Cerebellar Malformations

INTRODUCTION:

Arnold-Chiari malformation is a condition in which the back of the brain (cerebellum) extends down into the upper spinal canal. Children are usually born with this malformation, but it also can develop later in childhood.

TYPES:

There are four types of Arnold-Chiari malformation. Chiari I malformation is the most common type. Chiari type 1 malformations (CM1) occur in the region where the brain and the spinal cord join. In this disorder, the portions of the brain called the cerebellum and/or brainstem lie lower than usual. Often, a portion of the cerebellum called the cerebellar tonsils protrudes out of the base of the skull into the spinal canal. This protrusion causes pressure in the brain, contributing to the symptoms people experience. Chiari II, commonly referred to as the Arnold-Chiari Malformation, is found almost exclusively in children with spina bifida. Chiari type III and IV malformations are extremely rare.

CAUSES:

  • The Chiari malformation is generally thought to be present from birth.
  • in some instances, mild Chiari malformations may result from low CSF pressure.
  • basilar invagination may also be congenital or acquired (from arthritis).
  • Chiari I malformations are a result of the smallest herniation of an otherwise normal hindbrain. The tonsils would normally be round but often become elongated as they protrude down the spinal canal.

SYMPTOMS:

Usually symptoms of Chiari malformations do not appear until early adutlhood but can occasionally be seen in young children. Some common symptoms include headaches, neck pain, dizziness, vision problems, balance problems and muscle weakness. Other symptoms include difficulty swallowing, frequent gagging and choking and, in some cases sleep apnea may be present In infants and young children, difficulty with feeding and swallowing are more common and may result in gagging, drooling and vomiting. Abnormal breathing may occur resulting in the child having slow or noisy breathing similar to snoring in adults. Irritability, head banging and nighttime awakening may all be signs of headache in young infants. Symptoms in older children commonly include headache, spinal curvature, clumsiness and in rare cases difficulty controlling bladder function.

DIAGNOSIS:

When the diagnosis is suspected, the study of choice is an MRI (Magnetic Resonance Imaging). MRI is safe, painless and informative and has greatly improved the diagnosis of Chiari I Malformation. The MR scan is the best way to diagnose a Chiari malformation. The brain and upper spinal cord can be seen from many angles, which permit an accurate diagnosis to be made.

The Chiari I Malformations may also be associated with other disorders such as hydrocephalus (build up of fluid in the ventricles of the brain) or Syringomyelia. Syringomyelia is a disorder in which cerebrospinal fluid enters the spinal cord, forming a cavity known as a syrinx. It is recommended that patients diagnosed with a Chiari Malformation have the entire spine imaged to rule out the presence of a syrinx, since it may be a consideration in treatment and prognosis.

 

Dandy-Walker syndrome

INTRODUCTION:-

Dandy-Walker syndrome (DWS), or Dandy-Walker complex, is a congenital brain malformation involving the cerebellum and the fourth ventricle.Dandy-Walker malformation is characterized by agenesis or complete absence of the cerebellar vermis, cystic dilatation of the fourth ventricle, enlargement of the posterior fossa and cyst formation near the internal base of the skull. A large number of concomitant problems may be present, but Dandy-Walker malformation is recognized whenever these 3 features are found. Approximately 70-90% of patients have hydrocephalus, which often develops postnatal. Dandy-Walker malformation may be associated with atresia of the foramen of Magendie and, possibly, the foramen of Luschka.1, 2,

PREDISPOSING FACTORS

Predisposing factors for Dandy-Walker malformation include gestational exposure to rubella (in the first trimester), cytomegalovirus, toxoplasmosis, warfarin, alcohol, and isotretinoin.

TYPES

The term Dandy-Walker represents not a single entity, but several abnormalities of brain development which coexist. There are, at present, three types of Dandy-Walker complexes.

They are divided into three closely associated forms: DWS malformation, DWS mega cisterna magna and DWS variant.

  • Malformation : The DWS malformation is the most severe presentation of the syndrome. The posterior fossa is enlarged and the tentorium is in high position. There is partial or complete agenesis of the cerebellar vermis. There is also cystic dilation of the fourth ventricle, which fills the posterior fossa. This often involves hydrocephaly and complications due to associated genetic conditions, such as Spina Bifida.
  • Mega cisterna magna : The second type is a mega cisterna magna. The posterior fossa is enlarged but it is secondary to an enlarged cisterna. This form is represented by a large accumulation of CSF in the cisterna magna in the posterior fossa. The cerebellar vermis and the fourth ventricle are normal.
  • Variant : The third type is the variant, which is less severe than the malformation. This form (or forms) represents the most wide-ranging set of symptoms and outcomes of DWS. Many patients who do not fit into the two other categories of DWS are often labeled as variant. The fourth ventricle is only mildly enlarged and there is mild enlargement of the posterior fossa. The cerebellar vermis is hypoplastic and has a variably sized cyst space. This is caused by open communication of the posteroinferior fourth ventricle and the cisterna magna through the enlarged vallecula. Patients exhibit hydrocephalus in 25% of cases and supratentorial CNS variances are uncommon, only present in 20% of cases. There is no torcular-lambdoid inversion, as usually seen in patients with the malformation. The third and lateral ventricles as well as the brain stem are normal

SYMPTOMS

Symptoms, which often occur in early infancy, include slow motor development and progressive enlargement of the skull. In older children, symptoms of increased intracranial pressure such as irritability, vomiting and convulsions and signs of cerebellar dysfunction such as

  • Unsteadiness
  • Lack of muscle coordination or jerky movements of the eyes may occur.

Other symptoms include increased head circumference, bulging at the back of the skull, problems with the nerves that control the eyes, face and neck, and abnormal breathing patterns.

Dandy-Walker syndrome is frequently associated with disorders of other areas of the central nervous system including absence of the corpus callosum, the bundle of axons connecting the two cerebral hemispheres, and malformations of the heart, face, limbs, fingers and toes

TREATMENT

Treatment for individuals with Dandy-Walker syndrome generally consists of treating the associated problems, if needed. A special tube (shunt) to reduce intracranial pressure may be placed inside the skull to control swelling

 

Joubert Syndrome

Joubert syndrome is a rare brain malformation characterized by the absence or underdevelopment of the cerebellar vermis – an area of the brain that controls balance and coordination.

The most common features of Joubert syndrome in infants include abnormally rapid breathing (hyperpnea), jerky eye movements, mental retardation, and the inability to coordinate voluntary muscle movements (ataxia).

Physical deformities may be present, such as extra fingers and toes, cleft lip or palate, and tongue abnormalities. Seizures may also occur. Most cases of Joubert syndrome are sporadic (in other words, no other family member has the disorder), but in some families, Joubert syndrome appears to be inherited via a recessive gene.

Other Therapy

A child’s emotional and social development can be deeply affected by physical disabilities . For their all round development:-

  • Physical therapy is imperative so as to ensure maximum functional independence.
  • Most of these children can be educated in mainstream schools. They should be evaluated for learning disorders
  • Children should be in the least restrictive environment possible. They should learn skills that help them be as independent as possible.
  • They should be encouraged to participate with their peers in age-appropriate activities such as clubs and teams to the best of their abilities.
  • Children should take on responsibility for their own care as much as possible.

Physioline‘s treatment programme uses a neurological approach to physiotherapy and aims:

  • To reduce spasticity and encourage more normal movements.
  • To improve motor and cognitive skills
  • To control and co-ordinate movement patterns.
  • To keep muscles strong and strengthen those are weak.
  • To keep joints mobile and prevent stiffness becoming permanent.
  • To improve co-ordination and balance.
  • To help improve gait, balance and flexibility
  • Improve aerobic activity and movement initiation
  • To improve circulation, thereby supporting bodily functions.
  • Regain functional abilities and overall independence

Occupational therapy – We give advice and help maintaining all aspects relating to activities of daily living, both at work and at home; with the aim of maintaining work and family relationships; encouraging self care where appropriate, assessing any safety issues, making cognitive assessments and arranging any appropriate interventions.

Speech and language therapy –our therapist aims at improving loudness and intelligibility of speech where possible, ensuring methods of communication are available and to help with swallowing (reducing risk of aspiration

Kindly contact Physioline for Consultation and Treatment.