Arnold Chiari Malformation, also known as Chiari type II malformation, is one of a group of brain malformations affecting the cerebellum. Named after Hans Chiari and Julius Arnold, the pathologists who first described the group of malformations. This condition is almosNormally the cerebellum and parts of the brain stem sit in an indented space at the lower rear of the skull, above the foramen magnum (a funnel-like opening to the canal). When part of the cerebellum is located below the foramen magnum, it is called a Chiari malformation. In Arnold Chiari Malformation, both cerebellar and brain stem tissue protrude into the foramen magnum and the cerebellar vermis (the nerve tissue that connects the two halves of the cerebellum) may be only partially complete or absent t always associated with myelomeningocele, the most serious form of spina bifida Dandy-Walker Syndrome (DWS) is a congenital (happening before birth) condition where the cerebellum does not develop normally. The cerebellum is an area at the back of the brain that controls movement and balance. With DWS, parts of the cerebellum may never develop or may be very small. Other parts of the cerebellum become filled with fluid or develop small masses of fluid (cysts). In most cases, a build-up of fluid inside the skull causes the head to get bigger than it should.

1. Arnold Chiari Malformation
And Dandy Walker
Syndrome
Anandhu Baiju
Group#3
8th Semester Asian Medical Institute Kyrgyzstan

2. Arnold Chiari
Malformation

3. Introduction
Arnold Chiari Malformation, also known as Chiari type II malformation, is one of
a group of brain malformations affecting the cerebellum. Named after Hans
Chiari and Julius Arnold, the pathologists who first described the group of
malformations. This condition is almost always associated with
myelomeningocele, the most serious form of spina bifida

4. Clinically Relevant Anatomy
Normally the cerebellum and parts of the brain stem sit in an indented space at
the lower rear of the skull, above the foramen magnum (a funnel-like opening
to the canal). When part of the cerebellum is located below the foramen
magnum, it is called a Chiari malformation. In Arnold Chiari Malformation, both
cerebellar and brain stem tissue protrude into the foramen magnum and the
cerebellar vermis (the nerve tissue that connects the two halves of
the cerebellum) may be only partially complete or absent

5. Clinically Relevant Anatomy
This condition has skull, dural, brain, spinal, and spinal cord manifestations,
including the downward displacement of the medulla, fourth ventricle, and
cerebellum into the cervical spinal canal, as well as elongation of the pons and
fourth ventricle, probably due to a relatively small posterior fossa
The brainstem is elongated and displaced into the opening of the base of the
skull and into the top of the spinal canal. It is often kinked. The brainstem,
cranial nerves and lower portion of the cerebellum may be stretched or
compressed. This means that any of the functions controlled by these areas
may be affected

6. Clinical Presentation
Many people with Arnold Chiari malformation have no obvious symptoms.
Compressive mechanisms are thought to cause symptoms, but it is likely that
stretching of abnormally placed cranial nerves may provoke symptoms. In
babies, the most common symptoms are a weak or absent cry, breathing
difficulties, including stridor, arching of the neck, failure to thrive and feeding or
swallowing difficulties. a weak cry, gagging or vomiting, arm weakness, a stiff
neck, developmental delays, and an inability to gain weight
Blockage of cerebrospinal fluid (CSF) flow may cause the formation of a syrinx,
which can lead to syringomyelia. Central cord symptoms such as hand
weakness, sensory loss, and, in severe cases, paralysis may occur.

7. Clinical Presentation
Common symptoms people with Chiari Type II malformations might experience
are:
• headaches (usually at the back of the head and often made worse by coughing, sneezing
or straining)
• neck pain
• dizziness and balance problems
• hearing loss and/or tinnitus
• muscle weakness and paralysis
• visual problems and nystagmus
• swallowing difficulties
• dysesthesia in the limbs
• problems with hand coordination and fine motor skills.

8. Diagnostic Procedures
The key tests for diagnosis of Arnold Chiari Malformation are MRI and CT
scans. An MRI will show the abnormal CSF flow and configuration and position
of the brain and spinal cord. Antenatal ultrasound imaging shows an
indentation of the frontal bone with an abnormally shaped cerebellum

9. Differential Diagnosis
• The main differential diagnosis is the type of Chiari malformation
• Chiari I malformation does not have a myelomeningocele.
• Chiari III has an occipital and/or high cervical encephalocele.
• Chiari IV has severe cerebellar hypoplasia without displacement of the
cerebellum through the foramen magnum.

10. Epidemiology
It used to be said that Chiari malformations are rare, but with routine use of MR
imaging, Chiari malformation is discovered with increasing frequency. Chiari II
is found in all children with myelomeningocele, although less than one-third
develop symptoms referable to this malformation

11. Physiotherapy Management
Physiotherapy can help with many of the symptoms caused by Arnold Chiari
Malformation:
• Vestibular Rehabilitation is indicated when patients have vestibular problems
• Conservative physiotherapy soft tissue techniques may be of benefit for
cervical pain
• Soft tissue techniques may be of benefit for headaches

12. Surgical Interventions
Treatment of patients with Arnold Chiari malformation is complex due to the
variety and variable severity of malformations, but some patients may require
any of the following surgical interventions : myelomeningocele repair and
management of neurogenic bladder
• ventricular shunting - hydrocephalus usually requires shunting and can
improve the cranial nerve and brainstem function
• craniovertebral decompression may be required in neonates with brainstem
dysfunction if hydrocephalus is not present, or if symptoms and signs do not
improve with shunting. Some older patients with hindbrain herniation or
syringohydromyelia may also benefit from ventricular shunts

13. Prognosis
Many with Type I CM do not show symptoms and do not know they have the
condition. Symptoms vary among individuals, Individuals who have severe
Chiari malformation and have undergone surgery see a reduction in their
symptoms, Even though paralysis may be permanent.

14. Dandy Walker Syndrome

16. What is Dandy-Walker Syndrome?
• Dandy-Walker Syndrome (DWS) is a congenital (happening before birth)
condition where the cerebellum does not develop normally. The cerebellum is
an area at the back of the brain that controls movement and balance.
• With DWS, parts of the cerebellum may never develop or may be very small.
Other parts of the cerebellum become filled with fluid or develop small
masses of fluid (cysts). In most cases, a build-up of fluid inside the skull
causes the head to get bigger than it should.

17. What is Dandy-Walker Syndrome?
• DWS can occur by itself, or along with other types of birth defects. Children
with DWS may also have heart problems, face or limb defects or problems
with vison and hearing. In rare cases, DWS may not be diagnosed until late
childhood or adulthood. DWS can cause delays in both motor and mental
development. The severity of symptoms and long-term outcomes are
different for each child. Some children need a lot of medical care at birth but
go on to live normal lives with few or no long-term effects. Other children may
lose the ability to move parts of their body (paralysis), seizures and problems
with thinking and learning.
• The long-term survival rate for infants with isolated DWS is very good. If
DWS appears with other genetic conditions, outcomes can vary. Early
treatment to support physical and mental development improves a child’s
chances of having the best quality of life possible for their condition

18. What Causes Dandy-Walker Syndrome?
• No one is sure what causes DWS. Scientists do know that certain genetic conditions or other
outside factors may increase the risk of a baby having the disease.
• DWS begins during the first month of pregnancy. As the baby’s cerebellum starts to develop
abnormally, fluid begins to build up. During the pregnancy, malformations and fluid in the
cerebellum continue to grow. The fluid build-up and problems in the brain structure can cause
many neurological and physical symptoms seen at birth and later in childhood.
• No one knows what causes DWS. There are likely many factors that could be a part of its
development. A number of different genetic syndromes are associated with DWS. Certain medical
problems in the mother, such as diabetes, have been associated with the development of DWS.
There is some research that says a baby’s risk for developing DWS increases if the mother is
exposed to certain types of infections or medicines while she is pregnant

21. What are the Signs and Symptoms of Dandy-Walker
Syndrome?
• Too much fluid in the brain
(called hydrocephalus)
• Signs of increased pressure from fluid build-
up in the brain, including irritability
and vomiting (usually seen in older children)
• Large head (called macrocephaly)
• Delayed crawling and walking
• Balance problems
• Stiff muscles
• Trouble with fine motor skills (picking up small
objects, writing)
• Vision problems
• Seizures
• Abnormal breathing
• Jerky eye or neck movements
• Delay in mental development
• Agenesis of the corpus callosum

22. What are the Types of Dandy-Walker Syndrome?
• Malformation. This is the most severe type of DWS. It is usually seen as part of a group with
congenital birth defects. With Dandy-Walker Malformation, some parts of the cerebellum are not
there. Others are enlarged with fluid-filled cysts. Most babies have hydrocephalus and
macrocephaly and need surgery to place a shunt (a hollow tube) into the brain. This will help the
remove extra fluid. These babies are at great risk for having long-term neurological and
developmental problems.
• Variant. This is the mildest form of DWS. It has a wide range of symptoms and outcomes. Babies
with the Dandy-Walker Variant may have less fluid build-up inside their brain. As a result, they will
have less damage to structures in the cerebellum. Babies with this type of DWS are less likely to
need surgery to remove extra fluid from their brains. However, many may still need surgery. Some
children with this type of DWS will go on to have normal intelligence and physical development.
Others may need many surgeries to remove fluid inside the skull. They will also need life-long
physical therapy.

23. How is Dandy-Walker Syndrome Diagnosed?
A variety of prenatal (before birth) tests can help your doctor diagnose DWS:
• Ultrasound: This type of imaging test that can show problems with how your baby’s brain is
forming
• Fetal MRI (magnetic resonance imaging): Non-invasive imaging test to get a clear, more
detailed image of your baby’s organs.

24. Other Tests
• Some congenital conditions are caused by changes in DNA, or a baby’s genetic makeup. The doctors may
suggest genetic testing to find out more about your baby’s DNA either during pregnancy or after birth.
Recommended tests may include:
• Cell-Free fetal DNA testing: A screening test where a sample of your blood is taken to look for copies of fetal
(baby) DNA. A positive result means that there could be problems with the baby’s DNA. It should be confirmed
with another test. A normal result does not mean that there are no underlying genetic problems. Other testing
can be done before or after birth depending on your needs and the needs of the baby.
• Amniocentesis: A medical procedure in which a small amount of amniotic fluid is taken and studied to screen
for genetic problems. This test is usually done in the middle of the second trimester. An amniocentesis can be
used to confirm findings on the cell-free fetal DNA test.
• Testing the baby: After birth, a sample of your baby’s blood is taken to look for chromosome problems. This is
called either a “karyotype” (basic chromosome study), or microarray (a more detailed look at smaller sections
of DNA).

26. Care During Your Pregnancy
Your doctors will watch your pregnancy closely. If the malformation on your baby’s head is very
large, you may need to have a C-section. You will deliver your baby at a hospital that is prepared
to care for high-risk babies. You should discuss your plans for labor and delivery with your
obstetrician. Contact your doctor right away if you have any concerns

27. Treatment
There is no cure for DW and treatment usually involves treating the associated
symptoms. Often, a shunt may be placed when hydrocephalus is diagnosed. A
shunt will help drain excess fluid in the brain to reduce swelling and intracranial
pressure. A compilation of multiple affects may shorten life span. Medications are
often prescribed to control seizures.

28. How is Dandy-Walker Syndrome Treated?
• Although Dandy-Walker syndrome can interfere with everyday life, milder cases don’t always require
treatment—it depends on the severity of the developmental and coordination issues the person is
experiencing.
• Some common treatments for Dandy-Walker syndrome include:
• The surgical implantation of a shunt in the skull: If your child experiences increased intracranial pressure,
doctors may recommend inserting a shunt (a small tube) in the skull to help alleviate pressure. This tube will
drain fluid from the skull and carry it to other areas of the body, where it can be safely absorbed.
• Various therapies: Special education, occupational therapy, speech therapy, and physical therapy can help
your child manage the issues linked to Dandy-Walker syndrome. Talk to your pediatrician about the therapies
that will be most effective for your child.
• Survival and prognosis depend on the severity of the malformation and the presence of other congenital
defects.