syndrome is a rare X-linked recessive disorder of pre- and postnatal overgrowth syndrome represented by mild to severe intellectual disability 3,7, anomalies of the musculoskeletal system, cardiovascular system, central nervous system, renal and gastrointestinal tract were ...
Article
Sinus tarsi syndrome
Sinus tarsi syndrome (STS) is the clinical syndrome of pain and tenderness of the lateral side of the hindfoot, between the ankle and the heel. Imaging often demonstrates the ligaments and soft tissues in the sinus tarsi are injured.
Epidemiology
Sinus tarsi syndrome has been described in danc...
Article
Sjögren-Larsson syndrome
Sjögren-Larsson syndrome is a rare inherited autosomal recessive neurocutaneous syndrome and leukodystrophy characterized by the clinical triad of ichthyosis, intellectual disability, and spastic diplegia or tetraplegia.
Epidemiology
Although considered very rare, the exact prevalence is not k...
Article
Sjögren syndrome
Sjögren syndrome, or Sjögren disease, is an autoimmune condition of the exocrine glands that produce tears and saliva.
Epidemiology
Sjögren syndrome is the second most common autoimmune disorder after rheumatoid arthritis. There is a recognized female predilection with F:M ratio of ≈9:1. Pati...
Article
Slit ventricle syndrome
Slit ventricle syndrome refers to cerebrospinal fluid shunt-related symptoms in the setting of small ventricles demonstrated on radiologic studies.
Clinical presentation
The presence of characteristic symptoms is required to diagnose slit-ventricle syndrome and must be distinguished from slit-...
Article
Small for size graft syndrome (liver graft)
Small for size syndrome (SFSS) is a clinical syndrome caused by the transplantation of a liver graft that is too small for a recipient. It occurs when the graft‐to‐recipient weight ratio (GRWR ) is less than 0.8% or a graft volume to standard liver volume ratio (GV/SLV) is less than 35%.
Clinic...
Article
SMART syndrome
SMART syndrome, an acronym for stroke-like migraine attacks after radiation therapy, is an uncommon delayed complication of cerebral radiation therapy.
Clinical presentation
Patients usually present years after radiation therapy (6-30 years in a case series) with seizures and subacute stroke-l...
Article
Smith-Lemli-Opitz syndrome
Smith-Lemli-Opitz syndrome (SLOS) also known as 7-dehydrocholesterol reductase deficiency, is an inborn error of cholesterol synthesis.
Epidemiology
The estimated incidence is at 1:20,000-40,000 live births. Prevalence may be greater in Nordic countries.
Associations
Hirschsprung disease
C...
Article
Smith-Magenis syndrome
Smith-Magenis Syndrome (SMS) is a rare genetic syndrome which results from an interstitial deletion in chromosome 17p11.2.
Terminology
The condition is known by several other names which are all similar variants related to its underlying karyotype: 17p deletion syndrome, 17p11.2 monosomy, chro...
Article
Snapping hip syndrome
Snapping hip syndrome (also known as coxa saltans or dancer’s hip) refers to a situation where there is an audible snapping sound produced during motion of the hip.
Epidemiology
Some reports suggest that up to 10% of population may have this to some degree 8.
Pathology
This condition is cla...
Article
Sneddon syndrome
Sneddon syndrome is a type of systemic non-inflammatory vasculopathy characterized by livedo reticularis and progressive and occlusive cerebrovascular thrombosis involving the medium-sized arteries.
Clinical presentation
livedo reticularis as a skin manifestation
progressive cerebral stroke...
Article
Solitary rectal ulcer syndrome
Solitary rectal ulcer syndrome (SRUS) is a chronic, benign disorder characterized by the presence of an abnormality of the rectum in persons who have a long history of straining during defecation. It is a misnomer because only a third of patients have a solitary ulcer, and many have no ulcers at...
Article
Sotos syndrome
Sotos syndrome it is an autosomal dominant syndrome considered as a form of cerebral gigantism, most characterized by the prenatal and postnatal overgrowth.
Epidemiology
There is no ethnic group predominance and has been detected throughout the world. The prevalence is not known but is estimat...
Article
Spigelian-cryptorchidism syndrome
Spigelian-cryptorchidism syndrome ( also known as Raveenthiran syndrome ) is the association of Spigelian hernias and cryptorchidism in children.
Pathology
It is reported that ~50% (range 28-75%) range of pediatric patients with Spigelian hernias will have ipsilateral cryptorchidism 1,2.
Al...
Article
Spinal cord injury
Spinal cord injury (SCI) can be traumatic or non-traumatic (i.e. neoplastic/stenosis) but the syndromes associated with spinal cord injury can be seen in all etiologies.
Injury to the spinal cord can be incomplete or complete and depends upon the mechanism of injury. This is important as differ...
Article
Spondylocostal dysostosis
Spondylocostal dysostosis (SCDO) is a rare condition characterized by short-trunk dwarfism secondary to developmental anomalies of the vertebrae and ribs. Previously the condition Jarcho-Levin syndrome (also known as spondylothoracic dysostosis) was grouped together with spondylocostal dysostosi...
Article
Spondyloepiphyseal dysplasia
Spondyloepiphyseal dysplasia is a form of skeletal dysplasia mainly involving the spine and proximal epiphyses.
Clinical presentation
short neck
short trunk with protruding abdomen
normal IQ
spine
atlanto-axial instability
craniovertebral junction stenosis
platyspondyly
limbs
mostly ...
Article
Stauffer syndrome
Stauffer syndrome is paraneoplastic nephrogenic hepatomegaly. It most commonly occurs in the setting of renal cell carcinoma, and is the enlargement of the liver without hepatic metastases. It is a cause of cholestasis and cholestatic jaundice.
History and etymology
It is named after Maurice ...
Article
Stevens Johnson syndrome
Stevens-Johnson syndrome (SJS) is an acute inflammatory skin condition.
Terminology
SJS is on a spectrum of disease with toxic epidermal necrolysis syndrome (TENS) at the more severe end. Terminology depends on how much of the body surface area is involved 1,2:
SJS: <10%
SJS-TENS overlap: 1...
Article
Stewart-Treves syndrome
Stewart-Treves syndrome refers to an angiosarcoma seen in the setting of lymphedema 1.
It was classically attributed to lymphedemas induced by radical mastectomy to treat breast cancer. Nowadays, we know that it can arise in chronically lymphedematous regions of any cause 2.
The incidence is ...
Article
Stickler syndrome
Stickler syndrome refers to a group of disorders primarily affecting connective tissue.
Pathology
Several gene mutations have been identified dependent on specific subtypes which include:
Stickler syndrome type I: COL2A1
Stickler syndrome type II: COL9A1
Stickler syndrome type III: COL11A1
...
Article
Stiff person syndrome
Stiff person syndrome, previously known as stiff man syndrome, is a very rare neuromuscular disease.
Epidemiology
Onset is usually between 30 and 50 years of age. An association with autoimmune disease and various malignancies is described and these are thought to play a role in the pathophysi...
Article
Straight back syndrome
Straight back syndrome refers to decreased thoracic kyphosis ("flattening") and decreased anteroposterior thoracic diameter, such that there is compression of cardiovascular or bronchial structures.
It should not be confused with flat back syndrome, which refers to decreased lumbar lordosis, o...
Article
Sturge-Weber syndrome
Sturge-Weber syndrome, or encephalotrigeminal angiomatosis, is a phakomatosis characterized by facial port wine stains and pial angiomas.
It is part of a wide spectrum of possible phenotypes included in the craniofacial arteriovenous metameric syndrome (CAMS).
Epidemiology
Sturge-Weber syndr...
Article
Subacute encephalopathy with seizures in alcoholics (SESA syndrome)
Subacute encephalopathy with seizures in alcoholics (SESA syndrome) is a rare complication of chronic excessive alcohol consumption that can present with seizures and a variety of neurological deficits.
Epidemiology
SESA syndrome is rare and seen in alcoholics who are not undergoing withdrawa...
Article
Subclavian steal syndrome
Subclavian steal syndrome and subclavian steal phenomenon both result from severe proximal subclavian artery stenosis or occlusion resulting in retrograde flow in the ipsilateral vertebral artery.
Terminology
Subclavian steal phenomenon refers to steno-occlusive disease of the proximal subclav...
Article
Subependymal hamartoma
Subependymal hamartomas are seen in patients with tuberous sclerosis. They are located along the ventricles and are mostly asymptomatic. As with other hamartomas, they grow at the same rate as the surrounding tissues.
On imaging, they appear as small intraventricular masses, smaller than 1 cm, ...
Article
Sulcal artery syndrome
Sulcal artery syndrome is a rare cause of spinal cord infarction involving the territory of one of the sulcal arteries, which are penetrating branches of the anterior spinal artery, each vessel supplying either left or right side of the cord, but not both. The result is an incomplete Brown-Séqua...