Effect of Capsular Tension Ring on Rotational Stability of Loop-Haptic Intraocular Lens in Highly Myopic Patients.

To assess the effectiveness of prophylactic capsular tension ring (CTR) implantation during cataract surgery in highly myopic eyes. Eye and Ear, Nose, and Throat Hospital of Fudan University, Shanghai, China. Prospective cohort study. Consecutive highly myopic patients treated with cataract surgery were recruited and randomized to undergo CTR implantation or not. The outcomes compared between the 2 groups included axial lens position (ALP), intraocular lens (IOL) decentration and tilt, area of anterior capsule opening, severity of anterior capsular opacification (ACO), and posterior capsular opacification (PCO) at 1 year postoperatively. A total of 55 highly myopic eyes with CTRs implanted and 55 without were included in the analysis. At 1 year postoperatively, no significant differences were detected between the CTR and non-CTR groups for the mean ALP, IOL decentration, or tilt (all P > .05). However, the CTR group had a significantly larger area of anterior capsule opening (23.62 ± 3.30 mm2 vs 21.85 ± 2.30 mm2, P = .003), and less severe ACO (P = .033) and PCO (PCO-3 mm: 0.06 ± 0.13 vs 0.13 ± 0.20, P = .038; PCO-C: 0.15 ± 0.18 vs 0.25 ± 0.26, P = .026) than the non-CTR group. The corrected distance visual acuity, prediction error, and higher-order aberrations did not differ between the 2 groups (all P > .05). In highly myopic eyes, although prophylactic CTR implantation can reduce the severity of capsular contraction and opacification, it does not significantly affect postoperative IOL stability or visual outcomes.

Capsular tension ring (CTR) implantation has been shown to reduce intraocular lens (IOL) decentration and tilt in high myopia. However, the effect of CTR implantation in highly myopic eyes on IOL power calculation remains unclear, particularly in new-generation formulas. To evaluate the influence of CTR implantation on IOL power calculation in highly myopic eyes. This is a prespecified secondary analysis of outcomes of a randomized clinical trial conducted between November 2021 and September 2023 at the Zhongshan Ophthalmic Center in Guangzhou, China. Cataract patients with an axial length (AL) of 26 mm or longer were enrolled and stratified into 3 strata based on AL (stratum 1: AL 26-<28 mm; stratum 2: AL 28-<30 mm; stratum 3: AL ≥30 mm). Participants were stratified based on AL and randomized to the CTR group (a C-loop IOL combined with a CTR) or the control group (only a C-loop IOL) within each stratum. Predictive outcomes of 6 new-generation formulas and 4 traditional formulas were evaluated. The arithmetic and absolute prediction error (PE) and the percentages of eyes within ±0.25 diopter (D), ±0.50 D, ±0.75 D, and ±1.00 D of PE were analyzed. A total of 186 eyes of 186 participants were randomized into the CTR group (93 eyes [50%]) or control group (93 eyes [50%]). Excluding a withdrawal case and 24 eyes with best-corrected visual acuity less than 20/40, 80 eyes in the CTR group (86.0%) and 81 eyes in the control group (87.1%) were analyzed. Of 161 participants analyzed, overall mean (SD) participant age was 56.7 (10.5) years, and 100 participants (62.1%) were female. No differences were observed in arithmetic PE between the CTR and control groups in any strata. The CTR group showed smaller absolute PE in all new-generation formulas and higher percentage of PE within ±0.50 D in the Emmetropia Verifying Optical 2.0, Hoffer QST, LISA, and Pearl-DGS formulas only for eyes with an AL of 30 mm or longer compared with the control group. In traditional formulas, no differences were observed between the 2 groups in any strata. In this secondary analysis, CTR implantation in highly myopic eyes did not affect the target refraction and can improve the prediction accuracy of new-generation IOL calculation formulas in eyes with AL of 30 mm or longer. These findings support use of CTR implantation in eyes with an AL of 30 mm or longer. ClinicalTrials.gov Identifier: NCT05161520.

There is currently no consensus regarding the association of capsular tension ring (CTR) on intraocular lens (IOL) position or the indications for its implantation. To evaluate the association of CTR implantation on IOL position. PubMed, Embase, and Cochrane Library were searched from their inception to October 18, 2024. Randomized clinical trials (RCTs) or prospective cohorts reporting the effect or association of CTR on postoperative anterior chamber depth (ACD), IOL decentration, tilt, or rotation. Data extraction was conducted by 2 reviewers and verified by another for accuracy. Mean difference (MD) was used to synthesize the effect measures, and subgroup analyses were conducted according to IOL haptic design (C-loop and plate haptic) and whether the patient had high myopia. Postoperative ACD and IOL decentration, tilt, and rotation. A total of 11 RCTs and 7 cohort studies, involving 809 eyes with CTR and 822 eyes without CTR, were included in this meta-analysis. The analysis revealed that IOL tilt (MD, -1.04°; 95% CI, -2.05° to -0.03°; P = .04) and rotation (MD, -0.82°; 95% CI, -1.27° to -0.37°; P < .001) were smaller in the CTR group compared with the control group. The subgroup analysis of ACD (I2 = 70.7%; P = .03), decentration (I2 = 66.5%, P = .08), and tilt (I2 = 76.7%, P = .01) revealed a heterogeneity between the subgroups stratified according to IOL haptic design. Additionally, subgroup analysis demonstrated that CTR group showed a deeper ACD in eyes implanted with plate haptic IOLs (MD, 0.11 mm; 95% CI, 0.02 to 0.20 mm; P = .01), and a smaller IOL tilt in highly myopic eyes (MD, -1.43°; 95% CI, -2.59° to -0.26°; P = .02) compared with the control group. CTR implantation was associated with enhanced stability of IOL rotation in this meta-analysis, while only reducing IOL tilt in high myopia. While the direct clinical relevance of these results could not be determined from this investigation, these findings provide evidence supporting use of CTR implantation when toric IOLs have been implanted or with high myopia, although a hyperopic refractive shift after implantation of plate haptic IOLs may require target refraction adjustment.

To evaluate the influence of a capsular tension ring (CTR) on the intraocular lens (IOL)-capsule complex after cataract surgery in patients with long axial length. This was a prospective study. Patients underwent phacoemulsification and IOL implantation, with or without CTR implantation. Swept-source optical coherence tomography was performed at 1 day, 1 week, 1 month, and 3 months postoperatively to determine the postoperative aqueous depth (PAD), capsular bend index (CBI), and IOL tilt and decentration. Spherical equivalent values were obtained through subjective refraction and autorefraction. Root mean square was adopted to evaluate the indices listed above. Forty-three patients (56 eyes) were included in the study. Generalized estimating equation analysis of PAD showed a statistical difference between groups (P = .031). The RMS of the change in PAD was smaller in the CTR group than in the non-CTR group during the 3 months after surgery (P = .015). CBI in the CTR group increased more from 1 to 3 months after surgery than that in the non-CTR group (P = .025). The RMS of the change in vertical decentration was smaller in the CTR group than in the non-CTR group during the 3-month follow-up (P = .009). CTR implantation can stabilize the axial position of the IOL within the capsular bag after cataract surgery in patients with long axial length without affecting the refractive stability. The formation of capsular bend may be slightly delayed in the early stage after CTR implantation, but it accelerates from 1 to 3 months after surgery. [J Refract Surg. 2024;40(9):e654-e661.].

Capsular Tension Ring Use in High Myopic Eyes Undergoing Cataract Surgery: A Systematic Review and Meta-Analysis.

PurposeThe study investigated the effect of capsular tension ring (CTR) implantation on postoperative refractive stability and accuracy of intraocular lens (IOL) formulas for axial length (AL) ≥ 27.0 mm patients.MethodsProspective case series. The eyes of patients underwent phacoemulsification extraction combined with IOL implantation were classified as CTR implantation (A-CTR) and without CTR implantation (B-CON) groups. Refractive outcome and anterior chamber depth (ACD) were recorded at 1 week, 1 month, and 3 months post-operation. Prediction refractive error (PE) and absolute refractive error (AE) of each formula were calculated.ResultsA total of 89 eyes (63 patients) were included and randomized into the CTR (A-CTR) and control groups (B-CON). Comparison of refraction at different postoperative times of the CTR group showed no statistical difference (all P > 0.05). The ACD in the A-CTR group gradually deepened, and that in the B-CON group gradually shallowed (all P > 0.05). The formulas’ AE showed statistically significant differences in CTR and CON groups (P < 0.001). The PE of Hill-RBF 2.0 and EVO formulas in the A-CTR group were more hyperopic than that in the B-CON group (all P > 0.05), the other five formulas were more myopic in A-CTR group than that in the B-CON group (all P > 0.05).ConclusionPatients with 13 mm diameter CTR implantation tended to have stable refraction at 1 week post-surgery and 1 month for those without it. CTR of the 13 mm diameter had no effect on the selection of formulas. Additionally, it is found that Kane and EVO formulas were more accurate for patients with AL ≥ 27.0 mm.

Capsular tension rings (CTRs) can support weak zonules and inhibit capsular shrinkage, thus potentially reducing intraocular lens (IOL) decentration and tilt. However, it has been debated whether CTRs can reduce IOL decentration and tilt in highly myopic eyes and whether CTR implantation is necessary for all highly myopic eyes. To evaluate the influence of CTR implantation on IOL decentration and tilt in highly myopic eyes. This randomized clinical trial was conducted between November 2021 and September 2023 at the Zhongshan Ophthalmic Center, Guangzhou, China. Patients with cataract and an axial length (AL) of 26 mm or longer were enrolled. Participants were stratified into 3 groups based on the AL (stratum 1, 26 mm ≤ AL <28 mm; stratum 2, 28 mm ≤ AL <30mm; stratum 3, AL ≥30 mm), and further randomly assigned to the CTR group (a C-loop IOL combined with a CTR) or the control group (only a C-loop IOL) within each stratum. IOL decentration at 3 months after cataract surgery was evaluated using anterior segment optical coherence tomography. A total of 186 eyes of 186 participants (mean [SD] age, 57.3 [10.9] years; 118 female [63.4%]) were randomized into the CTR group (93 [50%]) or control group (93 [50%]), with 87 eyes (93.6%) and 92 eyes (98.9%) completing follow-up at 3 months, respectively. The CTR group showed smaller IOL decentration (0.19 mm vs 0.23 mm; difference, -0.04 mm; 95% CI, -0.07 to -0.01 mm; P = .02) and tilt at 3 months, and lower proportions of clinically significant IOL decentration (≥0.4 mm) and tilt (≥7°) at 3 months compared with the control group. Similar results were only found in eyes with an AL of 30 mm or longer (IOL decentration: 0.20 mm vs 0.28 mm; difference, -0.08 mm; 95% CI, -0.14 to -0.02 mm; P = .01). Additionally, the CTR group showed a smaller change in IOL decentration from 1 week to 3 months, higher prediction accuracy, and better visual quality and patient satisfaction in this stratum. No differences were observed between the CTR and control groups in eyes with an AL less than 30 mm. CTR implantation reduced C-loop IOL decentration and tilt, increased position stability, and improved visual quality in eyes with an AL of 30 mm or longer. These findings support use of CTR implantation in eyes with an AL of 30 mm or longer and implanted with C-loop IOLs. ClinicalTrials.gov Identifier: NCT05161520.

PurposeThe aim of the study is to evaluate the effect of capsular tension ring (CTR) implantation following cataract surgery on the refractive outcomes of patients with extreme high axial myopia.MethodsSixty eyes (with an axial length of ≥26 mm) were retrospectively reviewed and classified into two groups: CTR group (n = 30), which underwent CTR implantation following phacoemulsification, and control group (n = 30), which did not undergo CTR implantation. Intraocular lens (IOL) calculation was performed using Barrett Universal II (UII), Haigis, and SRK/T formulas. The refractive prediction error (PE) was calculated by subtracting the postoperative refraction from predicted refraction. The mean PE (MPE), mean absolute error (MAE), and percentages of eyes that had a PE of ±0.25, ±0.50, ±1.00, or ±2.00 diopters (D) were calculated and compared.ResultsNo significant differences were observed in PE between the two groups. The Barrett UII formula revealed a lower AE in the CTR group than in the control group (p = 0.015) and a lower AE than the other two formulas (p = 0.0000) in both groups. The Barrett UII formula achieved the highest percentage of eyes with a PE of ±0.25 D (66.67%).ConclusionsThe refractive outcomes were more accurate in eyes with CTR implantation than in those with routine phacoemulsification based on the Barrett UII formula. The Barrett UII formula was recommended as the appropriate formula when planning CTR implantation in high myopia.

To assess the contribution of capsular tension ring (CTR) to postoperative stability and visual outcomes of a plate-haptic toric intraocular lens (IOL). This prospective cohort study was performed among patients underwent toric IOL (AT TORBI 709M) implantation with or without CTR at the Eye and ENT hospital between April 2020 and November 2021. Propensity score matching (PSM) was performed to balance baseline factors. Postoperatively, uncorrected distance visual acuity (UCVA) and residual astigmatism, as well as IOLs' rotation, tilt, and decentration, were analyzed. Grouped multiple linear regression analysis was used to model predictive factors of rotation in each group. Additionally, a meta-analysis of data from 4 publications (284 eyes) and current study was performed to evaluate the effect of CTR co-implantation on toric IOL rotation. After PSM, 126 eyes from each group were included for further analysis. Postoperatively, UDVA was 0.31 ± 0.38 logMAR and 0.27 ± 0.36 logMAR in the CTR and NCTR groups, respectively (P = 0.441), and residual astigmatism was 0.75 ± 0.52 D and 0.86 ± 0.65 D, respectively (P = 0.139). The rotation of toric IOL was significantly smaller in the CTR group than in the NCTR group (4.63 ± 6.27 vs. 10.93 ± 16.05 degrees, P < 0.001). The regression models of the two groups and the coefficients of LT were significantly different (P < 0.001 and P = 0.001, respectively). Furthermore, the meta-analysis confirmed that CTR co-implantation reduced toric IOL rotation (MD, - 1.59; 95% CI, - 3.10 to - 0.09; P = 0.038). CTR enhances rotational stability of toric IOL by reducing the impact of LT, and CTR co-implantation is recommended in patients with lens thickness (LT) ≥ 4.5mm, white-to-white (WTW) ≥ 11.6mm, or high preexisting astigmatism.

BackgroundThe use of capsular tension ring (CTR) implantation to treat cataract patients with weak zonules is still controversial. The aim of this study was to examine the effects of CTR implantation on capsular stability after phacoemulsification in patients with weak zonules, especially patients who have undergone pars plana vitrectomy (PPV) or those who suffer from severe myopia.MethodsA total of 42 patients who underwent phacoemulsification and received an intraocular lens (IOL) were randomized to undergo CTR implantation or not. The control and CTR groups were compared in terms of uncorrected distant visual acuity (UDVA), best corrected distant visual acuity (BCDVA), refractive prediction error, the area of anterior capsulorhexis, and IOL inclination angle. Follow-up visits were conducted postoperatively at 1 day, 1 week, 1 month and 3 months. Subgroup analyses were performed based on PPV and severe myopia.ResultsSurgery significantly improved UDVA and BCDVA to similar extents in CTR and control patients, and refraction prediction error was similar between the two groups at all follow-up times. At 3 months after surgery, the area of anterior capsulorhexis was significantly larger in CTR patients than in controls (p = 0.0199). These differences were also significant between the subgroups of patients with severe myopia. Vertical IOL inclination was less within CTR groups at 3 months after surgery, especially in patients with severe myopia (p = 0.0286). At 1 week postoperatively, the proportion of individuals whose posterior lens capsule that had completely adhered to the posterior IOL surface was significantly higher among CTR patients (p = 0.023). No serious surgical complications were observed.ConclusionCTR implantation can benefit cataract patients with weak zonules by maintaining the shape of the capsular bag, reducing capsule shrinkage and stabilizing IOL inclination.Trial registrationChinese Clinical Trial Registry ChiCTR-INR-17011217, date of registration April 22, 2017, prospectively registered.

To investigate the effect of capsular tension ring (CTR) implantation on predicted refractive error after cataract surgery in patients with pseudoexfoliation (PEX) syndrome. This double-blind randomized clinical trial was conducted on 60 patients with PEX syndrome referring to Imam Khomeini Hospital affiliated to Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran, for undergoing cataract surgery. The study population was divided into two groups, namely CTR group (n=30) and non-CTR group (control group; n=30). The refractive error and anterior chamber depth (ACD) were measured 1wk, 1mo, and 3mo after phacoemulsification (PE) surgery. The results indicated no statistically significant difference between the two groups in terms of predicted refractive error (obtained by subtracting preoperative predicted refractive error from actual postoperative refractive error) 1wk (P=0.47), 1mo (P=0.30), and 3mo (P=0.06) after the PE surgery. Regarding the CTR group, the changes of ACD was statistically significant 1 and 3mo after the PE surgery, compared to those obtained 1wk post-surgery (P=0.005). The CTR implantation in PEX cataractous patients without zonulysis has no statistically significant effect on the predicted refraction and ACD changes after PE. The predicted refraction error has a hyperopic shift in both groups. The results reveal the unnecessary of calculating modified IOL in CTR implantation.

Patients with retinitis pigmentosa (RP) frequently exhibit zonular weakness, which poses challenges for intraocular lens (IOL) stability and refractive prediction. This study aimed to evaluate the impact of capsular tension ring (CTR) implantation on the predictive accuracy of 12 IOL power calculation formulas in patients with RP receiving cataract surgery. We conducted a retrospective cohort study where the predictive accuracy of 12 IOL formulas was assessed using refractive prediction error (PE), mean absolute error (MAE), root-mean-square absolute error (RMSAE), and the percentage of eyes achieving target refraction within ± 0.25 D to ± 1.00 D. These metrics were compared between eyes with (n = 23) and without (n = 30) CTR implantation. The influence of lens thickness (LT) on formula accuracy was also evaluated. In the overall cohort of 53 eyes from 38 patients with RP, the Barrett Universal II (BUII) formula yielded the lowest numerical MAE (0.45 D) and RMSAE (0.56 D), though none of the formulas were statistically superior in RMSAE. In the CTR group, significantly lower MAE was observed for Cooke K6 (P = 0.024), Kane (P = 0.016), Emmetropia Verifying Optical (EVO) 2.0 (P = 0.040), and PEARL-DGS (P = 0.021) compared to the non-CTR group. The CTR group also exhibited a significantly higher percentage of eyes within ± 0.50 D (P = 0.016), ± 0.75 D (P < 0.001), and ± 1.00 D (P < 0.001) of target refraction. Increasing LT correlated with a hyperopic shift for all formulas; however, BUII demonstrated relatively stable MAE across LT quartiles. Implantation of a CTR was associated with significantly improved predictive accuracy for several modern IOL formulas in patients with RP. The BUII formula showed the highest overall predictive accuracy.

To compare the rotational stability and visual outcomes of plate-haptic toric intraocular lenses (IOLs) with and without a capsular tension ring (CTR) in paired eyes. Eye and Ears, Nose, and Throat Hospital of Fudan University, Shanghai, China. Prospective, randomized, paired-eye study. Patients with bilateral cataracts and coexisting regular corneal astigmatism were enrolled. The 2 eyes of each patient were randomly assigned to the CTR or non-CTR (NCTR) group. Both eyes of each patient were subjected to phacoemulsification and toric IOL implantation. CTRs were implanted into the eyes of the CTR group. All patients were followed up for 12 months; uncorrected distance visual acuity (UDVA), residual astigmatism (RAS), and rotational degree of the toric IOL were recorded. 186 eyes of 93 patients were eligible for analysis. At each visit, UDVA improved significantly postoperatively in all eyes ( P < .001). The mean rotational degree and RAS were significantly smaller in the CTR group at the 2-week visit ( P < .05). The toric IOLs achieved rotational stability at 1 week postoperatively in the CTR group while at 2 weeks postoperatively in the NCTR group. In the subgroup analyses, CTR coimplantation significantly reduced the 2-week IOL rotation in eyes meeting specific ocular measurements. CTR coimplantation could increase the rotational stability of plate-haptic toric IOLs, by reducing the amount of IOL rotation in the early postoperative period and accelerating the stabilization of IOLs in the capsular bag.

PurposeTo evaluate the influence of a capsular tension ring (CTR) on rotational stability, decentration, tilt and axial stability of a 11.0mm plate haptic intraocular lens (IOL) DesignIntraindividual, randomized, double masked, controlled, clinical trial. ParticipantsPatients scheduled for sequential same day bilateral cataract surgery. MethodsAll patients were randomized to receive a CTR and a plate haptic IOL in one eye and a plate haptic IOL in the fellow eye only. IOL axis assessment was performed at the end of surgery (EOS), 1 hour (1h), 1 week (1w), 1 month (1m) and 6 months (6m) using a high precision evaluation method. Decentration and tilt of the crystalline and pseudophakic lenses were assessed preoperatively, at 1w and 6m using an anterior segment OCT (AS-OCT). Main outcome measuresRotational stability from EOS to 6m and at all follow up visits. Decentration and tilt at 6m. Differences in axial shift between 1w and 6m. ResultsOne hundred and thirty eyes of 65 patients were included in the study. Absolute rotation from EOS to 6m was 2.8°±3.9° and 3.2°±5.3° for the CTR and control groups, respectively (p=0.613). IOL decentration and IOL tilt at 6m were 0.29±0.1mm and 0.24±0.1mm and 6.7°±2.8° and 5.6°±1.6° for the CTR and control groups, respectively (p=0.058, p<0.01). A posterior IOL shift of 0.31±0.31 mm and 0.19±0.14 mm was observed in the CTR and control groups, respectively. ConclusionsConcomitant implantation of a CTR and a plate haptic IOL did not improve the overall rotational stability of the IOL compared to the control group. A negative effect of the CTR on decentration, tilt and axial stability was observed. The simultaneous use of a CTR and a plate haptic IOL in the absence of zonular weakness at the time of cataract surgery should be considered with caution.

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