The document discusses TomoTherapy's implementation of image-guided adaptive radiation therapy which uses megavoltage CT (MVCT) imaging for patient alignment and deformable image registration between MVCT and diagnostic kVCT images to automatically evaluate changes in patient anatomy and recalculate dose distributions on a daily basis to facilitate adaptive replanning when needed.
Adaptive Radiotherapy at GenesisCare UKGenesisCareUK
A discussion about adaptive radiation therapy, a closed-loop radiation treatment process and how it can improve radiation treatment by systematically monitoring treatment variations and incorporating them to re-optimize the treatment plan early on during the course of treatment.
1.Stereotactic Radiosurgery (SRS)
SRS is a precise and focused delivery of a single, high dose of irradiation to a small and critically located intracranial volume while sparing normal structure
2.Stereotactic Body Radiation Therapy (SBRT)
SBRT is a treatment procedure similar to SRS, except that it deals extra-cranial radiosurgery
3.Flattening Filter Free (FFF) mode
FFF beam is produced without the use of flattening Filter
In the 1990s, several groups studied about FFF high-energy photon beams. The main interest for that, is to increase the dose rate for radiosurgery or the "physics interest”.
Need of increase in dose rate from traditional 300-600 to 1400-2400MU/min to overcome time-inefficiency and to improve patients comfort specially in SRS/SBRT
Flattening Filter Free (FFF) mode
FFF beam is produced without the use of flattening Filter
In the 1990s, several groups studied about FFF high-energy photon beams. The main interest for that, is to increase the dose rate for radiosurgery or the "physics interest”.
Need of increase in dose rate from traditional 300-600 to 1400-2400MU/min to overcome time-inefficiency and to improve patients comfort specially in SRS/SBRT
Conventional radiotherapy treatments are delivered with radiation beams that are of uniform intensity across the field (within the flatness specification limits). Wedges or compensators are used to modify the intensity profile to offset contour in irregularities and produce more uniform composite dose distributions such as in techniques using wedges. This process of changing beam intensity profile to meet the goals of a composite plan is called intensity modulation
IMRT refers to a radiation therapy technique in which nonuniform fluence is delivered to the patient from any given position of the treatment beam to optimize the composite dose distribution. The optimal fluence profiles for a given set of beam directions are determined through inverse planning. The fluence files thus generated are electronically transmitted to the linear accelerator, which is computer controlled, to deliver intensity modulated beams (IMBs) as calculated.
Sharing about “A typical day in the life as Radiation Therapy Technologist (RTT)” includes their roles, responsibilities, duties, working protocols, management, working stress, daily challenges in this modern radiotherapy era. As well as a bit information about how to become a RTT in India.
A summary of recent innovations in radiation oncology focussing on the priniciples of different techniques and their application. An overview of clinical results has also been given
Intensity Modulated Radiation Therapy (IMRT) is an advanced mode of high-precision radiotherapy that uses computer-controlled linear accelerators to deliver precise radiation doses to a malignant tumor or specific areas within the tumor by reducing radiation dose to the nearby normal tissues.
Adaptive Radiotherapy at GenesisCare UKGenesisCareUK
A discussion about adaptive radiation therapy, a closed-loop radiation treatment process and how it can improve radiation treatment by systematically monitoring treatment variations and incorporating them to re-optimize the treatment plan early on during the course of treatment.
1.Stereotactic Radiosurgery (SRS)
SRS is a precise and focused delivery of a single, high dose of irradiation to a small and critically located intracranial volume while sparing normal structure
2.Stereotactic Body Radiation Therapy (SBRT)
SBRT is a treatment procedure similar to SRS, except that it deals extra-cranial radiosurgery
3.Flattening Filter Free (FFF) mode
FFF beam is produced without the use of flattening Filter
In the 1990s, several groups studied about FFF high-energy photon beams. The main interest for that, is to increase the dose rate for radiosurgery or the "physics interest”.
Need of increase in dose rate from traditional 300-600 to 1400-2400MU/min to overcome time-inefficiency and to improve patients comfort specially in SRS/SBRT
Flattening Filter Free (FFF) mode
FFF beam is produced without the use of flattening Filter
In the 1990s, several groups studied about FFF high-energy photon beams. The main interest for that, is to increase the dose rate for radiosurgery or the "physics interest”.
Need of increase in dose rate from traditional 300-600 to 1400-2400MU/min to overcome time-inefficiency and to improve patients comfort specially in SRS/SBRT
Conventional radiotherapy treatments are delivered with radiation beams that are of uniform intensity across the field (within the flatness specification limits). Wedges or compensators are used to modify the intensity profile to offset contour in irregularities and produce more uniform composite dose distributions such as in techniques using wedges. This process of changing beam intensity profile to meet the goals of a composite plan is called intensity modulation
IMRT refers to a radiation therapy technique in which nonuniform fluence is delivered to the patient from any given position of the treatment beam to optimize the composite dose distribution. The optimal fluence profiles for a given set of beam directions are determined through inverse planning. The fluence files thus generated are electronically transmitted to the linear accelerator, which is computer controlled, to deliver intensity modulated beams (IMBs) as calculated.
Sharing about “A typical day in the life as Radiation Therapy Technologist (RTT)” includes their roles, responsibilities, duties, working protocols, management, working stress, daily challenges in this modern radiotherapy era. As well as a bit information about how to become a RTT in India.
A summary of recent innovations in radiation oncology focussing on the priniciples of different techniques and their application. An overview of clinical results has also been given
Intensity Modulated Radiation Therapy (IMRT) is an advanced mode of high-precision radiotherapy that uses computer-controlled linear accelerators to deliver precise radiation doses to a malignant tumor or specific areas within the tumor by reducing radiation dose to the nearby normal tissues.
This workshop is meant to be an introduction to the systematic review process. Further information about systematic reviews was available through a research guide. http://libguides.ucalgary.ca/content.php?pid=593664
Past, present and future of radiotherapy technique in different sites: Breast...Biplab Sarkar
Past, present and future of radiotherapy technique in different sites: Breast, Head and Neck, Brain and Craniospinal irradiation for medduloblastoma and PNET treatment.
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.
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
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
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!
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
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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.
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
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
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
Evaluation of antidepressant activity of clitoris ternatea in animals
Adaptive Radiation Therapy With Tomo Therapy
1. M D Anderson
Cancer Center
Orlando
TomoTherapy’s Implementation of
Image-guided Adaptive Radiation
Therapy
Katja Langen, PhD
Research supported by TomoTherapy Inc.
2. Today’s Lecture
• Introduction to helical tomotherapy
• Image guidance with TomoTherapy
• Adaptive radiation therapy with TomoTherapy
10. Fan Beam lateral
longitudinal
400 mm 10, 25, or 50 mm
lateral longitudinal
11. Helical Tomotherapy ?
from: W. Kalender, Computed Tomography: Fundamentals,
System Technology, Image Quality, Applications
12. Delivery
- 51 projections per
rotation: 360 º /51=7 º
-Temporal modulation
leaf opening time
during projection
13. Head + Neck Delivery Instructions
(Sinograms)
P
r
Prostate -Typical gantry rotation:
o 15-20 seconds
j
e
c
t
-Typical treatment time:
i Prostate: 5 Min
o H+N: 7 Min
n
s
64 Leafs
16. Megavoltage CT images
6 MV Accelerator
(tuned to 3.5 MV for MVCT)
Primary Collimator
( 4 mm Slice Width)
Binary MLC
85cm (all leafs open during MVCT)
User can adjust:
TF
OV -Scan range
C
cm
40 -Pitch
Approximately 50cm
Courtesy of:
TomoTherapy, Inc .
20. Terminology
Image-guided Radiation Therapy (IGRT):
Use images to position patient
-Portal images, Ultrasound, CT-based
Image-guided Radiation Therapy (IGRT) with
TomoTherapy:
Megavoltage CT (MVCT) based
22. Helical Tomotherapy:
MVCT Imaging Performance Characterization
• AAPM CT Phantom [Cardinal Health, Hicksville, NY].
• Noise
• Uniformity
• Spatial Resolution
• Dosimetry
• Multiple Scan Average Dose (MSAD) in 20 cm
diameter acrylic phantom
Meeks et al., Med Phys, 32, pp 2673
23. Noise
Expressed as % of µwater
Mean ROI ROI Standard
Matrix Pitch Noise
"CT #" Deviation
1.0 1024 25.4 2.7
256 1.6 1026 an
worse th 25.4 2.7
-
2.4 1021lues
ch va 25.3 2.7
t
of pi
1.0 ependent 1028 35.4 3.7
nd
512 ix – i
tr 1.6 1027 35.5 3.7
co n ma
w ith re nners 2.4 1029 36.2 3.8
Increases CT sca
c
diag n o s ti 1.0 1025 43.2 4.5
768 1.6 1025 43.8 4.6
2.4 1026 43.3 4.6
AcQSim
1.0 1005 18 1.9
512
Meeks et al., Med Phys, 32, pp 2673
24. Uniformity
Maximum Peripheral to Central Deviation
Matrix Pitch Maximum Uniformity Mean Mean
Peripheral Index Center Peripheral
rs
Variation (%) "CT" "CT"
T sc anne
256 1.0 0.99 99.5 1015 s ti c
1025 C
o
iagn1027
1019 d
1.6 0.97 99.6
a ble to
2.4 1.03 99.5 compar 1013 1022
v a lues
–
512 1.0 1.00
matrix 99.5 1020 1029
econ
1.6 h/r 0.90 99.6 1019 1028
f pitc
ndent o 2.4 1.04 99.5 1021 1031
I ndepe
768 1.0 0.94 99.5 1019 1027
1.6 0.80 99.6 1019 1026
2.4 0.89 99.6 1019 1027
AcQSim 1.0 0.55 99.6 1006 1005
512
Meeks et al., Med Phys, 32, pp 2673
25. Spatial Resolution: Qualitative Determination
256x256 matrix 512x512 matrix
No holes resolved Visible resolution ~1.5 mm
Visible resolution > 1.75 mm
768x768 matrix
Visible resolution ~1.25 mm
Meeks et al.,
Med Phys, 32, pp 2673
26. Meeks et al.,
Contrast Detail Med Phys, 32,
pp 2673
18
16 25.4 mm
14 19.1 mm
12
Diameter (mm)
12.7 mm
10 9.5 mm
8 6.4 mm
3.2 mm
6 Visible 5% difference
4
2
Not Visible
0
0 10 20 30 40 50 60 70 80 90 100 110
% Electron Density Difference
29. Summary
• Uniformity is comparable to diagnostic CT scanners while noise is
worse
• Spatial resolution using 512x512 matrix is ~1.5 mm
• Dose: ~1 cGy for “fine” setting (pitch of 1) ; dose decreases with
“looser” pitch
• Image Quality is acceptable for patient alignment, and is also
acceptable for delineation of many soft tissue structures.
Meeks et al., Med Phys, 32, pp 2673
30. Average In-Room Times
• 5 minutes for setup
IGRT
• 3-5 minutes MVCT scan
• 5 minutes reconstruction and registering MVCT
to KVCT and shift patient
• 5-10 minutes beam on time
• 5 minutes assist patient out
38. Conclusions of alignment study
Implanted marker based alignment have
least inter-user variability
Anatomy-based alignments outperform
contour-based alignments
Langen et al., IJROBP, 62, pp 1517
39. Head and Neck alignment: bony anatomy
MVCT
Spinal Cord
Base of skull not aligned
aligned
46. Terminology
Adaptive Radiation Therapy (ART):
Use information from images to change subsequent
treatments
-Change margin based on observed setup/organ
motion
-Use images to evaluate dosimetry (dose-guided, dose
compensation…)
Adaptive Radiation Therapy (ART) with TomoTherapy:
Using MVCT images to evaluate dosimetry on daily
basis
47. Adaptive Radiation Therapy:
need accurate HU
numbers
Acquire MVCT
↓
Recalculate dose distribution on MVCT
↓
Add dose distribution to calculate cumulative dose
↓
Compare with plan
↓
need deformable
Adapt plan
image registration
51. MVCT Integrity ?
Does the calibration change with time ?
Does calibration change with phantom arrangement ?
Does the calibration change with MVCT pitch ?
59. Dose re-computation end-to-end tests
Deformed anatomy ?
Plan 2 Plan 2, Plan 2,
Deformation 1 Deformation 2
Point of ion chamber measurement
60. Dose re-computation end-to-end tests
Meas. Diff (%) Re-calc. Diff (%)
Plan 1, Def 1 + 2.7 +2.9
Plan 1, Def 2 -10.5 -9.3
Plan 2, Def 1 +3.3 +3.2
Plan 1, Def 2 -11.5 -10.8
61. Conclusions
- MVCT numbers are reproducible
MVCT to electron density calibration is reliable
- Phantom end-to-end test results are
typically
within 1 % of plan results
MVCT images can be used for
reliable dose computations
Langen et al.: Use of mega voltage CT (MVCT) images for
dose computations. PMB, 50, pp 4259
62. Daily-IGRT, why ART ?
Deformation in the Pelvis
Same patient, different days
Dosimetric consequence ?
63. Evaluate dosimetric consequence:
Dose Re-calculation
Use pre-treatment MVCT
Recalculate plan based on planned MLC pattern
Recalculate Dose on MVCT image
64. Deformation in the Pelvis
Evaluate dosimetric consequence
Obtain MVCT MVCT contours Dose recalculation
66. Deformation in the Pelvis
Plan DVH
39 “true” DVHs
1) Requires manual contouring
2) Need deformable image registration to
calculated the cumulative DVH
67. Deformable image registration
Relate voxel location x to its location in the second
image (at a later time t) using a displacement
vector u(x,t)
x’(x,t)=x+u(x,t)
Algorithm minimizes ∑u and differences in HU units
Lu et al. , Phys Med Biol, 49, pp 3067, 2004
68. MVCT to kVCT
deformable image registration
Algorithm requires same HU for same voxel
in MVCT and kVCT
MVCT are noisier
=> apply edge-preserving smoothing
=> MVCT numbers ≠ kVCT numbers
intensity histogram calibration
Lu et al. , Phys Med Biol, submitted, 2006
69. MVCT to kVCT
deformable image registration
Algorithm maps each MVCT voxel to kVCT
Algorithm can map each kVCT voxel to MVCT
⇒ can be used for automatic
contouring of MVCT
⇒ automatically generated MVCT contours can be
used to visualize deformation map
Lu et al. , Phys Med Biol, submitted, 2006
73. Accuracy of automatic H+N MVCT
contours ?
Parotids: Visual inspection of automatic
contours
kVCT contours:
MVCT contours:
74. Accuracy of automatic H+N MVCT
contours ?
Parotids: Visual inspection of automatic
contours
- 6 patients, 150 MVCT scans, 2 physician
Conclusion: The parotid contours generated
by the deformable algorithm correlate with the
location of these structures on the daily
MVCT images.
Submitted to ASTRO 06, Manon et al.
78. Parotid dose during treatment course
Numerical Analysis:
-6 patients, 150 MVCT scans
Conclusion:
At end of treatment: mean parotid dose was
on average 7.5 Gy higher than planned
Range:1.6-16.4 Gy
Submitted to ASTRO 06, Manon et al.
83. Generate adaptive plan
-Use kVCT-kVCT deformable
registration to transfer original structures
to second kVCT
-Physician reviewed structures
-Generate new plan Limit dose to
over-dosed parotid region
84. Rt. Parotid DVH (after 17 Txs)
Medium dose High dose
10-20 Gy > 20 Gy
Low dose
0-10 Gy
Dose difference mostly in
10-20 Gy region
85. Parotid DVH
Generate contour
that corresponds to
10-20 Gy region
88. WHAT IF SCENARIOS….compare
-Original Plan P1(35)
-Plan 1 delivered for 17 fx + Plan 2 for 18 fx
Planned to deliver with adaptive RT
D1(17)+P2(18)
-Actual delivery (Plan 1-17 fx and Plan 2-18 fx)
D1(17)+D2(18)
-without adaptive RT, Plan 1 only D1(35)
93. Conclusion
Opportunities Challenges
- Assess consequence - When to adapt plan ?
of deformation
- How often ?
- Correct differences
between delivered and - Verify accuracy of
planned dose in adaptive deformable registration
Plan - Shrinking volumes ?
94. Thanks !
MD Anderson: TomoTherapy:
Sanford Meeks Gustavo Olivera
Tom Wagner Jason Haimerl
Twyla Willoughby Ken Ruchala
Omar Zeidan Weigu Lu
Amish Shah Sam Jeswani
Arati Limaye Quan Chen
Patrick Kupelian Eric Schnarr
Rafael Mañon
Daniel Buchholz
Alan Forbes
Wayne Jenkins