CT Stonogram is a specific kind of Ct scan to find stones in the kidney and gallbladder.
If you haven't seen a CT Scan Machine before, it's a big machine with a hole and a bed in the middle.
Before going inside the room for the scan, you will be asked to drink a litter of water to fill up your bladder, your bladder should be full enough that you'll have an undeniable urge to pee but you have to hold it! They need your bladder full for a good scan result.
When your bladder is full and you're ready to get scanned, you'll be asked to wear a hospital gown and remove all your jewelries and metal things, if you have any metal implanted inside your body let the medical technician know.
You'll be asked to lie down the bed and the bed will be pushed in up to your waist. The medical technician will go inside the control room and will communicate with you using a microphone. You'll be asked to hold your breath for a few second as the machine scans you body, they will ask you to do that for few times till the scan is complete.
After which you'll be asked to dress up again and will be advise when you can get the result.