(this information is provided with thanks to and care of the Cavernoma Alliance: http://www.cavernoma.org.uk/cavernoma.html)
Cavernomas are clusters of abnormal blood vessels found in the brain, spinal cord, and, rarely, in other areas of the body. There are many names for this condition:
A typical cavernoma looks somewhat like a raspberry, but it can range in size from microscopic to inches in diameter. It is made of multiple little bubbles (caverns) of various sizes, filled with blood and lined by a special layer of cells (endothelium). These cells are similar to those that line normal blood vessels, but the bubble-like structures of a cavernoma are leaky and lack the other layers of normal blood vessel wall. A cavernoma can cause seizures, stroke symptoms, haemorrhages, and headache.
Cavernomas are estimated to occur in approximately 0.5-1% of the population, or in 1 in 100-200 people. Most people start having symptoms in their 20's or 30's. Cavernomas can form later in life, so incidence rates and number of cavernomas per person are higher among adults. Generally, more than 30% of those with cavernoma eventually will develop symptoms.
For at least 20% of those with the illness, cavernoma is inheritable. This form of the illness is often associated with multiple cavernomas. While familial cavernoma can happen in any family, it occurs at a higher rate among Mexican-American families. Each child of someone with the familial form has a 50% chance of inheriting the illness. Current research indicates that at least three genes can be implicated in the hereditary form. A mutation in any one of three genes can lead to the illness.
A solitary cavernoma may be present at birth or may develop later in life. If no other family members are affected, the condition is often not inheritable and is considered sporadic. This means that children of those with sporadic cavernoma may have no greater chance of having cavernoma than anyone else in the general public.
Up to 40% of solitary cavernomas may develop in the vicinity of another vascular anomaly called a venous angioma. The venous angioma, also known as venous malformation or venous developmental anomaly, usually does not create problems unless it is associated with a cavernoma. It may make surgery more difficult; the goal is not to disturb the venous angioma while removing the cavernoma.
The cavernoma is part of a spectrum of lesions known as "angiographically occult vascular malformations" related to the fact that they are not visible on an angiogram. cavernomas cannot be seen on angiogram because they have low blood flow, i.e. blood flows through the lesion slowly. This makes cavernomas different from arteriovenous malformations which are high blood flow lesions that are visible on angiogram.
A cavernoma may have no symptoms. When symptoms are present, they often depend on the location of the cavernoma and on the strength of the cavernoma walls. Cavernomas can cause seizures. A person who suffers from seizures is said to have epilepsy.
There are many types of seizure ranging from mild absence seizures to dramatic tonic-clonic seizures. Seizures tend to worsen with age and frequency. Most cases of epilepsy are well controlled with medications. The type of seizure a person experiences depends, in part, on the location of the cavernoma. If a person has seizures and more than one cavernoma, it may be difficult to pinpoint which cavernoma is the cause of the seizures.
Cavernoma can cause neurological deficits such as weaknesses in arms or legs, vision problems, balance problems, or memory and attention problems. As with seizure, the type of deficit is associated with which part of the brain or spinal cord the cavernoma affects. Symptoms may come and go as the cavernoma changes in size with bleeding and re-absorption of blood.
Cavernomas can bleed in a number of different ways:
The risk of haemorrhage is dependent on the number of cavernomas. The higher the number, the greater the chance of one or more haemorrhages occurring sometime over a lifetime. Unfortunately, cavernomas that have bled are those that are the most likely to bleed again, particularly in the first two years after their initial bleed. It is also important to note that a haemorrhage in a cavernoma in the brain stem can be life-threatening.
Finally, those with cavernoma may experience headache. This seems to be true particularly when a lesion has oozed recently.
Cavernomas are diagnosed most often when they become symptomatic. Although cavernomas have been known since the 1930's, they have not been reliably diagnosed until the advent of the MRI (magnetic resonance imaging) in the 1980's. Previously, the illness may have been misdiagnosed as multiple sclerosis or as a seizure disorder with no known cause. The cavernomas were not visible on angiogram and were only inconsistently visible on CAT scans. An MRI scan, with and without contrast and with gradient echo sequences, read by an experienced physician remains the best means of diagnosing this illness. The MRI scan may need to be repeated to assess change in the size of a cavernoma, recent bleeding, or the appearance of new lesions.
Most cavernomas are observed for change in appearance, recent hemorrhage or clinical symptoms. Medications are available to treat seizures and headaches caused by cavernomas. Surgery is advocated for cavernomas with recent haemorrhage, those which are expanding in size, and in some cases, those which are causing seizures. Radiosurgery, by gamma knife, linear accelerator or new shaped beam techniques, is a controversial treatment that has been used on cavernomas too dangerous to reach through traditional surgery.
Cerebral cavernomas are surgically removed (resected) using a craniotomy, or opening the skull. This is usually performed under general anaesthesia, except in cases where mapping of the brain while awake is needed. Cavernomas in the spine are removed using laminectomy or unroofing of the vertebrae.
Surgery for cavernoma has been made safer using the operating microscope (microsurgery) and image guided surgical navigation (also known as computer-assisted or frameless stereotaxy) to reach the cavernoma with as little disruption to normal brain or spinal cord as possible.
Risks of any surgery, including cavernoma, include stroke, paralysis, coma or death, although these complications are rare with modern surgery performed by expert neurosurgeons. Surgery on cavernoma in the brain stem and spinal cord is more risky, but these cavernomas are more dangerous if left alone. Most patients leave the hospital within a few days and resume normal life within a few weeks of surgery. However, people with neurological deficits may require a prolonged period of rehabilitation.
While researchers continue to discover new facts about cavernoma every day, many important research questions remain.
Since receiving this diagnosis, my life has been a roller coaster. I have tried various medications, some of which has made me depressed, some exacerbating my problems with language and memory. I have left my career as a solicitor and taken a massive pay cut as a result. I have been kept waiting for appointments by the NHS and put unbelievable emotional pressure on my family, friends and Alain. However, I have learnt a lot more about my condition, about being epileptic and disabled, and about myself.
I was given two options for treating this Cavernoma. The first was to treat the Cavernoma, and the primary symptom of the epilepsy through medication. The second, to have an awake craniotomy to remove the tumour.
If I were to treat the epilepsy through medication, although I would not have to undergo the horror of brain surgery, every year there would be an accumulative risk of my having a further serious and in all likelihood disastrous haemorrhage, at 2-4% per year. Therefore, by the time I was 35 old (in 15 years time) on the basis of a cumulative 3% risk, there is a 45-50% chance that I will have a serious haemorrhage. By the time I was 60, years old statistics show that there is a 100% probability of a serious haemorrhage giving rise to death/paralysis, etc. Further, should I ever want to conceive a child, being on epileptic medication at the time of conception greatly raises the chances of the child having epilepsy (which are already increased as a result of my having epilepsy).
If I were to take the latter option, there would be a 1% chance of paralysis on my left side or death. Further, even having removed the tumour, there is still a 50% chance of my having epilepsy for the rest of my life. This is because not only the tumour is now causing the epilepsy, but the damage that has been done to the brain from the haemorrhage of 15 February 2009. BUT, there would also therefore be a 50% chance of my being completely cured of this Cavernoma and epilepsy and a 100% guarantee that the Cavernoma could not haemorrhage again.
Now that my Cavernoma has reduced in size and I have compensated for the damage done to the right side of my brain (by re-organising my articulation centres to the left side of the brain with contralateral left hemisphere activation), my surgeon has confirmed it is safe to operate should I wish.
For me, the only option is surgery. My previous job as a prison law solicitor, highly depended upon the ability to drive. As long as I have a current history of epileptic seizures (within 12 months), the DVLA will not allow me to drive. Being a lawyer unfortunately normally requires high stress situations; if I were to ever hope to return to this role, I would probably find myself returning to stressful environments. Indeed, I enjoy to work under stress.
So, my surgery is to take place on 19 November 2009 at the National Hospital for Neurology and Neurosurgery in St Ann’s Square (near Russell Square), London. Mr McEvoy is my surgeon. I will undergo an awake craniotomy.
An awake craniotomy is an amazing procedure, which seems almost unbelievable at first thought. My head will be shaved (of course!) and an incision is made into the scalp. The scalp is pulled away from the scull and the temporalis muscle retracted to expose the skull. Two or three drill holes are made into the skull to allow for specialized equipment to ‘join these’ holes and remove a section of the skull. I will be anaesthetized throughout this part of the surgery and unconscious until this point. I will then be awakened and the surgeon will pass eltromagnetic currents through various parts of the brain to ensure that they have properly mapped the functioning parts of my brain before the start to enter the brain to remove the Cavernoma.
Because my Cavernoma is so deep in the brain, they will have to use microscope surgery to locate and remove the Caevernoma. My skull will then be reattached using metal screws, my scalp stapled back onto my head, and I will be moved to intensive care to recover. A biopsy of the Cavernoma will be carried out to check that it is indeed a Cavernoma and I then get to keep the remainder of the little blighter! (see the raffle presents on the event page!!)
I will remain in hospital for 7 days before being released. All being well, I will be able to walk out of the hospital… I will remain on medication for a further two years before testing whether I no longer suffer from epilepsy.