Trypan blue staining in vitreoretinal surgery

PURPOSE: To evaluate the efficacy of trypan blue for staining the internal limiting membrane (ILM) and epiretinal membranes (ERM) in vitreoretinal surgery. DESIGN: Prospective noncomparative case series. PARTICIPANTS: Fifty eyes of 50 patients with macular pucker (n = 22), macular hole (n = 18), or a combination (n = 2), proliferative vitreoretinopathy (n = 5), or diabetic retinopathy (n = 3). METHODS: Trypan blue 0.2% was used to stain the ILM or ERM during vitreoretinal surgery. MAIN OUTCOME MEASURES: The intraoperative visibility of the membranes was scored as poor, moderate, good, or excellent. RESULTS: The application of trypan blue onto the ILM or the ERM resulted in a useful bluish staining, facilitating the identification, delineation, and removal of the membranes in all surgeries. No residual staining or adverse effects related to the dye were observed. CONCLUSIONS: Trypan blue stains both ILM and ERM and might be an useful tool in vitreoretinal surgery.     

Role of trypan blue in epiretinal membrane surgery

INTRODUCTION: Idiopathic epiretinal membrane (ERM) results from detachment of the posterior hyaloid. Vitrectomy and peeling are the treatment of choice. Trypan blue 0.15% (TB) stains the epiretinal membrane and the internal limiting membrane (ILM), facilitating surgery and thus allowing selective and complete removal with less retinal damage. We conducted a study evaluating the advantages of selective staining associated with surgery, the incidence of postoperative damage, and the influence on final visual acuity. MATERIAL AND METHODS: Fourteen patients were operated on by the same surgeon, who carried out a complete vitrectomy, then fluid-air exchange for dye injection of undiluted 0.2 ml of Trypan blue 0.15% in front of the membrane, which was then easily distinguished from the area under the retina. Preoperative visual acuity, postoperative damage, as well as eye status at the end of follow-up are discussed. Transmission electron microscopy was used to determine if epiretinal membrane removal was complete and selective. Angiography was systematically used to study the state of retina before and after surgery. RESULTS: Preliminary results show that trypan blue is useful and facilitates complete removal of ERM and ILM. It may reduce long-term complications and recurrent membrane formation. Trypan blue is a staining agent that is quick and easy to use. It presents no short-term toxic effects. Functional results in 6 months show improvement of visual acuity and disappearance of metamorphopsia. CONCLUSION: Idiopathic epiretinal membrane surgery with tryptan blue staining is a better alternative than indocyanine green staining.     

The role of vitreoretinal surgery in the management of myopic macular hole without retinal detachment

PURPOSE: To evaluate the anatomic and functional outcome of vitreoretinal surgery in eyes with pathologic myopia and macular hole and to determine if surgery improves visual acuity. METHODS: Twenty-four consecutive highly myopic eyes with full-thickness macular hole without posterior retinal detachment were treated by vitrectomy. Posterior hyaloid dissection, removal of epiretinal and internal limiting membranes (ILM) if thickened, instillation of platelet concentrate, and flushing with 25% sulfur hexafluoride were performed. RESULTS: Patients' refractive error ranged between -8.0 and -17.5 diopters, and axial length ranged from 27.1 to 31.4 mm. Two epimacular membranes and 10 macular ILM were removed. Ten patients also underwent phacoemulsification and intraocular lens implantation at the same procedure. Mean preoperative best-corrected visual acuity was 20/200. Successful anatomic macular hole closure occurred 6 months postoperatively in 100% of eyes after one (21 eyes, 87.5%) or two surgeries (3 eyes, 12.5%). Visual acuity improved three or more lines in 83.3% of patients. Mean postoperative visual acuity was 20/70. No retinal detachment was observed during the follow-up period, which ranged from 12 to 45 months. CONCLUSION: Our results suggest that vitreoretinal surgery may effectively manage myopic macular holes, thus improving anatomic and visual outcomes. By closing the hole, vitreoretinal surgery may decrease the risk of posterior retinal detachment in highly myopic eyes.     

Patent blue: a novel vital dye in vitreoretinal surgery

PURPOSE: To determine a novel vital dye (patent blue; Blueron) for vitreoretinal surgery in a prospective consecutive case series. METHODS: Five patients with either idiopathic epiretinal membrane (ERM; n = 2), proliferative vitreoretinopathy (n = 2), or a macular hole (n = 1) underwent a three-port pars plana vitrectomy. Patent blue assisted staining of the retinal surface followed by a consecutive peeling of the ERM (n = 4) or of the internal limiting membrane (ILM; n = 1) was performed. The main outcome measures were quality of intraoperative visualization of preretinal structures and postoperative visual acuity. RESULTS: The dye induced a moderate staining (++) of the ERM and a mild staining (+) of the ILM. Complete ERM and ILM removal was successfully achieved in all cases. A mean visual improvement of three Snellen lines was observed 6 months postoperatively. No visual field defects or visible retinal pigment epithelial changes were present 6 months postoperatively. CONCLUSION: Patent blue, a novel dye for intraocular applications, may be added as an alternative dye in chromovitrectomy.     

Trypan blue-assisted vitrectomy

PURPOSE: To evaluate the efficacy of trypan blue dye for the staining and removal of the internal limiting membrane, epiretinal membranes, and the posterior hyaloid during pars plana vitrectomy. METHODS: The authors retrospectively reviewed a consecutive series of 26 eyes of 26 patients in whom trypan blue 0.15% dye was used to stain intraocular tissues during vitrectomy surgery. RESULTS: The cases reviewed included the following diagnoses: epiretinal membrane (13), macular hole (9), proliferative vitreoretinopathy (2), chronic pseudophakic cystoid macular edema (1), and chronic diabetic macular edema (1). The application of trypan blue resulted in a useful and consistent bluish staining, facilitating the identification, delineation, and removal of the epiretinal membrane, internal limiting membrane, or posterior hyaloid in all patients. Six months after the surgery, visual acuity was better or the same in 21 of the 26 patients. There were no clinical signs of retinal toxicity in any patients. CONCLUSION: Trypan blue staining of the internal limiting membrane, epiretinal membranes, and the posterior hyaloid is a useful adjunct in vitreoretinal surgery and improves the efficiency and safety of membrane identification and removal.     

Epiretinal membrane surgery with or without internal limiting membrane peeling

BACKGROUND: The purpose of the present paper was to evaluate the visual outcome and recurrence rate of epiretinal membrane (ERM) formation following vitreoretinal surgery with and without internal limiting membrane (ILM) peel. METHODS: The medical records of 42 consecutive patients who underwent surgery for macular ERM by a single surgeon were reviewed. All patients underwent pars plana vitrectomy and ERM removal with a subset undergoing ILM peel. Recurrence of macular ERM within 18 months and the final visual outcome after surgery were compared between patients with and without ILM removal. RESULTS: Twenty-five patients (59.5%) underwent ERM surgery with ILM peeling and 17 patients (40.5%) underwent ERM surgery without ILM peeling. The mean preoperative logMAR visual acuity was 0.77 and 0.96 for the ILM peeling and non-ILM peeling groups, respectively. Visual acuity improved significantly in both the ILM and non-ILM peeling groups after ERM surgery (P < 0.001 and P = 0.003, respectively). Eighteen months after surgery, 3/17 eyes without ILM peeling (17.6%) developed recurrent macular ERM, compared with none of the 25 eyes with ILM peeling (log-rank test, P = 0.030). CONCLUSIONS: Internal limiting membrane removal during macular ERM surgery may minimize the recurrence of ERM, without adverse visual outcome. Further controlled prospective studies are needed to determine the role of ILM peeling in ERM surgery.     

Ultrastructural study of epiretinal membrane stained by trypan blue: 15 case reports

INTRODUCTION: Idiopathic epiretinal membrane results from detachment of the posterior hyaloid and is believed to be related to naturally occurring defects in the internal limiting membrane (ILM) of the retina. Vitrectomy and peeling are the treatment of choice. Trypan blue 0.15% (TB) stains epiretinal membrane and internal limiting membrane. It allows selective and complete removal, facilitating surgery, with less retinal damage. An ultrastructural study was conducted showing ultrastructural features of idiopathic epiretinal membranes (ERM) and those of the internal limiting membrane and its connections with the retinal side. MATERIAL AND METHODS: After pars plana vitrectomy and induction of posterior vitreous detachment, 0.2 ml TB 0.15% was injected over the ERM in an air-filled eye. The stained tissue was peeled with intraocular forceps. Specimens were at once collected in 4% glutaraldehyde for a transmission electron microscopy study. RESULTS: TB may allow complete and easier ERM and ILM peeling. The staining does not present toxic effects. The major cellular contingent is represented by glial cells, participating actively in neocollagen synthesis. Their presence supports the hypothesis of a migratory movement of retinal cells toward the vitreoretinal side. CONCLUSION: The presence of an intact internal limiting membrane, the absence of optical fibers belonging to the under retina, and the absence of any sign of apoptosis make TB a useful staining agent for ERM and ILM peeling.     

Outcomes of vitreoretinal surgery for complications of branch retinal vein occlusion

OBJECTIVE: To investigate outcomes of vitreoretinal surgery for complications of branch retinal vein occlusion (BRVO). DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: The medical records of all patients who underwent vitreoretinal surgery for complications of BRVO at Bascom Palmer Eye Institute between January 1, 1991 and December 31, 1998 were reviewed. Thirty-six eyes from 36 consecutive patients were identified. MAIN OUTCOME MEASURES: Visual acuity outcomes include preservation of preoperative visual acuity and visual acuity greater than or equal to 20/40, 20/200 and 5/200. When preoperative retinal detachment was present, the anatomic outcome assessed was complete retinal attachment. Postoperative event rates of retinal detachment, vitreous hemorrhage, epiretinal membrane (ERM), and cataract were tabulated. All outcomes were assessed at 6 months. RESULTS: Surgical indications included nonclearing vitreous hemorrhage (17 patients), traction retinal detachment involving the macula (15), and ERM (4). Mean follow-up was 19 months. Preoperatively, best-corrected vision was greater than or equal to 20/200 in 19/36 (53%) eyes. Six months postoperatively, best-corrected vision was greater than or equal to 20/40 in 12/36 (33%) eyes, greater than or equal to 20/200 in 27/36 (75%) eyes, and greater than or equal to 5/200 in 31/36 (86%) eyes. Postoperative complications included retinal detachment (2/36; 6% eyes), ERM (3; 8%), vitreous hemorrhage (2; 6%), suprachoroidal hemorrhage (1; 3%), central retinal vein occlusion (1; 3%), and central retinal artery occlusion (1; 3%). Clinical features associated with better visual outcome include better preoperative visual acuity (P: = 0.05), absence of preoperative afferent pupillary defect (P: = 0.01), and absence of preoperative macular edema (P: = 0.08). CONCLUSIONS: Following surgery, retinal attachment and improved visual acuity were achieved in the majority of patients. Pre-existing pathology and postoperative complications may limit final vision in eyes with BRVO.     

Vitreoretinal surgery using bromphenol blue as a vital stain: evaluation of staining characteristics in humans

OBJECTIVE: To evaluate the staining characteristics of bromphenol blue used during vitreoretinal surgery in humans. Patients and methods: 13 patients with epiretinal membranes were included. Before and after surgery a complete clinical examination including best corrected visual acuity, funduscopy, fluorescein angiography, OCT (Stratus), Goldmann perimetry and multifocal ERG as well as photography of the macular area was performed. Bromphenol blue was used in concentrations of 0.2% in most patients. Removed epiretinal tissue was evaluated using electron microscopy. RESULTS: Using dye concentrations of 0.2% a good demarcation of epiretinal membranes was seen in 11/13 patients. Staining of vitreous remnants at the vitreous base was seen in all patients. No dye-related adverse events were seen during follow-up in the functional tests (VA, ERG, perimetry) performed. Histological evaluation of epiretinal membranes showed unremarkable aspects of epiretinal cellular layers and unremarkable retinal surface of the internal limiting membrane (ILM). CONCLUSION: Bromphenol blue appears to be a very helpful and safe tool in posterior segment surgery. The staining characteristics need to be further evaluated in prospective study settings and larger numbers of patients.     

Novel ‘heavy’ dyes for retinal membrane staining during macular surgery: multicenter clinical assessment

Purpose: To evaluate the feasibility of two novel ‘heavy’ dye solutions for staining the internal limiting membrane (ILM) and epiretinal membranes (ERMs), without the need for a prior fluid‐air exchange, during macular surgery. Methods: In this prospective nonrandomized multicenter cohort study, the high molecular weight dyes ILM‐Blue? [0.025% brilliant blue G, 4% polyethylene glycol (PEG)] and MembraneBlue‐Dual? (0.15% trypan blue, 0.025% brilliant blue G, 4% PEG) were randomly used in vitrectomy surgeries for macular disease in 127 eyes of 127 patients. Dye enhanced membrane visualization of the ILM and ERMs, ‘ease of membrane peeling’, visually detectable perioperative retinal damage, postoperative best‐corrected visual acuity (BCVA), dye remnants and other unexpected clinical events were documented by 21 surgeons. Results: All surgeries were uneventful, and a clear bluish staining, facilitating the identification, delineation and removal of the ILM and ERMs, was reported in all but five cases. None of the surgeries required a fluid‐air exchange to assist the dye application. BCVA at 1 month after surgery improved in 83% of the eyes in the MembraneBlue‐Dual? group and in 88% in the ILM‐Blue? group. No dye remnants were detected by ophthalmoscopy, and no retinal adverse effects related to the surgery or use of the dyes were observed. Conclusion: The ‘heavy’ dye solutions ILM‐Blue? and MembraneBlue‐Dual? can be injected into a fluid‐filled vitreous cavity and may facilitate staining and removal of the ILM and/or ERMs in macular surgery without an additional fluid‐air exchange.     

Brilliant blue G selectively stains the internal limiting membrane/brilliant blue G-assisted membrane peeling

PURPOSE: To report the use of the dye brilliant blue G (BBG) for staining of the internal limiting membrane (ILM) during macular hole (MH) and epiretinal membrane (ERM) surgery. METHODS: This study was designed as an interventional, noncomparative, prospective, clinical case series. Twenty eyes from 20 consecutive patients with MH or ERM underwent BBG-assisted ILM and ERM removal. In MH cases, a posterior vitreous detachment was created, followed by the injection of 0.25 mg/mL BBG solution into the vitreous cavity and immediate washout of the BBG. This technique improved visualization of the ILM, enabling peeling and surgery to be performed successfully. However, in ERM cases, staining of the ERM could not be confirmed at this concentration. Finally, the ILM including the ERM was removed in all cases. Preoperative and postoperative ophthalmic examinations were performed. RESULTS: Postoperatively, 17 patients (85%) had visual acuity improved by at least 2 Snellen lines. No adverse effects were observed postoperatively during the observation period (mean follow-up +/- SD, 7.3 +/- 1.0 months). CONCLUSIONS: BBG selectively stains the ILM. This technique can facilitate the management of MH and ERM surgery without any adverse effects, as was shown in this short-term study.     

Prevalence and risk factors for proliferative vitreoretinopathy in eyes with rhegmatogenous retinal detachment but no previous vitreoretinal surgery

PURPOSE: To determine the prevalence of and risk factors for proliferatative vitreoretinopathy (PVR) in eyes with rhegmatogenous retinal detachment but no previous vitreoretinal surgery. DESIGN: Observational case series. METHODS: Prospective study. SETTING: A private vitreoretinal clinic in Caracas, Venezuela. STUDY POPULATION: 119 eyes of 119 patients who presented with rhegmatogenous retinal detachment but no previous vitreoretinal surgery between 1995 and 1998. OBSERVATION PROCEDURES: Data from detailed preoperative and postoperative examinations of each eye were recorded prospectively and entered into an electronic database. MAIN OUTCOME MEASURES: Prevalence of PVR of any type and severe PVR, preoperative risk factors for PVR of any type and severe PVR, effect of PVR and retinal detachment duration on initial and final visual acuity, and surgical complexity. RESULTS: The prevalence of PVR of any type was 52.9% and of severe PVR was 26.9%. The mean retinal detachment duration (+/-SD) was 58.4 (+/-129.1) days, and the mean time from initial examination to surgical treatment (+/-SD) was 24.3 (81.2) days. By univariable analysis, long retinal detachment duration, poor initial visual acuity, and large retinal detachment extent were significantly associated with PVR prevalence and severity. The presence of vitreous hemorrhage was significantly associated with PVR prevalence, and cataract was significantly associated with PVR severity. By multivariable analysis, long retinal detachment duration and large retinal detachment extent were simultaneous risk factors for PVR prevalence, while long retinal detachment, large retinal detachment extent, and poor initial visual acuity were simultaneous risk factors for PVR severity. Eyes with longer retinal detachment duration, PVR of any type, and severe PVR had worse initial and final visual acuities than eyes with shorter retinal detachment duration or those without PVR, respectively. Eyes with PVR had more complex surgery than those without PVR. CONCLUSIONS: PVR occurred very frequently in this population and was associated with more complex surgery and worse visual outcomes than among eyes without PVR. We have identified preventable risk factors associated with PVR that suggest a specific and significant need for better access to ophthalmologic care and patient education in this group of patients.     

内界膜剥除术在复杂视网膜脱离手术中的应用

目的 观察玻璃体手术中应用内界膜剥除术治疗视网膜脱离合并增生性玻璃体视网膜病变的效果.方法 回顾性分析视网膜脱离合并严重增生性玻璃体视网膜病变行玻璃体视网膜手术40例（40只眼）的临床资料.以术中是否联合内界膜剥除分为两组：剥膜组19例,未剥膜者为对照组21例.术毕均填充硅油.于玻璃体手术后3个月及硅油取出术后3个月应用OCT观察两组黄斑区视网膜水肿及视网膜前膜情况,并记录最终随访视力.结果 随访6 ～ 12个月.玻璃体切除术后3个月,OCT见黄斑视网膜前膜形成者剥膜组0眼,对照组6眼（28.57％）（Fisher确切概率法,P=0.021）;出现黄斑水肿者,剥膜组1眼（5.26％）,对照组5眼（23.81％） （x2=1.433,P =0.231）.硅油填充下视网膜复位率剥膜组为89.47％,对照组为90.48％ （x2 =0.011,P=0.916）.硅油取出术后3个月,两组病例均未再发生新的视网膜前膜;出现黄斑水肿者,剥膜组为5.3％,对照组为14.30％（x2=0.178,P=0.673）.最终随访视网膜均复位.两组患者术后视力均较术前视力明显提高,且两组间差异无统计学意义.结论 在玻璃体切除术中应用内界膜剥除术治疗视网膜脱离合并增生性玻璃体视网膜病变,可以降低术后黄斑前膜的发生率,对术后视力、黄斑水肿情况及视网膜复位成功率无明显影响.     

Efficacy of internal limiting membrane removal for retinal detachments resulting from a myopic macular hole

PURPOSE: To evaluate the efficacy of internal limiting membrane (ILM) or epiretinal membrane removal during pars plana vitrectomy for a retinal detachment resulting from a macular hole in myopic eyes. METHODS: A retrospective study was conducted in a single institution. Twenty-six highly myopic eyes with a retinal detachment resulting from a macular hole were studied. During pars plana vitrectomy, ILM peeling (ILM-peeled group) was performed on 13 eyes, and the ILM was not removed (ILM-preserved group) in 12 eyes. Main outcome measures were anatomic reattachment, optical coherence tomography-determined macular hole closure, and visual acuity. Follow-up periods were longer than 12 months in all cases. RESULTS: The anatomic reattachment rate after the initial surgery was significantly higher in the ILM-peeled group (92.3%) than in the ILM-preserved group (50%). The macular holes of 8 (72.7%) of the 11 ILM-peeled and reattached eyes and 2 (50%) of the 4 ILM-preserved and reattached eyes were successfully closed by the initial surgery. No significant difference was found in the postoperative visual acuity and the improvement of visual acuity between the ILM-peeled group and the ILM-preserved group. There was also no significant difference of the postoperative visual acuity and improvement of the visual acuity between the two groups in cases with an initial anatomic success. CONCLUSION: These results indicate that removal of the ILM contributes to a successful reattachment and is an effective treatment for macular hole and retinal detachment in highly myopic eyes. The authors suggest that the higher success rate after ILM peeling resulted from the release of the traction of the prefoveal vitreous and the epiretinal membrane over the detached retina.     

Trypan blue in macular pucker surgery: an evaluation of histology and functional outcome

PURPOSE: To evaluate possible adverse effects of trypan blue on the ultrastructure of the human retina, to report on functional outcome of macular pucker surgery with and without the use of trypan blue, and to evaluate the ultrastructure of tissue harvested during surgery. DESIGN: Experimental study and prospective matched-pair analysis of two consecutive, interventional case series. METHODS: Possible adverse effects on the ultrastructure of the human retina by trypan blue were evaluated in three donor eyes in an experimental study using trypan blue in concentrations of 0.02%, 0.15%, and 0.25%. The retinas were histologically evaluated. In the clinical study, the functional outcome (visual acuity, Goldmann perimetry) of 10 eyes of 10 consecutive patients with intraoperative use of trypan blue (0.15%) was analyzed (group 1) and compared with the functional outcome in a matched group of patients (preoperative visual acuity, pre- and postoperative lens status) who had undergone vitrectomy without trypan blue assistance (group 2). Only patients with an idiopathic macular pucker were included. Epiretinal tissue of all eyes was harvested and prepared for ultrastructural analysis using light and electron microscopy. RESULTS: In the postmortem study, no significant alterations of the inner retina suggesting adverse effects of trypan blue concentrations of 0.02% were observed. In contrast, a disorganization of the innermost retina and an absence of the internal limiting membrane (ILM) was seen after the application of undiluted 0.15% and 0.25% trypan blue. In the clinical study, the median best-corrected visual acuity was 20/50 in both groups (range, 20/200-20/40) before surgery. Mean age was 70 years in group 1 (with trypan blue) and 69 years in group 2 (without trypan blue). Mean follow-up time was 4 months in group 1 and 5.6 months in group 2. Postoperatively, median visual acuity had increased to 20/32 (range, 20/100-20/25; Wilcoxon test P = 0.01) in group 1 and to 20/40 (range, 20/100-20/25; P = 0.09) in group 2. The difference between the two groups was not statistically significant (P = 0.4). Four of 10 patients without and 7 of 10 patients with trypan blue staining experienced an improvement of visual acuity (gain of 2 lines or more). No postoperative visual field defects were noted in either group. Histologic analysis of tissue harvested intraoperatively revealed the regular picture of undisturbed fibrocellular membranes. In some specimens, a layer of interspersed collagen was noted between epiretinal cells and the ILM, suggesting two different morphologic types of macular pucker. In a few sections, areas of cellular elements were detected adjacent to the retinal surface of the ILM. CONCLUSION: Trypan blue in a concentration of 0.02% is not associated with morphologic alterations of the inner retinal layers in our postmortem study. After application of 0.15% and 0.25% trypan blue solutions, a disorganization of the inner retinal layers was observed; the ILM was absent. We did not find any adverse effects of an intraocular trypan blue concentration of 0.02% on functional status. Our study further indicates that the functional results of surgery with and without the use of trypan blue are comparable. As the question of toxicity of a dye can not be answered by morphological observations alone, further experimental studies will be needed.     

Perifoveal traction retinal detachment following successful optic disc pit surgery

A 25-year-old male presented 8 years after a successful vitreoretinal operation for a left optic disc pit (ODP). On presentation his visual acuity had reduced from 6/5 (20/15) to 6/12 (20/40) in his operated eye. On examination an annular serous retinal detachment possibly secondary to tangential traction by either the internal limiting membrane (ILM) or residual lamellar vitreous cortex or both around the peripheral macular area was seen. The central fovea was flat. Following an uncomplicated vitrectomy and ILM peel, visual acuity improved to 6/6 (20/20) postoperatively. The author suggests that traction forces are responsible for the development of the serous detachment in eyes with ODP. Epiretinal membranes together with the ILM should be removed in all patients undergoing therapy for a retinal detachment associated with ODP in an effort to initially achieve a further relief of all forces and to try to avoid the late retinal detachment associated with epiretinal membrane or ILM contraction.     

Trypan blue- and indocyanine green-assisted epiretinal membrane surgery: clinical and histopathological studies

PURPOSE: To evaluate the clinical outcome and electron microscopic findings of trypan blue (Tb) and indocyanine green (ICG) assisted epiretinal membrane (ERM) surgery. METHODS: This is a prospective consecutive noncomparative interventional case series. After pars plana vitrectomy, 0.1 ml of 0.6 mg/ml Tb solution was applied for 1 min under air for ERM staining. After ERM removal, internal limiting membrane (ILM) was further peeled after staining with 0.2 ml of 1 mg/ml ICG solution. Intraoperative specimens were sent for electron microscopy. Tb was considered useful if the edge of ERM was stained where peeling could be initiated with a clearer visualisation of the overall extent of the ERM. RESULTS: In all, 16 eyes from 16 patients were recruited. There were nine grade 1 ERMs, five grade 2 ERMs, and two grade 3 ERMs. Tb was useful in six (67%) of the nine eyes with grade 1 ERMs and in all eyes with grade 2 or 3 ERMs. The three remaining grade 1 ERMs were removed together with surrounding ILM that was stained by ICG. The mean line of improvement was 1.3 lines with the median BCVA improved from 6/12 to 6/9. All 16 eyes had symptomatic improvement and none developed ERM recurrence. No complication related to Tb or ICG was observed clinically or angiographically. Electron microscopy of the Tb-stained ERM specimens showed fragments of ILM in all specimens. CONCLUSIONS: Tb and ICG are useful intraoperatively to improve the visualisation and facilitate complete removal of ERM and ILM in macular ERM surgery.     

Clinical Outcomes of Double Staining and Additional ILM Peeling during ERM Surgery

Purpose

To assess the clinical outcomes in idiopathic epiretinal membrane (ERM) patients after vitrectomy and ERM removal with or without additional indocyanine green (ICG)-assisted internal limiting membrane (ILM) peeling.

Methods

The medical records of 43 patients with an idiopathic ERM that underwent vitrectomy and ERM removal between July 2007 and April 2010 were reviewed. The patients were divided into two groups: triamcinolone-assisted simple ERM peeling only (group A, n = 23) and triamcinolone-assisted ERM peeling followed by ICG staining and peeling of the remaining internal ILM (group B, n = 20).

Results

No difference was found between the two groups in terms of visual acuity, macular thickness, P1 amplitude or implicit time on multifocal-electroretinogram (mfERG) at six and 12 months postoperatively. In group B, ICG staining after ERM peeling demonstrated that the ILM had been removed together with the ERM in 12 eyes (60%), and all 12 eyes showed punctate retinal hemorrhages during ERM peeling. There was no recurrence of an ERM in either group.

Conclusions

Additional procedures involving ICG staining and ILM peeling during ERM surgery do not appear to have an additive effect on the clinical outcomes in terms of visual acuity, retinal function based on mfERG, or recurrence rate.     

Vitrectomy for epiretinal membranes: visual outcome and prognostic criteria

The treatment of choice for epiretinal membranes (ERM) causing marked retinal distortion and substantial visual impairment remains vitreoretinal surgery. The purpose of this study was to evaluate the results of surgery performed in our department and to investigate the prognostic value of different factors such as preoperative best-corrected visual acuity (BCVA), pre-existing cystoid macular edema (CME), intra-operative peeling of the internal limiting membrane (ILM), age and duration of symptoms. Eighty-eight consecutive eyes of 88 patients were operated on for ERM from July 1998 to June 2000. Both idiopathic and secondary cases were included. In all cases the ERM was successfully removed from the fovea. Mean BCVA after surgery increased from Snellen 0.2 (hand motion (HM) - 0.6) to Snellen 0.5 (HM - 1.0) (p<0.0001). Our results confirm the efficacy of surgical removal of the ERM in improving the visual acuity. Although not statistically significant, mean postoperative BCVA was slightly better in the group without pre-existing CME (p>0.05) and in the group where peeling of the ILM was performed (p>0.05). The data suggest that early surgery is likely to decrease the risk of developing irreversible macular damage (p<0.05). Because accelerated nuclear sclerosis with visual impairment is a common phenomenon after vitrectomy, one might consider performing a phaco-emulsification at the same time, especially in the elderly.     

Trypan blue staining of internal limiting membrane and epiretinal membrane during vitrectomy: visual results and histopathological findings

AIMS: To report on the use of trypan blue (TB) 0.06% for staining the internal limiting membrane (ILM) and epiretinal membrane (ERM) during vitrectomy and report on their histology. METHOD: 14 consecutive patients with idiopathic macular hole or macular pucker (seven patients each) were prospectively recruited for ILM or ERM peel respectively. After pars plana vitrectomy and induction of posterior vitreous detachment, 0.5 ml TB 0.06% in phosphate buffered saline (VisonBlue) was injected over the posterior pole in an air filled eye and left for 2 minutes. The stained tissue was peeled with intraocular forceps. Specimens were evaluated using histochemical and immunohistochemical methods. RESULTS: The average follow up was 4.4 months. Internal limiting membranes and epiretinal membranes were stained satisfactorily in all cases and removed successfully. Eight patients (57%) had improvement of 2 or more Snellen lines. All seven macular holes closed. In the ERM cases, no residual membranes were observed clinically, at the latest follow up. No complications relating to the use of the dye were encountered intraoperatively or postoperatively. Of the 14 procedures, nine (four macular hole and five macular pucker) yielded sufficient tissue for histopathological evaluation. Histological and immunohistological assessment revealed that the morphology of these specimens was similar to that observed in macular hole ILM and macular pucker ERM removed without the aid of dye. CONCLUSION: TB staining facilitated the identification and delineation of ILM and ERM removal during the surgical management of macular holes and macular pucker. The visual outcome of this series and the specimens removed suggest they are no different from those without TB staining. Its use in posterior segment appears to be safe but further studies are required to investigate its long term safety.