Effect of antiglaucoma agents on short-term intraocular pressure fluctuations after intravitreal bevacizumab injections

[Topical application of hypotensive drugs for the prevention of intraocular pressure elevation after intravitreal injections of anti-VEGF drugs]

The management protocol for patients with neovascular age-related macular degeneration (nAMD) involves multiple intravitreal injections (IVI) of anti-VEGF drugs. The ability to reduce the peak intraocular pressure (IOP) rise is greatly important in clinical practice.

PURPOSE

This study evaluates the effect of topical hypotensive drugs on the short-term IOP rise after IVI of anti-VEGF drugs in patients with nAMD.

MATERIAL AND METHODS

The prospective study included 80 patients with newly diagnosed nAMD. Before the start of treatment, the patients were divided into 4 groups of 20 people each: 1st - controls, who received no prophylactic drugs, in the 2nd, 3rd and 4th groups local instillations of one drop of hypotensive drugs brinzolamide 1%, brinzolamide-timolol, brimonidine-timolol were performed in the conjunctival sac twice: 1 day before the injection (at 20:00) and on the day of the injection 2 hours before the manipulation (at 08:00), respectively. IOP was measured in each patient using ICare Pro non-contact tonometer before injection, as well as 1 min, 30 and 60 min after injection.

RESULTS

Prophylactic use of hypotensive drugs was associated with a significant decrease in IOP immediately after IVI compared to the same parameter in the 1st group (p<0.001), the maximum decrease in IOP values was observed when using a fixed combination of brimonidine-timolol by 12.1 mm Hg compared to the controls (p<0.001), the combination of brinzolamide-timolol reduced IOP by 8.5 mm Hg (p<0.001), brinzolamide 1% led to the smallest decrease in IOP - by 5.1 mm Hg (p<0.001).

CONCLUSION

Study patients that received instillations of brimonidine-timolol combination of one drop into the conjunctival sac 1 day before the injection and on the day of the injection showed the maximum decrease in IOP compared to patients of the other groups.

Prophylactic intraocular pressure lowering measures in anti-vascular endothelial growth factor therapy: A systematic review and meta-analysis

Acute intraocular pressure (IOP) elevation following repeat intravitreal anti-vascular endothelial growth factor (VEGF) injections (IVI) may pose a risk to the integrity of the retinal nerve fiber (RNFL). This meta-analysis investigates the role of IOP-lowering interventions such as an anterior chamber paracentesis (ACP) and IOP-lowering medications on the IOP in patients undergoing IVIs. MEDLINE, EMBASE, and the Cochrane Library were searched up to February, 2021. Studies investigating IOP-lowering interventions in patients undergoing IVI versus controls were included. The primary outcome was the IOP in the short- and long-term post-IVI. Secondary outcomes were changes in the RNFL thickness and best corrected visual acuity (BCVA). ACP at time of anti-VEGF injection significantly lowered IOP immediately post anti-VEGF (WMD: -27.98 mm Hg, P < 0.001). Patients in the ACP group also had significantly thicker RNFL compared to control (WMD: 2.07 um, P < 0.00001) at median follow-up of 16.5 months. IOP-lowering medications (on the day of injection or in the long-term) significantly reduced IOP up to 30 minutes after injection (WMD: -3.31 mm Hg, P = 0.003). This effect was statistically significant between the 2 arms up to 1 month follow-up. There was no difference in BCVA in intervention versus controls. ACP reduces immediate IOP spikes post-IVI and preserves the RNFL in the short- and longterms IOP-lowering medications also reduce IOP spike, with limited data on RNFL thickness.

[Prevention of intraocular pressure elevation following intravitreal injections]

Determining the role of vascular endothelial growth factor (VEGF) in the pathogenesis of intraocular neovascularization prompted the development of anti-VEGF therapy. In general, these intravitreal injections (IVI) are considered relatively safe. One of the side effects that can occur after IVI of anti-VEGF agents is ocular hypertension, it can be acute or persistent. Numerous studies investigating the prevention of ophthalmic hypertension have been carried out in connection with the proven risk of short-term intraocular pressure (IOP) elevation after anti-VEGF injections. Scientific literature describes several methods of preventing intraocular pressure spikes after IVI: prophylactic medications, anterior chamber paracentesis, scleral decompression. Despite the significant number of publications, there is no universal consensus on the necessity of prevention measures for IVI of anti-VEGF drugs since the clinical benefits of slightly reducing the short-term IOP spikes remain unclear. This literature review analyzes the prospects of preventing ocular hypertension after IVI of anti-VEGF agents.

Prophylactic effect of brinzolamide-brimonidine fixed combination on intraocular pressure spikes after intravitreal anti-VEGF injections

PURPOSE

To evaluate the effect of topical prophylaxis with brinzolamide-brimonidine fixed combination on short-term intraocular pressure (IOP) elevation after intravitreal injections of anti-vascular endothelial growth factors (anti-VEGF).

METHODS

This prospective comparative study included 56 eyes of 47 patients treated with intravitreal injections of anti-VEGF, and they were randomly divided into two groups. In control group (25 eyes), no prophylactic medication was used, whereas in case group (31 eyes) one drop of a fixed combination of brinzolamide-brimonidine was instilled two hours before the injection. IOP was measured before the injection and at 1 min, 10 min and 30 min post-injection in all eyes.

RESULTS

The mean IOP before injection at 1 min, 10 min and 30 min post-injection was 16,6 ± 2,8 mmHg, 53,4 ± 12 mmHg, 26,4 ± 5,5 mmHg and 17,9 ± 4 mmHg, respectively, in control group and 15,1 ± 3,4 mmHg, 42,6 ± 8,4 mmHg, 21,4 ± 5,5 mmHg and 12,4 ± 3,5 mmHg, respectively, in case group. At 1 min, 10 min and 30 min post-injection, the mean IOP was significantly lower in case group compared with control group (p < 0,001, p = 0,0014 and p < 0,0001, respectively), but no difference at the pre-injection IOP between the two groups was found (p = 0,09).

CONCLUSIONS

The prophylactic administration of one drop of brinzolamide-brimonidine fixed combination significantly reduces the IOP spikes during the first 30 min after the intravitreal anti-VEGF injection.