What is Digital subtraction angiography?

Digital subtraction angiography (DSA) is a fluoroscopic technique used for visualizing the blood vessels with the help of contrast dye. This procedure eliminates the bone and cartilage from the image so that it provides an accurate view of blood vessels. DSA helps to detect a problem with the blood flow. With the combination of contrast dye and real-time subtraction, a fluoroscopic digital image is formed. Digital Subtraction Angiography is used for diagnostic and therapeutic purposes. 

What are the indications of Digital subtraction angiography?

Digital Subtraction Angiography is indicated in few of the following medical conditions:

• Arterial balloon angioplasty
• Endovascular embolization
• Thrombectomy
• Arterial stenting
• Endovascular aneurysm repair
• Pseudoaneurysm
• Thrombosis
• Arterial laceration or dissection
• Stenting
• Tumor vascularity
• Arterio-venous fistula
• Arterio-venous malformation
• Nontraumatic subarachnoid hemorrhage
• Embolism
• Thrombolysis

What are the contraindications of DSA?

Below conditions are contraindications of Digital Subtraction Angiography:

• Renal insufficiency
• Deranged coagulogram
• Sensitive to contrast media

What are the pre-procedure steps to be taken before DSA?

• Pre-procedure evaluation is recommended before performing DSA procedure
• Check the patient whether he/she has an atherosclerotic disease
• Examine the renal function status
• The patient is asked about medication history
• Check the patient is allergic to any contrast media
• Review of any previous vascular imaging studies
• Previous vascular surgical procedures 

What are the steps involved during DSA procedure?

• Initially local or general anesthesia is given to the patient to reduce anxiety.
• Vital signs like heart rate, breathing, blood pressure are observed throughout the procedure.
• Fluoroscopy is used to guide the needle in the proper direction when a catheter is injected into a blood vessel through a small incision.
• Then, a contrast dye is injected into blood through the catheter if the needle is located in the correct position.
• During contrast dye injection, images are obtained.
• In case of children and older patients, special care should be taken while performing this procedure.

What are the complications related to DSA?

Local complications:

• Injury at the puncture site
• Bleeding
• Tissue damage
• Arteriovenous fistula
• Pseudoaneurysm
• Thrombus formation

Systemic complications:

• Vessel dissection
• Nephrotoxicity due to contrast media
• Air embolism
• Thromboembolism