[Anterior chamber migration of intravitreal dexamethasone implant (Ozurdex®) in pseudophakic eyes: report of three cases]

From randomised controlled trials to real-world data: Clinical evidence to guide management of diabetic macular oedema

Randomised clinical trials (RCTs) are generally considered the gold-standard for providing scientific evidence for treatments' effectiveness and safety but their findings may not always be generalisable to the broader population treated in routine clinical practice. RCTs include highly selected patient populations that fit specific inclusion and exclusion criteria. Although they may have a lower level of certainty than RCTs on the evidence hierarchy, real-world data (RWD), such as observational studies, registries and databases, provide real-world evidence (RWE) that can complement RCTs. For example, RWE may help satisfy requirements for a new indication of an already approved drug and help us better understand long-term treatment effectiveness, safety and patterns of use in clinical practice. Many countries have set up registries, observational studies and databases containing information on patients with retinal diseases, such as diabetic macular oedema (DMO). These DMO RWD have produced significant clinical evidence in the past decade that has changed the management of DMO. RWD and medico-administrative databases are a useful resource to identify low frequency safety signals. They often have long-term follow-up with a large number of patients and minimal exclusion criteria. We will discuss improvements in healthcare information exchange technologies, such as blockchain technology and FHIR (Fast Healthcare Interoperability Resources), which will connect and extend databases already available. These registries can be linked with existing or emerging retinal imaging modalities using artificial intelligence to aid diagnosis, treatment decisions and provide prognostic information. The results of RCTs and RWE are combined to provide evidence-based guidelines.

Review of Risk Factors and Complications of Anterior Migration of Ozurdex Implant: Lessons Learnt from the Previous Reports

Purpose: Ozurdex had shown promising anatomical and functional outcomes in managing refractory Irvine-Gass syndrome over the years. Burgeoning usage of Ozurdex has prompted the study of its related complications, particularly the anterior chamber migration of the implant. Methods: Literature reviews on the anterior chamber migration of the Ozurdex via PubMed, EBSCO, and TRIP databases were searched from 2012 to 2020. The predisposing factors, outcomes, and management of such cases were evaluated. Results: A total of 54 articles consisting of 105 cases of anterior migration of Ozurdex were included in this analysis. The vitrectomized eye and compromised posterior capsule were highly associated with this complication. About 81.9% of the cases had cornea edema upon presentation, with 31.4% of them ending up with cornea decompensation despite intervention. Although there was high intraocular pressure reported initially in 22 cases, only 2 cases required glaucoma filtration surgeries in which they had preexisting glaucoma. Numerous techniques of repositioning or surgical removal of the implant were described but they were challenging and the outcomes varied. Conclusions: A noninvasive method of manipulating the Ozurdex into the vitreous cavity via the "Trendelenburg position, external pressure with head positioning" maneuvers is safe yet achieves a favorable outcome. Precaution must be taken whenever offering Ozurdex to the high-risk eyes. Prompt repositioning or removal of the implant is crucial to deter cornea decompensation. Clinical Trial Registration number: NMRR-22-02092-S9X (from the Medical Research and Ethics Committee (MREC), Ministry of Health, Malaysia).

Anterior Chamber Migration of Ozurdex Implants

We present patient characteristics and follow-up results of cases with anterior chamber dexamethasone implant migration. The common feature of all six presented cases was vitrectomized eyes. Four of the patients had sutured intraocular lens (IOL) implantation due to complicated cataract surgery, one had combined retinal detachment surgery with sutured IOL implantation, and one had vitrectomy for diabetic intravitreal hemorrhage cleaning and uncomplicated cataract surgery. Anterior chamber implant migration caused corneal edema in all cases and elevated intraocular pressure in three cases. In two cases, the dexamethasone implant was directed into the vitreous cavity after maximum pupillary dilation and corneal manipulation with cotton tip applicator with the patient in reverse Trendelenburg position. There was no other complication until dexamethasone implant degradation, with clear cornea at final examination. In two cases, the implant was removed from the anterior chamber by aspiration, but keratoplasty surgery was planned due to endothelial cell loss and persistent corneal edema during follow-up. In the last two cases, the dexamethasone implant was redirected into the vitreous chamber with a 23-gauge catheter and anterior chamber maintainer but they migrated into the anterior chamber again. In one of these patients, the implant was aspirated by catheter and corneal transplantation was performed due to corneal edema, while the other patient’s implant was redirected into the vitreous chamber with no further anterior migration. The risk of dexamethasone implants migrating into the anterior chamber of vitrectomized eyes and those with sutured IOL implantation should be kept in mind and the patient should be informed and advised to see an ophthalmologist immediately before permanent corneal endothelial damage occurs.

Guidelines for the Management of Center-Involving Diabetic Macular Edema: Treatment Options and Patient Monitorization

Diabetic macular edema (DME) is the main cause of visual impairment associated with diabetic retinopathy (DR) and macular laser, during approximately three decades, and was the single treatment option. More recently, intravitreous injections of anti-angiogenics and corticosteroids modified the treatment paradigm associated with significant vision improvements. Nevertheless, not all patients respond satisfactorily to anti-VEGF or corticosteroid injections, so an adequate treatment choice and a prompt switch in therapeutic class is recommended. Several algorithms and guidelines have been proposed for treating center involving DME to improve patients’ vision and quality of life. However, in Portugal, such guidelines are lacking. The present review aimed to provide guidelines for the treatment options and patient monitorization in the management of center-involving DME. We recommend anti-vascular endothelial growth factor (VEGF) as first-line therapy after a clinical evaluation accompanied by a rigorous metabolic control. Depending on the response obtained after 3–6 monthly intravitreal injections we suggest switching outside the class in case of a non-responder, maintaining the anti-VEGF-therapy in responders to anti-angiogenics. The treatment regimen for Dexamethasone intravitreal implant (DEXii) should be pro-re-nata with bi-monthly or quarterly monitoring visits (with a scheduled visit at 6–8 weeks after DEXii for intraocular pressure control). If a patient does not respond to DEXii, switch again to anti-VEGF therapy, combine therapies, or re-evaluate patients diagnose. There is a resilient need to understand the disease, its treatments, regimens available, and convenience for all involved to propose an adequate algorithm for the treatment of diabetic retinopathy (DR) and DME in an individualized regimen. Further understanding of the contributing factors to the development and progression of DR should bring new drug discoveries for more effective and better-tolerated treatments.

Tiny dexamethasone palmitate nanoparticles for intravitreal injection: Optimization and in vivo evaluation

Tiny nanoparticles of dexamethasone palmitate (DXP) were designed as transparent suspensions for intravitreal administration to treat age-related macular degeneration (AMD). The influence of three surfactants (PEG-40-stearate and Pluronic block copolymers F68 and F127) on nanoparticles size and stability was investigated and led to an optimal formulation based on Pluronic F127 stabilizing DXP nanoparticles. Size measurements and TEM revealed tiny nanoparticles (around 35 nm) with a low opacity, compatible with further intravitreal injection. X-Ray powder diffraction (XRPD) and transmission electronic microscopy (TEM) performed on freeze-dried samples showed that DXP nanoparticles were rather monodisperse and amorphous. The efficacy of DXP nanoparticles was assessed in vivo on pigmented rabbits with unilateral intravitreal injections. After breakdown of the blood-retinal barrier (BRB) induced by injection of rhVEGF165 with carrier protein, DXP nanoparticles induced a restoration of the BRB 1 month after their intravitreal injection. However, their efficacy was limited in time most probably by clearance of DXP nanoparticles after 2 months due to their small size.

Disloziertes Dexamethason-Implantat in der Vorderkammer: ein Fallbericht

Hintergrund

Ozurdex® (Allergan Pharmaceuticals Ireland, Westport, Co. Mayo, Irland) ist ein intravitreales Implantat von 700 mcg Dexamethason, das für die Behandlung eines Makulaödems infolge eines retinalen Venenverschlusses, einer nichtinfektiösen posterioren Uveitis und einer diabetischen Makulopathie zugelassen ist. Erhöhter Augeninnendruck sowie Trübungen der kristallinen Linse sind bekannte Komplikationen. Seltener wird in der Literatur auch die unerwünschte Migration des Implantates in die Vorderkammer (VK) beschrieben. Laut Literatur erforderten die meisten Implantatdislokationen in die VK eine operative Entfernung oder Reposition in den Glaskörperraum. Wir berichten die erfolgreiche Repositionierung eines Ozurdex®-Implantats durch die medikamentöse Erweiterung der Pupille.

Falldarstellung

Eine 79-jährige Patientin entwickelte nach einer sekundären Intraokularlinsenimplantation ein persistierendes zystoides Makulaödem am linken Auge. Dieses wurde seit 3 Jahren mit intravitrealem Ozurdex® behandelt. Bei der geplanten Kontrolle 4 Wochen nach der letzten Behandlung wurde das Ozurdex®-Stäbchen in der VK zwischen Iris und Optik der Vorderkammerlinse (VKL) festgestellt. Es erfolgte eine medikamentöse Erweiterung der Pupille, um das dislozierte Stäbchen zu mobilisieren. Die anschließende Spaltlampenuntersuchung und Fundoskopie zeigten eine Rücklagerung des Ozurdex®-Implantates in dem Glaskörperraum.

Schlussfolgerungen

Die Entfernung des Ozurdex®-Stäbchens aus der VK ist notwendig, um eine Dekompensation des Hornhautendothels zu vermeiden. Wir empfehlen vor einer chirurgischen Intervention einen Repositionsversuch des Implantats durch die medikamentöse Erweiterung der Pupille.

Macular edema associated with non-infectious uveitis: pathophysiology, etiology, prevalence, impact and management challenges

Macular edema (ME) is the most common sight-threatening complication in uveitis. The diagnostic and therapeutic management of the uveitic macular edema (UME) might be challenging due to the complex diagnostic workup and the difficulties physicians face to find the underlying cause, and due to its usually recurrent nature and the fact that it can be refractory to conventional treatment. Some of the mild cases can be treated with topical steroids, which can be combined with non-steroid anti-inflammatory drugs. However, immunomodulators such as methotrexate, tacrolimus, azathioprine, cyclosporine and mycophenolate mofetil together with anti-tumor necrosis factor-α (anti-TNF alpha) monoclonal antibodies such as adalimumab and infliximab, may be required to control the inflammation and the associated ME in refractory cases, or when an underlying disease is present. This review of the literature will focus mostly on the non-infectious UME.

First-line treatment algorithm and guidelines in center-involving diabetic macular edema

Management of center-involving diabetic macular edema represents a real therapeutic challenge. Diabetic macular edema is the leading cause of visual acuity impairment in diabetic patients. Since the advent of intravitreal drugs, management of diabetic macular edema has significantly evolved. The historical grid laser photocoagulation is no longer recommended as first-line treatment of diabetic macular edema owing to the findings of the pivotal randomized controlled trials, and anti-vascular endothelial growth factor therapy has emerged as first-line therapy. Steroids also represent a valid treatment option in the management of naïve diabetic macular edema and their efficacy has also been confirmed in several studies. The optimal treatment for diabetic macular edema should consider both general and ophthalmological comorbidities. Patient compliance and motivation should also be carefully evaluated as some treatments require monthly follow-up. Based on recent literature evidence, the present review provides clinicians with a first-line treatment algorithm for center-involving diabetic macular edema tailored to the patient’s individual characteristics.

Anterior chamber migration of a sustained-release dexamethasone intravitreal implant: A case report and review of literature

The purpose of the study was to report a case of migration of a dexamethasone intravitreal implant (Ozurdex^®) into anterior chamber and review the literature pertaining to the anterior chamber migration of implant. Clinical data were collected from a patient, in whom a dexamethasone intravitreal implant migrated to anterior chamber. A review of literature was conducted to analyze additional reports. A 59-year-old aphakic patient with recalcitrant cystoid macular edema due to chronic idiopathic uveitis was treated with intravitreal injection of dexamethasone implant. Migration of the implant into anterior chamber was noted after a month of injection. Since his cornea was clear and intraocular pressure was normal, he was managed conservatively. Sixteen such reports of migration of implant into anterior chamber was analyzed to look into the possible etiologies and outcome. Disruption of lens capsule, large basal iridectomy, and prior vitrectomy are the primary risk factors for migration of dexamethasone implant into the anterior chamber.

Uneventful Anterior Migration of Intravitreal Ozurdex Implant in a Patient with Iris-Sutured Intraocular Lens and Descemet Stripping Automated Endothelial Keratoplasty

Purpose

We report here the case of a patient with anterior segment migration of intravitreal dexamethasone implant as well as its management and outcome.

Methods

The patient had the following sequence of events: complicated cataract surgery, iris-sutured intraocular lens implant, followed by cystoid macular edema treated with intravitreal Avastin, retinal vein occlusion treated with intravitreal dexamethasone implant, corneal decompensation treated with Descemet stripping automated endothelial keratoplasty (DSAEK), and finally recurrence of macular edema treated with repeated intravitreal dexamethasone implant.

Results

Dexamethasone implant had completely dissolved from the eye 12 weeks after insertion without any complication.

Conclusion

A conservative approach with regular monitoring in the situation of a quiet anterior segment without any corneal decompensation can provide enough time for the implant to dissolve without causing any complication to the involved eye, avoiding any additional surgical intervention, as presented in this case report. Despite the fact that the implant was left for natural dissolution, there were no adverse effects related to the graft or the eye.

Anterior segment migration of dexamethasone implant: risk factors, complications, and management

PURPOSE OF REVIEW

To describe the risk factors, clinical course, and complications related to anterior segment migration of a dexamethasone (DEX) intravitreal implant, and review over potential management strategies.

RECENT FINDINGS

Recent reports have demonstrated that migration of a DEX implant into the anterior chamber may occur in patients with higher risk ocular characteristics. Although a relatively rare occurrence, DEX implant migration carries the possibility of inducing potentially vision-threatening corneal endothelial decompensation and edema.

SUMMARY

Any combination of previous pars plana vitrectomy, an open/defective lens capsule, and/or iris defects may increase the risk of DEX implant migration into the anterior chamber. In the setting of a DEX implant that has moved into the anterior segment with corneal edema already present, urgent removal of the implant is warranted to reduce the risk of permanent visual compromise.

Management of anterior chamber dislocation of a dexamethasone intravitreal implant: a case report

Background

Ozurdex is a 700 mcg dexamethasone intravitreal implant, approved for the management of macular edema secondary to retinal vein occlusion, and other related pathoglogiesAnterior chamber dislocation of Ozurdex represents an uncommon complication of the intravitreal injection, which can be managed by repositioning the implant into the vitreous cavity. We describe the case of a successful repositioning of an Ozurdex implant by mobilization and subsequent balanced saline solution injection in the anterior chamber.

Case presentation

An 83-year-old white woman presented to our Emergency Unit complaining of pain and vision loss in herright eye lasting a week. Her anamnesis revealed a history of persistent cystoid macular edema after phacoemulsification with scleral-fixated posterior chamber intraocular lens implantation, recently treated with an intravitreal Ozurdex implant. She also took a long-distance flight 2 days after the injection.

An anterior segment examination showed corneal edema and the rod implant adherent to corneal endothelium. To avoid corneal decompensation, we opted for a implant repositioning. Under topical anesthesia, a 30-gauge needle was introduced through a limbar incisionto mobilize the dislocated rod. Balanced saline solution was injected, with a successful repositioning of the implant into the vitreous cavity. Topical 5 % hypertonic saline solution and 0.2 % betamethasone associated with 0.5 % chloramphenicol drops were administered four times a day. To prevent redislocation of the Ozurdex implant, she was instructed to avoid prone position, any kind of physical effort, and not to undertake long-distance flights during the first postoperative week. One week after surgery, an anterior segment examination showed an improvement of corneal edema. Funduscopy showed that the Ozurdex implant was settled into the vitreous cavity.

Conclusions

Anterior chamber dislocation of Ozurdex from the vitreous cavity is rare. In our patient, in addition to the posterior capsule tearing, the long-distance flight could have contributed to implant dislocation. Repositioning of the implant is necessary to avoid endothelial decompensation. It can be carried out by using saline balanced solution with the same efficacy as other surgical procedures reported in the literature. A possible disadvantage of this procedure could be implant migration.

Corneal toxicity after Ozurdex(®) migration into anterior chamber

OBJECTIVE

To describe a case of corneal toxicity after migration of a dexamethasone implant into the anterior chamber.

CASE REPORT

A 62-year-old man with aphakia and a history of vitrectomy received a dexamethasone implant for a refractory Irvine-Gass syndrome. Thirty days later, the implant migrated into the anterior chamber causing endothelial contact with secondary corneal oedema that justified the removal of the implant without resolution of the oedema.

DISCUSSION

Clinical tolerability to dislocated implant is poor in cases with pre-existing corneal oedema, and because of this, it must be removed early. In cases of aphakia and vitrectomy, the increased risk of Ozurdex(®) dislocation justifies performing a prior endothelial count.

[Tolerability and short-term efficacy of the Ozurdex® dexamethasone intravitreal implant for treatment of uveitic cystoid macular edema: A retrospective study of 52 injections performed at the Clermont-Ferrand teaching hospital]

Macular edema is the main cause of decreased visual acuity in uveitis and determines the visual prognosis. We retrospectively analyzed the tolerability and efficacy of the dexamethasone intravitreal implant in the management of uveitis. Twenty-five patients with uveitic cystoid macular edema were all treated with the Ozurdex(®) dexamethasone intravitreal implant from January 2012 to August 2014. The main outcome measures were visual acuity recovery, changes in macular thickness and resolution of the vitritis. Thirty-two eyes of 25 patients received 52 injections of Ozurdex(®). Both complete regression of the macular edema and resolution of the vitritis occurred in 100 % patients. Visual acuity improved in 62 % of patients: the mean reduction in macular thickness was 252 (±171μm); the mean time between injections was 6.7 (±3.8) months. Secondary ocular hypertension was seen in 33 % of patients. No patient required secondary surgery although a selective laser trabeculoplasty was required for one patient. The dexamethasone intravitreal implant Ozurdex(®) resulted in continuous and complete regression of uveitic cystoid macular edema. It allows evaluation of the potential visual recovery of treated eyes. The tolerability and duration of action provide a rationale for considering Ozurdex(®) as a first-line therapy for uveitis which remains uncontrolled despite optimal systemic treatment.

Receiver operating characteristic curve to predict anti-VEGF resistance in retinal vein occlusions and efficacy of Ozurdex

PURPOSE

Current treatment paradigms for macular edema associated with retinal vein occlusions (RVO) often involve initial treatment with anti-vascular endothelial growth factor (VEGF) agents, then switching to intravitreal dexamethasone implant (IDI; Ozurdex, Allergan, Parsippany, NJ) for poor responders. However, many patients undergo multiple injections prior to being declared a nonresponder. We devised a method for prediction of poor anti-VEGF response after one injection, and show that these patients subsequently respond well to IDI.

METHODS

This study is a retrospective consecutive interventional case series of patients with RVO receiving anti-VEGF agents that were switched to IDI. Patients were categorized as nonresponders to anti-VEGF agents (edema did not improve) or responders (edema improved, but switched to IDI for longer treatment duration). Receiver operating characteristics (ROC) curve analysis was used to determine cutoffs of reduction in central retinal thickness (CRT) to predict poor response to anti-VEGF treatment.

RESULTS

Twenty-three patients met inclusion criteria. There were 14 nonresponders and 9 responders. The ROC curve analysis found that the maximal sensitivity and specificity in correctly identifying responders to anti-VEGF therapy was those with >25% reduction in CRT 1 month after 1 anti-VEGF treatment (sensitivity 0.89, specificity 0.79, area under the curve 0.93). After IDI placement, anti-VEGF nonresponders showed significant improvement in visual acuity (VA) (p = 0.02) and CRT (p = 0.01).

CONCLUSIONS

In patients with macular edema secondary to RVOs, a reduction in CRT by ≤25%, 1 month after 1 anti-VEGF injection, is predictive of poor response to anti-VEGF treatment. These patients may benefit from earlier conversion to IDI treatment, which in our study, resulted in improved VA and CRT.

Perspective on the role of Ozurdex (dexamethasone intravitreal implant) in the management of diabetic macular oedema

Diabetic macular oedema (DMO) is the most common cause of visual loss in the working age population. Intravitreal therapy has superseded macular laser as the first-line treatment for the management of centre-involving DMO in most patients. As well as the proven efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents, phase II and III clinical trials of Ozurdex intravitreal dexamethasone implants for DMO have also demonstrated a mean increase in visual acuity and corresponding mean reduction in central macular thickness, particularly in pseudophakic eyes. Because of the risk of visual loss from cataract, glaucoma and intraocular infection with the use of intravitreal steroids, Ozurdex tends to be reserved for use in patients unresponsive to anti-VEGF therapy for centre-involving DMO. Situations where Ozurdex may be considered a first-line treatment option for eyes with centre-involving DMO include pseudophakia, impending cataract surgery, or in the context of a recent arterial thromboembolic event. Because of their stable pharmacokinetics, Ozurdex slow-release implants may also be considered in vitrectomized eyes.

Dexamethasone intravitreal implant in the treatment of diabetic macular edema

Diabetic macular edema (DME) resembles a chronic, low-grade inflammatory reaction, and is characterized by blood–retinal barrier (BRB) breakdown and retinal capillary leakage. Corticosteroids are of therapeutic benefit because of their anti-inflammatory, antiangiogenic, and BRB-stabilizing properties. Delivery modes include periocular and intravitreal (via pars plana) injection. To offset the short intravitreal half-life of corticosteroid solutions (~3 hours) and the need for frequent intravitreal injections, sustained-release intravitreal corticosteroid implants have been developed. Dexamethasone intravitreal implant provides retinal drug delivery for ≤6 months and recently has been approved for use in the treatment of DME. Pooled findings (n=1,048) from two large-scale, randomized Phase III trials indicated that dexamethasone intravitreal implant (0.35 mg and 0.7 mg) administered at ≥6-month intervals produced sustained improvements in best-corrected visual acuity (BCVA) and macular edema. Significantly more patients showed a ≥15-letter gain in BCVA at 3 years with dexamethasone intravitreal implant 0.35 mg and 0.7 mg than with sham injection (18.4% and 22.2% vs 12.0%). Anatomical assessments showed rapid and sustained reductions in macular edema and slowing of retinopathy progression. Phase II study findings suggest that dexamethasone intravitreal implant is effective in focal, cystoid, and diffuse DME, in vitrectomized eyes, and in combination with laser therapy. Ocular complications of dexamethasone intravitreal implant in Phase III trials included cataract-related events (66.0% in phakic patients), intraocular pressure elevation ≥25 mmHg (29.7%), conjunctival hemorrhage (23.5%), vitreous hemorrhage (10.0%), macular fibrosis (8.3%), conjunctival hyperemia (7.2%), eye pain (6.1%), vitreous detachment (5.8%), and dry eye (5.8%); injection-related complications (eg, retinal tear/detachment, vitreous loss, endophthalmitis) were infrequent (<2%). Dexamethasone intravitreal implant offers a viable treatment option for DME, especially in cases that are persistent or treatment (anti-vascular endothelial growth factor/laser) refractory.

Post-operative refractory cystoid macular edema in a vitrectomized eye treated with slow-release dexamethasone implant (Ozurdex)

INTRODUCTION

The use of a slow-release dexamethasone implant (Ozurdex) for the treatment of post-operative macular edema (ME) in a vitrectomized eye has never been used before. We herein report a case of a 70-year-old woman with post-vitrectomy ME refractory to topical, sub-tenon's and intravitreal steroid administration that responded well to the implantation of a slow-release dexamethasone implant (Ozurdex) in a previously vitrectomized eye.

METHODS

Interventional case presentation.

RESULTS

One week post-implantation, the central retinal thickness was reduced to 383 μm from 640 μm and the best corrected visual acuity (BCVA) improved to 6/36 from counting fingers (CF). At six months' follow-up visit, the improvement of the ME was sustained as indicated by the optical coherence tomography (OCT) measurements and the BCVA remained stable. No serious topical or systemic adverse events were observed from the implantation of Ozurdex in the vitrectomized eye.

CONCLUSION

The use of Ozurdex in our case resulted in rapid improvement of the post-operative resistant ME. To the best of our knowledge, this is the first report in the literature demonstrating the use of the slow-release dexamethasone implant (Ozurdex) to treat post-operative ME in a vitrectomized eye.