Optiscan Imaging Ltd. said Peter Delaney resigned as chief technology officer.
Delaney has been with Optiscan since 1994, and will remain with the company until mid-June.
Optiscan also received two shareholder requisition notices seeking a general meeting of shareholders and calling for changes to the company's board. Optiscan said it is trying to negotiate an outcome to avoid holding such a meeting.
The Australian microscopic imaging company said the process of naming a new CEO is well advanced, with details to be disclosed in due course. Archie Fraser resigned as CEO in January.