Prior to laser vision correction, ODs carefully examine the cornea. They evaluate the tear film, meibomian glands, curvature of both the front and back of the cornea; and measure overall corneal thickness.
Previously by Dr. Owen: How to determine an ideal LASIK candidate
At the start of my career, cataract surgery was not a refractive procedure, it was just becoming a safe medical procedure.
Today, cataract surgery benefits from precise measurements of the length of the eye and curvature of the cornea, and precise placement of the intraocular lens (IOL) to achieve a desired refractive outcome. The removal of visually disruptive cloudy lens seems almost secondary.
Once a visually significant cataract has been identified in a motivated patient, the task of setting expectations begins. All clinical facts need to be gathered before the discussion of premium lens can start.
Findings as benign as posterior vitreous floaters can create visual disturbances that may impact the success of multifocal IOLs and should be pointed out to patients prior to surgery. Additionally, pupil motility and iris defects can signal pseudoexfoliation (PXF), which is important to know prior to surgery.
The cataract patient should undergo a similar work-up of the ocular surface and its supporting structures as a contact lens patient or a laser vision correction patient. The significant difference is that positive findings do not prevent the procedure—they simply guide the IOL selection and temper expectations.
1. Trattler WB, Majmudar PA, Donnenfeld ED, Stonecipher KG, Goldberg DF. The prospective health assessment of cataract patients’ ocular surface (PHACO) study: the effect of dry eye. Clin Ophthalmol. 2017 Aug 7;11:1423-1430.
2. Epitropoulos AT, Matossian C, Berdy GJ, Malhotra RP, Potvin R. Effect of tear osmolarity on repeatability of keratometry for cataract surgery planning. J Cataract Refract Surg. 2015 Aug;41(8):1672-7.
3. Montano M, Lopez-Dorantes KP, Ramirez-Miranda A, Graue-Hernandez EO, Navas A. Multifocal toric intraocular lens implantation for forme fruste and stable keratoconus. J Refract Surg. 2014 Apr;30(4):282-285.
4. Kamiya K, Shimizu K, Miyake T. Changes in astigmatism and corneal higher-order aberrations after phacoemulsification with toric intraocular implantation for mild keratoconus with cataract. Jpn J Ophth. 2016 Jul;60(4):302-8.