Statements of Operations (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenue:
Systems Revenue	$ 5,024,543	$ 9,439,857	$ 9,312,719	$ 14,673,611
Recurring Revenue	6,577,596	5,578,221	12,514,124	10,961,076
Total revenue	11,602,139	15,018,078	21,826,843	25,634,687
Cost of revenue:
Systems Cost of Goods Sold	2,520,431	4,313,774	4,704,909	6,390,490
Disposables Service and Accessories Cost of Goods Sold	995,915	612,379	1,816,416	1,456,332
Total cost of revenue	3,516,346	4,926,153	6,521,325	7,846,822
Gross margin	8,085,793	10,091,925	15,305,518	17,787,865
Operating expenses:
Research and development	3,311,177	3,358,008	6,705,436	6,727,546
Sales and marketing	9,712,519	8,446,612	18,050,855	15,141,730
General and administrative	4,606,555	3,976,057	8,856,824	7,866,394
Total operating expenses	17,630,251	15,780,677	33,613,115	29,735,670
Operating loss	(9,544,458)	(5,688,752)	(18,307,597)	(11,947,805)
Other income	620,409	2,507,221	640,755	970,052
Interest income	2,133	2,148	5,320	4,930
Interest expense	(772,769)	(682,804)	(1,583,096)	(1,315,921)
Net loss	$ (9,694,685)	$ (3,862,187)	$ (19,244,618)	$ (12,288,744)
Net loss per common share:
Basic and diluted	$ (0.18)	$ (0.08)	$ (0.35)	$ (0.25)
Weighted average shares used in computing net loss per common share:
Basic and diluted	54,780,872	49,885,589	54,750,443	49,753,046