CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS
Revenues, net	$ 24	$ 17	$ 42	$ 36
Cost of goods sold	13	9	20	20
Gross margin	11	8	22	16
Operating expenses:
Research and development	2,730	2,413	5,057	5,354
Sales and marketing	566	586	1,167	1,383
General and administrative	1,182	1,280	2,628	2,583
Total operating expenses	4,478	4,279	8,852	9,320
Loss from operations	(4,467)	(4,271)	(8,830)	(9,304)
Change in fair value of warrant liability	23	525	(43)	161
Other income, net	34	5	63	6
Loss before provision for income taxes	(4,410)	(3,741)	(8,810)	(9,137)
Provision for income taxes			2	1
Net loss and comprehensive loss	$ (4,410)	$ (3,741)	$ (8,812)	$ (9,138)
Basic and diluted net loss per share	$ (0.02)	$ (0.05)	$ (0.05)	$ (0.13)
Shares used in computing basic and diluted net loss per share	191,325,000	74,357,000	185,616,000	71,069,000