Perioperative medications for preventing temporarily increased intraocular pressure after laser trabeculoplasty

Outcomes of Micropulse Laser Trabeculoplasty Compared to Selective Laser Trabeculoplasty: A Systematic Review and Meta-Analysis

Purpose

To perform a meta-analysis and systematic review to compare the efficacy and complications of micropulse laser trabeculoplasty (MLT) and selective laser trabeculoplasty (SLT) in adult patients with open-angle glaucoma (OAG) and ocular hypertension (OHT).

Methods

We performed a systematic review utilizing PubMed, Embase, and Scopus, on April 8, 2024. Meta-analyses were performed for the mean change in intraocular pressure (IOP) at one-month, six-month, and one-year follow-up visits, rate of IOP spikes (>5 mmHg increase from the pre-procedure baseline IOP), rate of treatment failure (<20% or <3 mmHg reduction in IOP or requiring additional medications or procedures), and mean change in number of medications.

Results

Six studies, with a total of 593 eyes, were included: 283 underwent MLT, while 310 underwent SLT. A statistically significant difference in the efficacy of MLT versus SLT at one-month and six-month follow-ups was present, with SLT reducing IOP by 0.83 mmHg (95% CI: 0.20, 1.47; P = 0.01) more and 0.55 mmHg (95% CI: 0.02, 1.08; P = 0.04) more than MLT, respectively. At the one-year follow-up, there was no significant disparity in IOP reduction between SLT and MLT (WMD = 0.16; 95% CI: -0.40, 0.71; P = 0.58). There was a significantly lower rate of IOP spikes in the MLT treatment group (RR = 0.37; 95% CI: 0.16, 0.89; P = 0.03). There was no statistically significant difference in the rate of treatment failures (RR = 1.05; 95% CI: 0.68, 1.62; P = 0.84) or number of topical medications reduced (WMD = 0.06; 95% CI: -0.13, 0.26; P = 0.53).

Conclusion

While SLT may offer greater short-term reductions in IOP, it may be associated with more postoperative IOP spikes when compared to MLT. At one-year follow-up, there were no significant differences in IOP reduction or failure rates between the MLT and SLT groups.

[Factors affecting the hypotensive effect of selective laser trabeculoplasty in primary open-angle glaucoma]

PURPOSE

This study analyzes the influence of various factors on the hypotensive effect of selective laser trabeculoplasty (SLT) in patients with primary open-angle glaucoma (POAG).

MATERIAL AND METHODS

A retrospective study of the SLT effect was performed in 582 patients (756 eyes; mean age - 71.9±9.5 years) with POAG stages I-III. The level of intraocular pressure (IOP) decrease was assessed at 1 day, 1, 3, 6, and 12 months after SLT. The relationship between the hypotensive effect and age, gender, glaucoma stage, initial IOP level, number and type of instilled drugs, presence of intraocular lenses, and the surgeon performing the intervention were analyzed.

RESULTS

In the entire sample, the hypotensive effect of SLT after 1 day was 4.1±3.4 mm Hg, after 1, 3, 6, and 12 months - 3.7±4.8; 3.5±3.8; 3.1±3.4 and 2.3±3.8 mm Hg, respectively. The hypotensive effect of SLT was most dependent on the preoperative IOP level (R>0.64, p<0.05). No significant correlation was found between the hypotensive effect and the stage of POAG, gender, age, number of hypotensive drugs, phakia/aphakia, and the surgeon. A weaker hypotensive effect of SLT was found in eyes receiving monotherapy with α2-adrenoceptor agonists (p<0.03) and a combination of four drugs (p<0.02).

CONCLUSION

SLT is an effective method of additional IOP reduction in POAG at any stage and with any hypotensive regimen. At the same time, the results of its use in real clinical practice indicate the need for more careful IOP control after the procedure, especially in eyes with POAG stage III, as well as in eyes without hypotensive therapy and on the maximum drop regimen.

Alternatives to Topical Glaucoma Medication for Glaucoma Management

Topical glaucoma medications have favorable safety and efficacy, but their use is limited by factors such as side effects, nonadherence, costs, ocular surface disease, intraocular pressure fluctuations, diminished quality of life, and the inherent difficulty of penetrating the corneal surface. Although traditionally these limitations have been accepted as an inevitable part of glaucoma treatment, a rapidly-evolving arena of minimally invasive surgical and laser interventions has initiated the beginnings of a reevaluation of the glaucoma treatment paradigm. This reevaluation encompasses an overall shift away from the reactive, topical-medication-first default and a shift toward earlier intervention with laser or surgical therapies such as selective laser trabeculoplasty, sustained-release drug delivery, and micro-invasive glaucoma surgery. Aside from favorable safety, these interventions may have clinically important attributes such as consistent IOP control, cost-effectiveness, independence from patient adherence, prevention of disease progression, and improved quality of life.

Advanced glaucoma. Clinical practice guideline

OBJECTIVE

To present an update clinical practice guideline that serve as a guide for the detection, evaluation and treatment of adults patients with advanced glaucoma.

METHODS

After defining the objectives and scope of the guide, the working group was formed and structured clinical questions were formulated following the PICO (Patient, Intervention, Comparison, Outcomes) format. Once all the existing clinical evidence had been independently evaluated with the AMSTAR 2 (Assessment of Multiple systematic Rewiews) and Cochrane "Risk of bias" tools by at least two reviewers, recommendations were formulated following the Scottish Intercollegiate methodology. Guideline Network (SIGN).

RESULTS

Recommendations with their corresponding levels of evidence that may be useful in the diagnosis, monitoring and treatment of adults patients with advanced glaucoma.

CONCLUSIONS

Despite the fact that for many of the questions the level of scientific evidence available is not very high, this clinical practice guideline offers an updated review of the different existing aspects related to the evaluation and management of advanced glaucoma.

A Review of Selective Laser Trabeculoplasty: "The Hype Is Real"

Presently, there is no efficacious treatment for glaucomatous optic neuropathy; the current treatment is focused on lowering intraocular pressure (IOP). Studies have demonstrated the safety and efficacy of selective laser trabeculoplasty (SLT) in reducing the IOP in eyes with open-angle (OAG) glaucoma or ocular hypertension (OH). Moreover, the European Glaucoma Society has instated SLT as the first-line or adjunctive treatment in OAG or OH, reiterating its clinical significance. In this review, we outline the old and the new roles of SLT, with an emphasis on clinical practice, and look further into its renewed appeal and future developments.

Effect of Topical Dexmedetomidine (0.0055%) on Intraocular Pressure in Healthy Eyes: A Randomized Controlled Trial

Aim and objective

Evaluate the short-term safety and efficacy of dexmedetomidine (0.0055%) drops on intraocular pressure (IOP) in healthy eyes.

Materials and methods

In this randomized controlled trial, patients with normal eye exams were randomly assigned to receive, in a randomly selected eye, one drop of either balanced salt solution (BSS) or dexmedetomidine (0.0055%). Goldmann applanation tonometry was performed at baseline and then 30 minutes, 4 hours, and 24 hours after drop instillation.

Results

Forty-nine eyes of 49 normal volunteers were enrolled in the study, with 21 eyes (group I) receiving BSS and 28 (group II) dexmedetomidine. Both groups were comparable at baseline as far as age and IOP (p = 0.55 for both parameters). Intraocular pressure significantly decreased from baseline in group II at 30 minutes and 4 hours (p = 0.001 and 0.05, respectively). Maximum IOP decrease was obtained at 30 minutes after dexmedetomidine instillation, with a 9% decrease from baseline (mean decrease: 1.15 mm Hg). The percentage of IOP decrease was significantly higher in group II at 30 minutes compared with group I (9 vs 1.1%; p = 0.05). No side effects were recorded.

Conclusion

In this pilot study, dexmedetomidine 0.0055% drops have shown good safety and efficacy in lowering IOP in normal healthy volunteers with no history of glaucoma. This medication has a short onset of action, with a 10% reduction of IOP occurring 30 minutes post-instillation.

Trial registration number

NCT03690622.

How to cite this article

Fakhoury H, Abdelmassih Y, El-Khoury S, et al. The Effect of Topical Dexmedetomidine (0.0055%) on Intraocular Pressure in Healthy Eyes: A Randomized Controlled Trial. J Curr Glaucoma Pract 2021;15(2):58-63.

Selective Laser Trabeculoplasty in the Treatment of Ocular Hypertension and Open-Angle Glaucoma: Clinical Review

Selective laser trabeculoplasty (SLT) is a glaucoma treatment that reduces intraocular pressure (IOP). Its mechanism is based on the biological effects of the selective application of laser energy to pigmented trabecular meshwork (TM) cells, resulting in increased outflow facility. Herein, we review current publications on SLT and summarize its efficacy and safety for different indications in open-angle glaucoma (OAG) and ocular hypertension (OHT) treatment. SLT effectively reduces IOP when used as a primary treatment. In patients whose IOP is medically controlled, SLT helps to reduce medication use, and when maximally tolerated topical therapy is ineffective, SLT facilitates the realization of the target IOP. SLT is a repeatable procedure for which the vast majority of complications are mild and self-limiting. With effective IOP reduction, low complication rates and the potential to repeat the procedure, SLT offers the possibility of delaying the introduction of medical therapy and other more invasive treatment modalities while simultaneously avoiding the accompanying complications. With this knowledge, we suggest that SLT be considered as an essential primary treatment option in OAG and OHT, switching to other treatment modalities only when laser procedures are insufficient for achieving the required target IOP.

West Indies Glaucoma Laser Study (WIGLS) 3. Anterior Chamber Inflammation Following Selective Laser Trabeculoplasty in Afro-Caribbeans with Open-angle Glaucoma

PRECIS

In the absence of prophylactic anti-inflammatory therapy, anterior chamber inflammation (characterized by cells and less commonly flare) is minimal and transient after selective laser trabeculoplasty in Afro-Caribbean glaucoma patients.

PURPOSE

The purpose of this study was to characterize the prevalence, severity, and duration of anterior chamber inflammation (cells and flare) following selective laser trabeculoplasty (SLT) in Afro-Caribbean eyes with primary open-angle glaucoma (POAG).

METHODS

In total 144 eyes of 72 POAG patients underwent first-time 360-degree SLT treatment following washout of all topical medications in the prospective West Indies Glaucoma Laser Study. No anti-inflammatory therapy was used post-SLT. Anterior chamber cells and flare were characterized pre-SLT after medication washout, and 1 week, 6 weeks, and 3, 6, 9 and 12 months post-SLT using the standardized methodology described by the Society for Uveitis Nomenclature (SUN) in which cells and flare are each graded on a scale of 0-4+ using specific slit-lamp settings.

RESULTS

Mean cell scores in both right and left eyes rose significantly (P<0.0001) from baseline to week 1 after SLT before returning to baseline values at all subsequent time points. Mean flare scores in right eyes (P=0.0185) but not left eyes (P=0.1816) rose from baseline to week 1 after SLT before returning to baseline values at all subsequent time points. Cells appeared in 40.3% of eyes and flare appeared in 9.7% of eyes after SLT. One subject developed bilateral symptomatic anterior iritis one day postoperatively and reported a previously undisclosed history of recurrent iritis; the iritis resolved with topical steroid therapy.

CONCLUSIONS

SLT in Afro-Caribbean people with POAG is associated with mild, short-lived and self-limited anterior chamber inflammation. Routine anti-inflammatory therapy to suppress posttreatment inflammation after SLT is unnecessary in this population.

Postoperative pain following Descemet membrane endothelial keratoplasty (DMEK): a prospective study

PURPOSE

To evaluate postoperative pain following Descemet membrane endothelial keratoplasty (DMEK).

METHODS

Seventy-one patients completed perioperatively (day before surgery, day of surgery, 1st, 2nd, and 3rd day after surgery) four different questionnaires (a hospital internal protocol, QUIPS, PainDETECT®, and SF36) regarding their pain and other clinical parameters such as constipation, tiredness, vertigo, sleep disorders, concentration disorders, nausea, and emesis. All standardised questionnaires were evaluated to quantify average pain intensity as well as maximum pain intensity (NRS, 0 [no pain] to 10 [maximal pain], respectively). Analgesic treatment and intraocular pressure (IOP) during the perioperative stay were documented.

RESULTS

Mean average pain intensity was 0.70 ± 1.64 before surgery, 1.97 ± 2.05 on the day of surgery, 1.39 ± 1.68 on day 1, 0.87 ± 1.36 on day 2, and 0.81 ± 1.24 on day 3 after surgery. Maximum pain intensity was 0.65 ± 1.81 before surgery, 3.35 ± 2.98 on the day of surgery, 2.68 ± 2.99 on day 1, 1.49 ± 2.15 on day 2, and 1.26 ± 2.02 on day 3 after surgery. During the first three postoperative days, over 90% of the patients stated no or well tolerable pain. Eighty-three percent had postoperatively no need for analgesics at all. On the first two postoperative days, maximum IOP correlated significantly with reported increased maximum pain intensity (p = 0.043 and p = 0.029, respectively). All patients had very little problems with constipation, tiredness, vertigo, sleep disorder, concentration disorders, nausea, and emesis.

CONCLUSIONS

DMEK is associated with low postoperative pain intensity. Strong pain increase may indicate IOP elevation and should be further investigated and treated.

CLINICAL TRIAL REGISTRATION

German Clinical Trial Register (DRKS00013995).

Efficacy and safety of micropulse laser trabeculoplasty for primary open angle glaucoma

AIM

To evaluate the efficiency and safety of micropulse laser trabeculoplasty (MLT) for primary open angle glaucoma (POAG) patients.

METHODS

Retrospective study. POAG patients undergoing MLT in Peking University Third Hospital from June 2016 to November 2017. Seventy-two eyes of 72 POAG patients were enrolled. Only one eye of each patient was treated by MLT. The intraocular pressure (IOP) before MLT and at 1d, 1, 4, 12 and 24wk and glaucoma medication before and after treatment were compared.

RESULTS

The IOP was 20.6±5.9 mm Hg before MLT and 20.8±6.8 mm Hg at 2h after MTL. The IOP at 1d, 1, 4, 12 and 24wk was 17.9±4.4, 18.0±4.3, 17.5±3.4, 17.0±2.7, and 16.5±2.9 mm Hg, respectively. The IOP before and after MLT demonstrated a statistically significant difference by ANOVA analyses (F=5.797, P<0.001). Least significant difference t-tests showed there was no statistically significant difference between pre-MLT IOP within 2h after MLT (P=0.207). The statistically significant difference was confirmed between the pre-MLT IOP at 1d, 1, 4, 12 and 24wk after MLT (P=0.006, 0.009, 0.001, <0.001, <0.001, respectively). The number of glaucoma medications before MLT was 1.7±1.4 and 1.5±1.4 24wk after MLT with a significantly statistical difference (t=2.219, P=0.031).

CONCLUSION

MLT is effective and safe for POAG patients. No patient experienced IOP spikes after MLT. The IOP 6mo after treatment decreased significantly with less glaucoma medication.

Selective laser trabeculoplasty: past, present, and future

Over the past two decades, selective laser trabeculoplasty (SLT) has increasingly become an established laser treatment used to lower intraocular pressure in open-angle glaucoma and ocular hypertensive patients. In this review we trace the origins of SLT from previous argon laser trabeculoplasty and review the current role it has in clinical practice. We outline future directions of SLT research and introduce emerging technologies that are further developing this intervention in the treatment paradigm of glaucoma.

Could adverse effects and complications of selective laser trabeculoplasty be decreased by low-power laser therapy?

Selective laser trabeculoplasty (SLT) has been used for treatment of primary open-angle glaucoma, ocular hypertension, pigmenter and pseudoexfoliative glaucoma being considered a low-risk procedure. Therefore, transitory and permanent adverse effects have been reported, including corneal changes, subclinical edema, and reduction in endothelial cells and in central corneal thickness. Despite rarer, serious corneal complications after SLT can be permanent and lead to visual impairment, central corneal haze, opacity and narrowing. The mechanism involves increase of vasoactive and chemotactic cytokines causing inflammatory infiltrate, destruction of stromal collagen by fibroblasts and increase of matrix metalloproteinases type 2, which impair reepithelization. SLT also increases free radical production and reduces antioxidant enzymes, resulting in endothelium damages. Low-power laser therapy (LPLT) has been used in regenerative medicine based on its biostimulatory and anti-inflammatory effects. Biostimulation occurs through the interaction of laser photons with cytochrome C oxidase enzyme, which activates intracellular biochemical cascades causing synthesis of a number of molecules related to anti-inflammatory, regenerative effects, pain relief and reduction in edema. It has been showed that LPLT reduces gene expression related to pro-inflammatory cytokines and matrix metalloproteinases, and it increases expression of growth factors related to its proliferative and healing actions. Although radiations emitted by low-power lasers are considered safe and able to induce therapeutic effects, researches based on experimental models for glaucoma could bring important data if LPLT could be an alternative approach to improve acceptation for patients undergoing SLT.

Perioperative medications for preventing temporarily increased intraocular pressure after laser trabeculoplasty

BACKGROUND

Glaucoma is the international leading cause of irreversible blindness. Intraocular pressure (IOP) is the only currently known modifiable risk factor; it can be reduced by medications, incisional surgery, or laser trabeculoplasty (LTP). LTP reduces IOP by 25% to 30% from baseline, but early acute IOP elevation after LTP is a common adverse effect. Most of these IOP elevations are transient, but temporarily elevated IOP may cause further optic nerve damage, worsening of glaucoma requiring additional therapy, and permanent vision loss. Antihypertensive prophylaxis with medications such as acetazolamide, apraclonidine, brimonidine, dipivefrin, pilocarpine, and timolol have been recommended to blunt and treat the postoperative IOP spike and associated pain and discomfort. Conversely, other researchers have observed that early postoperative IOP rise happens regardless of whether people receive perioperative glaucoma medications. It is unclear whether perioperative administration of antiglaucoma medications may be helpful in preventing or reducing the occurrence of postoperative IOP elevation.

OBJECTIVES

To assess the effectiveness of medications administered perioperatively to prevent temporarily increased intraocular pressure (IOP) after laser trabeculoplasty (LTP) in people with open-angle glaucoma (OAG).

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 11), MEDLINE Ovid (1946 to 18 November 2016), Embase.com (1947 to 18 November 2016), PubMed (1948 to 18 November 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 18 November 2016), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com); last searched 17 September 2013, ClinicalTrials.gov (www.clinicaltrials.gov); searched 18 November 2016 and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 18 November 2016. We did not use any date or language restrictions.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in which participants with OAG received LTP. We included trials which compared any antiglaucoma medication with no medication, one type of antiglaucoma medication compared with another type of antiglaucoma medication, or different timings of medication.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened records retrieved by the database searches, assessed the risk of bias, and abstracted data. We graded the certainty of the evidence using GRADE.

MAIN RESULTS

We included 22 trials that analyzed 2112 participants and identified no ongoing trials. We performed several comparisons of outcomes: one comparison of any antiglaucoma medication versus no medication or placebo, three comparisons of one antiglaucoma medication versus a different antiglaucoma mediation, and one comparison of antiglaucoma medication given before LTP to the same antiglaucoma medication given after LTP. Only one of the included trials used selective laser trabeculoplasty (SLT); the remaining trials used argon laser trabeculoplasty (ALT). Risk of bias issues were primarily in detection bias, reporting bias, and other potential bias due to studies funded by industry. Two potentially relevant studies are awaiting classification due to needing translation.In the comparison of any medication versus no medication/placebo, there was moderate-certainty evidence that the medication group had a lower risk of IOP increase of 10 mmHg or greater within two hours compared with the no medication/placebo group (risk ratio (RR) 0.05, 95% confidence interval (CI) 0.01 to 0.20). This trend favoring medication continued between two and 24 hours, but the evidence was of low and very low-certainty for an IOP increase of 5 mmHg or greater (RR 0.17, 95% CI 0.09 to 0.31) and 10 mmHg or greater (RR 0.22, 95% CI 0.11 to 0.42). Medication was favored over placebo/no medication with moderate-certainty in reducing IOP from the pre-LTP measurements for both within two hours and between two and 24 hours. At two hours, the mean difference (MD) in IOP between the medication group and the placebo/no medication group was -7.43 mmHg (95% CI -10.60 to -4.27); at between two and 24 hours, the medication group had a mean reduction in IOP of 5.32 mmHg more than the mean change in the placebo/no medication group (95% CI -7.37 to -3.28). Conjunctival blanching was an ocular adverse effect that was more common when brimonidine was given perioperatively compared with placebo in three studies.In our comparison of brimonidine versus apraclonidine, neither medication resulted in a lower risk of increased IOP of 5 mmHg or greater two hours of surgery; however, we were very uncertain about the estimate. There may be a greater mean decrease in IOP within two hours after LTP. We were unable to perform any meta-analyses for other review outcomes for this comparison.In our comparison of apraclonidine versus pilocarpine, we had insufficient data to perform meta-analyses to estimate effects on either of the primary outcomes. There was moderate-certainty evidence that neither medication was favored based on the mean change in IOP measurements from pre-LTP to two hours after surgery.In the comparison of medication given before LTP versus the same medication given after LTP, we had insufficient data for meta-analysis of IOP increase within two hours. For the risk of IOP increase of 5 mmHg or greater and 10 mmHg or greater at time points between two and 24 hours, there was no advantage of medication administration before or after LTP regarding the proportion of participants with an IOP spike (5 mmHg or greater: RR 0.82, 95% CI 0.25 to 2.63; 10 mmHg or greater: RR 1.55, 95% CI 0.19 to 12.43). For an IOP increase of 10 mmHg or greater, we had very low-certainty in the estimate, it would likely change with data from new studies.

AUTHORS' CONCLUSIONS

Perioperative medications are superior to no medication or placebo to prevent IOP spikes during the first two hours and up to 24 hours after LTP, but some medications can cause temporary conjunctival blanching, a short-term cosmetic effect. Overall, perioperative treatment was well tolerated and safe. Alpha-2 agonists are useful in helping to prevent IOP increases after LTP, but it is unclear whether one medication in this class of drugs is better than another. There was no notable difference between apraclonidine and pilocarpine in the outcomes we were able to assess. Future research should include participants who have been using these antiglaucoma medications for daily treatment of glaucoma before LTP was performed.