After the age of 40, most people develop presbyopia. A person aged around 37 or 38 years who is mildly (+0.50–0.75 D) hyperopic for distance simply accommodates and does not need to wear glasses.
However, by the time that person turns 40, near work is hindered by bouts of blurring, accommodative asthenopia and headaches. A person who has never worn spectacles before is now faced with needing them for both distance and near vision. This problem gets worse with time as the presbyopia increases and residual accommodation decreases.
A 60-year-old woman, a former Bollywood movie star, presented with recurrent headaches. On examination, she had spectacle prescription of OD +1.00 D for distance, +3.5 D for near, and OS +1.25 D for distance and +3.75 D for near.
After a thorough diagnostics workup, including optical coherence tomography (OCT) (AngioVue Imaging System; Optovue), biometry (IOL Master 700; Carl Zeiss) and slit-lamp examination (BQ 900; Haag-Streit), I identified the problem. The patient did not want to wear spectacles and had actually never worn them, even though she owned a pair.
She claimed not to be an avid reader; however, I noticed that she used her smartphone frequently in the office, and she reported that she used her tablet quite often. After some observation and subsequent conversation, she admitted that she read on her smartphone all day and was a frequent user of social media and networking sites.
I explained that her persistent headache was due to slight hyperopia coupled with presbyopia, and that without correction and an adjustment of her current habits her headaches would not go away.
For this patient, I had to face the fact that she would never wear spectacles and had a high need for excellent near and intermediate vision. After patient counselling it became clear that she would accept a loss of contrast for distance. Additionally, because she did not drive, I had no concerns with night-time halos.
Considering these facts, I decided that the best solution for her was a clear lens exchange with implantation of a trifocal IOL.
I counselled the patient about the clear lens exchange technique and procedure, including risks as well as benefits. This included a preoperative data assessment with a full-length OCT image (IOLMaster 700; Carl Zeiss) and a customised surgical plan.
I used the SRK/T formula to calculate the appropriate IOL power and decided to order trifocal IOLs (AT LISA tri 839MP; Carl Zeiss; right eye 22.5 D, left eye 23.0 D).
Cyres Keiki Mehta, MS (Ophth), MCh (Ophth)
E: [email protected]
Dr Mehta is the surgical director and chief at Dr Cyres K Mehta’s International Eye Centre, Mumbai, India, and the director at CKM Eye Specialities, Mumbai, India. Dr Mehta has no financial interest in any products or companies mentioned.
1. Shimizu K, Misawa A, Suzuki Y. Toric intraocular lenses: correcting astigmatism while controlling axis shift. J Cataract Refract Surg. 1994;20:523-526.