CT RENAL ANGIO

A CT Renal Angio is a type of computed tomography (CT) scan that focuses specifically on the renal vasculature. The technology works by taking numerous cross-sectional X-ray images, or "slices," of the kidney area from different angles. A computer then processes these slices to construct comprehensive 3D images.

To make the blood vessels stand out from the surrounding tissues, a special iodine-based contrast material is injected into a vein, usually in your arm. This dye travels through your bloodstream and brightly illuminates the renal arteries and veins on the scan. This process provides your doctor and our radiologists with a detailed "road map" of your renal blood vessels, allowing for a precise evaluation of their structure and function. It is one of the most effective non-invasive methods for visualizing these arteries.

Types of CT Renal Angio

The standard CT Renal Angio provides excellent anatomical detail. However, depending on the clinical question your doctor is trying to answer, we may perform variations of the test:

• Multiphasic Scanning: This advanced technique involves acquiring images at different time points after the contrast injection. For example, an "arterial phase" captures the moment the dye is most concentrated in the arteries, while a "venous phase" or "delayed phase" shows how the dye moves through the veins and is excreted by the kidneys. This helps assess blood flow dynamics and kidney function.
• CT Renal Angio with vs. Without Contrast: While a non-contrast scan can be performed to look for kidney stones or calcifications, a scan with contrast is essential for visualizing the blood vessels clearly. For a renal angiogram, the contrast material is a mandatory component.

After your scan is complete, a specialized radiologist at Cadabams Diagnostics meticulously analyzes the images. They look for specific features and abnormalities within your renal blood vessels. The key parameters considered include:

• Vessel Caliber and Stenosis: The primary goal is often to measure the diameter of the renal arteries and identify any areas of narrowing or blockage (stenosis). The severity of stenosis is usually reported as a percentage.
• Aneurysms or Dissections: The radiologist will look for any abnormal bulges (aneurysms) or tears (dissections) in the walls of the renal arteries or veins.
• Anatomical Variants: About 20-30% of people have more than one artery supplying each kidney. Identifying these anatomical variations is crucial for planning surgeries or kidney donation.
• Thrombosis: The scan can detect the presence of blood clots (thrombosis) within the renal arteries or, less commonly, the renal veins.
• Fibromuscular Dysplasia (FMD): This is a non-inflammatory, non-atherosclerotic vascular disease that causes stenosis. On a CT Renal Angio, it often has a characteristic "string of beads" appearance.
• Vascular Supply to Tumors: If a kidney mass is present, the scan helps determine its blood supply, which is vital information for surgical planning.

Your doctor’s decision to order this test is based on your specific symptoms and medical history. Expanding on the initial reasons, a CT Renal Angio is pivotal in investigating:

• Resistant Hypertension: This is when your blood pressure remains high despite being on three or more different types of antihypertensive medications. It is a classic sign of possible renal artery stenosis.
• Suspected Renal Artery Stenosis: This narrowing of the kidney arteries is the single most common reason for the test. Investigating with a CTA for renal artery stenosis is the gold standard.
• Evaluation of a Kidney Mass: To understand how a tumor or cyst is affecting or being fed by the kidney's blood supply.
• Abdominal Trauma: After an accident or injury, the scan can quickly identify any damage or bleeding from the renal vessels.
• Pre-Surgical Planning: Essential for kidney transplant surgeons to have a detailed map of the donor's and recipient's vascular anatomy to ensure a successful procedure.
• Follow-up After Intervention: To check the success of a procedure like stenting or angioplasty of the renal artery.

When and Who Needs to Take a CT Renal Angio?

Your doctor may recommend a CT Renal Angio for several reasons. The most common indication is for patients who have hypertension (high blood pressure) that is difficult to control with multiple medications. This condition, known as resistant hypertension, is sometimes caused by a narrowing of the renal arteries.

Other common reasons and patient groups include:

• Individuals experiencing a sudden, unexplained decrease in kidney function.

• Patients with suspected vascular abnormalities, such as aneurysms or fibromuscular dysplasia (FMD).

• Potential living kidney donors, to map their renal artery anatomy before surgery.

• Recipients of a kidney transplant, to ensure the new kidney's blood supply is functioning correctly.

• Patients who have suffered trauma to the abdomen or back. Opting for a CT Renal Angio at Cadabams Diagnostics offers significant advantages for your health and treatment plan:

• High Diagnostic Accuracy: It provides extremely clear and precise images, making it one of the best non-invasive tools for diagnosing conditions like renal artery stenosis.

• Less Invasive: Compared to traditional catheter angiography, which requires inserting a catheter into an artery in the groin, a CT angio only needs a simple IV line in the arm.

• Fast and Efficient: The scanning process itself is very quick, often taking less than a minute of actual imaging time.

• Comprehensive Evaluation: The scan provides detailed 3D images that not only diagnose a problem but also help your doctor plan the most effective treatment, whether it's medication, angioplasty, stenting, or surgery.

Benefits of Taking the Test

Opting for a CT Renal Angio at Cadabams Diagnostics offers significant advantages for your health and treatment plan:

• High Diagnostic Accuracy: It provides extremely clear and precise images, making it one of the best non-invasive tools for diagnosing conditions like renal artery stenosis.
• Less Invasive: Compared to traditional catheter angiography, which requires inserting a catheter into an artery in the groin, a CT angio only needs a simple IV line in the arm.
• Fast and Efficient: The scanning process itself is very quick, often taking less than a minute of actual imaging time.
• Comprehensive Evaluation: The scan provides detailed 3D images that not only diagnose a problem but also help your doctor plan the most effective treatment, whether it's medication, angioplasty, stenting, or surgery.

Illnesses Diagnosed with CT Renal Angiography

This powerful imaging test is instrumental in diagnosing a range of vascular conditions affecting the kidneys. Key diagnoses include:

• Renal Artery Stenosis (caused by atherosclerosis or hardening of the arteries)
• Fibromuscular Dysplasia (FMD)
• Renal Artery Aneurysm or Pseudoaneurysm
• Renal Vein Thrombosis (blood clot in the kidney vein)
• Vascular Trauma including arterial dissection or rupture
• Arteriovenous Malformations (AVMs) or Fistulas (abnormal connections between arteries and veins)

Proper preparation for a CT renal angiogram is simple but crucial for ensuring a safe and successful scan. Please follow these instructions carefully:

• Fasting: You will likely be asked not to eat any solid food for about 4 to 6 hours before your scheduled appointment.
• Hydration: Drinking clear liquids like water, clear broth, or plain tea is encouraged. Staying well-hydrated before and after the scan helps your kidneys process and flush out the contrast dye.
• Medication Review: Inform your doctor and our staff about all the medications you are currently taking, including over-the-counter drugs and supplements.
• Metformin: If you are taking Metformin (Glucophage) for diabetes, you will need to stop taking it before the scan and for 48 hours afterward. Your doctor will provide specific instructions.
• Clothing: On the day of the test, wear comfortable, loose-fitting clothes. You may be asked to change into a hospital gown. Avoid wearing clothing with metal zippers or buttons, and remove any jewelry, as metal can interfere with the image quality.

Pre-requisites

Before we can perform the scan, there are two key requirements:

1. Doctor's Referral: A CT Renal Angio must be prescribed by your physician.
2. Kidney Function Test: A recent blood test result for serum creatinine is mandatory. This test measures your kidney function and is essential for us to safely administer the contrast material.

Best Time to Take the CT Renal Angio

There is no specific "best" time of day to have the scan from a medical standpoint. However, the test must be scheduled in advance with our diagnostics center. This ensures the availability of the CT suite and our trained technical staff and gives you adequate time for the necessary preparation, such as fasting.

Eligibility

Most adults are eligible for a CT Renal Angio. The primary factors determining eligibility are:

• Kidney Function: Your eGFR (estimated Glomerular Filtration Rate), calculated from your creatinine level, must be within a safe range for contrast administration.
• Allergies: You must not have a known severe allergy to iodine-based contrast materials. If you have a mild allergy, your doctor may recommend pre-medication with antihistamines or steroids.

Please be sure to discuss your full medical history with your doctor and our staff.

Procedure for Taking a CT Renal Angio

Understanding the ct renal angiography procedure can help you feel more comfortable and prepared on the day of your test. Here is a step-by-step walkthrough of what you can expect at Cadabams Diagnostics:

1. Check-in & Prep: When you arrive, our front desk staff will confirm your details and appointment. A technologist will greet you, explain the procedure, and answer any last-minute questions. You may be asked to change into a hospital gown.
2. IV Line Placement: The technologist will place a small, thin plastic tube called an IV cannula into a vein in your arm or hand. This is the entry point for the contrast dye.
3. Positioning: You will be asked to lie down on your back on the padded CT scanner table. The technologist will ensure you are comfortable. The table will then gently slide into the center of the large, donut-shaped part of the CT machine, known as the gantry.
4. Contrast Injection: Once you are in position, the scan will begin. At a specific moment, the technologist will start the injection of the contrast dye through your IV line. It is very common to feel a warm sensation spreading throughout your body as the dye circulates. Some people also notice a temporary metallic taste in their mouth. These feelings are normal and pass quickly.
5. Scanning and Breath-Holding: The CT machine will rotate around you, capturing the images. To get the clearest pictures possible, the technologist will ask you to hold your breath for short periods (usually 10-15 seconds) at a time. It is very important to remain still during the scan.
6. Completion: The entire scanning process is very fast, often completed in under 15-30 minutes from start to finish. Once all the images are acquired, the table will slide out of the gantry, and the technologist will remove your IV line.

Caution Before Taking the Test

For your safety, it is critically important that you inform the scheduling staff and the CT technologist if you:

• Are or might be pregnant.
• Are currently breastfeeding.
• Have any known allergies, especially to iodine, shellfish, or previous X-ray contrast dyes.
• Have a history of kidney disease, kidney failure, or diabetes.
• Are taking Metformin (Glucophage) or any other medication for diabetes.
• Have a history of asthma or other severe allergies.