Essay: Xrays, MRIs, Ultrasound

Task 1
1. (a)
X-rays are created in an x-ray tube. The tube comprises of a cathode side (negative electrical charge) and an anode side (positive electrical charge). An x-ray beam is created by passing an electron beam through a vacuum between a cathode (-) and an anode (+). The positively charged anode draws in the quickly moving, contrarily charged electrons.
In the x-ray tube, a surge of quick moving electrons is pulled in and guided from the cathode to the anode. As the electrons impact and collaborate with the atoms on the anode target on, an incredible measure of energy is delivered. 1% of this energy is as x-radiation. 99% shows up as warmth and must be expelled from the anode.
The tube walled in area is protected and a progression of lead shades permit the demonstrative beam to exit (booklet, 2016)
1 (b)
X-rays are a sort of radiation that can go through the body. They can’t be seen by the naked eye and you can’t feel them. As they go through the body, the vitality from X-rays is consumed at various rates by various parts of the body. An identifier on the opposite side of the body grabs the X-beams after they\’ve gone through and transforms them into a picture. Thick parts of your body that X-beams think that it’s harder to go through, for example, bone, appear as clear white zones on the picture. Milder parts that X-beams can go through more effectively, for example, your heart and lungs, appear as darker zones(imaging, 2016)
1b (i) A X-beam picture intensifier (XRII), commonly known as a C-Arm or Fluoroscope in restorative settings, is a profoundly complex bit of hardware which utilizes x-beams and delivers a \”live\” picture bolster which is shown on a TV screen. The term image intensifier alludes to an exceptional segment of the machine, which permits low force x-beams to be enhanced, bringing about a less dosage to the patient.
The general framework comprises of a x-beam source, input window, input phosphor, photo-cathode, vacuum and electron optics, yield phosphor and yield window. It permits to bring down x-ray measurements to be utilised on patients by amplifying the power created in the yield picture, empowering the viewer to effortlessly observe the structure of the object being imaged. (Contributions,2016)
An image intensifier or (XRII) is utilized as a part of two ways:
• As a settled bit of hardware in a committed screening room
• Mobile Equipment for use in theatre
Picture 1: shows a picture of an image intensifier (Contributions, 2016).
1.b (ii)
Contrast materials, likewise called contrast agents or contrast media, are utilized to enhance photos within the body delivered by x-rays, computed tomography (CT), magnetic resonance imaging (MRI), what’s more, ultrasound.
Frequently, contrast materials permit the radiologist to recognize ordinary from anomalous conditions. Contrast materials are not colours that forever stain inner organs. They are substances that incidentally change the way x-beams or other imaging apparatuses associate with the body. At the point when acquainted into the body earlier with an imaging exam, contrast materials make certain structures or tissues in the body seem distinctive on the pictures than they would if no contrast material had been directed.
Contrast materials recognize or “differentiate” chosen regions of the body from encompassing tissue. By enhancing the perceivability of organs, veins or tissues, contrast materials help doctors analyse therapeutic conditions.
Contrast materials enter the body in one of three ways, they can be:
• gulped (taken by mouth or orally)
• regulated by douche (given rectally)
• infused into a blood vessel (vein or artery; additionally, called given intravenously or intra-arterially) (Butterfly, 2016).
1.b (iii)
A barium swallow is a therapeutic imaging technique used to look at the upper GI (gastrointestinal) tract, which incorporates the throat, stomach, and small digestive system. The patient drinks a suspension of barium sulphate. X-rays are taken after the barium has been gulped.
The barium suspension seems white on the X-rays and uncovers the frameworks of the upper GI tract(GOV.UK,2016).
2 (a)
I = Ioe-µx
2.a (i) State what I0 represents in this equation
Io in the equation stands for = Initial intensity.
2.a.(ii) Bone has an attenuation coefficient of 3.3 cm-1. Calculate the thickness in cm of bone that will reduce the X-ray intensity by half.
Coefficient u = 3.3cm-1
Given, from the question [2I = I
According to the formula,
I = Ioe-µx
I = 2 I e -3.3x
I = 2 e-3.3x
½ = e-3.3x
½ = 1/e-3.3x
e 3.3x = 2
This can also be written as,
Loge 2 = 3.3x (from e y = x loge x = y)
= In 2 = 3.3x
= 0.69/3.3 = x
= x = 0.21 cm
2 (b)
The gut (gastrointestinal tract) does not appear extremely well on normal X-ray pictures. However, on the off chance that you drink a white fluid that contains a concoction called barium sulphate, the blueprint of the upper parts of the gut (throat, stomach, and small digestion systems) shows up plainly on X-beam pictures. This is because x–rays don’t go through barium.
Depending upon which portion of your gut is being taken a gander at, you may have at least one of the tests, for example, barium meal.
In every test, the barium coats the covering of the gut being tried.
(Butterfly,2016)
3. Modernized (or figured) tomography, and regularly once in the past alluded to as electronic hub tomography (CAT) scan, is an X-ray method that consolidates numerous X-ray pictures with the guide of a PC to create cross-sectional perspectives and, if necessary, three-dimensional pictures of the inside organs and structures of the body. Mechanized tomography is more usually known by its shortened names, CT output or CAT check. A CT output is utilized to characterize typical and strange structures in the body or potentially help with methods by serving to precisely direct the situation of instruments or medicines.
A substantial doughnut formed X-ray machine or scanner takes X-ray pictures at various edges around the body. A PC prepares these pictures to deliver cross-sectional photos of the body (Medicinenet.com,1996-2016)
Task 2
1. Describe the physical characteristics of sound waves.
Sound is a longitudinal, mechanical wave. Sound can go through any medium, however it can\’t go through a vacuum. There is no sound in space. All waves have certain attributes.
The three most basic ones for sound work are demonstrated as follows:
Figure 1: (GEHealtcare,2016)
Wavelength: The distance between any point on a wave and the equivalent point on the next phase. Literally, the length of the wave.
Figure2: (GEHealthcare,2016)
Amplitude: The quality or force of a wave flag. The “tallness” of a wave when seen as a diagram. Higher amplitudes are translated as a higher volume, subsequently the name “intensifier” for a gadget that expands amplitude.
Figure3: (GEHealthcare,2016)
Frequency: The quantity of times the wavelength happens in one moment. Measured in kilohertz (Khz), or cycles every second. The quicker the sound source vibrates, the higher the frequency
Higher frequencies are deciphered as a higher pitch. For instance, when you sing in a sharp voice. (Mediacollege.com, 2016)
2 (a)
The Piezoelectric Effect
Piezoelectric Effect is the capacity of specific materials to create an electric charge because of connected mechanical stress. The word Piezoelectric is gotten from the Greek piezein, which intends to crush or press, and piezo, which is Greek for \”push\”. One of the one of a kind attributes of the piezoelectric impact is that it is re-eversible, implying that materials showing the direct piezoelectric impact (the generation of power when stress is connected) likewise display the opposite piezoelectric impact (the era of stress when an electric field is connected (Johnson, 2016).
2 (b)
An ultrasound scan, now and again called a sonogram, is a technique that utilizations high-frequency sound waves to make a picture of part of within the body. An ultrasound scan can be utilized to screen an unborn infant, analyse a condition, or guide a specialist amid specific systems.
You can’t hear these sounds they skip off various parts of the body, they make “echoes” that are picked waves, yet when up by the test and transformed into a moving picture. This picture is shown on a screen while the scan is completed.
• internal ultrasound scan – the probe is embedded into the body
Inward or transvaginal ultrasound scan
An inward examination permits a specialist to look more carefully inside the body at organs, for example, the prostate organ, ovaries or womb. A “transvaginal” ultrasound signifies ‘through the vagina’
Internal Ultrasound scan (GOV.UK, 2016)
while the procedure is taking place, you’ll be asked to either lie on your back, or sideways with your knees drawn up towards your mid-section. A little ultrasound probe with a sterile cover, very little not more extensive than a finger, is then tenderly taken into the vagina or rectum, and pictures are transmitted to a screen(GOV,2016).
Endoscopic ultrasound check/scan
During an endoscopic ultrasound scan, an endoscope is embedded into your body, for the most part through your mouth, to look at regions, for example, your stomach or neck (oesophagus).
Picture 1: showing endoscopic ultrasound (GOV.UK, 2016)
You’ll as a rule be requested to lie on your side as the endoscope is painstakingly pushed down towards your stomach.
The endoscope has a light and an ultrasound gadget on the end. When it has been embedded into the body, sound waves are utilized to make pictures in the same way as an outside ultrasound (GOV.UK, 2016).
And below are also differences A scan and B scan:
A-scans
nates an ultrasonic beat and the time taken for the beat to ricochet off an object and return is graphed with a specific end goal to decide how far away the object is. A- scans just give one-dimensional data and in this way, are not valuable for imaging (Simmons, 2016).
B-Scans
B-scans can be utilized to take a picture of a cross-segment through the body. The transducer is cleared over the zone and the time taken for pulses to return is utilized to decide distances, which are plotted as a progression of dabs on the picture. B-Scans will give two-dimensional data about the cross-segment (Simmons, 2012).
2 (c)
Impedance matching is utilized so ultrasound may pass effortlessly over a limit without extensive reflection. An impedance matching gel has a comparable acoustic impedance as skin. This permits ultrasound to go through the gel-skin limit without vast reflection, whereas an air-skin limit would bring about a huge reflection
The acoustic impedance (Z) of air is 400 kg m-2 s-1 and that of human skin is 1.7 x 106 kg m-2 s-1, so if an ultrasound transducer were to be put specifically on to the patient’s skin, Ir/I0 ≈ 0.999. In this way 99.9% of the episode ultrasound force would be reflected and just 0.1% would really be transmitted into the body utilizing ultrasound, little can be seen past the lungs or some other gas-filled cavities(Simmons,2016).
2 (d) Suggest why it is desirable to have an ultrasound of short wavelength for a scan.
Ultrasound utilizes high frequency sounds that are higher than the human ear can listen. ie. 20 000 Hz. Ultrasound can\’t recognize objects that are smaller than its wave-length and in this manner higher frequencies of ultrasound deliver better resolution. Then again, higher frequencies of ultrasound have short wavelengths and are retained effortlessly and in this way are not as infiltrating. Therefore, high frequencies are utilized for checking regions of the body near the surface and low frequencies are utilized for territories that are more profound down in the body. These frequencies gene partner extend between 1-50 MHz (Simmons, 2016)
Picture 1: Diagram showing how ultrasound is produced and detected (Image credit: Jacaranda Physics 1 2nd Edition © John Wiley & Sons, Inc
3(a)
A Doppler ultrasound is a non-invasive test that can be utilized to appraise your blood course through veins by skipping high-frequency sound waves (ultrasound) off circulating red blood cells. A regular ultrasound utilizes sound waves to create pictures, yet can\’t demonstrate blood stream.
A Doppler ultrasound may analyse many conditions, including:
• Blood clumps
• Poorly working valves in your leg veins, which can make blood or other fluids pool in your legs (venous inadequacy)
• Heart valve surrenders and inborn coronary illness
• A blocked supply route (blood vessel impediment)
• Decreased blood flow into your legs (fringe supply route sickness)
(Foundation, 1996-2016).
3.b.(i) Here,
v = velocity = 1.5 x 1000 = 1570 m s-1
Z = Acoustic impedance = 1.66 x 10 kg m-2 s-1
[ p = z ]
v
Density = 1.66 x 106
1570
Density = 1060 (kgm-3 )
3.b. (ii) The wavelength of ultrasound in the blood.
Wavelength (λ) = v (speed)
f (frequency)
Wavelength (λ) = 1570
2.4 x 106
Wavelength (λ) = 6.5 x 10-4
3. (c)
Transducer Probe
In a typical ultrasound, millions of pulses and echoes are sent and received each second. The probe can be moved along the surface of the body and angled to obtain various views.
1.The ultrasound machine transmits high-recurrence (1 to 5 megahertz) sound heartbeats into your body utilizing a probe.
2.The sound waves go into your body and hit a limit between tissues (e.g. be-tween liquid and delicate tissue, delicate tissue, and bone).
3.Some of the sound waves get reflected to the probe, while some go on further until they achieve another limit and get reflected.
4.The reflected waves are gotten by the probe and transferred to the machine.
5.The machine computes the separation from the probe to the tissue or organ (limits) utilizing the speed of sound in tissue (5,005 ft/s or1,540 m/s) and the season of the every reverberates arrival (normally on the request of millionths of a moment).
6.The machine shows the separations and forces of the echoes on the screen, shaping a two-dimensional picture like the one demonstrated as below.
Photo courtesy Karim and Nancy Nice
Picture 1: showing Ultrasound image of a growing foetus (approximately 12 weeks old) inside a mother\’s uterus. This is a side view of the baby, showing (right to left) the head, neck, torso, and legs (Healthcare, 2016)
.
Picture 1: Showing different shapes and sizes of transducers (Healthcare, 2016)
4) Ir = intensity of reflected echo.
Li = intensity of incident beam at the boundary.
Z1 = acoustic impedance of air = 4.29 x 102
Z2 = acoustic impedance of skin = 1.65 x 106
Therefore, Ir = (Z2 – Z1) 2
li = (Z2 + Z1)2
= (1.65 x 106 – 4.29 x102) 2
(1.65 x 106 + 4.29 x 102) 2
= 1650000 – 429
1650000 + 429
= (1649571
1650429
Since, 99.8% was reflected, the percentage transmitted into the skin = 100 – 99,8 =0.2%
Task 3
1.
MRI Components
and how they Function to obtain diagnostic information
about internal organs
Picture 1: Above is a diagram showing a person in the MRI scanner (Kibria, 2016)
Magnet
The magnet is the most imperative and greatest part of the MRI gadget. It is this
magnet that permits the MRI machine to deliver amazing pictures. There is a
flat tube that goes through the magnet and is known as a drag. The magnet
is to a great degree and its capability and quality is measured in either ‟teslaˮ or‟ gaussˮ (1 tesla = 10 000 gauss). Most MRI magnets utilize a magnetic field of 0.5 to 2.0 tesla, when the Earth\’s magnetic field is just 0.5 gauss. The magnetic field is created by getting current through various coils that are inside the magnet, bringing about a condition of superconductivity, which delivers a ton of vitality by decreasing the resistance in the wires to zero.
Gradient Coils
There are three distinctive gradient coils that are inside the MRI machine and are situated inside the primary magnet. Every one of these create three diverse magnetic fields that are each less in strength than the primary field. The gradient coils make a variable field (x, y, z) that can be expanded or diminished to permit and diverse parts of the body to be checked/scanned by changing and modifying the fundamental magnetic field.
Picture 2: Above is a diagram showing how the coil inside an MRI work (Kibria, 2016)
Radio Frequency (RF) coils
The essential capacity of the RF coils is to transmit radio frequency waves into the patient\’s body. There are various coils situated inside the MRI scanner to transmit waves into various body parts. If a specific zone of the body is determined, then all the RF coils normally turned out to be focused on the body part being imaged to take into consideration a superior scan.
Picture 3: Diagram of Radio frequency coils (Kibria, 2016)
Patient Table
This part basically slides the patient into the MRI machine. The position at which the patient rests on the table is dictated by the part of the body that is being examined. Once the part of the body under examination is in the correct focal point of the magnetic field, which is alluded to as the isocentre, the examining procedure begins.
Antenna/Computer System
The antenna is an exceptionally touchy gadget that effectively recognizes the RF signals radiated by a patient\’s body while experiencing examination and encourages this data into the PC framework. The PC framework is an effective framework, whose major capacity is to get, record, and break down the pictures of the patient\’s body that have been filtered. It deciphers the information sent in by the reception apparatus and after that, produces a reasonable picture of the body part being analysed (Kibria,2016).
The Powerful MRI Computer System (Kibria,2016)
2. Describe how MRI can be used to determine the result of a brain tumours and as a post mortem tool.
MRI scans not only provide higher-definition images, but they can also show sagittal and coronal sections of the brain.
Picture 1: Diagram showing brain scans (Healthcare, 2016)
1.The scanner\’s magnetic field adjusts the far weaker magnetic fields of all the protons in all the hydrogen molecules in the water contained in the body\’s tissues.
2.The scanner then uses radio waves to shell the part of the cerebrum that is to be imaged.
3. After the radio waves are switched off, the protons come back to their unique adjustment. All the while, they emanate a frail radio signal, known as their magnetic resonance. The force of this magnetic resonance is relative to the thickness of the protons in the different tissues, and thus to the rate of water that they contain.
4. Special sensors recognize the fluctuating powers of this reverberation and hand-off this data to a PC.
5. The PC forms this data to make pictures of tissue areas along different axes.
Picture 1: showing an MRI for a brain scan ( Healthcare, 2016)
Task 4
1.
computed tomography (CT scans)
Utilizes different X-rays to deliver cross-sectional layers that show very precise pictures inside the body, including bones, organs, tissues, and tumours
Advantages: (Medicinewise, 2016)
• Quick and effortless
• Can analyse and manage treatment for a more extensive scope of conditions than normal X-ray
• Can identify or reject the existence of more difficult issues
• Can be utilized to check if a previously treated ailment has re-appeared (Medicinewise, 2016).
Magnetic resonance imaging (MRI)
Utilizes magnetic fields and radio waves to demonstrate definite pictures of organs, delicate tissues, bones, tendons, and ligament
Advantages:
• Typically, non-intrusive and easy
• Utilizes no ionizing radiation
• Can analyze and control treatment for an extensive variety of conditions
• Can give comparable data to CT in a few sorts of examinations (Medicinewise, 2016)
Courtesy of GE Healthcare (Healthcare, 2016)
pictures of areas inside the body.
Ultrasound
Utilizes high-recurrence sound waves to deliver moving pictures onto a screen of within the body, including organs, delicate tissues, bones, and an unborn child
Advantages:
• Generally non-obtrusive, safe, and moderately effortless
• Utilizes no ionizing radiation
• Does not normally require infusion of a contrast medium (colour)
• Can analyse a scope of conditions in various parts of the body, for example, the stomach area, pelvis, veins, breast, kidneys, muscles, bones, and joints.
• Can be utilized to keep an eye on the wellbeing of a child during pregnancy (Medicinewise, 2016)
Plain X-ray
X-ray Utilizes X-rays to show pictures of bones, a few tumours and other thick matter.
Advantages:
• Brisk, non-intrusive and effortless
• Can analyse different ailments and wounds, including broken bones, a few malignancies, and diseases (Medicinewise,2016)
–
Task 4
2.
Ultrasound may be more suitable and preferred when it comes to scanning of an unborn baby due to the two main reasons stated below:
Compared to x-ray photographs, ultrasound scans:
• Ultrasound is (non- Ionising) so, no harm or damage is caused to unborn baby and living cells. Also,
• Ultrasound produce images of soft tissue and very clear pictures(Careyoupuppy,2016).