Saturday, May 02, 2009

What IS NF2?

NF2 is the shortened name for the genetic disorder know as Neurofibromatosis Type II.

NF2 causes tumors to grow on cranial nerves in the brain and nerves within the spine. Tumors may also grow on nerves elsewhere in the body.

Due to the lack of the supressor gene Merlin, there is an overgrowth of the nerve sheath cells lining the nerves, brain, and spine. These cells are known as schwann cells and the tumors may also arise from the meninges (covering of the brain).

NF2 is not contagious nor something you can "catch". People with NF2 have had the disorder since birth. After conception when the cells are forming an embryo, the disorder is either inherited from a parent with NF2 or for an unknown reason, a spontaneous mutation occurs to the merlin protein needed to stop the cell replication process of the nerves.

Who Does It Affect?

50% of those with NF2 have inherited the gene and 50% are a spontaneous mutation.
(Which am I? Apparently, my mutation did not give me super human strength or the ability to climb walls! hehe)

New studies indicate that 1 in 25,000 people have NF2.

NF2 affects both sexes, all ethnicities, all around the world.

Generally, as the tumors grow, symptoms begin to manifest during the late teens to early adulthood (20s). However, there are cases of people being diagnosed later in life as well as younger children. With new testing and familiarity with the nature of NF2, I am seeing more children being diagnosed at earlier ages (3,5,7).

What Problems Does It Cause?

The most common manifestation of NF2 is hearing loss or total deafness caused by tumors growing on both auditory nerves (8th cranial nerves). These tumors are know as vestibular schawnnomas and they are the "hallmark" of NF2. ALL with NF2 eventually experience hearing loss.

90% of people with NF2 experience vision impairment due to ocular abnomalties, ocular tumors, tumor or brainstem compression, or facial paralysis. Such results in lack of tear production, inability to close the eye, inability to open the eye, blurred or double vision, or loss of vision entirely.

50% of those with NF2 have spinal tumors which cause pain or some sort of disturbance to normal function.

A common struggle among people with NF2 is the loss of balance function making it difficult to do simple tasks such descending stairs or trying to put on underwear while standing. Often those with balance dysfuntion have an awkward gait and stagger around like a drunk. A few of us have been confronted by law enforcement officers accusing us of being under the influence of a substance or drink. Some use a cane or need a wheelchair to get around.

Also common among many is muscular atrophy or "muscle wasting". At one point before I began a regular regimen of strength training (lifting weights at a gym), I could not carry around a simple shopping basket without falling over and it quickly became too heavy to carry.

Other side effects which have resulted from complications of the tumors or treatment: facial paralysis, muscle weakness and loss of coordination in the hands, a condition known as "drop foot", facial pain or pain in the extremeties known as neuralgia, numbness in the hands, feet, legs, and face, tooth decay from lack of saliva production "dry mouth", swallowing or eating difficulties, chronic body pain, mental cognition difficulties, on rare occassion cancer, and in many case early morbidity (shortened life span).

Please visit our memorial page in memory of our young friends who have lost their lives to NF2: In Memory of Friends Lost to NF2

The Difficulty in treating NF2 - No Cure

As compared to brain tumors known as acoustic neuromas which are much more common in the general population, vestibular schwannomas grow faster and more aggressively.

Schwannomas infilterate the nerves making them surgically difficult to remove without causing permanant damage to the nerves and other critical atructures such as the brainstem.

The tumors that tend to be less uniform in shape having a nodular and bumpy composition or with tentacles, make both surgery and radiosurgery more complicated.

Even after radiosurgery and surgery, the tumors often grow back.

References

http://www.dinagoldin.com/anarchive/nf2.htm

http://www.theuniversityhospital.com/nf/aboutnf2.htm

http://www.advocurenf2.org/01_understandingnf2.html

http://www.nf2crew.org/

http://ghr.nlm.nih.gov/gene=nf2

http://www.genecards.org/cgi-bin/carddisp.pl?gene=nf2

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