Anatomy of an AVM
Blood comes from healthy arteries and drains into the venous system, bypassing the normal capillary network.
Natural history of AVMs
Over time, the angioarchitecture of an AVM may change:
- Increase in size
- Development of arterial aneurysms
- Seizures
- Bleeding — the spontaneous risk is estimated at 2 to 4% per year, and is higher when the AVM has already bled and has not been treated
Spetzler-Martin classification
AVMs are classified according to their location, size, and venous drainage (superficial or deep).
- Grades I and II — often curable
- Grade III — treatment is possible but with a higher risk of complications
- Grades IV and V — complex forms for which the risk of complete treatment is generally too high. Selective treatment of the area responsible for the bleeding is sometimes possible.
Research may offer new alternatives, notably through targeted therapies.
Diagnosis and management
When an AVM is discovered incidentally on an MRI or CT scan, an additional angiographic assessment may be proposed. The management strategy is then discussed in a multidisciplinary meeting by the vascular team.
In the event of bleeding, treatment is generally considered promptly due to the risk of recurrence, depending on feasibility.
Therapeutic options
The choice depends on the characteristics of the AVM and the patient’s condition:
- Endovascular
- Surgical
- Radiotherapy
- Combined surgical and endovascular
- Combined endovascular and radiotherapy
- Combined endovascular, surgical, and radiotherapy
What vascular malformations have in common is that they can manifest themselves suddenly as haemorrhage:
- haemorrhage around the brain in the subarachnoid spaces called subarachnoid haemorrhage or meningeal haemorrhage
- cerebral hemorrhage or cerebellar hemorrhage in the brain or cerebellum
- cerebro-meningeal hemorrhage when the hemorrhage is both in the sub-arachnoid spaces and in the brain.
These vascular malformations may also be discovered incidentally during a CT or MRI scan performed to look for something else.
Finally, they can manifest as epilepsy.
Early diagnosis and multidisciplinary management is the key to effective treatment of these tumors.
Because of their location, injuries to the base of the skull can cause a wide range of symptoms, including visual, hearing, smell, balance and swallowing disorders, headaches, facial asymmetry, sensitivity disorders and/or facial pain, nasal obstruction, vertigo...
Cerebral CT andMRI scans are the main tests used to identify the lesion. CT scans enable precise assessment of bone structures, but lack spatial resolution for soft tissues. MRI enables precise assessment of the soft tissues, the lesion and its relationship with surrounding structures. Other tests may be ordered depending on the type and location of the suspected lesion:
- cerebral angioscan, MRI angiography and/or arteriography to assess the vascularity of the lesion, its relationship with the major vessels supplying the brain, such as the internal carotid and vertebral arteries, and the anatomy of the cerebral drainage veins, in order to preserve them as much as possible,
- an ophthalmological check-up
-an ENT check-up to assess hearing, balance and swallowing skills
-an endocrinological check-up to assess any possible repercussions of the lesion on the functioning of the pituitary gland, a small gland connected to the brain and located at the center of the skull base
etc...
Guide
Your stay is our priority, and we have established a patient pathway program for your surgical schedule, admission and intervention, through to your discharge. Please do not hesitate to contact us if you have any questions.