Methodsangiography

Methodsangiography is the field devoted to imaging techniques used to visualize blood vessels. It encompasses both invasive catheter-based procedures and noninvasive approaches, with the goal of mapping vascular anatomy, assessing blood flow, and identifying pathology such as aneurysms, stenoses, malformations, and occlusions.

Invasive angiography typically involves catheter insertion with contrast injection and fluoroscopic X-ray imaging. Digital subtraction angiography (DSA) is the standard invasive technique, providing high-contrast visualization of vessels by subtracting background structures. Noninvasive methods include CT angiography (CTA), which uses contrast-enhanced CT to produce three-dimensional vessel images, and MR angiography (MRA), which can be performed with or without gadolinium-based contrast. Time-resolved or four-dimensional MRA can capture dynamic flow information. Ultrasound-based vascular imaging, including Doppler ultrasound and contrast-enhanced ultrasound, offers real-time assessment of flow without ionizing radiation.

Applications of methodsangiography span neurology, cardiology, and vascular surgery. They are used to diagnose intracranial aneurysms and stenosis, coronary and peripheral arterial disease, and to plan or guide interventions such as stenting, embolization, or bypass procedures. The choice of technique depends on clinical question, vessel size, required resolution, patient factors, and safety considerations.

Safety and limitations vary by method. Invasive angiography carries risks of bleeding, infection, arterial injury, and contrast-related complications, along with radiation exposure. Noninvasive methods reduce some risks but may have lower spatial resolution or be affected by motion and artifacts. Contrast safety, availability, and patient-specific factors guide method selection and sequencing.

Historically, angiographic techniques evolved from early catheter-based imaging to modern DSA, CTA, and MRA, expanding the ability to visualize vasculature with greater detail and fewer risks.