The intravitreal administration of treatments for diabetic macular edema can, in susceptible patients, increase intraocular pressure (IOP). |
Increased IOP can threaten sight if not detected and treated promptly. |
It is not possible to determine before treatment which patients will experience an IOP rise but those with a relatively high baseline IOP, a previous IOP rise, or a history of glaucoma may be more susceptible. |
IOP should be monitored in all patients throughout the lifespan of their intravitreal treatment, with closer monitoring in those most at risk. |
Algorithms are proposed that tailor the frequency and extent of monitoring depending on individual susceptibility and current IOP, with the aim of ensuring that any potentially problematic IOP rise is detected and treated promptly while allowing a lower level of monitoring in patients with a low risk. |
Introduction
-
Closer monitoring in patients who are most susceptible to developing an IOP rise (i.e., those with a baseline IOP of ≥ 22 mmHg or a prior history of an IOP event)
-
Closer monitoring in patients whose IOP increases ≥ 10 mmHg from baseline
-
Greater clarity on the timing of monitoring visits
-
Greater flexibility for retina specialists regarding when to initiate IOP-lowering medication and when to refer to a glaucoma specialist (which helps overcome logistical difficulties where local facilities are lacking)
-
Greater clarity on the stepwise introduction of treatments when IOP exceeds 25 mmHg and a de-emphasizing of the potential usefulness of selective laser trabeculoplasty as monotherapy in this scenario
-
The incorporation of a dynamic feedback mechanism which means the guidance continually adapts in line with the latest IOP measurement (to ensure it accurately reflects the current risk level throughout what could be a lengthy period of monitoring).
Overview of Recent Key Data
Key findings from evaluations of one or more intravitreal corticosteroid implants | Conclusion |
---|---|
•The incidence of patients with diabetic macular edema (DME) whose intraocular pressure (IOP) increased by ≥ 10 mmHg—or whose IOP was ≥ 25 mmHg, ≥ 30 mmHg, or ≥ 35 mmHg—was greater after injection of an intravitreal dexamethasone implant than after a sham injection procedure (a needleless applicator pressed against the conjunctiva) [27] | Implantation of an intravitreal corticosteroid may increase the likelihood of a clinically significant rise in IOP or ocular hypertension |
•The incidence of eyes with DME having an IOP > 25 mmHg was significantly greater after injection of an intravitreal fluocinolone acetonide implant than before implantation [39] | Implantation of an intravitreal corticosteroid may increase the likelihood of ocular hypertension |
•During the various follow-up periods after injection of an intravitreal corticosteroid implant, IOP was: | A proportion of eyes may develop clinically significant IOP after implantation of an intravitreal corticosteroid |
•Relative to eyes without a history of prior IOP events, eyes with a history of prior IOP events that received an intravitreal fluocinolone acetonide implant for DME had a significantly higher incidence of [19]: IOP rising by ≥ 10 mmHg (45.7% vs 19.1%; p < 0.001) IOP > 25 mmHg (56.4% vs 20.4%; p < 0.001) IOP > 30 mmHg (35.1% vs 8.0%; p < 0.001) Needing IOP-lowering medication (50.0% vs 17.9%; p < 0.001) | A history of a prior IOP event significantly (p < 0.001) increases the likelihood of an intravitreal corticosteroid implant resulting in: IOP rising by ≥ 10 mmHg IOP exceeding 25 mmHg or 30 mmHg IOP-lowering medication being needed |
•The incidence of patients or eyes with DME reported to receive IOP-lowering treatments after injection of an intravitreal corticosteroid implant was: Up to 46% for medicationa 0–1.3% for trabeculoplastya 0–1.2% for trabeculectomy 0–3.7% for IOP-lowering surgerya | The vast majority of eyes requiring IOP-lowering therapy after intravitreal corticosteroid implantation are managed with glaucoma medication. Only a small minority of eyes are treated with laser or surgery |
Pre-implantation Considerations
-
Baseline IOP of ≥ 22 mmHg (ocular hypertension according to the European Glaucoma Society [43]).
-
History of an IOP rise to > 25 mmHg or an IOP rise of ≥ 10 mmHg.
-
Prior or current need for IOP-lowering treatment.
Post-Implantation Recommendations
Hypothetical Patient Scenarios Illustrating the Guidelines in Action
JOHN | ||
History | No prior history of intravitreal corticosteroid treatment or raised IOP or glaucoma | |
Baseline IOP | 14 mmHg | |
Pre-implantation assessment | John does not have any of the above-mentioned factors that might make him more susceptible to an IOP rise and so his retina specialist can consider him for an intravitreal corticosteroid implant without needing to consult glaucoma colleagues | |
Post-implantation monitoring | John is treated with the intravitreal corticosteroid implant. As he does not have any of the key factors increasing his susceptibility to an IOP rise, his monitoring follows the algorithm for less susceptible patients (Fig. 1). His IOP monitoring starts on the standard schedule (i.e., 2–7 days, 1 month, and 2–3 months after implantation and, thereafter, depending on the relevant risk classification) as follows: | |
7 days post-implantation: | IOP is 19 mmHg, so he is in the low-risk group | |
1 month post-implantation: | IOP is 24 mmHg and, because this is ≥ 10 mmHg higher than his baseline IOP, he moves to the high-risk group. His visual field is recorded, imaging is performed, and he is treated with one topical IOP-lowering medication within 1–2 weeks. He is followed up again 1–2 weeks after starting the medication | |
1.5 months post-implantation: | IOP is 26 mmHg, so a second topical IOP-lowering medication is added to his treatment | |
2 months post-implantation: | IOP is still 26 mmHg, so he is referred to a glaucoma specialist |
WILLIAM | ||
History | No prior history of intravitreal corticosteroid treatment or raised IOP or glaucoma | |
Baseline IOP | 21 mmHg | |
Pre-implantation assessment | William does not have any of the above-mentioned factors that might make him more susceptible to an IOP rise and so his retina specialist can consider him for an intravitreal corticosteroid implant without needing to consult glaucoma colleagues | |
Post-implantation monitoring | William is treated with an intravitreal fluocinolone acetonide implant. As he does not have any of the key factors that could increase his susceptibility to an IOP rise, his monitoring follows the algorithm for less susceptible patients (Fig. 1). His IOP monitoring starts on the standard schedule (i.e., 2–7 days, 1 month, and 2–3 months after implantation and, thereafter, depending on the relevant risk classification) as follows: | |
5 days post-implantation: | IOP remains at 21 mmHg, so he remains in the low-risk group | |
1 month post-implantation: | IOP is 22 mmHg, so he moves to the medium-risk group and has his visual field recorded and imaging performed for the first time | |
2 months post-implantation: | IOP returns to baseline level of 21 mmHg, so he returns to the low-risk group and his next IOP check will be in 3 months | |
5 months post-implantation: | IOP is 21 mmHg, so he remains in the low-risk group and continues with IOP checks quarterly | |
8 months post-implantation: | IOP is 20 mmHg | |
11 months post-implantation: | IOP is 28 mmHg, so he moves to the high-risk group, is treated within 2 weeks with a single topical IOP-lowering drug and, as he has not had his visual field recorded and imaging performed within the last 3 months, these are repeated. His next IOP check is scheduled for 2 weeks after starting the medication | |
12 months post-implantation: | IOP is 22 mmHg, so he moves to the medium-risk group and continues the medication. His retina specialist decides to schedule the next IOP check for 4 weeks later | |
13 months post-implantation: | IOP is 21 mmHg, so has returned to the baseline level. He returns to the low-risk group and continues the medication. His IOP continues to be monitored every 3 months for the 36-month lifespan of the fluocinolone acetonide implant | |
16 months post-implantation: | IOP is 21 mmHg | |
19 months post-implantation: | IOP is 21 mmHg. In this low-risk scenario, a washout of the topical medication can be considered to determine whether or not the medication needs to be continued | |
22 months post-implantation: | IOP is 21 mmHg | |
25 months post-implantation: | IOP is 21 mmHg | |
28 months post-implantation: | IOP is 20 mmHg | |
31 months post-implantation: | IOP is 20 mmHg | |
34 months post-implantation: | IOP is 21 mmHg |
ANN | ||
History | Ann hates injections but is very motivated to do everything possible to protect her eyesight. She once had an IOP of 28 mmHg a few weeks after a previous intravitreal dexamethasone implant but this was controlled with a single glaucoma medication | |
Baseline IOP | 20 mmHg | |
Pre-implantation assessment | Because of her prior history of an IOP rise beyond 25 mmHg after intravitreal corticosteroid treatment, Ann is more susceptible than most patients to developing another rise in IOP. As a result, her retina specialist should discuss protocols with the local glaucoma team to help determine Ann’s potential suitability for an intravitreal corticosteroid implant. The glaucoma team can also advise on monitoring and a plan of action if she has another rise in IOP | |
Post-implantation monitoring | Ann receives a fluocinolone acetonide implant because she can only tolerate the thought of a single injection every 3 years and not more frequently. Because of her prior history of an IOP event, her monitoring starts by following the algorithm for more susceptible patients (Fig. 2). Her visual field is recorded and imaging is performed. Her IOP monitoring starts on the standard schedule (i.e., 2–7 days, 1 month, and 2–3 months after implantation and, thereafter, depending on the relevant risk classification) as follows: | |
5 days post-implantation: | IOP is 20 mmHg, so she is in the medium-risk group | |
1 month post-implantation: | IOP is 21 mmHg, so she stays in the medium-risk group | |
3 months post-implantation: | IOP is 27 mmHg, so she moves to the high-risk group and within 1–2 weeks is treated with a single IOP-lowering medication. Her visual field and imaging are repeated and her IOP is scheduled for review within 1–2 weeks of starting treatment | |
3.5 months post-implantation: | IOP is 25 mmHg, so she moves back to the medium-risk group. Her retina specialist schedules her next IOP check for 4 weeks later | |
4.5 months post-implantation: | IOP remains at 25 mmHg and her retina specialist adds a second topical IOP-lowering medication to reduce IOP further and schedules another IOP check for 6 weeks later | |
6 months post-implantation: | IOP is 25 mmHg. Ann continues with the medication and stays in the medium-risk group. Her retina specialist decides to continue monitoring IOP every 2 months. Because IOP has not increased over the last two visits, visual field and imaging only need to be repeated within 6 months of the last check (which was at 3 months post-implantation), so these are scheduled for the next visit | |
8 months post-implantation: | IOP is 22 mmHg, visual field and imaging are repeated | |
10 months post-implantation: | IOP is 22 mmHg | |
12 months post-implantation | IOP is 21 mmHg | |
14 months post-implantation: | IOP is 21 mmHg, visual field and imaging are repeated | |
16 months post-implantation: | IOP is 21 mmHg | |
18 months post-implantation: | IOP is 21 mmHg | |
20 months post-implantation: | IOP is 21 mmHg, visual field and imaging are repeated. Her retina specialist has concerns over a possible change in the retinal nerve fibre layer so refers Ann to a glaucoma specialist |
ELSIE | ||
History | Elsie has no prior exposure to intravitreal corticosteroids but has been on IOP-lowering medication for several months | |
Baseline IOP | 19 mmHg | |
Pre-implantation assessment | Because of her existing need for IOP-lowering medication, Elsie is more susceptible than most patients to experiencing a corticosteroid-induced rise in IOP. Her retina specialist should discuss protocols with the local glaucoma team to help determine the potential suitability of an intravitreal corticosteroid implant. The glaucoma team can also advise on monitoring and a plan of action should a further rise in IOP occur | |
Post-implantation monitoring | Elsie receives an intravitreal corticosteroid implant and, because she is already on IOP-lowering treatment, her monitoring starts by following the algorithm for more susceptible patients (Fig. 2). Her visual field is recorded and imaging is performed. Her IOP monitoring starts on the standard schedule (i.e., 2–7 days, 1 month, and 2–3 months after implantation and, thereafter, depending on the relevant risk classification) as follows: | |
7 days post-implantation: | IOP is 19 mmHg, so she is in the medium-risk group | |
1 month post-implantation: | IOP is 21 mmHg, so she remains in the medium-risk group. As her IOP values over the last 2 visits have been unstable (i.e., have increased), her visual field and imaging are flagged to be repeated every 3 months and the results are to be shared with a glaucoma specialist | |
3 months post-implantation: | IOP is 22 mmHg and, as indicated previously, visual field and imaging results are repeated and the results shared with a glaucoma specialist for advice on ongoing management |