Volcano (VOLC) erupted Monday, rising 3% in furious trading.
The move comes just two days before the Rancho Cordova, Calif., maker of intravascular ultrasound gear is due to present at the 2007 Bank of America Health Care Conference.
CEO Scott Huennekens is due to speak at 2:20 p.m. EDT Wednesday.
Shares rose 62 cents to $21.25 on late morning volume of 1.1 million shares -- three times the full-day daily average over the last three months, according to Yahoo! Finance.