Table 1.

Examples of X-ray contrast agents

Contrast agent (or tissue)	μ (cm2/g)*	Density (g/cm3)	Application	Dose (/Kg body weight)	Reference
Iohexol	1.093	0.924	Cardiac angiography, liver imaging	~600 mg I	51
Iodixanol	1.156	2.295	Cardiac angiography	~600 mg I	52–53
Diatrizoate	1.454	1.66	Cardiac angiography	600 mg I	54–58
Ioxaglate	1.408		Cardiac angiography	600 mg I/m	58–60
Silver iodide	2.130	5.675	Retrograde pyelography, liver imaging	400 mg	61–63
Cesium chloride	1.969	3.99	Bronchography	~400 mg	61, 64
Barium sulfate	1.616	4.5	Gastrointestinal tract	100 mg	65–66
Bismuth subnitrate	1.437	4.93	Gastrointestinal tract		67–68
Bismuth sulfide	1.813	6.78	Gastrointestinal tract	120 mg	69–71
Gold nanoparticle	1.72	19.32	Vascular casting, tumor	1000~2700 mg	36, 72
Silver nanoparticle	1.907	10.49	Vascular casting	27 mg	37
Gadolinium oxide	2.511	7.4	Hepatobiliary	200~400 mg	38, 42, 73–75
Gadolinium-DTPA**	0.855		Angiography	0.3 mmol	76
Ytterbium-DTPA**	0.935		Angiography		45, 77–80
Stannic oxide	1.660	6.95	Liver imaging	350 mg Sn	81–86
Calcium tungstate	1.871	6.06	Bronchography		87–89
Thorium oxide	2.223	10.00	Cerebral arteriography, liver imaging	230 mg	90–91
Tantalum oxide	2.399	8.2	Gastrointestinal tract, hypervascular tumors		92–93

^*:The mass-weighted attenuation coefficient is for 80 KeV X-rays. The mass-weighted attenuation coefficient for soft tissue and cortical bone are 0.182 and 0.223 cm²/g, respectively. Note: the linear attenuation coefficient, μ (cm⁻¹) is the product of the mass-weighted coeffeficient times the density.

^**:DTPA is gadopentetic acid