The board is urgently seeing overdue patients after delays in Dunedin and Invercargill caused 38 patients to lose part of their sight.
The department saw 140 patients in a single day last month.
Morton said administration staff were not adequately supported to cope with the numbers.
"They're working now at incredibly high capacity, with no relief, in what appears to be a crisis situation."
Yesterday, Morton still had not received a response to her June 15 letter. In a response to the Otago Daily Times, chief medical officer Nigel Millar apologised to patients "inconvenienced or distressed" by the overcrowding.
"In this instance we learned at short notice that two additional specialists were available in early June, and decided to make the most of this opportunity to ensure 140 more patients could receive the treatment they required.
"It was unfortunate the additional seating that had been ordered did not arrive in time for this clinic, and again we apologise for any discomfort this caused," Millar said.
Millar could not say how many patients were still overdue for appointments because an external review recommended changing the way they were counted.
"Once this methodology is adopted, we will provide an update of the number of patients whose appointments are overdue," Millar said.
Separately, Health Minister Jonathan Coleman's office released a progress report, written in April by senior health officials, about SDHB's ophthalmology problem.
It said two nurses were being trained to inject Avastin, a common eye procedure. Efforts to recruit optometrists to work alongside the hospital's ophthalmologists had been unsuccessful, making it difficult to clear the waiting list.
The board was considering an offer from South Canterbury District Health Board to see 10 patients a week, the report said.