Leeds-based Ultralase said it would not affect trading and vowed to power ahead with growth plans with new funds released by backers.

In the restructuring, Ultralase placed one of its holding companies, Ultralase Finance, into administration and sold it the same day to a new vehicle called CLVC Group, which is backed by the private equity arms of its senior debt lenders, Barclays, Royal Bank of Scotland, Lloyds and Bank of Ireland.

Jon Hughes, the commercial director, said: "The trading companies are completely unaffected. They continue to operate and continue to do very well. Business is significantly up on last year and they continue to make profits."

Following the restructuring, the group's trading companies will feed into Ultralase Acquisitions, which is majority owned by CLVC Group, with management holding a minority stake.

Mr Hughes would not discuss the size of the banks' shareholding or the current valuation of the group. Ultralase's annual accounts for 2009 are overdue but are expected to show turnover of between £40m to £50m.

Mr Hughes said: "The key thing is, now we have the restructuring out of the way, we have funds available to continue to grow the business. We have capital funds committed as part of the new deal."

Ultralase is commencing a training project for all employees and is hoping to capitalise on emerging technologies to treat presbyopia, a condition which affects the eye's ability to focus.

The company is hoping to expand its coverage of the UK and plans to open new consulting rooms and clinics.

In a statement, Tony Veverka, the chief executive, said: "2009 was a significant year for Ultralase and one which has helped us set firm foundations for future growth. While navigating through the economic crisis, we have successfully expanded our operation into Ireland and launched new treatment types across all clinics."

KPMG, which acted as administrator to Ultralase Finance, said: "Ultralase was bought at the top of the market. As the market came down the banks became economic owners of the business."

A spokeswoman for 3i said: "We had already written down the value of the business so it is held at nil value on our books. Therefore it is an unrealised loss for us."