A kidney arterial ultrasound evaluates blood flow through the renal arteries. Narrowing of these arteries is a common and often missed cause of treatment-resistant high blood pressure and declining kidney function.[1]
The Study
A renal artery ultrasound is a painless scan of the arteries that supply blood to your kidneys. It checks for narrowing that can cause hard-to-control high blood pressure and declining kidney function. The scan uses sound waves with no radiation or needles, takes 30 to 45 minutes, and results are reviewed by a board-certified cardiologist and delivered within 24 to 48 hours.
Renal artery narrowing usually presents as a blood pressure problem rather than a kidney one.
It is also indicated with declining kidney function, blood pressure that suddenly worsened after years of good control, or diabetes with kidney involvement.
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What to Expect
Many people have never had this scan before. Here is exactly what happens — no surprises, no anxiety.
No radiation. No needles. No discomfort. An ultrasound uses sound waves — the same technology used in obstetric imaging. It is entirely safe and non-invasive.
We ask that you avoid eating for 4—6 hours before this scan for the clearest possible images of the kidney arteries.
Gel is applied to your upper abdomen. The sonographer uses a probe to locate and image both renal arteries.
Flow velocities are measured at the origin of each renal artery and along its length to detect any significant narrowing.
We also evaluate kidney size and appearance — chronic narrowing often causes one kidney to shrink over time.
Findings include flow velocity ratios, degree of stenosis if present, kidney size comparison, and clinical interpretation.
What We're Looking For
These conditions often develop without symptoms for years. Early detection changes the outcome dramatically.
Why BlackPoint
Quality cardiovascular imaging shouldn't require a hospital visit, a referral, or a weeks-long wait. Our sonographer performs cardiovascular imaging daily alongside physicians — clinical-grade diagnostics delivered with genuine convenience.
“Manny was professional and informative. The appointment felt clean, quiet and calming. I was able to get scheduled quickly and received my results the very next day.”
— Jennifer S.“He was very professional, kind, and took the time to explain everything he was doing during the procedure, which really helped put me at ease. I received my results within 48 hours, which was impressive. Excellent experience overall.”
— Meagan B.“Manny was respectful and knowledgeable. I was brought in on time and was kept informed of what he was doing along with detailed explanations. The room was clean, quiet, and private. I received my results within 48 hours with a follow up email from Manny. Highly recommend.”
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Common Questions
When blood pressure remains elevated despite taking two or more medications, the condition is called resistant hypertension. One of the most common and treatable causes is renal artery stenosis — a narrowing of the arteries that supply the kidneys. When the kidneys receive reduced blood flow, they signal the body to raise blood pressure further. A renal artery duplex ultrasound can identify this condition non-invasively.
Yes — and this relationship is often reversed in people's minds. Renal artery stenosis reduces blood flow to the kidneys, triggering the release of hormones that raise blood pressure system-wide. This cycle can be difficult to break with medication alone. Identifying the underlying vascular cause is the first step toward targeted treatment.
Renal artery stenosis is a narrowing of one or both arteries that deliver blood to the kidneys. It is most commonly caused by atherosclerosis (plaque buildup) in older adults, or by fibromuscular dysplasia in younger patients. A renal artery duplex ultrasound is the standard non-invasive test to detect stenosis before it causes irreversible kidney damage.
Yes. BlackPoint Diagnostics does not require a physician referral. Book directly at our online booking page — evenings after 7pm and weekends. Results reviewed by a board-certified cardiologist and delivered within 24—48 hours.
$397 flat — no facility fees, no hidden costs. We come to your home, workplace, or preferred location in Southern Maine.
Book Your Scan
$397 all-inclusive. No referral, no insurance, no facility fees. We come to you across Southern Maine.
Further Reading & References
Resistant Hypertension and Renal Artery Screening in Maine · Resistant Hypertension — Could Your Kidneys Be the Cause? · check your cardiovascular risk score · Download our free heart health guide