Minimally invasive surgery for a burst appendix appears to be more successful and less costly in the long run than the traditional operation, a new study hints.

Using the gentler technique, called laparoscopy, a surgeon makes small cuts in the abdomen before inserting a tiny camera inside, then performs the operation by watching a TV monitor.

Doctors say this type of operation hurts patients less afterward than the conventional "open" method, which involves one long incision in the abdomen of up to 30 cm.

But experiments comparing the two kinds of procedure have yielded mixed outcomes, and some experts remain unconvinced that laparoscopy is worth its higher upfront cost.

The new study, in the Annals of Surgery, doesn't settle that question. But it does suggest that laparoscopy could actually save thousands of dollars for some patients, when all costs are considered.

"You really want to look at the total cost, because that's what society has to pay," says Dr Dmitry Oleynikov, who heads the Center for Advanced Surgical Technology at Nebraska Medical Center in Omaha and led the new study.

But he acknowledges that the study has major limitations. First, it looks only at academic medical centers. And second, it's not a randomized controlled trial, which means the patients being compared could be different in important ways, explaining at least part of the outcomes of the two types of surgery.