Refractive changes after vitrectomy and phacovitrectomy for macular hole and epiretinal membrane

Refractive outcome in combined phacovitrectomy: Anterior segment changes and corrective factor for IOL power calculation improvement

PURPOSE

To analyze differences in refractive outcome Δ (difference between postoperative and expected refractive error) and in anterior segment changes between cataract surgery patients and combined phacovitrectomy patients. We also aimed to provide a corrective formula allowing to minimise the refractive outcome Δ in combined surgery patients.

METHODS

Candidates for phacoemulsification and combined phacovitrectomy (respectively PHACO and COMBINED groups) were prospectively enrolled in two specialised centres. Patients underwent best corrected visual acuity (BCVA) assessment, ultra-high speed anterior segment optical coherence tomography (OCT), gonioscopy, retinal OCT, slit lamp examination and biometry at baseline, 6 weeks postoperatively and 3 months postoperatively.

RESULTS

No differences in refractive Δ, refractive error and anterior segment parameters were noted between PHACO and COMBINED group (109 and 110 patients respectively) at 6 weeks. At 3 months, COMBINED group showed a spherical equivalent of -0.29 ± 0.10 D versus -0.03 ± 0.15 D in PHACO group (p = 0.023). COMBINED group showed a significantly higher Crystalline Lens Rise (CLR), angle-to-angle (ATA) and anterior chamber width (ACW) and a significantly lower anterior chamber depth (ACD) and refractive Δ with all 4 considered formulas at 3 months. For IOL power lower than 15, a hyperopic shift was observed instead.

CONCLUSIONS

Anterior segment OCT suggests anterior displacement of the effective lens position in patients undergoing phacovitrectomy. A corrective formula can be applied to IOL power calculation to minimize undesired refractive error.

ACCURACY OF NEW INTRAOCULAR LENS CALCULATION FORMULAE IN EYES UNDERGOING SILICONE OIL REMOVAL/PARS PLANA VITRECTOMY-CATARACT SURGERY

PURPOSE

To investigate the performance of novel intraocular lens calculation formulae (Barrett Universal II, Emmetropia Verifying Optical, and Kane) and conventional formulae (Haigis, Hoffer Q, Holladay 1, and Sanders-Retzlaff-Kraff/T [SRK/T]) in patients who underwent pars plana vitrectomy or silicone oil removal combined with cataract surgery.

METHODS

In total, 301 eyes from 301 patients who underwent pars plana vitrectomy/silicone oil removal with concomitant cataract surgery were enrolled and divided into the following four groups according to preoperative diagnosis: silicone oil-filled eyes after pars plana vitrectomy, epiretinal membrane, primary retinal detachment, and macular hole.

RESULTS

Barrett Universal II exhibited the smallest mean absolute error (0.65 diopters [D]) and median absolute error (0.39 D) in total. In patients with primary retinal detachment, each formula exhibited the worst refractive outcomes in diverse vitreoretinal pathologies ( P < 0.01), and no difference in accuracy between the seven formulas was observed ( P = 0.075). For long eyes, the second linear (Wang-Koch 2) version of the Wang-Koch adjustment significantly reduced the median absolute error for Holladay 1 and SRK/T ( P < 0.001 and P = 0.019).

CONCLUSION

In combined surgery, both new and conventional formulas using the second linear version of the Wang-Koch 2 adjustment demonstrated satisfactory performance, with Barrett Universal II exhibiting the best overall performance. However, in patients with primary retinal detachment, all seven formulas showed less favorable performance.

Postoperative Refractive Outcomes of Biometric Formulas in Phacovitrectomy with Gas Tamponade

PURPOSE

To investigate the refractive accuracy of intraocular lens (IOL) power calculation for biometric formulas in phacovitrectomy.

METHODS

This retrospective study included 357 eyes of 357 patients who underwent phacovitrectomy using four commonly available IOL power formulas: Hoffer Q (87 eyes), Holladay 1 (78 eyes), Holladay 2 (91 eyes), and SRK/T (101 eyes). The mean refractive error (ME) and the mean absolute refractive error (MAE) were calculated based on the predicted postoperative refraction error, and they were compared using analysis of variance test. Subjects were divided into high myopic eyes (axial length, ≥26 mm) and nonhigh myopic eyes (axial length, <26 mm).

RESULTS

The ME and the MAE after phacovitrectomy did not show a significant difference among the four IOL power formulas (p = 0.546 and p = 0.495, respectively). There was no significant statistical difference in formulas when the eyes were grouped into high myopia and nonhigh myopia (ME: p = 0.526 and p = 0.482, respectively; MAE: p = 0.715 and p = 0.627, respectively). The ME showed myopic shift in all formulas regardless of IOL formula used. The ME showed greater myopic shift in high myopia group than nonhigh myopia group in all formulas.

CONCLUSIONS

Our study did not find evidence for superiority of any formula in phacovitrectomy. However, in phacovitrectomy, possible myopic shift should be considered for IOL power calculation. Especially, in phacovitrecotmy in patients with high myopia, more myopic shift should be considered when selecting IOL.

Influence of endotamponade on anterior chamber depth and refractive outcome after combined phacovitrectomy: case-control study

PURPOSE

To compare the changes in the anterior chamber depth (ACD) and in the refractive outcomes after combined phacovitrectomy with respect to the endotamponade (balanced salt solution, air, sulfur hexafluoride [SF 6 , gas]).

SETTING

Department of Ophthalmology, University Hospital Ulm, Ulm, Germany.

DESIGN

Retrospective, longitudinal case-control study.

METHODS

160 eyes of 160 patients were included in the study. 120 eyes underwent phacoemulsification with in-the-bag implantation combined with vitrectomy and were divided into 3 groups according to tamponade (balanced salt solution, air, gas). 40 control eyes with cataract surgery only were included. Further inclusion criteria were uneventful surgery, no postoperative complications and absence of corneal pathology. Endpoints were ACD as measured by swept-source optical coherence tomography-based biometry (IOLMaster 700) preoperatively, 1 to 2 days and 6 weeks postoperatively and refractive prediction error (PE) using the Barrett and Haigis formulas.

RESULTS

Within the first 2 days after surgery the ACD was shallower in the eyes left with gas or air tamponade, when compared with balanced salt solution or cataract surgery alone ( P < .001). This effect diminished 6 weeks later, and all eyes reached comparable ACD ( P = .396). The refractive PE was slightly, but statistically significantly higher in the gas group when compared with cataract surgery alone ( P = .012 for Barrett, P = .006 for Haigis).

CONCLUSIONS

The resulting ACD after combined phacovitrectomy was independent of the tamponade used, but a gas-tamponade was associated with a higher refractive PE.

Combined versus Sequential Pars Plana Vitrectomy and Phacoemulsification for Macular Hole and Epiretinal Membrane - A Systematic Review and Meta-Analysis

TOPIC

To compare the efficacy and safety between combined and sequential pars plana vitrectomy and phacoemulsification for macular hole (MH) and epiretinal membrane (ERM).

CLINICAL RELEVANCE

The standard of care for MH and ERM is vitrectomy, which increases risk of developing cataract. Combined phacovitrectomy eliminates the need for a second surgery.

METHODS

Ovid MEDLINE, EMBASE, and Cochrane CENTRAL were searched in May 2022 for all articles comparing combined versus sequential phacovitrectomy for MH and/or ERM. The primary outcome was mean best-corrected visual acuity (BCVA) at 12-months follow-up. Meta-analysis was conducted using a random effects model. Risk of bias was assessed using the Cochrane RoB 2 tool for randomized controlled trials (RCTs) and ROBINS-I tool for observational studies. (PROSPERO, registration number, CRD42021257452) RESULTS: Of the 6470 studies found, 2 RCTs and 8 non-randomized retrospective comparative studies were identified. Total eyes for combined and sequential groups were 435 and 420, respectively. Meta-analysis suggested no significant difference between combined and sequential surgery for 12-month BCVA (combined = 0.38 logMAR, sequential = 0.36 logMAR; mean difference (MD) = +0.02 logMAR; 95% CI = -0.04 to 0.08; p = 0.51, I² = 0%, n = 4 studies, 398 participants), as well as absolute refractive error (p = 0.76, I² = 97%, n = 4 studies, 289 participants), risk of myopia (p = 0.15, I² = 66%, n = 2 studies, 148 participants), MH non-closure (p = 0.57, I² = 48%, n = 4 studies, 321 participants), cystoid macular edema (p = 0.15, I² = 0%, n = 6 studies, 526 participants), high intraocular pressure (p = 0.09, I² = 0%, n = 2 studies, 161 participants), posterior capsule opacification (p = 0.46, I² = 0%, n = 2 studies, 161 participants), posterior capsule rupture (p = 0.41, I² = 0%, n = 5 studies, 455 participants) and retinal detachment (p = 0.67, I² = 0%, n = 6 studies, 545 participants).

CONCLUSION

No significant difference was detected between combined and sequential surgeries for visual outcomes, refractive outcomes, or complications. Given that most studies were retrospective and contained a high risk-of-bias, future high-quality RCTs are warranted.

Assessment of Risk Factors Affecting Refractive Outcomes after Phacovitrectomy for Epiretinal Membrane

PURPOSE

To investigate factors associated with refractive outcomes after phacovitrectomy for epiretinal membrane (ERM).

METHODS

Retrospective review of patients undergoing phacovitrectomy for ERM was done. The main outcome measure was predictive refraction error (PE), defined as observed refraction error - target refraction error, calculated by the SRK/T, Haigis, and SRK II formulae. PE was measured at postoperative 1, 3, and 6 months. Simple and multiple linear regression analysis were used to evaluate factors associated with PE.

RESULTS

A total of 53 eyes of 53 patients were included. The mean PEs at postoperative 1, 3, and 6 months were all negative, implying myopic shift in all patients regardless of the intraocular lens formula used. Haigis formula showed the least myopic shift among the three formulae (p = 0.001, Friedman test). There was no significant difference in PE depending on preoperative central macular thickness (CMT) in subgroup analysis. On stepwise multiple linear regression analysis, ERM etiology (β = 0.759, p = 0.004, SRK/T formula; β = 0.733, p = 0.008, Haigis formula; β = 0.933, p < 0.001, SRK II formula), preoperative anterior chamber depth (β = -0.662, p = 0.013, Haigis formula; β = -0.747, p = 0.003, SRK II formula), and decrease of CMT (β = -0.003, p = 0.025, SRK/T formula) were significantly associated with PE at postoperative 6 months.

CONCLUSIONS

Myopic shift in PE was observed after combined phacovitrectomy for epiretinal membrane. ERM etiology, preoperative anterior chamber depth, and decrease of CMT were significantly associated with PE at postoperative 6 months. There was no difference in PE after surgery between the two groups defined by CMT (≥500 and <500 μm).

The Postvitrectomy Cataract

To review the recent literature regarding risk factors for cataract formation after vitrectomy, the challenges and management strategies for anterior segment surgeons when facing post-vitrectomy cataract surgery, and the visual outcomes of patients undergoing post-vitrectomy cataract surgery. Cataract surgery after vitrectomy can be safely performed to significantly improve the visual outcome in most post-vitrectomy patients, although final visual acuity is primarily limited by the patient’s underlying vitreoretinal pathology.

Influence of combined phacovitrectomy without tamponade on intraocular lens displacement and postoperative refraction

PURPOSE

To compare phacoemulsification versus phacovitrectomy regarding postoperative intraocular lens (IOL) shift and refraction.

METHODS

This prospective bilateral comparison study included 40 eyes of 20 patients. Inclusion criteria were combined phacovitrectomy without gas/air tamponade in one eye and cataract surgery in the contralateral eye with implantation of the same IOL. Postoperative anterior chamber depth (ACD) was compared between both groups 1-5 hr, 1 day and 8 weeks after surgery. Postoperative refraction was compared after 8 weeks using the Holladay I, HofferQ, SRK/T, Haigis and Barrett formulae.

RESULTS

There were no intergroup differences in ACD (8 weeks: 0.02 mm absolute difference, SD 0.22, range -0.36 to 0.65, p = 0.401), mean absolute refractive error (8 weeks: Holladay I p = 0.452; HofferQ p = 0.475; SRK/T p = 0.498; Haigis p = 0.869; and Barrett p = 0.352) or percentages within the 0.5 D and 1.0 D range at any time-point. All formulae were optimized for the phacovitrectomy and the cataract groups. There was no correlation of macular thickness change and refractive error (cataract group r²  = -0.13, p = 0.58; phacovitrectomy group r²  = -0.10, p = 0.68).

CONCLUSION

Combined phacovitrectomy without air/ gas tamponade caused neither ACD displacement nor refractive shifts compared to phacoemulsification alone. Surgically induced macular thickness change had no significant influence on postoperative refraction in this study. All five IOL formulae showed comparable postoperative refractive outcomes.

Corneal shape changes after vitreoretinal surgery with fluid-gas exchange

To investigate changes in the corneal shape caused by fluid-gas exchange after vitrectomy.This retrospective case-control study included 43 eyes that underwent a combination of cataract surgery and vitrectomy. The corneal shape was measured using anterior segment optical coherence tomography CASIA2. The corneal shape measurements were performed preoperatively, 1 day, 1 week, 1 month, and 3 months after surgery. After calculating the real K value from the actual measured values of the posterior shape of the corneal refracting power and the single posterior corneal refracting power value, Fourier analysis values were examined. Fluid-gas exchange was performed in 23 eyes (gas group), while it was not performed in 20 eyes (nongas group).There was a significant increase in the real K value in the regular and asymmetry components (0.61 ± 0.36, 0.82 ± 0.64) in the gas group only on the first day after surgery (Steel-Dwass test; P < .05). There was also a significant increase in the real K value in the higher-order irregular astigmatism components (Steel-Dwass test; P < .05) for longer periods in the gas versus the nongas group. The shape of the posterior cornea increased in all components in the gas group on the first day after surgery (spherical power -6.35 ± 0.20, regular astigmatism 0.32 ± 0.12, asymmetry 0.22 ± 0.13, and higher-order irregular astigmatism 0.12 ± 0.05, Steel-Dwass test; P < .05).Postoperative changes caused by surgical invasion in the corneal shape appeared to be greater in the gas versus the nongas group, in addition to affecting the time periods of the postoperative corneal shape changes.

Evaluation of the effects of vitrectomy with primary epiretinal membrane peel on optical quality using double-pass aberrometry

INTRODUCTION

We performed a prospective, single-center, cohort study in order to evaluate the effects of vitrectomy with epiretinal membrane (ERM) peel on optical quality in patients with primary ERM.

METHODS

Thirty patients treated for primary ERM by vitrectomy with ERM peel were included from our tertiary university hospital ophthalmology department. The main study outcome was variation in optical quality parameters measured using the HD Analyzer™ between pre-operative and two-month post-operative evaluations in operated eyes. Optical quality parameters comprised point spread function (PSF) width at 10% and 50%, objective scatter index (OSI), and modulation transfer function (MTF) cutoff. Contralateral non-operated eyes were used as an internal control for measurement reproducibility.

RESULTS

Mean PSF width at 10% (42.22 vs 27.37 arc/min; p = 0.0002) and mean OSI (3.32 vs 2.32; p = 0.0003) were significantly improved between pre- versus post-operative evaluations. Mean PSF width at 50% and mean MTF cutoff showed no changes. Subgroup analysis according to crystalline lens status gave similar results demonstrating that improvements in mean PSF width at 10% and OSI were not lens-related. Non-operated eyes showed no changes in any of the parameters analyzed.

CONCLUSION

Reduced light scattering measured by OSI indicates improved optical quality following vitrectomy with ERM peel among patients with primary ERM. OSI measurement could thus be a new parameter of interest in the pre-operative assessment of primary ERM and other pre-vitrectomy assessments.

Visual outcomes after vitrectomy for epiretinal membrane in pseudophakic eyes with a diffractive trifocal intraocular lens: a retrospective cohort study

BACKGROUND

Diffractive intraocular lenses (IOLs) could affect visual acuity in patients with macular pathologies such as epiretinal membrane (ERM) and could influence the results of pars plana vitrectomy (PPV) for ERM removal in pseudophakic eyes with these IOLs. The aim of this study is to evaluate the effect on visual outcomes of a diffractive trifocal IOL in PPV for ERM peeling.

METHODS

This is a retrospective cohort study on 20 eyes with a single model of trifocal IOL that underwent PPV for removal of ERM between January 2015 and September 2018 in our clinics. Follow up was at least 1 year. Primary outcome measure was mean change in visual acuity. Secondary outcome measures were mean change in central macular thickness (CMT), recovery of the external retinal layers, and change in spherical equivalent (SE).

RESULTS

Mean corrected distance visual acuity (CDVA) was 0.03 ± 0.03 logMAR after phacoemulsification; this worsened to 0.23 ± 0.10 logMAR with ERM, improving to 0.10 ± 0.04 log MAR 12 months after PPV (p = 0.001). Mean uncorrected near visual acuity (UNVA) was Jaeger 2.62 ± 0.51 after lensectomy. This worsened to Jaeger 5.46 ± 1.67 with ERM and improved to the initial Jaeger 2.69 ± 0.84 after PPV (p = 0.005). CMT decreased significantly, from 380.15 ± 60.50 μm with the ERM to 313.70 ± 36.98 μm after PPV. Mean SE after lensectomy was - 0.18 ± 0.38 D, which minimally changed to - 0.18 ± 0.47 D after PPV (p = 0.99). The only complication recorded after PPV was a case of cystoid macular edema. No difficulties in visualization due to IOL design were reported during PPV.

CONCLUSION

PPV for ERM in eyes with this trifocal IOL seems to be safe and effective, and allows recovery of the loss of UNVA.

Scleral Fixation of a Hydrophobic Acrylic Intraocular Lens with Eyelets Using 8-0 Polypropylene Suture

Purpose

To report clinical outcomes of a scleral fixation technique of a hydrophobic acrylic intraocular lens with eyelets using 8-0 polypropylene suture.

Methods

Nine eyes of nine patients who underwent combined pars plana vitrectomy and sclera fixation of an intraocular lens using this technique were analyzed.

Results

The mean follow-up period was 7.11 months (range, 6–12 months), and there was a significant visual improvement at 6 months after surgery. The mean logarithm of the minimum angle of the resolution changed from 0.54 at baseline to 0.29 at postoperative 6 months (p = 0.016). The mean postoperative spherical equivalent at 6 months was −0.90 ± 0.90 diopters, and the mean predictive error was −0.49 ± 0.62 diopters.

Conclusions

Postoperative visual and refractive outcomes were favorable, and the positions of intraocular lenses were well centered in all cases. This technique could be a useful alternative for surgeons without easy access to Gore-Tex suture.

COMBINED PHACOEMULSIFICATION SURGERY WITH MULTIFOCAL INTRAOCULAR LENS IMPLANTATION AND PARS PLANA VITRECTOMY FOR SYMPTOMATIC VITREOUS OPACITIES

PURPOSE

To report surgical outcomes of combined vitrectomy for vitreous floaters and phacoemulsification surgery with multifocal intraocular lens implantation.

METHODS

Retrospective, interventional, noncomparative case series of five eyes from five patients who underwent same-day combined phacoemulsification surgeries with apodized, diffractive multifocal intraocular lens implantation for cataract and pars plana vitrectomy for symptomatic vitreous opacities, that is, floaters. Primary outcomes were distance and near visual acuities, and resolution of symptoms. Secondary outcomes included intraocular pressure, refractive outcomes, and surgical complications.

RESULTS

Mean logarithm of the minimum angle of resolution glare distance visual acuity improved from 0.36 (best-corrected Snellen 20/47) preoperatively to an uncorrected distance visual acuity of 0.05 (Snellen 20/23) at 6 months postoperatively (P = 0.042). All but one patient achieved multifocality with a near visual acuity of J2 or better. All patients noted subjective improvement in symptoms from floaters postoperatively. Mean intraocular pressure remained stable during follow-up. Two eyes ultimately required YAG capsulotomies for symptomatic posterior capsular opacification, one of which additionally received LASEK for refractive correction.

CONCLUSION

Multifocality and improvement in symptoms from symptomatic vitreous opacities were observed in this pilot series of carefully selected patients who underwent combined phacovitrectomy with multifocal intraocular lens implantation. A high rate of retinal tears was found in these patients. Appropriate caution should be taken in preoperative assessment and patient selection for the combined procedure.

Association of Aberrant Posterior Vitreous Detachment and Pathologic Tractional Forces With Myopic Macular Degeneration

Purpose

The purpose of this study was to assess whether the tractional elements of pathologic myopia (PM; e.g. myopic traction maculopathy [MTM], posterior staphyloma [PS], and aberrant posterior vitreous detachment [PVD]) are associated with myopic macular degeneration (MMD) independent of age and axial length, among highly myopic (HM) eyes.

Methods

One hundred twenty-nine individuals with 239 HM eyes from the Myopic and Pathologic Eyes in Singapore (MyoPES) cohort underwent ocular biometry, fundus photography, swept-source optical coherence tomography, and ocular B-scan ultrasound. Images were analyzed for PVD grade, and presence of MTM, PS, and MMD. The χ² test was done to determine the difference in prevalence of MMD between eyes with and without PVD, PS, and MTM. Multivariate probit regression analyses were performed to ascertain the relationship between the potential predictors (PVD, PS, and MTM) and outcome variable (MMD), after accounting for possible confounders (e.g. age and axial length). Marginal effects were reported.

Results

Controlling for potential confounders, eyes with MTM have a 29.92 percentage point higher likelihood of having MMD (P = 0.003), and eyes with PS have a 25.72 percentage point higher likelihood of having MMD (P = 0.002). The likelihood of MMD increases by 10.61 percentage points per 1 mm increase in axial length (P < 0.001). Subanalysis revealed that eyes with incomplete PVD have a 22.54 percentage point higher likelihood of having MMD than eyes with early PVD (P = 0.04).

Conclusions

Our study demonstrated an association between tractional (MTM, PS, and persistently incomplete PVD) and degenerative elements of PM independent of age and axial length. These data provide further insights into the pathogenesis of MMD.

The Role of Anterior Chamber Depth on Post-operative Refractive Error After Phacovitrectomy

Purpose

To investigate the effect of phacovitrectomy on the post-operative anterior chamber depth (ACD) and refractive outcomes, and to analyze the potential differences between vitreous filling with BSS, air and gas.

Methods

Patients who underwent phacovitrectomy were included in this study and invited for repeated post-operative examination including refraction and biometry at least 3 months after the surgery. Data retrieved included demographic information, indication for phacovitrectomy, surgical details, type of vitreous filling (BSS, air or gas), pre-operative and post-operative biometric data including K-readings, axial length (AL), and ACD, as well as spherical equivalent (SE) values of the target and final refraction.

Results

Forty-three eyes of 43 patients were included in this study, including 10 eyes filled with BSS, 18 with air and 15 with gas. The mean difference between the final measured spherical equivalent (SE) and the SE of the intended target refraction was 0.61±0.68 D (p = 0.019). Only 58.1% of eyes had a final SE within ±0.5D of the target refraction. Following surgery, AL remained unchanged, while mean pre-operative ACD increased significantly from 3.11±0.34 mm to 4.77±0.47 mm (p < 0.001). There was no difference in refractive error between the vitreous fillings and no correlation with AL or ACD.

Conclusions

Phacovitrectomy is associated with lower accuracy of post-operative refraction compared to cataract surgery. This may be attributed to a significant change in ACD, influencing the effective lens position of the IOL, and may require adjustment of the pre-operative calculations.

Refractive outcomes of 8 biometric formulas in combined phacovitrectomy with internal limiting membrane peeling for epiretinal membrane

PURPOSE

To investigate the accuracy of 8 different biometric formulas in combined phacovitrectomy and the effect of constant optimization on refractive outcome.

SETTING

Ludwig-Maximilians-University, Munich, Germany.

DESIGN

Retrospective observational case series.

METHODS

In this single-center study, patients with cataract and epiretinal membrane who underwent combined phacovitrectomy with internal limiting membrane peeling (Group B) and axial length-matched patients who underwent phacoemulsification (Group A) were included. In Group C, optimized constants from Group A were applied in patients of Group B. One eye of each patient was included. Main outcome measures after constant optimization for each biometric formula were refractive prediction error (PE), mean absolute error (MAE), and percentages of eyes with a PE within ±0.25 diopters (D), ±0.5 D, and ±1.0 D.

RESULTS

The study comprised 128 patients. For all formulas in Group A and Group B, refractive PE was 0.000 (P = .964 and P = .967, respectively). For formulas Barrett, Haigis, Hill, Hoffer Q, Holladay 1, Holladay 2, Kane, and SRK-T, refractive PE was -0.147, -0.204, -0.180, -0.212, -0.180, -0.178, -0.153, and -0.159, respectively, in Group C (P = .569); MAE was 0.346, 0.375, 0.382, 0.379, 0.355, 0.377, 0.318, and 0.364, respectively, in Group A (P = .286); 0.402, 0.422, 0.417, 0.427, 0.417, 0.402, 0.370, and 0.401, respectively, in Group B (P = .364); and 0.401, 0.424, 0.419, 0.444, 0.424, 0.404, 0.391, and 0.422, respectively, in Group C (P = .767). Effect of constant optimization in phacovitrectomy was statistically significant for all formulas (P < .001 for each formula).

CONCLUSIONS

No statistically significant difference was observed between the biometric formulas with regard to PE and MAE. However, in terms of phacovitrectomy, constant optimization should be considered for individual intraocular lens power calculations attributable to myopic shift.

Refractive change and optical biometry dynamics after 25-gauge vitrectomy in pseudophakic eyes

OBJECTIVE

To investigate the refractive change and optical biometry dynamics after 25-gauge vitrectomy without gas tamponade for macular pathology in pseudophakic eyes.

DESIGN

A prospective observational case series.

PARTICIPANTS

Patients with pseudophakic eyes who were scheduled for vitrectomy owing to macular pathology by an experienced surgeon (T.S.) at the Hayashi Eye Hospital between March 2019 and February 2020.

METHODS

The primary endpoint was the change in manifest refraction spherical equivalent (MRSE) between baseline (preoperatively) and 3 months postoperatively. The secondary endpoint was the change in optical biometry parameters obtained by swept-source optical coherence tomography-based biometers between baseline and 3 months postoperatively. Optical biometry parameters included corneal curvature and axial length, evaluated by the IOLMaster 700, and intraocular lens position-that is, lens decentration, lens tilt, and aqueous depth (AQD)-evaluated by the CASIA2.

RESULTS

Thirty-four eyes of 34 patients were enrolled. The mean MRSE values at baseline and 3 months postoperatively were -0.70 ± 1.21 diopter (D) and -0.82 ± 1.27 D, respectively, showing a significant myopic shift of -0.12 ± 0.41 D postoperatively (p = 0.043). There was no significant difference between the pre- and postoperative values of the optical biometry parameters, except for the AQD (4.28 ± 0.34 mm vs 4.27 ± 0.34 mm; p = 0.019).

CONCLUSIONS

The results suggest that replacing the vitreous by the aqueous during vitrectomy induces an average myopic shift of -0.12 D.

Refractive Outcomes and Anterior Chamber Depth after Cataract Surgery in Eyes with and without Previous Pars Plana Vitrectomy

Purpose: To compare the differences in refractive outcome and anterior chamber depth (ACD) after phacoemulsification between eyes with and without previous pars plana vitrectomy (PPV).Materials and Methods: Patients who had significant cataracts after PPV were included in the study group, and patients with a matched axial length (AL) who had cataracts without PPV were selected as the control group. The performance of new generation intraocular lens (IOL) power calculation formulas (Barrett Universal II, Kane, Ladas Super formulas), and the traditional formulas (SRK/T, Holladay 1, Hoffer Q, Haigis) with and without the Wang-Koch (WK) AL adjustment were compared between the two groups. The postoperative ACD was measured using the Scheimpflug imaging system with manual correction at least three months after surgery. Results: In total, there were 193 eyes from 193 patients in each group. The mean prediction errors (MEs) of the new generation formulas had no significant systemic bias in the study group; the hyperopic shift was displayed in the traditional formulas for eyes with AL > 26mm. However, the difference of MEs between the two groups among all the formulas were not significant. The absolute prediction error (MAE) and median prediction error (Med AE) in the study group were larger than those in the control group among all the formulas. The postoperative ACD of the study group was deeper but not significant than that of the control group. Conclusions: There was no refractive shift in vitrectomized eyes compared with non-vitrectomized eyes no matter in new generation formulas or traditional vergence formulas. The prediction error among all the formulas in vitrectomized eyes were significantly higher than those in non-vitrectomized eyes. The ACD after phacoemulsification in vitrectomized eyes was not significantly different from non-vitrectomized eyes.

POSTOPERATIVE MOVEMENT OF THE FOVEA AFTER SUCCESSFUL SURGERY IN PATIENTS WITH IDIOPATHIC EPIRETINAL MEMBRANES

PURPOSE

To evaluate the change in the fovea's postoperative location after successful pars plana vitrectomy with combined epiretinal and internal limiting membrane peeling in patients with idiopathic epiretinal membranes (iERMs).

METHODS

In this prospective study 32 eyes of 32 patients with iERMs were followed from baseline before until 3 months after surgery. Study measures included 4-m Early Treatment Diabetic Retinopathy Study best-corrected visual acuity, enhanced-depth imaging-optical coherence tomography, and intraoperative fundus photographs. Foveal movement was assessed by measuring the change in the papillofoveal distance (∆PFD).

RESULTS

Mean ∆PFD in the study eye was -124 µm (±138) and -272 µm (±213) one day and 3 months after surgery, respectively. Mean ∆PFD after 3 months was greater in the study than in the fellow eye (P < 0.001). ∆PFD at Month 3 did not correlate with the internal limiting membrane area peeled (P = 0.78).

CONCLUSION

Foveal movement starts immediately after surgery and causes a statistically significant reduction in PFD after uneventful macular pucker surgery. ∆PFD correlates statistically significantly with baseline best-corrected visual acuity and baseline central retinal thickness. The internal limiting membrane peeling size had no significant effect on the amount of postoperative foveal dislocation.

Refractive outcomes after vitrectomy combined with phacoemulsification of idiopathic macular holes

AIM

To report the refractive outcomes after vitrectomy combined with phacoemulsification and intraocular lens (IOL) implantation (phaco-vitrectomy) in idiopathic macular holes (IMH).

METHODS

A total of 56 eyes with IMH (IMH group) that underwent phaco-vitrectomy and 44 eyes with age-related cataract (ARC group) that underwent cataract surgery were retrospectively reviewed. The best corrective visual acuity (BCVA), predicted refractive error (PRE), actual refractive error (ARE), axial length (AL), were measured in both groups before and 6mo after operation. The power calculation of IOL and the predicted refractive error (PRE) were calculated according to the SRK/T formula. The difference of PRE and ARE between the two groups were compared and analyzed.

RESULTS

In the IMH group, the diameters of macular holes were 271.73±75.85 µm, the closure rate was 100%. The pre- and post-operative BCVA were 0.80±0.35 and 0.40±0.35 logMAR. The PRE of A-ultrasound and IOL Master in the IMH group was -0.27±0.25 and 0.10±0.66 D. The postoperative mean absolute prediction error (MAE) was observed to be 0.58±0.65 and 0.53±0.37 D in the IOL Master and A-ultrasound (P=0.758). The PRE and ARE of the IMH group were 0.10±0.66 D and -0.19±0.64 D (P=0.102). The PRE and ARE of the ARC group was -0.43±0.95 and -0.31±0.93 D (P=0.383). The difference between PRE and ARE was -0.33±0.81 and 0.09±0.64 D in the IMH and ARC groups (P=0.021). The proportion of myopic shift was 67.9% in the IMH group and 27.3% in the ARC group (P=0.004).

CONCLUSION

The myopic shift can be observed in patients with IMH after phaco-vitrectomy.

Biometric refractive error after cataract and retina surgery: a systematic review and a benchmark proposal

PURPOSE

To systematically review studies on refractive error after phacovitrectomy and phacoemulsification and to investigate factors associated with larger error.

MATERIALS AND METHODS

A literature search was performed using PUBMED and EMBASE until May 2020. The articles were included in the study if they reported data about refractive error as the difference in spherical equivalent between actual vs. target refraction in patients who underwent phacovitrectomy and phacoemulsification according to the type of biometry (ultrasound or optical). An inverse variance meta-analysis technique was used to pool errors; standard deviations (SDs), which are an expression of random error, were reported descriptively as median and range of the 95% coefficient of reproducibility (95% CR: 1.96 SD).

RESULTS

Twenty-one studies (197,353 eyes) were included. The mean error obtained using optical biometry was negligible for phacoemulsification (0.04 D, 95% CI: -0.04 to 0.12; 8 studies, 587 eyes) and was consistent with larger datasets using mixed biometric methods (0.02, 95% CI -0.07 to 0.04; 5 studies, 194,522 eyes). A trend towards hyperopia was found with ultrasound biometry after phacoemulsification (+0.21 D, 0.00-0.42 D; 7 studies, 394 eyes). Mean error after phacovitrectomy was clinically insignificant with optical biometry (-0.10 D, -0.22 to 0.02;, 8 studies, 453 eyes), and) and a mild myopic shift was possible with ultrasound biometry (-0.39 D, 95% CI: -0.68 to -0.09 D; 6 studies, 529 eyes). The 95% CR was greater and more variable with ultrasound biometry in patients who underwent phacovitrectomy (median 1.75 D, range 0.47-2.5) while it was consistent and lower with optical biometry in patients who underwent phacoemulsification (median 0.96 D, range 0.60-1.2]).

CONCLUSIONS

Phacovitrectomy causes a mild myopic shift compared to phacoemulsification, which is clinically relevant only with ultrasound biometry. Furthermore, our review provides estimates of fixed and random error for postoperative vs. target spherical equivalent as a continuous variable, that is easy to use as benchmark for quality assurance.

Two-Year Reproducibility of Axial Length Measurements after Combined Phacovitrectomy for Epiretinal Membrane, and Refractive Outcomes

Purpose: To determine the long-term reproducibility of axial length measurements and mean postoperative prediction errors after combined phacovitrectomy in patients with idiopathic epiretinal membranes. Design: Retrospective cohort study. Methods: The study included 43 patients who underwent combined phacovitrectomy and 30 patients who underwent only phacoemulsification. To determine the effect of vitrectomy, we compared patients treated with phacoemulsification only versus those treated with combined phacovitrectomy. Axial lengths were measured three times with a one-year interval, and the intraclass correlation coefficient (ICC), coefficient of variation (CV), and test–retest standard deviation (TRTSD) were assessed. Results: There was no significant change in axial length, and axial length measurements showed high reproducibility in all groups. ICC, CV, and TRTSD values were 0.997, 0.24%, and 0.056, respectively, for the vitrectomized eyes. The mean postoperative prediction error was −0.37 diopters(D) in vitrectomized eyes (p < 0.001), while it was +0.11 D in patients with phacoemulsification (p = 0.531). The myopic shift was more obvious in eyes with a shallower anterior chamber (p = 0.008) and a thicker lens (p = 0.025). Conclusions: Axial length measurements showed excellent long-term reproducibility at 2 years after combined phacovitrectomy. Myopic shifts were observed after combined phacovitrectomy, which was probably due to changes in the effective lens position after combined phacovitrectomy, rather than to changes in the axial length.

Combined phaco-vitrectomy provides lower costs and greater area under the curve vision gains than sequential vitrectomy and phacoemulsification

PURPOSE

A majority of phakic patients undergoing pars plana vitrectomy for epiretinal membrane or macular hole require subsequent cataract surgery within 1-2 years. Combined phaco-vitrectomy eliminates the need for a second surgery and may enable patients to attain their best vision sooner. This study aims to compare the visual outcomes, complication rates, and costs of combined phaco-vitrectomy versus sequential vitrectomy followed by cataract surgery.

METHODS

Records were searched by CPT® codes to identify patients with both cataract and vitrectomy surgery at our institution over a 5-year period (2013-2018). Chart review included medical history, demographics, exam findings, operating room records, visual acuity (VA), and clinical outcomes. Statistical analyses were performed with SPSS v19 (IBM). Area under the curve for visual acuity was calculated as the trapezoidal mean of the change in Early Treatment of Diabetic Retinopathy Study letters.

RESULTS

After exclusion, 81 eyes of 78 patients underwent both cataract and vitrectomy surgeries at our institution. Thirty-four eyes underwent separate, sequential vitrectomy then phacoemulsification surgery, and 47 eyes had combined phaco-vitrectomy surgery. Total operating room times (120.81 ± 3.41 vs 161.03 ± 5.45 min; p < 0.0001) and associated costs were significantly lower in the combined surgery compared with those in the sequential surgery group. Baseline and final visual acuity were similar between the two groups. Baseline VA was 35.53 letters (~ 20/200) and 32.81 letters (~ 20/220) and increased to final VA of 63.74 (~ 20/53) and 60.91 letters (~ 20/61), in the sequential and combined groups respectively. Area under the curve for vision was greater in the combined surgery group, with subjects gaining an average of + 9.11 ± 3.32 letters from sequential surgery, and + 19.53 ± 3.53 letters in the combined surgery group (p = 0.04). Additionally, patients in the combined group attained their best visual acuity 449 days (15 months) sooner than those receiving sequential surgery.

CONCLUSIONS

Combined phaco-vitrectomy surgery resulted in greater area under the curve visual acuity benefit and attainment of best visual acuity 15 months sooner compared with conventional sequential surgeries. There were no significant differences in complication rates or clinical outcomes between the groups, but operative times and costs were lower for combined surgery, supporting a favorable cost-benefit ratio. Graphical abstract.

Vitreoretinal Surgery in the Post-Lockdown Era: Making the Case for Combined Phacovitrectomy

The coronavirus disease (COVID-19) pandemic has significantly limited the capacity of healthcare systems to provide elective services like cataract surgery. Cataract formation is a frequent complication after pars plana vitrectomy. In this paper, we review the pros and cons of combined phacovitrectomy as opposed to sequential surgery in the post-pandemic era. In particular, we discuss the patient-level visual benefits and societal economic advantages of this procedure.

Prospective Comparison of Intraocular Lens Dynamics and Refractive Error between Phacovitrectomy and Phacoemulsification Alone

PURPOSE

To compare intraocular lens (IOL) dynamics and refractive prediction errors between eyes that underwent phacovitrectomy and eyes that underwent phacoemulsification alone.

DESIGN

Prospective, nonrandomized, comparative, observational study.

PARTICIPANTS

Sixty eyes of 60 patients who underwent 25-gauge phacovitrectomy without gas injection for macular pathology and 60 eyes of 60 patients who underwent phacoemulsification alone for cataract were enrolled.

METHODS

Preoperative optical biometry was performed using the IOLMaster 700 (Carl Zeiss Meditec, Inc, Dublin, CA) to calculate the IOL power with the Barrett Universal II formula. Monofocal, nontoric, single-piece foldable aspherical IOLs were implanted in each patient. Comprehensive ocular examinations, including CASIA2 (Tomey Corp, Nagoya, Japan) evaluations of the preoperative crystalline lens and postoperative IOL positions (i.e., decentration, tilt, and aqueous depth), were performed before and 3 days, 1 month, and 3 months after surgery.

MAIN OUTCOME MEASURES

Refractive prediction errors and IOL dynamics.

RESULTS

Mean refractive prediction errors at 3 days, 1 month, and 3 months after phacovitrectomy were 0.51±0.59 diopters (D), 0.11±0.40 D, and 0.05±0.41 D, respectively, whereas those after phacoemulsification alone were 0.43±0.38 D, 0.11±0.37 D, and 0.07±0.34 D, respectively. There was no significant difference in the refractive error between the 2 groups at any time point. A myopic shift of -0.50 D or more negative refractive error occurred in 4 (6.7%) of 60 eyes with phacovitrectomy and 3 (5.0%) of 60 eyes with phacoemulsification alone; there was no significant between-group difference. At 3 months postoperatively, refractive errors within ±0.50 D and ±1.00 D were achieved in 49 (81.7%) and 58 (96.7%) of 60 eyes in the phacovitrectomy group and 52 (86.7%) and 60 (100.0%) of 60 eyes in the phacoemulsification alone group, again without any significant between-group differences. There were no significant differences in the preoperative lens and postoperative IOL positions between the 2 study groups, except for a significantly deeper mean aqueous depth at 3 days after surgery in the phacovitrectomy group.

CONCLUSIONS

Neither myopic shift nor IOL displacement occurs after 25-gauge phacovitrectomy with a single-piece IOL without gas injection for macular pathology compared with phacoemulsification alone.

Comparison of postoperative refractive outcome in eyes undergoing combined phacovitrectomy vs cataract surgery following vitrectomy

BACKGROUND

To investigate the accuracy of preoperative biometry in eyes undergoing combined phacovitrectomy and to compare it with eyes having cataract surgery at a later point in time following vitrectomy.

METHODS

Patients with epiretinal membrane or macular hole who underwent combined phacovitrectomy (group 1) or phacoemulsification following pars plana vitrectomy (PPV) (group 2) were included in this retrospective, comparative, interventional case series. The primary outcome measures were the intraocular lens power prediction error (PE) and the percentage of eyes with PE > ± 0.5D in the two groups. Secondary outcome measures included the correlation between epidemiological, clinical, or surgical factors and dioptric shift. In addition, the influence of optical coherence tomography characteristics to the PE was investigated.

RESULTS

Group 1 and 2 consisted of 55 and 54 eyes, respectively, for a total of 109 eyes included in the study. The mean absolute PE was 0.59 D (range + 1.4 to - 2.5D) in group 1 and 0.35 (range + 1.0 to - 1.45D) in group 2 (p = 0.01). PE greater than 0.5D was observed in 47% of eyes in group 1 as opposed to 16.6% of eyes in group 2 (p = 0.027). The PE was associated with shallower anterior chamber depth (ACD), increased central macular thickness (> 300 μ), and worse baseline best-corrected visual acuity. Photoreceptor ellipsoid zone or external limiting membrane disruption was not associated with significantly greater postoperative refractive deviations.

CONCLUSION

Combined phacovitrectomy may result in greater postoperative refractive prediction error compared to phacoemulsification alone following vitrectomy. Patients with worse vision, greater central macular thickness, and shallow anterior chambers require more caution since they are prone to inaccurate preoperative biometry.

Secondary intraocular lens implantation: Complication rates, visual acuity, and refractive outcomes

PURPOSE

To compare complication rates, visual acuity, and refractive outcomes of secondary intraocular lens (IOLs) implantation.

SETTING

Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA.

DESIGN

Retrospective case series.

METHODS

All secondary IOLs placed by the anterior segment service were reviewed. Preoperative data, operative reports, and data from each subsequent postoperative visit were evaluated. Patients were divided into 5 groups based on the final IOL position: (1) sulcus with optic capture, (2) sulcus without optic capture, (3) anterior chamber (AC), (4) iris-fixated, and (5) transscleral-sutured. Complication rates, visual acuity, and refractive outcomes were compared for each group.

RESULTS

The sulcus with and without optic capture groups had the lowest complication rates and best visual acuity outcomes. There was no difference in final corrected distance visual acuity (CDVA) between the transscleral-sutured IOL, iris-fixated IOL, and AC IOL groups, although the AC IOL group had the lowest rates of early postoperative complications and a significant improvement in vision. The transscleral-sutured IOL group had the highest complication rates, and 25% of patients in the iris-fixated IOL group lost 2 or more lines of CDVA.

CONCLUSIONS

When a secondary IOL cannot be placed within the capsular bag, sulcus with optic capture is the best alternative, followed by sulcus without optic capture. There was no difference in visual acuity outcomes between transscleral-sutured IOLs, iris-fixated IOLs, and AC IOLs. Anterior chamber IOLs resulted in fewer early complications.

Effect of Nd:YAG Laser Capsulotomy on Anterior Segment Parameters in Patients with Posterior Capsular Opacification after Phacovitrectomy

Purpose

To compare changes in anterior segment parameters after Nd:YAG laser capsulotomy in eyes that underwent either combined phacovitrectomy or cataract surgery.

Methods

This retrospective study enrolled 37 eyes of 35 patients with posterior capsular opacification treated with combined phacovitrectomy (group A), and 35 eyes of 32 patients with posterior capsular opacification treated with cataract surgery (group B). Anterior segment parameters, including anterior chamber depth (ACD), anterior chamber angle, and anterior chamber volume, were measured by a Pentacam before Nd:YAG laser capsulotomy and 1 hour, 1 day, 1 week, 1 month, and 3 months after this treatment.

Results

In the cataract surgery group, the ACD was significantly lower 1 day (3.75 ± 0.74 mm), 1 week (3.73 ± 0.24 mm), and 3 months (3.74 ± 0.33 mm) after Nd:YAG laser capsulotomy compared with the pretreatment value (4.20 ± 0.62 mm, p = 0.002). By contrast, the ACD did not change significantly over time in the combined phacovitrectomy group. The ACD differed significantly between the two groups at 1 week, 1 month, and 3 months after capsulotomy. There were no significant changes in the anterior chamber volume, anterior chamber angle, central corneal thickness, or pupil size from before to after capsulotomy in either group. A non-significant trend toward myopic shift was observed in group A (p = 0.072) and B (p = 0.055).

Conclusions

The results of the present study may help determine the power of the intraocular lens in patients who underwent combined surgery or cataract surgery and who will receive Nd:YAG laser capsulotomy.

Optical Biometry-Based Intraocular Lens Calculation and Refractive Outcomes after Phacovitrectomy for Rhegmatogenous Retinal Detachment and Epiretinal Membrane

We investigate the refractive error after phacovitrectomy for rhegmatogenous retinal detachment (RRD; 100 eyes) and epiretinal membrane (ERM; 102 eyes). Axial lengths were measured by optical biometry in most patients. The main outcome measures were the refractive and absolute prediction errors. The overall mean refractive prediction error (ME) and mean absolute prediction error (MAE) were −0.40 ± 0.72 D and 0.62 ± 0.55 D, respectively, at 3 months postoperatively. The ME and MAE were significantly higher in the RRD group than in the ERM group (−0.63 ± 0.74 D vs −0.16 ± 0.63 D, P < 0.001 and 0.75 ± 0.62 D vs 0.49 ± 0.43 D, P = 0.002, respectively), indicating greater myopic shift in the RRD group. In the RRD group, adding +0.5 D to the preoperative predicted refractive power decreased the postoperative ME and MAE to −0.13 ± 0.74 D and 0.58 ± 0.47 D, respectively. Based on our results, we conclude that postoperative myopic shift was significantly higher in the RRD group than in the ERM group, possibly because of forward displacement of the intraocular lens by gas tamponade. The myopic shift can be minimized by adding +0.5 D to the predicted refractive power in patients undergoing phacovitrectomy for RRD.

Epiretinal membrane surgery: an analysis of 2-step sequential- or combined phacovitrectomy surgery on refraction and macular anatomy in a prospective trial

PURPOSE

To assess the impact of combined phacoemulsification-vitrectomy and sequential surgery for idiopathic epiretinal membrane (ERM) on refractive error (RE) and macular morphology.

METHODS

In this prospective clinical trial, we allocated phakic eyes with ERM to (1) cataract surgery and subsequent pars plana vitrectomy (PPV) (CAT group), (2) PPV and subsequent cataract surgery (VIT group) or (3) phaco-vitrectomy (COMBI group). Examinations were at baseline, one month after each surgery, and at 3 months and 12 months of follow-up. Primary outcome was the RE (the difference between predicted and achieved spherical equivalent); secondary outcomes were best-corrected visual acuity (BCVA), and incidence of cystoid macular oedema (CME) defined as >10% increment of central subfield macular thickness (CSMT).

RESULTS

Sixty-two eyes were enrolled. The mean RE showed a small myopic shift of -0.36D in all groups 1 month after surgery, decreasing after 12 months to -0.17D. The absolute value of the RE (ARE) ranged 0.49-0.68D after 12 months. In the immediate postoperative period, there was a higher incidence of CME in the CAT group. There was no significant difference in final RE, ARE, BCVA and CSMT between the groups. Four cases (17%) in the CAT group had resolved visual complaints and improved BCVA after cataract surgery resulting in no need for PPV within the follow-up period.

CONCLUSION

Surgery for idiopathic ERM in phakic eyes with either phaco-vitrectomy or sequential surgery are equal approaches with respect to functional- (RE, BCVA) and anatomical outcomes (CME, CSMT). However, if starting with cataract surgery, 17% of the cases may not need subsequent PPV.

Myopic shift in a pseudophakic eye with an accommodating IOL following vitrectomy with gas tamponade

Purpose

To report the case of a patient with Crystalens, an accommodating posterior-chamber intraocular lens (IOL), who experienced a myopic shift following subsequent vitrectomy with gas tamponade. We propose a hypothesis as to why this myopic shift occurred and analyze its validity based on current literature.

Observations

A patient had cataract surgery with implantation of a Crystalens AT-50AO +21D. Preoperative A-scan measured anterior chamber depth (ACD) to be 3.69 mm. The refraction was emmetropic following cataract surgery. Nine months later, the patient required pars plana vitrectomy with gas tamponade for a rhegmatogenous retinal detachment, followed by vitrectomy, membrane peel, and air/fluid exchange for epiretinal membrane. The retinal repair was anatomically successful, however, the patient experienced a −1.0 D myopic shift. ACD measurement following vitrectomy was 5.08 mm.

Conclusions and importance

Myopic shift following vitrectomy with gas tamponade in pseudophakic eyes is widely reported. This patient's myopic shift was assumed due to anterior movement of the Crystalens caused by a gas bubble placed during retinal detachment repair as this is the prevailing theory in the literature [1]. However, a comparison of the patient's ACD measurements does not support the above hypothesis. Further study is needed to determine the mechanism of myopic shift seen in pseudophakic patients following vitrectomy, specifically those with gas.

Post-operative Refractive Prediction Error After Phacovitrectomy: A Retrospective Study

Introduction

Many authors have reported on a myopic post-operative refractive prediction error when combining phacoemulsification with pars plana vitrectomy (phacovitrectomy). In this study we evaluate the amount of this error in our facility and try to elucidate the various factors involved.

Methods

This was a retrospective study which included 140 patients who underwent phacovitrectomy (39 with macular holes, 88 with puckers, and 13 with floaters). Post-operative refractive error was defined as the difference between the actual spherical equivalent (SEQ) and expected SEQ based on the SRK/T and Holladay-II formulas. Both univariate (paired t test, independent t test, one-way analysis of variance, or Mann–Whitney test) and multivariate (regression analysis) statistical analyses were performed.

Results

Overall, a refractive error of − 0.13 dpt (p = 0.033) and − 0.26 dpt (p < 0.01) were found in the SRK/T and Holladay-II formulas, respectively. For the independent diagnoses, only macular holes showed a myopic error with the SRK/T (− 0.31 dpt; p < 0.01) and Holladay-II (− 0.44 dpt; p < 0.01) formulas. In univariate analysis, significant factors involved in myopic refractive error were macular hole as diagnosis (p < 0.01 for SRK/T and Holladay-II), gas tamponade (SRK/T p = 0.024; Holladay-II p = 0.025), pre-operative myopia (p < 0.01 for SRK/T), and optical technique for axial length measurement (SRK/T and Holladay-II p < 0.01). In the multivariate analysis, pre-operative axial length (p = 0.026), optical technique for axial length measurement (p < 0.01), and pre-operative SEQ (p < 0.01) were independent predictors for myopic refractive error in the SRK/T formula. For the Holladay-II formula, optical technique for axial length measurement (p < 0.01) and pre-operative SEQ (p = 0.04) were predictive.

Conclusion

Various factors are involved in determining the myopic refractive error after phacovitrectomy. Not every factor seems to be as important in each individual patient, suggesting a more tailored approach is warranted to overcome this problem.

Changes in Anterior Chamber Depth after Combined Phacovitrectomy

Objectives:

To evaluate changes in anterior chamber depth (ACD) and postoperative refractive outcomes after combined phacovitrectomy.

Materials and Methods:

This study included 10 eyes of 10 patients that underwent combined phacovitrectomy (study group) and 14 eyes of 14 patients that underwent phacoemulsification surgery (control group) at İstanbul Medipol University Ophthalmology Department. Preoperative and 3-month postoperative best corrected visual acuity (BCVA), ACD, change in ACD and refractive outcomes were compared between the two groups.

Results:

Preoperative ACD, postoperative ACD at 3 months and change in ACD were similar between two groups (p=0.403, p=0.886, p=0.841). Postoperative mean refractive outcomes were 0.22±0.51 diopter in the phacovitrectomy group and -0.39±0.53 diopter in the phacoemulsification group (p=0.019). BCVA was increased in both groups (p=0.001).

Conclusion:

Postoperative refractive outcomes in eyes that underwent combined phacovitrectomy are different from those in eyes that underwent only phacoemulsification surgery. This is important in determining preoperative intraocular lens power before combined phacovitrectomy.

Comparison of 1.8-mm incision versus 2.75-mm incision cataract surgery in combined phacoemulsification and 23-gauge vitrectomy

PURPOSE

To compare 1.8 mm micro-incision and 2.75 mm standard incision in coaxial cataract surgery combined with 23-Gauge (23G) vitrectomy with respect to intraoperative and postoperative complications and outcomes.

METHODS

In this prospective study 30 eyes of 30 patients planned for combined phacoemulsification and 23G vitrectomy were enrolled, and randomized to undergo either Standard 2.75 mm Incision Cataract Surgery (SICS, 15 eyes) or Coaxial 1.8 mm Micro-Incision Cataract Surgery (C-MICS, 15 eyes) followed by vitrectomy. Inclusion criteria were cataract and macular disorders including macular hole, epiretinal membrane and vitreomacular traction. Data were collected at preoperative evaluation and 1 and 12 months or more after surgery.

RESULTS

Incision leakage occurred in two eyes (7%: one per group), retinal break in nine (30%: four in C-MICS, five in SICS). Fibrin in anterior chamber (AC) occurred day 1 in three eyes (10%: two C- and one SICS). Posterior capsule opacification developed in 22 eyes (78%: 13 MICS, nine SICS, p = 0.1). A myopic shift of -0.63 ± 0.7 was noted (-0.59 ± 0.8 MICS, -0.68 ± 0.6 SICS, p = 0.74). Surgically induced astigmatism (SIA) was significantly smaller in C-MICS group (ΔKP, -0.019 ± 0.095 versus -0.141 ± 0.219, p = 0.0038) at 1 month but not at final follow-up (ΔKP, 0.0005 ± 0.16 in C-MICS versus -0.057 ± 0.12, p = 0.3 CONCLUSIONS: Both techniques were equally safe with respect to intraoperative and postoperative findings. Coaxial micro-incision cataract surgery (C-MICS) was associated with less surgically-induced astigmatism (SIA) 1 month after surgery but differences were not statistically significant at final follow-up indicating a faster refractive recovery with C-MICS than with SICS.

Intraocular lens power estimation in combined phacoemulsification and pars plana vitrectomy in eyes with epiretinal membranes: a case-control study

PURPOSE

To evaluate the accuracy of postoperative refractive outcomes of combined phacovitrectomy for epiretinal membrane (ERM) in comparison to cataract surgery alone.

MATERIALS AND METHODS

Thirty-nine eyes that underwent combined phacovitrectomy with intraocular lens (IOL) implantation for cataract and ERM (combined surgery group) and 39 eyes that received phacoemulsification for cataract (control group) were analyzed, retrospectively. The predicted preoperative refractive aim was compared with the results of postoperative refraction.

RESULTS

In the combined surgery group, refractive prediction error by A-scan and IOLMaster were -0.305±0.717 diopters (D) and -0.356±0.639 D, respectively, compared to 0.215±0.541 and 0.077±0.529 in the control group, showing significantly more myopic change compared to the control group (p=0.001 and p=0.002, respectively). Within each group, there was no statistically significant difference in refractive prediction error between A-scan and IOLMaster (all p>0.05). IOL power calculation using adjusted A-scan measurement of axial length based on the macular thickness of the normal contralateral eye still resulted in significant postoperative refractive error (all p<0.05). Postoperative refraction calculated with adjusted axial length based on actual postoperative central foveal thickness change showed the closest value to the actual postoperative achieved refraction (p=0.599).

CONCLUSION

Combined phacovitrectomy for ERM resulted in significantly more myopic shift of postoperative refraction, compared to the cataract surgery alone, for both A-scan and IOLMaster. To improve the accuracy of IOL power estimation in eyes with cataract and ERM, sequential surgery for ERM and cataract may need to be considered.

Postoperative refractive error after phacovitrectomy for epiretinal membrane with and without macular oedema

PURPOSE

This study was initiated to investigate whether the presence of macular oedema influenced intraocular lens (IOL) power calculation in eyes with epiretinal membrane.

METHODS

The files of patients undergoing combined phacoemulsification were retrospectively reviewed. Two groups were defined according to presence of macular oedema. The main outcome measure was the IOL power prediction error (PE). Secondary outcome measures were the correlation between preoperative macular thickness, absolute change of macular thickness and dioptric shift. The mean postoperative PE achieved with the Haigis formula was compared with the PE that would have been obtained had the SRKII and HofferQ formulas been used.

RESULTS

We investigated 47 eyes of 47 consecutive patients. Regardless of the IOL formula used, the PE was on average higher in eyes without macula oedema (group 1). The myopic dioptric shift was dependent on preoperative macular thickness and absolute change of macular thickness. This association was more markedly pronounced in group 1.

CONCLUSIONS

Increased retinal thickness is the main cause for underestimation of the cornea-photoreceptor layer distance, and therefore could contribute to inaccuracy in IOL power calculations. The current results show that a myopic shift tends to be less pronounced in cases where a macula oedema is present. Eyes with pure traction have less predictable refractive results in terms of higher PE and dioptric shift.