Effects of Intravitreal Anti-VEGF Therapy on Glaucoma-like Progression in Susceptible Eyes

Retinal and choroidal changes after anti-VEGF therapy in neovascular-AMD patients: A systematic review and meta-analysis of SD-OCT studies

BACKGROUND

In recent years, the progress made in the field of optical coherence tomography has helped to understand the changes in eye layers in patients with exudative age-related macular degeneration (nAMD). Early diagnosis of nAMD, a leading cause of irreversible vision impairment, is helpful. Therefore, we performed a meta-analysis on OCT measurement alterations before and after anti-VEGF therapy in patients with nAMD and controls.

METHOD

We systematically searched Scopus, PubMed, Cochrane, and Web of Science to find articles that measured choroidal and retinal layer changes after anti-VEGF therapy in nAMD Patients. We chose either a fixed-effects or random-effects model based on the assessed heterogeneity level to perform a meta-analysis. In addition, we conducted meta-regression, subgroup analyses, publication bias, and quality assessment for included studies.

RESULTS

Thirteen studies were included in the meta-analysis, with 733 total participants. Foveal thickness and subfoveal choroidal thickness (CT) decreased significantly in the first 3 years after injections, except for subfoveal CT in the third year after injection. It also showed that CT at 1500 µm temporal and nasal to the fovea did not significantly change.

CONCLUSION

Our results showed anti-VEGF treatment for nAMD patients was associated with a significant reduction in foveal thickness and subfoveal CT in the first 2 years after treatment. Our analysis did not reveal any correlation between changes in foveal thickness and subfoveal CT with best-corrected visual acuity or other factors.

Effect of Repeated Intravitreal Injections in Glaucoma Spectrum Diseases

Purpose

To evaluate whether repeated intravitreal injections (IVI) with an anti-vascular endothelial growth factor (anti-VEGF) agent are associated with glaucomatous progression in eyes with glaucoma spectrum diseases (GSD).

Methods

Single-center, retrospective, longitudinal study of patients with bilateral and similar GSD who: (1) received ≥8 IVI in only one eye during the study period; (2) had ≥2 retinal nerve fiber layer thickness (RNFL) measurements obtained by spectral-domain optical coherence tomography (SD-OCT) at least 12 months apart. The primary outcome was the absolute RNFL thickness change, comparing injected and fellow uninjected eyes. Linear mixed effects models were constructed, including a multivariable model.

Results

Sixty-eight eyes from 34 patients were included, 34 injected and 34 fellow uninjected eyes. Average baseline age was 67.68±21.77 years with a follow-up of 3.66±1.89 years and 25.12±14.49 IVI. RNFL thickness decreased significantly from 80.92±15.78 to 77.20±17.35 μm (p<0.001; -1.18±1.93 μm/year) in injected eyes and from 79.95±17.91 to 76.61±17.97 μm (p<0.001; -1.07±0.98 μm/year) in uninjected eyes. In a multivariable linear mixed model of injected eyes, only higher baseline RNFL thickness (p < 0.001) significantly predicted higher absolute RNFL thickness loss. Neither absolute RNFL thickness variation (p=0.716) nor RNFL rate (p=0.779) was significantly different between paired injected and uninjected eyes. Absolute IOP variation was not significantly different between groups (16.62±4.77 to 15.09±4.34 mmHg in injected eyes and 17.68±5.01 to 14.50±3.39 mmHg in fellow uninjected eyes; p=0.248). The proportion of eyes receiving glaucoma medical treatment increased significantly in both groups (55.9% to 76.5% in injected eyes; p=0.039; 58.8% to 76.5% in uninjected eyes; p = 0.031). The number of glaucoma medications also increased significantly in both groups (1.03±1.11 to 1.59±1.18 glaucoma medications in injected eyes; p=0.003; 1.09±1.11 to 1.56±1.19 glaucoma medications in uninjected eyes; p=0.003).

Conclusion

Repeated IVI do not seem to accelerate glaucomatous progression. Future studies with a longer follow-up are needed.

Glaucoma progression in patients receiving intravitreal anti‐VEGF treatment for neovascular age‐related macular degeneration

PURPOSE

The purpose of this study was to investigate how often glaucoma and neovascular age-related macular degeneration (nAMD) occur in the same patient and to evaluate whether glaucoma progression is faster in eyes treated with intravitreal anti-VEGF medications for nAMD.

METHODS

This single-centre retrospective real-world data (RWD) consists of medical records of 6314 glaucoma and 2166 nAMD patients treated in 2008-2017 in Tays Eye Centre, Finland. To study glaucoma progression, changes in visual fields (mean deviation [MD], dB/year), IOP (mmHg/year) and fundus photographs (progression, yes/no) were compared in glaucoma eyes with and without anti-VEGF treatment for nAMD and ≥1 year follow-up.

RESULTS

During the 10-year period, 147 patients with glaucoma received intravitreal anti-VEGF treatment for nAMD corresponding to 2% of glaucoma and 7% of nAMD patients. The mean change in MD was -0.70 dB/year (SD 1.8) vs. -0.27 dB/year (SD 1.7) (p = 0.027) in glaucoma eyes with (n = 37) and without (n = 4304) anti-VEGF injections, respectively. In patients with bilateral glaucoma and unilateral nAMD treated with anti-VEGF injections (n = 20), MD declined at -0.62 dB/year (SD 1.9) vs 0.33 dB/year (SD 1.5) (p = 0.654), and glaucoma progression was detected in 14/20 vs 10/20 (p = 0.219) fundus photographs in eyes with anti-VEGF treatment compared with their untreated fellow eyes.

CONCLUSION

nAMD and glaucoma were found co-existing in the same eye at rates that were similar to the age-corrected prevalence of the two diseases in the general population. Our results suggest that intravitreal anti-VEGF treatment for nAMD may accelerate glaucoma progression.

Risk, Prevalence, and Progression of Glaucoma in Eyes With Age-Related Macular Degeneration Treated With Intravitreal Anti-Vascular Endothelial Growth Factor Injections

PURPOSE

To examine the risk, prevalence, and progression of glaucoma development in age-related macular degeneration (AMD) eyes receiving intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections compared to controls.

DESIGN

Retrospective clinical cohort study.

METHODS

Retrospective review of eyes receiving intravitreal anti-VEGF injections from January 1, 2004, to December 31, 2013, for exudative AMD. Age- and sex-matched control groups of eyes included eyes with nonexudative AMD (NEAMD) and no AMD. Eyes with a diagnosis of glaucoma or glaucoma suspect were reviewed for injection details, type and date of glaucoma diagnosis, glaucoma treatments, standard automated perimetry (SAP), and spectral domain optical coherence tomography (SD-OCT). Qualitative progression was determined by indication of glaucoma progression in provider notes. Quantitative progression was assessed based on change in mean deviation (MD) on SAP, retinal nerve fiber layer thickness on SD-OCT, and intraocular pressure (IOP).

RESULTS

There were 707 eyes of 504 patients treated with anti-VEGF injections and 1008 eyes in the NEAMD and no-AMD cohorts. There was no difference in glaucoma or suspect prevalence at initial presentation between eyes treated with injections and NEAMD (6.9% vs 9.7%, P = .22) or no-AMD controls (vs 8.5%, P = .55). There was no difference in cumulative 5-year probability of new glaucoma diagnosis after anti-VEGF injections compared to NEAMD (1.9% vs 1.0%, P = .69) or no-AMD controls (vs 1.6%, P = .88). There was no difference in qualitative progression of glaucoma in the injection cohort vs NEAMD (P = .19) or no-AMD controls (P = .61). The rate of MD change in injection eyes was similar to NEAMD eyes (P = .74) but greater than no-AMD eyes (P = .02). Eyes receiving injections required more topical glaucoma medications compared with NEAMD (P = .03) and more glaucoma laser treatments compared with no-AMD controls (P = .009). Eyes receiving injections did not require more frequent incisional glaucoma surgery compared with NEAMD (21.0% vs 15.0%, P = .95) or no-AMD controls (vs 10.0%, P = .10).

CONCLUSION

Eyes treated with intravitreal anti-VEGF injections for exudative AMD did not have increased risk of developing glaucoma compared with controls. Of those with a glaucoma diagnosis, exudative AMD eyes receiving injections required a greater number of topical glaucoma medications compared with NEAMD eyes and had a greater rate of MD loss than no-AMD controls.

Systemic and Ocular Adverse Events with Intravitreal Anti-VEGF Therapy Used in the Treatment of Diabetic Retinopathy: a Review

PURPOSE OF REVIEW

Intravitreal anti-vascular endothelial growth factor (VEGF) agents are used routinely in the management of neovascular conditions including proliferative diabetic retinopathy and diabetic macular edema. While the efficacy of anti-VEGF agents has been well-validated, their ocular and systemic adverse events should always be considered and discussed with patients. The aim of this review is to discuss the most recent literature reports regarding the various ocular and systemic adverse events associated with intravitreal anti-VEGF treatment in diabetic retinopathy.

RECENT FINDINGS

The most frequently reported adverse ocular events include subconjunctival hemorrhage, vitreous hemorrhage, increased intraocular pressure, uveitis, endophthalmitis, ocular surface disease, and traumatic cataract. Subconjunctival hemorrhage and vitreous hemorrhage are the most common ocular adverse events reported with intravitreal anti-VEGF treatment. The most serious (though rare) ocular adverse events include endophthalmitis and rhegmatogenous retinal detachment. A consensus regarding the association of systemic adverse events (such as myocardial infarction, stroke, and death) with intravitreal anti-VEGF treatments has not been established. Intravitreal anti-VEGF therapy is used in the treatment of diabetic retinopathy, macular degeneration, and other diseases. These agents are associated with a variety of ocular and systemic adverse events that ophthalmologists should always consider.

Intra-Ocular Pressure Response to Dexamethasone Implant Injections in Patients with a History of Filtering Surgery: The TRABEX Study

Patients with both macular edemas, of various etiologies such as diabetes and glaucoma, may suffer serious loss of vision if either disease goes untreated. Where no effective alternative therapies are available, dexamethasone implant (DEX-I) injections may be the only choice of treatment, despite the risk of a possible increase in intraocular pressure (IOP) when using steroids. Although many studies have reported on IOP evolution in eyes treated with DEX-I, little is known specifically about eyes with a history of filtering surgery. The aim of this observational series was to evaluate the IOP response following DEX-I injection in eyes presenting conventional filtering surgeries or microinvasive glaucoma surgeries (MIGS). Twenty-five eyes were included in this study. A total of 64% of the eyes did not experience OHT during follow-up. Additional IOP-lowering therapy was needed for 32% of eyes, and 20% of eyes (all showing bleb fibrosis) required further filtering surgery: 50% of eyes in the MIGS group and 10.5% of eyes in the conventional filtering surgery group. A significant positive correlation was found between IOP at baseline and the maximum IOP throughout follow-ups after DEX-I (r = 0.45, p = 0.02). In conclusion, if DEX-I is used when there are no alternative therapies for treating macular edema, IOP in eyes with a history of filtering surgery is generally manageable. Those eyes which previously underwent conventional therapy with effective blebs obtained better IOP control after DEX-I injections and mostly did not require any additional IOP-lowering therapy or surgery.

Efficacy of an Anti-Semaphorin 3A Neutralizing Antibody in a Male Experimental Retinal Vein Occlusion Mouse Model

Purpose

Semaphorin 3A (Sema3A) is a promising therapeutic target for macular edema in age-related macular degeneration, diabetic retinopathy, and retinal vein occlusion (RVO). Anti-vascular endothelial growth factors (anti-VEGFs) are the current standard of care for many retinal diseases. This study investigated the Sema3A neutralizing antibody BI-X and/or anti-VEGF therapy (aflibercept) in an RVO mouse model. Treatment efficacy was examined and grouped by timing subsequent to the RVO mouse model induction: efficacy against the onset of intraretinal edema 1 day postinduction and protective effects at 7 days postinduction.

Methods

We examined the changes in expression of Sema3A in the retina of an RVO mouse model. In addition, changes in expression of tumor necrosis factor (TNF)-α and semaphorin-related proteins (neuropilin-1 and plexin A1) in the retina upon treatment were analyzed by Western blotting. The effects of BI-X and/or aflibercept were evaluated using measures of retinal edema, blood flow, and thinning of the inner nuclear layer.

Results

Induction of vein occlusion in the RVO mouse model significantly increased Sema3A expression in the retina, particularly in the inner nuclear layer. BI-X was effective as a monotherapy and in combination with anti-VEGF therapy, demonstrating a beneficial effect on intraretinal edema and retinal blood flow. Moreover, in the RVO mouse model, BI-X monotherapy normalized the changes in expression of TNF-α and semaphorin-related proteins.

Conclusions

These findings support targeting Sema3A to treat intraretinal edema and retinal ischemia.

Comparison of risks of arterial thromboembolic events and glaucoma with ranibizumab and aflibercept intravitreous injection: A nationwide population‐based cohort study

Background

To compare intravitreal aflibercept injection with intravitreal ranibizumab injection for the risk of major arterial thromboembolic events (ATEs) and glaucoma.

Methods

This retrospective, nationwide cohort study investigated 15 611 and 3867 patients aged >50 years with at least one pharmacy claim for intravitreal ranibizumab injection and aflibercept injection between 2011 and 2016, respectively. The inverse probability of treatment weighting method was performed to adjust the baseline difference between the two groups and the hazard risk of adverse events was estimated using the Cox proportional regression model.

Results

No significant difference was noted between intravitreal ranibizumab and aflibercept injection for arterial thromboembolic risk, including ischemic stroke and acute myocardial infarction, during a 2-year follow-up (adjusted hazard ratio (HR): 0.87, 95% confidence interval (CI): 0.53–1.42; P = .583). Subgroup analyses revealed that patients age >65 years (adjusted HR: 0.64, 95% CI: 0.45–0.92) and those without coronary artery disease (adjusted HR: 0.59, 95% CI: 0.37–0.95) had significantly lower arterial thromboembolic risk in the aflibercept group than in the ranibizumab group. Additionally, the risk of glaucoma development after intravitreal injection did not significantly differ between the two groups (adjusted HR: 0.63, 95% CI: 0.37–1.06; P = .084).

Conclusions

No significant differences in the risk of major ATEs and glaucoma were found between ranibizumab and aflibercept, and aflibercept might be safe for use in elderly patients.

Effects of Postoperative Intravitreal Injections on Outcomes of Traditional Glaucoma Surgery in Patients with Preoperative Intravitreal Injections

PURPOSE

To compare outcomes of glaucoma drainage device (GDD) implantation and trabeculectomies with and without postoperative intravitreal injections (IVIs) in glaucoma patients with a history of preoperative IVIs.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A total of 133 eyes of 133 glaucoma patients who underwent GDD implantation or trabeculectomy with at least 1 IVI preoperatively between January 2005 and October 2020 at Massachusetts Eye and Ear.

METHODS

Chart review of glaucoma patients with traditional glaucoma surgery and at least 1 IVI before surgery. All statistical analyses were conducted with R statistical programming software.

MAIN OUTCOME MEASURES

Intraocular pressure (IOP), medication burden, best-corrected visual acuity (BCVA), Kaplan-Meier success rates, adjusted hazard ratios (HRs), and complications.

RESULTS

Baseline demographics were similar between the groups with and without postoperative IVIs. The group with postoperative IVIs had a higher proportion of diabetic retinopathy and retinal vascular occlusions than the group without postoperative IVIs, which had more eyes with age-related macular degeneration. Intraocular pressure, medication burden, and visual acuity were similar between groups at all time points except for IOP at 6 weeks, which was lower in the group with postoperative IVIs. The group with postoperative IVIs had significantly more preoperative IVIs than the group without postoperative IVIs (6.6 vs. 3.3, P = 0.017). For success defined as IOP reduction ≥ 20% with 5 < IOP ≤ 21 mmHg, Kaplan-Meier analyses demonstrated similar success rates between groups with and without IVIs. When stratified by the number of IVIs, success rates for the group with 7 or more IVIs were significantly higher than the success rates for the group with 0-6 IVIs (P = 0.005). Each additional postoperative IVI resulted in a 7.2% decrease in the hazard of failure to achieve our stated success criteria. With regard to late complications, the group with postoperative IVIs had a higher incidence of vitreous hemorrhage (18.5% vs. 3.2%, P = 0.039) than the group without postoperative IVIs.

CONCLUSIONS

A higher number of postoperative IVIs, specifically 7 or more IVIs, may be associated with improved success rates of traditional glaucoma surgery in glaucoma patients who received IVIs before surgery.

Rates of RNFL Thinning in Patients with Suspected or Confirmed Glaucoma Receiving Unilateral Intravitreal Injections for Exudative AMD

PURPOSE

This study evaluated whether the rate of retinal nerve fiber layer (RNFL) thinning is faster in eyes receiving intravitreal injections than in fellow uninjected eyes among patients suspected of having or confirmed to have glaucoma and exudative age-related macular degeneration (AMD).

DESIGN

Retrospective comparative cohort study.

METHODS

Patients with a diagnosis of unilateral exudative AMD and confirmed to have or suspected of having glaucoma in both eyes receiving unilateral intravitreal injections were identified. Those with ≥3 RNFL optical coherence tomography scans and ≥6 injections were included in the study. Rates of RNFL thinning in the injected eye versus the uninjected eye were estimated using linear mixed models. The main outcome measurement was the differences in rates of RNFL thinning in the injected versus the fellow uninjected eye. The effects of postinjection elevation of intraocular pressure (IOP), injection frequency, and number of injections were also evaluated.

RESULTS

A total of 53 patients met the inclusion criteria, receiving 26.4 ± 15.9 intravitreal injections. The average rate of RNFL thinning in uninjected eyes was -0.620 μm/year (P = .029). Injected eyes had an additional incremental loss of -0.385 μm/year, but this value was not statistically significant (95% confidence interval [CI]: -1.147 to 0.379 μm/year; P = .324). Subgroup analysis with only glaucoma patients (n = 33) also demonstrated a nonsignificant effect of injections (-0.568 μm/year; 95% CI: -1.454 to 0.319 μm/year; P = .212). Postinjection IOP elevation, injection frequency, and total number of injections were not associated with faster RNFL loss.

CONCLUSIONS

Among exudative AMD patients with glaucoma or suspected of having glaucoma, the rate of RNFL thinning in eyes receiving intravitreal injections did not significantly differ from that of fellow uninjected eyes.

Current intravitreal therapy and ocular hypertension: A review

To determine the effect of commonly used intravitreal agents on immediate and long-term IOP elevations and their association, if any, with glaucoma. Literature searches in PubMed and the Cochrane databased in January 2020 yielded 407 individual articles. Of these, 87 were selected for review based on our inclusion criteria. Based on the evidence provided, 20 were assigned level I, 27 level II, and 22 level III. Eight articles were rejected because of poor quality, insufficient clarity, or irrelevance based on standardized protocols set out by the American Academy of Ophthalmology. The studies that reported on short-term IOP elevation (i.e., between 0 and 60 min) showed that an immediate increase in IOP is seen in all patients who receive anti-VEGF agents or triamcinolone acetonide when measured between 0 and 30 min of intravitreal injection and that the IOP elevation decreases over time. The data on long-term IOP elevation were mixed; Pretreatment with glaucoma medications, anterior chamber tap, vitreous reflux, longer intervals between injections, and longer axial lengths were associated with lower IOP elevations after injection of anti-VEGF agents, while the position of the implant vis-à-vis, the anterior chamber was important for steroid therapy. Data were mixed on the relationship between IOP increase and the type of intravitreal injection, number of intravitreal injections, preexisting glaucoma, and globe decompression before injection. There were no data on the onset or progression of glaucoma in the studies reviewed in this assessment. However, some studies demonstrated RNFL thinning in patients receiving chronic anti-VEGF therapy. Most, if not all, intravitreal agents cause ocular hypertension, both in the short term and long term. The functional consequences of these observations are not very clear.

[Anti-angiogenesis therapy of diabetic macular edema in patients with primary open-angle glaucoma]

Despite the high clinical effectiveness and widespread introduction of anti-angiogenesis (anti-VEGF) therapy into practice, its long-term effect on the development of structural changes in the treatment of primary open-angle glaucoma (POAG) patients with diabetic macular edema (DME) hasn't been studied sufficiently and so presents certain interest.

PURPOSE

To study the effect of anti-VEGF therapy on the structural and functional state of the retina and optic nerve in patients with DME and POAG.

MATERIAL AND METHODS

The study included 72 patients (132 eyes): the 1^st group - 22 patients (40 eyes) with stage I POAG and DME, the 2^nd group - 25 patients (46 eyes) with DME receiving anti-VEGF therapy. The 3^rd group (control) consisted of 25 patients (46 eyes) with stage I POAG. The observation period lasted 24 months. The average number of injections was 8.48±3.65. The indicators for evaluation were: visual acuity, tonometry, perimetry, optical coherence tomography (OCT) of the optic nerve and macular region.

RESULTS

By the end of the observation period, the increase in IOP in the groups was +0.82 (4.4%), 0.41 (2.4%), 0.65 (3.6%) mm Hg. In the group of comorbid patients, a small-scale increase trend of BCVA was noted: +0.05 (6.6%), a decrease in MD by -2.48 Db (92.1%), an increase in excavation volume by 0.16 (43.2%) mm³, decrease in the area of RA by 0.3 mm² (12.7%). A decrease in retinal nerve fibers layer (RNFL) thickness of 6.55 μm (7.8%), mainly the superior (9.2%), inferior (7.3%) and nasal sectors (7.9%). Loss of GCL+IPL 8.68 μm (12.7%) in the superior (19%), superonasal (20.2%) and inferonasal (20.7%) sectors.

CONCLUSION

The combined course of POAG and DME is accompanied by a decrease in the functional and structural parameters of the retina and optic nerve, and a higher rate of progression of glaucomatous optic neuropathy. Long-term results did not reveal a significant deterioration in the structural parameters of the optic disc and retina against the background of anti-VEGF therapy when comparing the study groups.

Initial Ten Years of Experience with the Intravitreal Dexamethasone Implant: A Retrospective Chart Review

Purpose

To evaluate the initial ten years of results from the intravitreal dexamethasone implant (DEX) in patients treated for retinal vein occlusion (RVO), diabetic macular edema (DME) or uveitis.

Methods

Retrospective chart review of patients receiving DEX since its FDA approval. Best-corrected visual acuity (BCVA), central macular thickness (CMT) on optical coherence tomography, intraocular pressure and cataract status were collected. Baseline data were collected from the initial DEX and post-treatment data at the visit at least four weeks after the last DEX.

Results

In total, 315 eyes received 1216 DEX over 63.9±4.6 weeks. In the branch RVO (n=90), central RVO (n=59) and DME (n=62) cohorts, BCVA improved significantly (p<0.05). The uveitis (n=154) cohort did not have a significant change in BCVA, 0.62±0.04 to 0.61±0.04 logMAR (p=0.34). Younger patients, vitrectomized eyes, and eyes without a history of glaucoma were associated with significantly better BCVA outcomes in the uveitis cohort (p<0.05). Overall, CMT decreased significantly from 376.6±6.8 to 322.7±5.0 µm (p<0.05). Intraocular pressure increased significantly (p<0.001) and the percentage of patients requiring anti-glaucoma medications increased from 33.0% to 67.6%. Of phakic eyes, 58.8% (n=63) had cataract progression or underwent surgery with those who underwent surgery experiencing a significant improvement in BCVA (p<0.05).

Conclusion

Repeated DEX over extended follow-up offers significant anatomic benefits to all cohorts. Visual benefits are only seen in RVO, DME and select uveitis demographics.

Effect of Intravitreal Injections on Retinal Imaging Metrics in Glaucomatous and Non-Glaucomatous Eyes

Purpose of Review

To summarize the available literature on retinal imaging metrics in the context of intravitreal injections in glaucomatous and non-glaucomatous eyes.

Recent Findings

The retinal nerve fiber layer (RNFL) in injected non-glaucomatous eyes appears to thin at a similar rate to uninjected fellow eyes. A total of four studies evaluating RNFL thinning in injected glaucomatous eyes yielded mixed results, with more recent longitudinal investigations suggesting a potential association. The ganglion cell-inner plexiform layer is also being studied as a potential endpoint in both glaucomatous and non-glaucomatous eyes following intravitreal injections.

Correlation of ocular rigidity with intraocular pressure spike after intravitreal injection of bevacizumab in exudative retinal disease

BACKGROUND/AIMS

To evaluate the non-invasive measurement of ocular rigidity (OR), an important biomechanical property of the eye, as a predictor of intraocular pressure (IOP) elevation after anti-vascular endothelial growth factor (anti-VEGF) intravitreal injection (IVI).

METHODS

Subjects requiring IVI of anti-VEGF for a pre-existing retinal condition were enrolled in this prospective cross-sectional study. OR was assessed in 18 eyes of 18 participants by measurement of pulsatile choroidal volume change using video-rate optical coherence tomography, and pulsatile IOP change using dynamic contour tonometry. IOP was measured using Tono-Pen XL before and immediately following the injection and was correlated with OR.

RESULTS

The average increase in IOP following IVI was 19±9 mm Hg, with a range of 7-33 mm Hg. The Spearman correlation coefficient between OR and IOP elevation following IVI was 0.796 (p<0.001), showing higher IOP elevation in more rigid eyes. A regression line was also calculated to predict the IOP spike based on the OR coefficient, such that IOP spike=664.17 mm Hg·µL×OR + 4.59 mm Hg.

CONCLUSION

This study shows a strong positive correlation between OR and acute IOP elevation following IVI. These findings indicate that the non-invasive measurement of OR could be an effective tool in identifying patients at risk of IOP spikes following IVI.