US Kidneys — Dictation, Appropriateness, and Dose for Residents

1. The Stat Renal Ultrasound: Beyond “Normal” vs. “Abnormal”

It’s 3 PM on a Tuesday. The ED calls with a stat renal ultrasound for acute kidney injury. The nephrology fellow is waiting for your read to decide on the next steps, and your attending expects a report that clearly states the size, cortical echogenicity relative to the liver, and any degree of hydronephrosis. Just dictating “no hydronephrosis” isn’t enough; they want the details that point toward or away from an obstructive cause versus intrinsic medical renal disease. Getting this right, quickly and consistently, is key. When you’re juggling a busy list, having a solid framework is everything. For more tools like this, check out the residents and fellows resource hub, which has a bunch of free trainee calculators and references.

2. What a Renal Ultrasound Covers and What Attendings Look For

A bilateral renal ultrasound is the workhorse for evaluating the renal parenchyma and collecting systems without radiation. It’s the first-line study for a huge range of clinical questions.

Common indications you’ll see on the order:
* Acute or chronic renal failure
* Hematuria
* Suspected hydronephrosis or urinary obstruction
* Initial evaluation of a potential renal mass
* Renal transplant follow-up and evaluation for dysfunction
* Screening for polycystic kidney disease

Your attending expects a systematic evaluation in the report. They’re looking for you to comment on:
* **Kidney Size:** A long-axis measurement for each kidney (normal is typically 9-13 cm).
* **Parenchymal Echogenicity:** Is the renal cortex hypoechoic (darker) than the adjacent liver or spleen, as it should be? Increased echogenicity points to medical renal disease.
* **Corticomedullary Differentiation:** Can you distinguish the cortex from the medullary pyramids? Loss of this distinction is a sign of disease.
* **Hydronephrosis:** Is the collecting system dilated? If so, it needs to be graded (mild, moderate, or severe).
* **Focal Lesions:** Are there any cysts or solid masses? Simple cysts need to be described as such (anechoic, posterior acoustic enhancement, smooth walls). Complex masses need a recommendation for CT or MRI.
* **Urinary Bladder:** Check for wall thickening, masses, stones, and measure the post-void residual volume if indicated.

3. Radiology Report Template for a Bilateral Renal Ultrasound

Use this template as a starting point for your macros. It covers the key elements for a comprehensive report that your attendings will appreciate.

Technique

Real-time grayscale and color Doppler ultrasound evaluation of the kidneys and urinary bladder was performed using a curved array transducer. Representative images were archived.

Findings

RIGHT KIDNEY:
The right kidney measures [length] x [AP] x [transverse] cm.
The renal parenchyma is [normal in echogenicity / increased in echogenicity] compared to the adjacent liver.
Corticomedullary differentiation is [preserved / effaced / lost].
The cortical thickness is [normal / thinned].
There is [no hydronephrosis or hydroureter / mild / moderate / severe hydronephrosis].
No discrete renal mass, cyst, or calculus is identified.
Color Doppler imaging demonstrates normal vascular flow.

LEFT KIDNEY:
The left kidney measures [length] x [AP] x [transverse] cm.
The renal parenchyma is [normal in echogenicity / increased in echogenicity] compared to the adjacent spleen.
Corticomedullary differentiation is [preserved / effaced / lost].
The cortical thickness is [normal / thinned].
There is [no hydronephrosis or hydroureter / mild / moderate / severe hydronephrosis].
No discrete renal mass, cyst, or calculus is identified.
Color Doppler imaging demonstrates normal vascular flow.

URINARY BLADDER:
The urinary bladder is [distended / partially distended / empty]. The bladder wall appears [normal in thickness / diffusely thickened]. No intraluminal mass, calculus, or other abnormality is seen.
Post-void residual volume, if measured, is [X] mL.

Impression

1. [e.g., Normal bilateral renal ultrasound.]
OR
1. [e.g., Bilateral increased renal parenchymal echogenicity, suggestive of medical renal disease.]
2. [e.g., No evidence of hydronephrosis to suggest an obstructive uropathy.]

4. Free Template Sources for Your Personal Library

Building a personal library of high-quality templates is one of the best things you can do as a trainee. Beyond the macros you build yourself, two great free repositories exist that are worth bookmarking:

• RadReport.org: This is the RSNA-curated library. It’s comprehensive, peer-reviewed, and covers nearly every modality and subspecialty. It’s an excellent source for standardized, best-practice templates.
• Radiology Templates (AU): Maintained by Australian radiologists, this site offers a fantastic collection of practical, easy-to-use templates that are great for on-call and daily use.

These are solid resources built by and for radiologists, and they can save you a ton of time.

5. The Next-Level Move: From Free-Form Dictation to Structured Report

The template above is a great starting point. But on a busy service, you’re often dictating positive findings on the fly. You see a dilated collecting system and say, “Left kidney shows moderate hydronephrosis with some mild cortical thinning.” You see a simple cyst and describe it. The challenge is then manually structuring those free-form findings back into a clean, organized report that hits all the required elements.

This is where AI-powered tools can streamline your workflow. Instead of toggling between your dictation and a template, you can dictate your findings naturally. GigHz Precision AI is designed to listen to your free-form dictation of positive findings and automatically generate a complete, structured report. It uses pre-loaded templates from governing bodies like the ACR and SIR, ensuring your report is compliant and comprehensive. It also helps surface the appropriate Clinical Decision Support (CDS) when needed for specific findings, like classifying a renal mass with Bosniak criteria, guiding you to the right conclusion without having to stop and look it up.

6. When Should You Order a Renal Ultrasound? ACR Appropriateness Criteria

Knowing when an exam is indicated is just as important as knowing how to read it. The American College of Radiology (ACR) provides evidence-based guidelines. For a renal ultrasound, here are some key scenarios.

For a patient with suspected acute pyelonephritis, the ACR guidance varies. In an uncomplicated, first-time presentation, imaging may not be necessary. However, for a complicated patient (e.g., with diabetes, immune compromise, or failure to respond to therapy), a renal US is rated as Usually Appropriate. The same Usually Appropriate rating applies to patients with a history of stones, obstruction, or pregnancy.

In the workup of hematuria, a renal US is Usually Appropriate for microhematuria (with or without risk factors) and for gross hematuria as an initial imaging step. It’s also the first-line choice for microhematuria in a pregnant patient. While a full workup for hematuria in a high-risk patient often requires a CT urogram, the ultrasound is a fantastic non-radiation starting point.

For evaluating renal failure and renal transplant dysfunction, a renal ultrasound is the definitive first-line imaging test and is rated Usually Appropriate. It provides crucial information on kidney size, parenchymal health, and the presence of any obstruction that could be causing the dysfunction.

Alternatives like CT abdomen/pelvis, CT urogram, and MRI are often used for definitive characterization of masses or full evaluation of the ureters, but ultrasound remains the go-to initial study for these common renal indications.

7. Renal Ultrasound Protocol — Key Views and Technical Parameters

A standard renal ultrasound protocol is straightforward but requires systematic image acquisition to be complete. You’ll use a low-frequency (1-9 MHz) curved array transducer to get the necessary penetration.

The essential images include:

• Long-Axis Views: A long-axis (sagittal) view of both the right and left kidneys, including a measurement of the maximum length. This is the most important measurement for assessing size and chronicity.
• Transverse Views: Transverse (axial) views of the upper pole, mid-pole, and lower pole of each kidney.
• Comparison Views: Images demonstrating the echogenicity of the right kidney cortex relative to the liver and the left kidney cortex relative to the spleen.
• Urinary Bladder: Transverse and sagittal views of the bladder to assess for wall thickening, masses, or stones. A post-void residual volume should be calculated if obstruction or retention is a concern.
• Doppler Imaging: Color Doppler should be used to confirm patency of the main renal arteries and veins. Spectral Doppler with Resistive Index (RI) measurement is performed when evaluating for parenchymal disease or renovascular hypertension. An RI >0.7 is considered elevated.

A common pitfall is incomplete visualization of the left kidney due to overlying bowel gas. Having the patient roll into a right lateral decubitus position can use the spleen as an acoustic window and significantly improve your images. Another is forgetting to check the bladder, which can reveal the cause of bilateral hydronephrosis (e.g., an enlarged prostate or bladder outlet obstruction).

8. 3+ Months Free for Radiology Residents and Fellows

If you want to look like a rockstar on your reports, we’re offering an extended free trial of GigHz Precision AI specifically for trainees. The idea is simple: you dictate your positive findings in free form, and the AI generates a clean, structured report using ACR and SIR templates, with the appropriate clinical decision support firing automatically.

All we ask in return is your feedback so we can keep improving the product for residents and fellows on the ground.

To sign up, we just need three things:

1. Your PGY year (e.g., PGY-2, PGY-4)
2. Your training type (radiology residency or fellowship specialty)
3. Your training program / hospital name

There’s no credit card required and no long forms. Just reply to the application with those three items, and we’ll get you set up. You can apply for the residents free-access program here.

9. Frequently Asked Questions

Is GigHz Precision AI HIPAA-compliant?

Yes. The platform is designed for de-identified workflows by default. It processes the clinical content of your dictation without requiring or storing patient-identifying information (PHI). All data is encrypted in transit and at rest.

Do I need our hospital’s IT department to set this up?

No. GigHz Precision AI is browser-based and requires no local software installation or special permissions. It works on any modern computer, including the workstations in the reading room or your personal laptop or iPad at home.

Does it work with PowerScribe or other dictation systems?

Yes. It works alongside your existing dictation system. You dictate as you normally would, and the AI tool works in a separate browser window to help you structure the report. You can then copy and paste the final, structured report into your PACS/RIS.

Can I use this on my phone or iPad on call?

Absolutely. The platform is fully responsive and designed to work on mobile devices, making it easy to use on a call-room iPad or your personal phone when you need to quickly reference a template or classification system.

Can I customize the templates?

Yes. While the system comes pre-loaded with standardized templates from the ACR, SIR, and other societies, you can create, modify, and save your own templates and macros to match your personal preferences or your institution’s specific requirements.

What happens after my residency or fellowship ends?

We offer continuity plans for graduating trainees who want to continue using the platform in their practice. Your customized templates and settings will be saved to your account, ready for you on day one as an attending.

Free GigHz Tools That Pair With This Article

Three free tools that complement the material above:

• ACR Appropriateness Criteria Lookup — Type an indication or clinical scenario in plain language and get the imaging studies the ACR rates for it, with adult and pediatric radiation levels. Built directly from 297 ACR topics, 1,336 clinical variants, and 15,823 procedure ratings.
• GigHz Imaging Protocol Library — A searchable library of 131 imaging protocols with the physics specs surfaced and the matching ACR Appropriateness Criteria alongside. Plain-English narratives readable in 60 seconds, organized by modality.
• GigHz Radiation Dose Calculator — Pick the imaging studies a patient has had and see total dose in millisieverts (mSv) with comparisons to natural background radiation, transatlantic flights, and chest X-rays. Useful for shared decision-making.

Reviewed by Pouyan Golshani, MD, Interventional Radiologist — May 7, 2026