Reverse Stock Split, Policy [Policy Text Block]

Reverse Stock Split - December 2020

The Company effected a 1-for-10 reverse stock split of its common stock that became effective after market close on December 1, 2020. The reverse stock split uniformly affected all issued and outstanding shares of the Company’s common stock. The reverse stock split provided that every ten shares of the Company’s issued and outstanding common stock was automatically combined into one issued and outstanding share of common stock, without any change in par value per share. The number of authorized shares of common stock remained at 75,000,000 shares.

As a result of the reverse stock split, proportionate adjustments were made to the per share exercise price and/or the number of shares issuable upon the exercise or vesting of all then outstanding stock options, deferred restricted stock awards and warrants, which will result in a proportional decrease in the number of shares of the Company’s common stock reserved for issuance upon exercise or vesting of such stock options, deferred restricted stock awards and warrants, and, in the case of stock options and warrants, a proportional increase in the exercise price of all such stock options and warrants. In addition, the number of shares reserved for issuance under the Company’s equity compensation plans immediately prior to the effective date will be reduced proportionately. The Company issued 5,931 shares of common stock as a result of this adjustment.

No fractional shares were issued as a result of the reverse stock split. Stockholders of record who would otherwise have been entitled to receive a fractional share were rounded up to the nearest whole number.

All of the share numbers, share prices, and exercise prices have been adjusted, on a retroactive basis, to reflect this 1-for-10 reverse stock split.

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash and Cash Equivalents

The Company considers all highly liquid investments purchased with an original maturity of three months or less, at the time of purchase, to be cash equivalents. The Company’s cash and cash equivalents are deposited in demand accounts primarily at one financial institution. Deposits in this institution may, from time to time, exceed the federally insured amounts.

Receivables, Trade and Other Accounts Receivable, Allowance for Doubtful Accounts, Policy [Policy Text Block]

Accounts Receivable and Allowance for Doubtful Accounts

Accounts receivable are recorded at the invoiced amount and are not interest bearing. Our typical payment terms vary by region and type of customer (distributor or physician). Occasionally, payment terms of up to six months may be granted to customers with an established history of collections without concessions. Should we grant payment terms greater than six months or terms that are not in accordance with established history for similar arrangements, revenue would be recognized as payments become due and payable assuming all other criteria for revenue recognition have been met. The Company maintains an allowance for doubtful accounts for estimated losses resulting from the inability of its customers to make required payments. The Company makes ongoing assumptions relating to the collectability of its accounts receivable in its calculation of the allowance for doubtful accounts. In determining the amount of the allowance, the Company makes judgments about the creditworthiness of customers based on ongoing credit evaluations and assesses current economic trends affecting its customers that might impact the level of credit losses in the future and result in different rates of bad debts than previously seen. The Company also considers its historical level of credit losses. The allowance for doubtful accounts was $49,000 as of September 30, 2021 and $124,000 as of December 31, 2020.

During the three month and nine months ended September 30, 2021, the Company wrote-off accounts receivable totaling approximately $115,000 and $179,000, respectively, primarily related to U.S. customers. There were no write-offs of customers’ accounts receivable during the three months ended September 30, 2020. During the nine months ended September 30, 2020, the Company wrote-off accounts receivable totaling approximately $173,000 primarily related to Latin America distributors in connection with the Company’s shift in its international business model and the withdrawal from certain countries in Latin America.

Equity Method Investments [Policy Text Block]

Investments in Unconsolidated Affiliates

The Company uses the equity method to account for its investments in entities that it does not control but have the ability to exercise significant influence over the investee. Equity method investments are recorded at original cost and adjusted periodically to recognize (1) the proportionate share of the investees’ net income or losses after the date of investment, (2) additional contributions made and dividends or distributions received, and (3) impairment losses resulting from adjustments to net realizable value. The Company eliminates all intercompany transactions in accounting for equity method investments. The Company records the proportionate share of the investees’ net income or losses in equity in earnings of unconsolidated affiliates on the condensed consolidated statements of operations. The Company utilizes a three-month lag in reporting equity income from its investments, adjusted for known amounts and events, when the investee’s financial information is not available timely or when the investee’s reporting period differs from our reporting period.

The Company assesses the potential impairment of the equity method investments when indicators such as a history of operating losses, a negative earnings and cash flow outlook, and the financial condition and prospects for the investee’s business segment might indicate a loss in value. The carrying value of the investments is reviewed annually for changes in circumstances or the occurrence of events that suggest the investment may not be recoverable. No impairment charges have been recorded in the condensed consolidated statements of operations during the three and nine months ended September 30, 2021 and 2020.

Share-based Payment Arrangement [Policy Text Block]

Accounting for Stock-Based Compensation

Share-based compensation cost is measured at grant date, based on the fair value of the award, and is recognized as expense over the employee’s service period. The Company recognizes compensation expense on a straight-line basis over the requisite service period of the award.

The Company determined that the Black-Scholes option pricing model is the most appropriate method for determining the estimated fair value for stock options and purchase rights under the employee stock purchase plan. The Black-Scholes option pricing model requires the use of highly subjective and complex assumptions which determine the fair value of share-based awards, including the option’s expected term and the price volatility of the underlying stock.

Equity instruments issued to nonemployees are recorded in the same manner as similar instruments issued to employees.

Earnings Per Share, Policy [Policy Text Block]

Net Loss per Share

The Company’s basic net loss per share is calculated by dividing the net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period. The diluted net loss per share is computed by giving effect to all potentially dilutive common stock equivalents outstanding during the period. For purposes of this calculation, stock options and warrants to purchase common stock and restricted common stock awards are considered common stock equivalents. For periods in which the Company has reported net losses, diluted net loss per share is the same as basic net loss per share since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.

The following securities were excluded from the calculation of net loss per share because the inclusion would be anti-dilutive:

		Nine Months Ended
		September 30,
		2021		2020

Convertible preferred stock:
Series A convertible preferred stock	(a)		-		-
Series B convertible preferred stock	(b)		2,567,255		2,270,261
Series C convertible preferred stock	(c)		-		-
Warrants to purchase common stock			9,793,599		1,771,088
Stock options to purchase common stock			3,195,742		975,605
Deferred restricted common stock units			679,000		-
Deferred restricted common stock awards			228		234

(a)

Each share of Series A convertible preferred stock was convertible at any time at the holder's option into one share of common stock. As of September 30, 2020, all Series A convertible preferred stock had been converted into common stock and there were no remaining shares outstanding. In December 2020, the Company filed a Certificate of Elimination with the Delaware Secretary of State with respect to the authorized shares of Series A convertible preferred stock.

(b)

As of September 30, 2021 and 2020, a total of 39,279 and 34,735 shares of Series B convertible preferred stock were outstanding and convertible into 2,567,255 and 2,270,261 shares of common stock, respectively. Each share of Series B convertible preferred stock is convertible at the holder's option into shares of common stock at a conversion ratio of 1-for-65.36 per share determined by dividing the Series B liquidation amount of $1,000 per share by the Series B conversion price of $15.30 per share. However, under the terms of the Series B Preferred Stock and Warrant Purchase Agreement, as amended, CRG will not convert the Series B preferred stock or exercise the CRG warrants until the Company’s stockholders act to authorize additional number of shares of common stock sufficient to cover the conversion shares.

(c)

Each share of Series C preferred stock is convertible at any time at the holder's option into one share of common stock. As of September 30, 2021, all Series C convertible preferred stock had been converted into common stock and there are no remaining shares of Series C convertible preferred stock outstanding.