The Power of Relaxivity and its Impact on Image Quality

Relaxivity is one of the key parameters that determines the technical efficacy of a gadolinium-based contrast agent (GBCA). The relaxivity of a GBCA is a measure of how much the GBCA enhances the water relaxation rate. Shortening of the T1 relaxation time by the GBCA will increase signal intensity on a T1-weighted image.

This process of enhanced relaxation occurs as water molecules interact with the inner coordination sphere of the gadolinium ion inside the GBCA. The molecular structure of the GBCA determines how effectively this process occurs as water molecules are exchanged one-by-one within the inner sphere. In addition to the inner sphere, there is a second sphere (or hydration sphere) where water molecules are also relaxed. Gadovist® has a special molecular structure that includes a chain of hydroxyl groups. These hydroxyl groups attract water molecules through hydrogen bonding, which helps to build a large second sphere contributing to the high relaxivity of Gadovist®.

Higher relaxivity could result in:

• Increased signal on T1-weighted images^1,2
• Enhanced image quality²
• Improved diagnostic confidence^3,4

In this video, these factors that impact relaxivity are described and the unique molecular structure of Gadovist®, which gives it the highest relaxivity of the macrocyclic GBCAs, is demonstrated.