Changes in macular function after ozurdex for retinal vein occlusion

Fundus-controlled perimetry (microperimetry): Application as outcome measure in clinical trials

Fundus-controlled perimetry (FCP, also called 'microperimetry') allows for spatially-resolved mapping of visual sensitivity and measurement of fixation stability, both in clinical practice as well as research. The accurate spatial characterization of visual function enabled by FCP can provide insightful information about disease severity and progression not reflected by best-corrected visual acuity in a large range of disorders. This is especially important for monitoring of retinal diseases that initially spare the central retina in earlier disease stages. Improved intra- and inter-session retest-variability through fundus-tracking and precise point-wise follow-up examinations even in patients with unstable fixation represent key advantages of these technique. The design of disease-specific test patterns and protocols reduces the burden of extensive and time-consuming FCP testing, permitting a more meaningful and focused application. Recent developments also allow for photoreceptor-specific testing through implementation of dark-adapted chromatic and photopic testing. A detailed understanding of the variety of available devices and test settings is a key prerequisite for the design and optimization of FCP protocols in future natural history studies and clinical trials. Accordingly, this review describes the theoretical and technical background of FCP, its prior application in clinical and research settings, data that qualify the application of FCP as an outcome measure in clinical trials as well as ongoing and future developments.

Guidelines for the Management of Retinal Vein Occlusion by the European Society of Retina Specialists (EURETINA)

The high prevalence of cardiovascular disease particularly in the elderly population is associated with retinal vascular disease. Retinal vein occlusions represent severe disturbances of the hypoxia-sensitive neurosensory retina. Acute and excessive leakage leads to the diagnostic hallmarks of retinal hemorrhage and edema with substantial retinal thickening. Advanced diagnostic tools such as OCT angiography allow to evaluate retinal ischemia and identify the risk for late complications and will soon reach clinical routine besides fluorescein angiography. Accordingly, the duration of non-perfusion is a crucial prognostic factor requiring timely therapeutic intervention. With immediate inhibition of vascular leakage, anti-VEGF substances excel as treatment of choice. Multiple clinical trials with optimal potential for functional benefit or a lesser regenerative spectrum have evaluated aflibercept, ranibizumab, and bevacizumab. As retinal vein occlusion is a chronic disease, long-term monitoring should be individualized to combine maintenance with practicability. While steroids may be considered in patients with systemic cardiovascular risk, surgery remains advisable only for very few patients. Destructive laser treatment is an option if reliable monitoring is not feasible. Ophthalmologists are also advised to perform a basic systemic workup to recognize systemic concomitants. The current edition of the EURETINA guidelines highlights the state-of-the-art recommendations based on the literature and expert opinions in retinal vein occlusion.

Analysis of Morphologic and Functional Outcomes in Macular Edema due to Central Retinal Vein Occlusion Treated with Intravitreal Dexamethasone Implant

Purpose

To analyze anatomic and functional retinal changes and their correlation after intravitreal dexamethasone implant (DEX implant) in patients with central retinal vein occlusion- (CRVO-) related macular edema (ME) using optical coherence tomography and microperimetry.

Methods

Fifteen treatment-naïve patients with functional impairment due to CRVO-related ME were enrolled in this prospective interventional case series. Main outcomes were best-corrected visual acuity (BCVA), retinal sensitivity (RS), and central retinal thickness (CRT). Secondary outcomes were ellipsoid zone (EZ) status and fixation behaviour. All patients underwent DEX implant and were retreated according to predefined criteria. Data were prospectively recorded at baseline and at month 1, 3, 6, 9, and 12. Correlation between main outcomes was analyzed.

Results

Fifteen eyes of 15 patients (9 men, 6 women; mean age 61.8 ± 10.9 years) were included. BCVA and CRT significantly improved at all follow-up visits, while RS significantly improved at 3, 6, 9, and 12 months. EZ status and fixation behaviour did not change significantly. Baseline CRT had a significant negative correlation with BCVA and RS at different follow-up visits (r=−0.52  to −0.63, p ≤ 0.04; r=−0.52, p=0.04; resp.). At all time points, there was not a significant correlation between CRT and BCVA and RS, while RS and BCVA showed a significant correlation, increasing over time (r=−0.72  to −0.89; p < 0.001).

Conclusion

DEX implant led to a significant morphofunctional improvement. Baseline CRT is predictive of changes of functional outcomes whose correlation increases over time after treatment.

Evaluation of the Effectiveness of Treatment with Dexamethasone Intravitreal Implant in Cystoid Macular Edema Secondary to Retinal Vein Occlusion

Purpose

To evaluate retinal functional improvement by means of visual acuity and retinal sensibility examination after intravitreal dexamethasone implant in patients affected by cystoid macular edema secondary to retinal vein occlusion.

Methods

Twenty-six consecutive patients affected by retinal vein occlusion complicated by cystoid macular edema were enrolled in this prospective interventional study. All patients underwent a baseline complete ophthalmological evaluation as well as retinal angiography, OCT examination, and microperimetry evaluation. Each patient was treated with intravitreal injection of a long-term steroid implant (Ozurdex, Allergan). Follow-up evaluations were performed at months 1, 3, and 6 and completed by OCT and MP1 examination. Clinical data underwent statistical analysis.

Results

Baseline functional evaluation showed mean visual acuity of 0,63±0,42 LogMAR and retinal sensitivity of 7,93±4,73 dB (mean±standard deviation); after treatment, at day 30 we found, respectively, 0,43±0,38 LogMAR (p<0.05, compared to baseline) and 10,15±4,410 dB (p<0.05); at day 90, we found 0,44±0,32 (p<0.05) and 9.61±4,29 dB (p<0.05); at day 180, we found 0,41±0,31 (p<0.05) and 9,95±3,79 dB (p<0.05). Fixation pattern improved significantly (p<0.05), showing a stable fixation in 30% of patients at baseline, increasing to 77% of patients at day 180. Baseline morphological evaluation showed a central retinal thickness (CRT) of 398,21±181,65 μm after treatment; we found a CRT of 222,64±95,21 μm at day 30 (p<0.05, compared to baseline), 307,50±120,25 μm (p<0.05) at day 90, and 294,93±135,86 μm (p<0.05) at day 180. About 15,3% patients showed already at month 3 a recurrence of macular edema. They underwent a retreatment before month 6 as for treatment guidelines.

Conclusion

Our detailed analysis showed the significative increase in retinal function in the early phases of the follow-up. Retinal sensibility showed a stronger correlation than VA in macular edema reabsorption, better underlying the progressive functional recovery and increase in quality of vision and life for the patients. This trial is registered with ClinicalTrials.gov NCT03559491.

OUTER RETINAL LAYER CHANGES AFTER DEXAMETHASONE IMPLANT FOR CENTRAL RETINAL VEIN OCCLUSION

PURPOSE

To analyze the outer retinal layer changes on spectral-domain optical coherence tomography after dexamethasone implant for the treatment of macular edema secondary to central retinal vein occlusions (CRVO).

METHODS

Thirty patients affected by macular edema related to CRVO (8 patients less than 50 years of age with nonischemic CRVO [<50-niCRVO], 12 patients more than 50 years with niCRVO [>50-niCRVO], and 10 patients with ischemic CRVO [iCRVO]) were included in a prospective study. After a comprehensive ophthalmologic examination, including best-corrected visual acuity, fluorescein angiography, and spectral-domain optical coherence tomography, each patient received a first implant. Further retreatments were performed on the basis of macular edema detection from the fourth month. Main outcome measure was the change in outer retinal layers at the 12-month examination.

RESULTS

The retinal layers of interest (external limiting membrane; ellipsoid zone; and retinal pigment epithelium) were classified as absent, disrupted, or present. The best baseline optical coherence tomography profile was found in <50-niCRVO group (absent external limiting membrane, ellipsoid zone, and retinal pigment epithelium layers in no patients; present and disrupted external limiting membrane in 25% and 75% of cases, respectively; disrupted ellipsoid zone and retinal pigment epithelium in 100% of cases), whereas the worst was detected in the iCRVO group (absent external limiting membrane, ellipsoid zone, and retinal pigment epithelium in 40%, 40%, and 10% of cases, respectively). A significant recovery of the retinal layers was observed in all CRVO subgroups; the greatest improvement was found in <50-niCRVO group. Median best-corrected visual acuity in the whole group improved from 0.85 to 0.45 (P = 0.0001). It is noteworthy that a significant best-corrected visual acuity gain was achieved only in eyes showing present or disrupted layers at baseline regardless of the CRVO subgroup examined, whereas eyes with absent layers at baseline were unable to attain any improvement.

CONCLUSION

Dexamethasone implant can promote the resolution of macular edema in patients affected by any CRVO subform, but a beneficial functional outcome could be achieved by eyes showing no absence of outer retinal layers on spectral-domain optical coherence tomography at baseline.

Retinal vein occlusion and the use of a dexamethasone intravitreal implant (Ozurdex®) in its treatment

Purpose

To review published data pertaining to the clinical experience with a dexamethasone intravitreal implant (Ozurdex®) with a view to establishing a clinically based therapeutic regime.

Methods

A PubMed search using the MeSH terms “retinal vein occlusion” and either “pathophysiology” or “dexamethasone intravitreal implant” was undertaken for manuscripts published until August 2015. The analysis included studies involving minimally 15 patients under a prospective design or 30 under a retrospective design, a minimal follow up of 6 months, and at least 2 intravitreal Ozurdex® injections per eye.

Results

In the vast majority of eyes, satisfactory outcomes were achieved with retreatment intervals of between 3 and 5 months. Initial evidence indicates a similar efficacy compared to anti-VEGF therapies as a first-line treatment. Safety concerns associated with the long-term and repeated use of Ozurdex® are not borne out by clinical findings: its implantation is not associated with a sustained increase in intraocular pressure (IOP) over time or with the number of applications.

Conclusion

Compared with anti-VEGF therapies, the burden of retreatment is reduced. In patients with chronic macular edema not responsive to repetitive anti-VEGF therapies, the outcome after dexamethasone implant treatment is encouraging. However, these results are achieved at the expense of side effects typically associated with steroids: in up to 20 % of the Ozurdex®-treated patients, an elevation in IOP, which could be medically controlled in the majority of cases, and cataract formation or progression was observed.

Morphology and Function over a One-Year Follow Up Period after Intravitreal Dexamethasone Implant (Ozurdex) in Patients with Diabetic Macular Edema

Background

To investigate changes in macular morphology and function after an intravitreal dexamethasone implant for diabetic macular edema (DME).

Methods

Twenty-seven eyes in 27 treatment-naive patients affected by DME were treated with intravitreal Ozurdex® injections (IVOI) and followed up 12 months to evaluate morphological and functional changes by means of best-corrected visual acuity (BCVA), microperimetry (MP1), multifocal electroretinography (mfERG), pattern electroretinography (PERG) and spectral domain optical coherence tomography (SD-OCT).

Results

Both BCVA and retinal sensitivity improved significantly at one month after the IVOI (p = 0.031 and p<0.0001, respectively). After five months, the improvement of BCVA remained statistically significant compared with baseline values (p = 0.022); retinal sensitivity improvement was statistically significant for up to four months after the IVOI (p = 0.059). Moreover, central macular thickness significantly decreased for up to four months. Interestingly, PERG and mfERG values did not change significantly for up to four months post-IVOI, but then began to worsen.

Conclusions

In eyes with DME, intravitreal dexamethasone implant determined morphological and functional improvement as soon as one month and for up to four months after the treatment.