Intraocular Pressure Spikes following Neodymium-doped Yttrium Aluminum Garnet Laser Capsulotomy: Current Prevalence and Management in Israel

Neodymium-doped yttrium aluminum garnet (Nd: YAG) laser treatment in ophthalmology: a review of the most common procedures Capsulotomy and Iridotomy

Nowadays, lasers are used in various medical fields. Ophthalmology was the first medical specialty to utilize lasers in patient treatment and still remains the leading medical field that uses laser energy for both therapeutic and diagnostic purposes. The neodymium: yttrium-aluminum-garnet (Nd: YAG) laser is one of the most common lasers used in ophthalmology. It is a solid-state laser with a wavelength of 1064 nm that works on the principle of photodisruption. Since its introduction in ophthalmology over 40 years ago, it has found various applications, mainly for procedures where cutting or disruption of ocular tissue is required. Compared to surgical alternatives, the use of Nd: YAG lasers on ocular tissue is minimally invasive. In this review, we focus on the two most common ophthalmic applications of Nd: YAG laser - laser peripheral iridotomy and posterior capsulotomy. The history of the techniques, current trends, potential complications, and the prognosis for future use is discussed.

Intraocular pressure changes during intravitreal aflibercept injection based on treat-and-extend regimen in Japanese patients with neovascular age-related macular degeneration and glaucoma

PURPOSE

To assess the changes in intraocular pressure (IOP) after intravitreal aflibercept injections in Japanese patients with neovascular age-related macular degeneration (nAMD) complicated by glaucoma.

STUDY DESIGN

Retrospective observational study.

METHODS

We retrospectively reviewed 27 eyes of 25 Japanese patients diagnosed with nAMD complicated by glaucoma. The patients were treated with 2 mg/0.05 ml of aflibercept and followed for 52 weeks according to a treat-and-extend (TAE) regimen after 3 consecutive monthly injections. The IOP of each eye was measured at each visit using non-contact tonometry. IOP changes as well as additional glaucoma treatments during 52 weeks were recorded.

RESULTS

The mean of aflibercept injections was 8.3 ± 1.9. The mean IOP at baseline was 14.0 ± 3.1 mmHg, and the mean IOP after aflibercept therapy was 13.0 ± 2.4 mmHg at the final visit (P = 0.0463). No patients received additional glaucoma treatment of eye drops or surgery.

CONCLUSION

Our results suggest that intravitreal aflibercept injections may be beneficial for patients with nAMD complicated by glaucoma.

The complication rate following Neodymium-doped Yttrium Aluminum Garnet laser posterior capsulotomy for posterior capsular opacification in patients with and without comorbidities

Purpose

To study the complication rate following Nd: YAG posterior capsulotomy posterior capsular opacification (PCO) in patients with and without comorbid conditions.

Methods

This was a prospective, interventional, comparative, and observational study. A total of 80 eyes, consisting of 40 eyes without ocular comorbidities (group A) and 40 eyes with ocular comorbidities (group B) that were being treated with Nd: YAG capsulotomy for PCO, were included. Visual outcome and complications of Nd: YAG capsulotomy were studied.

Results

The mean age of group A patients was 61.65 ± 8.85 years and that of group B patients was 63 ± 10.46 years. Of the total, 38 (47.5%) were men and 42 (52.5%) were women. In group B, the ocular comorbidities were moderate nonproliferative diabetic retinopathy (NPDR) (n = 14 eyes; 14/40 = 35%), subluxated intraocular lens (IOL; <2 clock hours of subluxation; n = 6), age-related macular degeneration (ARMD; n = 6), post-uveitic eyes (having old signs of uveitis, no episode of uveitis since the last 1 year; n = 5), and operated cases of traumatic cataract (n = 4). The mean energy required in groups A and B was 46.95 ± 25.92 and 42.62 ± 21.85 mJ, respectively (P = 0.422). The average energy requirement in Grade 2, Grade 3, and Grade 4 PCO was 22.30, 41.62, and 79.52 mJ, respectively. An increase in intraocular pressure (IOP) of >5 mmHg from pre-YAG levels was observed in one patient in each group on day 1 postprocedure, for which medical treatment was given to both patients for 7 days. One patient in each group had IOL pitting. No patient had any other complications attributable to ND:YAG capsulotomy.

Conclusion

Nd:YAG laser posterior capsulotomy is a safe procedure for PCO in patients with comorbidities. Visual outcomes were excellent after Nd:YAG posterior capsulotomy. Although a transient increase in IOP was noted, the response to treatment was good and a long-term increase in IOP was not observed.

Refractive Changes Following Premature Posterior Capsulotomy Using Neodymium:Yttrium–Aluminum–Garnet Laser

We aimed to determine the timing of neodymium:yttrium–aluminum–garnet (Nd:YAG) laser capsulotomy on corrected-distance visual acuity (CDVA), intraocular pressure (IOP), and spherical equivalent (SE) in patients with posterior capsular opacification (PCO). There were 59 patients with unilateral PCO and a history of Nd:YAG laser capsulotomy enrolled and further divided into the early Nd:YAG group (timing < 12 months, n = 25) and late Nd:YAG group (timing > 12 months, n = 34) depending on the elapsed months from phacoemulsification to Nd:YAG laser capsulotomy. The primary outcomes were CDVA, IOP, and SE before (immediately before Nd:YAG laser capsulotomy) and after (weeks one and four after the laser treatment). The independent t test was applied to analyze the difference in CDVA, IOP, and SE between the two groups, while the generalized estimating equation with Bonferroni adjustment was conducted to evaluate the effect of all the parameters on the change in SE with adjusted odds ratio (aOR) and 95% confidence interval (CI). The CDVA showed significant improvement in both the early Nd:YAG group (p = 0.005) and the late Nd:YAG group (p = 0.001), and hyperopic change occurred in both the early Nd:YAG group (p = 0.003) and the late Nd:YAG group (p = 0.017). The early Nd:YAG group revealed more significant hyperopic change compared with the late Nd:YAG group four weeks after Nd:YAG treatment (p < 0.001), which was still significant after multivariable analysis (aOR: 0.899, 95% CI: 0.868–0.930, p = 0.011). In addition, a deeper ACD (aOR: 0.764, 95% CI: 0.671–0.869, p = 0.019) was significantly correlated with hyperopic change. In conclusion, Nd:YAG laser capsulotomy performed within one year after cataract surgery may lead to significant hyperopic change, in which the ACD alteration affects the hyperopic shift significantly.

Corneal Endothelial Changes Following Early Capsulotomy Using Neodymium:Yttrium-Aluminum-Garnet Laser

We aimed to survey whether the timing of neodymium:yttrium–aluminum–garnet (Nd:YAG) laser capsulotomy would alter the corneal endothelial morphology and density. A retrospective cohort study was conducted, and 48 patients with unilateral posterior capsular opacity (PCO) and Nd:YAG laser capsulotomy performance were enrolled. The participants were divided into the early Nd:YAG group (timing ≤ 12 months, n = 20) and late Nd:YAG group (timing > 12 months, n= 28) depending on elapsed months between phacoemulsification and Nd:YAG laser capsulotomy. Endothelial cell density (ECD), coefficient of variant (CV), hexagonality (HEX), and central corneal thickness (CCT) between the two groups were collected. A generalized estimate equation was conducted to evaluate the corneal endothelial parameters between the two groups with an adjusted odds ratio (aOR) and 95% confidence interval (CI). The CDVA was improved after treatment in both groups (both p < 0.001). Chronically, ECD in the early group was significantly decreased one week after treatment (2221.50 ± 327.73/mm² vs. 2441.55 ± 321.80/mm², p < 0.001), which recovered to 2369.95 ± 76.37/mm² four weeks after the treatment but was still lower than the preoperative status (p < 0.001). In addition, the HEX percentage showed a significant reduction at four weeks after treatment (p = 0.028). The ECD in the early group was significantly lower than that in the late group (aOR: 0.167, 95% CI: 0.079–0.356, p = 0.003) in both week 1 (p < 0.001) and week 4 (p = 0.004) after laser treatment. In conclusion, the early application of Nd:YAG laser capsulotomy within one year after cataract surgery may be the reason for postoperative ECD decrement without known etiology.

Long-term effects of intravitreal bevacizumab and aflibercept on intraocular pressure in wet age-related macular degeneration

Background

To evaluate the incidence of sustained elevation of intraocular pressure (SE-IOP) associated with intravitreal injections of anti-vascular endothelial growth factors (anti-VEGF) bevacizumab and aflibercept in patients with wet age-related macular degeneration (wAMD).

Methods

A retrospective cohort study consisting of 120 eyes from 120 patients with anti-VEGF treatment for wAMD. Three different anti-VEGF groups were considered: i) 71 cases receiving bevacizumab only, ii) 49 cases receiving bevacizumab before switch to aflibercept, iii) 49 cases after switch to aflibercept. 120 uninjected fellow eyes served as controls. SE-IOP was defined as an increase from baseline ≥5 mmHg on 2 consecutive follow-up visits. The incidence of SE-IOP was analysed using exact Poisson tests and survival analysis. The time course of IOP was evaluated with linear mixed effect modelling.

Results

In total, 6 treated eyes (2.38% incidence per eye-year) and 9 fellow eyes (3.58% incidence per eye-year) developed SE-IOP, and survival analysis showed no statistically significant difference (p = 0.43). Furthermore, the incidence of SE-IOP did not differ between the three anti-VEGF groups. Comparing the injected eyes of patients under 70 years to those of patients over 70 years, there was a statistically significant difference in survival without SE-IOP (incidence of 16.7% vs 0.7%, respectively, p < 0.0001).

Conclusion

Intravitreal anti-VEGF injections were not associated with sustained elevation of IOP. These results do not support the claim that repeated anti-VEGF injections could elevate IOP.

Study of Intraocular Pressure following Neodynium Yttrium Aluminium Garnet Laser Capsulotomy with the Use of Brimonidine: A Descriptive Cross-sectional Study

Introduction:

Posterior capsular opacification is a common complication after cataract surgery. Neodynium Yttrium Aluminium Garnet laser capsulotomy is still the preferred treatment for posterior capsular opacification. This study was done to determine the use of Brimonidine eye drop in preventing the rise of intraocular pressure post-Neodynium Yttrium Aluminium Garnet laser capsulotomy.

Methods:

A descriptive cross-sectional study was conducted in Lumbini eye institute and research center, Bhairahawa, Nepal, in 200 eyes with posterior capsular opacification using Brimonidine from Feb 1, 2019, to July 30, 2019. The Institutional Review Committee approved the study with approval number 0237. A convenient sampling method was used. Pre-capsulotomy best-corrected visual acuity, slit-lamp examination of the anterior segment, and dilated fundus examination were done. Intraocular pressure was measured with Goldmann Applanation Tonometer. Post capsulotomy patients were evaluated after one hour, two hours, and two weeks for intraocular pressure and any complications. The statistical analysis was done using Statistical Package of Social Sciences version 20.0 statistical analysis software. The descriptive statistical analysis of the study was done after the collection of the data.

Results:

Mean age of patients at presentation was 61.61 ±SD 1.09. The mean intraocular pressure following Neodynium Yttrium aluminum garnet laser capsulotomy using brimonidine at 1 hour was 12.73±3.3 mmHg. and two hours was 11.98±3.2 mmHg. The mean energy per pulse was 2.3 ±SD 0.3 mJ. The mean duration of posterior capsular opacification from cataract surgery was 22.28 weeks.

Conclusions:

Neodynium Yttrium Aluminium Garnet laser capsulotomy had lower intraocular pressure after the Brimonidine eye drop procedure. The maximum mean reduction in intraocular pressure was observed after two hours.

Effect of Anticoagulants and Surgeon-Related Factors on Short-term Outcomes of Laser Peripheral Iridotomy

PURPOSE

To assess the effects of surgeon-related factors on laser peripheral iridotomy (LPI) outcomes by comparing residents and glaucoma specialists, and to look for demographic and clinical predictive factors associated with LPI complications.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients who underwent LPI performed by a resident physician were included as cases, and patients who underwent LPI performed by a glaucoma specialist were included as controls. In patients who underwent multiple sessions of laser therapy, only the information from the first session of each eye was included in the study.

METHODS

Demographic and clinical information were gathered from the pre-LPI, 1-week, 1-month, and 3-month follow-up visits. The following information was recorded from the LPI session: total laser energy, presence of bleeding, and post-laser intraocular pressure (IOP). Information gathered from the follow-up visits included visual acuity (VA), IOP, hyphema, and need to repeat LPI. A logistic regression analysis with modification for rare events was used to examine the relationship between the dependent variables and the group, adjusted for the clinical and demographic characteristics of patients.

MAIN OUTCOME MEASURES

The LPI procedure parameters (total energy), postoperative VA and IOP, risk for complications, and need for re-treatment were compared between groups using odds ratio (OR) measurements.

RESULTS

A total of 333 eyes were included in the study. The residents used statistically significant higher total energy compared with the glaucoma specialists' group (P < 0.001). After adjusting for demographic characteristics, antiplatelet/anticoagulant use, and laser energy parameters, we found that the patients of the residents group had a significantly increased likelihood for re-treatment within 3 months (OR, 3.38; 95% confidence interval [CI], 1.31-8.73) and anterior chamber bleeding (OR, 7.48; 95% CI, 1.07-52.02).

CONCLUSIONS

Although LPI is an effective and minimally invasive procedure, evidence shows that a higher level of experience leads to clinically and statistically significant better outcomes.