The effect of Nd:YAG laser treatment of posterior capsule opacification on anterior chamber depth and refraction in pseudophakic eyes

Influence of Nd:YAG laser capsulotomy on toric intraocular lens rotation and change in cylinder power

PURPOSE

To investigate toric monofocal intraocular lens (TIOL) rotation and associated changes in cylinder power caused by Nd:YAG laser capsulotomy performed due to posterior capsule opacification (PCO).

SETTING

Ekol Eye Hospital, Izmir, Turkey.

DESIGN

Prospective case series.

METHODS

41 eyes of 20 women and 21 men were included in the study. Before and 1 month after Nd:YAG laser capsulotomy, TIOL tilt and decentration were determined with Scheimpflug camera, and TIOL axial rotation and the change in cylinder power induced by this rotation were measured by ray tracing aberrometry. The time interval between cataract surgery and Nd:YAG laser capsulotomy was noted.

RESULTS

Rotational misalignment of the TIOL was measured as 4.65 ± 2.75 degrees (range 0 to 11 degrees) before vs 6.97 ± 2.92 degrees (range 0 to 13 degrees) after capsulotomy, and absolute rotation was 2.75 ± 1.94 degrees (range 0 to 7 degrees, P = .028). Before and after Nd:YAG laser capsulotomy, cylinder power was 0.24 ± 0.70 diopter (D) (range 0.00 to 0.63 D) vs 0.56 ± 0.77 D (range 0.02 to 0.91 D), respectively, with an absolute change in cylinder power of 0.34 ± 0.22 D (range 0.01 to 0.90 D, P = .001). After capsulotomy, there was a significant decrease in IOL tilt in the horizontal and vertical planes and an increase in decentration ( P < .05). Time interval (33.02 ± 12.9 months) and IOL horizontal decentration were independent factors affecting IOL rotation after capsulotomy ( P < .05).

CONCLUSIONS

Nd:YAG laser capsulotomy may cause TIOL rotation as well as tilt and decentration, resulting in a change in the TIOL's corrective effect on corneal astigmatism. Although this change was clinically insignificant, it may be beneficial to consider that TIOL rotational misalignment may occur in patients undergoing early capsulotomy.

Refractive Changes After Nd:YAG Capsulotomy in Pseudophakic Eyes

Purpose

To analyze refractive changes after neodymium: yttrium-aluminum-garnet (Nd:YAG) posterior capsulotomy in pseudophakic eyes.

Patients and Methods

Patients who underwent Nd:YAG capsulotomy after cataract surgery from January 2013 to April 2022 were included in this retrospective study. Sphere, cylinder, spherical equivalent (SE), axis, and corrected distance visual acuity (CDVA) were compared pre- and postoperatively in 683 eyes of 548 patients at one month (n = 605 eyes) and one year (n = 211 eyes). Patients with both one-month and one-year follow-ups (n = 133) were also compared. Eyes were stratified into single-piece (n = 330), three-piece (n = 30), and light adjustable lenses (LALs) (n = 16). Pre- and postoperative measurements were analyzed within each group.

Results

Cylinder was significantly decreased at one-month (difference: 0.042±0.448 D, p = 0.006) and one-year (difference: 0.101±0.455 D, p = 0.003) compared to preoperative measurements. No significant change in sphere or axis was observed at follow-up visits (p > 0.05). CDVA significantly improved at both time points (p < 0.05). No significant change in any parameters between the one-month and one-year groups was observed (p > 0.05). There was significant improvement in CDVA in the single and three-piece lens groups (p < 0.0001 and p = 0.026, respectively), with no change in the LAL group (p > 0.05).

Conclusion

There were no changes in sphere, axis, or spherical equivalent after Nd:YAG capsulotomy. However, cylindrical error and CDVA were significantly better after the procedure. Lens type did not impact refractive parameters postoperatively.

Refraction Shift After Nd:YAG Posterior Capsulotomy in Pseudophakic Eyes: A Systematic Review and Meta-analysis

PURPOSE

To explore ocular refraction shift after Neodymium: yttrium aluminum garnet (Nd:YAG) posterior capsulotomy in pseudophakic eyes.

METHODS

A systematic literature search was performed in the PubMed, Embase, and Cochrane Library databases until November 10, 2021. Studies on the evaluation of changes in spherical equivalent (SE), cylindrical error (CE), or anterior chamber depth (ACD) after Nd:YAG laser capsulotomy were included in the meta-analysis. The review was registered in the international platform of registered systematic review and meta-analysis protocols (INPLASY202120059).

RESULTS

A total of 805 eyes from 18 studies were included in the final analysis. The pooled mean differences in SE from baseline to postoperative follow-up points were not significant (1 hour: 0.04 diopters [D], 95% CI: -0.13 to 0.21, P = .644; 1 week: 0.04 D, 95% CI: -0.12 to 0.20, P = .640; 1 month: 0.05 D, 95% CI: -0.06 to 0.16, P = .349). There was no significant difference between baseline CE and any subsequent visit (1 week: 0.14 D, 95% CI: -0.06 to 0.33, P = .172; 1 month: 0.17 D, 95% CI: -0.04 to 0.38, P = .108). No statistical difference in ACD from baseline was observed either (1 hour: 0.01 mm, 95% CI: -0.07 to 0.09, P = .846; 1 week: -0.12 mm, 95% CI: -0.24 to 0.01, P = .079; 1 month: -0.06, 95% CI: -0.14 to 0.01, P = .110).

CONCLUSIONS

Neither ocular refraction nor ACD changed within 1 month after laser capsulotomy, suggesting laser capsulotomy did not affect ocular refraction in short-term observation. [J Refract Surg. 2022;38(7):465-473.].

Intraocular Lens Position and Anterior Chamber Parameters Evaluation After Nd:YAG Laser Posterior Capsulotomy for Posterior Capsular Opacification Using Anterior Segment Swept-Source Optical Coherence Tomography

Purpose

Patients and Methods

Results

Conclusion

Short-Term Anterior Segment Changes After Nd-YAG Laser Posterior Capsulotomy in Pseudophakic Eyes with Fuchs' Endothelial Dystrophy

Purpose

To describe the changes in the central corneal thickness (CCT), endothelial cell count (ECC), intraocular lens (IOL) position, and refractive error 1 and 3 months after Nd-YAG laser posterior capsulotomy (YAG-PC) for posterior capsular opacification (PCO) in pseudophakic eyes with Fuchs' endothelial cell dystrophy (FECD).

Design

Prospective case-control.

Participants

Fifty pseudophakic eyes of 50 patients with visually significant PCO (25 with healthy corneas, and 25 with FECD grade 1 and 2).

Methods

FECD was clinically graded, and only patients without clinically evident corneal edema were included in the study (grade 1 and 2). All patients received YAG-PC and were followed up after 1 and 3 months. Best-corrected visual acuity, refractive errors, ACD, CCT, and ECC were assessed and compared between the pre-laser values and that of the 2 follow-up visits.

Results

In both groups, BCVA showed significant improvement (P<0.05). Compared to healthy controls, a significant hyperopic shift was observed in the FECD eyes at the 2 follow-up visits (P=0.027, and 0.019). A significant backward movement of the IOL was observed in the FECD eyes in the 2 follow-up visits (P=0.043, and 0.02). There was a significant correlation between the hyperopic shift in the FECD eyes and the ACD deepening during the 1st month (R= -0.6, P=0.001) and 3rd month (R= -0.4, P=0.04). Significant drop in the ECC was noted in both groups but without significant increase in the CCT.

Conclusion

Compared to controls, a hyperopic shift and backward movement of the IOL were observed in the FECD eyes after YAG-PC. No significant corneal thickening was found in both groups despite the significant drop in the ECC. Future studies are required to confirm our results and monitor the long-term changes after YAG-PC in FECD.

Influence of the "Inverted U Method" Nd: YAG Laser Posterior Capsulotomy on Anterior Segment Parameters, Decentration and Tilt of Intraocular Lens in Patients after Phaco-vitrectomy

PURPOSE

To investigate the effects of the "inverted U method" Nd:YAG laser posterior capsulotomy on anterior segment parameters, decentration and tilt of intraocular lens (IOLs) and visual acuity in posterior capsular opacification (PCO) patients after combined phaco-vitrectomy.

METHODS

Seventy-six patients (76 eyes) were enrolled in this study, who were diagnosed as PCO and underwent "inverted U method" Nd:YAG laser posterior capsulotomy. All patients had undergone previous combined phaco-vitrectomy for rhegmatogenous retinal detachment. The parameters including IOL decentration, angle of IOL tilt, anterior chamber angle (ACA), anterior chamber depth (ACD), anterior chamber volume (ACV), central corneal thickness (CCT), keratometry, pupil size, axial length (AL), intraocular pressure (IOP), refractive status, corrected distance visual acuity (CDVA), objective scattering index (OSI) and Chinese version of Visual Function 14 (VF-14) index were obtained before and 3 months after capsulotomy.

RESULTS

After capsulotomy, the tilt angle and decentration of the IOLs at both vertical (tilt: p = .004, decentration: p = .029) and horizontal meridian (tilt: p = .001, decentration: p = .017) were significantly decreased, ACA increased (p = .015), CDVA (p = .000), VF-14 score (p = .000) and OSI (p = .000) were significantly improved. There were a significant decrease in cylindrical error (p = .001) and a myopic shift in spherical error (p = .001) after the capsulotomy. No significant differences in ACD, ACV, CCT, keratometry, pupil size, AL and IOP were detected (p > .05 for all).

CONCLUSION

The "inverted U method" Nd: YAG laser posterior capsulotomy decreases tilt and decentration of the IOL, increases ACA and causes no change in ACD, ACV, CCT and IOP in patients after phaco-vitrectomy. These changes make a decrease in cylindrical error and a myopic shift in spherical error. Laser capsulotomy significantly improves visual acuity.

Utility of the optical quality analysis system for decision-making in Nd: YAG laser posterior capsulotomy in patients with light posterior capsule opacity

Background

A prospective cohort study was performed to evaluate whether the Optical Quality Analysis System (OQAS) can serve as a valuable additional indicator for appropriate posterior capsulotomy referral.

Methods

One hundred and five eyes from 96 patients undergoing capsulotomy were divided into precapsulotomy logMAR CDVA ≤0.1 group and logMAR CDVA > 0.1 group. CDVA, and the Visual Function 14 index (VF-14) score were estimated before and 1 month after capsulotomy. The objective scattering index (OSI) value was measured by using the OQAS. Posterior capsule opacification (PCO) severity was assessed with Evaluation of PCO 2000 (EPCO 2000) software.

Results

In logMAR CDVA > 0.1 group, the correlations of OSI, logMAR CDVA, EPCO score and VF-14 score were very strong preoperatively. In logMAR CDVA ≤0.1 group, preoperatively, OSI was correlated with logMAR CDVA (r = 0.451), EPCO score (r = 0.789), and VF-14 score (r = 0.852). LogMAR CDVA has weak correlation with VF-14 score (r = − 0.384) and EPCO score (r = 0.566). VF-14 score was correlated with EPCO score (r = − 0.669). In the logMAR CDVA ≤0.1 group, there was no significant difference in logMAR CDVA between precapsulotomy and postcapsulotomy (P > 0.05). In the two groups, all the other optical quality parameters were significantly improved after capsulotomy (P < 0.05). In logMAR CDVA > 0.1 group, the area under the curve of the ROC of the OSI was 0.996 (P = 0.000). In logMAR CDVA ≤0.1 group, the area under the curve of the ROC of the OSI was 0.943 (P = 0.000).

Conclusions

The OSI was useful for evaluating of PCO and prediction of beneficial capsulotomy. Especially for patients with slight PCO and better visual acuity, OSI is more valuable than CDVA and completely objective examination.

Trial registration

The study protocol was registered at the Chinese Clinical Trial Registry. Register: ChiCTR1800018842 (Registered Date: October 13th, 2018).

Therapeutic Ophthalmic Lenses: A Review

An increasing incidence of eye diseases has been registered in the last decades in developed countries due to the ageing of population, changes in lifestyle, environmental factors, and the presence of concomitant medical conditions. The increase of public awareness on ocular conditions leads to an early diagnosis and treatment, as well as an increased demand for more effective and minimally invasive solutions for the treatment of both the anterior and posterior segments of the eye. Despite being the most common route of ophthalmic drug administration, eye drops are associated with compliance issues, drug wastage by lacrimation, and low bioavailability due to the ocular barriers. In order to overcome these problems, the design of drug-eluting ophthalmic lenses constitutes a non-invasive and patient-friendly approach for the sustained drug delivery to the eye. Several examples of therapeutic contact lenses and intraocular lenses have been developed, by means of different strategies of drug loading, leading to promising results. This review aims to report the recent advances in the development of therapeutic ophthalmic lenses for the treatment and/or prophylaxis of eye pathologies (i.e., glaucoma, cataract, corneal diseases, or posterior segment diseases) and it gives an overview of the future perspectives and challenges in the field.

Intraocular lens tilt and decentration after Nd:YAG laser posterior capsulotomy: Femtosecond laser capsulorhexis versus manual capsulorhexis

PURPOSE

To compare intraocular lens (IOL) tilt and decentration after Nd:YAG laser posterior capsulotomy in eyes that had femtosecond laser-assisted capsulotomy versus manual capsulorhexis.

SETTING

Ekol Eye Hospital, Izmir, Turkey.

DESIGN

Retrospective case series.

METHODS

Intraocular lens decentration and angle of tilt were measured using a Scheimpflug camera before and 1 month after Nd:YAG capsulotomy.

RESULTS

Eighteen eyes had a femtosecond laser-assisted capsulotomy and 25 eyes a manual capsulorhexis. The mean age was 58.2 years ± 10.2 (SD) (range 44 to 69 years) and 60.6 ± 8.3 years (range 45 to 70 years), respectively. Before capsulotomy, the angle of tilt and decentration at both meridians did not differ significantly between the 2 groups (P > .05). After capsulotomy, the angle of tilt was significantly decreased in both groups (femtosecond: vertical 1.5 degrees and horizontal 1.2 degrees; manual: vertical 1.1 degrees and horizontal) and decentration was significantly increased (femtosecond: vertical 0.085 mm and horizontal 0.096 mm; manual: vertical 0.2 mm and horizontal 0.2 mm) at both meridians (P < .05). After capsulotomy, all tilt and decentration parameters were significantly different between the 2 groups (P < .05) except decentration on the horizontal meridian (P = .669).

CONCLUSIONS

Nd:YAG posterior capsulotomy performed after femtosecond laser-assisted capsulotomy resulted in better mechanical stability of the IOL. This suggests that a femtosecond laser-created capsulotomy better maintains a proper IOL position. Although the differences were statistically significant, the tilt and decentration values were small and might not be clinically significant.

Imaging of Age-Related Macular Degeneration by Adaptive Optics Scanning Laser Ophthalmoscopy in Eyes With Aged Lenses or Intraocular Lenses

Purpose

To assess the performance of adaptive optics scanning laser ophthalmoscopy (AOSLO) in a large sample of eyes with or without age-related macular degeneration (AMD) and with cataracts or intraocular lenses (IOLs).

Methods

Patients with various degrees of AMD and age-similar normal subjects underwent fundus photography. Cataract severity and IOL clarity were assessed by fundus reflex photographs. In phakic eyes, lenticular opacity was graded as nuclear, cortical, or posterior subcapsular cataract. In eyes with IOLs, lens clarity was assessed by posterior capsule opacification (PCO). Quality of AOSLO images of the macular photoreceptor mosaic was classified as good, adequate or inadequate by human graders in a subjective assessment of cone visibility.

Results

A total of 159 eyes in 80 subjects (41 males, 39 females, aged 72.5 ± 11.5 years, 16 normals) were examined. Seventy-nine eyes had IOLs, and 80 eyes were phakic. AOSLO produced good images in 91 eyes (57%), adequate images in eight eyes (5%), and inadequate images in 27 eyes (17%). AOSLO did not acquire images in 33 eyes (21%), because of dense lenticular opacity, widespread PCO, or problems specific to individual subjects.

Conclusions

AOSLO images considered at least Adequate or better for visualizing cone photoreceptors were acquired from 62% of study eyes.

Translational Relevance

AOSLO can be used as an additional imaging modality to investigate the structure of cone photoreceptors in research on visual function in AMD and in clinical trials involving older patients.

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.

Evaluation of the anterior segment parameters after Nd: YAG laser Capsulotomy: Effect the design of intraocular lens Haptic

Objective:

To evaluate the changes in anterior segment parameters after neodymium–yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy in 1-piece and 3-piece IOLs.

Methods:

In an institution, 65 eyes of 65 consecutive pseudophakic patients with posterior capsule opacification underwent Nd:YAG laser capsulotomy. The patients were divided into two groups according to the IOL type. Group-1 consisted of 35 subjects with 1-piece IOL and Group-2 consisted of 30 subjects with 3-piece IOL. Anterior segment parameters were measured with the Sirius rotating camera before, one week and one month after Nd:YAG laser capsulotomy.

Results:

Mean age was 72.3±5.2 years in 1-piece IOL and 72.3±6.8 years in 3-piece IOL. There were no statistically significant differences before capsulotomy for IOP, axial length, spherical equivalent, anterior chamber depth, central corneal thickness, anterior chamber angle and anterior chamber volume between two IOL groups. BCVA improved after capsulotomy in both groups (p=0.001). Both IOL groups had statistically significant myopic shift compared with the baseline values (P= 0.03 and P=0.01 resp.). Both IOL groups had statistically significant decrease in ACD, from baseline to the 1st week and 1^st month (p=0.04 and 0.03 resp.).

Conclusion:

To achieve the highest percentage of refractive and anterior segment stability surgeons may prefer to implant the 1-piece IOL design.

Comparative study of induced changes in effective lens position and refraction after Nd:YAG laser capsulotomy according to intraocular lens design

Purpose

To evaluate and compare the changes in refraction and effective intraocular lens (IOL) position between a plate-haptic IOL and a c-loop single-piece IOL after neodymium-doped yttrium aluminium garnet (YAG) laser posterior capsulotomy.

Methods

In a prospective study, anterior chamber depth and subjective refraction were measured in 110 pseudophakic eyes from 110 patients, before and 1 month after YAG laser capsulotomy. Patients were divided into 2 groups according to the IOL design: group 1 (plate-haptic acrylic hydrophilic AT LISA tri 839MP^®) and group 2 (c-loop acrylic hydrophobic single-piece AcrySof^® SA60AT). Lens position was obtained through optical coherence biometry (Biograph WaveLight OB820^®).

Results

YAG laser capsulotomy was performed 37.8±9.8 months after surgery in group 1 and 40.6±8.6 months in group 2 (p=0.125). Significant changes were found in the lens effective position after treatment in the 2 groups. The YAG posterior capsulotomy led to a change of anterior chamber depth in group 1 from 4.03±0.32 mm to 3.86±0.34 mm (p=0.02) and in group 2 from 4.03±0.37 mm to 4.14±0.45 mm (p=0.025). After YAG laser posterior capsulotomy, no significant changes were observed in mean spherical equivalent, sphere or cylinder for both groups (p>0.05).

Conclusion

YAG laser posterior capsulotomy can induce a significant change in the IOL position according to the IOL type; however, the refractive change after treatment is clinically insignificant.

Comparison of two Nd:YAG laser posterior capsulotomy: cruciate pattern vs circular pattern with vitreous strand cutting

AIM

To investigate the effects and safety of neodymium: yttrium-aluminium-garnet (Nd:YAG) laser posterior capsulotomy with vitreous strand cutting.

METHODS

A total of 40 eyes of 37 patients with symptomatic posterior capsular opacity (PCO) were included in this prospective randomized study and were randomly subjected to either cruciate pattern or round pattern Nd:YAG posterior capsulotomy with vitreous strand cutting (modified round pattern). The best corrected visual acuity (BCVA), intraocular pressure (IOP), refractive error, endothelial cell count (ECC), anterior segment parameters, including anterior chamber depth (ACD) and anterior chamber angle (ACA) were measured before and 1mo after the laser posterior capsulotomy.

RESULTS

In both groups, the BCVA improved significantly (P<0.001 for the modified round pattern group, P=0.001 for the cruciate pattern group); the IOP and ECC did not significantly change. The ACD significantly decreased (P<0.001 for both) and the ACA significantly increased (P=0.001 for the modified round pattern group and P=0.034 for the cruciate group). The extent of changes in these parameters was not significantly different between the groups.

CONCLUSION

Modified round pattern Nd:YAG laser posterior capsulotomy is an effective and safe method for the treatment of PCO. This method significantly changes the ACD and ACA, but the change in refraction is not significant. Modified round pattern Nd:YAG laser posterior capsulotomy can be considered a good alternative procedure in patients with symptomatic PCO.