Overview
The top of the spine presses into the skull base, causing basilar invagination. The brain stem, a dense network of nerves that links the brain to the spinal cord, is constricted and pressed as a result. The disease is generally found in infants and children.
Associated Anatomy
Brain and spinal cord
Alternate Name of Basilar Invagination
Basilar impression
Basilar Invagination Causes
Basilar invagination can be congenital or can be developed over time due to soft bones.
Congenital basilar invagination In infants can develop due to:
- Chiari malformation: An abnormality present at the skull base in which the brain tissues get pushed into the spinal cord.
- Hydrocephalus: Fluid gets filled within the deep brain cavities.
- Klippel-Feil syndrome: Abnormal fusion of neck bones, causing a webbed neck.
- Syringomyelia: Development of fluid-filled cyst in the spine.
- Osteogenesis: Fragile breakable bones
- Marfan syndrome: Weak connective tissues
Basilar invagination over time can develop due to:
- Injury, caused in an accident
- Immune or endocrine or a bone or connective tissue disorder, like, brittle bone disorder, Marfan syndrome, Rheumatoid arthritis, Rickets etc.
Basilar Invagination Symptoms
Depending upon the part of the brainstem pressed or constricted, basilar invagination can cause different symptoms, such as:
- Pain in the back of the head and the upper part of the neck.
- Weakness of neck
- Convulsions in the eyes (nystagmus)
- Improper speech
- Difficulty in swallowing
- Dizziness
- Tingling and numbness in hands and feet.
- Loss of proprioception
- Paralysis in arms and legs
- Difficulty in peeing and pooping.
- Difficulty in bending the neck.
Basilar Invagination Diagnosis and Test
Tests for basilar Invagination are done by doctors specialised in neurology, neurosurgery and orthopaedics.
Your doctor will first examine your muscles and nerves based on your symptoms. MRI is the best diagnostic test to look for abnormalities in the brain and spinal cord. X-rays and CT scans can also be performed as secondary tests for better clarity.
Basilar Invagination Treatment
A child with mild or zero symptoms of basilar invagination requires regular monitoring by the doctor.
Other symptoms can be treated by:
- Anti-inflammatory medicines
- Performing manual traction on the neck.
- Use a cervical collar or cervical-thoracic brace to support the head, neck, and upper back.
- Physical therapy
- Unstable neck position and nerve constriction require surgery. Surgery is performed through the mouth, nose or back of the neck or head.
- Halo-gravity traction: helps to get the skull and neck in a better position.
Risk Factors of Basilar Invagination
Risk factors include:
- Chiari malformation
- Rheumatoid arthritis
- Injury during a bike ride or fall or diving.
- hydrocephalus
- Rickets
Possible Complication of Basilar Invagination
Complications of basilar invagination developed in the later stage of life include hydrocephalus or syringomyelia. Both these conditions block the flow of cerebral fluid around the brain and spinal cord. Loss of proprioception (a condition where you are unable to tell your body part's position without looking) and paralysis in the arms and legs can also occur.
Basilar Invagination Prevention
Primary Prevention
Primary prevention includes:
- Watching new and recurring symptoms closely
- Not kissing follow-up appointments with doctors.
- Avoid strenuous activities as the neck is already fragile; it can be fatal otherwise.
Secondary Prevention
To avoid recurrence of the disease, do not put pressure on your skull and neck bones, especially after surgery, otherwise it could be fatal. Regularly go for imaging tests to keep check on your neck and head positioning.
Epidemiology of Basilar Invagination
Since it is a congenital disease, it is more prevalent in infants and children. However, basilar invagination caused due to injury and other diseases can occur at any age.
About 5-10% cases of basilar invagination occur in patients of cervical and rheumatoid arthritis. Both conditions cause loss of axial supporting structures in the upper cervical spine.
Expected Prognosis of Basilar Invagination
Basilar Invagination is a treatable and manageable disease. With timely detection and regular monitoring, it can be cured. Those who develop this condition as a result of injury or other diseases may require surgery, which has a high success rate. Only basilar invagination, which puts pressure on the lower brainstem, can be fatal.
Natural Progression of Basilar Invagination
Congenital basilar invagination can be treated with regular monitoring, and physical therapy or by wearing a cervical collar. However, if left untreated or signs and symptoms get ignored, it may lead to unstable neck and head positioning, which requires surgery.
Pathophysiology of Basilar Invagination
Vertebra (bone) near the upper back travels up and back toward the skull base. The bone may press the brainstem and spinal cord in this abnormal posture. Basilar invagination can be congenital (existing at birth) or acquired basilar invagination (develops because of an injury or disease).
Other Conditions & Treatments
- Absence Seizures
- Arteriovenous Malformations
- Benign brain tumor
- Brachial Neuritis
- Brain Aneurysm
- Brain Cancer
- Brain Haemorrhage
- Brain Stroke
- Brain Tumor
- Chiari Malformation
- Dementia
- Dystonia
- Epilepsy
- Essential Tremor
- Fibromuscular Dysplasia
- Headache
- Hemangioblastoma
- Hemifacial Spasm
- Hydrocephalus
- Idiopathic Dystonia
- Medulloblastoma
- Meningioma
- Migraine
- Neurofibroma
- Parkinsons Disease
- Phantom Limb
- Postherpetic Neuralgia
- Radiculitis
- Spasmodic Torticollis
- Trigeminal Neuralgia
- Tuberous Sclerosis
- Vertigo