MRI and CT Scan the differences

Summary

This video script discusses various medical imaging techniques, focusing on CT scans, MRI scans, and PET scans. CT scans use X-rays and a computer to create 3D images, while MRI scans employ magnetism for similar purposes. Both may use contrast mediums for enhanced imaging. PET scans, involving radioactive substances, are particularly useful in cancer diagnosis, often combined with CT scans for better visualization. The script addresses patient comfort, such as dealing with claustrophobia and noise during MRI scans, and the importance of removing metallic objects before scans. It highlights how these scans complement each other in providing detailed information for cancer diagnosis and treatment.

Takeaways

• 🔍 **CT Scan**: A computerized tomography (CT) scan uses multiple X-rays and a computer to create a 3D image of the body's interior.
• 🛌 **CT Scanner Design**: The CT scanner features a moving couch that glides through a large hoop-shaped device, minimizing claustrophobia.
• 💉 **Contrast Medium**: A small needle is used to inject a contrast medium into the arm before the scan to enhance image clarity.
• 🔁 **Two Scans**: Patients undergo two scans, one for a general view and another for detailed imaging, each lasting about 20 seconds.
• 🧲 **MRI Scan**: An MRI scan uses magnetism to build a 3D image, and some patients may experience claustrophobia due to the narrow cylinder.
• 🚫 **Metallic Objects**: Before an MRI, patients must remove all metallic objects and inform the radiologist of any internal metal objects like pacemakers or surgical clips.
• 🎵 **Noise and Comfort**: MRI scans can be noisy, so headphones playing music are offered to patients to reduce noise and promote relaxation.
• ⏳ **Scan Duration**: An MRI scan lasts between 30 minutes to an hour, depending on the area being scanned.
• 💊 **PET Scan**: PET (positron emission tomography) scans involve injecting a radioactive substance, often a form of glucose, to help identify cancerous tissues.
• 🔗 **Combined Scans**: PET scans are often used with CT scans to provide a more detailed and accurate image, especially in cancer diagnosis.
• 🔎 **Diagnostic Utility**: Ultrasound, CT, PET, and MRI scans each offer unique information and are often used in combination to diagnose and assess cancers effectively.

Q & A

What does CT stand for in medical imaging?

CT stands for Computerized Tomography, a device that takes multiple X-rays from different angles and uses a computer to create a three-dimensional image of the inside of the body.

How does the CT scanner work?

The CT scanner consists of a moving couch that slowly moves a person through a hoop-shaped device. It takes a series of X-rays to create a detailed, cross-sectional image of the body.

What is the purpose of the contrast medium used in CT scans?

The contrast medium is a liquid injected into the body to enhance the definition of the scan, making it easier to distinguish between different types of tissues and organs.

Why do patients have to hold their breath during a CT scan?

Patients are asked to hold their breath during the scan to prevent any movement that could blur the images and ensure the accuracy of the scan.

What is an MRI scan and how does it differ from a CT scan?

An MRI scan uses magnetism to build up a three-dimensional image of the inside of the body. Unlike CT scans, which use X-rays, MRI scans do not involve ionizing radiation.

Why might some people feel claustrophobic during an MRI scan?

The MRI scanner consists of a moving couch that moves a person through a cylinder that can be quite narrow, which might cause a feeling of claustrophobia in some individuals.

How can patients who suffer from claustrophobia be accommodated during an MRI scan?

For patients with claustrophobia, open MRI scanners are available, which reduce the tunnel effect and provide a more open feeling during the scan.

What is the PET scan and how does it work?

A PET scan, or Positron Emission Tomography, involves injecting a rapidly acting radioactive substance into the body. The scanner detects the radiation emitted by the substance, which can help identify areas of the body that are metabolically active, such as cancer cells.

Why is the radioactive substance used in PET scans important?

The radioactive substance used in PET scans is important because it can highlight areas of the body that are metabolically active, which can be particularly useful in identifying cancerous cells or determining the effectiveness of cancer treatments.

How long does a PET scan typically take?

A PET scan can take around an hour, including the time for the radioactive substance to be taken up by the tissues and the actual scanning time.

What is the role of ultrasound scans in cancer diagnosis and assessment?

Ultrasound scans use sound waves to create images of the body's internal structures. They are often used to assess the size and shape of tumors, guide biopsies, and monitor treatment responses.

Outlines

00:00

🏥 Medical Imaging Techniques

This paragraph introduces various medical imaging techniques, focusing on CT (Computed Tomography) scans and MRI (Magnetic Resonance Imaging) scans. CT scans use multiple X-rays from different angles to create a 3D image of the body's interior. The process involves a moving couch that passes the patient through a large hoop-shaped scanner. Patients may experience an injection of a contrast medium to enhance the scan's clarity. The scan is performed twice, once for a general overview and once for detailed imaging. MRI scans, on the other hand, use magnetism to create 3D images. These scans can be claustrophobic for some due to the narrow cylindrical design of the scanner. Open MRI options are available for those who suffer from claustrophobia. An injection of contrast medium is also used in MRI scans. The paragraph also touches on the use of headphones with music to reduce the noise from the scanner. Lastly, PET (Positron Emission Tomography) scans are mentioned as a newer innovation, which involves the injection of a radioactive substance, often a form of glucose, to help identify cancerous tissues. PET scans are usually combined with CT scans for better imaging results.

05:01

🔎 Choosing the Right Scan for Cancer Diagnosis

The second paragraph discusses the decision-making process for selecting the appropriate imaging scan based on the type of cancer being investigated. It emphasizes that the choice of scan depends on the suspected cancer type, and that different scans provide different types of information. For instance, some cancers may be better visualized with CT scans, while others might require MRI scans. PET scans can offer additional insights, especially in distinguishing between cancerous and non-cancerous tissues. The paragraph suggests that in some cases, a combination of scans or all three types might be necessary to gather comprehensive diagnostic information.

Keywords

💡CT Scan

A CT (Computed Tomography) scan is a diagnostic imaging procedure that uses X-rays and computer technology to create detailed cross-sectional images of the body. In the video, it is described as a device that takes multiple X-rays from different angles and uses a computer to generate a 3D image of the body's interior. The CT scanner consists of a moving couch that moves the patient through a hoop-shaped device. The process involves two scans: a general picture and a detailed scan, with the actual scanning lasting about 20 seconds.

💡Contrast Medium

Contrast medium is a liquid used in medical imaging to enhance the visibility of internal structures. It is injected into the body before a scan to improve the definition and clarity of the images. In the context of the video, a small needle is inserted into the patient's arm for the injection of this medium, which helps in obtaining a clearer and more detailed scan.

💡MRI Scan

An MRI (Magnetic Resonance Imaging) scan is a non-invasive diagnostic procedure that uses a magnetic field and radio waves to produce detailed images of the body's internal structures. The video explains that an MRI scanner also uses a moving couch that moves the patient through a cylinder, which can be narrow and cause claustrophobia in some individuals. Open MRI scanners are available for those who suffer from claustrophobia.

💡Claustrophobia

Claustrophobia is an anxiety disorder characterized by a fear of enclosed or confined spaces. In the video, it is mentioned as a potential concern for patients undergoing MRI scans due to the narrow design of the scanner. The script also mentions that open MRI scanners are available to reduce this issue for patients who experience claustrophobia.

💡Metallic Objects

Metallic objects can interfere with the magnetic fields used in MRI scans, leading to inaccurate imaging or even safety hazards. The video script emphasizes the importance of removing all metallic objects before undergoing an MRI scan and informing the radiologist if there are any internal metal objects, such as pacemakers or surgical clips.

💡PET Scan

A PET (Positron Emission Tomography) scan is a nuclear medicine imaging technique that produces 3D images of functional processes within the body. The video describes it as a scan that involves injecting a rapidly acting radioactive substance, commonly a radioactive form of glucose, to help identify active cancer cells. The PET scan is often used in conjunction with a CT scan to provide a more comprehensive image.

💡Radioactive Substance

A radioactive substance is a material that emits radiation and is used in medical imaging to visualize biological processes. In the context of the video, a small needle is used to inject a radioactive substance into the patient's arm before a PET scan. This substance is taken up by the tissues and helps to identify areas of the body that are metabolically active, such as cancer cells.

💡Ultrasound Scan

An ultrasound scan is a non-invasive medical imaging technique that uses high-frequency sound waves to create images of the body's internal structures. Although not described in detail in the video, it is mentioned as a complementary diagnostic tool to CT scans, PET scans, and MRI scans in assessing cancers.

💡Cancer

Cancer refers to a group of diseases characterized by the uncontrolled growth and spread of abnormal cells. The video discusses how different imaging scans, such as CT, MRI, and PET scans, are used to diagnose and assess cancers by providing detailed images of the body's interior and identifying metabolically active areas that may indicate the presence of cancer.

💡Lymph Glands

Lymph glands, also known as lymph nodes, are small, bean-shaped structures that produce and store cells that fight infection and disease. The video script mentions that cancer may cause lymph glands to enlarge, and PET scans can help determine whether the enlargement is due to cancer or another reason.

💡Scar Tissue

Scar tissue is the result of the body's healing process after an injury or surgery. In the context of the video, it is mentioned in relation to cancer treatment, where a PET scan can help differentiate between active cancer and scar tissue that remains after treatment.

Highlights

CT scan uses computerized tomography to create 3D images from multiple X-rays.

CT scanner features a moving couch and a hoop-shaped device to capture internal body images.

Most people do not experience claustrophobia in the CT scanner.

A contrast medium is injected to enhance the definition of the scan.

The scanning process occurs twice for general and detailed views, lasting about 20 seconds each.

Patients are asked to hold their breath during the brief scanning period.

MRI scan uses magnetism to build 3D images, contrasting with CT's X-ray approach.

Some people may feel claustrophobic in the more narrow MRI scanner.

Open MRI scanners are available for patients with claustrophobia.

Metallic objects must be removed before an MRI scan due to its magnetic nature.

Patients with internal metal objects like pacemakers must inform the radiologist before an MRI.

An injection of contrast medium is also used in MRI scans.

MRI scans can be noisy, but headphones with music are provided to reduce the noise.

MRI scans last for 30 minutes to an hour.

PET scan stands for positron emission tomography and uses radioactive substances for imaging.

PET scans are often used in conjunction with CT scans for better diagnostic accuracy.

PET scans can help determine if a shadow on a CT scan is cancerous or not.

PET scans are also useful post-cancer treatment to assess the nature of remaining lumps.

The PET scanner is narrower than a CT scanner but wider than an MRI scanner, causing less claustrophobia.

A radioactive substance is injected about an hour before a PET scan to be taken up by tissues.

In cancer diagnosis, ultrasound, CT, PET, and MRI scans often provide complementary information.

The choice of scan depends on the type of cancer suspected, and combinations of scans may be used.

Transcripts

another frequently used scan is a CT

scan CT stands for computerized

tomography a device which takes many

x-rays from different angles and uses a

computer to create a three-dimensional

picture of the inside of the body the CT

scanner consists of a moving couch not

particularly narrow that slowly moves a

person through a hoop that has the shape

of a very large dut the vast majority of

people will not experience any sense of

claustrophobia you'll be helped onto the

scanner couch by the radiographer these

days most people go into the scanner

feet first before the scan starts a

small needle will usually be inserted

into your arm for the injection of a

contrast medium this is a liquid that

enhances the definition of the scan

you'll go through the scanner twice the

first time is to get a general picture

of the whole body and the second is to

obtain the detailed scan the actual

scanning only lasts about 20 seconds

during which time you'll be asked to

hold your breath a more recent

Innovation is the MRI scan an MRI scan

uses magnetism to build up a

three-dimensional image of the inside of

the body like the CT scanner the MRI

scanner also consists of a moving couch

this slowly moves a person through a

cylinder that can be quite narrow and

some people find that this gives them a

feeling of claustrophobia there are a

few Open MRI scanners available for

patients who suffer from claustrophobia

which reduce this tunnel effect you'll

usually go into the scanner feet first

the radiographer will give you a button

on the end of a wire so if you have any

concerns you can immediately alert the

staff you can also talk to the nurses or

radiographers while you're in the

scanner as the scan uses magnetism

you'll need to make sure you've removed

all metallic objects you'll also need to

tell the radiologist if you have any

internal metal objects such as a

pacemaker or if you have any surgical

Clips before the scan starts a small

needle is inserted into your arm for the

injection of the contrast medium while

the scan is taking place it can be noisy

as the scanner produces a repeated

knocking sound you'll be offered

headphones through which music will be

played it's okay you can choose the

music you prefer to help reduce the

noise and to relax you the scan lasts

for 30 minutes to an hour the latest

development in scans is the Pet Scan pet

stands for positron emission

tomography in this scan you're given an

injection of a rapidly acting

radioactive substance which disappears

from the body in a few hours the

commonest substance that is used is a

radioactive form of glucose a pet scan

is not as good as a CT or MRI scan

scanning giving a good three-dimensional

picture of the body and is therefore

usually used together with a lowd do CT

scan to help produce a better

picture sometimes a pet scan may be

combined with a full CT scan the

advantage of a pet scan is that the

radioactivity helps to tell what is

inside a shadow shown on a CT scan in

particular whether it is cancerous or

not for example a cancer may have

enlarged lymph glands near to it and it

may be uncertain as to whether they are

enlarged because of cancer or for

another reason the pet will often help

sort out this dilemma pet scans can also

be helpful after treatment for a cancer

to sort out whether a remaining lump is

active cancer or is just dead or scar

issue the pet scanner also consists of a

moving couch that slowly moves a person

through a short tunnel this is a bit

narrower than a CT scan but much wider

than a an MRI scan and most people don't

find that it causes

claustrophobia about an hour before the

scan starts a small needle is inserted

into your arm for the injection of the

radioactive

substance the time is necessary for the

radioactive substance to be taken up by

the tissues unlike the CT and MRI scans

you usually go into the scanner head

first you go into the scanner twice the

first time is to get the CT scan and the

second time to get the Pet Scan the CT

scan takes just a few seconds but the

Pet Scan takes around an hour in

diagnosing and assessing cancers

ultrasound scans CT scans pet scans and

MRI scans are often complimentary and

may give different information for

example for some cancers CT scans will

give more accurate information whilst

for others an MRI scan is better for

others a pet C scan gives the best

information so the choice of which sort

of scan is used depends on which type of

cancer is suspected or being

investigated often a combination of some

or occasionally all of these scans may

be used in an individual