Around 100 people attended a meeting in Colwyn Bay, Conwy on Friday to protest against possible changes to neurosurgery services.
Neurosurgery services in north Wales were discussed
A review of services is currently under way and patients in north Wales fear they may be told to travel to south Wales rather than Liverpool.
Health Minister Edwina Hart has told north Wales AMs that no patient will be "forced" to make long journeys.
She said no decision had been made on moving north Wales neurology services.
In Wales, adult neurosurgery is carried out in both Cardiff and Swansea, but patients from north Wales travel to the Walton Centre for Neurology and Neurosurgery in Liverpool for treatment.
Conservative MP for Clwyd West David Jones, who called the meeting, said about 600 in-patients from north Wales were treated there each year, as well as a larger number of out-patients.
Maldwyn Jones from Caernarfon, Gwynedd, said his adult son David regularly travels to Merseyside for treatment, and he would never make the journey to south Wales because it was too long.
"Can you imagine going down to a hospital and having an appointment at nine o'clock or 9.30 in the morning. This would mean we would have to leave Caernarfon at four o'clock in the morning," he said.
Concerns were also raised at the meeting on the effect removing elective neurosurgery from Walton hospital might have on other services.
Dr Mark Doran, a consultant neurologist at Walton, who also sees patients at hospitals in north Wales, said any possible move would result in difficulties co-ordinating treatment and continuing care for patients.
Ms Hart did not attend the meeting and on Friday accused opposition politicians of "scaremongering".
An independent review of how the two neurosurgery centres in Cardiff and Swansea could be maintained was announced by her in July.
Edwina Hart accused politicians of "scaremongering".
She also wanted the review to consider the possibility of all adult Welsh patients receiving non-urgent or planned neurosurgery to be treated in south Wales.
In 2006, plans to create a single service in Cardiff were announced after a Health Commission Wales report.
It recommended the service be centralised in Cardiff, but Ms Hart put controversial plans to shut the specialist unit in Swansea on hold in July after a high-profile campaign.
At the time, Aberconwy Plaid Cymru AM Gareth Jones suggested a location like Llandudno would be ideally suited for patients in north Wales as an alternative to having two specialist centres in south Wales.
But Ms Hart has said she wanted to make sure as many non-emergency operations as possible were done in Cardiff and Swansea, warning that Wales could lose part of its service unless best use was made of it.
A panel which will look at a scheme to pay patients' travel costs is due to report back in October.
The assembly government said Ms Hart had written to Mr Jones to tell him that she would not be at the meeting.
"The minister does recognise the strength of feeling over neurosurgery," said a statement.
"But let's be clear, no decision has been made on the future provision of neurosurgery services in north Wales.
"Any suggestion that there has been, would be pure scaremongering. Arrangements stand as they currently are."
"An independent review into the future of neurosurgery in Wales is being set up and is to be chaired by Mr James Steers, a consultant neurosurgeon based in Edinburgh."