The South Island neurosurgery governance board, established to guide the fledgling service's first three years, ceased last month.
Southern District Health Board chairman Joe Butterfield said yesterday responsibility now rested with the two boards and their neurosurgery hubs in Dunedin and Christchurch.
The disestablishment had been scheduled, and was a sign service development had gone to plan, he said.
He was also chairman of the neurosurgery governance board, after taking over from Melbourne neurosurgeon Prof Andrew Kaye, who guided it from inception for the first couple of years.
It was put in place after the two district boards could not agree on how to provide a South Island service.
There were other changes, with the recent retirement of the service's first clinical leader, Martin MacFarlane, who had initially opposed the two-site service but then implemented the decision to base neurosurgery in both centres.
Fellow Christchurch neurosurgeon Nicholas Finnis was acting clinical leader.
Mr Butterfield said tension between Christchurch and Dunedin was inevitable in a joint service.
Asked about a lack of reports about neurosurgery to Southern board meetings, Mr Butterfield said there was no reason to report about the service, as it was operational, including the fact the establishment board was being wound up.
Service implementation manager Joy Farley's role would end shortly.
Asked whether the neurosurgery board compiled a 2012-13 annual report, he suggested the Otago Daily Times contact the Ministry of Health; a ministry spokesman said yesterday it appeared no annual report had been compiled.
Dr Brian McMahon, of Dunedin, who led fundraising for a neurosurgery academic unit in Dunedin, said the unit seemed to be in good shape, and was getting on well with Christchurch.
''From what I gather ... the attitudes between the two departments are very good.''
The two had to work together to survive in a ''hard world'', he said.
Dunedin neurosurgeons Prof Dirk De Ridder, Reuben Johnson, and Ahmad Taha worked well together, Dr McMahon said.
There was no reason the clinical leader had to be based in Christchurch, although many doctors would not seek that responsibility on top of other duties, Dr McMahon said.
Concern the service could be lost from Dunedin sparked a protest rally of up to 10,000 people in August 2010 and a 55,700-signature petition.
An expert panel appointed by the Director-general of Health decided it would be provided in Christchurch and Dunedin.
