Lehman’s troubles are spreading not only through its headquarters in Midtown Manhattan, but through the surrounding streets.

From the nearby gyro cart to the glitzy bar a stone’s throw from the bank, many others are feeling the ripple effect.

At Tonic Restaurant & Bar, business has taken a significant hit since the end of February, said Joseph Jacobino, its marketing and sales director. Before February, Lehman had two to three corporate events at the midtown bar each week, Jacobino said.

“They scaled back dramatically — to none,” he said. “It was a significant loss to us.”

Even those insiders who have managed to cling to their jobs walked in and out of the building on Thursday looking worried and avoiding eye contact.

“These are tough, tough times,” said a Lehman staffer in its IT unit, as he bought coffee. As the bank’s stock value withers, he was thankful for being a relatively new employee because he has far less invested in the stock than more senior colleagues.

“Scary,” he said. “There are people inside who have been here for years. I’ve just been here one year.”

For those who got axed in Lehman’s latest round of job cuts, it was drinks one last time at Tonic on Wednesday, said the bar’s manager, who requested anonymity.”It was depressing. A group of guys … they were saying goodbye to each other, about 40 of them,” he said.

Bartender Alison Ryan worried about what that would mean after the toasting and cheering die out and traffic dries up.

“That’s good short term, but bad in the long run,” she said.

(Photo: Lehman staff standing in a meeting room at Lehman Brothers’ offices in the financial district of Canary Wharf in London on Sept. 11, 2008. Lehman wouldn’t tell us what was going on in the photo.)