Vertebral haemangiomas are the most common benign vertebral neoplasms. They are usually asymptomatic and incidentally detected due to their characteristic features on imaging for other reasons.
Please refer on the article on primary intraosseous haemangioma for a general discussion in this enti...
Differential diagnosis of vertebral lesions includes:
Lesion originating in vertebral body
vertebral body osteomyelitis
giant cell tumour
Langerhans cell histiocytosis
Vertebral metastases represent the secondary involvement of the vertebral spine by haematogenously-disseminated metastatic cells. They must be included in any differential diagnosis of a bone lesion in a patient older 40 years.
This article will focus only on the metastasis involving the bony s...
Vertebral pneumatocysts refers to the presence of a gas-filled cavity within the vertebrae, more prevalent on the cervical spine. Intraosseous pneumatocysts are more common adjacent to the sacroiliac joint while it is rare in the vertebral column. Other causes of vertebral gas e.g. Kümmell disea...
Vertebral scalloping is a concavity to the posterior (or less commonly anterior) aspect of the vertebral body when viewed in a lateral projection. A small amount of concavity is normal, as is concavity of the anterior vertebral body (see vertebral body squaring).
Vertebral vascular foramina are normal findings seen on cross-sectional imaging and should not be mistaken for a fracture, especially in the setting of trauma.
basivertebral veins (forms Hahn's canal): foramen is seen on the posterior surface of the vertebral body in the midline...
The vertebral venous plexus is a highly anastomotic network of valveless veins running along the entire length of the vertebral column from the foramen magnum to the sacral hiatus.
The vertebral venous plexus is comprised of three interconnected divisions:
internal vertebral ven...
Vertebra plana (a.k.a. pancake / silver dollar / coin-on-edge vertebra) is the term given when a vertebral body has lost almost its entire height anteriorly and posteriorly, representing a very advanced compression fracture. Plural is vertebrae planae. It can occur in a variety of settings, incl...
Mnemonics to remember the causes of vertebra plana include:
E: eosinophilic granuloma
T: trauma; tuberculosis
F: fracture (trauma)
E: eosinophilic granuloma
T: tumour (e.g. metastases, myelo...
C7, also called vertebra prominens, is the seventh cervical vertebra and looks like vertebrae C3-C6, but has some distinct features making it an atypical vertebrae. The name vertebra prominens arises from its long spinous process, which is easily palpable.
C7 possesses the stand...
Vertebroplasty is an imaging-guided procedure which entails percutaneous injection of surgical polymethylmethacrylate (PMMA) cement into a diseased vertebral body. Vertebroplasty provides pain relief and strengthening of the bone of vertebrae weakened by disease.
It can be used as ...
The vertex is the midline bony landmark at the most superior part of the calvaria in the standard anatomical position, near the midpoint of the sagittal suture (i.e. between the bregma and lambda).
It is one of the skull landmarks, craniometric points for radiological or anthropological skull m...
Vertical-banded gastroplasty (VBG) is an older, purely restrictive procedure used to treat morbid obesity.
It involves creating a small gastric pouch, based on the lesser curvature of the stomach (which is thicker and less resistant to stretching than the greater curvature), by using...
The vertical fissure line commences in or near the costodiaphragmatic recess and heads superomedially towards the hilum and terminates before or at the horizontal fissure. More commonly occurs on the right and may indicate partial volume loss of the lower lobe 1.
The vertical muscle of the tongue is one of the 4 intrinsic muscles of the tongue which alters the shape of the tongue mass, being entirely confined to the tongue without an attachment outside the tongue (like the extrinsic muscles of the tongue).
The muscles fibres attach proxim...
Very bizarre generalised lesions of bone tend to make you exclaim "Oh my! What is going here?" Although there are numerous potential causes, in this situation it is worth thinking of a number of entities:
skeletal dysplasias and metabolic diseases
Vesico-urachal diverticulum is one of the congenital urachal remnant abnormalities.
It is the proximal equivalent of a urachal umbilical sinus, representing a result of the failure of the urachus to close at the urinary bladder, forming an out-pouching of variable length from the...
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine from the bladder into the upper urinary tract and is typically a problem encountered in young children.
For grading of vesicoureteric reflux, please refer to vesicoureteric reflux grading.
The incidence of UTI is...
Vesicoureteric reflux (VUR) grading divides vesicoureteric reflux according to the height of reflux up the ureters and degree of dilatation of the ureters:
grade 1: reflux limited to the ureter
grade 2: reflux up to the renal pelvis
grade 3: mild dilatation of ureter and pelvicalyceal system
Vesico-vaginal fistulas are abnormal fistulous connections between the urinary bladder and vagina, resulting in an involuntary discharge of urine through the vagina.
The overall incidence of vesicovaginal fistula is unknown but was reported to be 2.11 per 100 births in Nigeria 1.
Vesicovaginal reflux is a well-known entity rarely encountered by radiologists. It is a behavioural disorder, a type of dysfunctional elimination syndrome commonly encountered in pre-pubertal girls. It is defined as reflux of urine into the vaginal vault either in supine or upright position duri...
The vestibular aqueduct is a structure of the inner ear being part of the osseous labyrinth. It contains the endolymphatic duct and sac. It normally has a diameter of ~1.5 mm (similar to the posterior semicircular canal) and runs from the vestibule in a transverse direction to the long axis of t...
The vestibular line of Lapayowker refers to a vertical line passing down the most lateral aspect of vestibular apparatus. The petrous part of internal carotid artery lies medial to this line but lies lateral to it in the case of an aberrant internal carotid artery which is the characteristic ang...
The vestibule is an approximately 4 mm central chamber of the bony labyrinth. It is dominated by depressions housing the:
utricle (elliptical recess)
saccule (spherical recess)
basal end of the cochlear duct (cochlear recess)
The cribrose areas have perforations through which the nerve bundl...
The vestibulocochlear nerve is the eighth cranial nerve and has two roles:
innervation to the cochlea for hearing
innervation to the vestibule for acceleration sense
It emerges between the pons and the medulla, lateral to the facial nerve and nervus intermedius, passing lateral...
Vicarious contrast material excretion (VCME) defines excretion of water-soluble contrast material in a way other than via normal renal secretion.
The most common vicarious excretion of water-soluble contrast material is via the liver, resulting in increased bile density seen in the gallbladder...
Vickers ligament is a ligamentous structure connecting the lunate bone and TFCC to the distal radius and is seen in the vast majority of patients with Madelung deformity 1.
Release of this thickened ligament may help in improving symptoms associated with Madelung deformity 2.
Video files are useful in a limited number of situations, but should NOT be used for routine stacks of scrollable images (such as CT or MRI). The reasons to use video include:
ultrasound cine clips
some dynamic barium studies
At present video support is limited.
Currently the ...
There are two arteries passing through Vidian canal from the pterygopalatine fossa to the petrous portion of the ICA. One is a branch of the internal maxillary artery (itself a branch of the ECA) and the other is from the C2 segment of the ICA. It therefore forms one of the ICA to ECA anastamoses.
Vidian nerve, also known as the nerve of the pterygoid canal or nerve of the Vidian canal, is so named because of the canal in which is travels: the Vidian canal.
It is formed by the confluence of two nerves:
greater superfical petrosal nerve (from the geniculate ganglion of the facial nerve) ...
The viking helmet appearance refers to the lateral ventricles in coronal projection in patients with dysgenesis of the corpus callosum. The cingulate gyrus is everted into narrowed and elongated frontal horns.
An alternative name is moose head appearance.
Vimentin is a fairly widespread cytoskeletal component encoding for intermediate filaments. It can be used as a target for immunohistochemistry to help characterise numerous tissues and tumours.
VIPomas are a very rare pancreatic endocrine tumour that classically presents with watery diarrhoea and hypokalaemia. These tumours secrete, and get their name from, vasoactive intestinal peptide (VIP).
VIPomas represent <2% of pancreatic endocrine tumours 2.
Viral bronchiolitis refers to a bronchiolitis secondary to viral aetiology.
Viral infection of airways resulting in inflammation and peribronchial oedema. Can then result in small airways occlusion which is the basis of hyperinflation and subsegmental atelectasis. Children more susce...
Viral encephalitides are the result of the brain parenchyma infection by a number of different viruses, many of which have similar presentations and imaging features. Specific diagnosis often requires PCR.
For viral infection of the meninges, please refer to the general article on viral mening...
Viral meningitides correspond to a relatively common and self-limited type of CNS infection clinically diagnosed based on the cerebrospinal fluid analysis and proportionally more frequent in young children than adults. Enteroviruses represent nowadays the most common cause of viral meningitis fo...
Viral respiratory tract infection is a broad term given to pulmonary infection from various viral agents.
They can be caused by any of a large number of viral agents, including but not limited to:
H1N1 pneumonia (swine influenza)
Virchow triad refers to the factors which can promote thrombosis, and are useful when thinking about the possible causes in a particular situation. They are:
factor V Laden deficiency
protein S deficiency
protein C deficiency
antithrombin III def...
Visceral artery aneurysms (VAA) are abnormal focal dilatations of arteries supplying an organ in the abdomen. VAAs include both true and pseudoaneurysms.
With different clinical manifestations and a more characteristic pathology, the renal artery aneurysms are discussed separately.
Visceral pleural invasion is a feature that can be seen in lung cancers. It is defined as tumour extension beyond the elastic layer of the visceral pleura. It is considered an aggressive sign and one of the most important adverse prognostic factors in non-small cell lung cancers 1.
The visceral space is one of the infrahyoid deep spaces of the head and neck.
The visceral space extends from the hyoid bone to the superior mediastinum (level of aortic arch / T4), and is surrounded by the middle layers of the deep cervical fascia.
The visibility of cases and playlists can be controlled by contributing author.
Public cases and public playlists are visible to all visitors to Radiopaedia.org and are indexed by search engines. Public cases are also returned as search results within Radiopaedia.org.
Unlisted cases and unlis...
Visual agnosia is a special type of agnosia where patients are unable to recognize objects despite having knowledge about them and being able to visually perceive them.
It typically occurs when there is damage to the ventral occipito-temporal pathway, such as in posterior cerebral atrophy (Bens...
Visual hallucinations are relatively uncommon, and can be due to a variety of 'organic' brain diseases, affecting a variety of regions of the brain. The use of the term organic here is by convention, and should not be taken to imply absence of brain dysfunction in psychiatric illness
Visual pathway deficits are determined by the location of the lesion or pathology. Understanding of the visual system is paramount and provided the globe is normal, the field defects can be defined from anterior to posterior as:
unilateral central scotoma
The visual system transmits visual information from the retina within the eyes to the primary visual cortex of the occipital lobe as well as the pretectal nuclei and superior colliculi of the midbrain.
Below the visual pathway is described from distal to proximal in a single hemi...
Vitamin A (the retinoids) are a group of fat soluble vitamins required for many physiological functions, mainly vision, reproduction and epithelial maintenance. In the retina, a specific retinoid 11-cis-retinal is formed by photo-isomerisation within the rods and cones.
Vitamin B1 (thiamine) is a water soluble vitamin that is an important coenzyme for two reactions in the citric acid cycle (Kreb’s cycle). It therefore is vital for cellular ATP production, particularly in the central nervous system.
Pathological manifestations only occur with...
Vitamin B12 (cobalamin) is a water soluble vitamin synthesised by intestinal flora that forms a cobalt-based coenzyme that is required for two vital cellular reactions, namely the production of methionine (an amino acid) and the metabolism of odd-number carbon atom fatty acids.
Vitamin B2 (riboflavin) is a water soluble vitamin that is an important component of the cofactors FAD and FMN. The flavoproteins contribute to many cellular reactions, including the metabolism of several other vitamins.
Deficiency is not reported but may be present with deficiencies of other ...
Vitamin B3 (niacin or nicotinic acid) is a water soluble vitamin that is an important part of the coenzyme nicotinamide adenine dinucleotide (NAD+) which is involved in many reactions of cellular metabolism.
Pathological manifestation occur in niacin deficiency known as pella...
Vitamin B5 (panthothenic acid) is a water soluble vitamin that is required to synthesise coenzyme A, a very important coenzyme in many reactions of cellular metabolism. Deficiency is not well characterised.
Vitamin B6 is a group water soluble vitamins that are deratives of pyridine, namely pyridoxine, pyridoxal and pyridoxamine. All three form part of the coenzyme pyridoxal 5'-phosphate (PLP) which is involved many cellular reaction including the synthesis of several amino acids and the metabolism ...
Vitamin B7 (biotin) is a water soluble vitamin that is a coenzyme for many reactions, including gluconeogenesis and the synthesis of fatty acids and amino acids.
Biotin deficiency is caused by dietary insufficiency, pharmacological interactions and, possibly, increased biotinolysis in smokers a...
Vitamin B9 (folate or folic acid) is a water soluble vitamin that is vital for the synthesis of several amino acids, the purines adenosine and guanine and the pyrimidine thymine (three of the four nucleotide bases and hence critical for the synthesis of nucleic acids.)
The antimicrobial group s...
Vitamin C (ascorbic acid) is a water soluble vitamin that is a coenzyme for the formation of the structure protein collagen, particularly creating cross-linking of collagen fibres which greatly increases its tensile strength. It also acts as an antioxidant.
Vitamin D is used to describe a group of five fat-soluble secosteroid vitamins required for the homeostasis of serum calcium and phosphorus. Vitamin D is a prohormone that exists in two forms in humans (D2 and D3).
Cholecalciferol (D3) acts by regulating calcium and phosphorus intestinal absorp...
Vitamin E (the tocopherols) are a group of fat-soluble vitamins that act as an antioxidant. Hypovitaminosis E is rarely seen outside premature infants. Hypervitaminosis E is extremely rare as vitamin E is the least toxic of all the vitamins.
Vitamin K (phylloquinone (K1) and menaquinone (K2)) are a group of fat-soluble vitamins essential for normal blood-clotting function. Menaquinone is synthesised by normal flora in the intestine although the amount produced in vivo in the human gut is likely negligible. Vitamin K serves as a coen...
Vitamins are a group of organic compounds used in biochemical pathways. Many are components of coenzymes in particular metabolic reactions. Vitamins are generally not synthesised by the human body and hence must be acquired through the diet.
In radiology, there are some imaging manifestations o...
Vitreous haemorrhage refers to bleeding into the vitreous chamber.
Vitreous haemorrhage has an incidence of approximately 7 in 100000 1,2.
The most common clinical presentation is with sudden, painless visual loss to varying degrees of severity 2. There may b...
Viva preparation is key to successful completion of professional exams. It is really important to think about the types of cases that you will be shown in the viva and preparing aurally for them.
So, rather than learning sitting with your books, get a set of films, or using the Radiopaedia.org...
Viva technique is hugely important when sitting oral examinations. You must remember that the examiners may well have been examining for several days and for hours at a time. They will have shown their films many times and will know them backwards! Moreover, their films will be beloved, so do no...
Vocal cord paralysis/palsy (VCP) can cause laryngeal dysfunction ranging from slight hoarseness to life-threatening airway obstruction.
Left vocal cord paralysis is twice as common than right vocal cord paralysis, and unilateral vocal cord paralysis much less common than bilateral vo...
Vogt-Koyanagi-Harada syndrome is a multisystem disorder characterised by granulomatous panuveitis with exudative retinal detachments that is often associated with neurologic and cutaneous manifestations.
Vogt-Koyanagi-Harada usually affected those of Asian, Middle Eastern, Asian I...
Voiding cystourethrography (VCUG), also known as a micturating cystourethrography (MCU), is a fluoroscopic study of the lower urinary tract in which contrast is introduced into the bladder via a catheter. The purpose of the examination is to assess the bladder, urethra, postoperative anatomy an...
Volar intercalated segmental instability (VISI) is a type of instability involving the wrist. It is less often encountered than dorsal intercalated segmental instability (DISI).
It presents in most cases with nonspecific wrist pain and a "clunking" on the ulnar deviation ...
Volar plate avulsion injuries are a type of avulsion injury. The volar plate of the proximal interphalangeal (PIP) joint is vulnerable to hyperextension injury, in the form of either a ligament tear or an intra-articular fracture.
The volar plate forms the floor of PIP joint sepa...
Voltage gated potassium channel (VGKC) antibody encephalitis is an autoimmune encephalitis with antibodies against the voltage gated potassium channel. It is one of the most common forms of autoimmune limbic encephalitis in the absence of primary extra-CNS tumours. Autoimmune VGKC encephalitis c...
The vomer is one of the facial bones and forms the postero-inferior part of the bony nasal septum.
Occasionally the sphenoid sinus may pneumatise the vomer 2.
Von Hippel-Lindau (vHL) disease is characterised by the development of numerous benign and malignant tumours in different organs (at least 40 types 1) due to mutations in the VHL tumour suppressor gene on chromosome 3.
The disease is rare with an estimated prevalence of 1:35,000-5...
Von Willebrand disease (vWD) is the most common inherited bleeding diathesis (easy bleeding).
Bruising and mucosal bleeding are typical presentations, but there is a spectrum of severity. The more residual vWF a patient has, the less severe the bleeding.
Voxel is a contraction of the words 'volume' and 'element' and was coined as a 3-D equivalent of a pixel. It is an individual point in space on a 3-dimensional, regular matrix. The location of each voxel is encoded by its relative relationship to other voxels.
A tensor is a voxel that contains ...
V/Q (ventilation/perfusion) scan is a scintigraphic examination of the lung that evaluates pulmonary vasculature perfusion and segmental bronchoalveolar tree ventilation.
diagnosis of suspected pulmonary embolism (PE)
monitor pulmonary function following lung transplant
Staging of vulval cancer is the FIGO staging system and is as follows:
stage 0: carcinoma in situ (pre-invasive); corresponds to Tis
stage I: tumour <2cm (greatest dimension) and confined to vulva/perineum; corresponds to T1
stage Ia: stromal invasion by <1mm
Stage Ib: stromal invasion by >1...
Vulval neoplasms are rare and mostly seen in an elderly female patients. Squamous cell carcinoma is most common malignancy of the vulva which only 30% of them are associated with oncogenic HPV viruses.
Squamous neoplastic lesions
classic vulvar intraepithelial neopla...
Waardenburg syndrome is a rare congenital pigmentary disorder secondary to an abnormal distribution of neural crest-derived melanocytes during embryogenesis resulting in patchy areas of depigmentation. It is considered in the investigation of congenital sensorineural deafness.
Wackenheims line (also known as the clivus canal line or basilar line) is formed by drawing a line along the clivus and extending it inferiorly to the upper cervical canal.
Normally the tip of the dens is ventral and tangential to this line. In basilar invagination odontoid process transects th...
The WAGR syndrome stands for:
Wilms tumours (greatly increased risk)
Occurs from a mutation related to chromosome 11p13 3 which is in close proximity to WT1 gene.
A Wagstaffe-Le Forte fracture refers to an avulsion fracture of the medial aspect of the distal fibula due to avulsion of the anterior tibiofibular ligament attachment.
lower extremity fractures
Waldenström sign is the increased distance between the pelvic tear drop and the femoral head. It is a non-specific sign of hip joint effusion.
>11 mm total distance or >2 mm difference compared to contralateral hip 1, 2
measured between the lateral aspect of ...
Waldenström's macroglobulinaemia (WM), (previously also known as lymphoplasmacytic lymphoma (LPL)), is a type of B-cell lymphoma. It is a rare condition, accounting for only 1% of all lymphoproliferative disorders.
Recent publications classify Waldenström's macroglobulinaemia as an lymphoplasm...
Waldeyer's ring is a ring of lymphoid tissue located in the nasopharynx and oropharynx at the entrance to the aerodigestive tract.
The structures composing this ring are:
palatine tonsils (also called the faucial tonsils)
adenoid tonsils (nasopharyngeal tonsils)
the lateral ba...
Walker-Warburg syndrome (WWS), sometimes known as HARDE syndrome, is an extremely rare lethal form of congenital muscular dystrophy. It is primarily characterised by:
fetal hydrocephalus: almost always present
neuronal migrational anomalies: agyria (cobblestone lissencephaly / lissencephaly ty...
The walking man sign is seen on a lateral chest radiograph and is a sign of left atrial enlargement. It results from posterior displacement of the left main bronchus such that it no longer overlaps the right bronchus. The left and right bronchus thus appear as an inverted 'V', mimicking the legs...
The wall-echo-shadow sign (also known as WES sign) is an ultrasonographic finding within the gallbladder fossa referring to the appearance of a "wall-echo-shadow"
a curvilinear hyperechogenic line representing the gallbladder wall
a thin hypoechoic space representing a small amount of bile
Walled-off pancreatic necrosis (WOPN) is a late complication of acute pancreatitis, although it can occur in chronic pancreatitis or as a result of pancreatic trauma. Differentiation of WOPN from pancreatic pseudocyst is essential because management differs. WOPN may need aggressive treatment to...
Wallerian degeneration (WaD) is the process of antegrade degeneration of the axons and their accompanying myelin sheaths following proximal axonal or neuronal cell body lesions. It may result following neuronal loss due to cerebral infarction, trauma, necrosis, focal demyelination or haemorrhage...
Wandering spleen is a rare condition in which the spleen migrates from its usual anatomical position, commonly to the lower abdomen or pelvis.
Wandering spleen is rare, with a reported incidence of <0.5%.
Diagnosis is most commonly made between ages 20 and 40 and is more common i...
Ward triangle refers to a radiolucent area between principle compressive, secondary compressive and primary tensile trabeculae in the neck of femur.
It should be differentiated from Babcock triangle.
Wartenberg syndrome also known as cheiralgia paresthetica is due to compression of superficial branch of the radial nerve in the distal forearm. It can be secondary to tight watch band or handcuffs, compression from distal radius fracture or idiopathic.
Patients present ...
Warthin tumours, also known as lymphomatous papillary cystadenomas, are benign, sharply demarcated tumours of the salivary gland. They are of lymphoid origin and most commonly arise from parotid gland tail. They may be bilateral or multifocal in up to 20% of cases and are the most common neoplas...
The wasp-waist sign is a radiographic appearance seen in patients with Klippel Feil syndrome. It results from fusion of the vertebral bodies such that the anteroposterior diameter at the level of the affected discovertebral joint is smaller than the diameter at the superior and inferior limits o...