I live in Adelaide Australia. A city similar in size to Aukland.
I am hearing your concerns.
Unfortunately where we live means the case loads of the surgeons in treating AN is often low.
The best surgical results are coming from a team of two surgeons. Typically a Neurosurgeon and an ENT Surgeon. This method was pioneered at House in the US and is a practice that has been copied by many in AN removals. The team of surgeons also need to have done quite a few AN surgeries before their complication rates drop. There are a number of medical papers on this.
One paper somewhere says they should have done at least 20 operations, and do at least 10 a year
The best results come from surgeons who have performed over 50 AN surgeries and do more than 20 per year.
However some surgeons still do it alone, and only do a few per year, and the results are not as good.
Its a difficult operation...
So do ask your surgeon if he works as a pair or on his own
Ask how many AN surgeries he has performed.
Ask about death rates.
I was first introduced to the world of AN after a friend 32 died after surgery for a 2cm tumour.
Death rates are around 0.5% in Australia I believe, which is similar to most modern countries.
Death rates and complications do vary a lot, between doctors.
They can be higher than 2% for some surgeons and virtually nil for others.http://www.ncbi.nlm.nih.gov/pubmed/12897555http://www.ncbi.nlm.nih.gov/pubmed/21856684
You are probably a candidate for radiation and there is a chance that your hearing can be preserved.
You may want to investigate Gamma Knife which is now available in Sydney..http://muh.org.au/health-services-australia-gamma-knife.html
Gamma Knife is now largely covered by the Australian Medicare System. Possibly the bilateral agreement between Australia and New Zealand will help reduce the cost. You may want to investigate this.
There are also higher case load surgeons in Sydney and Melbourne, or even explore going outside of Australia and New Zealand.
Due to similar concerns to yourself I ended up having my AN treated at the European Cyberknife Centre in Munich Germany. Dr Alexander Muacevic. The whole procedure took 2 hours. Mask making and planning CT scan, that was about 30 minutes. Cyberknife was 35 minutes. the rest of the time was talking with Dr Muaceveic, for as long as I wanted. Flew out of Adelaide Saturday lunchtime was back home thursday... Dr Muaceveic is currently the president of the radiosurgery society and one of the most experience radiosurgeons in the world.
The European Cyberknife centre has treated many hundreds of AN's I believe close to 1000 AN's.
Extremely happy with Dr Muacevic, and the result.
Australia did not have Gamma Knife or Cyberknife in July 2010
I believe New Zealand does not have Cyberknife or Gamma Knife.
I am also hearing about positive outcomes from the Australian Gamma Knife Centre in Sydney.
Don't be afraid to look outside New Zealand for the best outcome.
Do lots of research.
There is some really good information in the members section of the ANA website and some great insights provided by the best experts in the world at the ANA symposium. These papers are available for download in the members section.