Intravitreal gas for symptomatic vitreomacular adhesion: a synthesis of the literature

Calculating the individual probability of successful ocriplasmin treatment in eyes with vitreomacular traction–Validation and refinement of a multivariable prediction model

Purpose

To evaluate a multivariable model predicting the individual probability of successful intravitreal ocriplasmin (IVO) treatment in eyes with vitreomacular traction (VMT).

Methods

Data from three prospective, multicenter IVO studies (OASIS, ORBIT, and INJECT) were pooled. Patients were included if they were treated for a symptomatic VMT without a full-thickness macular hole. A prediction model for VMT resolution using the factors ‘age’ and ‘horizontal VMT diameter’ was validated by receiver operating characteristic analysis and according to grouped prediction after calibration. Multivariable regression analysis was performed to check robustness and explore further improvements.

Results

Data from 591 eyes was included. In the univariate analysis all key factors (age, gender, VMT diameter, lens status, ERM) significantly correlated to treatment success. The prediction model was robust and clinically applicable to estimate the success rate of IVO treatment (AUC of ROC: 0.70). A refinement of the model was achieved through a calibration process.

Conclusion

The developed multivariable model using ‘horizontal VMT diameter’ and ‘age’ is a valid tool for prediction of VMT resolution upon IVO treatment.

Effect of pneumatic vitreolysis in management of patients with symptomatic focal vitreomacular traction

PURPOSE

To evaluate the efficacy of single intravitreal injection of an expansile concentration of sulphur hexafluoride gas (SF6) in treating patients with symptomatic focal vitreomacular traction (VMT) documented by spectral domain optical coherence tomography (SD-OCT) preoperatively.

METHODS

This is a prospective interventional case series including 30 eyes of 29 patients with symptomatic focal VMT evident on SD-OCT. Pre-operatively, mean best corrected visual acuity (BCVA) was 20/125 (range 20/400-20/40). Mean central foveal thickness (CFT) was 382 μm (range 149-576 μm; SD ± 91.88). All eyes received single intravitreal injection of 0.3 mL of 100% SF6 gas. Postoperatively, we performed SD-OCT at one week, one month, and three months for all eyes. Primary outcome measure was release of VMT. Secondary outcome measures were changes in postoperative BCVA andCFT.

RESULTS

Overall, VMT release occurred in 24 of 30 eyes by the final follow-up visit (80% final release rate); furthermore, 76.9% of eyes with diabetic maculopathy and 25% of eyes with concurrent epiretinal membrane (ERM) had successful VMT release. VMT release was documented on SD-OCT at an average of 3 weeks (range, 1-12 weeks). The rate of release in phakic eyes was 90% (18 of 20 eyes) versus 60% in pseudophakic eyes (6 of 10 eyes). One patient developed a retinal break at upper nasal retina after two weeks of injection.

CONCLUSION

Pneumatic vitreolysis (PVL) with limited face-down position is a viable option for treating focal VMT with few adverse events. Further studies are needed to evaluate its indications, benefits, and risks.

Efficacy and Safety of Ocriplasmin Use for Vitreomacular Adhesion and Its Predictive Factors: A Systematic Review and Meta-Analysis

Symptomatic vitreomacular adhesion (sVMA) impedes visual acuity and quality. Ocriplasmin is a recombinant protease, which may be injected into the vitreous cavity to treat this condition, yet controversy remains with respect to its effectiveness and safety, particularly its patient selection standard. In this systematic review, the PubMed, Embase, and the Cochrane Library were searched to identify studies published prior to August 2020 on the impact of ocriplasmin treatment on VMA release, macular hole (MH) closure, and/or related adverse events (AEs). Data were pooled using a random-effects model. Risk ratios (RRs) with 95% CIs were calculated. Of 1,186 articles reviewed, 5 randomized controlled trials and 50 cohort studies were ultimately included, representing 4,159 patients. Ocriplasmin significantly increased the rate of VMA release (RR, 3.61; 95% CI, 1.99–6.53; 28 days after treatment) and MH closure (RR, 3.84; 95% CI, 1.62–9.08; 28 days after treatment) and was associated with visual function improvement. No increased risk for overall AEs was seen in ocriplasmin treatment. The proportion of VMA release and MH closure in patients was 0.50 and 0.36, respectively. VMA release was more likely in patients with absence of epiretinal membrane (ERM). Patients with smaller MH diameter were more likely to achieve MH closure. Evidence from included studies suggests that ocriplasmin is a suitable and safe approach for treating sVMA. ERM and MH status are important factors when considering ocriplasmin treatment.

Anatomical and functional outcomes of pneumatic vitreolysis for treatment of vitreomacular traction with and without macular holes

PURPOSE

To evaluate the outcome of pneumatic vitreolysis (PVL) for vitreomacular traction (VMT) with or without full thickness macular hole (MH) < 400 µm.

METHODS

Forty-seven eyes of 47 patients were included who had undergone PVL for VMT with or without MH. Main outcome measures were release of VMT, MH closure, best-corrected visual acuity (BCVA) and adverse events.

RESULTS

Thirty-three patients had isolated VMT and 14 patients VMT with a MH. Four weeks after PVL, the overall VMT release rate was 35/47 (74.5%): 25/37 (67.6%) in phakic and 10/10 (100%) in pseudophakic eyes (p = 0.03). Four of 14 MH (28.6%) were closed. Twenty-two of 47 (46.8%) eyes required a subsequent PPV: 12/33 (36.4%) in the VMT only group and 10/14 (71.4%) in the VMT with MH group. Mean BCVA improved from 0.48 (± 0.24) to 0.34 (± 0.23) logMAR at 6 months in patients with VMT alone (p < 0.001), and from 0.57 (± 0.27) to 0.41 (± 0.28) logMAR in patients with VMT and MH (p = 0.008). Adverse events included new formation of a large MH in 4/33 (12.1%) eyes, failure of MH closure in 10/14 (71.4%) eyes, progression of mean minimum linear diameter (MLD) MH size from baseline 139 (± 67) to 396 (± 130) µm (p < 0.001) and development of a retinal detachment in 4/47 (8.5%) eyes.

CONCLUSION

While PVL leads to a high VMT release rate particularly in pseudophakic eyes, it is associated with a relatively high incidence of MH formation, MH size progression and retinal detachment.

Repeatability and Reproducibility of Macular Hole Size Measurements Using Optical Coherence Tomography

The purpose of this study was to assess the repeatability and reproducibility of measuring the minimum linear diameter (MLD) of macular holes (MHs) using horizontal linear and radial scan modes in optical coherence tomography (OCT). Patients with concurrent sets of radial and horizontal linear OCT volume scans were included. The MLD was measured twice in both scan modes by six raters of three different experience levels (groups). Outcome measures were the reliability and repeatability of MLD measurements. Fifty patients were included. Mean MLD was 317.21(±170.63) µm in horizontal linear and 364.52 (±161.71) µm in radial mode, a difference of 47.31 (±26.48) µm (p < 0.001). In the radial scan mode, MLD was identified within 15° of the horizontal meridian in 27% and within 15° of the vertical meridian in 26.7%, with the remainder (46.3%) in oblique meridians. The intra-group coefficients of repeatability (CR) for horizontal linear mode were 23 µm, 33 µm and 45 µm, and for radial mode 25 µm, 44 µm and 57 µm for groups 1, 2 and 3, respectively. The inter-group CR, taking group 1 as reference standard for groups 2 and 3, were 74 µm and 71 µm for the linear mode, and 62 µm and 78 µm for radial mode. The radial mode provides good repeatability and reliability for measurement of MLD. In a majority of cases the MLD does not lie in the horizontal meridian and would be underestimated using a horizontal OCT mode.

OCRIPLASMIN FOR VITREOMACULAR TRACTION IN CLINICAL PRACTICE: The INJECT Study

PURPOSE

Randomized clinical trials have demonstrated the safety and efficacy of ocriplasmin in patients with vitreomacular traction (VMT), including those with macular hole (MH). The INJECT study prospectively evaluated ocriplasmin in the setting of clinical practice.

METHODS

INJECT was a Phase 4, multicenter, prospective observational study. Patients were followed up for 12 months. Assessments included nonsurgical VMT resolution, nonsurgical MH closure, best-corrected visual acuity, occurrence of vitrectomy, and adverse events.

RESULTS

The efficacy population (N = 395) received an ocriplasmin injection and had optical coherence tomography-confirmed VMT at baseline. At Day 28, the rate of nonsurgical VMT resolution was 40.7% in the overall group, and the rate of nonsurgical MH closure was 36.0% in the VMT with MH group. At Month 12, the rate of ≥2-line best-corrected visual acuity gain (irrespective of vitrectomy) was 36.8% in the overall group and 59.6% in the VMT with MH group. The percentage of patients who underwent vitrectomy in the study eye was 29.1% in the overall group and 55.6% in the VMT with MH group. Photopsia (9.8%) and vitreous floaters (6.8%) were the most frequent adverse events.

CONCLUSION

The INJECT study showed that ocriplasmin is effective in a clinical setting in patients with VMT, with or without MH. No new safety signals were identified from this large and surgeon-selected patient group, although the significant limitations of the study design without an image reading center and scheduled study visit timings should be noted.

Short-Term Results of Ocriplasmin Versus Prompt Vitrectomy for Macular Hole. Which Performs Better?

In this retrospective study, we compared the anatomical and functional changes in patients with vitreomacular traction associated with macular holes between the following groups: (1) Patients who were treated with a single intravitreal injection of ocriplasmin (the OCRIALONE group); (2) those who failed the ocriplasmin treatment and underwent vitrectomy one month later (the OCRIVIT group); and (3) patients who directly underwent par plana vitrectomy (VITREALONE group). A total of 38 patients, 19 in the OCRIALONE group + OCRIVIT group (seven and 12 patients, respectively) and 19 in the VITREALONE group with focal vitreomacular adhesion associated with macular holes were evaluated with spectral domain optical coherence tomography. Functional examinations included best-corrected visual acuity (BCVA) and microperimetry analysis. Visual function changes were compared between the OCRIALONE group + OCRIVIT group and VITREALONE group up to three months. Furthermore, a subgroup analysis compared the OCRIVIT group and the VITREALONE group. BCVA values and the mean retinal sensitivity showed statistically significant improvement in all groups (p < 0.001). Specifically, the retinal sensitivity values at the end of the follow-up were significantly higher in the OCRIALONE group + OCRIVIT group than in the VITREALONE group. These functional findings were also confirmed when the statistical analysis was conducted between the OCRIVIT group and the VITREALONE group. Although the OCRIALONE group + OCRIVIT group exhibited faster retinal thinning than the VITREALONE group (p = 0.006), the analysis of the OCRIVIT group versus the VITREALONE group did not show any statistically significant difference. The better functional results and similar anatomical findings suggest that ocriplasmin can be used as a first-line treatment, and that prompt pars plana vitrectomy as primary surgery does not provide better outcomes in comparison with pars plana vitrectomy after ocriplasmin injection.

Outcomes of Vitrectomy Under Air for Idiopathic Macular Hole

Objectives

To evaluate the outcomes of 23-gauge pars plana vitrectomy (PPV) under air compared with standard PPV for idiopathic macular hole (MH).

Materials and Methods

In this prospective, comparative, interventional case series, 42 eyes of 42 patients with idiopathic MH were enrolled. Twenty-one eyes had vitrectomy with an air-infused technique and 21 eyes underwent vitrectomy with a traditional balanced salt solution-infused technique as a control group. Effective vitrectomy time, total surgery time, microperimetry (MP1), and anatomical and functional results were evaluated.

Results

The mean effective vitrectomy time was significantly lower in the air group than in the control group (7.5±0.3 min and 13.3±0.5 min, respectively, P<0.001). The mean total surgery time was significantly lower in the air group than the control group (21.8±2.0 min and 25.9±1.1 min, respectively, P<0.001). There were no statistically significant changes between preoperative and 3-month postoperative retinal sensitivity values evaluated by MP1 in either group. Anatomical success at 3 months was 100% in both groups. Intraoperative complications noted during the air-infused vitrectomy were retinal touch (10%) and sudden hypotony (10%); in the two pseudophakic eyes, migration of air into the anterior chamber occurred in one (50%) and fogging of the intraocular lens in one eye (50%).

Conclusion

Vitrectomy under air infusion for idiopathic MH showed some advantages over a traditional vitrectomy technique in terms of vitreous visualization, effective vitrectomy time, and total surgery duration, without significantly increasing intraoperative and postoperative complication rates. Postoperative microperimetry results indicated no specific damage to the retina or optic nerve related to the continuous air infusion.

Macular hole morphology and measurement using an automated three-dimensional image segmentation algorithm

Objective

Full-thickness macular holes (MH) are classified principally by size, which is one of the strongest predictors of anatomical and visual success. Using a three-dimensional (3D) automated image processing algorithm, we analysed optical coherence tomography (OCT) images of 104 MH of patients, comparing MH dimensions and morphology with clinician-acquired two-dimensional measurements.

Methods and Analysis

All patients underwent a high-density central horizontal scanning OCT protocol. Two independent clinicians measured the minimum linear diameter (MLD) and maximum base diameter. OCT images were also analysed using an automated 3D segmentation algorithm which produced key parameters including the respective maximum and minimum diameter of the minimum area (MA) of the MH, as well as volume and surface area.

Results

Using the algorithm-derived values, MH were found to have significant asymmetry in all dimensions. The minima of the MA were typically approximately 90° to the horizontal, and differed from their maxima by 55 μm. The minima of the MA differed from the human-measured MLD by a mean of nearly 50 μm, with significant interobserver variability. The resultant differences led to reclassification using the International Vitreomacular Traction Study Group classification in a quarter of the patients (p=0.07).

Conclusion

MH are complex shapes with significant asymmetry in all dimensions. We have shown how 3D automated analysis of MH describes their dimensions more accurately and repeatably than human assessment. This could be used in future studies investigating hole progression and outcome to help guide optimum treatments.

Cost-effectiveness analysis of ocriplasmin versus watchful waiting for treatment of symptomatic vitreomacular adhesion in the US

Aim: Evaluate the cost-effectiveness of ocriplasmin in symptomatic vitreomacular adhesion (VMA) with or without full-thickness macular hole ≤400 μm versus standard of care. Methods: A state-transition model simulated a cohort through disease health states; assignment of utilities to health states reflected the distribution of visual acuity. Efficacy of ocriplasmin was derived from logistic regression models using Ocriplasmin for Treatment for Symptomatic Vitreomacular Adhesion Including Macular Hole trial data. Model inputs were extracted from Phase III trials and published literature. The analysis was conducted from a US Medicare perspective. Results: Lifetime incremental cost-effectiveness ratio was US$4887 per quality-adjusted life year gained in the total population, US$4255 and US$10,167 in VMA subgroups without and with full-thickness macular hole, respectively. Conclusion: Ocriplasmin was cost effective compared with standard of care in symptomatic VMA.

COMPARING INTRAVITREAL AIR AND GAS FOR THE TREATMENT OF VITREOMACULAR TRACTION

PURPOSE

To compare the effect of intravitreal injections of air with gas on vitreomacular traction (VMT) release and attempt to analyze predictive factors for success.

METHODS

The medical records of patients with symptomatic VMT undergoing intravitreal injections (0.3 mL) of either octafluoropropane (C3F8) or air were retrospectively reviewed. The VMT release (primary end point) and the best-corrected visual acuity (secondary end point) were noted 1 month after injection. At baseline and 1 month after the injection, a macular optical coherence tomography was performed.

RESULTS

Twenty-four eyes of 22 patients were included. Vitreomacular traction was released in 10 cases, 7 among 11 C3F8-injected eyes (63%) and 3 among 13 air-injected eyes (23%) (P = 0.045). In eyes with released VMT, ETDRS improved from 61 ± 35 (0-100) to 65 ± 37 (0-100) 1 month after the injection (P = 0.03). All patients with VMT release had a horizontal vitreomacular adhesion of less than 600 µm. Five eyes (23%) underwent vitrectomy after the injection of gas or air.

CONCLUSION

Posterior vitreous detachment in VMT can be observed with both air and gas injection with a low complication rate. The occurrence of VMT release observed with air seemed to be less frequent than that observed with gas.

Pneumatic Vitreolysis for the Treatment of Vitreomacular Traction Syndrome

Objectives:

To evaluate the posterior vitreous release rates after a single injection of expansile gas in patients with vitreomacular traction (VMT) syndrome with or without associated full-thickness macular hole (FTMH).

Materials and Methods:

Thirteen eyes of 12 consecutive patients with VMT (11 eyes) or VMT+FTMH (2 eyes) were reviewed retrospectively. Intravitreal injection of 0.3 mL of pure sulfur hexafluoride (SF6) (9 eyes) or perfluoropropane (C3F8) (4 eyes) was performed. Bobbing the head forward and backward similar to ‘drinking bird’ head movements was instructed until VMT release. Full ophthalmic examination and optical coherence tomography was performed at each visit.

Results:

VMT was released in all patients (100%) and mean release time was 5.2 days (1-19 days). Macular hole closure was not achieved in either of the two eyes with FTMH. Mean central subfield thickness decreased significantly from 361 μm to 263 μm (p=0.007). The mean pretreatment visual acuity was 0.44 LogMAR, which significantly improved to 0.25 LogMAR at the last visit (p=0.003). One of 13 eyes had retinal tear after the procedure which was successfully treated with laser retinopexy. Gas migration to the anterior chamber occurred in one patient. No other complications were observed.

Conclusion:

Pneumatic vitreolysis with C3F8 and SF6 gases is a relatively safe, low-cost, and minimally invasive treatment modality for VMT. However, FTMH closure could not be achieved with pneumatic vitreolysis.

Site-specific PEGylation of micro-plasmin for improved thrombolytic therapy through engineering enhanced resistance against serpin mediated inhibition

The relatively rapid inhibition of microplasmin by α₂-AP leads to short functional half-life of the molecule in vivo, causing inefficient clot dissolution, even after site-specific, local catheter-based delivery. Here, we describe a PEGylation approach for improving the therapeutic potential via improving the survival of microplasmin in presence of its cognate inhibitor, α₂-AP, wherein a series of strategically designed cysteine analogs of micro-plasminogen were prepared and expressed in E. coli, and further modified by covalent grafting in vitro with PEG groups of different molecular sizes so as to select single or double PEG chains that increase the molecular weight and hydrodynamic radii of the conjugates, but with a minimal discernible effect on intrinsic plasmin activity and structural framework, as explored by amidolytic activity and CD-spectroscopy, respectively. Interestingly, some of the purified PEG-coupled proteins after conversion to their corresponding proteolytically active forms were found to exhibit significantly reduced inhibition rates (up to 2-fold) by α₂-AP relative to that observed with wild-type microplasmin. These results indicate an interesting, and not often observed, effect of PEG groups through reduced/altered dynamics between protease and inhibitor, likely through a steric hindrance mechanism. Thus, the present study successfully identifies single- and double-site PEGylated muteins of microplasmin with significantly enhanced functional half-life through enhanced resistance to inactivation by its in vivo plasma inhibitor. Such an increased survival of bioactivity in situ, holds unmistakable potential for therapeutic exploitation, especially in ischemic strokes where a direct, catheter-based deposition within the cranium has been shown to be promising, but is currently limited by the very short in vivo bioactive half-life of the fibrin dissolving agent/s.

Patient-reported outcomes of ocriplasmin for the treatment of vitreomacular traction: a systematic review and synthesis of the literature

Purpose

Vitreomacular traction (VMT) is a disease in which the vitreous exerts abnormally strong traction on the macula, the area of the eye responsible for detailed central vision. If this traction significantly distorts the macula then VMT can lead to troublesome distorted vision (metamorphopsia), sometimes occurring despite relatively preserved visual acuity. Ocriplasmin, administered as a single intravitreal injection, aims to release VMT and improve vision. While the effect of ocriplasmin on traction release and visual acuity is well characterized, the effect of symptoms like metamorphopsia is not.

Methods

A systematic review and synthesis of the literature on patient reported outcomes (PRO) in relation to the use of ocriplasmin for the treatment of VMT was undertaken using MED-LINE and Embase databases, and the Cochrane central register of controlled trials (CENTRAL).

Results

The review identified PRO data from 870 patients across three randomized controlled trials. The most commonly reported PROs were the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25), a broad measure of vision-related quality of life, and Visual Function Response (VFR), an outcome combining quality of life and visual acuity outcomes. Treatment with ocriplasmin produced significant patient benefit vs control (sham or placebo-injection). Ocriplasmin was associated with a higher proportion of patients experiencing a clinically meaningful improvement in visual functioning with a difference of 11.8% for VFQ-25 and 23.2% for VFR responder analyses, respectively.

Conclusion

Patients with VMT have material impairment in visual functioning and quality of life, relative to their reduction in visual acuity. Ocriplasmin results in a significant improvement in visual functioning. Future research could include the development of new PROs specific to VMT.

Long-Term Results of Vitrectomy for Macular Holes after Failure of Vitreolysis

PURPOSE

Ocriplasmin injection may close some small-to-medium macular holes associated with vitreoretinal traction. If the treatment fails, does vitrectomy and gas injection yield the same results as primary surgery?

MATERIAL AND METHODS

We report a retrospective case series study of 3 eyes of 3 consecutive patients operated on a few months after initial intravitreal injection of ocriplasmin and enlargement of the macular hole. The minimal follow-up period after surgery was 18 months.

RESULTS

Surgery was uneventful in all cases. Vitrectomy, internal limiting membrane peeling, and gas injection allowed closing of the 3 macular holes with a progressive improvement in visual acuity over time. Before ocriplasmin injection, visual acuity ranged from 20/60 to 20/32, after failed ocriplasmin injection from 20/80 to 20/40, and at the final follow-up after 18 months from 20/32 to 20/25.

CONCLUSION

Vitrectomy with internal limiting membrane peeling leads to closure of macular holes even in cases of prior failure to close them by ocriplasmin injection.