The head of a health trust which treats neurosurgery patients from north Wales says she wants to be involved in talks on the future of the service.
Plans to close the neurosugery unit in Swansea were put on hold in July
Mel Pickup, of the Walton Centre in Liverpool, was "surprised" to hear of plans that could see patients sent to Cardiff or Swansea for planned surgery.
Her comments follow a meeting with David Jones, MP for Clwyd West, who described the plans as "ridiculous".
The Welsh Assembly Government said no decision has yet been made.
In Wales, adult neurosurgery, which treats disorders of the nervous system including diseases of the head, brain and spine, is performed at Cardiff and Swansea.
But patients from north Wales currently travel across the border to The Walton Centre for Neurology and Neurosurgery.
Chief executive Mel Pickup told BBC Wales she has written to Welsh Health Minister Edwina Hart after learning about possible changes to the service.
She said she understood some of the motivations behind possible changes but wanted to be included in any talks.
She said: "We would like very much to be involved in some of the discussions around how that best might happen for the people that we are currently providing those services for."
Conservative MP David Jones said north Wales-based patients were used to being treated in centres of excellence in Liverpool and Manchester, rather than Cardiff and Swansea, which could add more than three hours to journey times each way.
Of the Walton Centre, he said: "This place is convenient, I'm sure it's cost effective, it's a state-of-the-art hospital and this is where north Wales patients should be treated."
He said continuity of care for neurology patients in north Wales was also of "vital importance".
It was following a Health Commission Wales report in 2006 that proposals to create a single service in Cardiff were announced and led to a campaign against the plans.
In July, Ms Hart announced she would keep the neurosugery unit in Swansea's Morriston Hospital open because she wanted a fresh approach.
She said she wanted to ensure as many non-emergency operations as possible were carried out in Swansea and Cardiff and warned Wales could lose part of its service unless best use was made of it.
But concern for how the changes would affect patients in north Wales mounted and in July, Conservative Clwyd West AM Darren Millar called it "totally unacceptable" to expect patients to make what could be a 400-mile round trip.
Earlier this month, it was understood that Labour Wrexham MP Ian Lucas wrote to Ms Hart expressing the concerns of a group of north Wales MPs.
Labour Clwyd South AM Karen Sinclair said her constituents were currently "very very well served by Walton" and said the move was unacceptable and unsustainable.
The Welsh Assembly Government said no decision had been made on the future provision of neurosurgery services in north Wales.
Suggesting such a decision had been made, it added, would be "scaremongering".