18q syndrome is a rare chromosomal anomaly where there is a deletion of part of the long arm of chromosome 18. Associated symptoms and findings vary widely, as does their severity. Characteristic features include short stature, mental retardation and hypotonia, facial and distal skeletal abnorma...
Acute spinal cord ischaemia syndrome (ASCIS) is uncommon, but usually presents with profound neurological signs and symptoms, and the prognosis is poor.
Acute spinal cord ischaemia syndrome represents only 5-8% of acute myelopathies 4,5 and <1% of all strokes 7. The demographic o...
Adie syndrome consists of a classic triad of:
absent deep tendon reflexes, e.g. ankle jerk
an Adie pupil: tonically dilated and responds poorly or not at all to light
It is thought to result from damage to the ciliary ganglion and the dorsal root ganglion by viral or bacterial in...
Aicardi syndrome is a rare severe developmental disorder. It results from an X-linked genetic defect that is fatal in males and therefore only manifests in females (except for rare 47-XXY cases).
The typical presentation in infancy is with a triad of:
infantile spasms: salaa...
Anterior choroidal artery syndrome is a rare entity characterised by the triad of hemiplegia, hemianaesthesia and contralateral hemianopia as a result of cerebral infarction in the anterior choroidal artery territory.
The syndrome may also be associated with neuropsychological disorders, includ...
Anterior cord syndrome (also known as Beck's syndrome or anterior spinal artery syndrome) is a clinical subset of spinal cord injury syndromes, due to ischaemia/infarction of the anterior two-thirds of the spinal cord, typically sparing the posterior third.
Antiphospholipid syndrome is a systemic autoimmune disorder. It is usually defined as the clinical complex of vascular occlusion and ischaemic events occurring in patients who have circulating antiphospholipid antibodies.
Patients have circulating antiphospholipid antibodies cross-re...
Asymmetric ventriculomegaly, interhemispheric cyst and dysgenesis of the corpus callosum (AVID) is a triad of congenital cerebral anomalies.
markedly asymmetric enlargement of the lateral ventricles may be the initial finding on routine fetal morphology ultrasound.
Ataxia telangiectasia is a rare multisystem disorder which carries an autosomal recessive inheritance, sometimes classified as a phakomatosis. It is characterised by multiple telangiectasias, cerebellar ataxia, pulmonary infections and immunodeficiency.
On brain imaging, it usually demonstrate...
Babinski-Nageotte syndrome is thought to be a brainstem stroke syndrome in between that of the hemimedullary syndrome (Reinhold syndrome) and the lateral medullary syndrome (Wallenberg syndrome) 1,2.
In many texts this eponymous syndrome is incorrectly attributed to actually being...
Bannayan–Riley–Ruvalcaba syndrome (BRRS or BRR syndrome) is a very rare autosomal dominant hamartomatous disorder caused by a mutation in the PTEN gene. It is considered in the family of hamartomatous polyposis syndrome.
There are no formal diagnostic criteria for this disease, but characterist...
Bardet-Biedl syndrome (BBS), previously known as the Laurence-Moon-Bardet-Biedl syndrome (LMBBS), is a rare autosomal recessive hereditary condition.
The clinical spectrum includes:
retinal anomalies: similar to that of retinitis pigmentosa
Benedikt syndrome, or paramedian midbrain syndrome, is a midbrain stroke syndrome that involves the fascicles of the oculomotor nerve and the red nucleus.
ipsilateral CN III palsy 1-4
crossed hemiataxia 1-4
crossed choreoathetosis 1-4
It is usually caused by...
Benign paroxysmal positional vertigo (BPPV) is one of the most common causes of vertigo. It occurs secondary to change in posture and typically is associated with nystagmus. The aetiology is thought to be due to changes of position of the otoliths in the inner ear, most commonly into the posteri...
Brissaud-Sicard syndrome is a very rare pontine stroke syndrome that involves the anterolateral and inferior pons.
Classically, the syndrome presents as ipsilateral facial cramps and contralateral hemiparesis 1-3.
It has been postulated that the syndrome is ca...
Brown-Séquard syndrome is the result of a hemicord lesion (i.e. damage or impairment to the left or right side of the spinal cord).
Due to some fibres crossing within the cord whilst others cross in the brainstem, the neurology is bilateral, namely 1:
The Brown syndrome refers to an inability of a patient to perform an upward gaze while the eye is adducted due to an abnormality of the superior oblique tendon sheath complex.
History and etymology
It was first described by Allan Brown in 1950 1.
Cauda equina syndrome refers to a collection of symptoms and signs that result from severe compression of the descending lumbar and sacral nerve roots. It is considered a diagnostic and surgical emergency.
Cauda equina syndrome is rare with prevalence estimated at approximately 1...
Caudal regression syndrome (CRS) represents a spectrum of structural defects of the caudal region. Malformations vary from isolated partial agenesis of the coccyx to lumbosacral agenesis.
Caudal regression syndrome is rare, with an estimated incidence of 1:7500-100,000 7,10.
CEC syndrome refers to the combination of coeliac disease, epilepsy and bilateral occipital calcifications. This is also known as Gobbi syndrome. Patients with cerebral calcifications and coeliac disease without epilepsy are considered as having an incomplete form of CEC syndrome 1.
Central cord syndrome is the most common type of incomplete spinal cord injury, accounting for ~10% of all spinal cord injuries. As the name implies, this syndrome is the result of a contusion of the central portion of the cervical spinal cord.
Most often central cord syndrome occ...
Charcot-Marie-Tooth (CMT) disease, also known as hereditary motor and sensory neuropathy (HMSN), is the most commonly inherited neuropathy of lower motor (to a lesser degree sensory) neurons.
The prevalence of CMT in one Norwegian study was 82.3 cases per 100,000 people 4.
Chinese paralytic syndrome also known as acute motor axonal neuropathy (AMAN) is characterised progressive symmetric flaccid paralysis with areflexia. It is a pure motor axonopathy and a variant of Guillain-Barré syndrome
Claude syndrome is one of the brainstem stroke syndromes in which there is infarction of the dorsomedial aspect of the midbrain.
Clinical picture is characteristic and includes ipsilateral oculomotor nerve palsy and contralateral upper and lower limb ataxia 1-4.
Cockayne syndrome is a rare autosomal recessive dysmyelinating disease. Cockayne syndrome is classified among the childhood leukodystrophies, and brain imaging findings are cardinal features suggesting the diagnosis of Cockayne syndrome. Previously published Cockayne syndrome imaging studies hav...
Coffin-Siris syndrome, first described in 1970, is a rare genetic abnormality.
It occurs more frequently in females (with a M:F of ~4:1).
It is thought most likely to relate to a gene on chromosome 7, however its exact location has yet to be determined.
Conus medullaris syndrome is caused by an injury or insult to the conus medullaris and lumbar nerve roots. It is a clinical subset of spinal cord injury syndromes. Injuries at the level of T12 to L2 vertebrae are most likely to result in conus medullaris syndrome.
The conus medullari...
Cortical blindness is a condition resulting from lesions in the primary visual cortex (V1) characterised by visual impairment but with an intact anterior visual pathway (normal pupillary reflexes and fundal appearance).
The degree of visual impairment is related to the extent...
Dandy-Walker variant (DWv) is a less severe posterior fossa anomaly than the classic Dandy-Walker malformation (DWM) and is considered being on the lesser end of the disease spectrum in the Dandy-Walker continuum.
This term was created to include those malformations that do not mee...
Dorsal brainstem syndrome is a rare subset of hypoxic ischaemic encephalopathy in neonates limited to the isolated involvement of the brainstem with sparing of the supratentorial brain. Due to its subtle imaging features it is often undiagnosed.
Injuries involving the teg...
Down syndrome (or trisomy 21) is the most common trisomy and also the commonest chromosomal disorder. It is a major cause of intellectual disability, and also has numerous multi-system manifestations.
According to the world health organisation (WHO), the approximate worldwide inci...
Dravet syndrome, previously known as severe myoclonic epilepsy of infancy (SMEI), is a rare form of epilepsy usually presenting in the first 1-2 years of life.
The typical presentation occurs during the first six months to one year of life as tonic-clonic seizures in a fe...
Dyke-Davidoff-Masson syndrome (DDMS) is a condition chararacterised by hemi cerebral atrophy/hypoplasia secondary to brain insult usually in fetal or early childhood period and is accompanied by ipsilateral compensatory osseous hypertrophy and contralateral hemiparesis.
It is characterised by:
Facial colliculus syndrome refers to a constellation of neurological signs due to a lesion at the facial colliculus, involving:
abducens nerve (CN VI) nucleus
facial nerve (CN VII) fibres at the genu
medial longitudinal fasciculus
lower motor neuron facial nerve palsy ...
Fahr syndrome, also known as bilateral striatopallidodentate calcinosis, is characterised by abnormal vascular calcium deposition, particularly in the basal ganglia, cerebellar dentate nuclei, and white matter, with subsequent atrophy.
It can be either primary (usually autosomal dominant) or se...
Familial multiple cavernous malformation syndrome(s) are uncommon, accounting for only a minority of cavernous malformations.
It has been more frequently reported in patients of Hispanic descent 1.
The presentation is most commonly with seizures (38-55%) 1 ...
Fat embolism syndrome (FES) is a rare clinical condition caused by circulating fat emboli leading to a multisystemic dysfunction. The classical clinical triad consists of:
It occurs in ~2.5% (range 0.5-4%) of th...
Foster Kennedy syndrome describes the clinical syndrome of unilateral optic atrophy with contralateral papilloedema caused by an ipsilateral compressive mass lesion.
The syndrome consists of two cardinal features:
ipsilateral optic nerve atrophy presenting with central s...
Frontonasal dysplasia, also known as median cleft face syndrome, is a rare disorder characterised by midline defects involving the face, head, and central nervous system.
Frontonasal dysplasia is considered to be a very rare condition, with approximately 100 cases having been repo...
Gasperini syndrome is a rare pontine stroke syndrome that involves the caudal pons tegmentum.
Classically, the syndrome presents with 1-3:
involvement of the CN V nucleus: ipsilateral facial sensory loss
involvement of the CN VI nucleus: ipsilateral impaired eye abducti...
Gerstmann-Straussler-Scheinker disease is a very rare type of human transmissible spongiform encephalopathy. It manifests with dementia and/or ataxia and is due to a mutation in the prion protein (PRNP) gene, which is inherited in an autosomal dominant pattern.
History and etymology
It is par...
Gerstmann syndrome, also known as angular gyrus syndrome, is a dominant hemisphere stroke syndrome consisting of four components:
agraphia or dysgraphia
acalculia or dyscalculia
Pure Gerstmann syndrome is said to be without aphasia.
History and ety...
Gomez-Lopez-Hernandez syndrome, also known as cerebellotrigeminal-dermal dysplasia, is a rare phakomatosis characterised by rhombencephalosynapsis, parietal-occipital scalp alopecia, brachycephaly, facial malformations and trigeminal anesthesia.
History and etymology
It is named after Manuel ...
Gradenigo syndrome consists of the triad of:
abducens nerve palsy, secondary to involvement of the nerve as it passes through Dorello canal
retro-orbital pain, or pain in the cutaneous distribution of the frontal and maxillary divisions of the trigeminal nerve, due to extensi...
Guillain-Barré syndrome (GBS) is defined as a heterogeneous group of autoimmune polyradiculopathies, involving sensory, motor and autonomic nerves. It is the most common cause of rapidly progressive flaccid paralysis. It is believed to be one of a number of related conditions, sharing a similar ...
Heerfordt(-Waldenström) syndrome or uveoparotid fever is a variant of sarcoidosis, comprising of:
ocular involvement (anterior uveitis)
The exact prevalence is unknown, as only isolated case reports exist. Neurologic involvement may occur...
Hemiconvulsion-hemiplegia epilepsy syndrome (HHE) is a clinical syndrome of infancy or early childhood that is associated with seizures, cerebral hemiatrophy and transient or permanent epilepsy.
It refers to the characteristic holohemispheric global atrophy of one hemisphere, that is independen...
Hemimedullary syndrome, also known as Reinhold syndrome, occurs as a result of the occlusion of the ipsilateral vertebral artery proximal to the posterior inferior cerebellar artery and its anterior spinal artery branches 1-3. This situation causes lateral medullary infarct and medial medullary ...
Hereditary haemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu syndrome, is a rare inherited disorder characterised by abnormal blood vessel formation in the skin, mucous membranes, and organs including the lungs, liver, and central nervous system.
HGPPS is a rare autosomal recessive AR congenital anomaly caused by mutation of ROBO3 gene on chromosome 11.
Abnormal horizontal gaze while normal vertical gaze and kyphoscoliosis. Horizontal gaze requires the action of ipsilateral abducent nerve and contralateral oculomo...
Hyperperfusion syndrome after carotid endarterectomy (CEA) or carotid artery stenting (CAS) is a rare complication.
Hyperperfusion occurs in ~7.5% (range 1-14%) of patients but only a minority (~1.5%) of patients are symptomatic 1,2, with incidence being reported slightly more af...
Hypomelanosis of Ito, also known as incontinentia pigmentiachromians, is the third most frequent phakomatosis, involving a wide spectrum of defects in multiple organ systems.
The prevalence is unknown, being reported since 1 per 8000 patients in a general paediatric hospital 3 to ...
Immune reconstitution inflammatory syndrome (IRIS) is paradoxical deterioration of a pre-existing illness following abrupt improvement in an individual's immune function. It is classically seen in HIV/AIDS patients following initiation of highly active anti-retroviral therapy (HAART). Increasing...
Incontinentia pigmenti, also known as Bloch-Sulzberger syndrome, is a rare condition that can affect many body systems, specially the skin. As an X-linked dominant genetic disorder, it occurs much more often in females than in males.
Incontinentia pigmenti is rare and the true pre...
Inferior medial pontine syndrome, also known as Foville syndrome, is one of the brainstem stroke syndromes occurring when there is infarction of the medial inferior aspect of the pons due to occlusion of the paramedian branches of the basilar artery 1-3. This infarction involves the following 1-...
Internuclear ophthalmoplegia (INO) describes a clinical syndrome of impaired adduction in one eye with dissociated horizontal nystagmus of the other abducting eye, due to a lesion in the medial longitudinal fasciculus (MLF) ipsilateral to the eye unable to adduct. It is a common finding in multi...
Jaffe-Campanacci syndrome is characterised by:
multiple non-ossifying fibromas of the long bones and jaw
café au lait spots
hypogonadism or cryptorchidism
giant cell granuloma of the jaw
Lacunar stroke syndrome (LACS) is a description of the clinical syndrome that results from a lacunar infarct.
Each of the five classical lacunar syndromes has a relatively distinct symptom complex. Symptoms may occur suddenly, progressively, or in a fluctuating manner (e.g. the capsular warnin...
Large vestibular aqueduct syndrome (LVAS) refers to the presence of congenital sensorineural hearing loss with an enlarged vestibular aqueduct. It is thought to be one of the most common congenital causes of sensorineural hearing loss (SNHL).
SNHL starts in childhood and...
Lateral medullary syndrome (or Wallenberg syndrome) is a clinical syndrome caused by an acute ischemic infarct of the lateral medulla oblongata. This is most commonly due to occlusion of the intracranial portion of the vertebral artery followed by PICA and its branches 1-3. This syndrome is cha...
The lateral meningocele syndrome is an extremely rare hereditary connective tissue disorder characterized by multiple lateral lumbar meningoceles, distinctive facial features, joint hypermobility, hypotonia, skeletal abnormalities, congenital cardiovascular malformations, urogenital anomalies an...
Lateral pontine syndrome, also known as Marie-Foix syndrome or Marie-Foix-Alajouanine syndrome, refers to one of the brainstem stroke syndromes of the lateral aspect of the pons.
There is a characteristic clinical picture from the involvement of the following pontine stru...
Leukoencephalopathy with calcifications and cysts, also known as Labrune syndrome, is a rare condition that consists of a triad of leukoencephalopathy, cerebral calcifications and oedematous cysts.
Leukoencephalopathy with calcifications and cysts is an extremely rare condition, w...
Locked-in syndrome is a condition that can occur as a result of a stroke involving the brainstem; the stroke damages the ventral brainstem, corresponding to the pyramidal bundles.
The infarct is pontine; the midbrain is preserved. The oculomotor nerve III is intact so the...
Man-in-the-barrel syndrome is a neurological syndrome characterised by bilateral brachial muscular weakness.
This syndrome is usually caused by bilateral cerebral lesions in the border zone between the anterior and middle cerebral arteries.
The syndrome has been described...
Marchiafava-Bignami disease (MBD) is a rare CNS disorder usually seen in the context of alcoholism and malnutrition. The condition classically involves the corpus callosum with necrosis and demyelination.
MBD is in most instances seen in chronic alcoholics, and as such the epidem...
Medial medullary syndrome, also known as Déjerine syndrome, represents less than 1% of brainstem stroke syndromes 1,2. Thrombotic or embolic occlusion of small perforating branches from vertebral or proximal basilar artery supplying the medial aspect of medulla oblongata cause this rare syndrome...
Megalencephaly-capillary malformation (MCAP) syndrome, also known as macrocephaly-capillary malformation syndrome, is a rare and well described genetic disorder caused by somatic mutations in the PIK3CA gene on chromosome 3q26 and characterised by early brain overgrowth and body morphogenesis an...
Menkes disease, also known as trichopoliodystrophy or Kinky hair kinky vessel syndrome, is an X-linked recessive disorder that results in a derangement in copper handling. It results in low copper levels and subsequently, deficiency in copper dependant mitochondrial enzymes.
MERRF (myoclonic epilepsy with red ragged fibres) is a rare, multisystem mitochondrial disorder.
Patients usually present in late adolescence or early adulthood with 1,2,3
vision and/or hearing loss
Metronidazole, which is used to treat a wide variety of bacterial and protozoal infections can, in exceedingly rare cases, lead to central nervous system toxicity.
In a review of the case literature 1, affected patients range widely in age, with the peak incidence occurring in the...
Millard-Gubler syndrome, also known as ventral pontine syndrome, is one of the crossed paralysis syndromes, which are characterised by cranial nerves VI and VII palsies with contralateral body motor or sensory disturbances 1-3.
ipsilateral facial and contralateral body he...
Möbius syndrome, also known as congenital facial diplegia syndrome, is a rare congenital condition characterised by the absence or underdevelopment of the abducens nerve (CN VI) and facial nerve (CN VII) nuclei.
Möbius syndrome is rare with an estimated incidence of ~1 case per 10...
Morgagni syndrome consists of the triad of:
hyperostosis frontalis interna
virilism and hirsutism
History and etymology
It was first described in 1765 by the Italian anatomist and pathologist Giovanni Battista Morgagni (1682-1771)
Morning glory disc anomaly (MGDA),also known as morning glory syndrome, is a rare congenital malformation of the optic nerve which is frequently associated with midline abnormalities of the brain and skull 1.
Morning glory disc anomaly is rare and is more commonly found in females...
Morvan syndrome, also known as Morvan fibrillary chorea, is a rare syndrome thought to be either paraneoplastic or autoimmune in origin.
It is characterised by:
Voltage gated pot...
Multiple endocrine neoplasia type I (MEN1), also known as Wermer syndrome, is an autosomal dominant genetic disease that results in proliferative lesions in multiple endocrine organs, particularly the pituitary gland, islet cells of the pancreas and parathyroid glands.
There are other multiple...
Multiple system atrophy (MSA) is a sporadic neurodegenerative disease (one of the synucleinopathies) characterised by varying degrees of cerebellar ataxia, autonomic dysfunction, parkinsonism and corticospinal dysfunction.
Multiple systemic atrophy is a sporadic disease, with a p...
Neck tongue syndrome (NTS) is rare and comprises altered sensation in one side of the tongue aggravated by neck movement, with ipsilateral neck pain 1.
NTS is seen in a wide range of ages but is more commonly reported in older children and young adults 1-3.
Neurocutaneous melanosis or neurocutaneous melanomatosis, is a rare sporadic phakomatosis characterised by multiple congenital cutaneous nevi and meningeal melanocytosis / meningeal melanomatosis.
Neurocutaneous melanosis tends to be diagnosed in the first few years of life with ...
Neuroferritinopathy, also known as neurodegeneration with brain iron accumulation type 2 (NBIA type 2), is a disorder of iron metabolism caused by a mutation in the ferritin light chain 1 gene (FTL1) on chromosome 19.
Neuroferritinopathy is a rare disorder first described in 2001 ...
Neurofibromatosis type 1 (NF1), also known as von Recklinghausen disease, is a multisystem neurocutaneous disorder, the most common phakomatosis, and a RASopathy. Additionally, it is also one of the most common inherited CNS disorders, autosomal dominant disorders and inherited tumour syndromes....
Cutaneous manifestations of neurofibromatosis type 1 (NF1), or von Recklinghausen disease, are the heralding features of this multisystem neurocutaneous disorder, which is the most common phakomatosis.
Nowadays genetic testing permits the laboratory diagnosis of NF1 in as many as 95%, although ...
Thoracic manifestations of neurofibromatosis type 1 (NF1), or von Recklinghausen disease, are related to pulmonary and mediastinal features of this multisystem neurocutaneous disorder, which is the most common phakomatosis.
For other thoracic manifestations as focal thoracic scoliosis, enlarged...
Niacin (vitamin B3) deficiency, also known as pellagra, is a multisystem disease which involves the skin, gastrointestinal tract and central nervous system.
It use to be widespread until the early twenty century, but after fortification of flour with niacin it was practically era...
Nijmegen breakage syndrome (NBS) (also known as Seemanova syndrome or Berlin breakage syndrome) is a rare autosomal recessive syndrome of chromosomal instability.
Main clinical features are:
microcephaly present at birth and
progressive with age
dysmorphic facial feat...
Nothnagel syndrome is a rare midbrain stroke syndrome that involves the tectum of the midbrain, including the quadrigeminal plate 1-4.
Classically, the syndrome involves the oculomotor nerve fascicles and superior cerebellar peduncle, leading to ipsilateral CN III palsy a...
Ophelia syndrome is the association of Hodgkin lymphoma with an autoimmune limbic encephalitis, as a result of anti-metabotropic glutamate receptor 5 antibodies (mGluR5) 1.
Organophosphate poisoning is an important cause of acute neurological dysfunction and respiratory distress.
Organophosphate poisoning is common, often as a result of suicidal ingestion (acute high-level exposure) or occupational exposure to pesticides (chronic low-level exposure) ...
Osteopathia striata with cranial sclerosis (OS-CS) is a clinically separate entity from osteopathia striata (Voorhoeve disease). Bony changes on their own are typically incidental and autosomal dominant, whereas OS-CS is a multisystem, X-linked dominant disorder.
OS-CS is extremel...
Pantothenate kinase-associated neurodegeneration (PKAN), previously known as Hallervorden-Spatz syndrome, is an autosomal recessive disorder causing involuntary spasticity and progressive dementia. It is a subset of neurodegeneration with brain iron accumulation (NBIA).
Paradoxical brain herniation, also known as sinking skin flap syndrome (SSFS), is a rare and potentially fatal entity complicating decompressive craniectomy.
Atmospheric pressure exceeding intracranial pressure at the craniectomy results in displacement of the brain across various i...
Paraneoplastic syndromes occur secondary to the indirect effects of a malignancy and occur remotely to the primary malignancy. Symptoms are mediated by cytokines, hormones or immune cross-reactivity. These syndromes can cause a diverse range of symptoms and can affect multiple systems.