Fellow Eye Data for IOL Calculation in Eyes Undergoing Combined Phacovitrectomy

Fellow Eye Data for IOL Calculation in Eyes Undergoing Combined Phacovitrectomy | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Fellow Eye Data for IOL Calculation in Eyes Undergoing Combined Phacovitrectomy Thomas Kohnen, Klemens Kaiser, Julian Bucur, Tyll Jandeworth, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3663811/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose To evaluate whether the intraocular lens (IOL) calculation of the fellow eye (FE) can be used in eyes undergoing combined phacovitrectomy. Methods In this retrospective, consecutive case series, we enrolled patients who underwent silicone oil (SO) removal combined with phacoemulsification and IOL implantation at the Department of Ophthalmology, Goethe University, Frankfurt, Germany. Preoperative examinations included biometry using the IOL Master 700 (Carl Zeiss Meditec AG, Jena, Germany). We used the IOL calculation of the FE (FE group) to calculate the prediction error compared with the IOL calculation using only the axial length of the FE (AL-FE group), as well as using the axial length (AL) of the operated eye (OE group) in addition to the measurable biometric parameters. For the IOL calculation, the Barrett Universal II formula was used. We compared the mean prediction error (MPE) as well as the mean (MAE) and median absolute prediction error (MedAE) with each other. In addition, the number of eyes with ± 0.50, ± 1.00, and ± 2.00 diopters (D) deviation from the target refraction was compared. Results In total, 79 eyes of 79 patients met our inclusion criteria. MedAE was lowest in the OE group (0.41 D), followed by FE group (1.00 D) and AL-FE group (1.02 D). Comparison between the AL-FE and FE groups showed no statistically significant difference (p = 0.712). Comparing eyes within ± 0.50 D of the target refraction, the OE group (50 eyes, 63.3%) performed best, followed by the AL-FE group (22 eyes, 27.8%) and the FE group (21 eyes, 26.6%). Conclusion Our results indicate no clinically relevant difference between using the IOL calculation of the fellow eye versus using only the axial length of the fellow eye in addition to the measurable parameters for the IOL calculation. A two-step procedure should always be strived for. IOL calculation phacovitrectomy retinal detachment fellow eye Figures Figure 1 Figure 2 SUMMARY BOX What was known before: In eyes with a macular-involving rhegmatogenous retinal detachment, it is difficult to measure the correct axial length, which limits the predictability of the intraocular lens calculation. Using the axial length of the fellow eye results in less predictable calculation of the postoperative refraction compared to using the axial length of the oil filled eye. What this study adds: Using the calculation of the intraocular lens of the fellow eye is not inferior to using the axial length of the fellow eye in combination with the measurable biometric parameter of the affected eye. INTRODUCTION With an incidence of approximately one in 10,000 people per year, rhegmatogenous retinal detachment (RD) is among the main emergency indications in ophthalmology which can cause moderate to severe visual impairment 1 . Pars plana vitrectomy (PPV) with vitreous body replacement by oil, gas, or air has been established as one of the most effective procedures with a satisfying postoperative anatomical success rate of roughly 90% 2 . When planning the surgical management of eyes with RD, the surgeon needs to consider pre-existing lens opacification or cataracts to ensure clear visualization during surgery. In addition, PPV leads to cataract progression, and subsequent cataract surgery may be necessary within one year after initial vitrectomy 3 . Recent advances in surgical technology have enabled the ophthalmic surgeon to provide combined management of both cataract and retinal pathology. Combined vitrectomy with phacoemulsification and implantation of an intraocular lens has been shown to decrease visual rehabilitation time in patients with early significant cataracts 4 . Combined phacovitrectomy is associated with a significant reduction in overall healthcare costs, which may become more and more important in times of healthcare reform 4,5 . Furthermore, it can be assumed that combined surgery reduces the ecological footprint. In cases of macula-involving RD, even modern ocular biometry devices as well as the traditional A-scan can have difficulties measuring the axial length (AL) 6 . This can also be the case in proliferative vitreoretinopathy, diabetic eyes, vitreous hemorrhage, or pronounced vitreous opacity, for instance. In such cases, the intraocular lens (IOL) calculation of the fellow eye can be used, since most patients have similar ocular biometry comparing both eyes 6,7 . In a recently published study, we investigated whether the AL of the fellow eye in combination with the measurable biometric parameters of the affected eye can be used for IOL calculation. In this study we showed that the use of the AL of the fellow eye leads to a clinically and statistically significant reduction of the IOL power predictability and a two-stage procedure with measurement of the AL after reattachment of the retina is recommended for the best possible IOL outcome 8 . Nevertheless, in some cases, combined surgery is inevitable, for example when complex ocular pathology or a significant cataract is present and clear visualization during surgery is necessary. In the present study, we aimed to find out whether the entire IOL calculation of the fellow eye (FE) with all its biometric results can be used in eyes undergoing combined phacovitrectomy or whether the accuracy is greater using only the axial length of the fellow eye in addition to measurable biometric parameters of the affected eye for the IOL calculation. METHODS Study design In this retrospective, consecutive case series, we enrolled patients who underwent combined phacovitrectomy with SO removal and IOL implantation and who had prior vitrectomy with SO filling due to the retinal detachment at a single center from January 2016 to May 2023. Inclusion and exclusion criteria We included pseudophakic patients with a monofocal, non-toric IOL with a history of combined phacovitrectomy and IOL implantation in the bag after prior vitrectomy with SO fill due to RD, without intra- or postoperative complications, and complete pre- and postoperative data of both the operated and fellow eye. We excluded patients with the following criteria: a history of corneal refractive surgery, ocular pathologies that could influence the postoperative refraction and missing pre- or postoperative data. Only patients who received successful simultaneous biometric measurement of the phakic fellow eye without a history of corneal refractive surgery, or other ocular pathologies that could influence the assessment of biometric parameters, were included. We excluded patients with a pseudophakic fellow eye. Preoperative and postoperative assessment We used the IOL Master 700 (Carl Zeiss Meditec AG, Jena, Germany) with an integrated partial coherence interferometer to obtain the following biometric parameters: keratometry values, horizontal corneal diameter (CD), anterior chamber depth (ACD; measured from corneal epithelium to the lens), lens thickness (LT) and axial length (AL). Objective refraction was determined by a trained technician using the Topcon KR-800S auto kerato-refractometer (Topcon Medical Systems, Inc., Oakland, NJ, USA). Postoperative refraction was measured at least four weeks after combined phacovitrectomy. The spherical equivalent was calculated by adding the sum of sphere power with half of the cylinder power. Surgical technique and intraocular lenses Phacoemulsification was performed through a 2.2-mm free corneal incision with IOL implantation into the capsular bag. For the removal of the SO, pars plana vitrectomy with three or four ports (23 gauge or smaller) and filling of the vitreous cavity with sulfur hexafluoride (SF 6 ) gas or air were performed in one session by the same surgeon. All operations were performed by three experienced surgeons at a single center (Department of Ophthalmology, Goethe University, Frankfurt, Germany). In this study, five different monofocal non-toric IOLs were implanted. The IOL calculation was performed using the suggested IOL constants for the appropriate IOL using the Barrett Universal II (BUII) formula. The different IOLs and constants for the calculation are listed in Table 1 . Table 1 IOL types, distribution and used constants IOL Type A-constant BUII N % SA60AT 118.53 4 5.1 MA60AC 119.20 4 5.1 AAB00 119.00 47 59.5 SN60WF 118.99 11 13.9 SN60AT 118.53 13 16.5 IOL = intraocular lens; BUII = Barrett Universal II; n = number; % = percent IOL power calculation The IOL power was calculated with the BUII formula using all required values of the fellow eye (FE group). In addition, we used the BUII formula for the IOL calculation of the operated eye (OE), using all required values of the OE with only the AL of the fellow eye (AL-FE group) and ( 2 ) the AL of the OE after reattachment of the retina with silicone oil (OE group). Calculations were performed in October 2023 using the Barrett Universal II Formula V1.05 provided by the Asia-Pacific Association of Cataract and Refractive Surgeons ( https://calc.apacrs.org/barrett_universal2105/ ). We only used the Barrett Universal II formula in our study since it performed best in two recently published papers, both in eyes with silicone oil endotamponade and when using the axial length of the fellow eye 8,9 . For assessing the prediction error (PE) and absolute PE of the IOL power calculated with the BUII formula, we assessed the difference between the actual postoperative spherical equivalent refraction at the spectacle plane and the predicted refraction based on the implanted IOL power. PE = predicted refraction – actual postoperative refraction Absolute PE = | predicted refraction – actual postoperative refraction | In the interpretation of the PE, a positive value means a hyperopic, and a negative value a myopic shift. The mean arithmetic prediction error (MPE), mean absolute prediction error (MAE), median absolute prediction error (MedAE), the maximum and minimum of these errors (range), as well as the percentage of eyes within ± 0.50, ± 1.00, and ± 2.00 diopters (D) deviation from the target refraction were calculated. Statistical analysis In all eyes, the pseudonymized data was collected and entered manually into an Excel sheet (Version 14.7.7, Microsoft Corporation, Redmond, WA, USA). For statistical analysis, SPSS Software (Version 29.0; IBM Corporation, Armonk, NC, USA) was used. First, a Kolmogorov-Smirnov test was used to test for normal distribution. A Friedman test, and, if significantly different, a post hoc analysis with a Wilcoxon signed-rank test or paired t-test were performed (depending on distribution) to analyze differences in MPE and MedAE. To compare the percentage of PE within ± 0.5D and ± 1.0D, the Cochrane Q test was used. P-values below 0.05 were considered statistically significant. If needed, the p-values were corrected using the Bonferroni correction. The sample size estimation was performed using the G*Power 3.1 Software (Heinrich Heine University Duesseldorf, Germany). Based on a difference between the groups of 0.1 D with a standard deviation of 0.2 D at least 47 eyes were needed to reach power of at least 80%. RESULTS In this study, 79 eyes of 79 patients matched our inclusion criteria. 28 were female and 51 were males. The mean age was 59.32 years ± 9.62 (Range: 24–82). The mean AL of the operated eye with SO fill after re-attachment of the retina was 25.27 mm ± 1.79 mm (Range: 22.06–31.72). The mean AL of the fellow eye was 25.11 mm ± 1.81 mm (Range: 22.05–32.08). The mean absolute difference of the AL of both eyes was 0.40 mm ± 0.50 mm (Range: 0.00–2.76 mm), mean relative difference was 0.15 mm ± 0.62 mm (Range: -1.26 - +2.76 mm). The Pearson coefficient between the AL of the FE and the OE was 0.943 (p < 0.001). In 23 patients, the AL was above 26.0 mm. Baseline characteristics of patients are summarized in Table 2 . Table 2 Patient Demographics Mean Standard Deviation Minimum Maximum Age (y) 59.32 9.62 24 82 AL OE (mm) 25.27 1.79 22.06 31.72 AL FE (mm) 25.11 1.78 22.05 32.08 Kmean OE (D) 42.17 1.51 38.93 45.77 Kmean FE (D) 42.12 1.36 38.47 45.32 ACD OE (mm) 3.29 0.37 2.33 4.23 ACD FE (mm) 3.30 0.33 2.43 3.96 LT OE (mm) 4.45 0.44 2.92 5.62 LT FE (mm) 4.46 0.40 3.33 5.48 IOL power (D) 18.46 4.09 6 25 Postop SE (D) -1.31 1.11 -3.75 2.00 Postop VA (decimal) 0.44 0.28 0.02 1.2 y = years; AL = Axial length, OE = operated eye; FE = Fellow eye; Kmean = mean keratometry; D = Diopters; ACD = Anterior chamber depth; LT = Lens thickness; IOL = Intraocular lens; Postop SE = Postoperative spherical equivalent; VA = Visual acuity The implanted monofocal IOLs were AAB00 (47 eyes, 59.5%), SN60AT (13 eyes, 16.5%), SN60WF (11 eyes, 13.9%), SA60AT (4 eyes, 5.1%), and MA60AC (4 eyes, 5.1%). The mean postoperative spherical equivalent was − 1.31 D ± 1.11. The mean IOL power was 18.46 D ± 4.09 (6.0–25.0 D). The follow-up was at least one month in all patients. MedAE was lowest in the OE group (0.41 D), followed by the FE group (1.00 D) and AL-FE group (1.02 D). Using Friedman’s test, the difference between the absolute error of the three groups was statistically significant (p < 0.001). Post-hoc analysis using the paired t-test with Bonferroni correction yielded a statistically significant difference between the absolute error (AE) comparing the OE group and AL-FE group (p < 0.001), as well as between the OE group and the FE group (p < 0.001). However, when comparing the differences in the AE between the FE group and the AL-FE group, there was no statistically significant difference (p = 0.960). MPE, MAE, and MedAE with standard deviation and range of all eyes are shown in Table 3 . No correlation was found between the AL of the OE and the absolute prediction error (Pearson coefficient = -0.091; p = 0.424). Table 3 Postoperative Refractive Outcomes MPE MAE MedAE SD Min Max FE Group -1.08 1.29 1.00 1.19 0.00 6.19 FE-AL Group -0.90 1.21 1.02 1.11 0.01 5.38 OE Group -0.03 0.59 0.42 0.77 0.00 5.94 MPE = Mean prediction error; MAE = Mean absolute error; MedAE = Median absolute error; SD = Standard deviation; FE = fellow eye; FE-AL = only the axial length of the fellow eye was used in combination with the measurable biometric data of the operated eye for IOL calculation; OE = operated eye Considering the number of eyes within ± 0.50 D of the target refraction, the OE group performed best with 50 eyes (63.3%). In contrast, both the FE and AL-FE groups performed considerably less favorably, with 21 and 22 eyes (26.6% and 27.8%), respectively. Using the Cochrane Q test, a statistically significant difference was found between the OE and AL-FE groups, as well as between the OE and FE groups (p < 0.001 each). Comparison between the AL-FE and FE groups showed no statistically significant difference (p = 0.712). Figure 1 shows the number of eyes within ± 1.00 and ± 2.00 D of the target refraction with likewise significantly more eyes in the OE group compared to the FE and AL-FE groups. DISCUSSION The AL of the eye is the most crucial parameter in IOL calculation 10 . A 0.1 mm error in AL is equivalent to an error of about 0.27 D in the spectacle plane 11 . Therefore, high accuracy in the assessment of the AL is a necessity. For many years, in the clinical practice ultrasound was the only technique to measure the length of the eye. The accuracy of the AL measurement has improved considerably with the implementation of optical biometry using partial coherence interferometry (PCI) 12 . Despite technical progress, it is often not possible to determine the exact AL with the PCI integrated into the ocular biometer in eyes with macular-involving retinal detachment 6 . In cases of pre-existing lens opacities or cataracts, the surgeon may use the data of the fellow eye instead of ultrasound biometry which is known to be much less accurate 6 . Some studies report sufficient results for lens power calculation and prediction of refractive outcome when biometry of the fellow eye is used 13,14 . In the present study, we investigated whether using the entire IOL calculation of the fellow eye provides reliable results, or whether the axial length of the fellow eye in combination with the measurable biometric parameters of the affected eye induces a lower refractive error when the AL of the affected eye cannot be obtained. To the best of our knowledge, studies comparing the use of the AL of the fellow eye for the IOL calculation of the affected eye with the entire biometry of the fellow eye are rare. Our results suggest that using the biometry of the FE (MedAE 1.00 D) for IOL calculations for macular-involving RD is as accurate as using only the AL of the fellow eye in combination with the measurable biometric parameters of the affected eye (MedAE 1.02 D). In our study, every second eye was within 1.0 D of its predicted refractive outcome. Comparing this with the outcome achieved when using the biometry of the operated eye after reattachment of the retina with SO fill, the IOL power predictability error is statistically and clinically significantly lower using a two-step procedure (MedAE 0.41 D) (p < 0.001). Furthermore, far more patients achieve an outcome within ± 1.0 D of prediction (84.8%). In order to avoid postoperative anisometropia, it may be useful to ask the patient preoperatively whether there are differences between the refractive values of the two eyes and to rule out preoperative anisometropia. In our opinion, it is not advisable to use the biometric values of the fellow eye if there are major differences between the eyes, in order to avoid refractive surprises. We agreed with El-Khayat et al. who determined that it is possible to use the IOL calculation of the partner eye if the refraction values of both eyes are quite similar 14 . Manual entry of the axial length into the biometry device is, based on the results of the present study, not superior to using the entire IOL calculation of the fellow eye. A definite solution for this could be an intraoperative AL measurement after reattachment of the retina 15 . However, as long as this is not possible, the results of the fellow eye show a higher predictability compared to the calculation with an AL assessed with the macula detached, but as we could show in this and the previous publication, still a significantly worse result compared to the calculation with the AL in SO-filled eyes 8 . In addition to preoperative anisometropia, conditions that may preclude the use of biometry of the fellow eye include corneal disease, poor fixation, significant media opacity, and cataract and macular elevation/edema. The limitations of our study include the retrospective setting and the fact that different IOLs were included. However, the authors believe that the sample size is sufficient for this purpose. In addition, the IOL calculation of the fellow eye and the use of the axial length of the fellow eye were only performed theoretically, without corresponding implantation of the IOL in the affected eye. To best reflect the daily practice of most clinicians, we did not optimize the constants for the IOL calculation and decided to use proven constants. In our opinion, it was not necessary to optimize the constants as biometric data of the fellow eye was used. Based on the recommendations of Hoffer and Savini for reporting IOL calculation results, it shows that optimization of IOL constants is not indicated in highly specific and rare cases, which in our view would also apply to our study 16 . However, when calculating lens replacement, accurate predictability can prevent anisometropic problems that could consecutively lead to lens surgery in the healthy eye, which could result in surgical risks such as retinal detachment or infection. CONCLUSION Our results indicate no clinically relevant difference between using the entire IOL calculation of the fellow eye versus using only the axial length of the fellow eye in addition to the measurable biometric parameters of the affected eye for the determination of the IOL power. However, a two-step procedure using the AL of the operated eye after reattachment of the retina is still highly recommended for the best possible calculation of the IOL power. Declarations Funding: No funding was received for this study. Conflict of Interest: T. Kohnen: Consultant and Research for Alcon/Novartis, J&J, Lensgen, Oculentis, Oculus, Presbia, Schwind, Zeiss. Consultant for Allergan, Bausch & Lomb, Geuder, Med Update, Santen, Staar, Thieme, Ziemer. All other authors have no financial interests to disclose. Data availability statement: All data generated or analyzed during this study are included in this article. Further enquiries can be directed to the corresponding author. Ethics approval: This study includes human participants and was approved by the ethics committee of the Goethe University Frankfurt (approval number: 2022-899). Before participating in the study, the participants gave their informed consent after been informed in detail. References Haimann MH, Burton TC, Brown CK. Epidemiology of retinal detachment. Arch Ophthalmol. 1982; 100(2): 289–292. Sultan ZN, Agorogiannis EI, Iannetta D, Steel D, Sandinha T. 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Drexler W, Findl O, Menapace R, Rainer G, Vass C, Hitzenberger CK, et al. Partial coherence interferometry: a novel approach to biometry in cataract surgery. Am J Ophthalmol. 1998; 126(4): 524–534. Knox Cartwright NE, Johnston RL, Jaycock PD, Tole DM, Sparrow JM. The Cataract National Dataset electronic multicentre audit of 55 567 operations: when should IOLMaster biometric measurements be rechecked? Eye. 2010; 24(5): 894–900. El-Khayat AR, Brent AJ, Peart SAM, Chaudhuri PR. Accuracy of intraocular lens calculations based on fellow-eye biometry for phacovitrectomy for macula-off rhegmatogenous retinal detachments. Eye (Lond). 2019; 33(11): 1756–1761. Moussa G, Sachdev A, Mohite AA, Hero M, Ch’ng SW, Andreatta W. ASSESSING Refractive outcomes and accuracy of biometry in phacovitrectomy and sequential operations in patients with retinal detachment compared with routine cataract surgery. Retina. 2021; 41(8): 1605–1611. Hoffer KJ, Savini G. Update on intraocular lens power calculation study protocols. Ophthalmology. 2021; 128(11): e115–e120. Additional Declarations There is conflict of interest Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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13:50:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3663811/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3663811/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":49385265,"identity":"5104f130-4e28-4cfc-b226-1c7910ce8343","added_by":"auto","created_at":"2024-01-09 19:50:12","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":302422,"visible":true,"origin":"","legend":"\u003cp\u003eHistogram comparing the number of eyes within ±0.5, ±1.00, and ±2.0 D from target refraction\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-3663811/v1/90b3e5b1859d4b8c81f141ec.png"},{"id":49385266,"identity":"bf579754-85e7-481e-8099-71fe645cff24","added_by":"auto","created_at":"2024-01-09 19:50:12","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":245135,"visible":true,"origin":"","legend":"\u003cp\u003eBoxplot comparing the absolute prediction error of the three groups\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-3663811/v1/1fc2b598acfb87c0a9ecee19.png"},{"id":51431110,"identity":"3d94755d-f31e-4d65-84b1-dd59ceafe9d6","added_by":"auto","created_at":"2024-02-21 13:23:29","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":433869,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3663811/v1/1b1c138c-a87f-4980-9961-3206ddad67cd.pdf"}],"financialInterests":"There is conflict of interest","formattedTitle":"Fellow Eye Data for IOL Calculation in Eyes Undergoing Combined Phacovitrectomy","fulltext":[{"header":"SUMMARY BOX","content":"\u003cp\u003e\u003cstrong\u003eWhat was known before:\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eIn eyes with a macular-involving rhegmatogenous retinal detachment, it is difficult to measure the correct axial length, which limits the predictability of the intraocular lens calculation.\u003c/li\u003e\n \u003cli\u003eUsing the axial length of the fellow eye results in less predictable calculation of the postoperative refraction compared to using the axial length of the oil filled eye. \u0026nbsp;\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eWhat this study adds:\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eUsing the calculation of the intraocular lens of the fellow eye is not inferior to using the axial length of the fellow eye in combination with the measurable biometric parameter of the affected eye.\u003c/p\u003e"},{"header":"INTRODUCTION","content":"\u003cp\u003eWith an incidence of approximately one in 10,000 people per year, rhegmatogenous retinal detachment (RD) is among the main emergency indications in ophthalmology which can cause moderate to severe visual impairment\u003csup\u003e1\u003c/sup\u003e. Pars plana vitrectomy (PPV) with vitreous body replacement by oil, gas, or air has been established as one of the most effective procedures with a satisfying postoperative anatomical success rate of roughly 90%\u003csup\u003e2\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eWhen planning the surgical management of eyes with RD, the surgeon needs to consider pre-existing lens opacification or cataracts to ensure clear visualization during surgery. In addition, PPV leads to cataract progression, and subsequent cataract surgery may be necessary within one year after initial vitrectomy \u003csup\u003e3\u003c/sup\u003e. Recent advances in surgical technology have enabled the ophthalmic surgeon to provide combined management of both cataract and retinal pathology. Combined vitrectomy with phacoemulsification and implantation of an intraocular lens has been shown to decrease visual rehabilitation time in patients with early significant cataracts\u003csup\u003e4\u003c/sup\u003e. Combined phacovitrectomy is associated with a significant reduction in overall healthcare costs, which may become more and more important in times of healthcare reform\u003csup\u003e4,5\u003c/sup\u003e. Furthermore, it can be assumed that combined surgery reduces the ecological footprint.\u003c/p\u003e \u003cp\u003eIn cases of macula-involving RD, even modern ocular biometry devices as well as the traditional A-scan can have difficulties measuring the axial length (AL)\u003csup\u003e6\u003c/sup\u003e. This can also be the case in proliferative vitreoretinopathy, diabetic eyes, vitreous hemorrhage, or pronounced vitreous opacity, for instance. In such cases, the intraocular lens (IOL) calculation of the fellow eye can be used, since most patients have similar ocular biometry comparing both eyes\u003csup\u003e6,7\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eIn a recently published study, we investigated whether the AL of the fellow eye in combination with the measurable biometric parameters of the affected eye can be used for IOL calculation. In this study we showed that the use of the AL of the fellow eye leads to a clinically and statistically significant reduction of the IOL power predictability and a two-stage procedure with measurement of the AL after reattachment of the retina is recommended for the best possible IOL outcome\u003csup\u003e8\u003c/sup\u003e. Nevertheless, in some cases, combined surgery is inevitable, for example when complex ocular pathology or a significant cataract is present and clear visualization during surgery is necessary.\u003c/p\u003e \u003cp\u003eIn the present study, we aimed to find out whether the entire IOL calculation of the fellow eye (FE) with all its biometric results can be used in eyes undergoing combined phacovitrectomy or whether the accuracy is greater using only the axial length of the fellow eye in addition to measurable biometric parameters of the affected eye for the IOL calculation.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design\u003c/h2\u003e \u003cp\u003eIn this retrospective, consecutive case series, we enrolled patients who underwent combined phacovitrectomy with SO removal and IOL implantation and who had prior vitrectomy with SO filling due to the retinal detachment at a single center from January 2016 to May 2023.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eInclusion and exclusion criteria\u003c/h2\u003e \u003cp\u003eWe included pseudophakic patients with a monofocal, non-toric IOL with a history of combined phacovitrectomy and IOL implantation in the bag after prior vitrectomy with SO fill due to RD, without intra- or postoperative complications, and complete pre- and postoperative data of both the operated and fellow eye.\u003c/p\u003e \u003cp\u003eWe excluded patients with the following criteria: a history of corneal refractive surgery, ocular pathologies that could influence the postoperative refraction and missing pre- or postoperative data.\u003c/p\u003e \u003cp\u003eOnly patients who received successful simultaneous biometric measurement of the phakic fellow eye without a history of corneal refractive surgery, or other ocular pathologies that could influence the assessment of biometric parameters, were included. We excluded patients with a pseudophakic fellow eye.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003ePreoperative and postoperative assessment\u003c/h2\u003e \u003cp\u003eWe used the IOL Master 700 (Carl Zeiss Meditec AG, Jena, Germany) with an integrated partial coherence interferometer to obtain the following biometric parameters: keratometry values, horizontal corneal diameter (CD), anterior chamber depth (ACD; measured from corneal epithelium to the lens), lens thickness (LT) and axial length (AL).\u003c/p\u003e \u003cp\u003eObjective refraction was determined by a trained technician using the Topcon KR-800S auto kerato-refractometer (Topcon Medical Systems, Inc., Oakland, NJ, USA). Postoperative refraction was measured at least four weeks after combined phacovitrectomy. The spherical equivalent was calculated by adding the sum of sphere power with half of the cylinder power.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eSurgical technique and intraocular lenses\u003c/h2\u003e \u003cp\u003ePhacoemulsification was performed through a 2.2-mm free corneal incision with IOL implantation into the capsular bag. For the removal of the SO, pars plana vitrectomy with three or four ports (23 gauge or smaller) and filling of the vitreous cavity with sulfur hexafluoride (SF\u003csub\u003e6\u003c/sub\u003e) gas or air were performed in one session by the same surgeon. All operations were performed by three experienced surgeons at a single center (Department of Ophthalmology, Goethe University, Frankfurt, Germany).\u003c/p\u003e \u003cp\u003eIn this study, five different monofocal non-toric IOLs were implanted. The IOL calculation was performed using the suggested IOL constants for the appropriate IOL using the Barrett Universal II (BUII) formula. The different IOLs and constants for the calculation are listed in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003e IOL types, distribution and used constants\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIOL Type\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eA-constant\u003c/p\u003e \u003cp\u003eBUII\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSA60AT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e118.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMA60AC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e119.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAAB00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e119.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e59.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSN60WF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e118.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSN60AT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e118.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eIOL\u0026thinsp;=\u0026thinsp;intraocular lens; BUII\u0026thinsp;=\u0026thinsp;Barrett Universal II; n\u0026thinsp;=\u0026thinsp;number; % = percent\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eIOL power calculation\u003c/h2\u003e \u003cp\u003eThe IOL power was calculated with the BUII formula using all required values of the fellow eye (FE group). In addition, we used the BUII formula for the IOL calculation of the operated eye (OE), using all required values of the OE with only the AL of the fellow eye (AL-FE group) and (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) the AL of the OE after reattachment of the retina with silicone oil (OE group). Calculations were performed in October 2023 using the Barrett Universal II Formula V1.05 provided by the Asia-Pacific Association of Cataract and Refractive Surgeons (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://calc.apacrs.org/barrett_universal2105/\u003c/span\u003e\u003cspan address=\"https://calc.apacrs.org/barrett_universal2105/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e). We only used the Barrett Universal II formula in our study since it performed best in two recently published papers, both in eyes with silicone oil endotamponade and when using the axial length of the fellow eye\u003csup\u003e8,9\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eFor assessing the prediction error (PE) and absolute PE of the IOL power calculated with the BUII formula, we assessed the difference between the actual postoperative spherical equivalent refraction at the spectacle plane and the predicted refraction based on the implanted IOL power.\u003c/p\u003e \u003cp\u003ePE\u0026thinsp;=\u0026thinsp;predicted refraction \u0026ndash; actual postoperative refraction\u003c/p\u003e \u003cp\u003eAbsolute PE = | predicted refraction \u0026ndash; actual postoperative refraction |\u003c/p\u003e \u003cp\u003eIn the interpretation of the PE, a positive value means a hyperopic, and a negative value a myopic shift.\u003c/p\u003e \u003cp\u003eThe mean arithmetic prediction error (MPE), mean absolute prediction error (MAE), median absolute prediction error (MedAE), the maximum and minimum of these errors (range), as well as the percentage of eyes within \u0026plusmn;\u0026thinsp;0.50, \u0026plusmn;\u0026thinsp;1.00, and \u0026plusmn;\u0026thinsp;2.00 diopters (D) deviation from the target refraction were calculated.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eIn all eyes, the pseudonymized data was collected and entered manually into an Excel sheet (Version 14.7.7, Microsoft Corporation, Redmond, WA, USA). For statistical analysis, SPSS Software (Version 29.0; IBM Corporation, Armonk, NC, USA) was used. First, a Kolmogorov-Smirnov test was used to test for normal distribution. A Friedman test, and, if significantly different, a post hoc analysis with a Wilcoxon signed-rank test or paired t-test were performed (depending on distribution) to analyze differences in MPE and MedAE. To compare the percentage of PE within \u0026plusmn;\u0026thinsp;0.5D and \u0026plusmn;\u0026thinsp;1.0D, the Cochrane Q test was used. P-values below 0.05 were considered statistically significant. If needed, the p-values were corrected using the Bonferroni correction.\u003c/p\u003e \u003cp\u003eThe sample size estimation was performed using the G*Power 3.1 Software (Heinrich Heine University Duesseldorf, Germany). Based on a difference between the groups of 0.1 D with a standard deviation of 0.2 D at least 47 eyes were needed to reach power of at least 80%.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eIn this study, 79 eyes of 79 patients matched our inclusion criteria. 28 were female and 51 were males. The mean age was 59.32 years\u0026thinsp;\u0026plusmn;\u0026thinsp;9.62 (Range: 24\u0026ndash;82). The mean AL of the operated eye with SO fill after re-attachment of the retina was 25.27 mm\u0026thinsp;\u0026plusmn;\u0026thinsp;1.79 mm (Range: 22.06\u0026ndash;31.72). The mean AL of the fellow eye was 25.11 mm\u0026thinsp;\u0026plusmn;\u0026thinsp;1.81 mm (Range: 22.05\u0026ndash;32.08). The mean absolute difference of the AL of both eyes was 0.40 mm\u0026thinsp;\u0026plusmn;\u0026thinsp;0.50 mm (Range: 0.00\u0026ndash;2.76 mm), mean relative difference was 0.15 mm\u0026thinsp;\u0026plusmn;\u0026thinsp;0.62 mm (Range: -1.26 - +2.76 mm). The Pearson coefficient between the AL of the FE and the OE was 0.943 (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). In 23 patients, the AL was above 26.0 mm. Baseline characteristics of patients are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePatient Demographics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eStandard Deviation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMinimum\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMaximum\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (y)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e59.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e82\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAL OE (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e31.72\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAL FE (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e32.08\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKmean OE (D)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e38.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e45.77\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKmean FE (D)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e38.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e45.32\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eACD OE (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4.23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eACD FE (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.96\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLT OE (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.62\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLT FE (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.48\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIOL power (D)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePostop SE (D)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-1.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePostop VA (decimal)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;years; AL\u0026thinsp;=\u0026thinsp;Axial length, OE\u0026thinsp;=\u0026thinsp;operated eye; FE\u0026thinsp;=\u0026thinsp;Fellow eye; Kmean\u0026thinsp;=\u0026thinsp;mean keratometry; D\u0026thinsp;=\u0026thinsp;Diopters; ACD\u0026thinsp;=\u0026thinsp;Anterior chamber depth; LT\u0026thinsp;=\u0026thinsp;Lens thickness; IOL\u0026thinsp;=\u0026thinsp;Intraocular lens; Postop SE\u0026thinsp;=\u0026thinsp;Postoperative spherical equivalent; VA\u0026thinsp;=\u0026thinsp;Visual acuity\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe implanted monofocal IOLs were AAB00 (47 eyes, 59.5%), SN60AT (13 eyes, 16.5%), SN60WF (11 eyes, 13.9%), SA60AT (4 eyes, 5.1%), and MA60AC (4 eyes, 5.1%). The mean postoperative spherical equivalent was \u0026minus;\u0026thinsp;1.31 D\u0026thinsp;\u0026plusmn;\u0026thinsp;1.11. The mean IOL power was 18.46 D\u0026thinsp;\u0026plusmn;\u0026thinsp;4.09 (6.0\u0026ndash;25.0 D). The follow-up was at least one month in all patients.\u003c/p\u003e \u003cp\u003eMedAE was lowest in the OE group (0.41 D), followed by the FE group (1.00 D) and AL-FE group (1.02 D). Using Friedman\u0026rsquo;s test, the difference between the absolute error of the three groups was statistically significant (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Post-hoc analysis using the paired t-test with Bonferroni correction yielded a statistically significant difference between the absolute error (AE) comparing the OE group and AL-FE group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), as well as between the OE group and the FE group (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). However, when comparing the differences in the AE between the FE group and the AL-FE group, there was no statistically significant difference (p\u0026thinsp;=\u0026thinsp;0.960). MPE, MAE, and MedAE with standard deviation and range of all eyes are shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. No correlation was found between the AL of the OE and the absolute prediction error (Pearson coefficient = -0.091; p\u0026thinsp;=\u0026thinsp;0.424).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePostoperative Refractive Outcomes\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMPE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMAE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMedAE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMin\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eMax\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFE Group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-1.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.19\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFE-AL Group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.38\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOE Group\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.94\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003eMPE\u0026thinsp;=\u0026thinsp;Mean prediction error; MAE\u0026thinsp;=\u0026thinsp;Mean absolute error; MedAE\u0026thinsp;=\u0026thinsp;Median absolute error; SD\u0026thinsp;=\u0026thinsp;Standard deviation; FE\u0026thinsp;=\u0026thinsp;fellow eye; FE-AL\u0026thinsp;=\u0026thinsp;only the axial length of the fellow eye was used in combination with the measurable biometric data of the operated eye for IOL calculation; OE\u0026thinsp;=\u0026thinsp;operated eye\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eConsidering the number of eyes within \u0026plusmn;\u0026thinsp;0.50 D of the target refraction, the OE group performed best with 50 eyes (63.3%). In contrast, both the FE and AL-FE groups performed considerably less favorably, with 21 and 22 eyes (26.6% and 27.8%), respectively. Using the Cochrane Q test, a statistically significant difference was found between the OE and AL-FE groups, as well as between the OE and FE groups (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001 each). Comparison between the AL-FE and FE groups showed no statistically significant difference (p\u0026thinsp;=\u0026thinsp;0.712). Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the number of eyes within \u0026plusmn;\u0026thinsp;1.00 and \u0026plusmn;\u0026thinsp;2.00 D of the target refraction with likewise significantly more eyes in the OE group compared to the FE and AL-FE groups.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThe AL of the eye is the most crucial parameter in IOL calculation\u003csup\u003e10\u003c/sup\u003e. A 0.1 mm error in AL is equivalent to an error of about 0.27 D in the spectacle plane\u003csup\u003e11\u003c/sup\u003e. Therefore, high accuracy in the assessment of the AL is a necessity. For many years, in the clinical practice ultrasound was the only technique to measure the length of the eye. The accuracy of the AL measurement has improved considerably with the implementation of optical biometry using partial coherence interferometry (PCI)\u003csup\u003e12\u003c/sup\u003e. Despite technical progress, it is often not possible to determine the exact AL with the PCI integrated into the ocular biometer in eyes with macular-involving retinal detachment\u003csup\u003e6\u003c/sup\u003e. In cases of pre-existing lens opacities or cataracts, the surgeon may use the data of the fellow eye instead of ultrasound biometry which is known to be much less accurate\u003csup\u003e6\u003c/sup\u003e. Some studies report sufficient results for lens power calculation and prediction of refractive outcome when biometry of the fellow eye is used\u003csup\u003e13,14\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eIn the present study, we investigated whether using the entire IOL calculation of the fellow eye provides reliable results, or whether the axial length of the fellow eye in combination with the measurable biometric parameters of the affected eye induces a lower refractive error when the AL of the affected eye cannot be obtained. To the best of our knowledge, studies comparing the use of the AL of the fellow eye for the IOL calculation of the affected eye with the entire biometry of the fellow eye are rare.\u003c/p\u003e \u003cp\u003eOur results suggest that using the biometry of the FE (MedAE 1.00 D) for IOL calculations for macular-involving RD is as accurate as using only the AL of the fellow eye in combination with the measurable biometric parameters of the affected eye (MedAE 1.02 D). In our study, every second eye was within 1.0 D of its predicted refractive outcome.\u003c/p\u003e \u003cp\u003eComparing this with the outcome achieved when using the biometry of the operated eye after reattachment of the retina with SO fill, the IOL power predictability error is statistically and clinically significantly lower using a two-step procedure (MedAE 0.41 D) (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Furthermore, far more patients achieve an outcome within \u0026plusmn;\u0026thinsp;1.0 D of prediction (84.8%).\u003c/p\u003e \u003cp\u003eIn order to avoid postoperative anisometropia, it may be useful to ask the patient preoperatively whether there are differences between the refractive values of the two eyes and to rule out preoperative anisometropia. In our opinion, it is not advisable to use the biometric values of the fellow eye if there are major differences between the eyes, in order to avoid refractive surprises. We agreed with El-Khayat et al. who determined that it is possible to use the IOL calculation of the partner eye if the refraction values of both eyes are quite similar\u003csup\u003e14\u003c/sup\u003e. Manual entry of the axial length into the biometry device is, based on the results of the present study, not superior to using the entire IOL calculation of the fellow eye. A definite solution for this could be an intraoperative AL measurement after reattachment of the retina\u003csup\u003e15\u003c/sup\u003e. However, as long as this is not possible, the results of the fellow eye show a higher predictability compared to the calculation with an AL assessed with the macula detached, but as we could show in this and the previous publication, still a significantly worse result compared to the calculation with the AL in SO-filled eyes\u003csup\u003e8\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eIn addition to preoperative anisometropia, conditions that may preclude the use of biometry of the fellow eye include corneal disease, poor fixation, significant media opacity, and cataract and macular elevation/edema.\u003c/p\u003e \u003cp\u003eThe limitations of our study include the retrospective setting and the fact that different IOLs were included. However, the authors believe that the sample size is sufficient for this purpose. In addition, the IOL calculation of the fellow eye and the use of the axial length of the fellow eye were only performed theoretically, without corresponding implantation of the IOL in the affected eye. To best reflect the daily practice of most clinicians, we did not optimize the constants for the IOL calculation and decided to use proven constants. In our opinion, it was not necessary to optimize the constants as biometric data of the fellow eye was used. Based on the recommendations of Hoffer and Savini for reporting IOL calculation results, it shows that optimization of IOL constants is not indicated in highly specific and rare cases, which in our view would also apply to our study\u003csup\u003e16\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eHowever, when calculating lens replacement, accurate predictability can prevent anisometropic problems that could consecutively lead to lens surgery in the healthy eye, which could result in surgical risks such as retinal detachment or infection.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eOur results indicate no clinically relevant difference between using the entire IOL calculation of the fellow eye versus using only the axial length of the fellow eye in addition to the measurable biometric parameters of the affected eye for the determination of the IOL power. However, a two-step procedure using the AL of the operated eye after reattachment of the retina is still highly recommended for the best possible calculation of the IOL power.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e No funding was received for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest:\u003c/strong\u003e T. Kohnen:\u0026nbsp;Consultant and Research for Alcon/Novartis, J\u0026amp;J, Lensgen, Oculentis, Oculus, Presbia, Schwind, Zeiss. Consultant for Allergan, Bausch \u0026amp; Lomb, Geuder, Med Update, Santen, Staar, Thieme, Ziemer.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll other authors have no financial interests to disclose.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eData availability statement:\u0026nbsp;\u003c/strong\u003eAll data generated or analyzed during this study are included in this article. Further enquiries can be directed to the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval:\u003c/strong\u003e This study includes human participants and was approved by the ethics committee of the Goethe University Frankfurt (approval number: 2022-899). Before participating in the study, the participants gave their informed consent after been informed in detail.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHaimann MH, Burton TC, Brown CK. Epidemiology of retinal detachment. Arch Ophthalmol. 1982; 100(2): 289\u0026ndash;292.\u003c/li\u003e\n\u003cli\u003eSultan ZN, Agorogiannis EI, Iannetta D, Steel D, Sandinha T. Rhegmatogenous retinal detachment: a review of current practice in diagnosis and management. BMJ Open Ophth. 2020; 5(1): e000474.\u003c/li\u003e\n\u003cli\u003eBenson MD, Sia D, Seamone ME, Greve M, Hinz B, Tennant MTS, et al. Phacovitrectomy for primary rhegmatogenous retinal detachment repair: A retrospective review. Retina. 2021; 41(4): 753\u0026ndash;760.\u003c/li\u003e\n\u003cli\u003eVillegas VM, Gold AS, Latiff A, Wildner AC, Ehlies FJ, Murray TG. Phacovitrectomy. Dev Ophthalmol. 2014; 54: 102\u0026ndash;107.\u003c/li\u003e\n\u003cli\u003ePort AD, Nolan JG, Siegel NH, Chen X, Ness SD, Subramanian ML. Combined phaco-vitrectomy provides lower costs and greater area under the curve vision gains than sequential vitrectomy and phacoemulsification. Graefes Arch Clin Exp Ophthalmol. 2021; 259(1): 45\u0026ndash;52.\u003c/li\u003e\n\u003cli\u003eLiu R, Li H, Li Q. Differences in Axial Length and IOL Power Based on Alternative A-Scan or Fellow-Eye Biometry in Macula-Off Rhegmatogenous Retinal Detachment Eyes. Ophthalmol Ther. 2022; 11(1): 347\u0026ndash;354.\u003c/li\u003e\n\u003cli\u003eHoffmann EM, Aghayeva F, Wagner FM, Fiess A, Nagler M, M\u0026uuml;nzel T, et al. Intraocular pressure and its relation to ocular geometry: Results from the Gutenberg Health Study. Invest. Ophthalmol. Vis. Sci. 2022; 63(1): 40.\u003c/li\u003e\n\u003cli\u003eLwowski C, Kaiser KP, Bucur J, Schicho P, Kohnen T. Accuracy of using the axial length of the fellow eye for IOL calculation in retinal detachment eyes undergoing silicone oil removal. Br J Ophthalmol. 2023: bjo-2023-323581.\u003c/li\u003e\n\u003cli\u003eLwowski C, Miraka K, M\u0026uuml;ller M, Singh P, Koch F, Kohnen T. Intraocular lens calculation using 8 formulas in silicone oil-filled eyes undergoing silicone oil removal and phacoemulsification after retinal detachment. Am J Ophthalmol. 2022; 244: 166\u0026ndash;174.\u003c/li\u003e\n\u003cli\u003eLangenbucher A, Szentm\u0026aacute;ry N, Cayless A, R\u0026ouml;ggla V, Leydolt C, Wendelstein J, et al. Similarity of eyes in a cataractous population-How reliable is the biometry of the fellow eye for lens power calculation? PLoS One. 2022; 17(6): e0269709.\u003c/li\u003e\n\u003cli\u003eOlsen T. Calculation of intraocular lens power: a review. Acta Ophthalmol Scand. 2007; 85(5): 472\u0026ndash;485.\u003c/li\u003e\n\u003cli\u003eDrexler W, Findl O, Menapace R, Rainer G, Vass C, Hitzenberger CK, et al. Partial coherence interferometry: a novel approach to biometry in cataract surgery. Am J Ophthalmol. 1998; 126(4): 524\u0026ndash;534.\u003c/li\u003e\n\u003cli\u003eKnox Cartwright NE, Johnston RL, Jaycock PD, Tole DM, Sparrow JM. The Cataract National Dataset electronic multicentre audit of 55 567 operations: when should IOLMaster biometric measurements be rechecked? Eye. 2010; 24(5): 894\u0026ndash;900.\u003c/li\u003e\n\u003cli\u003eEl-Khayat AR, Brent AJ, Peart SAM, Chaudhuri PR. Accuracy of intraocular lens calculations based on fellow-eye biometry for phacovitrectomy for macula-off rhegmatogenous retinal detachments. Eye (Lond). 2019; 33(11): 1756\u0026ndash;1761.\u003c/li\u003e\n\u003cli\u003eMoussa G, Sachdev A, Mohite AA, Hero M, Ch\u0026rsquo;ng SW, Andreatta W. ASSESSING Refractive outcomes and accuracy of biometry in phacovitrectomy and sequential operations in patients with retinal detachment compared with routine cataract surgery. Retina. 2021; 41(8): 1605\u0026ndash;1611.\u003c/li\u003e\n\u003cli\u003eHoffer KJ, Savini G. Update on intraocular lens power calculation study protocols. Ophthalmology. 2021; 128(11): e115\u0026ndash;e120.\u003cbr\u003e \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"IOL calculation, phacovitrectomy, retinal detachment, fellow eye","lastPublishedDoi":"10.21203/rs.3.rs-3663811/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3663811/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003ePurpose\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTo evaluate whether the intraocular lens (IOL) calculation of the fellow eye (FE) can be used in eyes undergoing combined phacovitrectomy.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eIn this retrospective, consecutive case series, we enrolled patients who underwent silicone oil (SO) removal combined with phacoemulsification and IOL implantation at the Department of Ophthalmology, Goethe University, Frankfurt, Germany. Preoperative examinations included biometry using the IOL Master 700 (Carl Zeiss Meditec AG, Jena, Germany). We used the IOL calculation of the FE (FE group) to calculate the prediction error compared with the IOL calculation using only the axial length of the FE (AL-FE group), as well as using the axial length (AL) of the operated eye (OE group) in addition to the measurable biometric parameters. For the IOL calculation, the Barrett Universal II formula was used. We compared the mean prediction error (MPE) as well as the mean (MAE) and median absolute prediction error (MedAE) with each other. In addition, the number of eyes with \u0026plusmn;\u0026thinsp;0.50, \u0026plusmn;\u0026thinsp;1.00, and \u0026plusmn;\u0026thinsp;2.00 diopters (D) deviation from the target refraction was compared.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eIn total, 79 eyes of 79 patients met our inclusion criteria. MedAE was lowest in the OE group (0.41 D), followed by FE group (1.00 D) and AL-FE group (1.02 D). Comparison between the AL-FE and FE groups showed no statistically significant difference (p\u0026thinsp;=\u0026thinsp;0.712). Comparing eyes within \u0026plusmn;\u0026thinsp;0.50 D of the target refraction, the OE group (50 eyes, 63.3%) performed best, followed by the AL-FE group (22 eyes, 27.8%) and the FE group (21 eyes, 26.6%).\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e \u003cp\u003eOur results indicate no clinically relevant difference between using the IOL calculation of the fellow eye versus using only the axial length of the fellow eye in addition to the measurable parameters for the IOL calculation. A two-step procedure should always be strived for.\u003c/p\u003e","manuscriptTitle":"Fellow Eye Data for IOL Calculation in Eyes Undergoing Combined Phacovitrectomy","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-09 19:50:07","doi":"10.21203/rs.3.rs-3663811/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f2f04369-8cfa-4a7c-b94b-2f5e8ac21db5","owner":[],"postedDate":"January 9th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-02-21T13:15:22+00:00","versionOfRecord":[],"versionCreatedAt":"2024-01-09 19:50:07","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3663811","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3663811","identity":"rs-3663811","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}