FAIRFAX, Va. – June 2, 2016 – The American Society of Cataract and Refractive Surgery (ASCRS) is pleased to announce the launch of the Hill-RBF Calculator, now on its website at ascrs.org.
The Hill-RBF Calculator is an advanced, self-validating method for IOL power selection employing pattern recognition and sophisticated data interpolation. It has been optimized for use with the Haag-Streit LENSTAR, using optical biometry for all axial measurements and high density autokeratometry.
According to Warren E. Hill, MD, FACS, of Mesa, Arizona, who served as the project leader, “The idea behind this project was to develop a completely new, self-validating IOL power selection method that is entirely data-driven and independent of the limitations of theoretical vergence formulas.”
A unique feature of radial basis function IOL power selection is that it is free of calculation bias, performing best where it has the most data. By this method, short, normal and long eyes are simply viewed as a pattern. Equally important, this method also employs a validating boundary model, indicating to the user when it is performing within a defined area of accuracy. Conversely, if the calculator is naive to the type of measurements that have been entered, it gives the user an out-of-bounds statement.
“One problem with how we presently calculate IOL power is that current methods mostly limit possibilities to situations that are already understood,” notes Dr. Hill, whereas the advantage of pattern recognition is achieved through the process of adaptive learning. “This completely new approach has the ability to learn tasks based solely on data, independent of what is previously known. It was our objective to develop something better suited to the complex, nonlinear relationships of the various parts of the human eye,” he says. This method is also self-organizing, meaning that it has the ability to create its own organization, or representation of data.
Unlike older, static theoretical formulas, this approach will be an ongoing project and continuously updated as “big data” exercise. The greater the number of surgical outcomes that are fit to the RBF model, the greater the overall depth of its accuracy. In its preset form, the Hill-RBF Calculator has been optimized for biconvex IOLs from +6.00 D to +30.00 D, but in the near future, the boundary model will be expanded to +40.00 D. “After that,” says Dr. Hill, “we will also include meniscus design IOLs, such as those with a power below +6.00 D.”
The product of six years of research, the Hill-RBF Calculator is a collaboration between a team of 24 surgeons in 13 countries, Haag-Streit Switzerland and MathWorks. “The fundamental premise of this project is to increase patient safety and physician confidence, and reduce the many burdens associated with a postoperative refractive surprise,” says Dr. Hill, who worked closely with core investigators Doug Koch, MD, and Li Wang, MD, PhD, in Houston; Adi Abulafia, MD, in Israel; and David Goldblum, MD, in Switzerland.
For more information about the Hill-RBF Calculator, contact Dr. Hill at firstname.lastname@example.org. The Hill-RBF Calculator may be found under “Online Tools” at ascrs.org.
The American Society of Cataract and Refractive Surgery is an international educational society with more than 9,000 members. Its mission is to advance the art and science of ophthalmic surgery and the knowledge and skills of ophthalmic surgeons by providing clinical and practice management education and by working with patients, government and the medical community to promote the delivery and advancement of high-quality eye care. ascrs.org