In recent weeks, medical-device maker ev3 (NASDAQ:EVVV) has made some significant breakthroughs that look promising for shareholders. Its most recent quarter should have made them happy, too -- the company reported yesterday that its net sales increased 41% year over year and that 2007 net sales will top 2006 full-year results by another 29% to 37%.

Based in Plymouth, Minn., ev3 has two primary operating segments. Its cardio peripheral segment, which makes products for the treatment of coronary disease and other heart-related ailments, enjoyed a Q4 net sales increase of 42% over the previous year's comparable quarter. The company's neurovascular segment, whose products are aimed at treating vascular disease and other disorders in the brain, also had a strong showing; its net sales increased by 39% over the prior year's Q4.

Before you get too excited, though, consider the inherent risk associated with any company that has recently gone public and is still working to achieve profitability. This company, which went public in June of 2005, is definitely headed in the right direction -- its financial condition has improved dramatically. However, it still reported a loss of $4.6 million for its 2007 Q4. That's 79% better than its year-ago Q4 loss of $22 million, but it's still a loss. On the upside, ev3 expects its quarterly operating losses to shrink even further in 2007 and is expecting to generate $10 million to $15 million in EBITDA for fiscal 2007, excluding non-cash stock-based compensation.

As for the recent breakthroughs, the company last month announced FDA approval for its Protege Rx Carotid Stent, which is used in the treatment of carotid artery disease. Competition in this market has been heating up -- ev3 management estimates that the carotid stenting market could reach $250 million worldwide in 2007. Meanwhile, Cordis, a Johnson & Johnson (NYSE:JNJ) company, announced FDA approval just last week for its own new version of devices to treat clogged neck arteries.

Another key development for ev3 also occurred in January, when it was reported that the company had entered into an agreement with FoxHollow Technologies (NYSE:FOXH) to conduct a joint clinical study of FoxHollow's calcium-cutting device, The RockHawk, and ev3's SpideRX endovascular devices, which can be used in the treatment of peripheral artery disease.

Should the company achieve similar growth channels in the upcoming months, ev3 could become a stock to watch as it continues to drive itself into the black.

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Johnson & Johnson is an Income Investor recommendation.

Fool contributor Billy Fisher owns shares of Johnson & Johnson. The Fool maintains a disclosure policy.