A woman with a benign brain tumour has said she feels as if she has been "left to rot" after a number of her hospital appointments were cancelled.
Samantha McKee, who attends the neurology department at Belfast's Royal Victoria Hospital, has not been able to see her consultant in 14 months.
Over 9,000 people in NI are waiting on a review appointment at the department.
Ms McKee is one of thousands of people who have received a cancellation letter from the Belfast Health Trust.
The letter informed them that their appointment with their neurology consultant has been cancelled.
From her home in Loughbrickland, she told the BBC, that she feels people have "given up on her".
"I feel some people have given up trying to help me. It's not the consultants, they are excellent - when you get to see them. The problem is I can't get to see my doctor. I feel I have been left to rot," she said.
Samantha is 36 and first began having neurological problems when she was 15 years old.
Doctors diagnosed her as having a benign tumour on her brain. While it is not cancerous, because of where it is, it is inoperable and its increasing size is causing her condition to deteriorate.
In the past two years, her vision has become affected, some days she is unable to walk and generally she lives from day to day.
"When I wake in the morning, I never know what way I am going to be," she said.
"There are good days and bad days, but despite what my condition is like I always feel frustrated about the system and the way the health service feels it can treat people."
A professional artist, Samantha is now unable to pursue her career. While she accepts that her condition will not improve, she says medication can give her a better quality of life.
However, over the past year, the Belfast Health Trust has written cancelling two review appointments.
A letter from the trust said that the clinicians and management team found the situation "very frustrating and disappointing". The letter acknowledged that it was an "unacceptable situation".
Samantha's sister Annita is her main carer. Annita said the disappointment of cancelled appointments is frustrating.
"These are appointments that her consultant says she needs - it is just soul destroying watching her deteriorate," she said.
The family believe that a cancelled appointment in November last year led to Samantha being on the wrong medication. She collapsed in January 2011 and was rushed to hospital.
Annita said the Belfast Health Trust told the family that an emergency appointment with a neurologist could take up to three months.
The family instead spent £140 and within three days got a private appointment with her own consultant.
"Of course I don't mind spending the money, but that is not the point. Clearly there is something wrong with the system and there is no real evidence that trust management are addressing the problem," she said.
At that private appointment Samantha's medication was changed.
"We were told then, that she needed to be seen again in April, that appointment has since been cancelled.
"It's just not good enough, it is a horrendous situation. You write a letter, several letters of complaint and the least you expect back is an appointment. That doesn't happen. Meanwhile her condition is deteriorating, it is just sheer neglect."
Sources within the Belfast Health Trust have told the BBC that staff are becoming increasingly frustrated with a new booking appointment system that appears to be causing more problems than it solves.
While the official line from the Belfast Health Trust is that the new system means there is a backlog of up to six weeks, the reality is many outpatients are having to wait almost a year for a review appointment.
The Regional Neurology Service at the Royal provides approximately 16,000 outpatient appointments every year.
Almost half of those appointments are for patients who need to have their case reviewed. For example to check if their condition has deteriorated or perhaps that their medication needs to be changed.
The BBC has learned that within the Belfast Health Trust 6,335 people are waiting to see their consultant for a review appointment. Within the Western Health trust 1,521 people are waiting
In the Northern Health Trust there are over 816 cases. Within the South Eastern Trust 318 and in the Southern area 224.
In a statement to the BBC, a spokesperson for the Belfast Health Trust said they could not be specific about the length of time people were having to wait.
However, sources within the trust have told the BBC that the majority of patients are having to wait for between nine and 12 months.
Dr Paul Darragh from the British Medical Association said these figures were "worrying".
"As doctors what we want to do is deliver the best possible care to our patients, delivered according to sound clinical principles and according to patient need," he said.
"It's obviously of concern to all clinicians if they feel they are unable to develop and give the service that they think their patients require and need."
Aidan Dawson from Acute Services at the Belfast Health Trust said he was "always disappointed" when a patient felt that they were not cared for properly.
"We recognise that there is an outstanding backlog of review patients to be seen in neurology. We've had discussions with the commissioner and we have agreed that we will appoint a new neurologist," he said.
"For this individual lady and her case, I would be quite happy to meet with her and respond to that. I will ring her tomorrow."
Meanwhile, in Loughbrickland, Annita and her sister said they continue to wait on a call or letter instructing them of an available appointment for Samantha.
"But even when that comes we are not confident that it will actually happen," Annita said.