Radiology ( ) is the medical discipline that uses medical imaging to diagnose diseases and guide their treatment, within the bodies of humans and other animals. It began with

radiography Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeu ...

(which is why its name has a root referring to radiation), but today it includes all imaging modalities, including those that use no electromagnetic radiation (such as

ultrasonography Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies fr ...

and magnetic resonance imaging), as well as others that do, such as computed tomography (CT),

fluoroscopy Fluoroscopy () is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a physician to see the internal structure and function ...

, and

nuclear medicine Nuclear medicine or nucleology is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear imaging, in a sense, is " radiology done inside out" because it records radiation emi ...

including positron emission tomography (PET). Interventional radiology is the performance of usually minimally invasive medical procedures with the guidance of imaging technologies such as those mentioned above. The modern practice of radiology involves several different healthcare professions working as a team. The radiologist is a medical doctor who has completed the appropriate post-graduate training and interprets medical images, communicates these findings to other physicians by means of a report or verbally, and uses imaging to perform minimally invasive medical procedures. The nurse is involved in the care of patients before and after imaging or procedures, including administration of medications, monitoring of vital signs and monitoring of sedated patients. The radiographer, also known as a "radiologic technologist" in some countries such as the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

and

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

, is a specially trained healthcare professional that uses sophisticated technology and positioning techniques to produce medical images for the radiologist to interpret. Depending on the individual's training and country of practice, the radiographer may specialize in one of the above-mentioned imaging modalities or have expanded roles in image reporting.

Diagnostic imaging modalities

Projection (plain) radiography

Radiographs Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeut ...

(originally called roentgenographs, named after the discoverer of

X-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

Wilhelm Conrad Röntgen Wilhelm may refer to: People and fictional characters * William Charles John Pitcher, costume designer known professionally as "Wilhelm" * Wilhelm (name), a list of people and fictional characters with the given name or surname Other uses * Mount ...

) are produced by transmitting X-rays through a patient. The X-rays are projected through the body onto a detector; an image is formed based on which rays pass through (and are detected) versus those that are absorbed or scattered in the patient (and thus are not detected). Röntgen discovered X-rays on November 8, 1895, and received the first

Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

for his discovery in 1901. In film-screen radiography, an X-ray tube generates a beam of X-rays, which is aimed at the patient. The X-rays that pass through the patient are filtered through a device called a grid or

X-ray filter An X-ray filter is a material placed in front of an X-ray source in order to reduce the intensity of particular wavelengths from its spectrum and selectively alter the distribution of X-ray wavelengths within a given beam. When X-rays hit matter, p ...

, to reduce scatter, and strike an undeveloped film, which is held tightly to a screen of light-emitting phosphors in a light-tight cassette. The film is then developed chemically and an image appears on the film. Film-screen radiography is being replaced by

phosphor plate radiography Photostimulated luminescence (PSL) is the release of stored energy within a phosphor by stimulation with visible light, to produce a luminescent signal. X-rays may induce such an energy storage. A plate based on this mechanism is called a photostimu ...

but more recently by

digital radiography Digital radiography is a form of radiography that uses x-ray–sensitive plates to directly capture data during the patient examination, immediately transferring it to a computer system without the use of an intermediate cassette. Advantages inclu ...

(DR) and the EOS imaging. In the two latest systems, the X-rays strike sensors that converts the signals generated into digital information, which is transmitted and converted into an image displayed on a computer screen. In

the sensors shape a plate, but in the EOS system, which is a slot-scanning system, a linear sensor vertically scans the patient. Plain radiography was the only imaging modality available during the first 50 years of radiology. Due to its availability, speed, and lower costs compared to other modalities, radiography is often the first-line test of choice in radiologic diagnosis. Also despite the large amount of data in CT scans, MR scans and other digital-based imaging, there are many disease entities in which the classic diagnosis is obtained by plain radiographs. Examples include various types of arthritis and pneumonia, bone tumors (especially benign bone tumors), fractures, congenital skeletal anomalies, and certain kidney stones. Mammography and

DXA Dual-energy X-ray absorptiometry (DXA, or DEXA) is a means of measuring bone mineral density (BMD) using spectral imaging. Two X-ray beams, with different energy levels, are aimed at the patient's bones. When soft tissue absorption is subtracted ...

are two applications of low energy projectional radiography, used for the evaluation for

breast cancer Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or a r ...

and osteoporosis, respectively.

Fluoroscopy

Fluoroscopy and

angiography Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is perfor ...

are special applications of

imaging, in which a fluorescent screen and image intensifier tube is connected to a closed-circuit television system. This allows real-time imaging of structures in motion or augmented with a

radiocontrast Radiocontrast agents are substances used to enhance the visibility of internal structures in X-ray-based imaging techniques such as computed tomography ( contrast CT), projectional radiography, and fluoroscopy. Radiocontrast agents are typically i ...

agent. Radiocontrast agents are usually administered by swallowing or injecting into the body of the patient to delineate anatomy and functioning of the blood vessels, the genitourinary system, or the gastrointestinal tract (GI tract). Two radiocontrast agents are presently in common use. Barium sulfate (BaSO₄) is given orally or rectally for evaluation of the GI tract. Iodine, in multiple proprietary forms, is given by oral, rectal, vaginal, intra-arterial or intravenous routes. These radiocontrast agents strongly absorb or scatter X-rays, and in conjunction with the real-time imaging, allow demonstration of dynamic processes, such as

peristalsis Peristalsis ( , ) is a radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an anterograde direction. Peristalsis is progression of coordinated contraction of involuntary circular muscles, whic ...

in the digestive tract or blood flow in arteries and veins. Iodine contrast may also be concentrated in abnormal areas more or less than in normal tissues and make abnormalities ( tumors, cysts,

inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

) more conspicuous. Additionally, in specific circumstances, air can be used as a contrast agent for the gastrointestinal system and carbon dioxide can be used as a contrast agent in the venous system; in these cases, the contrast agent attenuates the X-ray radiation less than the surrounding tissues.

Computed tomography

CT imaging uses X-rays in conjunction with computing

algorithm In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing ...

s to image the body. In CT, an X-ray tube opposite an X-ray detector (or detectors) in a ring-shaped apparatus rotate around a patient, producing a computer-generated cross-sectional image (tomogram). CT is acquired in the axial plane, with coronal and sagittal images produced by computer reconstruction. Radiocontrast agents are often used with CT for enhanced delineation of anatomy. Although radiographs provide higher spatial resolution, CT can detect more subtle variations in attenuation of X-rays (higher contrast resolution). CT exposes the patient to significantly more ionizing radiation than a radiograph. Spiral multidetector CT uses 16, 64, 254 or more detectors during continuous motion of the patient through the radiation beam to obtain fine detail images in a short exam time. With rapid administration of intravenous contrast during the CT scan, these fine detail images can be reconstructed into three-dimensional (3D) images of carotid, cerebral, coronary or other arteries. The introduction of computed tomography in the early 1970s revolutionized diagnostic radiology by providing Clinicians with images of real three-dimensional anatomic structures. CT scanning has become the test of choice in diagnosing some urgent and emergent conditions, such as cerebral hemorrhage,

pulmonary embolism Pulmonary embolism (PE) is a blockage of an artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream ( embolism). Symptoms of a PE may include shortness of breath, chest pain particularly upon breathin ...

(clots in the arteries of the lungs),

aortic dissection Aortic dissection (AD) occurs when an injury to the innermost layer of the aorta allows blood to flow between the layers of the aortic wall, forcing the layers apart. In most cases, this is associated with a sudden onset of severe chest or ...

(tearing of the aortic wall), appendicitis, diverticulitis, and obstructing kidney stones. Continuing improvements in CT technology, including faster scanning times and improved resolution, have dramatically increased the accuracy and usefulness of CT scanning, which may partially account for increased use in medical diagnosis.

Ultrasound

Medical ultrasonography uses ultrasound (high-frequency sound waves) to visualize soft tissue structures in the body in real time. No ionizing radiation is involved, but the quality of the images obtained using ultrasound is highly dependent on the skill of the person (ultrasonographer) performing the exam and the patient's body size. Examinations of larger, overweight patients may have a decrease in image quality as their

subcutaneous fat The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells, and macro ...

absorbs more of the sound waves. This results in fewer sound waves penetrating to organs and reflecting back to the transducer, resulting in loss of information and a poorer quality image. Ultrasound is also limited by its inability to image through air pockets (lungs, bowel loops) or bone. Its use in medical imaging has developed mostly within the last 30 years. The first ultrasound images were static and two-dimensional (2D), but with modern ultrasonography, 3D reconstructions can be observed in real time, effectively becoming "4D". Because ultrasound imaging techniques do not employ ionizing radiation to generate images (unlike radiography, and CT scans), they are generally considered safer and are therefore more common in obstetrical imaging. The progression of pregnancies can be thoroughly evaluated with less concern about damage from the techniques employed, allowing early detection and diagnosis of many fetal anomalies. Growth can be assessed over time, important in patients with chronic disease or pregnancy-induced disease, and in multiple pregnancies (twins, triplets, etc.). Color-flow Doppler ultrasound measures the severity of

peripheral vascular disease Peripheral artery disease (PAD) is an abnormal narrowing of arteries other than those that supply the heart or brain. When narrowing occurs in the heart, it is called coronary artery disease, and in the brain, it is called cerebrovascular dise ...

and is used by cardiologists for dynamic evaluation of the heart, heart valves and major vessels. Stenosis, for example, of the

carotid arteries In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
stroke. A

clot A thrombus (plural thrombi), colloquially called a blood clot, is the final product of the blood coagulation step in hemostasis. There are two components to a thrombus: aggregated platelets and red blood cells that form a plug, and a mesh of cr ...

, embedded deep in one of the inner veins of the legs, can be found via ultrasound before it dislodges and travels to the lungs, resulting in a potentially fatal

. Ultrasound is useful as a guide to performing biopsies to minimize damage to surrounding tissues and in drainages such as

thoracentesis Thoracentesis , also known as thoracocentesis (from Greek ''thōrax'' 'chest, thorax'—GEN ''thōrakos''—and ''kentēsis'' 'pricking, puncture'), pleural tap, needle thoracostomy, or needle decompression (often used term), is an invasive med ...

. Small, portable ultrasound devices now replace peritoneal lavage in trauma wards by non-invasively assessing for the presence of internal

bleeding Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...

and any internal organ damage. Extensive internal bleeding or injury to the major organs may require surgery and repair.

Magnetic resonance imaging

MRI uses strong magnetic fields to align atomic nuclei (usually

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic ...

protons) within body tissues, then uses a radio signal to disturb the axis of rotation of these nuclei and observes the

radio frequency Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the ...

signal generated as the nuclei return to their baseline states. The radio signals are collected by small antennae, called coils, placed near the area of interest. An advantage of MRI is its ability to produce images in axial, coronal,

sagittal The sagittal plane (; also known as the longitudinal plane) is an anatomical plane that divides the body into right and left sections. It is perpendicular to the transverse and coronal planes. The plane may be in the center of the body and divi ...

and multiple oblique planes with equal ease. MRI scans give the best soft tissue contrast of all the imaging modalities. With advances in scanning speed and spatial resolution, and improvements in computer 3D algorithms and hardware, MRI has become an important tool in musculoskeletal radiology and neuroradiology. One disadvantage is the patient has to hold still for long periods of time in a noisy, cramped space while the imaging is performed. Claustrophobia (fear of closed spaces) severe enough to terminate the MRI exam is reported in up to 5% of patients. Recent improvements in magnet design including stronger magnetic fields (3 teslas), shortening exam times, wider, shorter magnet bores and more open magnet designs, have brought some relief for claustrophobic patients. However, for magnets with equivalent field strengths, there is often a trade-off between image quality and open design. MRI has great benefit in imaging the brain, spine, and musculoskeletal system. The use of MRI is currently contraindicated for patients with pacemakers, cochlear implants, some indwelling medication pumps, certain types of cerebral aneurysm clips, metal fragments in the eyes and some metallic hardware due to the powerful magnetic fields and strong fluctuating radio signals to which the body is exposed. Areas of potential advancement include functional imaging, cardiovascular MRI, and MRI-guided therapy.

Nuclear medicine

Nuclear medicine imaging involves the administration into the patient of radiopharmaceuticals consisting of substances with affinity for certain body tissues labeled with radioactive tracer. The most commonly used tracers are technetium-99m, iodine-123, iodine-131, gallium-67, indium-111, thallium-201 and fludeoxyglucose (¹⁸F) (¹⁸F-FDG). The

heart The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to t ...

, lungs,

thyroid The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...

liver The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it ...

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...

gallbladder In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath the liver, although ...

, and bones are commonly evaluated for particular conditions using these techniques. While anatomical detail is limited in these studies, nuclear medicine is useful in displaying physiological function. The excretory function of the kidneys, iodine-concentrating ability of the thyroid, blood flow to heart muscle, etc. can be measured. The principal imaging devices are the

gamma camera A gamma camera (γ-camera), also called a scintillation camera or Anger camera, is a device used to image gamma radiation emitting radioisotopes, a technique known as scintigraphy. The applications of scintigraphy include early drug development ...

and the PET Scanner, which detect the radiation emitted by the tracer in the body and display it as an image. With computer processing, the information can be displayed as axial, coronal and sagittal images (single-photon emission computed tomography - SPECT or Positron-emission tomography - PET). In the most modern devices, nuclear medicine images can be fused with a CT scan taken quasisimultaneously, so the physiological information can be overlaid or coregistered with the anatomical structures to improve diagnostic accuracy. Positron emission tomography (PET) scanning deals with positrons instead of gamma rays detected by

s. The positrons annihilate to produce two opposite traveling gamma rays to be detected coincidentally, thus improving resolution. In PET scanning, a radioactive, biologically active substance, most often ¹⁸F-FDG, is injected into a patient and the radiation emitted by the patient is detected to produce multiplanar images of the body. Metabolically more active tissues, such as cancer, concentrate the active substance more than normal tissues. PET images can be combined (or "fused") with anatomic (CT) imaging, to more accurately localize PET findings and thereby improve diagnostic accuracy. The fusion technology has gone further to combine PET and MRI similar to PET and CT. PET/MRI fusion, largely practiced in academic and research settings, could potentially play a crucial role in fine detail of brain imaging, breast cancer screening, and small joint imaging of the foot. The technology recently blossomed after passing the technical hurdle of altered positron movement in strong magnetic field thus affecting the resolution of PET images and attenuation correction.

Interventional radiology

Interventional radiology (IR or sometimes VIR for vascular and interventional radiology) is a subspecialty of radiology in which minimally invasive procedures are performed using image guidance. Some of these procedures are done for purely diagnostic purposes (e.g.,

angiogram Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is performe ...

), while others are done for treatment purposes (e.g.,

angioplasty Angioplasty, is also known as balloon angioplasty and percutaneous transluminal angioplasty (PTA), is a minimally invasive endovascular procedure used to widen narrowed or obstructed arteries or veins, typically to treat arterial atheroscle ...

). The basic concept behind interventional radiology is to diagnose or treat

pathologies Pathology is the study of the causes and effects of disease or injury. The word ''pathology'' also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in ...

, with the most minimally invasive technique possible. Minimally invasive procedures are currently performed more than ever before. These procedures are often performed with the patient fully awake, with little or no sedation required. Interventional radiologists and interventional radiographers diagnose and treat several disorders, including

renal artery stenosis Renal artery stenosis (RAS) is the narrowing of one or both of the renal arteries, most often caused by atherosclerosis or fibromuscular dysplasia. This narrowing of the renal artery can impede blood flow to the target kidney, resulting in renov ...

inferior vena cava The inferior vena cava is a large vein that carries the deoxygenated blood from the lower and middle body into the right atrium of the heart. It is formed by the joining of the right and the left common iliac veins, usually at the level of th ...

filter placement, gastrostomy tube placements, biliary

stents In medicine, a stent is a metal or plastic tube inserted into the lumen of an anatomic vessel or duct to keep the passageway open, and stenting is the placement of a stent. A wide variety of stents are used for different purposes, from expanda ...

and

hepatic The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it is ...

interventions. Radiographic images, fluoroscopy, and ultrasound modalities are used for guidance, and the primary instruments used during the procedure are specialized needles and

catheter In medicine, a catheter (/ˈkæθətər/) is a thin tubing (material), tube made from medical grade materials serving a broad range of functions. Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgi ...

s. The images provide maps that allow the clinician to guide these instruments through the body to the areas containing disease. By minimizing the physical trauma to the patient, peripheral interventions can reduce infection rates and recovery times, as well as hospital stays. To be a trained interventionalist in the United States, an individual completes a five-year residency in radiology and a one- or two-year fellowship in IR.

Analysis of images

Plain, or general, radiography

The basic technique is optical density evaluation (i.e. histogram analysis). It is then described that a region has a different optical density, e.g. a cancer metastasis to bone can cause radiolucency. The development of this is the digital radiological subtraction. It consists in overlapping two radiographs of the same examined region and subtracting the optical densitie

The resultant image only contains the time-dependent differences between the two examined radiographs. The advantage of this technique is the precise determination of the dynamics of density changes and the place of their occurrence. However, beforehand the geometrical adjustment and general alignment of optical density should be don

Another possibility of radiographic image analysis is to study second order features, e.g. digital texture analysi

or fractal dimensio

On this basis, it is possible to assess the places where bio-materials are implanted into the bone for the purpose of guided bone regeneration. They take an intact bone image sample (region of interest, ROI, reference site) and a sample of the implantation site (second ROI, test site) can be assessed numerically/objectively to what extent the implantation site imitates a healthy bone and how advanced is the process of bone regeneratio

It is also possible to check whether the bone healing process is influenced by some systemic factor

Teleradiology

Teleradiology is the transmission of radiographic images from one location to another for interpretation by an appropriately trained professional, usually a radiologist or reporting radiographer. It is most often used to allow rapid interpretation of emergency room, ICU and other emergent examinations after hours of usual operation, at night and on weekends. In these cases, the images can be sent across time zones (e.g. to Spain, Australia, India) with the receiving Clinician working his normal daylight hours. However, at present, large private teleradiology companies in the U.S. currently provide most after-hours coverage employing night-working radiologists in the U.S. Teleradiology can also be used to obtain consultation with an expert or subspecialist about a complicated or puzzling case. In the U.S., many hospitals outsource their radiology departments to radiologists in India due to the lowered cost and availability of high speed internet access. Teleradiology requires a sending station, a high-speed internet connection, and a high-quality receiving station. At the transmission station, plain radiography, radiographs are passed through a digitizing machine before transmission, while CT, MRI, ultrasound and nuclear medicine scans can be sent directly, as they are already digital data. The computer at the receiving end will need to have a high-quality display screen that has been tested and cleared for clinical purposes. Reports are then transmitted to the requesting clinician. The major advantage of teleradiology is the ability to use different time zones to provide real-time emergency radiology services around-the-clock. The disadvantages include higher costs, limited contact between the referrer and the reporting Clinician, and the inability to cover for procedures requiring an onsite reporting Clinician. Laws and regulations concerning the use of teleradiology vary among the states, with some requiring a license to practice medicine in the state sending the radiologic exam. In the U.S., some states require the teleradiology report to be preliminary with the official report issued by a hospital staff radiologist. Lastly, a benefit of teleradiology is that it might be automated with modern

machine learning Machine learning (ML) is a field of inquiry devoted to understanding and building methods that 'learn', that is, methods that leverage data to improve performance on some set of tasks. It is seen as a part of artificial intelligence. Machine ...

techniques. X-ray of hand, where bone age is automatically found by BoneXpert software

Professional training

United States

Radiology is a field in medicine that has expanded rapidly after 2000 due to advances in computer technology, which is closely linked to modern imaging techniques. Applying for residency positions in radiology is relatively competitive. Applicants are often near the top of their medical school classes, with high

USMLE The United States Medical Licensing Examination (USMLE) is a three-step examination program for medical licensure in the United States sponsored by the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). ...

(board) examination scores. Diagnostic radiologists must complete prerequisite undergraduate education, four years of medical school to earn a medical degree ( D.O. or

M.D. Doctor of Medicine (abbreviated M.D., from the Latin ''Medicinae Doctor'') is a medical degree, the meaning of which varies between different jurisdictions. In the United States, and some other countries, the M.D. denotes a professional degree. ...

), one year of internship, and four years of residency training. After residency, radiologists may pursue one or two years of additional specialty fellowship training. The American Board of Radiology (ABR) administers professional certification in Diagnostic Radiology, Radiation Oncology and Medical Physics as well as subspecialty certification in neuroradiology, nuclear radiology, pediatric radiology and vascular and interventional radiology. "Board Certification" in diagnostic radiology requires successful completion of two examinations. The Core Exam is given after 36 months of residency. Although previously taken in Chicago or Tucson, Arizona, beginning in February 2021, the computer test transitioned permanently to a remote format. It encompasses 18 categories. A passing score is 350 or above. A fail on one to five categories was previously a Conditioned exam, however beginning in June 2021, the conditioned category will no longer exist and the test will be graded as a whole. The Certification Exam, can be taken 15 months after completion of the Radiology residency. This computer-based examination consists of five modules and graded pass-fail. It is given twice a year in Chicago and Tucson. Recertification examinations are taken every 10 years, with additional required continuing medical education as outlined in the Maintenance of Certification document. Certification may also be obtained from the

American Osteopathic Board of Radiology The American Osteopathic Board of Radiology (AOBR) is an organization that provides board certification to qualified Doctors of Osteopathic Medicine (D.O.) who specialize in the use of imaging in the diagnosis and treatment of disease (radiologi ...

(AOBR) and the American Board of Physician Specialties. Following completion of residency training, radiologists may either begin practicing as a general diagnostic radiologist or enter into subspecialty training programs known as fellowships. Examples of subspeciality training in radiology include abdominal imaging, thoracic imaging, cross-sectional/ultrasound,

MRI Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

musculoskeletal The human musculoskeletal system (also known as the human locomotor system, and previously the activity system) is an organ system that gives humans the ability to move using their muscular and skeletal systems. The musculoskeletal system prov ...

imaging, interventional radiology,

neuroradiology Neuroradiology is a subspecialty of radiology focusing on the diagnosis and characterization of abnormalities of the central and peripheral nervous system, spine, and head and neck using neuroimaging techniques. Medical issues utilizing neuroradio ...

, interventional neuroradiology, paediatric radiology, nuclear medicine, emergency radiology, breast imaging and women's imaging. Fellowship training programs in radiology are usually one or two years in length. Some medical schools in the US have started to incorporate a basic radiology introduction into their core MD training. New York Medical College, the Wayne State University School of Medicine,

Weill Cornell Medicine The Joan & Sanford I. Weill Medical College of Cornell University is Cornell University's biomedical research unit and medical school located in Upper East Side, Manhattan, New York City, New York. Weill Cornell Medicine is affiliated with N ...

, the Uniformed Services University, and the University of South Carolina School of Medicine offer an introduction to radiology during their respective MD programs. Campbell University School of Osteopathic Medicine also integrates imaging material into their curriculum early in the first year. Radiographic exams are usually performed by radiographers. Qualifications for radiographers vary by country, but many radiographers now are required to hold a degree. Veterinary radiologists are veterinarians who specialize in the use of X-rays, ultrasound, MRI and nuclear medicine for diagnostic imaging or treatment of disease in animals. They are certified in either diagnostic radiology or radiation oncology by the American College of Veterinary Radiology.

United Kingdom

Radiology is an extremely competitive speciality in the UK, attracting applicants from a broad range of backgrounds. Applicants are welcomed directly from the foundation programme, as well as those who have completed higher training. Recruitment and selection into training post in clinical radiology posts in England, Scotland and Wales is done by an annual nationally coordinated process lasting from November to March. In this process, all applicants are required to pass a Specialty Recruitment Assessment (SRA) test. Those with a test score above a certain threshold are offered a single interview at the London and the South East Recruitment Office. At a later stage, applicants declare what programs they prefer, but may in some cases be placed in a neighbouring region. The training programme lasts for a total of five years. During this time, doctors rotate into different subspecialities, such as paediatrics, musculoskeletal or neuroradiology, and breast imaging. During the first year of training, radiology trainees are expected to pass the first part of the Fellowship of the Royal College of Radiologists (FRCR) exam. This comprises a medical physics and anatomy examination. Following completion of their part 1 exam, they are then required to pass six written exams (part 2A), which cover all the subspecialities. Successful completion of these allows them to complete the FRCR by completing part 2B, which includes rapid reporting, and a long case discussion. After achieving a certificate of completion of training (CCT), many fellowship posts exist in specialities such as neurointervention and vascular intervention, which would allow the doctor to work as an Interventional radiologist. In some cases, the CCT date can be deferred by a year to include these fellowship programmes. UK radiology registrars are represented by the Society of Radiologists in Training (SRT), which was founded in 1993 under the auspices of the Royal College of Radiologists. The society is a nonprofit organisation, run by radiology registrars specifically to promote radiology training and education in the UK. Annual meetings are held by which trainees across the country are encouraged to attend. Currently, a shortage of radiologists in the UK has created opportunities in all specialities, and with the increased reliance on imaging, demand is expected to increase in the future.

Radiographer Radiographers, also known as radiologic technologists, diagnostic radiographers and medical radiation technologists are healthcare professionals who specialize in the imaging of human anatomy for the diagnosis and treatment of pathology. Radi ...

s, and less frequently

Nurse Nursing is a profession within the health care sector focused on the care of individuals, families, and communities so they may attain, maintain, or recover optimal health and quality of life. Nurses may be differentiated from other health c ...

s, are often trained to undertake many of these opportunities in order to help meet demand. Radiographers often may control a "list" of a particular set of procedures after being approved locally and signed off by a consultant radiologist. Similarly, radiographers may simply operate a list for a radiologist or other physician on their behalf. Most often if a radiographer operates a list autonomously then they are acting as the operator and practitioner under the Ionising Radiation (Medical Exposures) Regulations 2000. Radiographers are represented by a variety of bodies; most often this is the

Society and College of Radiographers The Society of Radiographers (SoR) is a professional body and trade union that represents more than 90 percent of the diagnostic and therapeutic radiographers in the United Kingdom. The College of Radiographers (CoR) is a charitable subsidiary o ...

. Collaboration with nurses is also common, where a list may be jointly organised between the nurse and radiographer.

Germany

After obtaining medical licensure, German radiologists complete a five-year residency, culminating with a board examination (known as ''Facharztprüfung'').

Italy

Italian radiologists complete a four-year residency program after completing the six-year MD program.

The Netherlands

Dutch radiologists complete a five-year residency program after completing the six-year MD program.

India

In India a medical graduate must obtain a bachelors degree which requires 4.5 year of training along with 1 year internship followed by NEET PG examination which is one of the hardest examination in India .Then on the merit basis one must get into Radio diagnosis .previous rank data shows only top rankers take radiology means if your score is less you might get other branches but not radiology.The radiology training course is a post graduate 3-year program (MD/DNB Radiology) or a 2-year diploma (DMRD).

Singapore

Radiologists in Singapore complete a five-year undergraduate medicine degree followed by a one-year

internship An internship is a period of work experience offered by an organization for a limited period of time. Once confined to medical graduates, internship is used practice for a wide range of placements in businesses, non-profit organizations and gover ...

and then a five-year residency program. Some radiologists may elect to complete a one or two-year fellowship for further sub-specialization in fields such as interventional radiology. Slovenia After finishing a 6-year study of medicine and passing the emergency medicine internship, MDs can apply for radiology residency. Radiology is a 5-year post-graduate programme that involves all fields of radiology with final board exam.

Specialty training for interventional radiology

United States

Training for interventional radiology occurs in the residency portion of

medical education Medical education is education related to the practice of being a medical practitioner, including the initial training to become a physician (i.e., medical school and internship) and additional training thereafter (e.g., residency, fellowship, ...

, and has gone through developments. In 2000, the

Society of Interventional Radiology The Society of Interventional Radiology (SIR) is an American national organization of physicians, scientists and allied health professionals dedicated to improving public health through the use of minimally invasive, image-guided therapeutic inte ...

(SIR) created a program named "Clinical Pathway in IR", which modified the "Holman Pathway" that was already accepted by the American Board of Radiology to including training in IR; this was accepted by ABR but was not widely adopted. In 2005 SIR proposed and ABR accepted another pathway called "DIRECT (Diagnostic and Interventional Radiology Enhanced Clinical Training) Pathway" to help trainees coming from other specialities learn IR; this too was not widely adopted. In 2006 SIR proposed a pathway resulting in certification in IR as a speciality; this was eventually accepted by the ABR in 2007 and was presented to the

American Board of Medical Specialities Established in 1933, the American Board of Medical Specialties (ABMS) is a non-profit organization which represent 24 broad areas of specialty medicine. ABMS is the largest physician-led specialty certification organization in the United States ...

(ABMS) in 2009, which rejected it because it did not include enough

diagnostic radiology Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues ( physiology). Medical imaging seeks to r ...

(DR) training. The proposal was reworked, at the same time that overall DR training was being revamped, and a new proposal that would lead to a dual DR/IR specialization was presented to the ABMS and was accepted in 2012 and eventually was implemented in 2014. By 2016 the field had determined that the old IR fellowships would be terminated by 2020. A handful of programs have offered interventional radiology fellowships that focus on training in the treatment of children.

Europe

In Europe the field followed its own pathway; for example in Germany the parallel interventional society began to break free of the DR society in 2008. In the UK, interventional radiology was approved as a sub-specialty of clinical radiology in 2010. While many countries have an interventional radiology society, there is also the European-wide Cardiovascular and Interventional Radiological Society of Europe, whose aim is to support teaching, science, research and clinical practice in the field by hosting meetings, educational workshops and promoting patient safety initiatives. Furthermore, the Society provides an examination, the European Board of Interventional Radiology (EBIR), which is a highly valuable qualification in interventional radiology based on the European Curriculum and Syllabus for IR.

References

External links

* {{Authority control Medical imaging Medical physics

Diagnostic imaging modalities

Projection (plain) radiography

Fluoroscopy

Computed tomography

Ultrasound

Magnetic resonance imaging

Nuclear medicine

Interventional radiology

Analysis of images

Plain, or general, radiography

Teleradiology

Professional training

United States

United Kingdom

Germany

Italy

The Netherlands

India

Singapore

Specialty training for interventional radiology

United States

Europe

See also

References

External links