A Preservative-Free Approach - Effects on Dry Eye Signs and Symptoms After Cataract Surgery.

Purpose: To compare the effect of treatment with preservative-free dexamethasone, NSAIDs and trehalose/hyaluronic acid eye drops with the preservative benzalkonium chloride containing dexamethasone and NSAIDs after cataract surgery in dry versus non-dry eyes. Patients and Methods: In this prospective randomized intervention study, dry eye tests were performed before and 6 weeks after cataract surgery. Patients were considered as having dry eye, SDE (sign of dry eye), if at least one of the following dry eye tests were abnormal; corneal fluorescein staining (CFS), non-invasive keratograph breakup time (NIKBUT) or tear osmolarity. Patients with SDE were randomly assigned to one of two groups. Group 1 patients were treated with dexamethasone and bromfenac eye drops with the preservative benzalkonium chloride (BAC). Group 2 patients were treated with preservative-free dexamethasone and preservative-free diclofenac, as well as a preservative-free lubricant with trehalose and hyaluronic acid both before and after surgery. Patients with normal tear film status acted as the control group (group 3) and received same treatment as group 1. Results: A total of 215 patients were enrolled six weeks after surgery, the number of patients with SDE decreased significantly in groups 1 and 2 (p <0.001). Subjective symptoms and objective measures including osmolarity, NIKBUT, CFS, and tear film thickness (TFT) improved after surgery, tear production remained unchanged, while corneal sensitivity and meibomian gland dysfunction (MGD) parameters worsened. In the control group with normal tear-film status, SDE increased significantly after the surgery (p <0.001). There were no statistically significant differences in tear film parameters between the three groups after surgery. Conclusion: After cataract surgery, patients with mild to moderate dry eyes may experience improved tear film status and reduced symptoms. However, we found no additional beneficial effect on dry eye parameters with treatment with preservative-free dexamethasone, NSAIDs, and lubricants compared to preservative-containing eye drops.

Prevalence of Dry Eye Disease Among Individuals Scheduled for Cataract Surgery in a Norwegian Cataract Clinic.

Purpose: To determine the prevalence of dry eye disease (DED) in patients scheduled for cataract surgery in a Norwegian eye clinic. Patients and Methods: 218 patients scheduled for cataract surgery were examined for DED in one randomly selected eye and questioned regarding symptoms and risk factors. Patients were diagnosed with DED if they fulfilled the DEWS II criteria with symptom score >12/100 with Ocular Surface Disease Index (OSDI) questionnaire, and the presence of any of the three signs: tear osmolarity >307 mOsm/L in either eye or a difference in osmolarity between the two eyes of >8 mOsm/L, corneal fluorescein staining (CSF) ≥ grade 2 and non-invasive tear film breakup time (NIKBUT) of <10 seconds. Additional tests were the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, tear meniscus height (TMH), Schirmer 1, tear film thickness (TFT), corneal sensitivity and meibography (meiboscore). Dry eye test outcomes were correlated with risk factors for DED. Results: The prevalence of DED was 55.5% according to the DEWS II criteria. The abnormal osmolarity percentage was 66.5, while 29.8% had shortened NIKBUT and 19.7% exhibited CFS ≥2. 57% had Schirmer 1 ≤ 10 mm/5 min, and 81.1% had a meiboscore of ≥1. 71.2% of subjects scored positive for DED symptoms using the OSDI questionnaire and 69.3% using SPEED. Logistic regression analysis showed that higher age correlated with a lower OSDI symptom score, reduced corneal sensitivity and increased meibomian gland atrophy. Female sex was associated with higher odds of having DED, abnormal NIKBUT and abnormal CFS. Ocular tests for DED did not correlate with OSDI symptom scores when assessed with Spearman`s rank analysis. Conclusion: The prevalence of DED in an elderly Norwegian population scheduled for cataract surgery is high and associated with female sex. There was a lack of correlation between signs and symptoms of DED.

The Significance of Inter-Eye Osmolarity Difference in Dry Eye Diagnostics.

Purpose: The purpose of this study was to evaluate the diagnostic value of inter-eye osmolarity differences in relation to dry eye symptoms and other non-osmolar signs of dry eye disease. Patients and Methods: One hundred ninety one participants who attended a larger interventional study of dry eye disease prior to and after cataract surgery were analyzed for dry eye disease (DED). Dry eye diagnostics were performed for all subjects according to the DEWS II criteria: tear osmolarity was collected from both eyes with the TearLab system, non-invasive Tear film break up time (NIKBUT) was obtained on the test eye with Keratograph and ocular surface staining (OSS) was evaluated using the Oxford schema. The Ocular Surface Disease Index (OSDI) questionnaire was used to assess symptoms. Inter-eye osmolarity greater than 8, which is considered as a sign of DED according to the TearLab user manual, was evaluated and compared with other non-osmolar signs of DED. Results: The 191 subjects were divided into three groups according to osmolarity measurements. Sixty-five subjects had normal osmolarity (below 308 mOsmol/L in both eyes and less than 9 mOsmol/L difference between the eyes), 107 had high osmolarity (308 mOsmol/L or higher in one of the eyes) and 19 had an inter-eye difference >8 mOsmol/L or higher, with neither eye having osmolarity higher than 307 mOsmol/L. Signs and symptoms in this last group were not correlated with the high osmolarity group or the normal group, though they appeared more similar to the normal group. Conclusion: The diagnostic value of inter-eye osmolarity difference in predicting symptoms or other non-osmolar signs of dry eyes appears weak. Our study suggests that the criterion of an inter-eye difference of 8 mOsmol/L is not a useful cut-off for diagnosing dry eyes based on osmolarity.

Refractive and Visual Outcomes After Implantation of a Secondary Toric Sulcus Intraocular Lenses.

PURPOSE: To evaluate the rotational stability, visual acuity and refractive error after sulcus implantation of a secondary toric IOL. SETTING: One clinical practice in Haugesund, Norway. DESIGN: Non-interventional single-arm diagnostic study. METHODS: Eligible subjects who had previous successful primary cataract or refractive lens exchange surgery in one or both eyes and the AddOn® secondary toric IOL implanted in the sulcus were evaluated at a single postoperative diagnostic visit to measure visual outcomes. Subjects with surgical complications (either primary or secondary) or pathology that would affect best-corrected visual acuity (eg, amblyopia) were excluded. Clinical evaluations at the diagnostic visit included measurement of visual acuity, manifest refraction and IOL orientation. RESULTS: Eighteen eyes were evaluated. After secondary IOL implantation, mean residual refractive astigmatism was significantly reduced (1.66 ± 0.92 to 0.32 ± 0.25 D). There was no appreciable change in the spherical equivalent refraction. Sixteen of 18 eyes (89%) had residual refractive astigmatism ≤0.50D, and no eye had more than 0.75D after secondary IOL implantation. Mean UCVA was 0.00 ± 0.03 logMAR, with no eyes worse than 0.10. Mean BCVA was -0.05 ± 0.03 logMAR (20/20+2), with all eyes having BCVA of 0.00 logMAR. The mean change in orientation was near zero, with a mean absolute change of 4.9 ± 3.7 degrees. Sixteen of 18 eyes (89%) had a lens orientation ≤10 degrees from intended, with no eye oriented more than 13 degrees from intended. CONCLUSION: The AddOn® toric sulcus IOL significantly reduced postoperative refractive astigmatism in patients with high astigmatism after their primary cataract or RLE surgery, providing very good uncorrected distance vision.

Comparing Visual Acuity, Low Contrast Acuity and Contrast Sensitivity After Trifocal Toric and Extended Depth of Focus Toric Intraocular Lens Implantation.

PURPOSE: The aim of this study was ï»¿to compare visual acuity at various distances (far, intermediate and near), low contrast acuity and contrast sensitivity after trifocal toric and extended depth of focus (EDOF) toric intraocular lens (IOL) implantation. PATIENTS AND METHODS: This was a non-interventional two-arm comparative study of visual outcomes after uncomplicated bilateral cataract or refractive lens exchange surgery with IOL implantation between 6 months and 5 years before a single diagnostic examination visit. There was no masking and no control group. Subjects had to have uncorrected distance visual acuity (UDVA) of 20/40 (0.3 logMAR) or better measured at the time of their study visit. Clinical evaluations included the manifest refraction, visual acuity (VA) at distance, intermediate (60 cm) and near (40 cm), low contrast (10%) VA and contrast sensitivity. RESULTS: A total of 50 bilaterally implanted patients (25 trifocal, 25 EDOF) were examined; the two groups had similar characteristics, including corneal astigmatism. Postoperative refractive outcomes were also similar. There were no statistically significant differences in distance or intermediate VA between groups, but the trifocal group had significantly better near VA both uncorrected (p = 0.009) and distance-corrected (p = 0.014). There were no statistically significant differences in the low contrast acuity measures between IOLs at either distance or 40 cm, with or without glare. Contrast sensitivity in mesopic and photopic conditions was similar. CONCLUSION: The trifocal and EDOF toric IOLs performed similarly for all measures except near VA, where the trifocal toric provided significantly better acuity. For subjects interested in reducing spectacle independence at near, this may be an important consideration.

Prevalence of Signs and Symptoms of Dry Eye Disease 5 to 15 After Refractive Surgery.

PURPOSE: To compare the prevalence of dry eye disease (DED) as determined by signs and symptoms in patients with a history of laser vision correction (LVC) or implantable collamer lens (ICL) implantation 5-15 years ago with a matched control group with no history of refractive surgery. PATIENT AND METHODS: This was a cross-sectional case-control study. The subject population included patients who had LVC or ICL 5 to 15 years ago. The control group was age matched. A test eye was randomly chosen. Subjects were required to have good ocular health. DED was evaluated using categorical cut-off criteria for tear film osmolarity (measured in both eyes), the subjective Ocular Surface Disease Index (OSDI), the dynamic Objective Scatter Index (OSI), non-invasive keratography tear break-up time (NIKBUT), meibography, and the Schirmer 1 test. RESULTS: The study included 257 subjects (94 LVC, 80 ICL, 83 control). The frequency of hyperosmolarity was significantly higher in the LVC group vs the control (73% vs 50%, p = 0.002), In contrast, the frequency of subjective symptoms tended to be lower in the LVC group than in the control group (19% vs 31%; p = 0.06). These differences were not seen between the ICL and control group. CONCLUSION: The results suggest that LVC may cause tear film instability as indicated by hyperosmolar tears up to 15 years after surgery, with few subjective symptoms of dry eye. This may have implications for IOL calculations for cataract or refractive lens exchange later in life.

Combined low level light therapy and intense pulsed light therapy for the treatment of meibomian gland dysfunction.

PURPOSE: To evaluate the effects of combined intense pulsed light therapy (IPL) and low-level light therapy (LLLT) on clinical measures of dry eye related to severe meibomian gland disease (MGD) in subjects unresponsive to previous medical management. PATIENTS AND METHODS: This was a retrospective chart review of patients treated by 4 physicians at 3 centers. All patients were documented treatment failures with traditional pharmaceutical therapy. They all had their MGD evaluated before treatment using a grading scale (0-4), tear breakup time in seconds and the Ocular Surface Disease Index (OSDI) questionnaire. To be included, all patients had to have had a short course of adjunct pharmaceutical or device-related therapy, along with a combined IPL/LLLT treatment. As well, a second MGD evaluation with the same three measures had to have been conducted 1-3 months post treatment. RESULTS: A total of 460 eyes of 230 patients were identified for inclusion in the data set. Mean OSDI scores were significantly lower after treatment; 70.4% of patients had pretreatment OSDI scores indicative of dry eye; this dropped to 29.1% of patients after treatment. A 1-step or greater reduction in MGD grading was observed in 70% of eyes, with 28% of eyes having a 2-step or greater reduction. Tear breakup time was ≤6 seconds in 86.7% of eyes pretreatment, dropping to 33.9% of eyes after treatment. There were no ocular or facial adverse events or side effects related to the combined light treatment. CONCLUSION: The use of combined IPL/LLLT for the treatment of severe MGD appears to be beneficial in patients who have failed topical and/or systemic therapy.

Clinical outcomes with distance-dominant multifocal and monofocal intraocular lenses in post-LASIK cataract surgery planned using an intraoperative aberrometer.

IMPORTANCE: Studies evaluating the clinical benefits of intraoperative aberrometry (IA) in cataract surgery are limited. BACKGROUND: The study was designed to determine whether IA improved clinical outcomes of post-laser in situ keratomileusis (LASIK) cataract surgery with different intraocular lenses (IOLs) implanted. DESIGN: A retrospective chart review of clinical outcomes from one surgeon at one surgical centre was conducted. It included post-LASIK cataract surgeries where IA was used for the confirmation of IOL power, with either a distant-dominant multifocal IOL or a monofocal IOL implanted. PARTICIPANTS: Records for 44 eyes of 31 patients were analysed. METHODS: Differences in visual acuity (VA) and refractions by lens type were compared, and the effects of IA were evaluated. MAIN OUTCOME MEASURES: Uncorrected distance VA and the percentage of eyes with a spherical equivalent refraction within 0.5D of the intended correction were the primary outcome measures. RESULTS: There was no statistically significant difference in the percentage of eyes with uncorrected distance VA of 20/25 or better between IOL groups (P = 0.41). More eyes in the multifocal group had a refraction within 0.50D of intended (P = 0.03). In 39% of cases, the preoperative and IA power calculations suggested the same IOL power. When not equal, the IA results were not significantly more likely to be 'best' (P = 0.08). CONCLUSIONS AND RELEVANCE: Results suggest that a history of previous LASIK is not a contraindication to use of distant-dominant multifocal IOLs. IA did not appear to improve clinical outcomes in post-LASIK eyes, although a positive trend was evident.

A review of results after implantation of a secondary intraocular lens to correct residual refractive error after cataract surgery.

PURPOSE: The purpose of this study was to provide clinical outcomes data related to secondary intraocular lens (IOL) implantation for the correction of residual refractive error after cataract surgery. PATIENTS AND METHODS: A chart review was conducted to identify all eyes implanted with the monofocal spherical or toric AddOn® secondary IOL. Data were collated from charts where uncomplicated initial cataract surgery was completed. Measures of interest included the original IOL implanted, the postoperative refractive error (before secondary IOL implantation) and the associated corrected and uncorrected visual acuities (VAs). Postoperative data of interest included the residual refractive error, the best-corrected visual acuity (BCVA) and uncorrected visual acuity (UCVA). RESULTS: Refractive and VA data from 1 week to 3 months post-surgery were available for 46 of 70 eyes implanted with a secondary IOL by one surgeon at one practice between 4/15 and 3/17. There was a statistically significant improvement in UCVA of about 2 lines after surgery (p<0.01), with no change in BCVA (p=0.94). No eyes lost a line of BCVA. There was a statistically significant reduction in the absolute magnitude of the residual spherical equivalent refractive error (p<0.01). In the 10 cases with a toric secondary IOL, there was a statistically significant reduction in refractive cylinder (p<0.01). CONCLUSION: The secondary IOL studied here appears to be a viable surgical option to correct residual refractive error after primary IOL implantation.

Trifocal intraocular lenses: a comparison of the visual performance and quality of vision provided by two different lens designs.

PURPOSE: To compare two different diffractive trifocal intraocular lens (IOL) designs, evaluating longer-term refractive outcomes, visual acuity (VA) at various distances, low contrast VA and quality of vision. PATIENTS AND METHODS: Patients with binocularly implanted trifocal IOLs of two different designs (FineVision [FV] and Panoptix [PX]) were evaluated 6 months to 2 years after surgery. Best distance-corrected and uncorrected VA were tested at distance (4 m), intermediate (80 and 60 cm) and near (40 cm). A binocular defocus curve was collected with the subject's best distance correction in place. The preferred reading distance was determined along with the VA at that distance. Low contrast VA at distance was also measured. Quality of vision was measured with the National Eye Institute Visual Function Questionnaire near subset and the Quality of Vision questionnaire. RESULTS: Thirty subjects in each group were successfully recruited. The binocular defocus curves differed only at vergences of -1.0 D (FV better, P=0.02), -1.5 and -2.00 D (PX better, P<0.01 for both). Best distance-corrected and uncorrected binocular vision were significantly better for the PX lens at 60 cm (P<0.01) with no significant differences at other distances. The preferred reading distance was between 42 and 43 cm for both lenses, with the VA at the preferred reading distance slightly better with the PX lens (P=0.04). There were no statistically significant differences by lens for low contrast VA (P=0.1) or for quality of vision measures (P>0.3). CONCLUSION: Both trifocal lenses provided excellent distance, intermediate and near vision, but several measures indicated that the PX lens provided better intermediate vision at 60 cm. This may be important to users of tablets and other handheld devices. Quality of vision appeared similar between the two lens designs.

Toric intraocular lens orientation and residual refractive astigmatism: an analysis.

PURPOSE: To analyze intraocular lens (IOL) orientation data from an online toric back-calculator (astigmatismfix.com) for determining if differences were apparent by lens type. METHODS: A retrospective review of astigmatismfix.com toric back-calculations that included IOL identification and intended orientation axis. RESULTS: Of 12,812 total validated calculation records, 8,229 included intended orientation and lens identification data. Of the latter, 5,674 calculations (69%) involved lenses oriented 5° or more from their intended position. Using estimated toric lens usage data, the percentage of lenses with orientation ≥5° from intended was 0.89% overall, but the percentage varied significantly between specific toric lens brands (P<0.05). The percentage of back-calculations related to lenses that were not oriented as intended was also statistically significantly different by lens brand (P<0.05). When IOLs were misoriented, they were significantly more likely to be misoriented in a counterclockwise direction (P<0.05). This was found to be due to a bias toward counterclockwise orientation observed with one specific brand, a bias that was not observed with the other three brands analyzed here. CONCLUSION: The percentage of eyes with lens orientation ≥5° from intended in the Toric Results Analyzer data set was <1% of toric IOLs in general, with the relative percentage of Tecnis® Toric IOLs significantly higher than AcrySof® Toric IOLs. Both of these had higher rates than the Staar® Toric and Trulign® Toric lenses, with the availability of higher Tecnis and AcrySof cylinder powers a likely contributing factor. The AcrySof Toric IOL appears to be less likely than the Tecnis Toric IOL to cause residual astigmatism as a result of misorientation. The Tecnis Toric IOL appears more likely to be misoriented in a counterclockwise direction; no such bias was observed with the AcrySof Toric, the Trulign® Toric, or the Staar Toric IOLs.

Transzonular vitreous injection vs a single drop compounded topical pharmaceutical regimen after cataract surgery.

PURPOSE: To compare the relative effectiveness of a Tri-Moxi-Vanc intraocular solution injected transzonularly into the vitreous with the topical formulation of Pred-Moxi-Ketor (given for the first week postoperatively) followed by Pred-Ketor (given for weeks 2-4 after surgery). PATIENTS AND METHODS: This was a single-site, single-surgeon, prospective, randomized, subject-masked contralateral eye study with an active comparator and was approved by an appropriate ethics committee. Twenty-five subjects with uncomplicated cataract who were scheduled for cataract surgery were enrolled. If surgery was uneventful, subjects received either an injection in that eye or followed a minimum drop postoperative pharmaceutical regimen. The second eye surgery was performed with the opposite treatment. Subjects were followed for 1 month. Measures of interest were the changes in intraocular pressure (IOP) from baseline and the changes in corneal and macular thickness. Subjects were also asked to evaluate pain perception, visual quality, and overall satisfaction with surgery. They were also asked which regimen they preferred. RESULTS: IOP was not statistically significantly different between the groups (P=0.81); there was also no statistically significant difference in IOP over time (P=0.74). There was no statistically significant difference in central macular thickness at 1 week and 1 month between the groups (P=0.18). The central corneal thickness was significantly greater 1 day postoperatively relative to baseline, but there was no statistically significant difference between the groups at any time point (P=0.92). The difference in reported pain was also not statistically significantly different between the groups (P=0.67). Satisfaction with surgery was similar for both groups, but significantly more subjects preferred the injection for overall experience (P<0.01). CONCLUSION: Cataract surgery completed with the two pharmaceutical regimens was similar in outcome. Significantly more subjects preferred the injection, presumably as a function of the greater convenience with no apparent difference in the therapeutic effect.

Comparison of visual outcomes and subjective visual quality after bilateral implantation of a diffractive trifocal intraocular lens and blended implantation of apodized diffractive bifocal intraocular lenses.

PURPOSE: To compare the visual acuity (VA) and quality of vision between bilateral implantation of a trifocal intraocular lens (IOL) and blended bifocal IOLs with an intermediate add in the dominant eye and a near add in the nondominant eye. PATIENTS AND METHODS: Patients with either trifocal or blended bifocal IOLs implanted were recruited after surgery. Subjects returned for a single diagnostic visit between 3 and 24 months after surgery. VA was tested at various distances, including low-contrast acuity and acuity at their preferred reading distance. A binocular defocus curve was obtained, and subjective visual function and quality of vision were evaluated. RESULTS: Twenty-five trifocal subjects and 30 blended bifocal subjects were enrolled. There were no significant differences in low-contrast acuity, preferred reading distance, or acuity at that reading distance. Binocular vision at 4 m, 60 cm, and 40 cm was not statistically significantly different. The trifocal provided statistically significantly better visual acuity (P<0.05) at vergences from -0.5 to -1.5 D (from 2 m to 67 cm viewing distance, P<0.05). There was no statistically significant difference in the near vision subscale scores of the 39-question National Eye Institute Visual Function Questionnaire or the overall scores of the Quality of Vision questionnaire, though significantly more trifocal subjects reported that the observed visual disturbances were "bothersome" (P<0.05). CONCLUSION: Both lens modalities provided subjects with excellent binocular near and distance vision, with similar low rates of visual disturbances and good reported functional vision. The trifocal IOL provided significantly better intermediate VA in the viewing distance range of 2 m to 67 cm, corresponding to viewing things such as a car dashboard or grocery shelf. VA was similar between groups at viewing distances from 60 to 40 cm, corresponding to computer or reading distance.

Comparison of visual outcomes after implantation of diffractive trifocal toric intraocular lens and a diffractive apodized bifocal toric intraocular lens.

PURPOSE: The aim of this study was to compare a new diffractive trifocal toric lens with an apodized diffractive bifocal toric lens in terms of refractive and visual acuity (VA) outcomes, including low-contrast VA (LCVA), as well as the patient's visual function 3 months after implantation. PATIENTS AND METHODS: This is a randomized prospective study involving bilateral implantation of a trifocal toric or a bifocal toric lens. At 3 months postoperatively, the subject's vision was tested both uncorrected and with his/her best distance correction at: distance (4 m), intermediate (63 cm), and near (40 cm). Binocular defocus curves were measured with no correction and with the subject's best distance correction in place. Quality of vision was measured using the National Eye Institute Visual Function Questionnaire. RESULTS: A total of 22 patients were enrolled (eleven in each group). There was no statistically significant difference in the absolute change in measured rotation between 1 month and 3 months postoperatively between the two intraocular lens (IOL) groups (P=0.98). At 3 months, the postoperative refraction and distance VA by eye were similar between groups. There was no statistically significant difference in the measured LCVA between groups (P=0.39). The defocus curve showed that at 67 cm, the trifocal toric lens had statistically significantly better VA when compared to the bifocal toric lens. There were no statistically significant differences by group for any of the National Eye Institute Visual Function Questionnaire scores (P>0.26 in all cases). CONCLUSION: The trifocal toric IOL improved the intermediate vision without negatively impacting visual function and distance, near, or low-contrast VA when compared to a bifocal toric IOL. The toric component of the trifocal lens effectively reduced astigmatism and provided good rotational stability.

Retreatments after multifocal intraocular lens implantation: an analysis.

PURPOSE: To determine the incidence and etiology of required retreatment after multifocal intraocular lens (IOL) implantation and to evaluate the methods and clinical outcomes of retreatment. PATIENTS AND METHODS: A retrospective chart review of 416 eyes of 209 patients from one site that underwent uncomplicated cataract surgery with multifocal IOL implantation. Biometry, the IOL, and refractive data were recorded after the original implantation, with the same data recorded after retreatment. Comments related to vision were obtained both before and after retreatment for retreated patients. RESULTS: The multifocal retreatment rate was 10.8% (45/416 eyes). The eyes that required retreatment had significantly higher residual refractive astigmatism compared with those who did not require retreatment (1.21±0.51 D vs 0.51±0.39 D, P<0.01). The retreatment rate for the two most commonly implanted primary IOLs, blended bifocal (10.5%, 16/152) and bilateral trifocal (6.9%, 14/202) IOLs, was not statistically significantly different (P=0.12). In those requiring retreatment, refractive-related complaints were most common. Retreatment with refractive corneal surgery, in 11% of the eyes, and piggyback IOLs, in 89% of the eyes, was similarly successful, improving patient complaints 78% of the time. CONCLUSION: Complaints related to ametropia were the main reasons for retreatment. Residual astigmatism appears to be an important determinant of retreatment rate after multifocal IOL implantation. Retreatment can improve symptoms for a high percentage of patients; a piggyback IOL is a viable retreatment option.