9 Radiology Subspecialties You Should Know - BrettMollard.com Blog

Are you interested in radiology?

Radiology is a fascinating field of medicine that offers many opportunities for specialization.

By reading this article, you will learn about the different radiology subspecialties and what each one entails.

What is Radiology?

Radiology is the study and practice of imaging the human body.

Radiology is frequently at the heart of medicine and plays a vital part in healthcare around the world.

Radiologists are physicians specialized in diagnostic radiology, utilizing ionizing (x-rays) and non-ionizing (ultrasound, magnetic resonance imaging/MRI) radiation and radioactive substances to guide patient management through diagnostic imaging and both diagnostic and therapeutic image-guided procedures and interventions.

Becoming a radiologist is no easy task. And similar to many other specialties such as internal medicine and surgery, radiologists frequently subspecialize to gain further information and master various subspecialties following completion of a radiology residency.

Diagnostic radiology residencies are either five years or four years (depending on if their intern year is included or separate). Afterward, most diagnostic radiologists subspecialize through fellowship training.

There is wide variability in the types of fellowships available, their structure, and whether or not they have a special certification following completion.

Radiology Subspecialties

Let’s dive into some of the most common subspecialties you’re likely to come across.

Abdominal Imaging – The best of the radiology subspecialties!

Abdominal Imaging is one of the most important and familiar subspecialties in radiology. It encompasses a wide range of imaging techniques used to diagnose problems in the abdomen and pelvis, including the liver, gallbladder, pancreas, spleen, intestines, kidneys and ureters, pelvic organs, and more.

Some of the most common abdominal imaging procedures include ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI).

Abdominal Imaging fellowships are typically 1 year long and may also include extra training in fluoroscopy and/or image-guided procedures such as biopsies, ablations, and fluid or abscess drainage, which means we also get to see patients!

Abdominal imagers interpret high-end MRI and multi-phase CT exams and have several specific protocols tailored toward diagnosing and staging various cancers, including rectal, prostate, liver, and cervical cancer to name a few. Abdominal imagers may also aid in cancer screening, such as CT Colonography (aka Virtual Colonoscopy).

Cardiothoracic (Chest) Imaging

Cardiothoracic Imaging is a subspecialty of radiology that focuses on the heart (cardio-) and other entities in the chest such as the lungs and mediastinal structures (-thoracic). They have a vast knowledge of major pathologies (and normal variants) that occur in the thorax and play an important role in lung cancer management, from screening to staging and restaging following/during treatment.

Cardiothoracic radiologists also frequently interpret cardiac imaging, primarily consisting of cardiac computed tomography angiography (CTA) and cardiac MRI. These examinations are used to diagnose and risk-stratify diseases such as coronary artery disease, myocardial viability in the setting of myocardial infarction (heart attacks), diagnose cardiac masses, and aid in the work-up of various types of cardiomyopathy and inflammatory heart conditions such as cardiac sarcoidosis.

Cardiothoracic fellowships are typically 1 year long of extra dedicated training.

Emergency Radiology

Emergency Radiology (ER) is a subspecialty of radiology with extra training that focuses on the diagnosis of acute medical conditions, particularly, as you would expect, in the emergency setting. The training generally covers various types of traumas (high-energy motor vehicle collisions to penetrating gunshot and stabbings injuries), stroke, spinal cord injury, common infections, vascular injuries, and more.

Emergency radiology covers the whole gamut, from x-rays and ultrasound to CT and MRI, and even may include some nuclear radiology.

ER fellowships are generally associated with level 1 trauma centers where they see high volumes of high-acuity traumatic injuries.

Interventional Radiology

Interventional Radiology (IR) is a subspecialty of radiology that focuses on minimally invasive image-guided procedures and interventions. Interventional radiologists play a critical role in the diagnosis and treatment of a wide spectrum of disease pathologies from vascular stenosis/occlusion to numerous different cancers.

Interventional radiologists perform a wide variety of procedures including angiography, angioplasty, stent placement, biopsy, embolization, central line and chest port placement, percutaneous abscess drainage, and many more.

Interventional radiology now exists as a stand-alone, 6-year residency program essentially inclusive of a fellowship year. IR training focuses on patient care, technical aspects of higher-end interventional procedures, and the management of post-procedural care including management of potential complications.

Mammography/Women’s Imaging

Mammography fellowships typically consist of 1 year of extra dedicated training in mammography and tomosynthesis (3D mammography), including image-guided mammography-specific procedures, and may contain dedicated training concerning imaging of the female reproductive system.

The subspecialty consists of screening and diagnostic mammography, ultrasound, and MRI. Some fellowships also include some abdominal imaging with a focus on the female reproductive system (imaging of the uterus and ovaries).

Mammographers follow specific algorithms, use a dedicated lexicon, and must abide by specific quality standards. They play a crucial role in the screening and diagnosis of breast cancers and have direct interaction with patients and physicians such as breast surgeons and medical oncologists.

Musculoskeletal Imaging

Musculoskeletal (MSK) Imaging focuses on the imaging of the bones, joints, and muscles. Musculoskeletal imaging procedures include x-ray, CT, and MRI.

MSK radiologists play an important role in the diagnosis of conditions such as musculoskeletal trauma, joint degeneration (osteoarthritis), ligamentous injury, inflammatory and non-inflammatory arthritis, and septic arthritis.

MSK radiologists frequently perform joint injections (arthrograms) for both diagnostic (MRI or CT arthrograms) and therapeutic (treatment of arthritis symptoms) purposes.


Neuroradiology is a subspecialty that focuses on the central nervous system – the brain and spine (though MSK may also have advanced training when it comes to spines) and neck.

Neuroradiology fellowships are either 1 or 2 years long, depending on the program.

Neuroradiology exams include x-rays, CT, MRI, and angiography (interventional neuroradiology, which requires an additional fellowship).

Neuroradiologists play a crucial role in the diagnosis, work-up, and treatment of stroke, brain tumors, and spinal injury or degeneration. They may interpret stroke perfusion exams as well, which are useful in assessing whether patients are likely to benefit from intervention.

Nuclear Radiology

Nuclear radiology, also referred to as nuclear medicine, is a unique field in that it exists as both a 2-year residency outside of radiology and a 1-year radiology fellowship. Rather than imaging x-rays, nuclear medicine images gamma-rays. These are essentially the same as x-rays but are produced by radioactive elements.

Nuclear medicine is often referred to as “unclear medicine” as the imaging cameras provide images of low quality that most physicians are less comfortable looking at. In reality, it’s very straightforward and simply imaging physiological processes within the human body.

A nuclear medicine physician interprets cardiac stress tests (myocardial perfusion imaging), positron emission tomography (PET) scans, and a wide variety of less commonly known tests such as bone scans, gastric emptying exams, HIDA scans, and ventilation/perfusion scans.

Nuclear radiologists can also treat patients with various tumors and certain thyroid conditions but must understand radiation safety standards to ensure patients receive an appropriate radiation dose and do not expose their family and friends to radiation as they become walking gamma-ray machines until the radioactivity has left their bodies.

Pediatric Radiology

Pediatric Radiology is a subspecialty of radiology that focuses on the imaging of infants, children, and adolescents. Pediatric radiology fellowships are generally 1 year of additional training and are found at large academic centers with dedicated pediatric hospitals.

Pediatric radiology consists largely of x-rays (for fractures, scoliosis, and bone age assessment), fluoroscopy, and imaging exams utilizing non-ionizing radiation such as ultrasound and MRI. CT is used sparingly when equivalent non-ionizing imaging options exist given the increased radiation sensitivity of pediatric patients.

A pediatric radiologist is an expert when it comes to non-accidental trauma (imaging findings of child abuse), congenital abnormalities, growth disorders, and pediatric-specific diseases and pathologies.


Not all radiologists are the same. In the modern era of medicine, you can expect that each radiologist will specialize or have specialized in a specific area of radiology.

While all radiologists should have basic radiology knowledge covering basic information about general radiology, specific clinical questions are often better answered by a radiologist with advanced training within a specific subspecialty.

The days when a radiologist is a “Jack of all trades and master of none” is falling by the wayside.