its about the CT scan and generations in the form of PPT explaining each of first generation , second generation, third generation, fourth generation, fith generation and sith generation
it includes generations and advancement in CT. In generations fifth generation CT is described in detail.
UFC detector, stellar detectors and gemstone detector is also described
straton x-ray tube, MRC, LIMAX and aquillion one xray tube
different techniques used in CT
dual energy CT is also described
Basic physics of multidetector computed tomography ( CT Scan) - how ct scan works, different generations of ct, how image is generated and displayed and image artifacts related to CT Scan.
Computed Tomography and Spiral Computed Tomography JAMES JACKY
1. Computed Tomography / Spiral Computed Tomography
2. Clinical and Principle Operation of Computed Tomography
3. Law and Regulation in Malaysia
4. Radiation Dose
This slide best explains the introduction of CT, basis and types of CT image reconstructions with detailed explanation about Interpolation, convolution, Fourier slice theorem, Fourier transformation and brief explanation about the image domain i.e digital image processing.
it includes generations and advancement in CT. In generations fifth generation CT is described in detail.
UFC detector, stellar detectors and gemstone detector is also described
straton x-ray tube, MRC, LIMAX and aquillion one xray tube
different techniques used in CT
dual energy CT is also described
Basic physics of multidetector computed tomography ( CT Scan) - how ct scan works, different generations of ct, how image is generated and displayed and image artifacts related to CT Scan.
Computed Tomography and Spiral Computed Tomography JAMES JACKY
1. Computed Tomography / Spiral Computed Tomography
2. Clinical and Principle Operation of Computed Tomography
3. Law and Regulation in Malaysia
4. Radiation Dose
This slide best explains the introduction of CT, basis and types of CT image reconstructions with detailed explanation about Interpolation, convolution, Fourier slice theorem, Fourier transformation and brief explanation about the image domain i.e digital image processing.
Computed tomography (CT scan) is a medical imaging procedure that uses computer-processed X-rays to produce tomographic images or 'slices' of specific areas of the body. These cross-sectional images are used for diagnostic and therapeutic purposes in various medical disciplines.
generations of CT, explains each generations of CT, muti detector computer tomography, slip ring technology, main terminologies such as FOV , pitch, voxel and matrix, pixel size equation. EBCT, Basic configuration of CT, Data acquisition systems DAS, multi-slice CT
Computer tomography (CT), originally known as computed axial tomography (CAT or CT scan) and body section rentenography.
It is a medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.
The word "tomography" is derived from the Greek tomos (slice) and graphein (to write). CT produces a volume of data which can be manipulated, through a process known as windowing, in order to demonstrate various structures based on their ability to block the X-ray beam.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
2. Introduction of CT scan solves the major drawbacks
of conventional radiography Viz. superposition of
overlaying structures and scatter.
Both these reduces image contrast.
In the early1970s Godfrey Hounsfield developed a
scanner and demonstrated.
Cormack is a physicist who developed mathematics
for the reconstruction of image from multiple
projections.
The basic principle of computed tomography is
reconstruction of image from multiple projections.
In1979 Hounsfield and Cormack shared Noble prize
in medicine for this invention.
3. CT scanners are classified into different
categories
Based on source detector configuration and
their relative movement.
5. The original EMI scanner consists of an X-ray tube
and a pair of detectors.
Tube and detectors are mounted on a gantry
opposite to each other.
A reference detector is placed in the path of X-ray
beam before it reaches to the patient.
The source-detector system makes linear and
rotatory motions.
The linear motion was repeated over and over for
180 times.
Between each of these linear movements the gantry
rotated 10 .
6. The axis of rotation passes through the centre of the
patient head.
The X-ray tube was on during linear motion and off in
rotatory motion.
The transmitted X-rays was measured for 160 times
during the linear motion.
Total 28,800 projections are counted.
The total scan time was 5 min and reconstruction time
is 1 min.
For 10 slices the scan time is about 25 to 30 min.
7. First Generation CT Scanner
The original EMI scanner belongs to first generation
CT scanner.
In all other first generation CT scanners only one
detector per slice.
Detector used in this CT scanners was NaI(Tl).
Image quality is excellent in this type of CT
scanners.
9. Second Generation CT has Rotate-Translate
movement.
In this narrow fan beam and an array of detectors are
used. About 30 detectors are arranged along an arc.
Due to the increased utilization of X-ray output (about
30 times more than the first generation) scan time was
reduced.
Scan time per slice reduces to 10 to 90 sec.
Inclusion of scatter component is more in this
generation compared to first generation.
11. In third generation CT scanners, translational motion
is completely removed.
X-ray tube and detector system makes rotatory
motion around the patient for acquiring information,
hence it is called Rotate-Rotate movement.
In this, a wide fan beam is used to cover the entire
body and more no of detectors (more than 800) are
used.
In this system, scan time reduces to about 5 seconds.
Newer systems have scan time of about 1.5 sec.
A single detector towards the end of array acts as the
reference detector.
12. In third generation CT the major drawback is ring
artefact.
This is due to the failure of detector.
This problem is rectified in fourth generation CT
scanners by the use of stationary detector ring.
14. Rotate – Stationary movement.
In this system a detector ring is used around
the patient. X-ray tube is rotating inside the
detector ring.
Each detector acts as its own reference
detector.
Scan time is reduced to about 1 sec.
16. No moving parts.
In this a large arc of tungsten is used as X-ray target .
Detector ring is positioned directly opposite to the
tungsten arc.
An electron beam steered through a wave guide to
strike the tungsten arc through a bending magnet to
produce x-rays.
It is not very common type.
17. During the X-ray production patient couch is
moved to image different body cross-sections.
Capable of 50 m sec scan time.
It can produce fast-frame-rate CT moves of
beating heart.
It has special applications in cardiology
18. Slip ring technology
In previous generations, the rotation of source -
detector system around the patient was carried out
by the movement of the system through 3600 rotation
in one direction for a scan and in opposite direction
for the next scan.
Continuous rotation of source-detector system
became possible with the introduction of Slip-ring
technology.
Slip-ring technology is used in modern CT scanners
20. In spiral CT source and detector system makes
continuous motion around the patient, the couch too
moves continuously into the axial direction.
As a result x-ray beam follows a spiral/helical trajectory
hence the name is spiral/helical CT.
Speed of rotation of the gantry and speed of table
determines the pitch of the helix.
Pitch =couch movement per 3600 / Slice thickness.
During the spiral CT scan image data is received
continuously
21. However the data obtained during spiral scan may not be
sufficient for reconstruction of images of all slices along
the axial direction.
Therefore image reconstruction in spiral CT is done by
the interpolation of data available at 3600 apart.
Entire scan can be done in a breath hold time.
Axial resolution decreases with increase in pitch.Smaller
pitch increase patient dose.
Longer processing time as more data have to be
handled.
22. Spiral CT is advantageous in CT Fluoroscopy as use of
contrast media can be minimised .
Reconstruction of images is possible in different planes
3D image too can be reconstructed.
Applications of Spiral/helical CT
23. MULTI SLICE CT
The principle in multi slice CT is similar to the
helical / spiral CT but there are more number of
detector channels.
No. of channels : 4, 8, 16, 32, 40 & 64.
use of cone beam
The major advantage of multi slice CT is more
volume is covered in a single scan .
Effective utilization of x-ray beam.
24.
25. Generation Configuration Detectors Beam Min Scan Time
First Translate-rotate 1~2 Pencil thin 2.5 min
Second Translate-rotate 3~52 Narrow fan 10 sec
Third Rotate-rotate 256~1000 Wide fan 0.5 sec
Fourth Rotate-fixed 600~4800 Wide fan 1 sec
Fifth Electron beam 1284 detectors
Wide fan
beam
33 ms