Treatment Modalities for Brain Disorders

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Treatment Modalities for Brain Disorders
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Existing Treatment Modalities

• Craniotomy
• Chemotherapy
• Brachytherapy
• Whole brain radiation
• XKnife
• Fractionated linac treatment radiotherapy
• Gamma Knife surgery radiosurgery

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Craniotomy description
A craniotomy is the surgical removal of a section
of bone (bone flap) from the skull for the
purpose of operating on the underlying tissues,
usually the brain The bone flap is replaced at
the end of the procedure Craniotomy is used for
many different procedures within the head,
including trauma, tumor, infection, aneurysm,
etc.
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Craniotomy indications
Size tumor mass 3.5cm or larger Location
located on outer surface Patient age and health
able to withstand trauma of surgery Neurosurgeons
familiarity and preference Used to treat Brain
tumors Blood clots Cerebral aneurysms AVMs Brain
abscesses Head injury
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Craniotomy advantages

• Complete and immediate removal of tumor
• Provides access to disease site for brachytherapy
  or seed implantation
• Improved outcomes when combined with follow-up
  Gamma Knife surgery1

1 (Reference to come)
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Craniotomy disadvantages
Higher incidence of mortality and morbidity than
non-invasive treatment methods Requires strong
surgical skill set acquired over
time Significantly longer hospital stay and
recovery time AVM resection may require up to 5
operations Reduced quality of life Greater
incidence of complications and impaired brain
functions Higher costs
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Recovery time for craniotomy vs. radiosurgery
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Chemotherapy description

• Chemotherapy refers to medicines that can kill or
  control cancer
• Chemotherapy medicines target and treat a
  specific area affected by cancer
• Chemotherapy is a systemic treatment, which means
  it is a treatment that affects the whole body
• There are many kinds of chemotherapy, and the
  medicine chosen will depend on the type and the
  extent of the cancer, as well as the potential
  side effects of the medicine
• Each medicine will have its own specific side
  effects

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Chemotherapy indications
Chemotherapy is used to to control the growth of
the cancer to relieve the symptoms or pain caused
by the cancer Some types of cancer respond better
to chemotherapy than others Leukemia Lymphoma Bre
ast cancer Colorectal cancer
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Chemotherapy advantages

• Oral medication more convenient for patients
  (although also administered by shot)
• Currently researching more effective treatments
  to effect cures at molecular level

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Chemotherapy disadvantages
Cant treat brain cancer effectively Chemotherapy
affects both cancer cells and normal body
tissues Most side effects are temporary and
resolve when treatment ends Common complications
include Bone marrow suppression Hair
loss Nausea Fatigue
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Brachytherapy description

• Brachytherapy is a treatment method in which
  sealed radioactive seeds or sources are placed in
  or near tumors
• The radioactive sources deliver high local doses
  of radiation to tumor cells while minimizing the
  dose to surrounding normal tissue
• The depth of penetration of the emitted
  radiation, the type of radiation emitted, and the
  time course over which the radiation is delivered
  to achieve a particular dose are determined by
  the characteristics of the isotope selected

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Brachytherapy indications
Recurrent or metastatic brain tumors Deliver
treatment and minimize risk of damaging healthy
tissue in patients who have already undergone
external radiation therapy There are two primary
ways of using brachytherapy in treating brain
metastases Treat patients aggressively for an
initial tumor Provide radiation boosts following
external beam radiation or surgery
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Brachytherapy advantages

• Use of brachytherapy in combination with other
  treatments which remove a substantial portion of
  the cancerous tumor offer promise
• When a metastasis recurs, therapeutic options are
  limited brachytherapy allows re-irradiation

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Brachytherapy disadvantages
While less invasive delivery systems are being
investigated, some sort of highly invasive
surgical placement is currently required for
placement of the radiation seed
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Whole brain radiation description
Radiation therapy is a common treatment for brain
tumors and can be combined with surgery or
radiosurgery Radiation therapy affects both
normal and tumor cells, but normal cells are
thought to be more capable of repairing
themselves As the therapy continues, the tumor
cells should die and eventually shrink Radiation
therapy does not remove the tumor
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Whole brain radiation indications
Whole brain irradiation is frequently prescribed
for patients with brain metastases After
surgery for highly malignant tumors Instead of
surgery for inoperable tumors Residual tumor
after treatment
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Whole brain radiation advantages

• Symptoms caused by metastatic tumors in the brain
  usually respond to whole brain radiation therapy
• Different studies have reported response rates of
  50 to 70 percent
• Can attack microscopic disease not yet visible to
  current diagnostic studies

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Whole brain radiation combination

• Stereotactic radiosurgery can be combined with
  whole brain radiation therapy for brain
  metastases
• The whole brain radiation therapy will treat the
  visible metastases and any presumed microscopic
  tumor deposits as well
• Whole brain radiation therapy is given as a low
  dose to a larger volume that includes the tumor
  as well as the area of possible tumor spread,
  while stereotactic radiosurgery is a high dose
  boost given to a very small volume and targeted
  only within the tumor itself
• The two treatment techniques are complementary in
  achieving control of metastases to the brain

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Whole brain radiation disadvantages
Side effects will depend on the type of radiation
received, the amount of the surface of the brain
targeted, the site targeted and the total dose of
radiation In general, there will be hair loss,
skin irritation, possible hearing problems,
nausea, vomiting, loss of appetite and neurologic
effects The most prevalent side effect is fatigue
which may last through treatment and for many
months afterwards The neurologic effects most
affecting quality of life are memory and speech
problems Radiation therapy is not recommended
for young children as it may cause a deficit in
intellectual development
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Fractionated linac treatment radiotherapy

• About half of all patients with cancer are
  treated with radiotherapy and have a greater rate
  of success than chemotherapy, a lower risk of
  side effects and very few major side effects
• Radiation or radiotherapy uses high-energy rays
  to kill cancer cells, shrink tumors and prevent
  cancer cells from growing and spreading
• Radiation can be given internally (brachytherapy)
  or externally with the external beam being the
  most common type of radiation treatment

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The difference between radiotherapy and
radiosurgery
Radiotherapy is an extended treatment program
using fractionated radiation over multiple
sessions Radiotherapy is the preferred solution
for treating the body Radiosurgery is a
single-session stereotactic procedure performed
by a neurosurgeon-radiation oncologist team using
radiation to destroy a target in the
brain Radiosurgery is preferred for the brain and
spine because it is a precise, single-dose
procedure
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Radiotherapy advantages

• The survival rate for patients with malignant
  tumors (e.g., anaplastic astrocytoma,
  glioblastoma multiform) more than doubles with
  radiation therapy, and it can prolong life for
  patients with low-grade gliomas as well

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Radiotherapy disadvantages
Fractionated radiotherapy must be administered in
multiple sessions rather than a single session
like radiosurgery Radiotherapy devices are not as
accurate as Leksell Gamma Knife for targets in
the brain
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Radiotherapy machines

• Radiotherapy machines claiming efficacy for brain
  treatments include
• Accuray CyberKnife
• BrainLab Novalis
• Varian Trilogy

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Accuray CyberKnife

• Standard linac modified for use on head and spine
• Accuracy is affected by the moving robotic arm
• Patient movement will affect dose delivery
  outcome
• Low output and lack of accuracy requires
  fractionated delivery
• Only one beam size
• Limited directions in which the robot can shoot
• Not proven for small tumors or functional
  disorders

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Brainlab Novalis

• Standard linac modified for use on head and spine
• Claims accuracy of 2mm
• Low output, poor accuracy requires fractionated
  delivery
• Up to 30 treatment sessions
• Only one beam size
• Limited directions in which the unit can shoot
• Frameless design utilizes old mask-based
  fixation
• Not proven for small tumors or functional
  disorders

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Varian Trilogy

• Standard linac modified for use on head and
  spine
• Put into clinical operation in early 2005
• Claims accuracy of .75mm
• All-in-one unit
• Not proven for small tumors or functional
  disorders

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Radionics XKnife

• Standard linac modified for use on head and spine
• No accuracy claims
• Low output, poor accuracy requires fractionated
  delivery
• Up to 30 treatment sessions
• Only one beam size
• Limited directions in which the unit can shoot
• Frameless design utilizes old mask-based
  fixation
• Not proven for small tumors or functional
  disorders

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Elekta Leksell Gamma Knife radiosurgery
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Elekta Leksell Gamma Knife description
Leksell Gamma Knife is a unique radiosurgery
system dedicated to treating the most sensitive
area in the body Non-invasive and gentle to the
patient 201 stationary beams converge through
four different collimators With the robotic
Automatic Positioning system, Gamma Knife can
automatically hit multiple isocenters to
precisely conform to the tumor shape Uses the
head frame to co-register image studies to a
frame-based study which are transferred into
GammaPlan treatment planning mode - helping to
prevent mistakes and saving time
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Elekta Leksell Gamma Knife indications
Vascular disorders Benign tumors Malignant
tumors Functional disorders Ocular disorders
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Elekta Leksell Gamma Knife advantages

• Can be used to treat metastases in surgically
  inaccessible areas of the brain, such as the
  brainstem
• A noninvasive procedure performed on an
  outpatient basis is associated with less
  morbidity than surgery
• Radiosurgery generally is more cost-effective
  than surgery
• Radiosurgery is more accurate than radiotherapy

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Elekta Leksell Gamma Knife accuracy
Guaranteed accurate to 0.3mm for the life of the
equipment Only equipment accurate enough to
routinely treat functional disorders Tracks
target 10 times per second Full MR
compatibility Leksell Coordinate Frame produces
the best image quality and avoids movement
artifacts, providing the highest reliability in
patient precision
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Elekta Leksell Gamma Knife proven radiosurgery
success

• Designed specifically to treat the brain
• Unique delivery system uses 201 collimators for
  maximum accuracy
• Single treatment session
• Over 2000 published peer-reviewed papers
• More than 300,000 patient treated
• 15-year follow up study
• Proven reliability and reproducibility
• Single day surgery
• Faster throughput in planning and treatment
• Only modality proven to treat functional disorders

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