OSI Systems Inc. on Wednesday said its fiscal fourth quarter net income rose 28 percent on higher sales of its airport security and medical monitoring systems.

While the quarter’s profits fell short of analysts’ estimates, the company’s guidance for the coming year was in line with expectations.

The Hawthorne company reported net income for the quarter ended June 30 of $5.5 million, or 31 cents a share, compared to net income of $4.3 million (24 cents) in the same period a year ago. Revenues grew 12 percent to $171 million, a record for the quarter and 6 percent higher than the consensus of analysts surveyed by Thomson First Call.

But excluding one-time items such as impairment, restructuring and other charges related to an earlier acquisition, OSI’s net income was 36 cents a share, 2 cents less than the consensus.

OSI Systems Inc. makes an airport security screening system that it is marketing to the federal government, and that smaller division reported a 21 percent revenue growth and a 104 percent improvement in operating income, said Chief Executive Deepak Chopra.

For the full fiscal year, OSI swung to a profit of $13.9 million (78 cents) from a loss of $18.8 million (-$1.12) in fiscal 2007. Annual revenue climbed 17 percent to $623 million. Results were helped by a $4.3 million tax benefit associated with the repurchase of a minority stake in Spacelabs Healthcare.

“Our performance in fiscal 2008 marked the beginning of a significant financial turnaround to improve earnings and cash flow,” said Chief Financial Officer Alan Edrick in a statement.

OSI shares were down 43 cents, or 2 percent, to $22.98 in morning trading on the Nasdaq.