Figure 1: PreciSAL Toric Quadrants
The quadrants of a PreciSAL Toric IOL. The two steeper quadrants have increased curvature (added power) for the cylinder, and blend crisply with the flatter (reduced power; marked with three dots) quadrants for the sphere. The cylinder quadrants have a straight and minimal transition zone to the sphere, meaning the cylinder correction covers up to 85 o of the available 90o surface. The quadrants also extend to within 0.5mm of the optic edge, so the power is more precise across a significantly greater area than from competing toric IOLs. PreciSAL Toric with AccuPlaceTM is more forgiving of both rotation and off-axis implantation, as well as providing a crisp, clear astigmatic correction.
Figure 2: Transition angle
The 2.5o transition angle used by MBI when lathing the cylinder onto the optic. The maximum available area is used for the toric correction, reducing susceptibility to rotation or miss-alignment. The cylinder edge transition is also straight from the centre to the edge, giving a crisp, clear astigmatic correction unparalleled in toric IOLs.
Figure 3: Topographic vision and MTF Histogram
The topographic images (above left), compare the Toric quadrant definition between PreciSAL Toric (Top) and the industry standard. The superior PreciSAL technology is also highlighted by the histograms (above right), the precise transition edge of PreciSAL between cylinder and sphere with minimal transition can be seen on the optical bench (top), showing the maximum available area topographically, with the desired smooth and straight ‘M-shaped’ histogram peaks, when compared with the industry standard (bottom).