MDCT Principles and Applications- Avinesh ShresthaAvinesh Shrestha
Multidetector CT (MDCT) is one of the most commonly used imaging modality in the field of Radiology. Development and advancement in MDCT has made it's application as a major component in diagnosis and treatment planning of multitude of disease across the planet. This presentation briefly describes its basic principle and it's wide variety of application in medical imaging.
MDCT Principles and Applications- Avinesh ShresthaAvinesh Shrestha
Multidetector CT (MDCT) is one of the most commonly used imaging modality in the field of Radiology. Development and advancement in MDCT has made it's application as a major component in diagnosis and treatment planning of multitude of disease across the planet. This presentation briefly describes its basic principle and it's wide variety of application in medical imaging.
Rad 206 p12 Fundamentals of Imaging - Control of Scatter Radiationsehlawi
Fundamentals of Imaging
This course will provide you with the principles involved in the formation and recording of the radiologic image in both conventional and digital imaging systems as well as the principles of image quality assessment.
Control of Scatter Radiation
IT REVIEWS Introduction and definition INTRODUCTION
BEAM-RESTRICTING DEVICES
ADVANTAGES AND DISADVANTAGES
TECHNIQUE
FILTERS
AND PHYSICS BEHIND IT AND LIGHT AND MIRROR ARRANGMENT CLEARLY EXPLAINED WELL.IT ALSO INCLUES THE FLITERS CLASSIFICATION AND COLLIMATORS CLASSIFICATION.
COLLIMATIORS ARE NOTHING BUT BEAM ALINERS
CDSCO and Phamacovigilance {Regulatory body in India}NEHA GUPTA
The Central Drugs Standard Control Organization (CDSCO) is India's national regulatory body for pharmaceuticals and medical devices. Operating under the Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, the CDSCO is responsible for approving new drugs, conducting clinical trials, setting standards for drugs, controlling the quality of imported drugs, and coordinating the activities of State Drug Control Organizations by providing expert advice.
Pharmacovigilance, on the other hand, is the science and activities related to the detection, assessment, understanding, and prevention of adverse effects or any other drug-related problems. The primary aim of pharmacovigilance is to ensure the safety and efficacy of medicines, thereby protecting public health.
In India, pharmacovigilance activities are monitored by the Pharmacovigilance Programme of India (PvPI), which works closely with CDSCO to collect, analyze, and act upon data regarding adverse drug reactions (ADRs). Together, they play a critical role in ensuring that the benefits of drugs outweigh their risks, maintaining high standards of patient safety, and promoting the rational use of medicines.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Basavarajeeyam is a Sreshta Sangraha grantha (Compiled book ), written by Neelkanta kotturu Basavaraja Virachita. It contains 25 Prakaranas, First 24 Chapters related to Rogas& 25th to Rasadravyas.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
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.
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
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
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
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
2. INTRODUCTION
• The radiographic grid are the devices that
reduce the amount of scatterred
radiation reaching the image receptor
• It consists of a series of lead foil strips
separated by X-RAY transparent spacers.
• Most effective way of removing scatter
radiation from large radiographic fields
• function is to improve image contrast
3. INTRODUCTION
• The grid is an extremely effective device for
reducing the level of scattered radiation that
reaches to the image receptor (IR)
• A carefully fabricated series of section of
radio-opaque material (grid stripes)
alternating with the section of radiolucent
materials (interspace materials)
• the grid is positioned between the patient
and image receptor
• the grid is designed to transmit only those
xrays whose direction is on straight line from
source to IR.
• Scattered radiations absorbed in the grid
materials.
4. HISTORY
• The grid was first invented
in 1913 by DR. GUSTAV
BUCKY.
• consisted of wide strips of
lead approx. 2cm apart in
crisscross pattern
5. HISTORY
• In 1920 the grid was improved by DR. HOLLIS POTTER.
• He re-alligned the lead strips so they would run in only one direction
• He made the lead strips thinner and therefore less obvious on th
image and design a device that allowed the grid to move during the
exposure (now known as potter bucky grid)
6. PRINCIPLE
• When the primary beam interact with the
patients body, the scattered radiation are
produced that may or may not be absorbed
depending on angle of incidence and
physical characteristics of the grid.
• If the angle of scattered beam is greater
enough to interact with lead strips , it is
absorbed.
• If the angle is small, the scattered beam will
be transmitted as the primary beam.
• Grid removes the scattered radiation before
it reaches to the film, therefore it improves
contrast.
7. IDEAL GRID
• Should pass all the primary photons i.e photons coming from focal
spot
• Should block all the secondary photons i.e photons not coming from
focal spot
8. GRID CONSTRUCTION
• 3 Different aspects
1. GRID RATIO
2. GRID FREQUENCY
3. GRID MATERIALS
INTERSPACE MATERIALS
LEAD STRIPS
9. GRID RATIO
• A grid has 3 dimensions
1. Thickness of lead stripe (T)
2. Width of interspace materials
(D)
3. Height of grid (H)
• SO GRID RATIO = H/D
10. GRID RATIO
• Higher the grid ratio the more clean of scatter radiation.
• Grid Ratio is expressed as X:1
• If H is kept constant and D is decreased the grid ratio will increase.
• TYPICAL VALUES:
1. 5:1 TO 16:1 - in general use
2. 3:1 TO 5:1 -- in mammography
11. GRID FREQUENCY
• Defined as number of lead strips per inch or
centimeter
• usually ranges from 60-200 lines / inch
• most commonly we use 85 - 100 lines / inch
• mammographic grids- 200 lines/ inch
• HIGH FREQUENCY GRIDS
more and thinner strips
high radiographic techniques
higher patient dose
no signifcant grid lines on the image
12. GRID MATERIALS
• A series of radioopaque lead stripes with alternate radiolucent
materials
1. INTERSPACE MATERIALS
• Maintains the precise separation between strips
• Generally constructed from aluminium or plastic fiber
• Aluminium does not absorb moisture as plastic fibre does
• Produce less visible grid lines on the radiograph
• But it increases the absorption of primary xrays
• so we require higher mAs -- higher patient dose
• FIBER MATERIAL are preferred where their application can
contribute to lower patient dose-- mammography
13. GRID STRIPS
• Should be thick enough to absorb scatter radiation and thin enough
to allow primary radiation
• height varies from 2-5 mm
LEAD IS WIDELY USED BECAUSE
1. Easy to shape
2. Relatively inexpensive
3. High atomic number and high mass density
Tungsten , Platinum, Gold, Uranium can also be used but none of
them has desirable characters as that of lead
14. GRID PERFORMANCE
• Principle function of grid is to improve contrast
• Therre are 3 methods of evaluating perforemance
1. Contrast improvement factor
2. Bucky factor
3. Selectivity
15. CONTRAST IMPROVEMENT FACTOR
• Measures improvement in image quality when grid is used
• It compares contrast improvement with a grid to that without a grid
• represented by letter K
• k= 1 means noimprovement
• most grids have k= 1.5-2.5
• K= contrast with grid/ contrast without grid
• It is complex function of-- 1)XRAY emission spectrum 2) Patient
thickness 3)Tissue irradiated
16. BUCKY FACTOR
• Also called as grid factor
• B= Patient dose with grid/without grid
• Higher the grid ratio higher will be the bucky factor
• Means higher the H and/ lower the D (higher grid ratio) higher will be
the B and higher will be the patient dose
17. GRID SELECTIVITY
• Although grids are allowed to absorb the scatter radiation, they also
asorb some primary radiation called as grid cutoff
• Grids that absorb greater percentage of scatter radiation than primary
are descibed to have greatter degree of selectivity
• grids with higher lead content will have higher selectivity.
• SIGMA (E)= Primary radiation transmitted / scatter radiation
transmitted
• HEAVY GRID- MORE LEAD - HIGHER SELECTIVITY - HIGH CONTRAST
IMPROVEMENT- MORE EFFICIENT
18. GRID TYPES
1. LINEAR
• Parallel
• Crossed
1. FOCUSSED
2. MOVING
• Single stroke
• Reciprocating
• Oscillating
19. LINEAR GRIDS
1) PARLLEL
• Lead and interspace material parallel
• only reduces scatter in the direction of the grid lines
2) CROSSED
• Two linear grids at right angle
• more efficient than parallel
• DR. Bucky originally used it
• grid cutoff is primary disadvantage
• xray tube and table should be perfectly alligned
• central ray must be perfectly alligned with centre of
grid
20. FOCUSSED GRIDS
• Designed to minimize grid cutoff
• Lead strips lie on the imaginary radial lines
of a circle centered at the focal spot so
they can coincide with the divergence of
the xray beam
• if positioned properly-- no grid cutoff
• more difficult to manufacture than parallel
• Must be positioned at a particular distance
called SOURCE TO IMAGE DISTANCE (SID).
• normally SID = 100cm in table and 180 cm
in chest radiography
21. MOVING GRIDS
• GriD lines are visible if primary x rays are absorbed even grid strips
are very small
• invented by Hollis E Potter in 1920 with simple idea of moving the
grid while exposure is made
• usually focussed grids are used
• motion blurs out the grid strips.
Disadavntages-
• mechanical problems may occur
• costly
• increase the patient radiation dose
22. MAMMOGRAPHIC GRID
• Moving grid with ratio of 4:1 to 5:1
• grid frequency - 30-40 lines/cm
• bucky factor= 2-3
• Does not compromise resolution but increase pt. dose
• HTC grid is the choice
23. HIGH TRANSMISSION CELLULAR GRID(HTC)
• Reduces scatter radiation in 2
dimension
• Grid strips are made of copper
• interspace material is air
• physical dimensions= 3.8:1
25. 1)OFF LEVEL
• This occurs when central ray
is angled across the axis of
the grid strips
• Therefore central rays are
incident on the grid at an
angle
• Grid cut-off will occur
• Arises due to improper tube
position
26. 2) OFF CENTER
• If the central ray is not properly
centered on the centermost
interspace of the grid i.e lateral
shifting of grid
• Common problem with mobile
XRAY tables or ceiling suspended
tubes
• Also called lateral decentering
• Arises due to improper tube
position
27. 3) OFF FOCUSED
• Due to unspecified SID selection
in case of focused grid
• if SID increases the grid cutoff
increases
• Grid cutoff is more severe at the
edge than center
• This problem will not occur if all
chest radiographs are taken at
180 cmSID and all table
radiographs at 100 cm SID
28. 4)UPSIDE DOWN
• Major grid problem but will not be noticed easily
• Maximum cutoff on either side of central ray
• Occurs when grid is used upside-down
• So side be checked prio to use
29. 5) COMBINED OFF CENTER & OFF FOCUSED
• Most common
improper grid
position
• mostly occurs
during mobile
radiography
• Resultant
radiograph with
dark on one side
and light on the
other side i.e
uneven exposure
30. GRID SELECTION
• Do not use grid for children
• Grid can be used if thickness is > 10cm
• Moving grid is always better than stationary
• focused > parallel
• Upto 8:1 grid ratio is good for <90kvp and more tha 8:1 for > 90 kvp
• Pt. dose increases with increase in grid ratio
• High ratio grids are used for high kvp examination
• Pt. dose at high kvp is more than at low kvp
31. AIR GAP TECHNIQUE
• Alternative to use of grid
• Involves placing the patient at a
greater object-image receptor
distance
• Image receptor is moved 10-15
cm away from the patient
• So the amount of scatter
reaching the image receptor will
be reduced
• Result is improved contrast
• But disadvantage is loss of
sharpness