The Southern District Health Board has admitted another four cases of permanent sight deterioration in patients who waited too long for eye appointments.
The four patients are on top of 34 earlier cases of irreversible partial sight loss caused by inadequate follow-up of patients at Dunedin Hospital and Southland Hospital.
''A deterioration of visual function has occurred during the delay in follow-up appointments,'' interim chief executive Chris Fleming said in a written Official Information Act response this week.
The OIA also reveals the board has yet to get control of the eye appointment waiting list.
There are now 4944 overdue eye appointment patients in Otago and Southland, compared with 4618 on November 1 when the board admitted the problem.
There had been 29 complaints from eye patients since January. Of these, more than half (16) were at Dunedin Hospital, the OIA shows.
The OIA covers the period July to September, which was the most recent data available.
In its 2015-16 adverse events report, the board disclosed 30 cases of harm in ophthalmology, on top of four cases the previous year.
Recruitment was under way for more ophthalmology staff.
''In the interim, the service is employing ophthalmologist locums on a short-term basis.
''The first locum will undertake extra clinics in December.
''The DHB is working with a number of other locums who are expected to commence work with us early in 2017,'' Mr Fleming said.
Two of the new cases were at Dunedin Hospital, and two were at Southland Hospital.
They would be added to the external review of patient harm in ophthalmology which was under way.
''The reviewers are currently reviewing data and documentation relating to these matters. This will be followed by an on-site visit, interviews with staff and further review of clinical records,'' Mr Fleming said.
Last month, Mr Fleming explained that SDHB bosses kept quiet for a long time about the extent of the problem because they wanted to have a ''free and frank'' discussion first.
Other ophthalmology departments around New Zealand are also under strain.