A Guide to Surviving an NRC Inspection

Sep 23,2022 Leave a comment Nuclear Medicine

A Nuclear Medicine Technologist’s Guide to Surviving an NRC Inspection

As a CNMT, or Nuclear Medicine Technologist, you have many responsibilities in your job. You’re preparing and administering radioactive substances, helping patients during test procedures, and ensuring a safe working environment for yourself and those around you.

The one aspect of the job that many Nuclear Medicine Technologists dread is a facility or site inspection from the NRC, or Nuclear Regulatory Commission.

Watch the video above on our YouTube channel as Eric walks you through five tips for preparing and surviving an NRC inspection

What Is The NRC?

The NRC or Nuclear Regulatory Commission is the governmental regulatory body ensuring public safety and industry standards for all uses of nuclear and radioactive materials and processes within the United States. This includes academic, medical, and industrial usage of radioactive products.

How Often Can You Expect An Inspection From The Nuclear Regulatory Commission?

The Nuclear Regulatory Commission has several regional offices. The NRC usually conducts unannounced inspections periodically for licensed activities. The inspector identifies whether the licensees are performing activities in accordance with the regulatory and license requirements. The results of the inspection are provided to the facility in written form. The report may contain enforceable actions or follow up items for re-inspection. All NRC inspection reports are also made available to the public through its electronic document retrieval system.

How To Survive An NRC Inspection

There are several key things to remember when remaining prepared for an NRC inspection. Here are our top five tips:

Tip #1: Keep Good Records

Remember that your inspection starts before the inspector ever arrives. Maintaining good records and keeping them all in one location will make it easier for the inspector to review your radiation safety program and associated documentation.

Examples of required regulatory documents can include:
• Surveys
• Leak tests
• Sealed source inventory lists
• Dosimetry records
• Internal written directives
• Radioactive waste records
• Radiation safety committee meeting minutes
• Well counter quality control reports
• Survey meter calibration certificates

Having all records clearly organized can help the inspection process go more smoothly for the NRC inspector. If you make the process go efficiently for the inspector, they’re more likely to go through your records a bit more quickly and move on to other parts of the inspection.

Tip #2: Be Truthful

It’s essential that you’re truthful with the inspector. There are really bad things that can happen if you’re not truthful with the inspector, particularly if you knowingly and willingly providing false documentation or false records.

However, you also don’t want to overshare. So only give the inspector the records that they’re asking for and let them see the processes that they want to see. This will help your inspection process go more effortlessly.

Tip #3: Practice Good Radiation Safety Techniques

While it’s important at all times to practice good radiation safety techniques, it’s particularly critical in front of an NRC inspector.

Here is a reminder of several important radiation safety techniques:
• Use syringe shields
• Draw up doses behind an L block
• Assay doses in the dose calibrator
• Wear your lab coat
• Wear protective gloves
• Be sure to wear your own dosimeter

Tip #4: Secure All Radioactive Materials

Make sure to secure all radioactive materials. What does that mean?

Here are a few examples:
• Keep your hot lab door closed
• When drawing up doses in preparation of a later injection, keep them safe in a secured room or under constant surveillance

Tip #5: Be Confident

No one knows your department like you know your department. You know everything that is going on within your department. You know where your records are at. You know where you have processes that you could improve upon. So be confident in what you are presenting to the inspector. And if you’re running a good radiation safety program, the inspection should go very smoothly.

Implementing these five tips in your nuclear medicine department can help ensure an efficient and painless NRC inspection. If you have questions or comments about any of the ways that you can best prepare for an NRC inspection or a state inspection if you’re in Agreement State, feel free to drop us a comment or send us an email. We’ll be happy to take a look at your program and figure out ways that you can be best prepared for your next regulatory inspection.

Your medical physicist is a great resource for you when designing your Radiation Safety Program. You can also always reach out to us if you have questions or want more information on Radiation Safety or want to see why you should partner with us. We also offer Radiation Safety Officer Services, Radiation Dose Optimization, and Health Physics Services.

Contact Us for a No Obligation Quote

253-254-6988

Request a Call Back

How to Evaluate a SMPTE Pattern

Sep 17,2022 Leave a comment Quality Control

What is a SMPTE pattern?

SMPTE is an acronym that stands for the Society of Motion Picture and Television Engineers. It’s a test pattern used in medical imaging to evaluate the quality of the imaging monitors.

Watch the video above on our YouTube channel as Eric walks you through how to evaluate a SMPTE pattern when completing your monthly visual quality control checklist for CT scanners.

So, why is this important to understand?

First, visually inspecting the SMPTE pattern can identify any problems with the quality of the imaging monitor. As a radiologic technologist, it’s critical that the monitor is providing consistent and accurate results.

Second, checking the SMPTE pattern on a CT scanner is part of the monthly visual quality control checklist for the scanner required by the ACR or the American College of Radiology.

On page 48 of the ACT CT Quality Control Manual, available here, they provide the specific procedures for testing the gray level performance of CT scanner acquisition display monitor.

You can also download the ACR CT Equipment Quality Control Data Form to record your daily and monthly inspections.

What do you need to look for?

There are three main areas to visually check when inspecting the SMPTE pattern on the imaging monitor.

1. The 5% patch

You want to be able to clearly identify the 5% patch within the 0%-5% square, ensuring it’s discernible.

The 5% patch is found directly to the right of the 0% gray level box, which is solid black.

2. The 95% patch

You want to be able to clearly identify the 95% patch within the 95%-100% square, ensuring it’s discernible.

The 95% patch is found directly to the left of the 100% gray level box, which is solid white.

Each of these patches must be discernible in order to pass the monthly quality control check.

3. The gray level steps

You can identify the distinct gray level steps throughout the SMPTE pattern.

On the SMPTE pattern, you should be able to identify eleven (11) distinct gray scale boxes from solid black to solid white.

There are also two (2) boxes of 50% gray – both of these squares should be identical.

On the right hand side of the ACR CT Equipment Quality Control Data Form you will find a box for the Monthly Display Monitor Gray Level.

As you check each of the three above areas, indicate its passing with a checkmark or “P” for Pass. For a failing test, you may enter “F” for Fail.

What do you do if you can't see those patches? Or you don't have distinct grade level steps?

Here are several tips:

Ensure you use the same lighting conditions every time you evaluate the SMPTE pattern for your monthly visual inspection.
Ensure that the monitor is positioned so that there’s no glare from existing lighting or excessive ambient light.
Ensure that the monitor hasn’t entered an automatic power-saver or economy mode.
A common issue is incorrect adjustment of the monitor’s contrast and brightness settings. If you suspect this may be the case, perform the manufacturer’s recommended procedure for adjusting the monitor’s contrast and brightness.

If you’re still having issues seeing the distinct 5% and 95% patches or cannot observe the gray level steps after going through the above tips, you will want to contact your service engineer or medical physicist. They can provide recommendations on how to correct the issue. Alternatively, the monitor may need to be repaired or replaced.

Now that you understand what a SMPTE pattern, you can confidently evaluate it during your CT scanner monthly inspection.

If you have any questions or comments, we welcome you to reach out at info@olympichp.com

Also, check out our Resources page for further information on quality control documentation, forms, and manuals.

Your medical physicist is a great resource for you when designing your CT Scanner Quality Control Program. You can also always reach out to us if you have questions or want more information on CT Quality Control or want to see why you should partner with us. We also offer Annual CT Physics Testing.

Contact Us for a No Obligation Quote

253-254-6988

Request a Call Back

How To Perform Weekly MRI Quality Control For The ACR

Jun 13,2021 Leave a comment Quality Control

Sitting at the MRI console, I reach for the Quality Control binder. I glance at the MRI Technologist who has a look of panic and fear on their face. It’s the kind of look that says, “Please don’t look in there, I know this isn’t going to be good.” I thumb through the pages and notice weeks of missing Quality Control and a smattering of failed results. You see, I’m a physicist. And in my time reviewing Quality Control, this is a common scenario. Balancing the competing priorities in an MRI department and Quality Control can become an afterthought. Compounding the issue is that much of the guidance for performing MRI Quality Control is written by physicists for other physicists. Not for technologists. So, what makes this guide any different? Well, before I went off to be a physicist, I was a technologist myself. And I quite enjoy putting on my technologist-hat from time to time. This guide is written with straightforward, step-by-step instructions and minimal physics jargon. And we might even have a little fun along the way. With that in mind, let’s get after it.

Key Point: A well-designed, well-documented, and reliably executed quality control (QC) program is essential to consistent production of high-quality MR images and is a key component of ensuring quality and safety in the MR Environment.

What Are The Requirements?

The requirements fall into 4 basic categories. The phantom, the frequency, the tests, and the documentation.

The Phantom

There are two phantoms that are approved by the American College of Radiology (ACR). There is the Large MRI Accreditation Phantom and the Small MRI Accreditation Phantom. The Large Phantom is used for whole body scanners while the Small Phantom is used for extremity scanners. This article will focus on the Large MRI Accreditation Phantom. And if you’re in need of purchasing a phantom, check out the phantoms offered by Supertech.

The Frequency

The ACR “strongly recommends” performing QC testing on a daily basis. That’s right, I said a daily basis. While I’m sure there are sites that perform MRI QC on a daily basis, I have not run into them. The minimum QC frequency is weekly, which is what the majority of sites are doing. Stick with a weekly QC schedule and you’ll be doing brilliantly.

Pro-Tip: Schedule to perform your QC at the same time on Monday of each week. This way if scheduling issues arise, equipment fails, or you simply forget then you have additional days in the week in which you can still complete your QC requirements.

The Tests

We’re going to cover performing each test in detail in the following sections. But to give you a preview, the tests we’ll be performing are Table Position Accuracy, Center Frequency & Transmitter Gain, Geometric Accuracy, High Contrast Spatial Resolution, Low Contrast Detectability, and Artifact Evaluation. We’ll also need to perform the Visual Checklist, which has separate documentation.

The Documentation

Documentation should be done on either the Weekly MRI Quality Control Spreadsheet published by the ACR or on your own form. You can check out our own handy MRI Quality Control template where you can input your scanner information and action limits and you’ll instantly know if a test didn’t pass by highlighting your result in red. The best part is, it’s free! Additionally, the MRI Accreditation Program Visual Checklist must be completed on a weekly basis. These documents should be reviewed for completeness on an annual basis by your medical physicist.

Let's Do Some QC!

Phantom Setup

The large phantom should be positioned in the head coil so that it is in the center of the coil in the left/right and anterior/posterior direction. This is relatively easy to do using a phantom cradle for accurate and repeatable results. Alternatively, you can use a stack of computer paper to ensure the phantom is centered within the coil. Using the same stack of paper will be important to reproduce your results from week to week.

Use a level to ensure the phantom is level in all directions. Do this by placing the level on the front bar of the phantom and also on the top of the phantom.

Move the phantom into position within the scanner using the laser to complete the positioning. The laser should be positioned so that 80% of the laser is on the grid structure and 20% is off the grid structure. How do you determine if 80% of the laser is on the grid? Just aim for having the majority of the laser line on the grid and a little bit off of the grid and you’ll be fine.

Send the phantom to isocenter and you’re now ready to scan!

Scanning The Phantom

A three-plane localizer should be used to ensure the phantom is properly positioned, followed by the acquisition of a sagittal localizer. The ACR sagittal localizer sequence should use the following parameters.

Sagittal Localizer Imaging Parameters

Pulse Sequence	Spin Echo
TR	200 ms
TE	20 ms
FOV	25 cm
Number of Slices	1
Slice Thickness	20 mm
Slice Gap	N/A
NEX (Averages)	1
Matrix	256 x 256
Scan Time	51-56 seconds

Table Position Accuracy

After acquiring the sagittal localizer, review the image. You’ll need to make measurements on the Sagittal Localizer to verify the Table Position Accuracy. Each manufacturer is slightly different, but the principle is the same. Turn on the “Grid” function and you’ll have a horizontal line and a vertical line superimposed on the Sagittal Localizer. This is your X and Y axis. In this case, we don’t care about the Y axis. On the image, take a measurement from the X axis to the top of the grid structure in the phantom. The grid structure in the phantom is denoted by the 11 little vertical black lines on the image.

Another option may be to turn on the cursor and hover over the image at the top edge of the grid structure. In the example below, we can see the cursor is at a position of S 0.00 mm. This means the top edge of the grid structure is exactly at isocenter.

Action Criteria: The top edge of the grid should be within ± 5mm of isocenter.

If the location of the top edge of the grid structure is within ±5 mm of isocenter, enter “YES” in the column designated “Accuracy OK?”

If the computer booted without a problem and the scanner interface works properly, enter a “YES” in the column designated as “Console OK?”

Fill in Columns 2 & 3 of the Weekly MRI Quality Control Spreadsheet.

Center Frequency and Transmitter Gain

The Center Frequency and Transmitter Gain of the ACR T1 protocol must be documented on the QC Form. The ACR T1 protocol should use the following parameters.

ACR T1 Imaging Parameters

Pulse Sequence	Spin Echo
TR	500 ms
TE	20 ms
FOV	25 cm
Number of Slices	11
Slice Thickness	5 mm
Slice Gap	5 mm
NEX (Averages)	1
Matrix	256 x 256
Scan Time	~ 2:10

The ACR T1 protocol should be used to scan the phantom in 11 slices. The scan range should be placed right between the two 45⁰ wedges placed in the phantom. See figure to the right.

Action Criteria: The Larmor Frequency is about 64 MHz for a 1.5T scanner and 128 MHz for a 3T scanner. This means the action limit for 1.5T scanners is a week to week change of ± 128 Hz. The action limit for 3T scanners is a week to week change of ± 256 Hz. Recording the last 4 digits of the Center Frequency in Hz is fine. For Transmit Gain, we typically set a baseline by taking an average after a series of 10 measurements and set action limits of ±20% from baseline. You should consult with your medical physicist when setting the baseline values and action limits for the Center Frequency and Transmit Gain.

Fill in Columns 4 & 5 of the Weekly MRI Quality Control Spreadsheet.

Geometric Accuracy Measurements

Geometric Accuracy is measured using the Sagittal Localizer as well as Slice 5 from the ACR T1 series. It’s important to set the window width and level the same way each time. The ACR’s method for doing this is a little complicated, so we’re going to break this down.

Step 1: Set the window width to 0 or 1.
Step 2: Adjust the window level until one half of the image is white and the other half is black. It’s OK to estimate here. Note the window level setting.
Step 3: Now adjust the window width to the same value. We want the window width and window level to be equal.
Step 4: Finally, reduce the window level value by half.

Example: Bring your window width to 0. Adjusting the window level until half the image is white and half is black you note the window level is at ~1400. Now you adjust the window width to also be ~1400. Finally, take you window level to ~700 and you’re ready to make your measurements!

Proceed with making geometric accuracy measurements on the image(s). For the Sagittal Localizer image, you’ll make a measurement in the Head/Foot direction (top to bottom). Then for Slice 5 on the ACR T1 protocol, you’ll make measurements in the Anterior/Posterior direction and in the Right/Left direction.

Action Criteria: Your measurements should be within ± 2mm of their true values.

Fill in Columns 6, 7 & 8 of the Weekly MRI Quality Control Spreadsheet.

High Contrast Spatial Resolution

Now we’re ready to move on to High Contrast Spatial Resolution. We’re going to simplify this and just call this resolution. Resolution is measured using Slice 1 of the ACR T1 images series. The resolution insert consists of three resolution targets with an upper-left (UL) and lower-right (LR) and share one hole in common at the corner where they meet. The diameter of the left target is 1.1 mm, the center target is 1.0 mm, and the right target is 0.9 mm.

Zoom in on the image so that you can see the resolution targets. Then adjust the window width and level until the holes in the resolution insert can best be seen. The upper-left array is used to assess resolution in the horizontal direction. To do this, look at the rows in the upper-left array to see if all four holes in any single row are distinguishable from one another. The smallest target with an entire row as distinguishable should be recorded as the resolution for the upper-left (UL) array.

Repeat the same steps for the lower-right array in the vertical direction by looking at the columns in the lower-right array to see if all four holes in any single column are distinguishable from one another. The smallest target with an entire column as distinguishable should be recorded as the resolution for the lower-right (LR) array.

So what exactly does distinguishable mean? To be observed as distinguishable, the image intensity does not need to drop to zero between the holes; that would not be normal. However, the window width and level setting should allow all four holes in at least one row (UL) or one column (LR) as recognizable points of brighter signal intensity than the spaces between them. When the holes size is comparable to the resolution in the images, there is a tendency for groups of two or more holes in a row or column to blur together and appear as a single irregularly shaped spot of signal. In this case the holes in that row or column would be considered unresolved.

Let’s look at an example…

In the example above we can see every row in the upper-left array and every column in the lower-right array for the 1.0 mm targets. When we look at the 0.9 mm targets, we can distinguish 2 rows in the upper-left array and 2 columns in the lower-right array. Because we only need to see at least one row and one column to call a target visualized, we would enter 0.9 mm into our spreadsheet for Columns 9 and 10.

Action Criteria: You should be able to visualize at least the 1.0 mm target.

Fill in Columns 9 & 10 of the Weekly MRI Quality Control Spreadsheet.

Low Contrast Detectability

Low Contrast Detectability (LCD) is evaluated in slices 8-11 of the ACR T1 series. In each slice, the low-contrast objects appear as a row of small disks radiating from the center of the phantom like spokes on a wheel. Each spoke is made up of 3 discs, and there are 10 spokes in each circle. The contrast values increase as you go from slice 8 to slice 11. The measurements for this test consists of counting the number of complete spokes seen in a designated axial slices. Which slice is the designate slice? The most appropriate slice for evaluation should be set by your medical physicist. However, general guidance for determining the appropriate slice is to use the lowest contrast slice where some spokes are not visualized. This is often Slice 8.

Display the slice to be scored using a window width and level setting for best visibility of the low contrast objects. Count the number of spokes seen beginning with the 12 o’clock position and working clockwise. The number of complete spokes where all three discs are discernible from background is the score for that slice.

Action Criteria: The action criteria for low contrast should be set by your medical physicist.

Artifact Evaluation

Artifact Evaluation should be performed on each slice of the ACR T1 series. The window width and level should be adjusted so that a full range of pixel values can be observed in the image; the image should have varying levels of gray and should not be all black or all white. When evaluating the phantom for artifacts, you should make sure

The phantom appears circular, not elliptical or otherwise distorted.
There are no ghost images of the phantom in the background or overlying the phantom image.
There are no streaks or artifactual bright or dark spots in the image.
There are no unusual or new features in the image.

Action Criteria: The images should be free of artifacts. If you have artifacts in the image, you should contact your service engineer or medical physicist.

MRI Accreditation Program Visual Checklist

On a weekly basis, the MRI Visual Checklist should be completed to verify the MRI system patient bed transport, alignment and system indicator lights, RF room integrity, emergency cart, safety lights, signage, and monitors are present and working properly and are mechanically and electrically stable.

Documentation is performed on a separate Visual Checklist sheet. You can download a copy here.

Each of the items listed in the visual checklist should pass or receive a checkmark. Items not passing the visual checklist should be replaced or corrected immediately. Items missing from the room should be replaced immediately. Malfunctioning equipment should be reported to the MRI service engineer for repair or replacement as soon as possible.

Wrapping Up

If you’ve made it this far, congratulations! You’ve successfully made it through all of the required steps for performing MRI Quality Control. A couple of key takeaways

Perform MRI QC on a weekly basis
Follow the steps in this guide
Document your results

And that’s it. You’re now well on your way to a well-executed quality control program and passing all of your ACR inspections like a breeze!

Your medical physicist is a great resource for you when designing your MRI Quality Control Program. You can also always reach out to us if you have questions or want more information on MRI Quality Control or want to see why you should partner with us. We also offer Annual MRI Physics Testing and MRI Safety Audits.

Contact Us for a No Obligation Quote

253-254-6988

Request a Call Back