A list of normal radiological reference values is as follows:
adrenal gland: <1 cm thick, 4-6 cm length
abdominal aorta: <3 cm diameter
appendix: on CT <6 mm caliber
atlantodental distance
adults: <3 mm
children: <5 mm
azygos vein: on erect chest x-ray <10 mm diameter
bladder wall: <3 mm...