To compare the accuracy of intraocular lens iol calculation formulas barrett universal ii, haigis, hoffer q, holladay 1, holladay. I believe in this so strongly that i had my hoffer programs iol power calculation system software completely reprogrammed so you can use the doublek, he says. Crstoday iol power calculations for multifocal lenses. Iol power calculations comparing the current third generation formulas holladay2, holladay 1, hoffer q and the srkt are easily performed. Hoffer, md on 01 december 2008 hoffersavini lasik iol power tool please click the attachment to download. Iol power calculator srkt, hoffer q, haigis, holladay i, srk ii, and binkhorst with optimized constants and astigmatic change vector analysis tool. The personalized acd pacd is developed from any given series of a particular. Significant disagreement was found using hofferq formula between the results shown by the study program and iolmaster, while identical.
Comparison of okulix raytracing software with srkt and hofferq formula in. Hoffer and savini worked on creating the spreadsheet for 2 years. This software is a professional ophthalmology calculator. Hoffer presents his variation of the colenbrander formula for iol power calculation. Theres not one, but dozens of papers, and each of those papers has 100, 200 or maybe thousands of eyes, so theres some consistency there, where you know that this has been tested again and again. Each of these formulae estimates the position of the iol. Aramberris doublek idea does make a difference, and its quite important. The hoffer q, holladay i, and srkt formulae are all commonly used. When planning cataract surgery, one of the most crucial stages for treatment success is choosing the correct intraocular lens iol power. To ease the calculation of formulas he first used early programmable calculators hp 65, and in 1993 produced the first program for iol power calculation for personal computers hoffer programs. Rosenfeld also recommended these calculation tools. The appropriate iol power was measured for each formula, using the software of. Iol power calculator for cataract surgery hillrbf calculator. It will correct the formulas from the refractive data and topography in postrefractive cases.
Calculations on patients with axial lengths of between 22 and 25 mm with corneal powers of between 42. Piggy back lens calculations now consider the minimum and maximum available power in a specific iol to simply calculations. Lets say youre using the hoffer q formula and start out with a personal. Experts provide their thoughts on how to get as close to target as possible. Theoretical difference in the predicted refraction between the hoffer q and haigis formulae for intraocular lens power calculation with varying anterior chamber depth and corneal power when the axial length was set to 22. Intraocular lens power calculation in eyes with short axial length. Even if you dont know what the preop k was, youll be better off. If less than 200 valid cases are submitted, only the a0 haigis constant will be optimized with the haigis a1 and the. A more accurate choice may be using the holladay 2 software because it. Theoretical calculation of correct iol power after corneal refractive surgery go to academy store learn more and purchase. Iol power calculation formulas zeiss medical technology. To compare the results of four different calculation formulas, select multi formula, then one of the four selection boxes for the desired formula. East valley ophthalmology 5620 east broadway road mesa, arizona 85206 tel. Hoffer q formula iol intraocular lens power calculations.
Recently, in a database study of 8,108 eyes undergoing cataract surgery, the hoffer q formula was found to provide the best refractive outcomes in eyes shorter. Comparison of iol power calculations by the iolmaster vs. He added that some surgeons are not convinced of the importance of personalizing. Hoffersavini spreadsheet for iol calculation after lasik. This is the standard situation and the respective constants may be considered as default constants. Participants in our study were 69 consecutive patients. Network setup is simple with all of the security protections now present no longer causing problems for multiple users on the same station. Iol power calculator and astigmatic change vector analysis tool. Crsteurope hoffersavini spreadsheet for iol calculation. Nov 25, 2012 to evaluate and compare the predictive capacity of four intraocular lens iol power calculation formulas srkt, hoffer q, holladay 1, and haigis in eyes shorter than 22.
It is intended to be used in conjunction with a comprehensive ophthalmic examination and the appropriate diagnostic tests and measurements necessary for cataract surgery candidates with a history of prior refractive surgery. If no number appears, it means that the formula is not applicable for that combination of axial length and refractive correction. Comparison of okulix raytracing software with srkt and hoffer q formula in intraocular lens power calculation. Features for calculating surgicallyinduced astigmatism and backcalculating values to determine the source of refractive surprises only require clicking one button. Accuracy of intraocular lens calculation formulas ophthalmology. Comparison of hoffer q and haigis formulae for intraocular. The popular thirdgeneration formulas, the hoffer q, holladay i and the. Intraocular lens power calculation in eyes with short axial. Holladay, md, contains the international iol registry and information about dr.
Hoffersavini lasik iol power tool welcome to the iol power. The hoffer q formula followed in 1993, using a tangent of k as an additional elp predictor. Using the correct iol calculation formula is important for good surgical outcomes. To print out the page with the results, press print iol calculation data.
Iol power calculation formulas which modern intraocular lens iol calculation formula gives the best results for prediction of the effective lens position elp is a widely debated topic. Srk ii, srkt, holladay, hoffer q, haigis clinical history and contact lens fitting method for calculation of the corneal refractive power subsequent to refractive corneal surgery haigisl for iol calculation for eyes after myopichyperopic lasikprklasek. According to clinical studies, the srkt formula is recommended for rather long eyes whereas the hoffer q formula is recommended for rather short eyes. Theoretical calculation of correct iol power after corneal. Iol power calculations formulas haigis holladay hoffer srt.
A different version of the olsen formula is available in a standalone software package phacooptics, iol innovations aps, aarhus, denmark, which has been reported to have slightly better outcomes than the version currently included with the lenstar 900 biometer evaluated in this study. In 450 eyes of one style iol implanted by one surgeon, the hoffer q formula was equal to the holladay p. Holladay 1, holladay 2, haigis, srk 2, srkt, hoffer iol measurement instruments need to transfer the data to an external computer as well as purchase of a separate software package for holladay 2 calculation. Surgeons discuss ways to take advantage of new iol formulas or optimize the. Since the introduction of the iol, researchers and clinicians alike have been trying to determine the best formula to use to implant the best possible lens for a particular patient, based on numerous characteristics that include refractive error, axial length, ocular comorbidities, and previous surgery.
The olsen formula uses ray tracing to get the preop lens thickness and. This works fine in the average eye but leads to limited prediction accuracy in unusual as well as long or short eyes. Sayegh believes that hoffer q is a good choice for iol calculation in short eyes, based on consistent evidence in the literature. Standard iol calculation formulae such as srkt, holladay 1 or hoffer q all estimate the effective lens position elp based on axial length and k measurements. Hoffer said its a matter of being consistent with your iol selection and making a habit of going back 1 to 3 months postop to input the patients iol power and refraction data. The iol calculator is meant to serve as an adjunct tool to assist physicians in selecting the appropriate iol for a particular patient. Most iol power calculation programs provide either internal software or specific recommendations for how to go about lens constant optimization. Holladay iol consultant software professional software. Hoffersavini spreadsheet for iol calculation after.
Iol power calculation formulas explained zeiss medical. Table 3 shows the medaes and predicted refractive errors of subgroups according to acd values 2. Ocular surgery news lens power calculations should really be referred to as. The corneal power must be entered in diopters and not mm. To compare the results of four different calculation formulas, select multi formula, then one of the four selection boxes for the desired formula select iol calculation to display the results to print out the page with the results, press print iol calculation data. It is identical to the colenbrander formula, except for a term r, which he did not identify. In this section youll find an overview of the latest generation of formulas for rotationally symmetrical iol designs postlaser vision correction eyes are. The aim of an accurate intraocular lens power calculation is to provide an intraocular lens iol that fits the specific needs and desires of the individual patient. In an ideal case, the prerefractive k readings and the exact amount of refractive correction are known and presumed accurate. Dec 06, 2011 iol calculation was performed using the haigisl formula included in the iolmaster software version 4 onwards.
The holladay iol consultant program calculates the iol power with the holladay 2 formula with its enhanced algorithm, and compares the results to the holladay 1, hoffer q, and srkt formulas. Accurate intraocular lens iol power calculation in cataract surgery is very important to. Challenges and approaches in modern biometry and iol calculation. Based on the aramberri double k method, the numbers in each row of the hyperopic refractive correction represent the amount in diopters that must be subtracted from the calculated iol power when using the hoffer q formula. The commonly used thirdgeneration formulae are the holladay 1, the srkt t for theoretical and the hoffer q. Srk i and ii regression formulae are now regarded as obsolete. The development of better instrumentation for measuring the eyes axial length al and the use of more precise mathematical formulas to perform the appropriate calculations have significantly improved the accuracy with which the. Iol calculation formulas explained zeiss medical technology. Iol power calculations formulas haigis holladay hoffer srtk. To compare the accuracy of intraocular lens iol calculation formulas barrett universal ii, haigis, hoffer q, holladay 1, holladay 2, olsen, and srkt in the prediction of postoperative refraction using a single optical biometry device. Hoffersavini lasik iol power tool written by kenneth j. For cases outside this range, the holladay 2 should be used to ensure accuracy.
In collaboration with giacomo savini, of bologna, italy, kenneth j. Comparison of anterior chamber depth and differences between predicted refractive errors as predicted by the hoffer q and haigis formulae for intraocular lens power calculation. The hoffer q formula relies on a personalized acd, al and corneal curvature. The iol power in this software calculated with new and old generation of calculation formulas of srkt, hoffer q, haigis, holladay i, srk ii, and binkhorst. Currently, wolfgang haigis, md, of wurzburg, germany, and i carry out surgeonspecific optimization of the three haigis formula variables. Three iol brands were used and for all eyes, iol power calculation was performed using. A different version of the olsen formula is available in a standalone software package phacooptics, iol innovations aps, aarhus. Biometry biometry is the process of measuring the power of the cornea keratometry and the axial length of the eye, by using this data to determine the ideal intraocular lens power measurement of axial lengthal ascan iol master.