CT's are fairly good and the tubing can be seen all the way from the skull. Where an ultrasound can magnify and locate tender areas very precisely in regard to surrounding tissues , organs and the tubing. It may also depend on the type of shunt you have. I know mine is impregnated with a radioactive substance making location easier by xray. I have had MRI, CT, Ultrsound and Xray to locate and trace the shunt and the surrounding tissues
As for reading it yourself, I got to say not always a good idea. Those people go through years of training on what to look for, to the laymen's eye (mine) it isn't always helpful, unless explained as to what the pictures/scans are showing. I stressed myself out bigtime with worry over a scan and report which I interpreted wrongly until it was translated appropriately. I had almost convinced myself I would be dead by the end of the month. Have someone go through the reports with you, someone with the knowledge, your doctor.
Hope it helps

Merl1n