Wednesday, 25 March 2009

Week 2 ...... so it's a meningioma, now what?

Well it has been quite a roller-coaster ride this week .... from that first telephone call to the neurology appointment. After the GP's phone call I was quite calm and controlled, but possibly due to shock rather than bravery! Facing a very busy week, which included friends staying for three nights, I found myself behaving like a normal, rational human being! At first, that is.

Who to tell?
After discussing it with John I decided that I would just tell the few friends that knew I'd been sent for a CT Scan. I did not want the whole world to know. It seemed to be courting a bad outcome somehow to tell people when I did not know the full extent of the problem ..... Superstitious? You bet!

The major question was when to tell my children in UK? My daughter here in Dunedin was fully aware and with me every step, but I felt it perhaps better to wait until I had full details before worrying the rest of the family. However, my daughter felt that they should know a.s.a.p. and contact was made. My phone and mobile subsequently became red hot (!) but it was good to know that they were concerned and supporting me.

As I've said the first few days seemed calm, if surreal, but towards the end of the first week I became increasingly stressed and tearful. Any kind word and the 'waterworks' started! I seemed to go from 'in control' to defenseless in one fell swoop.

Yesterday, 7 weeks + one day since my GP wrote the referral letter, I went for my neurology appointment at Dunedin hospital. The neurologist was very good - calm, quiet but very approachable and easy to talk to.

What/How big is it? - First up he showed me CT images of my tumour and explained them. He is confident that the tumour is a benign meningioma and its size is currently small at 2cm x 1.7cm x 1cm. There is no way of knowing how long it has been there or what its rate of growth is, but meningiomas are usually very slow growing.

Where is it? - Unfortunately this one is in rather an inaccessible place. It is positioned at the base of the skull and lies in close proximity to the brain stem (medulla oblongata). The vomiting centre is in the brain stem so that explains the nausea! Anyway a decision must be made as to what do about it as there is no 'spare room' down there and the brain stem contains the vital centres for breathing heart, etc (!). It is also where all the sensory and motor nerves pathways are between brain and spinal chord.

Posterior fossa meningiomas (10%)

Posterior fossa meningiomas lie on the underside of the cerebrum within the posterior cranial fossa. The posterior fossa is the deepest, most capacious and anatomically complex of the three cranial fossae, it houses the brainstem and the cerebellum. The brainstem contains all the cranial nerve nuclei and many efferent and afferent fiber tracts that connect the brain with the rest of the body. The cerebellum is the major organ of coordination for all motor functions and mental activities. Located centrally in the posterior fossa is the foramen magnum which is the large opening at the base of the skull through which the spinal cord becomes continuous with the medulla oblongata (part of the brainstem).

Posterior fossa meningiomas include tentorial, clival, cerebellopontine angle and foramen magnum meningiomas. Tentorial meningiomas are those located under the surface of the tentorium cerebelli. Clival meningiomas proceed from the clivus bone in the direction of the middle cranial fossa or the direction of the brainstem. Cerebellopontine angle lesions arise from the medial portion of the petrous bone. Foramen magnum meningiomas arise at or near the anterior rim of the foramen and cause spinal cord compression.

Tumors that arise in the posterior fossa are considered some of the most critical brain lesions due to the limited space in which they can grow and the potential involvement of critical neural structures. For instance they may cause facial symptoms or loss of hearing via compressing either the seventh (facial) or the eighth (acoustic) cranial nerves, respectively. They can compress the brainstem causing clinical manifestations of brain stem compression like cranial nerve deficits, or the cerebellum causing troubles with walking and balance, or the spinal cord causing motor or sensory deficits. Meningiomas in this region can also cause blockage of the flow of the cerebrospinal fluid (CSF), or hydrocephalus, causing the intracranial pressure to rise which usually manifests by headache, blurring of vision, nausea or vomiting.

What are they going to do? - first there will be a case conference to decide the best way of managing my tumour. The decision will be made through discussion between the neurologist, the neurosurgeon and the radiologist:

Waiting and watching is not an option now that I am getting symptoms.

It seems very unlikely that surgery will be attempted because of the difficulty of access and the risk to vital centres.

The most likely course of action will be radio-surgery using the Gamma knife machine. Dunedin has the ONLY hospital offering this special facility in the whole of New Zealand .... how about that for luck! ( 9/4/2009 EDITING to say I think I am wrong about this ..... Dunedin offers cyber-knife surgery but I'm not sure about the Gamma-knife ..... they are different and I will write about the two types of treatment at a later date)