Challenging Cases Of Toric Iol Power Calculation, Associated With High Irregular Astigmatism.

To describe the clinical approach used in Pentagram eye hospital for the calculation of toric IOLs in cases of different etiology of high irregular astigmatism.

Three patients: a 60-year-old patient who underwent penetrating keratoplasty five years ago; a 68-year-old patient with keratoconus; a 67-year-old patient who underwent radial keratotomies for myopia 30 years ago. All of the presented patients are with BCVA lower than 0.2 decimal, corneal astigmatism greater than five diopters and developed senile cataract.

All patients have gone through detailed examination including standard optical biometry in 2.4/3.3 mm zones and SWEPT OCT biometry, evaluating posterior corneal curvature; corneal topography with axial and keratometric maps in 3/6/9 mm zones;  corneal tomography and photopic/mesopic pupil size. The main evaluated factors were topographic and keratometric specifics of astigmatism. Depending on strictly individual characteristics, toric IOLs were calculated. The cataract surgery went through computer assisted phacoemulsification methodology using Zeiss Callisto system.

The patients were examined on the thirtieth day after the surgery. The examination included objective (OR) and subjective refraction, UCVA and BCVA examination, wavefront aberrometry and photopic/mesopic pupil size. Patient №1 demonstrated OR of +1,75/-2,00/135* and UCVA =0.8 /Decimal/. Patient №2 demonstrated OR of +0,00/+0,75/135* and UCVA =0.7. The third patient demonstrated OR=+0.25/-1.25/142* and UCVA=0.7/Decimal. None of the patients required correction. Mainly high order aberrations were measured.

Implantation of toric IOLs in patients with severe corneal pathology, associated with high irregular astigmatism, is a clinical methodology that gives satisfactory visual outcomes with no practical need of postoperative optical correction. We believe that this strictly individualized and complex approach ensures good visual rehabilitation and life quality. FINANCIAL DISCLOSURE: None