Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus
Purpose: This study aimed to evaluate the theoretical influence on intraocular lens power (PIOL) calculation of the use of keratometric approach for corneal power (Pc) calculation in keratoconus and to develop and validate an algorithm preliminarily to minimize this influence. Methods: Pcwas calcula...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Wolters Kluwer Medknow Publications
2017-01-01
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| Series: | Indian Journal of Ophthalmology |
| Subjects: | |
| Online Access: | http://www.ijo.in/article.asp?issn=0301-4738;year=2017;volume=65;issue=8;spage=690;epage=699;aulast=Camps |
| _version_ | 1818318358673620992 |
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| author | Vicente J Camps David P Piñero Esteban Caravaca Dolores De Fez |
| author_facet | Vicente J Camps David P Piñero Esteban Caravaca Dolores De Fez |
| author_sort | Vicente J Camps |
| collection | DOAJ |
| description | Purpose: This study aimed to evaluate the theoretical influence on intraocular lens power (PIOL) calculation of the use of keratometric approach for corneal power (Pc) calculation in keratoconus and to develop and validate an algorithm preliminarily to minimize this influence. Methods: Pcwas calculated theoretically with the classical keratometric approach, the Gaussian equation, and the keratometric approach using a variable keratometric index (nkadj) dependent on r1c(Pkadj). Differences in PIOLcalculations (ΔPIOL) using keratometric and Gaussian Pcvalues were evaluated. Preliminary clinical validation of a PIOLalgorithm using Pkadjwas performed in 13 keratoconus eyes. Results: PIOLunderestimation was present if Pcwas overestimated, and vice versa. Theoretical PIOLoverestimation up to −5.6 D and −6.2 D using Le Grand and Gullstrand eye models was found for a keratometric index of 1.3375. If nkadjwas used, maximal Δ PIOLwas ±1.1 D, with most of the values ≤±0.6 D. Clinically, PIOLunder- and over-estimations ranged from −1.1 to − 0.4 D. No statistically significant differences were found between PIOLobtained with Pkadjand Gaussian equation (P > 0.05). Conclusion: The use of the keratometric Pcfor PIOLcalculations in keratoconus can lead to significant errors that may be minimized using a Pkadjapproach. |
| first_indexed | 2024-12-13T09:51:57Z |
| format | Article |
| id | doaj.art-7fa83bd84c1f42ce90b6a3d58ef63a63 |
| institution | Directory Open Access Journal |
| issn | 0301-4738 1998-3689 |
| language | English |
| last_indexed | 2024-12-13T09:51:57Z |
| publishDate | 2017-01-01 |
| publisher | Wolters Kluwer Medknow Publications |
| record_format | Article |
| series | Indian Journal of Ophthalmology |
| spelling | doaj.art-7fa83bd84c1f42ce90b6a3d58ef63a632022-12-21T23:51:54ZengWolters Kluwer Medknow PublicationsIndian Journal of Ophthalmology0301-47381998-36892017-01-0165869069910.4103/ijo.IJO_274_16Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconusVicente J CampsDavid P PiñeroEsteban CaravacaDolores De FezPurpose: This study aimed to evaluate the theoretical influence on intraocular lens power (PIOL) calculation of the use of keratometric approach for corneal power (Pc) calculation in keratoconus and to develop and validate an algorithm preliminarily to minimize this influence. Methods: Pcwas calculated theoretically with the classical keratometric approach, the Gaussian equation, and the keratometric approach using a variable keratometric index (nkadj) dependent on r1c(Pkadj). Differences in PIOLcalculations (ΔPIOL) using keratometric and Gaussian Pcvalues were evaluated. Preliminary clinical validation of a PIOLalgorithm using Pkadjwas performed in 13 keratoconus eyes. Results: PIOLunderestimation was present if Pcwas overestimated, and vice versa. Theoretical PIOLoverestimation up to −5.6 D and −6.2 D using Le Grand and Gullstrand eye models was found for a keratometric index of 1.3375. If nkadjwas used, maximal Δ PIOLwas ±1.1 D, with most of the values ≤±0.6 D. Clinically, PIOLunder- and over-estimations ranged from −1.1 to − 0.4 D. No statistically significant differences were found between PIOLobtained with Pkadjand Gaussian equation (P > 0.05). Conclusion: The use of the keratometric Pcfor PIOLcalculations in keratoconus can lead to significant errors that may be minimized using a Pkadjapproach.http://www.ijo.in/article.asp?issn=0301-4738;year=2017;volume=65;issue=8;spage=690;epage=699;aulast=CampsCataract surgeryintraocular lens powerkeratoconuskeratometric indexkeratometry |
| spellingShingle | Vicente J Camps David P Piñero Esteban Caravaca Dolores De Fez Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus Indian Journal of Ophthalmology Cataract surgery intraocular lens power keratoconus keratometric index keratometry |
| title | Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus |
| title_full | Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus |
| title_fullStr | Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus |
| title_full_unstemmed | Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus |
| title_short | Preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus |
| title_sort | preliminary validation of an optimized algorithm for intraocular lens power calculation in keratoconus |
| topic | Cataract surgery intraocular lens power keratoconus keratometric index keratometry |
| url | http://www.ijo.in/article.asp?issn=0301-4738;year=2017;volume=65;issue=8;spage=690;epage=699;aulast=Camps |
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