When is nt scan done

Nuchal translucency test Information | Mount Sinai

Nuchal translucency screening; NT; Nuchal fold test; Nuchal fold scan; Prenatal genetic screening; Down syndrome - nuchal translucency

The nuchal translucency test measures the nuchal fold thickness. This is an area of tissue at the back of an unborn baby's neck. Measuring this thickness helps assess the risk for Down syndrome and other genetic problems in the baby.

How the Test is Performed

Your health care provider uses abdominal ultrasound (not vaginal) to measure the nuchal fold. All unborn babies have some fluid at the back of their neck. In a baby with Down syndrome or other genetic disorders, there is more fluid than normal. This makes the space look thicker.

A blood test of the mother is also done. Together, these two tests will tell if the baby could have Down syndrome or another genetic disorder.

How to Prepare for the Test

Having a full bladder will give the best ultrasound picture. You may be asked to drink 2 to 3 glasses of liquid an hour before the test. DO NOT urinate before your ultrasound.

How the Test will Feel

You may have some discomfort from pressure on your bladder during the ultrasound. The gel used during the test may feel slightly cold and wet. You will not feel the ultrasound waves.

Why the Test is Performed

Your provider may advise this test to screen your baby for Down syndrome. Many pregnant women decide to have this test.

Nuchal translucency is usually done between the 11th and 14th week of pregnancy. It can be done earlier in pregnancy than amniocentesis. This is another test that checks for birth defects.

Normal Results

A normal amount of fluid in the back of the neck during ultrasound means it is very unlikely your baby has Down syndrome or another genetic disorder.

Nuchal translucency measurement increases with gestational age. This is the period between conception and birth. The higher the measurement compared to babies the same gestational age, the higher the risk is for certain genetic disorders.

The measurements below are considered low risk for genetic disorders:

At 11 weeks -- up to 2 mm
At 13 weeks, 6 days -- up to 2.8 mm

What Abnormal Results Mean

More fluid than normal in the back of the neck means there is a higher risk for Down syndrome, trisomy 18, trisomy 13, Turner syndrome, or congenital heart disease. But it does not tell for certain that the baby has Down syndrome or another genetic disorder.

If the result is abnormal, other tests can be done. Most of the time, the other test done is amniocentesis.

Risks

There are no known risks from ultrasound.

Driscoll DA, Simpson JL. Genetic screening and diagnosis. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Philadelphia, PA: Elsevier; 2021:chap 10.

Walsh JM, D'Alton ME. Nuchal translucency. In: Copel JA, D'Alton ME, Feltovich H, et al, eds. Obstetric Imaging: Fetal Diagnosis and Care. 2nd ed. Philadelphia, PA: Elsevier; 2018:chap 45.

Last reviewed on: 3/31/2020

Reviewed by: John D. Jacobson, MD, Professor of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda Center for Fertility, Loma Linda, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

Nuchal translucency test (NT scan)

Pregnancy
Health & Safety

By Kate Marple

August 9, 2021

The NT scan is an ultrasound done in the first trimester to determine your baby's risk of having Down syndrome and some other chromosomal abnormalities. It's usually done along with a blood test. If the nuchal translucency test indicates that your baby may have a health condition, you can decide whether to have a diagnostic test to find out for certain.

Photo credit: Thinkstock

What is the nuchal translucency test?
How is the nuchal translucency test done?
How are NT scan results calculated?
What do NT scan results mean?
How accurate is the nuchal translucency test?
What happens if my NT scan indicates a problem?

What is the nuchal translucency test?

The nuchal translucency test (also called the NT scan) uses ultrasound to assess your developing baby's risk of having Down syndrome (DS) and some other chromosomal abnormalities, as well as major congenital heart problems. It's offered to all pregnant women, along with a blood test, in first-trimester combined screening options.

The NT scan measures the clear (translucent) space in the tissue at the back of your baby's neck. (This is the "nuchal translucency.") Babies with abnormalities tend to accumulate more fluid at the back of their neck during the first trimester, causing this clear space to be larger than average.

The NT scan must be done when you're between 11 and 14 weeks pregnant, because this is when the base of your baby's neck is still transparent. (The last day you can have it is the day you turn 13 weeks and 6 days pregnant.)

Some practitioners also look for the presence of the fetal nasal bone during the NT scan. If no nasal bone is seen in the developing baby, some experts believe this increases the likelihood of chromosomal abnormalities. In some very specialized testing centers, other major abnormalities may be detected during the scan.

The NT scan is not invasive, and it's not conclusive. Diagnostic testing such as CVS or amniocentesis are necessary to confirm a positive screen result.

In addition to testing for Down syndrome (trisomy 21), the NT scan will also screen for:

Trisomy 18 (Edward's syndrome)
Trisomy 13 (Patau syndrome)
Some other chromosomal abnormalities
Some structural problems, such as heart, abdominal wall, and skeletal defects

If your baby's nuchal translucency measurement indicates that they are at increased risk for structural defects, you'll be given a special ultrasound (also called an advanced level or level II ultrasound) and a special test called a fetal echocardiogram, both in the second trimester. If your baby has a structural defect, they'll need to be monitored with regular ultrasounds and delivered at a medical center equipped to handle the condition.

How is the nuchal translucency test done?

The sonographer first confirms your baby's gestational age by measuring them from crown to rump to see whether they're about the size they should be for their age. Then the sonographer positions the sensor, called the transducer, over your abdomen so that your baby's nuchal translucency shows up on the monitor and measures the thickness of it on the screen with calipers.

How are NT scan results calculated?

Your baby's chances of having a chromosomal abnormality are determined by the nuchal translucency measurement, your age, your baby's gestational age, and the blood test results.

Your age is factored in because although anyone can have a baby with a chromosomal abnormality, the risk increases as you age. For example, your likelihood of carrying a baby with Down syndrome ranges from approximately 1 in 1,200 at age 25 to 1 in 100 at age 40.

Because a baby's nuchal translucency normally gets a bit thicker with each day of gestation, researchers have been able to establish how large the translucent area should be each day during the three weeks the screening can be performed.

They've also calculated the statistical relationship between this measurement, the baby's age, the mother's age, and the likelihood that the baby will be born with certain abnormalities. In general, the thicker the nuchal translucency at a given gestational age, the higher the chance of a chromosomal problem.

You may get the results right away, or you may have to wait up to 10 days if the doctor has to send the data to a processing center.

What do NT scan results mean?

You'll want to talk with your practitioner or a genetic counselor about how to interpret the results, which can be confusing. Many centers will report each individual lab result as well as the final calculated result using a special formula.

The ratio

You'll get your results in the form of a ratio that expresses your baby's chances of having a chromosomal defect.

For example, a risk of 1 in 100 means that for every 100 women with this result, one baby will have Down syndrome and 99 will not. A risk of 1 in 1,200 means that for every 1,200 women with this result, one baby will have it and 1,199 will not. The higher the second number, the lower the risk.

Normal or abnormal results

You may also be told that your results are "normal" or "abnormal" for a particular condition, depending on whether the ratio is below or above a specified cutoff. For example, some tests use a cutoff of 1 in 250. So a result of 1 in 1,200 would be considered normal because the risk that there's a problem is lower than 1 in 250. A ratio of 1 in 100 would be considered abnormal because that risk is higher than 1 in 250.

Remember that a normal screening result (screen negative) isn't a guarantee that your baby has normal chromosomes, but it does suggest that a problem is unlikely. Likewise, an abnormal screening result (screen positive) doesn't mean that your baby has a chromosomal problem – just that your baby is more likely to have one. Most screen-positive babies turn out not to have a problem: Only about a third of babies with an increased nuchal translucency measurement turn out to have chromosomal defects.

How accurate is the nuchal translucency test?

The NT scan alone will detect about 70 to 80 percent of babies with DS (depending on which study you look at). The detection rate for the NT scan plus a first-trimester blood test ranges from 79 to 90 percent. (Most tests will include both the NT scan and the blood test.)

This does not mean that a screen-positive baby has a 79 to 90 percent chance of having DS. It just means that 79 to 90 percent of babies who have DS will have screening results that are suspicious enough to recommend diagnostic testing. And 5 to 21 percent of babies who have DS will be determined to be at normal risk — that is, the results will be misleading.

False negative result

Screening tests aren't perfect. They don't detect all cases of DS, so they may identify your baby as being at low risk when they really do have DS.

In other words, if you're carrying a baby with DS, there's a 79 to 90 percent chance that the combined screening will detect the abnormality and give you what's called a screen-positive result indicating that further testing is recommended. But it also means there's a 5 to 21 percent chance that the tests will miss the DS and give you a screen-negative result.

This is called a false negative result, and it might lead you to decide against diagnostic testing that would have revealed a problem.

False positive result

These tests also have a 5 percent false-positive rate. A false-positive result is one that suggests that your baby is at increased risk for DS or another condition when, in fact, there's no problem.

What happens if my NT scan indicates a problem?

With the help of your practitioner or a genetic counselor, you'll want to decide whether the results indicate a high enough risk that you want to have CVS or amniocentesis to get a definitive diagnosis.

In making your decision, you'll need to weigh your need to know about your baby's condition against the small chance that diagnostic testing could cause a miscarriage.

If you decide not to have diagnostic testing, you can get more information about your baby's health and development by following up with NIPT (a blood test that's available to all pregnant women beginning at 10 weeks of pregnancy), the quad screen (a blood test in the second trimester), and a detailed ultrasound at 18 to 20 weeks.

This ultrasound can detect "soft markers" of chromosome disorders, such as short limbs, a bright dot in the heart, a bright bowel, and certain problems in the kidneys. It can also look for anatomical defects, such as spina bifida.

Sources

BabyCenter's editorial team is committed to providing the most helpful and trustworthy pregnancy and parenting information in the world. When creating and updating content, we rely on credible sources: respected health organizations, professional groups of doctors and other experts, and published studies in peer-reviewed journals. We believe you should always know the source of the information you're seeing. Learn more about our editorial and medical review policies.

ACOG. 2020. Prenatal genetic screening tests. American College of Obstetricians and Gynecologists. https://www.acog.org/patient-resources/faqs/pregnancy/prenatal-genetic-screening-tests [Accessed August 2021]

March of Dimes. 2020. Down syndrome. https://www.marchofdimes.org/complications/down-syndrome.aspx [Accessed August 2021]

MedlinePlus. 2021. Nuchal translucency test. https://medlineplus.gov/ency/article/007561.htm [Accessed August 2021]

Nemours. 2015. Down syndrome. https://kidshealth.org/en/parents/down-syndrome.html?ref=search [Accessed August 2021]

NIH. 2017. What tests might I need during pregnancy? National Institute of Child Health and Human Development. https://www.nichd.nih.gov/health/topics/preconceptioncare/conditioninfo/tests-needed [Accessed August 2021]

UptoDate. 2021. Should I have a screening test for Down syndrome during pregnancy? https://www. uptodate.com/contents/should-i-have-a-screening-test-for-down-syndrome-during-pregnancy-beyond-the-basics?topicRef=422&source=see_link [Accessed August 2021]

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what to do to solve the problem

Simple fix for the problem
Hardware reasons
Wi-Fi connection problems
Typical problems specific to the MFP
Software reasons
Additionally

The diagnosis of the reason why the scanner does not work should be carried out in stages and depends on whether scanning stopped after some time or the scanner did not start immediately after connection.

It also depends on the technique itself. If the MFP does not scan, then the problem may additionally lie in an uninstalled driver for the device. Often there are cases when the printer itself works, printing is performed, but refuses to transfer information to a computer.

Simple fix

Rebooting the entire system can sometimes solve the problem. Turn off your computer and MFP or standalone scanner. Disconnect from the computer and unplug the cable from the outlet. Wait 1-2 minutes for the memory of both devices to reset. Then again, turn on the network.

Start the computer and MFP (scanner), try to scan. If it worked, then there was a one-time failure, which in the future can be solved in the same way. If the problem occurs too often, it is recommended to contact the service center.

Similar failures may occur if the printer is plugged into an outlet that is also connected to other devices with periodic on / off (refrigerators, air conditioners, etc. ).

Hardware reasons

First check if the machine is connected to the computer. Go to the "Devices and Printers" window. To do this, simultaneously press the key combination "Windows + R" on the keyboard. Next, run the "control printers" command.

The required scanner or printer must be in the equipment list.

If the technique is displayed and its icon is not brightened, does not contain any warning icons nearby (for example, an exclamation mark), then everything is fine with the connection.

In addition, the device can be diagnosed for problems. Right-click on the scanner icon, select Troubleshoot.

Then follow the wizard step by step and if you find problems, try to get rid of them. If no problems are identified, and the diagnostic wizard writes that the device is working normally, then the reason is different.

The situation when the equipment icon is not in the equipment, or it is inactive at the moment, requires device diagnostics.

First make sure the scanner is turned on at all. Sometimes, due to inattention, users forget to press the power button. If, even after pressing the button, no indicators on the printer case light up, then there is no power from the network or there are problems inside the machine itself. In this case, inspect the cords.

Check for severe kinks in the wires. If they are, it is possible that the wires are damaged inside under the insulation. Then take another cable for the test and try to turn it on. The same check must be made for the USB cable that connects the printer to the computer. The easiest way is to get a new cable.
Similarly with the external power supply, which is located on the cable connecting the device to the socket. The easiest way is when there is an indicator on the block that indicates that voltage is being applied. The indicator does not light - the problem is in the block. Needs repair or replacement.

The unit is in good condition, the cords are not damaged, and the device is still turned off, which means that there is a high probability of failure of the “internal stuffing”. It is almost impossible for an inexperienced person to identify a malfunction. Only the appeal to specialists will help.

Additionally, try plugging the USB cable from the MFP into a different port on the computer. The USB input can simply fail or the driver for it may fail. In the first case, swapping the cord to another USB will help. In the second case, reinstalling the driver on USB controllers. Go to the device manager through the properties of "My Computer" and see if there are any exclamation marks next to the controllers. If available, update the drivers through the properties of a specific USB. Removing the controller and then adding it in a new way using the hardware configuration update function can help.

An outdated USB (1.1) interface can greatly affect the speed of office equipment. If the startup or scanning process is too slow, make a USB 2.0 connection.

For trouble-free connection of a computer with a peripheral device, it is not recommended to use a cord longer than one and a half meters and connect it through adapters, USB hubs.

Wi-Fi connection problems

Make sure the Wi-Fi signal is strong enough. Try reconnecting by first turning off and back on Wi-Fi on the laptop.

It is desirable that there are no devices emitting strong electromagnetic waves (microwave ovens, speakers, cordless phones, etc.) near the MFP. It is also recommended to restart the router - press the power button on the distributing device twice.

MFP specific issues

Another operation is currently in progress. For example, if sheets are printed, then the scanner is unlikely to scan. You must wait until the current operation is completed and try to scan again. The same applies to the one that needs to be cleaned. The print job was sent, but the printer did not start printing for some reason. But the task still hangs, which means that the MFP is busy with the printing process. After the scanner should work.
When there are no problems with the printer in the MFP, but the scanner does not work, the reason may be the lack of a driver specifically for the scanning device. In most cases, a generic driver is provided with the equipment or on the manufacturer's website. During its installation, all the necessary files are copied to the system for the correct operation of all MFP nodes. But sometimes for the operation of each mechanism (printer, copier or scanner) you need to install separate software. Install all driver packages from the disk. If there is no disk, download the software from the office. company website. Be sure to restart your computer for the changes to take effect.
The scanner is a stand-alone device and even if due to running out of ink, the scan will continue to work. But in some models, the operation of the entire MFP may automatically block if there are any problems, for example, the same empty cartridges. The same applies to the replacement of cartridges with new ones and their incorrect installation. The problem is easy to diagnose, just by knowing when the scan stopped running. If after manipulation with cartridges, then the reason is obvious. As a rule, if there are problems with the cartridges, the indicators on the machine body flash or a notification is displayed on the built-in display of the MFP.

Canon MFPs are experiencing a conflict between the Canon Toolbox branded software and the standard Windows Fax and Scan program. The solution is to disable the latter. Go to the control panel, then to the sections "Programs" - "Programs and Features". Then click on the "Turn Windows features on or off" link.

Find the "Print and Document Services" section, inside it, uncheck the desired item.

Restart Windows and try to scan.

Software causes

Make sure the correct device model is selected in the scan settings step. It is especially important to control this with a large number of connected printers. Windows can choose another device on its own. It is recommended that the correct machine be specified the next time you scan.
The complete absence of drivers, their damage due to viruses or other factors. The solution is to install “firewood”, check the computer for viruses, followed by treatment and reinstallation of drivers. First it is recommended, and then put from scratch. Then a reboot is performed.
Driver incompatibility with Windows version. This usually happens on outdated models of equipment for which the software is no longer updated, and Windows is constantly being improved. Scanning will then only work on another computer with a suitable OS version.
Try another scanning program. To get started, scan through the official programs from the developers. Then download software from third-party developers. It would not be superfluous to check the scanning in standard tools: "Scanner" in Win 10, "Paint". More in the article:.

Optional

Each MFP must be able to start in the so-called service mode. Instructions can be found in the user manual. Check if scanning works in this mode. Also check the operation of the copier in offline mode without connecting to a computer. The fact is that according to the principle of operation, the copier and the scanner are similar, so if the first one does not work, then the device is very likely to break down and there is no way to repair it.

Watch the indications on the MFP. Any flashing of lights or buttons may indicate a problem in the MFP, due to which all other functions are blocked. Control the errors that occur on the display of the MFP or on the computer monitor. Error codes should be discussed in the documentation for the device. After the situation is corrected, the resumption of work should occur.

As a last resort, reset the device. How to do this is written in the instructions for the MFP.

what to do with MFPs HP, Canon, Samsung, Kyocera and others

If the printer does not scan to the computer, you need to go through two categories of possible problems that may lead to no result. First, you should make sure that the printer (or, more precisely, the MFP) is properly connected and there are no communication problems between the computer and the scanning device. Then, step by step, you need to work with the operating system of the computer.

The instruction below is relevant for both a separate independent scanner and a complex device (MFP). With the latter, it often happens that the printer prints but does not scan.

Content

Quick resumption of scanning
Verification0004
Complete uninstall and reinstall
Disable Quiet Mode
Remove documents from the print queue
Check if the scanning component is working
Log in with a different account

Quick resume scan

If the scanner has stopped working Windows or software firmware of the device itself. It is always recommended to restart the computer and the scanner first to avoid unnecessary actions.

The first is restarted via the Start menu with the Restart option. The scanner or MFP is restarted by turning off and on again with the button on the case. After turning off the scanner, unplug the connection cable from the computer or laptop. Also unplug the scanner's network cable from the wall outlet. Let the device rest for 5 minutes.

Then reconnect the scanner to the computer and try to scan the document. If you succeeded in completing the scan, then you do not need to study the instructions further.

If the problem recurs intermittently, you should be concerned. It is likely that the printer is already experiencing a failure that needs to be fixed. To do this, it is better to take the device for diagnostics and repair and a certified service center. If you do not immediately take any action, then a complete failure of the equipment is possible.

Check connection

If the scanner does not work, you should immediately make sure that the connection is good.

Look at the vehicle panel. If the device is multifunctional, then there will be many indicators. As a rule, the on / off button of the equipment has a built-in indicator. In ready mode, the button should glow bright green.
If the button is off, press once to turn on the device. The absence of a result requires checking that the printer is connected to the mains at all. If the cord is plugged in, check that the outlet is working by connecting another device. When another device starts up, but the scanner does not turn on, the problem is hardware in nature. Perhaps the button has broken, the power supply or other hardware components, individual parts have failed. By the way, if the power supply is on the power cord, you can try using a different power cable. This will rule out or confirm the cause of the cable failure. When the other cord tested positive, the problem is in the technique.
Then check the next section of the connection chain - the USB cable from the printer to the computer or laptop. Make sure that the plug is firmly inserted into the USB port and the connector on the printer.

Let's assume that everything is OK with the connection. Then you need to make sure that the computer recognizes the printer and considers it connected.

Press Windows+R.
Type the command "control printers" and click "OK".
Find the model of office equipment in the list.

When fully operational, the icon should not be translucent. If there is an exclamation mark or other warning icons nearby, then there are problems.

But when the icon is not clear, it means that:

The USB cable is damaged and does not transfer data;
the affected connector on the laptop or system unit is damaged;
the connector on the PC does not work, is disabled by the system in the BIOS, or the driver for the controller is not installed;
Connection made via extension adapter. Too much cable length can lead to communication problems. As a result, printing or scanning will take a long time to start.

What to do:

If the icon in the device list does not become active, the printer is most likely the cause. Additionally, try restarting your computer again. But when the icon is activated, but the scanner still does not scan, the reason is a system violation.

The scanner, printer, or multifunction device may go into sleep mode when not used for a long time to conserve power. The ready indicator in sleep mode will also glow, but dimly. In this case, you need to transfer the device to the “Ready” status by pressing the power button once.

Problems with Wi-Fi connection

Much more problems when a Wi-Fi network is used to connect through a router.

Check if the access point is working. Connect with another device and try to access the Internet.
Reboot the router. Double-click the button on the back or bottom of the router.
Log in to the router's administration interface and check if the printer's access is blocked. It happens that the router is limited by the number of devices and cannot accept, for example, more than 5 incoming connections. If there are already 5 devices on the network (taken as an example), the scanner will not be able to enter the network. This means that the document will not be scanned from the computer.

The router should preferably be located in a neutral location. For example, in the corridor of an apartment, so that the signal arrives evenly throughout the room. If the router is weak, it will be located in the kitchen, and the scanner will be in a remote room, then the signal can be received at almost zero level.

It is also recommended to place the router away from powerful household appliances with electromagnetic radiation.

Typical problems for MFPs

If you have Canon equipment

Sometimes the scanner on a Canon printer does not work due to a conflict between the computer system and the Canon Toolbox proprietary program. The problem is relevant on Windows 10 after a series of regular updates.

To solve it, you need to install a special driver patch. Go to the official Canon website, select your device model from the list, then download the patch.

You can also disable a system component or uninstall a proprietary program. Let's say that you do not want to remove the software, then we will disable the service component.

Hold down the Windows button and press R.
Type the command "control" without quotes and press "Enter".
Go to the "Programs" section, then to the "Programs and Features" subsection.
On the left side of the window, click Turn Windows features on or off.
Scroll down the list of components to the very bottom and expand the Print and Document Services directory, inside uncheck Windows Fax and Scan. Save changes by clicking "OK". Restart Windows for the changes to take effect.
Try using a Canon scanner.

Software causes

All manipulations are performed only on the computer.

What else to do

The suggestions above will help in most cases.

But there are some more effective methods if it does not scan Windows 10 or in another version of "windows".

Run the troubleshooter

This is a standard tool in any Windows. You can launch a tool for diagnosing a specific printer right away through the context menu.

For Windows 10, you can follow the following step-by-step algorithm:

Through "Start", go to "Settings".
Open the Update & Security section.
On the left, select Troubleshoot.
On the right, click on what has problems and click on "Run ...".
If there is no choice right away, then follow the link "Additional funds ...".
And only then start the tool.

Once launched, the tool will begin discovery. If multiple printers are connected, select the one to be diagnosed. Please wait for the error scan to finish. At the end, it will write to you that no problems were found, or provide a list of violations with the opportunity to try to fix them.

Complete uninstall and reinstall

Many users have reported that completely uninstalling the printer from Windows often works. In this case, both the driver package and the printer are subject to removal. Then the device is re-added to the computer and firewood is installed.

Disable silent mode

Silent mode reduces the volume of sounds that are made when moving mechanisms. When turned on, the scanner may work poorly or not at all.

An example of disabling the mode for Canon devices:

Through the "Devices and Printers" window, go to "Printer Properties".
On the Maintenance tab, go to Silent Settings.
You can make individual settings for the activation of silence or make a complete shutdown.

Often there is a separate button on the case itself to deactivate the mode.

Remove documents from the print queue

If you want to print several files at once, then all documents are placed in the queue and processed as the previous files are processed. But sometimes the queue freezes, because of which printing is interrupted, the documents remain in the queue list until they are removed from there by yourself. Hanging jobs can affect scanning, so you need to clear the print queue.

Check the operation of the scanning component

Although the component should be enabled by default, sometimes it is in an inactive state. Therefore, scanning does not work even when there is no other violation.