The IASLC (International Association for the Study of Lung Cancer) 8th edition lung cancer staging system was introduced in 2016 and supersedes the IASLC 7th edition.
It is as follows:
T: primary tumour
Tx: primary tumour cannot be assessed or tumour proven by the presence of mal...
In 2013, the 5th World Symposium on pulmonary hypertension took place in Nice, France and modified the classification system for pulmonary hypertension.
The modified system divides pulmonary hypertension into five groups:
group 1: pulmonary arterial hypertension (disorders of the pulmonary ar...
The several forms of osteogenesis imperfecta (OI) have been classified, representing wide variation in appearance and severity, and clinical features vary widely not only between types but within types.
OI was initially classified by type according to a scheme developed by Dr Da...
Facial fractures are commonly caused by blunt or penetrating trauma sustained during motor vehicle accidents, assaults, and falls. The facial bones are thin and relatively fragile making them susceptible to injury.
Males are affected more commonly than females and facial fractures...
Benign renal tumours were histologically classified according to the WHO in 2004 as follows 1:
Renal cell tumours
renal papillary adenoma - renal adenoma
metanephric adenoma of kidney
metanephric adenofibroma of kidney
metanephric stromal tumour of kid...
There are a bewildering number of bone tumours with a wide variety of radiological appearances:
bone island / enostosis
Le Fort fractures are fractures of the midface, which collectively involve separation of all or a portion of the midface from the skull base. In order to be separated from the skull base, the pterygoid plates of the sphenoid bone need to be involved as these connect the midface to the sphenoid b...
The WHO classification of CNS tumours is the most widely accepted system for classifying CNS tumours and was based on the histological characteristics of the tumour. Although the most recent version of the 'blue book' is the 4th edition from 2007, an update has been released in 2016 3, which sho...
Congenital cardiovascular anomalies are relatively common, with an incidence of up to 1% if small muscular VSDs are included. As a group, there is a much greater frequency in syndromic infants and in those that are stillborn.
Broadly, congenital cardiovascular anomalies ...
Chronic suppurative lung disease (CSLD) refers to a group of conditions which includes:
primary ciliary dyskinesia
This term is usually used in the context of paediatric patients.
The AO classification of subaxial injuries aims to simplify and universalise the classification of subaxial cervical spine fractures and improve interobserver and intraobserver reliability.
The AO subaxial cervical spine injury classification involves four criteria based on morphology, facet in...
There are several classification systems for sacral fractures, but the most commonly employed are the Denis classification and subclassification systems, and the Isler classification system. These classification systems are important to understand as proper classification can impact management.
The AO classification of sacral injuries aims to simplify and universalise the process of classifying sacral injuries and improve interobserver and intraobserver reliability.
The AO sacral classification is broken into three subsections that follow a hierarchical structure similar to the AO cla...
The three column concept of thoracolumbar spinal fractures was initially devised by Francis Denis and presently CT is mandatory for an accurate classification.
While initially developed for classification of thoracolumbar spinal fractures, it can also be applied to the lower cervical spine 3 as...
A retropulsed fragment is any vertebral fracture fragment that is displaced into the spinal canal, thereby potentially causing spinal cord injury.
They usually arise from the vertebral body with or without a portion of the pedicle, and are displaced posteriorly, hence the prefix 'retro'.
Coronary Artery Disease - Reporting and Data System (CAD-RADSTM) classification is proposed by the Society for Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR), and the North American Society for Cardiovascular Imaging (NASCI), last updated in 2016.
The Lund-Mackay score is a widely used method for radiologic staging of chronic rhinosinusitis 1.
When reading a CT scan of the paranasal sinuses and ostiomeatal complex, the reader assigns each sinus a score of:
0 (no abnormality)
1 (partial opacification) or
2 (complete opacification)
Kuhn classification is an anatomical classification for the subtypes of frontal cells.
type 1 (~37%): a single air cell above the agger nasi cell
type 2 (~19%): two or more air cells above the agger nasi cell
type 3 (~7%): a single large cell above the agger nasi cell that extends into the fr...
Mammographic density is considered a risk factor for breast cancer, and parenchymal patterns in breast imaging are important in the way in which the effects mammographic screening sensitivity. Women with high-risk density patterns should be screened more frequently and/or with additional views p...
BI-RADS classification is proposed by the American College of Radiology (ACR), last updated in November 2015, and is a widely used classification system at the time of writing this article (July 2016).
The BI-RADS acronym stands for Breast Imaging-Reporting and Data System which is a widely acc...
PI-RADS (Prostate Imaging Reporting and Data System) refers to a structured reporting scheme for evaluating the prostate for prostate cancer. It is designed to be used in a pre-therapy patient.
The original PI-RADS score was annotated, revised and published as the second version, PI-RADS v2 6, ...
BI-RADS VI is a new addition to the ACR (American College of Radiology) BI-RAD system. The prior classification system was a 5-tier system. The current system is a 6-tier system.
According to the current BI-RADS tier, patients with biopsy proven cancer prior to definitive therapy would be categ...
The 5-tier ACR system was a previously used system for classification of radiologic breast findings, proposed by the American College of Radiology (ACR). It is no longer in widespread use, having been gradually superseded by the 6-tier BI-RADS classification system first published in 1992.
ACR TI-RADS is a reporting system for thyroid nodules on ultrasound proposed by the American College of Radiology (ACR) 1.
This uses a standardised scoring system for reports providing users with recommendations for when to use fine needle aspiration (FNA) or ultrasound follow-up of suspicious ...
The Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification of thoracolumbar injuries aims to simplify and universalise the process of classifying spinal injuries and improve interobserver and intraobserver reliability 3.
The AOSpine thoracolumbar classification system consists of only ...
Open book pelvic injuries are most often the result of high-energy trauma and are associated with significant morbidity and mortality due to associated vascular injuries.
Open book pelvic injuries result from an anteroposterior compression injury to the pelvis and result in a combin...
Necrotising enterocolitis (NEC) can be staged into three groups, helping to guide appropriate treatment. In general, stage I and II are managed medically whereas stage III is managed surgically.
lethargy, temperature instability, apnoea, bradycardia
emesis, abdominal d...
Following months of preparation, experts in the field of vasculitis from 12 different countries proposed an update to the 1994 International Chapel Hill Consensus Conference nomenclature of vasculitides. This 2012 update at the time of writing (mid-2016) remains the most widely used system for d...
T staging of oropharyngeal tumours is as follows:
The oropharynx includes the base of the tongue, the inferior surface of the soft palate and uvula, the anterior and posterior tonsillar pillars, the glossotonsillar sulci, the pharyngeal tonsils, and the lateral and posterior pharyng...
The Kellgren and Lawrence system is a common method of classifying the severity of knee osteoarthritis (OA) using five grades 1. This classification was proposed by Kellgren et al. in 1957 2 and later accepted by WHO in 1961.
In applying the system, the prevalence of chronic knee pain in a post...
The Alberta stroke programme early CT score (ASPECTS) 1 is a 10-point quantitative topographic CT scan score used in patients with middle cerebral artery stroke. It has also been adapted for the posterior circulation (see below).
Segmental assessment of the MCA vascular territo...
The Rockwood classification (1998) is the most common classification system in use for acromioclavicular joint injuries 3. This well known 6-type system is a modification of the earlier 3-class classification system described by Allman (1967) 2 and Tossy (1963).
It takes into account not only t...
The Gustilo Anderson classification, sometimes referred to as the Gustilo classification is the most widely accepted classification system of open (or compound) fractures.
The grading system is used to guide management of compound fractures, with higher grade injuries associated with higher ris...
The 2015 International Panel for NMO Diagnosis criteria are, as the name implies, a set of criteria used to diagnose neuromyelitis optic spectrum disorder (NMOSD) 1. They are based on a combination of clinical, laboratory, and neuroimaging findings.
Diagnostic criteria for NMOSD with ...
A commonly used classification scheme used by urologists and rehabilitation specialists, described by Wein, classifies bladder impairment following spinal cord injury according to the level of injury:
suprasacral (infrapontine) bladder - upper motor neuron lesion, releasing the sacral micturiti...
The Revised Atlanta classification of acute pancreatitis is an international multidisciplinary classification of the severity of acute pancreatitis, updating the 1991 Atlanta classification. It was initially revised in 2012 and then further updated in 2016 6.
The worldwide consensus aims for an...
Abdominal hernias (herniae also used) may be congenital or acquired and come with varying eponyms. They are distinguished primarily based on location and content. 75-80% of all hernias are inguinal.
Content of the hernia is variable, and may include:
small bowel loops
mobile colon segments (s...
There are several thoracolumbar spinal fracture classification systems:
AO classification of thoracolumbar injuries
three column concept of thoracolumbar spinal fractures (Denis classification)
thoracolumbar injury classification and severity scor...
This is a basic article for medical students and other non-radiologists
Distal fibula fractures are the most common type at the ankle and are usually the result of an inversion injury with or without rotation. They are the extension of a lateral collateral ligament injury.
The ISSVA classification of vascular anomalies is based on the initial classification published by Mulliken and Glowacki in 1982, and encompasses all vascular malformations and tumours in a framework of internationally consistent nomenclature. The classification was revised in 2014.
It is proba...
Cochlear anomalies are a variety of congenital anomalies which, depending on the exact time at which an insult occurs during embryogenesis, may have different manifestations. Terminology is often used imprecisely leading to confusion not only among clinicians, but also in the literature.
The American Association for the Surgery of Trauma (AAST) renal injury scale 1,6 is the most widely used grading system for renal trauma at the time of writing (late 2016). Severity is assessed according to the depth of renal parenchymal damage and involvement of the urinary collecting system a...
The ultrasound "U" classification of thyroid nodules has been developed by the British Thyroid Association (BTA) as part of their 2014 guidelines on the management of thyroid cancer 1.
It allows for stratifying thyroid nodules as benign, suspicious or malignant based on ultrasound appearances t...
The International Ovarian Tumour Analysis (IOTA) group ultrasound rules for ovarian masses are a simple set of ultrasound findings that classify ovarian masses into benign, malignant or inconclusive masses. These rules apply to masses that are not a classical ovarian mass (e.g. corpus luteum, en...
The Tanaka criteria, also referred to as the Fukuoka consensus guidelines, is a classification system for intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs).
The prior international consensus guidelines (2006) were referred to as the Sendai criteria, which la...
The WHO grading system is the most widely used system for grading diffuse astrocytomas (at the time of writing i.e. mid-2016) and is an adaptation of the now superseded St Anne-Mayo grading system (also known as the Daumas-Duport grading system).
Grade I is reserved for localised astrocytomas...
The modified Fisher scale is a method for grading subarachnoid haemorrhage (SAH) seen on non-contrast CT. It was developed from the original Fisher scale which was modified to account for patients with thick cisternal blood and concomitant intraventricular (IVH) or intraparenchymal haemorrhage.
TI-RADS is a risk stratification system for classifying thyroid lesions and was recently recognized in an American College of Radiology (ACR) white paper1. Its use is being advocated similar to BI-RADS category for breast lesions.
In 2017, a white paper2 was released by the ACR committee on th...
The Castellvi classification is used for lumbosacral transitional vertebra (LSTV):
type I: enlarged and dysplastic transverse (at least 19 mm)
type II: pseudoarticulation of the transverse process and sacrum with incomplete lumbarisation/sacralisation; enlargemen...
The Risser classification is used to grade skeletal maturity based on the level of ossification and fusion of the iliac crest apophyses. It is primarily in planning corrective surgery for scoliosis.
stage 0: no ossification center at the level of iliac crest apophysis
stage 1: ...
Classification system for malformations of cortical development organises a myriad of conditions into one of three major underlying groups according to the main underlying mechanism:
group I: abnormal cell proliferation or apoptosis
group II: abnormal neuronal migration
group III: abnormal co...
Along with the DeBakey classification, the Stanford classification is used to separate aortic dissections into those that need surgical repair, and those that usually require only medical management. The Stanford classification divides dissections by the most proximal involvement:
type A: A aff...
Anterior cruciate ligament (ACL) avulsion fracture or tibial eminence avulsion fracture is a type of avulsion fracture of the knee. This typically involves separation of the tibial attachment of the ACL to variable degrees. Separation at the femoral attachment is rare 5.
It is mor...
There are several drugs which are useful for evaluation of nuclear studies for respective systems. These drugs play an important role in monitoring the physiological changes and aiding in diagnosis .
Drugs used are
metoclopramide and erythromycin in gastrointestinal scintigraphy; used for gast...
There are specific terms used when describing a syrinx or other cystic lesions within the spinal cord 1:
hydromyelia: fluid accumulation/dilatation within the central canal, therefore, lined by ependyma
syringomyelia: cavitary lesion within cord parenchyma, of any cause (there are many); locat...
Cerebral vascular malformations encompass a large variety vascular lesions which differ in haemodynamics, structure and prognosis. Some can be life threatening (e.g. vein of Galen aneurysmal malformations, arteriovenous malformations) whilst others are almost always incidental and asymptomatic (...
There are numerous terms used in radiology that are worth knowing and this is list of some of them.
The medial temporal lobe atrophy (MTA) score is useful in distinguishing patients with mild cognitive impairment and Alzheimer disease from those without impairment 2 is helpful in the assessment of patients with possible dementia (see neurodegenerative MRI brain - an approach).
The magnetic resonance imaging in multiple sclerosis (MAGNIMS), which is a European collaborative research network, published in 2016 new recommendations to upgrade the imaging diagnosis criteria for multiple sclerosis (MS). These came as a consensus, based on evidence-based and expert opinions ...
Temporal bone fracture is usually a sequela of significant blunt head injury. In addition to potentially damage to hearing and the facial nerve, associated intracranial injuries, such as extra-axial haemorrhage, diffuse axonal injury and cerebral contusions are common. Early identification of te...
McDonald diagnostic criteria for multiple sclerosis are clinical, radiographic, and laboratory criteria used in the diagnosis of multiple sclerosis. They were originally introduced in 2001 1, revised in 2005 2, 2010 3, 2016 (by MAGNIMS) 4 and most recently in 2017 5. The 2017 revision is the foc...
Brainstem stroke syndromes, also known as crossed brainstem syndromes, refer to a group of syndromes that occur secondary to lesions, most commonly infarcts, of the brainstem.
Although many different brainstem stroke syndromes have been classically described, the majority appear e...
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.
occurs in ~5% (range 0.4-8%) of the ...
The WHO histological classification is a detailed classification of tumours of the uterine cervix.
squamous tumours and precursors
squamous cell carcinoma, not otherwise specified - 8070/3
keratinizing - 8071/3
non-keratinizing - 8072/3
basaloid - 8083/3
verrucous - 805...
The 2005 WHO histological classification of odontogenic tumours lays out a classification system for neoplasms and other tumours related to the odontogenic apparatus. At the time of writing (2016), it is still the most widely used classification system.
The Hunt and Hess scale describes the severity of subarachnoid haemorrhage, and is used as a predictor of survival.
asymptomatic or minimal headache and slight neck stiffness
moderate to severe headache; neck stiffness; no neurologic deficit except cranial nerve...
Spondylolisthesis is a denotes the slippage of one vertebra relative to the one below. Spondylolisthesis can occur anywhere but is most frequent, particularly when due to spondylolysis, at L5/S1 and to a lesser degree L4/5.
Although etymologically it is directionless (see below) a...
There are numerous causes of pulmonary hypertension, and thus not surprisingly there have been many classification systems.
In 2003, the 3rd World Symposium on PAH met in Venice and produced an updated classification system (this has been further revised in the Dana Point classification of pulm...
The classification system for pulmonary hypertension was revised at the 4th World Symposium on Pulmonary Hypertension held in Dana Point, California, in 2008 1.
This system is as follows:
group 1: pulmonary arterial hypertension
1.1: idiopathic pulmonary arterial hypertension
1.2: heritable ...
Ovarian cysts are commonly encountered in gynaecological imaging, and vary widely in aetiology, from physiologic, to complex benign, to neoplastic.
Small cystic ovarian structures should be considered normal ovarian follicles unless the patient is pre-pubertal, post-menopausal, pregnant, or the...
Odontoid process fracture, also known as the peg or dens fracture, occurs where there is a fracture through the odontoid process of C2.
The mechanism of injury is variable, and can occur both during flexion or extension with or without compression 5.
There are two cl...
Peripheral arterial disease (PAD) is a common and debilitating condition.
The age-adjusted prevalence of peripheral arterial disease is ~12% 3.
Atherosclerosis is the leading cause of occlusive arterial disease of the extremities in patients over 40 years of age with t...
The Edinburgh criteria were proposed in 2018 in order to diagnose lobar intracerebral haemorrhage associated with cerebral amyloid angiopathy (CAA) 1. They can potentially be used to rule CAA-associated lobar haemorrhage either in or out, but require external validation in other patient populati...
The Couinaud classification (pronounced kwee-NO) is currently the most widely used system to describe functional liver anatomy. It is the preferred anatomy classification system as it divides the liver into eight independent functional units (termed segments) rather than relying on the tradition...
The Müllerian duct anomaly classification is a seven point system that can be used to describe a number of embryonic Müllerian duct anomalies:
class I: uterine agenesis / uterine hypoplasia
a: vaginal (uterus: normal / variety of abnormal forms)
Orthoroentgenogram is a radiographic study used to evaluate anatomic leg length and calculate leg-length discrepancies. This study utilises a long ruler placed on the film, and three radiographs including bilateral hips, knees and ankles.
Similar studies used to evaluate true leg length include...
Non-specific interstitial pneumonia (NSIP) is the second most common morphological and pathological pattern of the interstitial lung diseases. NSIP has two main subtypes:
fibrotic type: most common, having a more dismal outcome
cellular type: less common, but carries a much better prognosis du...
Non-Hodgkin lymphoma (NHL) is a catch-all term for lymphomas that are not of the Hodgkin subtype. It is a heterogeneous group of malignancies in terms of histology, clinical presentation, and prognosis.
See 2008 WHO classification for further information on subtypes.
Myeloproliferative disorders (MPDs) are a diverse group of conditions that are characterised by the overproduction of red cells, white cells and/or platelets in bone marrow. There are numerous conditions considered in this group but the most common are:
Here is a list of some of the most useful differential diagnoses in musculoskeletal imaging.
lucent/lytic bone lesions (FEGNOMASHIC)
multiple lucent/lytic bone lesions
benign lytic bone lesions in patients under 30
diffuse bony sclerosis
permeative process in bone
Microtia refers to a small pinna of the ear, when is it completely absent it is termed anotia.
The estimated incidence at around 1:9000 live births. It is more common in males and there is a recognised right sided predilection.
Microtia can be associated ...
The combined conduit score (CCS) is a grading scheme for the assessment of the degree of transverse-sigmoid sinus stenosis in the setting of idiopathic intracranial hypertension. The score was initially developed for ATECO MR venography 1.
Assessment is performed using maximum inten...
The Krenning score is a proposed semi-quantitative method of assessing the degree of tracer uptake on octreotide scintigraphy.
Initially designed for assessment of 111In-DTPA on planar imaging, the Krenning score is applicable to SPECT or SPECT/CT using various radiopharmaceuticals....
The Raymond–Roy occlusion classification (RROC) is an angiographic classification scheme for grading the occlusion of endovascularly treated intracranial aneurysms 1. It is also known as the Raymond class, Montreal scale or the Raymond Montreal scale.
class I: complete obliteration
class II: r...
The shunt-dependency in symptomatic aneurysmal subarachnoid haemorrhage (SDASH) score is a harmonized score for the prediction of hydrocephalus requiring shunting after subarachnoid haemorrhage. The tool is employed in the acute phase to predict which patients will require shunting, rather than ...
Osteochondritis dissecans can be classified at surgery into 4 stages:
lesion in continuity with the host bone
covered by intact cartilage
stable on probing
partial discontinuity of the lesion from the host bone
unstable on probing
fragment not dislocat...
Hamburg classification system of vascular malformations is one of the more commonly used systems to describe the wide range of vascular malformations, largely replacing the many various eponymous syndromes traditionally used. It accounts for the underlying anatomical, histological, and pathophys...
The Galassi classification of middle cranial fossa arachnoid cysts is used to classify arachnoid cysts in the middle cranial fossa, which account for 50-60% of all arachnoid cysts 1. Galassi et al. published this classification in 1982, and at the time of writing (June 2016), it remains the most...
McDonald diagnostic criteria 2010 were MRI criteria used in the diagnosis of multiple sclerosis. They were introduced in 2001, revised in 2005, 2010 (the focus of this article) and in 2016 (by MAGNIMS) 1. The latest revision was in 2017 2.
Below are the previously used criteria, which should no...
The McDonald's criteria are MRI criteria used in the diagnosis of multiple sclerosis and were initially described in 2001 and revised in 2005. Since these initial revisions, the criteria has been revised again in 2010 and 2017.
Below are the previously used criteria, which should no longer be e...
The Harvard scoring system for rhinosinusitis is, as the name implies, a scoring system based on CT-scan assessment for grading of rhinosinusitis.
0: normal (< 2 mm mucosal thickening on any sinus wall)
1: all unilateral disease or anatomic abnormality
2: bilateral disease limited to...
The Glasgow Coma Scale (GCS) was developed in 1974 1 to describe the level of consciousness specifically in patients with head injury although it is now used widely as a shorthand for all manner of presentations and has generally been validated, although concerns remain about its use in certain ...
The Weber ankle fracture classification (or Danis-Weber classification) is a simple system for classification of lateral malleolar fractures, relating to the level of the fracture in relation to the ankle joint. It has a role in determining treatment.
below the level of...