MANAGEMENT OF MACULAR EDEMA IN BRANCH RETINAL VEIN OCCLUSION WITH SHEATHOTOMY AND RECOMBINANT TISSUE PLASMINOGEN ACTIVATOR

SCORE2 Report 24: Nonlinear Relationship of Retinal Thickness and Visual Acuity in Central Retinal and Hemiretinal Vein Occlusion

PURPOSE

To investigate whether a nonlinear association between central subfield thickness (CST) on spectral-domain OCT and concurrent visual acuity letter score (VALS) exists in eyes treated initially with aflibercept or bevacizumab for macular edema associated with central retinal vein occlusion (CRVO) or hemiretinal vein occlusion (HRVO) in the Study of Comparative Treatments for Retinal Vein Occlusion 2 (SCORE2).

DESIGN

Long-term follow-up after a randomized clinical trial from 64 centers in the United States.

PARTICIPANTS

Participants were followed up to 60 months and treated at investigator discretion after completing the 12-month treatment protocol.

METHODS

Two-segment linear regression models were compared with simple linear regression models of VALS on CST. Pearson correlation coefficients were calculated to assess strength of CST and VALS associations.

MAIN OUTCOME MEASURES

Central subfield thickness was measured by OCT and VALS by the electronic Early Treatment Diabetic Retinopathy Study methodology.

RESULTS

Estimated inflection points, reflecting turning points at which the CST and VALS association changes from positive to negative, calculated at 7 postbaseline visits, range from 217 to 256 μm. A strongly positive correlation exists to the left of each estimated inflection point, ranging from 0.29 (P < 0.01 at month 60) to 0.50 (P < 0.01 at month 12), and a strongly negative correlation exists to the right of each estimated inflection point, ranging from -0.43 (P < 0.01 at month 1) to -0.74 (P < 0.01 at month 24). Randomization statistical tests showed that 2-segment models are favored over 1-segment models for all postbaseline months (P < 0.001 for all tests performed).

CONCLUSIONS

The relationship between CST and VALS in eyes with CRVO or HRVO after treatment with anti-vascular endothelial growth factor (VEGF) therapy is not simply linear. The usually modest correlations between OCT-measured CST and visual acuity belie strong left and right correlations present in 2-segment models. Post-treatment CST close to the estimated inflection points showed the best expected VALS. The SCORE2 participants with a post-treatment CST after treatment close to the estimated inflection points of 217 to 256 μm showed the best VALS. In patients treated with anti-VEGF for macular edema associated with CRVO or HRVO, a thinner retina is not always associated with better VALS.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

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.

Five-year outcomes of pars plana vitrectomy for macular edema associated with branch retinal vein occlusion

Purpose

Long-term outcomes of pars plana vitrectomy (PPV) for macular edema (ME) associated with branch retinal vein occlusion (BRVO) have been previously reported, but the studies did not report the number of additional treatments after surgery. During 5 years of follow-up, we therefore investigated the efficacy and safety of PPV for BRVO and evaluated the incidence of additional treatments.

Methods

We retrospectively reviewed the medical records of 25 eyes of 24 patients who underwent PPV for ME associated with BRVO and were followed up for at least 5 years. Best-corrected visual acuity was measured, and foveal thickness was assessed by optical coherence tomography. Additional treatments were also investigated.

Results

The logarithm of the minimal angle of resolution (logMAR) improved from 0.53±0.23 at baseline to 0.16±0.25 at 5 years (P<0.0001). The foveal thickness decreased from 535±222 µm at baseline to 205±143 µm at 5 years (P<0.0001). For the eyes with residual ME, the following additional treatments were performed within 5 years of follow-up: sub-Tenon injection of triamcinolone acetonide in two eyes, intravitreal injection of bevacizumab in three eyes, grid laser photocoagulation in one eye, and direct photocoagulation of macroaneurysm in one eye. Additional surgeries were performed in two eyes: for one eye, phacoemulsification extraction of the ocular lens and intraocular lens implantation were performed because of cataract progression, and for the other eye, additional PPV was done for postoperative retinal detachment.

Conclusion

PPV was effective for resolution of ME associated with BRVO and improved visual acuity with a small number of additional treatments during long-term follow-up.

Release of experimental retinal vein occlusions by direct intraluminal injection of ocriplasmin

PURPOSE

Retinal vein occlusions (RVO) are a major cause of vision loss in people aged 50 years and older. Current therapeutic options limit the consequences of RVO but do not eliminate the cause. Cannulation of the involved vessel and removal of the clot may provide a more permanent solution with a less demanding follow-up. However, cannulation of smaller retinal veins remains challenging. This paper explores the use of ocriplasmin (recombinant plasmin without its kringles) to clear RVO, using a robotic micromanipulator.

METHODS

Branch RVO were induced in a porcine model with rose bengal followed by 532 nm endolaser to the superior venous branch of the optic nerve. The vein was cannulated proximal to the occlusion or beyond the first branching vessel from the obstruction. The vein was infused with a physiologic citric acid buffer solution (CAM) or CAM/ocriplasmin. The time of cannulation, number of attempts, and the ability to release the thrombus were recorded.

RESULTS

Cannulation and infusion was possible in all the cases. The use of a micromanipulator allowed for a consistent cannulation of the retinal vein and positional stability allowed the vein to remain cannulated for up to 20 min. In none of the attempts (5/5) with CAM did the thrombus dissolve, despite repeat infusion/relaxation cycles. In 7/7 injections of CAM/ocriplasmin near to the point of obstruction, the clot started to dissolve within a few minutes of injection. An infusion, attempted beyond the first venous branch point proximal to the clot, was unsuccessful in 2/3 attempts.

CONCLUSIONS

Ocriplasmin is effective in resolving RVO if injected close to the site of occlusion with the use of a micromanipulator.

Matched control study of visual outcomes after arteriovenous sheathotomy for branch retinal vein occlusion

Background

The purpose of this study was to evaluate visual outcomes of arteriovenous sheathotomy for macular edema due to branch retinal vein occlusion (BRVO).

Methods

The medical records of 45 eyes from 45 patients who had undergone vitrectomy surgery with arteriovenous sheathotomy for BRVO were studied. Forty-five eyes of 45 patients with a BRVO but without intervention were studied as the control group. The best-corrected visual acuity and central macular thickness were compared between the two groups at baseline and at 1, 3, 6, and 12 months postoperatively.

Results

Improvement of best-corrected visual acuity was 0.42 logarithm of the minimum angle of resolution (logMAR) units in the sheathotomy group and 0.22 logMAR units in the control group (P=0.007). The mean postoperative central macular thickness was significantly thinner in the sheathotomy group at 1 month (P=0.01), but not at 3, 6, and 12 months (P=0.75, P=0.81, and P=0.46, respectively). Improvement of best-corrected visual acuity at 12 months was significantly correlated with baseline best-corrected visual acuity, age, duration of symptoms, and sheathotomy (P<0.05).

Conclusion

Arteriovenous sheathotomy for BRVO improves best-corrected visual acuity significantly more than the natural course of the BRVO disease process.

Branch retinal vein occlusion: treatment modalities: an update of the literature

BACKGROUND

Retinal vein occlusion is the second most common retinal vascular disorder after diabetic retinopathy and is considered to be an important cause of visual loss. In this review, our purpose is to update the literature about the treatment alternatives for branch retinal vein occlusion.

METHODS

Eligible papers were identified by a comprehensive literature search of PubMed, using the terms "branch retinal vein occlusion," "therapy," "intervention," "treatment," "vitrectomy," "sheathotomy," "laser," "anti-VEGF," "pegaptanib," "bevacizumab," "ranibizumab," "triamcinolone," "dexamethasone," "corticosteroids," "non-steroids," "diclofenac," "hemodilution," "fibrinolysis," "tPA," and "BRVO." Additional papers were also selected from reference lists of papers identified by the electronic database search.

RESULTS

Treatment modalities were analyzed.

CONCLUSIONS

There are several treatment modalities for branch retinal vein occlusion and specifically for its complications, such as macular edema, vitreous hemorrhage, retinal neovascularization, and retinal detachment, including anti-aggregative therapy and fibrinolysis, isovolemic hemodilution, vitrectomy with or without sheathotomy, peripheral scatter and macular grid retinal laser therapy, non-steroid agents, intravitreal steroids, and intravitreal anti-vascular endothelial growth factors (anti-VEGFs).

Combined intravitreal bevacizumab and grid laser photocoagulation for macular edema secondary to branch retinal vein occlusion

PURPOSE

To evaluate long-term efficacy of intravitreal bevacizumab (IVB) versus combined IVB and macular grid laser photocoagulation for the treatment of macular edema secondary to branch retinal vein occlusion (BRVO).

METHODS

In this prospective study, 18 eyes were randomized into 2 groups according to treatment: Group 1 (9 eyes) underwent IVB at baseline, at month 1, and at month 2; Group 2 (9 eyes) underwent same IVB protocol combined with macular grid laser photocoagulation. Macular edema and visual acuity represented the endpoints of the study. IVB reinjections were performed in both groups if recurrent macular edema was diagnosed. Spectral domain optical coherence tomography examination as well as visual acuity examination were performed during follow-up. Statistical evaluation was performed for a matched-pair analysis.

RESULTS

In Group 1, median baseline central retinal thickness (CRT) decreased from 420 µm (95% confidence interval 355.6-484.4) to 323 µm (261.44-384.56) at month 12 (p=0.06); median baseline BCVA improved from 0.7 logMAR (0.54-0.86) to 0.4 logMAR (0.29-0.51) at month 12 (p<0.01). In Group 2, baseline CRT decreased from 386 µm (353.91-418.09) to 238 µm (200.58-275.42) at month 12 (p<0.01); median BCVA improved from 0.6 logMAR (0.45-0.75) to 0.2 logMAR (0.12-0.28) at month 12 (p<0.01). A statistically significant difference (p=0.03) was found regarding the median number of injections (Group 1: 4±1.1; Group 2: 3±0.4).

CONCLUSIONS

Both treatment modalities appeared effective to control BRVO-induced macular edema. In the combined-treatment Group, we observed a lower number of reinjections during follow-up, suggesting the efficacy of grid laser photocoagulation to reduce the number of intravitreal injections and maintain short- and long-term results of the therapy.

Feasibility study on retinal vascular bypass surgery in isolated arterially perfused caprine eye model

PURPOSE

To investigate the feasibility of bypassing occluded segments of retinal venous main vessels in isolated, arterially perfused caprine eyes via the closed-sky vitrectomy approach using keratoprosthesis.

METHODS

Isolated caprine eyes were used in this study. For each eye, the retinal vessel was perfused by Krebs solution via ophthalmic artery, and pars plana vitrectomy was performed using temporary keratoprosthesis. All retinal micro-vascular maneuvers were performed in a closed-sky eyeball. The main retinal vein was blocked by endodiathermy at the site of the vessel's first branching. Two openings, several millimeters apart, were created by vascular punctures in both the main vein and its branch vein wall straddling the induced occluded segment. Catheterization was achieved using a flexible polyimide tube, with each end inserted into the vessel wall opening. A sealed connection between the vessel and the tube was obtained by endodiathermy. Bypass of the occluded retinal vein segment was thus achieved, and the patency of this vascular bypass was confirmed by intravascular staining.

RESULTS

Puncturing, catheterization, and endodiathermy were viable by closed-sky approach using keratoprosthesis. Bypassing of the occluded retinal main vein segment was accomplished with the combination of these maneuvers. Good results were obtained in 23 of 38 (60%) caprine eyes.

CONCLUSIONS

This study demonstrated that bypassing the occluded segment of retinal main vein can be successfully performed in a closed-sky eyeball model of isolated, arterially perfused caprine eye. This early work indicated that the more advanced retinal vascular bypass surgery in in vivo eye may be feasible in the future.

Management of retinal vein occlusion--consensus document

Retinal vein occlusion (RVO) can have severe consequences for the people affected by the disease, including visual loss with costly social repercussions. Currently, there is no European consensus with regard to the management of RVO. Following a careful review of the medical literature as well as the data from several clinical trials, a collaborative group of retina specialists put forth practical recommendations based on the best available scientific evidence for the clinical approach to RVO. Taking into consideration the recent advances in diagnostic tools and management options, the present document aims to provide the European ophthalmologists with guidelines for clinical practice to the benefit of their patients.

Long-term study of vascular perfusion effects following arteriovenous sheathotomy for branch retinal vein occlusion

PURPOSE

To evaluate the perfusion effects and long-term visual outcome of pars plana vitrectomy (PPV) combined with arteriovenous sheathotomy (AVS) with or without triamcinolone for nonischaemic branch retinal vein occlusion (NI-BRVO).

METHODS

Prospective, interventional case series of eight patients with NI-BRVO and haemorrhagic macular oedema. Patients underwent PPV and AVS (n = 5), or PPV, AVS and intravitreal triamcinolone (IVT, n = 3). A masked grading technique assessed fundus photographs and fluorescein angiography (FFA) following surgery. Scanning laser ophthalmoscopy/optical coherence tomography (SLO/OCT) evaluated macular oedema and outer retinal architecture. Main outcomes examined included visual acuity (VA), retinal reperfusion, collateral vessel regression, vascular dilatation, cystoid macular oedema (CMO), and ocular neovascularization.

RESULTS

Seven of eight patients underwent uncomplicated surgery, with increased intraretinal perfusion and reduced engorgement of distal retinal veins. The mean pre-logMAR VA was 0.8 (SD 0.17) and did not improve significantly after surgery (post-logMAR 0.6, SD 0.38; p = 0.11, paired t-test). SLO/OCT showed persistent CMO in four patients, and subfoveal thinning of the photoreceptor layer. Collateral vessels disappeared at the blockage site post-AVS in 7/8 eyes, and this was associated with improved retinal perfusion. Six of eight patients developed epiretinal membrane. No patients developed ocular neovascularization. The average follow-up was 34.5 months.

CONCLUSIONS

PPV with AVS is a safe procedure, and adjunctive IVT had no additional effects on vascular perfusion. Successful decompressive surgery was followed by disappearance of collateral vessels at the BRVO blockage site and was a clinical marker for intravascular reperfusion. Long-term epiretinal gliosis and subfoveal photoreceptor atrophy limited functional and visual recovery.

SCORE Study report 1: baseline associations between central retinal thickness and visual acuity in patients with retinal vein occlusion

OBJECTIVE

To investigate the relationship between baseline center point retinal thickness measured by optical coherence tomography (OCT) and best-corrected visual acuity in eyes with macular edema associated with retinal vein occlusion and to investigate other factors associated with baseline visual acuity letter score.

DESIGN

The Standard Care versus COrticosteroid for REtinal Vein Occlusion (SCORE) Study includes 2 multicenter, randomized clinical trials: one evaluating participants with central retinal vein occlusion (CRVO) and the other evaluating participants with branch retinal vein occlusion (BRVO).

PARTICIPANTS

After omitting 17 participants with missing or unreliable OCT measurements, analyses proceeded with 665 enrolled SCORE Study participants (665 eyes), including 262 with CRVO and 403 with BRVO.

METHODS

At baseline, center point thickness was measured by OCT (Stratus OCT 3 [n=663] and OCT2 [n=2]; Carl Zeiss Meditech, Dublin, CA), and visual acuity was measured by the electronic Early Treatment Diabetic Retinopathy Study (E-ETDRS) methodology.

MAIN OUTCOME MEASURES

Center point thickness and best-corrected E-ETDRS visual acuity letter score.

RESULTS

The correlation coefficient for the association between baseline OCT-measured center point thickness and best-corrected E-ETDRS visual acuity letter score is -0.27 (95% confidence limit: -0.38 to -0.16) for participants in the CRVO trial and -0.28 (95% confidence limit: -0.37 to -0.19) in the BRVO trial. Regression modeling estimated the following decrease in baseline visual acuity letter score for every 100-microm increase in OCT-measured center point thickness: 1.7 letters (P=0.0007) for CRVO and 1.9 letters (P<0.0001) for BRVO. On the basis of multivariate regression models, baseline factors significantly associated (P<0.05, after adjusting for multiple testing) with baseline visual acuity letter score include age and duration of macular edema for CRVO participants and center point thickness and presence of cystoid spaces for BRVO participants.

CONCLUSIONS

The correlation between OCT-measured center point thickness and visual acuity letter score is modest. OCT-measured center point thickness represents a useful tool for the detection and monitoring of macular edema in retinal vein occlusion, but it cannot reliably substitute for visual acuity measurements.

Post-vitrectomy tissue plasminogen activator injection for central retinal vein occlusion

Three patients with recent central retinal vein occlusion underwent vitrectomy, fluid-air exchange, and a 50-microg tissue plasminogen activator intravitreal injection. After a mean follow-up period of 38.7 weeks, no patient's vision improved and one patient required an additional vitrectomy. Post-vitrectomy tissue plasminogen activator injection did not improve the course of central retinal vein occlusion in these three cases.

Long-term visual outcome of arteriovenous adventitial sheathotomy on branch retinal vein occlusion induced macular edema

Purpose

To evaluate long-term visual outcome of arteriovenous adventitial sheathotomy in BRVO-induced macular edema.

Methods

The visual outcomes of 8 patients following vitrectomy with arteriovenous adventitial sheathotomy for BVO-induced macular edema (surgery group) were retrospectively evaluated. The three year post-operative visual acuity of the surgery group was compared with that of the conservatively managed controls.

Results

All patients were followed for a minimum of 36 months. Mean BCVA (logMAR) in the surgery group changed from 1.10± 0.34 to 1.19±0.70 and to 0.80±0.36 at 12 and 36 months, respectively (p=0.959 at 12 months, p=0.018 at 36 months). In the control group, visual acuity improved from 1.15±0.43 to 0.43±0.44 and to 0.43±0.39 at 12 and 36 months, respectively (p=0.015 at 12 months, at p=0.003 at 36 months). A strong trend toward better visual acuity at 12 months and final examination was observed for controls. (surgery vs. control group, p=0.052 at 12 months, p=0.066 at 36 months).

Conclusions

Considering the favorable natural course of BVO and the unproven effect of reperfusion on macular edema, surgical efficacy of arteriovenous adventitial sheathotomy requires further evaluation.

Visual acuity and multifocal electroretinographic changes after arteriovenous crossing sheathotomy for macular edema associated with branch retinal vein occlusion

PURPOSE

To evaluate the influence of arteriovenous (AV) sheathotomy on retinal function with central multifocal electroretinography (mfERG) in eyes with macular edema secondary to branch retinal vein occlusion (BRVO).

METHODS

Fifteen patients (15 eyes) who underwent AV sheathotomy for macular edema secondary to BRVO were included in the study. Best-corrected visual acuity and mfERG responses from the most central seven hexagons were analyzed before and 6 months after the operation.

RESULTS

The mean preoperative Early Treatment Diabetic Retinopathy Study (ETDRS) score +/- SD was 34.1 +/- 12.7 letters (Snellen equivalent, 20/50) and significantly improved up to 40.5 +/- 10.9 letters (Snellen equivalent, 20/40) at 6 months after AV sheathotomy (P = 0.027, Wilcoxon signed rank test). The mean preoperative P1 amplitude +/- SD of the most central 7 hexagons was 39.30 +/- 10.86 nV/deg(2) for the affected eye versus 47.72 +/- 6.67 nV/deg(2) for the normal fellow (control) eye (P = 0.013, Mann-Whitney U test) and significantly increased up to 50.71 +/- 15.58 nV/deg at 6 months after the operation (P = 0.014, Wilcoxon signed rank test). Significant correlations between preoperative and postoperative ETDRS score and preoperative P1 amplitude were present (r = 0.929, P < 0.001; r = 0.768, P = 0.001; respectively [Spearman correlation]).

CONCLUSIONS

AV sheathotomy improved macular function and anatomical outcome as measured by ETDRS score and mfERG responses in patients with macular edema due to BRVO.

Arteriovenous crossing sheathotomy versus intravitreal triamcinolone acetonide injection for treatment of macular edema associated with branch retinal vein occlusion

PURPOSE

To compare the functional and anatomical outcomes of arteriovenous (AV) sheathotomy and intravitreal triamcinolone acetonide (IVTA) injection in the treatment of macular edema associated with branch retinal vein occlusion (BRVO).

METHODS

Forty eyes of 40 patients with macular edema secondary to BRVO were randomized into two treatment groups. A total of 20 patients received AV sheathotomy (sheathotomy group), and the second group of 20 patients was treated with IVTA (IVTA group). Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA) score, total macular volume measured, and foveal thickness by 3rd generation optical coherence tomography (OCT3) were evaluated as main outcome measurements.

RESULTS

The average changes in ETDRS scores, total macular volumes, and foveal thicknesses compared to baseline values, were significant 3 months and 6 months after treatment in both groups (P < 0.05, paired t-test), but only the IVTA group showed significant improvements 1 month after treatment. The between-group differences in average ETDRS score, total macular volume, and foveal thickness changes were significantly better at 1 month after treatment in the ITVA group (P = 0.026, P < 0.001, P = 0.001, respectively, Student's t-test), at which time IVTA patients had better vision and anatomical outcomes than did those in the sheathotomy group.

CONCLUSIONS

After either AV sheathotomy or IVTA treatment, patients with macular edema secondary to BRVO showed similar functional and anatomical outcomes 6 months later. When the cost and the risks of vitreoretinal surgery are considered, IVTA treatment may be a better treatment option, as the drug yields better short-term outcomes.

Sheathotomy in complicated cases of branch retinal vein occlusion

PURPOSE

To report the clinical experience and results of using a microsurgical technique to decompress the arteriovenous connection in complicated branch retinal vein occlusion (BRVO) combined with haemorrhage, oedema and ischaemia.

METHODS

We carried out a retrospective, non-randomized, interventional case study of the surgical sheathotomy decompression procedure. We enrolled 12 patients (seven women, five men; median age 64 years) with BRVO and decreased visual acuity (VA) caused by haemorrhage, oedema and ischaemia. The mean duration of thrombosis was 7 months (2-15 months). The patients were examined for pre- and postoperative best corrected VA (BCVA), intraocular pressure (IOP) and fundus photography. Ten patients were examined with fluorescein angiography and eight with ocular coherence tomography (OCT). Postoperative progression of cataract was recorded, as were other complications. The mean follow-up time was 20 months (8-39 months).

RESULTS

Best corrected VA had improved in nine patients, was unchanged in one patient and had deteriorated in two patients at the last follow-up. Noted complications were venous haemorrhage at surgery in five patients, retinal detachment in one patient and progression of cataract in four patients.

CONCLUSIONS

Microsurgical treatment with sheathotomy of BRVO is a technically feasible procedure with few complications. Postoperative increased reperfusion could explain the resolution of macular haemorrhage, oedema and ischaemia, and may improve visual function in patients with this common vascular eye disease.

Branch retinal vein occlusion: pathogenesis, visual prognosis, and treatment modalities

In branch retinal vein occlusion (BRVO), abnormal arteriovenous crossing with vein compression, degenerative changes of the vessel wall and abnormal hematological factors constitute the primary mechanism of vessel occlusion. In general, BRVO has a good prognosis: 50-60% of eyes are reported to have a final visual acuity (VA) of 20/40 or better even without treatment. One important prognostic factor for final VA appears to be the initial VA. Grid laser photocoagulation is an established treatment for macular edema in a particular group of patients with BRVO, while promising results for this condition are shown by intravitreal application of steroids or new vascular endothelial growth factor inhibitors. Vitrectomy with or without arteriovenous sheathotomy combined with removal of the internal limiting membrane may improve vision in eyes with macular edema which are unresponsive to or ineligible for laser treatment.

The role of vitrectomy assisted rt-PA injection for the management of branch retinal vein occlusion: case report

Case reports on three patients who underwent vitrectomy assisted t-PA injection for the management of branch retinal vein occlusion. Three-port, 20-gauge vitrectomy was performed under local anesthesia. After posterior vitreous detachment and fluid-air exchange, 50 microg t-PA/0.5 ml were injected in the eye. All patients were instructed for strict supine position for 6 hours. Main outcome measure was visual acuity. Three patients with branch vein occlusion (BVO) were studied, with duration of symptoms less than 25 days, and mean follow-up period of 18.8 months. Although no intraoperative complications were noticed, no one showed any significant improvement of vision. One patient required a second operation for the management of intravitreal hemorrhage, and another developed an epiretinal membrane. Vitrectomy assisted t-PA injection does not seem to improve the course of branch retinal vein occlusion in this small case series. Future research on intravitreal thrombolysis needs to be focused on additional mechanical approaches and modalities that can facilitate the access of the drug into the vascular lumen.

Laser Scanning Imaging for Macular Disease

OBJECTIVE

To evaluate currently available data in the published literature to answer the question of whether laser scanning imaging is a sensitive and specific tool for detecting macular disease when compared with the current standard technique of slit-lamp biomicroscopy or stereoscopic fundus photography.

METHODS

Literature searches conducted in December 2004 and in August 2006 retrieved 370 citations. The Retina Panel members selected 65 articles for the panel methodologist to review and rate according to the strength of the evidence. Of the 65 articles reviewed, 6 provided level I evidence, 9 provided level II evidence, and 50 provided level III evidence. A level I rating was assigned to studies that reported an independent masked comparison of an appropriate spectrum of consecutive patients, all of whom had undergone both the diagnostic test and the reference standard. A level II rating was assigned to an independent masked or objective comparison; a study performed in a set of nonconsecutive patients or confined to a narrow spectrum of study individuals (or both), all of whom had undergone both the diagnostic test and the reference standard; or an independent masked comparison of an appropriate spectrum, but the reference standard had not been applied to all study patients. A level III rating was assigned when the reference standard was unobjective, unmasked, or not independent; positive and negative tests were verified using separate reference standards; or the study was performed in an inappropriate spectrum of patients.

RESULTS

There are high-level studies of the use of laser scanning imaging to quantify macular thickness and, thereby, macular edema in patients with diabetic retinopathy and to examine patients with a macular hole. There is lower-quality evidence on the use of laser scanning imaging for other diseases of the macula. There is insufficient evidence to compare the different instruments.

CONCLUSIONS

There is level I evidence that laser scanning imaging can accurately and reliably quantify macular thickness in patients with diabetic retinopathy. There is level I evidence that optical coherence tomography provides additional information to clinical examination when used in patients with a macular hole. Laser scanning imaging provides important information that is helpful in patient management by allowing objective serial quantitative measurements. Although further studies are needed to develop an optimal testing strategy using these imaging modalities, laser scanning imaging is a sensitive, specific, reproducible tool for diagnosing macular edema and, therefore, is likely to be useful for managing diseases that result in macular edema.

Arteriovenous sheathotomy for persistent macular edema in branch retinal vein occlusion

Purpose

To evaluate the efficacy of arteriovenous (AV) sheathotomy with internal limiting membrane peeling for persistent or recurrent macular edema after intravitreal triamcinolone injection and/or laser photocoagulation in branch retinal vein occlusion.

Methods

Twenty-two eyes with branch retinal vein occlusion (BRVO) with recurrent macular edema underwent vitrectomy with AV sheathotomy and internal limiting membrane peeling. All eyes had previous intravitreal triamcinolone injection and/or laser photocoagulation for macular edema. The best corrected visual acuity (BCVA), fluorescein angiography and optical coherence tomography (OCT) before and after surgery were compared.

Results

The mean preoperative BCVA (log MAR) were 0.79±0.29 and postoperative BCVA (log MAR) at 3 months was 0.57±0.33. And improvement of visual acuity ≥2 lines was observed in 10 eyes (45%). The mean preoperative fovea thickness measured by OCT was 595.22±76.83 µm (510-737 µm) and postoperative fovea thickness was 217.60±47.33 µm (164-285 µm).

Conclusions

Vitrectomy with AV sheathotomy can be one treatment option for the patients with recurrent macular edema in BRVO.

Long-term outcomes of vitrectomy with or without arteriovenous sheathotomy in branch retinal vein occlusion

PURPOSE

To evaluate the long-term effect of vitrectomy with or without arteriovenous sheathotomy for macular edema secondary to branch retinal vein occlusion (BRVO).

METHODS

The study was a prospective, randomized, comparative, interventional case series of 36 patients (36 eyes) who underwent pars plana vitrectomy with or without arteriovenous sheathotomy for macular edema due to BRVO of <or=8 weeks' duration of symptoms. Eighteen eyes with arteriovenous sheathotomy (sheathotomy group) were compared with 18 eyes without sheathotomy (vitrectomy group). Main outcomes measures were best-corrected visual acuity and central foveal thickness as evaluated by optical coherence tomography.

RESULTS

Baseline demographic characteristics of the groups were similar. Postoperative follow-up period ranged from 12 months to 45 months (31 months). Median best-corrected visual acuity significantly improved from 0.4 at baseline to 1.0 at the final visit in both groups, and there was no significant difference in best-corrected visual acuity at any postoperative period between the groups. Of 16 patients with duration of symptoms of <4 weeks, those with arteriovenous sheathotomy had a tendency toward better visual outcomes than those without arteriovenous sheathotomy (P = 0.064). The central foveal thickness also significantly decreased after surgery in both groups, but the differences were not significant for the two groups at each time point. No patients had severe intraoperative and/or postoperative complications.

CONCLUSIONS

Our findings suggest that vitrectomy with or without arteriovenous sheathotomy may improve the long-term functional and tomographic outcomes for patients with macular edema secondary to BRVO. Although additional arteriovenous sheathotomy did not lead to a distinct functional benefit in this series, early surgical intervention may result in better visual outcomes.

Arteriovenous adventitial sheathotomy for branch retinal vein occlusion: report of a case with longterm follow-up

PURPOSE

To report the longterm follow-up of a case of branch retinal vein occlusion (BRVO) treated with vitrectomy and adventitial sheathotomy.

METHODS

A three-port vitrectomy was performed in a 55-year-old man with symptoms of BRVO of about 3 months' duration. After a core vitrectomy, the adventitial sheath of the affected arteriovenous crossing was dissected so that the anterior surface of the arteriole was freely exposed.

RESULTS

On the second postoperative day, visual acuity (VA) in the affected left eye had increased from preoperative 0.3 to 0.6. Within 6 months the fundus had almost normalized and vision improved to 1.0. Cataract surgery was performed about 2 years after the vitrectomy. At a follow-up 4 years and 11 months after the sheathotomy, VA was 1.0 and no signs of recurrence were seen.

CONCLUSIONS

Adventitial sheathotomy may improve vision in selected cases of BRVO. Further studies are necessary to determine the role of sheathotomy in the management of cases with BRVO.

Evaluation of arteriovenous crossing sheathotomy for decompression of branch retinal vein occlusion

PURPOSE

To report the effects of arteriovenous adventitial sheathotomy on anatomical and functional improvements in patients with macular oedema due to branch retinal vein occlusion (BRVO).

METHODS

Pars plana vitrectomy and arteriovenous sheathotomy was performed on 11 patients with BRVO who had vision loss due to macular oedema. Ten patients with macular oedema due to BRVO and who have been treated with grid laser photocoagulation were included in the control group. The measurement of visual acuity with ETDRS chart was taken preoperatively and at 1, 3, 6, and 9 months follow-up in the study group and at 1, 3, 6, and 9 months after grid laser in the control group.

RESULTS

The mean preoperative logMAR visual acuity was 0.84+/-0.3 in the surgical group and 1.06+/-0.4 in the control group. The postoperative mean logMAR visual acuity was 0.41+/-0.2, 0.40+/-0.2, 0.40+/-0.3, and 0.36+/-0.3 at 1, 3, 6, and 9 months follow-up, respectively. In the control group the postlaser mean logMAR visual acuity was 0.92+/-0.3, 0.87+/-0.4, 0.85+/-0.3, and 0.82+/-0.3 at 1, 3, 6, and 9 months follow-up, respectively. The improvements of visual acuity in both groups were statistically significant when compared to pretreatment (P=0.003 and P=0.007 at 9 months in the study and control group, respectively).

CONCLUSION

Arteriovenous sheathotomy for decompression of BRVO in patients who have vision loss due to macular oedema was safe and effective for anatomical and functional improvement and resulted in significantly better visual outcomes than a matched control group of laser-treated eyes.

Bevacizumab zur Therapie des sekundären Makulaödems nach venösen Gefäßverschlüssen

Application of VEGF inhibitors represents a treatment option for macular edema secondary to retinal vein occlusion that targets the disease at the causal molecular level. First reports on intravitreal injections of bevacizumab show promising morphological and functional effects and demonstrate that bevacizumab is a potent antiedematous agent in this context. A significant reduction of the central retinal thickness followed by a rapid improvement of visual acuity may be achieved within days. In a pilot study with a review period of 3 months, we found a significant improvement of one or more lines in 93% and four or more lines in 27% of eyes. This was associated with a concomitant significant reduction in central retinal thickness, which, however, was not sustained by a single injection (64% reduction after 1 month and 28% after 3 months). No relevant adverse events were noted. The duration of action after intravitreal bevacizumab administration is currently unknown. Reinjections will be necessary to maintain a lasting beneficial effect. Prospective, controlled long-term studies are mandatory to develop standardized treatment protocols that allow a safe and effective application of this off-label therapy.

The management of retinal vein occlusion: is interventional ophthalmology the way forward?

Retinal vein occlusions (RVO) are the second commonest sight threatening vascular disorder. Despite its frequency treatments for RVO are unsatisfactory and include several that have not been tested by large, well designed, prospective, randomised controlled trials. There is also the lack of long term follow up in many of the available small uncontrolled studies, and the timings of interventions are haphazard. This review aims to evaluate the current knowledge relating to the pathogenesis, suggested treatments for the different types of RVO, and their complications. Isovolaemic haemodilution is of limited benefit and should be avoided in patients with concurrent cardiovascular, renal, or pulmonary morbidity. Evidence to date does not support any therapeutic benefit from radial optic neurotomy, optic nerve decompression, or arteriovenous crossing sheathotomy on its own. Vitrectomy combined with intravenous thrombolysis may offer promise for central RVO. Similarly, vitrectomy combined with arteriovenous sheathotomy intravenous tissue plasminogen activator may offer benefits for branch RVO. RVOs occur at significantly high frequency to allow future prospective randomised controlled studies to be conducted to evaluate the role of different therapeutic modalities singly or in combination.