Corduroy artifacts Due to defective 16 channel switch.

MRIQ Intermittent Corduroy, Cross Hatching type Artifacts See long description The original complaint was intermittent Corduroy, Cross Hatching type artifacts on multiple coils. I visited the site with the SNT tool in tow and reviewed the images and agreed that the artifact was indeed White Pixel induced Corduroy and Cross Hatching. WP failures ranged from 340 to 4000 during EPT WP test. We set up the SNT tool and within hours we had discovered several sources mainly in the Computer flooring and with exposed areas on the Cold Head lines. We were successful in remedying them which required leaving out several tiles and isolating the Cold Head lines. This is were the troubleshooting gets very interesting. After a 1000 images with no WP detected with the SNT tool we then ran the sequence using a PA 8ch HR brain coil which exhibited the original WP artifact. The first series we ran was clean and no longer exhibited the WP artifacts however we ran the series again only to discover the second series exhibited the following images with a Corduroy / Cross hatching type artifact: