Radiology Library

Radiology Library

A structured reference layer for radiology: landmark evidence with the practice it changed, classifications and staging systems as revision-first tables, and quick-reference packages of signs, numbers, devices and complications. Every entry cites its source and carries a review date.

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Landmark Evidence

• DAWN: Thrombectomy 6–24 Hours After StrokeInterventional Radiology

  DAWN established the benefit of mechanical thrombectomy 6–24 hours after last known well in highly selected patients with anterior-circulation large-vessel occlusion and clinical-core mismatch.

• SAMMPRIS (2011): Intracranial Stenting versus Aggressive Medical ManagementInterventional Radiology

  SAMMPRIS compared aggressive medical management alone with Wingspan intracranial stenting plus the same medical therapy in patients with recently symptomatic severe intracranial atherosclerotic stenosis.

• ARUBA (2014): Medical Management versus Intervention for Unruptured Brain AVMsInterventional Radiology

  ARUBA compared medical management alone with medical management plus interventional therapy for adults with unruptured brain arteriovenous malformations. It found a lower short-to-medium-term risk of death or symptomatic stroke with medical management.

• DEFUSE 3 (2018): Perfusion-Selected Thrombectomy at 6–16 HoursInterventional Radiology

  DEFUSE 3 established the benefit of mechanical thrombectomy 6–16 hours after last known well in selected anterior-circulation large-vessel occlusion with a favourable perfusion-mismatch profile.

• ISAT (2002): Endovascular Coiling versus Neurosurgical Clipping for Ruptured Intracranial AneurysmsInterventional Radiology

  Landmark randomised comparison of endovascular coiling and neurosurgical clipping for ruptured intracranial aneurysms judged suitable for either treatment.

Classifications

• BCLC Staging for Hepatocellular Carcinoma: 2026 UpdateGastrointestinal and Hepatobiliary

  The Barcelona Clinic Liver Cancer staging system integrates HCC burden, liver function and cancer-related performance status to estimate prognosis and guide treatment strategy.

• BI-RADS Assessment CategoriesBreast

  American College of Radiology BI-RADS final assessment categories linking breast imaging findings with malignancy likelihood and management.

• LI-RADS CT/MRI Treatment Response Assessment v2024Gastrointestinal and Hepatobiliary

  LI-RADS CT/MRI Treatment Response Assessment v2024 provides separate lesion-level response algorithms for hepatocellular carcinoma treated with nonradiation- and radiation-based locoregional therapies.

• Modified Fisher Scale for Aneurysmal Subarachnoid HaemorrhageNeuroradiology

  CT-based grading of subarachnoid and intraventricular blood after aneurysmal subarachnoid haemorrhage, primarily used to stratify the risk of symptomatic cerebral vasospasm.

• ASITN/SIR Angiographic Collateral Flow GradingInterventional Radiology

  A five-grade digital subtraction angiography scale describing the speed and completeness of collateral filling of an ischaemic vascular territory.

• Balthazar CT Severity Index and Modified CT Severity IndexGastrointestinal and Hepatobiliary

  Side-by-side comparison of the original Balthazar CT Severity Index and Modified CT Severity Index for grading the morphological severity of acute pancreatitis.

• Barrow Classification of Carotid–Cavernous FistulasInterventional Radiology

  An anatomical–angiographic classification of carotid–cavernous fistulas according to whether the fistula is direct or dural and whether its arterial supply arises from the internal carotid artery, external carotid artery or both.

• Bismuth–Corlette Classification of Perihilar CholangiocarcinomaGastrointestinal and Hepatobiliary

  An anatomical classification of perihilar cholangiocarcinoma based on the longitudinal extent of tumour involvement within the hepatic duct confluence and right or left hepatic ducts.

• Borden classification of dural arteriovenous fistulasNeuroradiology

  A three-tier classification of cranial and spinal dural arteriovenous fistulas based on the site of venous drainage and the presence of cortical venous reflux.

• CEAP Classification of Chronic Venous DisordersInterventional Radiology

  The CEAP system describes chronic venous disorders according to clinical manifestations, aetiology, anatomical distribution and pathophysiology. This entry uses the 2020 revision.

• Child–Pugh ClassificationGastrointestinal and Hepatobiliary

  Classifies the severity of chronic liver disease using five clinical and laboratory parameters. It is commonly used to describe hepatic functional reserve and support prognostic, procedural and treatment decisions.

• Cho–Do Angiographic Classification of Arteriovenous MalformationsInterventional Radiology

  Angiographic classification of arteriovenous malformations according to shunt and nidus morphology, used to guide the embolisation approach. Although applicable to uterine and pelvic AVMs, it is not a classification of uterine artery origin or branching anatomy.

• CIRSE and SIR Bleeding-Risk Categories for Image-Guided ProceduresInterventional Radiology

  CIRSE and SIR procedure-associated bleeding-risk categories used to guide periprocedural haemostatic assessment and antithrombotic planning. The systems are not interchangeable: CIRSE uses three tiers, whereas the current SIR scheme uses two.

• Endoleak Types I–VInterventional Radiology

  Classification of persistent aneurysm-sac perfusion or pressurisation following endovascular aortic repair, based on the underlying source.

• FIGO leiomyoma subclassification (types 0-8)Obstetric and Gynaecological

  The FIGO three-tier system locating uterine leiomyomas as types 0-8 by their relationship to the endometrium and serosa, used to standardise reporting and guide hysteroscopic, surgical and interventional treatment selection.

• Heidelberg Bleeding ClassificationNeuroradiology

  A combined radiological–clinical system for classifying intracranial haemorrhage after ischaemic stroke reperfusion therapy, extending ECASS by adding remote, intraventricular, subarachnoid and subdural bleeding categories and symptomatic/asymptomatic criteria.

• Hinchey Classification of Acute DiverticulitisGastrointestinal and Hepatobiliary

  Grades the anatomical severity of acute diverticulitis from localised inflammation or abscess formation to generalised purulent or faecal peritonitis.

• ISSVA Classification of Vascular Anomalies (2025)Interventional Radiology

  The 2025 ISSVA classification separates vascular anomalies into vascular tumours, vascular malformations and potentially unique vascular anomalies, with malformations further organised by flow characteristics and involved vascular channels.

• Koos Grading of Vestibular SchwannomaNeuroradiology

  A four-grade anatomical classification of vestibular schwannoma based on internal auditory canal confinement, cerebellopontine angle extension and brainstem mass effect.

• Krenning score: somatostatin receptor uptake gradingNuclear Medicine

  A five-grade visual scale of tumour somatostatin receptor uptake on 111In-pentetreotide scintigraphy, used historically to select patients for peptide receptor radionuclide therapy.

• Lawton–Young supplementary AVM grading systemNeuroradiology

  A three-variable supplementary grading scale (age, haemorrhagic presentation, nidus diffuseness) added to the Spetzler–Martin grade to give a supplemented Spetzler–Martin score that better predicts neurological outcome after brain AVM resection.

• Lung-RADS v2022: assessment categories and managementChest

  The ACR Lung-RADS v2022 structured reporting system for low-dose CT lung cancer screening, linking nodule size and attenuation to malignancy risk and a defined management step.

• MELD Score (Model for End-Stage Liver Disease)Gastrointestinal and Hepatobiliary

  An objective prognostic score estimating 90-day mortality in advanced liver disease and determining medical urgency for liver transplantation. MELD 3.0 is the current OPTN formulation.

• Meyerding grading of spondylolisthesisMusculoskeletal

  Radiographic grading of anterior vertebral slip expressed as the percentage translation of the superior vertebral body over the vertebra below, graded I to V.

• Modified Bell staging of necrotising enterocolitisPaediatric Radiology

  Clinical–radiological staging of neonatal necrotising enterocolitis from suspected disease to advanced disease with intestinal perforation.

• Modified CIRSE Classification of ComplicationsInterventional Radiology

  Grades complications of image-guided procedures according to procedural completion, additional treatment, hospitalisation, permanent sequelae and death.

• mRECIST for hepatocellular carcinomaGastrointestinal and Hepatobiliary

  Modified RECIST for HCC measures only arterially enhancing (viable) tumour rather than overall lesion size, making it suitable for response assessment after locoregional and systemic therapy.

• Papile and Volpe Grading of Germinal Matrix–Intraventricular HaemorrhagePaediatric Radiology

  Comparison of the historical Papile classification and the cranial ultrasound-based Volpe grading system for germinal matrix–intraventricular haemorrhage in preterm neonates.

• PI-RADS v2.1: Prostate MRI assessment categoriesGenitourinary

  Zone-specific scoring system for multiparametric prostate MRI that assigns an overall assessment category 1-5 reflecting the likelihood of clinically significant prostate cancer.

• Placenta Accreta Spectrum: Ultrasound and MRI DescriptorsObstetric and Gynaecological

  Consensus imaging descriptors for suspected placenta accreta spectrum on ultrasound and MRI, designed for standardised recognition and reporting rather than numerical scoring.

• Posterior Circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS)Neuroradiology

  A 10-point topographic score quantifying early ischaemic change within the posterior circulation, with additional weighting for the pons and midbrain.

• RENAL nephrometry score for renal massesGenitourinary

  A standardised CT/MRI scoring system that quantifies renal mass anatomy across five components and stratifies tumours into low, moderate and high anatomical complexity.

• Rotterdam CT score for traumatic brain injuryEmergency and Trauma

  A six-point admission CT score for predicting six-month mortality in moderate to severe traumatic brain injury, developed as a successor to the Marshall classification.

• Rutherford classification: acute and chronic limb ischaemia categoriesInterventional Radiology

  The Rutherford SVS/ISCVS reporting standards classify acute limb ischaemia into categories I, IIa, IIb and III by sensory loss, motor deficit and Doppler signals, and chronic lower-limb ischaemia into grades 0-III with categories 0-6 from asymptomatic disease to major tissue loss.

• Sarnat staging of neonatal hypoxic–ischaemic encephalopathyPaediatric Radiology

  Clinical and electroencephalographic staging of neonatal encephalopathy into mild, moderate and severe categories. It supports early severity assessment and selection for further evaluation for therapeutic hypothermia.

• SIR Adverse-Event ClassificationInterventional Radiology

  The Society of Interventional Radiology classification grades procedural adverse events by the resulting escalation in care, from mild events to death.

• Society for Vascular Surgery Thoracic Aortic Landing ZonesInterventional Radiology

  An anatomical zoning system for describing the position of thoracic aortic endograft attachment and seal sites during TEVAR.

• Spetzler–Ponce Classification of Brain Arteriovenous MalformationsInterventional Radiology

  A three-tier simplification of the Spetzler–Martin grading system that groups brain arteriovenous malformations according to operative risk and broad management strategy.

• Stanford and DeBakey classifications of aortic dissectionCardiac and Vascular

  The two standard anatomical classifications of aortic dissection: Stanford (ascending involvement, management-linked) and DeBakey (entry site plus extent), with the crosswalk between them and the modern non-A non-B category.

• Todani Classification of Choledochal CystsGastrointestinal and Hepatobiliary

  An anatomical classification of congenital bile duct cysts based on the site, extent and morphology of intrahepatic and extrahepatic biliary dilatation.

Quick Reference

• Abdominal Doppler and Elastography Physics EssentialsGastrointestinal and Hepatobiliary

  Protocol-first review of abdominal Doppler physics, artefact avoidance and quantitative elastography, covering insonation angle, aliasing, waveform criteria and Baveno-aligned liver stiffness thresholds.

• Acute Abdomen and Pelvic Emergency One-LinersEmergency and Trauma

  High-yield one-liners on emergency abdominal and pelvic imaging including bowel obstruction, perforation, appendicitis, mesenteric ischaemia and gynaecological emergencies.

• Acute Neuro and Spine Emergency One-LinersEmergency and Trauma

  High-yield one-liners on emergency neuroimaging for stroke, haemorrhage, herniation and acute spinal emergencies including trauma and cord compression.

• Bowel Ischaemia, Obstruction and Perforation EssentialsGastrointestinal and Hepatobiliary

  Core imaging signs of mechanical bowel obstruction, mesenteric ischaemia, and gastrointestinal perforation on radiography and CT.

• Chest and Cardiovascular Emergency One-LinersEmergency and Trauma

  High-yield one-liners on emergency chest and cardiovascular imaging including pulmonary embolism, aortic syndromes, pneumothorax and cardiac emergencies.

• Conventional Scintigraphy One-LinersNuclear Medicine

  High-yield, rapid-revision one-liners covering conventional nuclear medicine scintigraphy, including bone, renal, hepatobiliary, thyroid, and bleeding scans.

• Emergency CT Protocol and Dose One-LinersEmergency and Trauma

  High-yield one-liners on emergency CT acquisition protocols, contrast timing, radiation dose metrics and dose-reduction strategies in trauma and emergency imaging.

• Emergency Ultrasound and Point-of-Care Imaging One-LinersEmergency and Trauma

  High-yield one-liners on emergency and point-of-care ultrasound including eFAST, RUSH examination, biliary assessment and procedural guidance.

• Gamma Camera, SPECT and PET Physics One-LinersNuclear Medicine

  High-yield one-liners on gamma camera components, SPECT reconstruction, PET coincidence detection and key physics principles underlying nuclear medicine imaging.

• PET/CT and PET/MRI One-LinersNuclear Medicine

  High-yield one-liners on PET/CT and PET/MRI interpretation, physiological uptake patterns, common pitfalls and oncological applications.

• Polytrauma and Whole-Body CT One-LinersEmergency and Trauma

  High-yield one-liners on polytrauma imaging strategy, whole-body CT protocols, eFAST and key injury patterns encountered in emergency trauma radiology.

• Radiopharmaceuticals and Theranostics One-LinersNuclear Medicine

  High-yield one-liners on diagnostic radiopharmaceuticals, therapeutic radionuclides and the theranostic paradigm linking paired imaging and therapy agents.