Dear Editor,
We read the article titled “Comparison of the clinical outcomes of Eyecryl™ and Tecnis® toric intraocular lenses: A real-world study” by Thulasidas M et al.[1] published in the Indian Journal of Ophthalmology, with great interest. We congratulate all the authors for their publication. The authors have conducted the study to analyze the visual and refractive outcome of Indian-made Eyecryl™ toric IOL and compare it with an already established global toric IOL (Tecnis®) in the real-world setting. However, there were various shortcomings that we had come across and wanted to raise in front of the readers.
First of all, as correctly mentioned by the authors, the major drawback of the study is its retrospective design. A prospective, randomized control trial would have been an ideal study design to evaluate the outcomes of a toric IOL. Sample sizes in group 1 and group 2 were 38 eyes and 70 eyes, respectively. The authors have not mentioned how the sample size was calculated. The disproportionate sample size can alter the study outcomes and adversely affect the study’s merit. Another aspect is that it was a multisurgeon operated study. The authors did not mention how many surgeons were enrolled in the study and whether they were dedicated to a particular group. In an ideal situation, a single surgeon study would have been a better option as the experience of various surgeons may affect the outcome.
Preoperative axis markings were done manually under a slit lamp. The authors did not mention whether the same person or respective operative surgeon did the markings. During the surgical procedure, the authors mentioned that viscoelastic substances were removed after the final alignment of the toric IOL. In an ideal situation, we should keep the TIOL 10–20 degrees off-axis of the intended position. The final alignment should be done after complete OVD removal.[2] The importance of behind the IOL OVD removal and early postoperative IOP spike has not been discussed.[3]
Postoperatively, the axis of implanted toric IOL was assessed with the fully dilated pupil at the slit lamp, a rotating slit, and a rotational gauge. However, it has not been mentioned whether the same observer or multiple observers noted the findings. Moreover, the mean deviation of IOL from the target position or the rotational stability was not adequately assessed. Updated technology such as ray tracing aberrometry (iTrace) would elicit the findings more accurately.[4] As correctly mentioned by the authors, prospective, randomized controlled trials with longer follow-up can provide important information regarding the Indian-made Eyecryl™ toric IOL, which is more affordable for the patients in our country.
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Conflicts of interest
There are no conflicts of interest.
References
- 1.Thulasidas M, Sasidharan A, Pradeep B. Comparison of the clinical outcomes of Eyecryl™and Tecnis®toric intraocular lenses:A real-world study. Indian J Ophthalmol. 2022;70:801–6. doi: 10.4103/ijo.IJO_1650_21. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Kaur M, Shaikh F, Falera R, Titiyal JS. Optimizing outcomes with toric intraocular lenses. Indian J Ophthalmol. 2017;65:1301–13. doi: 10.4103/ijo.IJO_810_17. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Chen Y, Cao Q, Xue C, Huang Z. Comparison of two techniques for toric intraocular lens implantation:Hydroimplantation versus ophthalmic viscosurgical devices. BMC Ophthalmol. 2018;18:1–7. doi: 10.1186/s12886-018-0758-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4.Farooqui JH, Sharma M, Koul A, Dutta R, Shroff NM. Evaluation of a new electronic preoperative reference marker for toric intraocular lens implantation by two different methods of analysis:Adobe Photoshop versus iTrace. Oman J Ophthalmol. 2017;10:96–9. doi: 10.4103/ojo.OJO_163_2013. [DOI] [PMC free article] [PubMed] [Google Scholar]