THE HSE is set to review the involvement of the master of the National Maternity Hospital, Dr Rhona Mahony, and four consultant colleagues in a private clinic.
HSE chief Tony O'Brien said he would examine whether the nearby Merrion Fetal Health clinic, which provides ultrasounds, represents a conflict of interest for the doctors, who are partners in the operation.
Mr O'Brien was replying to queries from members of the Dail Committee on Public Accounts in the wake of an audit showing voluntary hospitals and agencies funded by the HSE were flouting pay rules by awarding salary top-ups.
Mr O'Brien told committee members funding had been cut for a disability organisation, the Cope Foundation in Cork, which was paying a publicly funded top-up of nearly €25,000 to its chief executive.
While other hospitals and agencies are now facing the same punishment, Mr O'Brien said the HSE was worried about hurting patients.
"We'll have to find ways of doing it (penalising) without diminution in service," he added.
Dr Mahony was among the senior managers listed in a HSE audit as getting a €45,000 privately-funded allowance. She has insisted that the money comes from private patients.
Questioned on how the allowance was termed "privately-funded", HSE auditor Geraldine Smith said this was how it was described in the information she received from the National Maternity Hospital.
She was "further assured" by the hospital, which said it was validated by its chairman, Archbishop Diarmuid Martin.
"It clearly states that there are four privately-funded allowances paid," she added.
And when questioned on the sources of funding, she was told it came from "rents, licence fees and other incomes". The hospital made no mention of payments from private patients.
Separately, the board of Crumlin Childen's Hospital has acknowledged the concern that the top-ups controversy has caused children, parents, staff and supporters of the hospital.
It previously emerged that Lorcan Birthistle, the chief executive of the hospital, is paid a €30,000 top-up from the proceeds of its shop and on-site commercial activity.
A statement said: "The hospital has fully engaged with the HSE and has confirmed that the remuneration of the chief executive includes an allowance funded from on-site commercial activities."
It reiterated that no charitable donations had been used to pay this allowance.
And it said that the board previously attempted to secure approval of the health authorities for an appropriate level for the chief executive. The board believes this can now be achieved in accordance with HSE recommendations and it will pursue this with the HSE.