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.
brief but informative knowledge about how CT works and what are its components ... easy to understand as well as presenting during lectures and in classes . share it
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.
brief but informative knowledge about how CT works and what are its components ... easy to understand as well as presenting during lectures and in classes . share it
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
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
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.
Wind Turbines and their Potential for Cost ReductionsJeffrey Funk
These slides show how that long-term reductions in the cost of electricity from wind turbines have primarily come more from increasing the scale (rotor diameter and tower height) of wind turbines. See my other slides for details on concepts, methodology, and other new industries..
Digital image processing in recent year has shown a tremendous potential for application to medical sciences and one of them is “Computed Tomography scanning machine“. Conventional x-ray has a disadvantage while examining the internal structure of the body that it superimposes the 3D image of our body into single plane which makes diagnosis often difficult and confusing. But Computed tomography (CT) imaging systems generate three-dimensional (3-D) images of internal body structures using complex x-ray and computer-aided tomographic imaging techniques. Digital processing geometry are widely used in three-dimensional (3-D) reconstruction of bone geometry and density features for 3-D modelling purposes. For this C.t scanning is widely used in industrial sector and in medical sector. This report represents an overview of “C.T scanning” technique, its advantages and application related to different sector.
A detailed description of ct coronary angiography and calcium scoring with various aspects regarding the preparation, procedure, limitations and a short review regarding post CABG imaging.
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.
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
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
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micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
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MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
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2 Case Reports of Gastric Ultrasound
2. Definition / facts about CTDefinition / facts about 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.
3. HistoryHistory
The first commercially viable CT scanner was invented
by Godfrey Newbold Hounsfield in Hayes, England at
Thorn EMI Central Research Laboratories using X-rays.
Hounsfield conceived his idea in 1967, and it was
publicly announced in 1972.
It is claimed that the CT scanner was "the greatest
legacy" of the Beatles; the massive profits from their
record sales enabled EMI to fund scientific research.
Allan McLeod Cormack of Tufts University,
Massachussetts, USA independently invented a similar
process and they shared a Nobel Prize in medicine in
1979.
5. The original 1971 prototype took 160 parallel readings through
180 angles, each 1° apart, with each scan taking a little over five
minutes. The images from these scans took 2.5 hours to be
processed by algebraic reconstruction techniques on a large
computer.
The first production X-ray CT machine (called the EMI-Scanner)
was limited to making tomographic sections of the brain, but
acquired the image data in about 4 minutes (scanning two adjacent
slices) and the computation time (using a Data General Nova
minicomputer) was about 7 minutes per picture.
This scanner required the use of a water-filled Perspex tank with a
pre-shaped rubber "head-cap" at the front, which enclosed the
patient's head. The water-tank was used to reduce the dynamic
range of the radiation reaching the detectors (between scanning
outside the head compared with scanning through the bone of the
skull).
7. TomosynthesisTomosynthesis
Simple motion of a tube and Detector was used
before CT to create images at a given depth.
All anatomy not at the target level was blurred.
This gave a somewhat crude image and was
quickly replaced by CT.
With the advent of digital detectors and the
ability to post process this imaging method is
making a comeback.
8. GenerationsGenerations
generation configuration detector beam Min scan time
first Translate -rotate 1-2 Pencil thin 2.5min
second Translate -rotate 3-52 Narrow fan 10sec
Third Rotate- rotate 256-1000 Wide fan 0.5sec
fourth Rotate- fixed 600-4800 Wide fan 1sec
fifth Electron beam 1284 Wide fan
electron beam
33ns
9. 11stst
&2&2ndnd
generationgeneration
In the first and second generation designs, the X-ray
beam was not wide enough to cover the entire width of
the 'slice' of interest.
A mechanical arrangement was required to move the
X-ray source and detector horizontally across the field
of view.
After a sweep, the source/detector assembly would be
rotated a few degrees, and another sweep performed.
This process would be repeated until 360 degrees (or
180 degrees) had been covered. The complex motion
placed a limit on the minimum scan time at
approximately 20 seconds per image.
10. 33rdrd
&4&4thth
generationgeneration
In the 3rd and 4th generation designs, the
X-ray beam is able to cover the entire
field of view of the scanner.
This avoids the need for any horizontal
motion; an entire 'line' can be captured in
an instant.
This allowed simplification of the motion
to rotation of the X-ray source.
11. Third and fourth generation designs differ
in the arrangement of the detectors.
In 3rd generation, the detector array is as
wide as the beam, and must therefore
rotate as the source rotates.
In 4th generation, an entire ring of
stationary detectors are used.
12. Electron Beam CTElectron Beam CT
Electron beam tomography (EBCT) was
introduced in the early 1980s, by medical
physicist Andrew Castagnini.
It is a method of improving the temporal
resolution of CT scanners.
Because the X-ray source has to rotate by
over 180 degrees in order to capture an image
the technique is inherently unable to capture
dynamic events or movements that are quicker
than the rotation time.
13. Instead of rotating a conventional X-ray tube around the
patient, the EBCT machine houses a huge vacuum tube
in which an electron beam is electro-magnetically
steered towards an array of tungsten X-ray anodes
arranged circularly around the patient.
Each anode is hit in turn by the electron beam and emits
X-rays that are collimated and detected as in
conventional CT.
The lack of moving parts allows very quick scanning,
with single slice making the technique ideal for
capturing images of the heart.
EBCT has found particular use for assessment of
coronary artery calcium, a means of predicting risk of
coronary artery disease.
14. Helical or Spiral CTHelical or Spiral CT
Helical, also called spiral, CT was introduced in
the early 1990s, with much of the development
led by Willi Kalender and Kazuhiro Katada.
In older CT scanners, the X-ray source would
move in a circular fashion to acquire a single
'slice', once the slice had been completed, the
scanner table would move to position the
patient for the next slice; meanwhile the X-ray
source/detectors would reverse direction to
avoid tangling their cables.
15. In helical CT the X-ray source are attached to a freely
rotating gantry.
During a scan, the table moves the patient smoothly
through the scanner; the name derives from the helical
path traced out by the X-ray beam.
It was the development of two technologies that made
helical CT practical: slip rings to transfer power and
data on and off the rotating gantry, and the switched
mode power supply powerful enough to supply the X-
ray tube, but small enough to be installed on the gantry.
16. Multislice CTMultislice CT
Multislice CT scanners are similar in concept to the helical or
spiral CT but there are more than one detector ring.
It began with two rings in mid nineties, with a 2 solid state ring
model designed and built by Elscint (Haifa) called CT TWIN, with
one second rotation.
Later, it was presented 4, 8, 16, 32, 40 and 64 detector rings, with
increasing rotation speeds. Current models (2007) have up to 3
rotations per second, and isotropic resolution of 0.35mm voxels
with z-axis scan speed of up to 18 cm/s.
This resolution exceeds that of High Resolution CT techniques
with single-slice scanners, yet it is practical to scan adjacent, or
overlapping, slices - however, image noise and radiation exposure
significantly limit the use of such resolutions.
17. The major benefit of multi-slice CT is the
increased speed of volume coverage. This
allows large volumes to be scanned at the
optimal time .
The ability of multi-slice scanners to achieve
isotropic resolution even on routine studies
means that maximum image quality is not
restricted to images in the axial plane - and
studies can be freely viewed in any desired
plane.
18. Dual Source CTDual Source CT
Siemens introduced a CT model with dual X-ray tube
and dual array of 64 slice detectors, at the 2005
Radiological Society of North America (RSNA) medical
meeting.
Dual sources increase the temporal resolution by
reducing the rotation angle required to acquire a
complete image, thus permitting cardiac studies without
the use of heart rate lowering medication, as well as
permitting imaging of the heart in systole.
The use of two x-ray units makes possible the use of
dual energy imaging.
19. Diagnostic useDiagnostic use
Since its introduction in the 1970s, CT has become an
important tool in medical imaging to supplement X-rays
and medical ultrasonography. Although it is still quite
expensive, it is the gold standard in the diagnosis of a
large number of different disease entities.
It has more recently used for preventive medicine or
screening for disease, for example CT colonography for
patients with a high risk of colon cancer.
Although a number of institutions offer full-body scans
for the general population, this practice remains
controversial due to its lack of proven benefit, cost,
radiation exposure.
20. AdvantagesAdvantages
First ,CT completely eliminates the superimposition of
images of structures outside the area of interest.
Second, because of the inherent high-contrast
resolution of CT, differences between tissues that differ
in physical density by less than 1% can be distinguished.
Third, data from a single CT imaging procedure
consisting of either multiple contiguous or one helical
scan can be viewed as images in the axial, coronal, or
sagittal planes, depending on the diagnostic task. This is
referred to as multiplanar reformatted imaging.
21. Hazards : Adverse reactions toHazards : Adverse reactions to
contrast agentscontrast agents
Because CT scans rely on intravenously administered
contrast agents in order to provide superior image
quality, there is a low but non-negligible level of risk
associated with the contrast agents themselves.
Certain patients may experience severe and potentially
life-threatening allergic reactions to the contrast dye.
The contrast agent may also induce kidney damage. The
risk of this is increased with patients who have
preexisting renal insufficiency, preexisting diabetes, or
reduced intravascular volume.
22. In general, if a patient has normal kidney
function, then the risks of contrast nephropathy
are negligible.
Patients with mild kidney impairment are
usually advised to ensure full hydration for
several hours before and after the injection.
For moderate kidney failure, the use of
iodinated contrast should be avoided; this may
mean using an alternative technique instead of
CT e.g. MRI.
24. X-ray slice data is generated using an X-ray
source that rotates around the object; X-ray
sensors are positioned on the opposite side of
the circle from the X-ray source.
Many data scans are progressively taken as the
object is gradually passed through the gantry.
They are combined together by the
mathematical procedure known as tomographic
reconstruction.
25. contrast materials such as intravenous iodinated
contrast are used.
This is useful to highlight structures such as
blood vessels that otherwise would be difficult
to delineate from their surroundings.
Using contrast material can also help to obtain
functional information about tissues.
26. WindowingWindowing
Windowing is the process of using the calculated
Hounsfield units to make an image.
The various radiodensity amplitudes are mapped to 256
shades of gray. These shades of gray can be distributed
over a wide range of HU values to get an overview of
structures.
Alternatively, these shades of gray can be distributed
over a narrow range of HU values (called a "narrow
window") centered over the average HU value of a
particular structure to be evaluated. In this way,
variations in the internal makeup of the structure can be
discerned. This is a commonly used image processing
technique known as contrast compression.
27. For example, to evaluate the abdomen in order
to find Smalll masses in the liver, one might use
liver windows . Choosing 70 HU as an average
HU value for liver, the shades of gray can be
distributed over a narrow window or range.
One could use 170 HU as the narrow window,
with 85 HU above and 85 HU below it, with 70
HU average value; Therefore the liver window
would extend from -15 HU to +155 HU.
28. All the shades of gray for the image would be
distributed in this range of Hounsfield values.
Any HU value below -15 would be pure black,
and any HU value above 155 HU would be pure
white in this example.
Using this same logic, bone windows would use
a "wide window" (to evaluate everything from
fat-containing medullary bone that contains the
marrow, to the dense cortical bone) .
29. ArtifactsArtifacts
Although CT is a relatively accurate test, it is
liable to produce artifacts, such as the following:
Aliasing Artifact or Streaks
These appear as dark lines which radiate away
from sharp corners.
It occurs because it is impossible for the
scanner to 'sample' or take enough projections
of the object, which is usually metallic. It can
also occur when aninsufficient penetration of
the x-ray occurs.
30. Ring Artifact
Probably the most common mechanical artifact,
the image of one or many 'rings' appears within
an image. This is due to a detector fault.
Noise Artifact
This appears as gaining on the image and is
caused by a low signal to noise ratio. This
occurs more commonly when a thin slice
thickness is used. It can also occur when the kV
or mA is too low.
31. Motion Artifact
This is seen as blurring which is
caused by patient movement.
This is not so much a problem
these days with faster scanning
times in the use of MDCT.
Beam Hardening
This can give a 'cupped
appearance'. It occurs when
there is more attenuation in
the center of the object than
around the edge.This is easily
corrected by filtration .
32. Three dimensional (3D)Three dimensional (3D)
Image ReconstructionImage Reconstruction
The principle
Because contemporary CT scanners offer
isotropic, or near isotropic resolution, display of
images does not need to be restricted to the
conventional axial images.
Instead, it is possible for a software program to
build a volume by 'stacking' the individual slices
one on top of the other. The program may then
display the volume in an alternative manner.
33. Multiplanar reconstructionMultiplanar reconstruction
Multiplanar reconstruction (MPR) is the
simplest method of reconstruction.
A volume is built by stacking the axial slices.
The software then cuts slices through the
volume in a different plane (usually orthogonal).
Optionally, a special projection method, such
as maximum-intensity projection (MIP) or
minimum-intensity projection (mIP), can be
used to build the reconstructed slices.
34. Fig.showing 1 3D and 3 MPR viewsFig.showing 1 3D and 3 MPR views
35. MPR is frequently used for examining the spine. Axial
images through the spine will only show one vertebral
body at a time and cannot reliably show the
intervertebral discs. By reformatting the volume, it
becomes much easier to visualise the position of one
vertebral body in relation to the others.
MIP reconstructions enhance areas of high radiodensity,
and so are useful for angiographic studies.
mIP reconstructions tend to enhance air spaces so are
useful for assessing lung structure.
36. 3D rendering techniques3D rendering techniques
Surface rendering
A threshold value of radiodensity is chosen by the
operator (e.g. a level that corresponds to bone). A
threshold level is set, using edge detection image
processing algorithms.
From this, a 3-dimensional model can be constructed
and displayed on screen.
Multiple models can be constructed from various
different thresholds, allowing different colors to
represent each anatomical component such as bone,
muscle, and cartilage.
◦ However, the interior structure of each element is not visible in
this mode of operation
37. Volume rendering
Surface rendering is limited in that it will only display
surfaces which meet a threshold density, and will only
display the surface that is closest to the imaginary
viewer.
In volume rendering, transparency and colors are used
to allow a better representation of the volume to be
shown in a single image - e.g. the bones of the pelvis
could be displayed as semi-transparent, so that even at
an oblique angle, one part of the image does not
conceal another.
38. 3D rendering software3D rendering software
Some examples of CT 3D surface
rendering software include
Mimics, 3D doctor, Amira....etc
Some examples of CT 3D volume
rendering software include 3D
doctor, ScanDoc-3D....etc
39. Image segmentationImage segmentation
Segmentation (image processing)
Where different structures have similar
radiodensity, it can become impossible to
separate them simply by adjusting volume
rendering parameters. The solution is called
segmentation, a manual or automatic procedure
that can remove the unwanted structures from
the image.
40. A volume rendering of this volumeA volume rendering of this volume
clearly shows the high density bonesclearly shows the high density bones
Bone reconstructed in 3D
41. Using a segmentation tool to removeUsing a segmentation tool to remove
the bone to show brain vesselsthe bone to show brain vessels
Brain vessels reconstructed in 3D after bone has been removed
by segmentation
42. Conclusions.Conclusions.
This paper discusses the possibilities of
computer tomography in human
body/materials research. In this large
interdisciplinary field not only high quality
2D and 3D images of the internal
structure of the body/material can be
obtained but with intelligent processing of
the data even quantitative information.