(5) Intangible Assets

Intangible assets as of December 31, 2017 reflect the purchase price attributable to patents received in connection with the acquisition of assets of BaroFold Corp. Acquired BaroFold patents are being amortized to expense on a straight line basis at the rate of $80,000 per year over their estimated remaining useful lives of approximately 9 years. The estimated aggregate amortization expense for each of the five succeeding fiscal years is $80,000 annually. We performed a review of our intangible assets for impairment. When impairment is indicated, any excess of carrying value over fair value is recorded as a loss. An impairment analysis of intangible assets was performed as of December 31, 2017. We have concluded that there is no impairment of intangible assets. Intangible assets at December 31, 2017 and 2016 consisted of the following:

Amortization expense for each of the years ended December 31, 2017 and 2016 was $0.