Lam who had appeared calm throughout the hearing of his case, shook his head after hearing the sentence while his wife and one of his daughters burst into tears. In sentencing, the judge adopted a starting point of five years but reduced it by 20 months for Lam's guilty plea, nine months in acknowledgement of his good character and six for the full restitution he had made, leaving 25 months.

'Lam was an academic of great international acclaim and he was the doyen of gastroenterology,' the judge said, also recognising Lam's research, which had had a profound effect on the treatment and prevention of duodenal ulcers and gastric cancer.

The disgraced professor pleaded guilty on Tuesday to one count of misconduct in public office. Thirty counts of fraud and three counts of theft were left on file.

The court heard earlier that Lam, a graduate of the school, had worked his way up from intern to dean. His distinguished career had earned him many awards, including an OBE for services to medicine, and he was the only person in Asia to become a Master of the American College of Gastroenterology.

In mitigation on Tuesday, Gary Plowman SC, submitted 22 letters from eminent people including former chief executive Tung Chee-hwa, doctors, professors, senior counsel and patients, who all spoke highly of Lam's character and his remarkable contribution to medicine.

Plowman said Lam's remarkable and pioneering research, including the world's first lengthy study on the effectiveness of chemoprevention in fighting gastric cancers in Fujian , had saved millions of lives.

Describing Lam as a 'conscientious and caring doctor' yesterday, Li said he had taken all these matters into account.

But he rejected Lam's claim that part of the embezzled sum was used to maintain the network his position required and that he had bent the rules to create flexibility and cover expenses he could not officially claim. He said he did not find this convincing in view of the large amount involved and found it 'disappointing' that Lam had given no further explanation about the money paid to his company.

The court heard that between September 1, 2003, and January 26, 2007, Lam induced 12 of his patients at Queen Mary Hospital to make payments totalling HK$130,000 to his company, Gastrointestinal Research. The patients had received demand notes and receipts with the university's and hospital's letterheads.

He also procured three patients to make donations of HK$3.8 million to his company and failed to disclose a conflict of interest between his roles as dean of the school and owner of the company. Bank records revealed that about HK$3 million had been transferred from Gastrointestinal Research accounts to those of Lam, his wife Lam Chan Wing-khi, and a friend.

Li said he took a 'serious view' of the fact that Lam had attempted to cover up his misconduct when the matter was first being investigated by the university. The university had been alerted to the matter after a patient who had already paid Lam, got a bill from the hospital and queried it. Lam had then tried to persuade the patient to say the first payment in December 2006 was a donation.

Leaving court, Lam's wife, faced with a media pack, said: 'I am already unhappy, please don't ask me any more questions. Excuse me.'

Outside court, one of Lam's lawyers, Keith Yeung SC, said an appeal might be discussed.