Transvitreal limited arteriovenous-crossing manipulation without vitrectomy for complicated branch retinal vein occlusion using 25-gauge instrumentation

Improving blood flow in occluded veins to reduce anti-vascular endothelial growth factor injections for branch retinal vein occlusion

Purpose

To assess the relationship between improving blood flow via arteriovenous (AV) sheathotomy without vitrectomy and the total number of anti-vascular endothelial growth factor injections (VEGF) required to treat branch retinal vein occlusion (BRVO).

Methods

In this prospective, clinical case series, 16 eyes of 16 patients at the Toho University Sakura Medical Center with best-corrected visual acuity (BCVA) of 20/40 or worse due to macular edema associated with BRVO were analyzed for 12 months. AV sheathotomy was performed without vitrectomy for all cases. On the second day after surgery, anti-VEGF was injected into the operated eye. During the 12-month follow-up after surgery, pro re nata injections were administered when changes in foveal exudation and BCVA were evident. The blood flow of the occluded vein was assessed before and after AV sheathotomy during the operation using laser speckle flowgraphy. The total number of anti-VEGF injections, central retinal thickness (CRT), and BCVA 12 months after surgery were examined.

Results

The changes in CRT and BCVA from baseline to month 12 were statistically significant (P < 0.01). No additional anti-VEGF injections were required for nine of 16 eyes (56.3%) during the 12 months. The total number of anti-VEGF injections for 12 months correlated with the change rate of blood flow in an occluded vein before and after AV sheathotomy (r = -2.816, P = 0.022).

Conclusions and Importance

Improved blood flow in occluded vein may reduce the need for anti-VEGF injections in BRVO.

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).

Improved perfusion and intraretinal neovascularization after intravitreal bevacizumab injection in central vein occlusion

PURPOSE

To report a case of intraretinal neovascularization in a patient with ischemic central venous occlusion.

METHODS

Case report.

RESULTS

An 18-year-old white man presented with painless decreased vision in the right eye. Slit-lamp and biomicroscopic examinations revealed 360° of neovascularization of the iris, venous tortuosity, severe retinal hemorrhages, cotton wool spots, and massive edema of the macula.

CONCLUSION

This is the first report of observed intraretinal neovascularization after central vein occlusion. Treatment with photocoagulation and intravitreal bevacizumab injection promoted revascularization after 1 year.

Advantages and limitations of small gauge vitrectomy

Small gauge vitrectomy utilizing 23- and 25-gauge instrumentation has definite advantages, but also limitations, due to the physics of smaller instruments and sutureless surgery. Higher infusion and aspiration pressures are needed to remove the vitreous using 23- and 25-gauge probes. The advantages include decreased surgical times, less tissue manipulation, reduced inflammation and pain postoperatively with more rapid visual recovery. A disadvantage is greater instrument flexion than 20-gauge probes, making small gauge vitrectomy more appropriate for indications such as vitreous opacities, epiretinal membranes, macular holes, and simple retinal detachments. There are also some increased complications related to small gauge vitrectomy, including dislocation of cannulas intraoperatively, early postoperative hypotony, choroidal detachment, and possibly an increased risk of infectious endophthalmitis.

25-gauge lens-sparing vitrectomy for stage 4A retinopathy of prematurity

PURPOSE

To evaluate the feasibility of performing lens-sparing vitrectomies using 25-gauge instruments for the management of stage 4A retinal detachments in Retinopathy of Prematurity (ROP).

METHODS

13 eyes of 10 patients with stage 4A retinal detachments underwent a lens-sparing pars plicata vitrectomy. All patients were operated using a three port transconjunctival 25-gauge sutureless technique. The sclerotomies were made 0.5 to 1.0 mm posterior to the limbus through the pars plicata. Core vitrectomy and membrane peeling were performed. A partial fluid-air exchange was used at the end of the procedure in the majority of the cases. The anatomic status of the retina was determined by ophthalmoscopy during routine follow up visits or under general anesthesia. Per-operative complications were recorded.

RESULTS

Eight of the infants were female and two were male. The average postmenstrual age at birth was 26.4 weeks and the average postgestational age at time of surgery was 39.3 weeks (range, 33-44). Three out of the 13 eyes (23%) had zone I ROP. With a mean follow-up of 17 months (range, 4-36) 12 out of the 13 eyes (92%) achieved successful retinal reattachment. One eye developed post operative hypotony with a small choroidal detachment that resolved spontaneously.

CONCLUSIONS

Surgical intervention with a three port 25-gauge transconjunctival sutureless vitrectomy is an effective technique to attach the retina in patients with stage 4A retinal detachment in ROP.

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.

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.

25-Gauge transconjunctival sutureless vitrectomy

PURPOSE OF REVIEW

The history and development of 25-gauge transconjunctival sutureless vitrectomy are reviewed in this paper. The expanded spectrum of appropriate cases and recent innovations in vitrectomy surgery are discussed, as are longer-term outcomes and possible complications.

RECENT FINDINGS

25-Gauge pars plana vitrectomy has evolved significantly since its introduction in 2002, with newer instruments and novel techniques expanding the scope and improving outcomes in vitreoretinal surgery. Proper case selection is imperative, as the smaller scale of the instruments and decreased fluidics work most efficiently when extensive manipulation of intraocular tissue or significant membrane dissection is not required. Unique complications of 25-gauge surgery such as hypotony and a possible increased rate of endophthalmitis may be related to unsutured sclerotomies, and revisions in surgical approach may help to decrease these potentially devastating complications.

SUMMARY

Clinical experience over the last several years has proven that this sutureless system is both safe and efficacious. Decreased surgical times, reduced postoperative inflammation, and more rapid patient recovery have all contributed to an increased acceptance of 25-gauge vitrectomy by retinal physicians.

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.

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.