CataracTools is an android app focused on helping eye doctors in their daily routine and become one of the basic tools for cataract surgery. It is currently in early stages of development and, therefore, it is not available at Google Play.
Sulcus lens calculator
With this tool you’ll be able to choose the best lens power for the eye of your patient. First, enter the power and the A constant of the lens in the bag, the app will tell you the power of the most common lenses. Alcon MNA60AC, Sensar AR40e and Tecnis ZA9003 are shown by default, but custom lenses are available.
Though the “rule of the nines” is widely used, our calculator offers a more precise approach. Generally speaking, during surgery we insert the lens with the closest lens power to emmetropia in the bag. When facing sulcus implantation, we have to decrease the power by -0.5, -1 and -1.50 depending on the power lens1-3. Then, the A constant difference is applied. Therefore, a triple source of error is affecting our decision.
With our app, a custom modification is applied to every single lens power and then the constant difference is applied. However, we’ll always be left with one source of error: choose the lens power with the closest to 0 result. Using the emmetropia value offered by your biometer, you’ll get the most accurate result possible.
Lenses with optics captured by the capsulorexis are expected to have the same power behaviour than lenses in the bag4. So, if you intend to capture it, choose the lens on the right column.
Iris Claw Calculator
With this formula, you’ll obtain a quick calculation of the appropriate lens power. You just have to enter the desired lens in the bag power and its constant and he app will automatically give you the suggested iris claw lens power.
Both prepupillary and retropupillary options have been considered and added to the app. However, only Artisan lenses are included by default. Let us know which other lenses you’d like to see included in the app.
IOP correction according to corneal thickness
Features the correction table used for adjusting intraocular pressure based on central corneal thickness (CCT)4. This includes just the table. Actually, a searching box and button were considered, but scrolling through the table gives the fastest result.
Though the app is in an early stage of development, you can already download it and give it a try. It’s currently free but it hasn’t been uploaded to Google Play, yet.
Version 0.3a: Added Kane IOL calculator (just a web browser)
Version 0.2a: Added IOP-CCT table
Version 0.1a: Initial version with Sulcus and Iris claw calculator
We are currently working in implementing a lens database with a lens algorithm based on corneal spherical aberration, a polypseudophakia calculator and some other features. But everything still being in early alpha stage, suggestions and feedback are greatly appreciated. As you’ll see, app design is not our first priority… a logo hasn’t still been added to the app and the aesthetic approach is still very raw.
What would you like to see implemented? What are your needs? We’ll gladly help, if feasible.
- Kim T, DelMonte DW, Gupta PK, Chang DF, Editors. Curbside Consultation in Cataract Surgery. 2nd ed. NJ: Slack incorporated; 2014:153–167
- Chang DF, Masket S, Miller KM, et al. Complications of sulcus placement of single-piece acrylic intraocular lenses: recommendations for backup IOL implantation following posterior capsule rupture. J Cataract Refract Surg. 2009;35(8):1445–1458. doi:10.1016/j.jcrs.2009.04.027
- Millar ER, Allen D, Steel DH. Effect of anterior capsulorhexis optic capture of a sulcus-fixated intraocular lens on refractive outcomes. J Cataract Refract Surg. 2013 Jun;39(6):841-4. doi: 10.1016/j.jcrs.2012.12.034. Epub 2013 Apr 6. PMID: 23571288.
- Patwardhan, Ashish A et al. “The importance of central corneal thickness measurements and decision making in general ophthalmology clinics: a masked observational study.” BMC Ophthalmology 8 (2008): 1 – 1.