Retrospective study of macular holes treated with pars plana vitrectomy

Selective ILM Staining and Safety of Two Vital Dyes During a Human-Like Pars Plana Vitrectomy Ex Vivo in Porcine Eyes

PURPOSE

An ideal dye for intraocular use should effectively stain the target tissue while being easy to apply and remove. Additionally, it should not have any adverse effects resulting from prolonged contact with the retinal tissue. Recently, concerns have been raised about the safety of some vital dyes during surgical procedures as they may cross the internal limiting membrane and deposit on the retina. In this study, we aimed to investigate whether commercially available vital dyes, VIEW-ILM® and TWIN® (AL.CHI.MI.A. S.r.l., Ponte San Nicolò, Padova, Italy), have the potential to cross the internal limiting membrane during vitreoretinal surgery and deposit on the retina. Furthermore, we evaluated their safety in vitro and in vivo.

METHODS

A human-like pars plana vitrectomy was performed on porcine eyes ex vivo, with VIEW-ILM® or TWIN® used to stain the internal limiting membrane either with or without subsequent internal limiting membrane peeling. The two dyes were then extracted from retinal punches with or without internal limiting membrane, and quantified using high performance liquid chromatography. Safety was evaluated through in vitro cytotoxicity tests and in vivo skin sensitization and irritation tests according to ISO standards.

RESULTS

High performance liquid chromatography analyses demonstrated that VIEW-ILM® and TWIN® effectively stained the internal limiting membrane without crossing the membrane. No residual dyes were found in the retinal layers after internal limiting membrane removal. Furthermore, both in vitro and in vivo safety tests confirmed the absence of cytotoxicity, skin sensitization, and irritation.

CONCLUSION

The results of this study support the safety and efficacy of VIEW-ILM® and TWIN® for internal limiting membrane staining. The experimental protocol described in this study could be utilized to gain a comprehensive understanding of the characteristics of vital dyes.

In-Office Sulfur Hexafluoride (SF6) Injection to Close Recently Operated or Reopened Macular Holes: A Minimal Approach Technique

To describe an in-office minimal approach technique for closing recently operated full thickness macular holes (FTMH), when closure was not fully achieved or there was macular hole re-formation, without performing another pars plana vitrectomy (PPV). Retrospective case series study. Nine patients were included in this case series. All patients were diagnosed with FTMH characterized by a decrease in visual acuity (VA) and metamorphopsias. All patients initially underwent a standard PPV procedure with 20% sulfur hexafluoride (SF6) injection. After 1-16 weeks, no closure or reformation of the macular hole was observed. Fluid-SF6 exchange was performed in the slit lamp, with the aim of injecting a 50% gas bubble of pure SF6 into the vitreous cavity, according to a minimally invasive in-office technique. Postoperatively, all patients achieved successful macular hole closure and VA showed an average improvement of approximately 4 lines on the EDTRS logarithm of the minimum angle of resolution (logMAR) chart. In particular, the mean corrected distance visual acuity improved from 0.99 ± 0.27 logMAR to 0.33 ± 0.23 logMAR (P = 0.03). The minimal surgical in-office technique of SF6 injection for the management of reopened macular holes after a recent PPV procedure shows promising results.

Long-Term Outcomes after Macular Hole Surgery

PURPOSE

To evaluate the structural and visual outcomes after pars plana vitrectomy (PPV) for idiopathic full-thickness macular hole (MH) with at least 5 years of follow-up information.

DESIGN

Retrospective case series.

PARTICIPANTS

Patients with idiopathic MH who had at least 5 years of follow-up information after PPV.

METHODS

Best-corrected visual acuity (BCVA) was recorded preoperatively and, when available, at 1, 2, 3, 5, 8, and 10 years after surgery. Reestablishment of the postoperative integrity of the ellipsoid zone (EZ) and the external limiting membrane (ELM) and presence of cystoid spaces were evaluated using spectral-domain (SD) OCT.

MAIN OUTCOME MEASURES

Postoperative BCVA and its correlation with different SD OCT parameters.

RESULTS

Eighty-seven eyes of 80 patients with a mean age at surgery of 68.9±7.03 years were included. The mean postoperative follow-up was 9.6±4.3 years (median, 9 years; range, 5-22 years). The mean preoperative BCVA was 0.20±0.14 (range, 0.03-0.66). Postoperative BCVA was improved at all time points compared with preoperative BCVA (P < 0.05). Improvement in the postoperative BCVA remained stable 10 years after surgery. Initial successful closure of MH was achieved in 82 eyes (94%). Macular hole reopening occurred in 7 eyes (8.0%). Eleven eyes (13%) were reoperated: 4 eyes (4.5%) for persistence and 7 eyes (8.0%) for reopening of MH. Indocyanine green (ICG) stain was used in 22 eyes (25.2%). Among 57 patients (66%) who were phakic before surgery, 52 eyes (91.2%) underwent cataract extraction after PPV at a mean duration of 32.7±38.5 months (range, 2-187 months). Postoperative EZ integrity was restored in 52 eyes (60%), ELM integrity was restored in 54 eyes (62%), and cystoid spaces of variable severity were observed in 28 eyes (32%). Preoperative BCVA of 20/60 or better and postoperative reestablished ELM and EZ integrity were associated significantly with better postoperative BCVA at different postoperative follow-up visits (P < 0.05).

CONCLUSIONS

Visual acuity improvement after MH surgery continued during the first 3 years after PPV and was maintained thereafter in a substantial fraction of patients, and final BCVA correlated with better preoperative BCVA and better postoperative OCT parameters.

Material properties of the internal limiting membrane and their significance in chromovitrectomy

Intraoperative visualization of the internal limiting membrane (ILM), the choice of a point of vantage for lifting an initial flap, the precision with which the ILM is grasped, adhesion between the forceps and the ILM, thickness, stiffness and elasticity of the ILM as well as monitoring of the completeness of ILM removal are all important factors for safety and efficacy of a chromovitrectomy intervention. The understanding of the underlying physical features of the ILM, such as contrast behavior and bioanatomical and biomechanical properties represent, thus, useful prerequisites for successful macular surgery. New analytical tools, such as atomic force microscopy and chromaticity analysis, allow new insights into ILM material characteristics, permitting a systematic approach to refinement of surgical technique. .

The options to minimize the surgical trauma to treat ocular diabetic complications and to improve postoperative recovery and quality of life require an individualized approach

Within the past ten years, small incision pars-plana vitrectomy, and refined microsurgical techniques, together with the introduction of various intravitreally applied drugs, significantly improved the anatomical and functional outcome. Unfortunately many diabetic patients with vitreoretinal complications also have cataract. In diabetic retinopathy, the benefit of simultaneous cataract surgery was long under debate due to possible side effects such as fibrinous reaction or secondary glaucoma. We review recent reports about the results of PPV for complication of diabetic retinopathy and the influence of a simultaneous cataract surgery, that compare different surgical approaches. Pars plana vitrectomy carried out with conventional 0,9 mm incisions (20G PPV) were related to higher incidences of postoperative inflammatory reactions and to a higher frequency of postoperative hypertensive events as compared to small incision vitrectomy (23G PPV). Postoperative recovery was faster in eyes with 23G surgery than after 20G surgery, with no delay by a simultaneous cataract surgery. A 23G-PPV improves the postoperative recovery and the quality of life for the diabetic patient. Cataract is no longer an obstacle for a vitreoretinal surgery. Postoperative recovery is faster and the new technique has less side effects than the conventional technique. In the future, a drug assisted vitrectomy will further reduce the surgical trauma. However, the new options are not equally benefitial for all patients. A further improvement in the quality of life will require a more individualized approach of microsurgical treatment for ocular complications of diabetes.

Tailored vitrectomy and laser photocoagulation without scleral buckling for all primary rhegmatogenous retinal detachments

AIM

To investigate the anatomical and functional results and the complications in eyes operated on using vitrectomy without scleral buckling for all forms of rhegmatogenous retinal detachment (RRD).

METHODS

All cases of primary RRD at the University Hospital of Lund, Lund, Sweden, treated by one surgeon during a period of 3 years were retrospectively reviewed. In 131 (98%) of 134 consecutive cases, a final follow-up record of 3-14 months was obtained, and these eyes were included in the study. The surgical protocol was tailored for each case and consisted of vitrectomy, laser photocoagulation and tamponade. Preoperative and intraoperative variables were analyses for risk for redetachment and postoperative proliferative vitreoretinopathy (PVR).

RESULTS

Complete reattachment was achieved in 87% of cases (114/131) after one operation and in 95% cases after > or =1 operation. A primary detachment of >1 quadrant was the only significant risk factor for redetachment (p<0.05). The most common cause of redetachment was progressive PVR. Significant risk and factors for PVR postoperatively were a poor preoperative visual acuity and a high number of laser effects during surgery (p<0.05). The visual acuity for the total number of eyes, macula-off eyes, and pseudophakic as well as phakic eyes, improved significantly. The visual acuity for macula-on eyes did not change significantly. Six patients developed ocular hypertension and another 6 an epiretinal membrane. Three patients reported a visual field defect. Increased lens opacification was seen in 64 of the 94 (68%) phakic eyes.

CONCLUSIONS

The tailored vitrectomy protocol is well suited to all types of RRD. Increased lens opacification in phakic eyes is common, but visual acuity is considerably improved in phakic as well as pseudophakic eyes. PVR development postoperatively is related to the extent of laser treatment, indicating that the protocol may be even further optimised in the future.

Long-term follow-up of indocyanine green–assisted peeling of the retinal internal limiting membrane during vitrectomy surgery for idiopathic macular hole repair

OBJECTIVE

To determine the long-term efficacy of indocyanine green (ICG)-assisted retinal internal limiting membrane (ILM) peeling during macular hole repair.

DESIGN

Retrospective, interventional, noncomparative case series.

PARTICIPANTS

One hundred twenty-one eyes of 114 patients with stage 2, 3, or 4 idiopathic macular holes that underwent ICG-assisted macular hole repair during the period of August 1999 to January 2003.

INTERVENTION

All eyes underwent a pars plana vitrectomy, including peeling of the posterior cortical hyaloid when necessary. Indocyanine green dye (0.5%) was instilled over the macula, and after removal of the ICG, the retinal ILM was peeled. Medium- to long-acting gas tamponade was used in all cases, and all patients were asked to position themselves facedown for 1 to 2 weeks.

MAIN OUTCOME MEASURES

Long-term postoperative anatomic results, visual acuity (VA), and complications.

RESULTS

Patients were observed postoperatively for an average of 26 months (range, 12-53). Anatomic closure of the macular hole was achieved in 118 eyes (98%) with a single surgery. Reoperation was successful at closing 2 of the 3 macular holes that did not close initially. One macular hole reopened 16 months after the original surgery, and the patient has not yet undergone further surgery. Visual acuity improved by > or =2 lines in 116 eyes (96%). Mean visual improvement after surgery was 6 lines (range, 0-14), and 96 eyes (79%) achieved a final VA of 20/50 or better. There were no intraoperative or postoperative complications attributed to the use of ICG.

CONCLUSIONS

Long-term follow-up of patients who underwent ICG-assisted ILM peeling for idiopathic macular hole repair demonstrates excellent anatomic and visual results.

Long-term anatomic and visual acuity outcomes after initial anatomic success with macular hole surgery

PURPOSE

To investigate the anatomic and visual outcomes in patients with initial anatomic success after macular hole surgery and with at least 5 years of follow-up.

DESIGN

Retrospective, noncomparative, consecutive case series.

METHODS

Medical records of all patients who underwent surgery for idiopathic full-thickness macular holes by two surgeons (W.E.S., H.W.F.) at the Bascom Palmer Eye Institute between January 1, 1991, and December 31, 1996, were reviewed. All patients who had initial anatomic success with macular hole surgery and who had 5 years or more of follow-up postoperatively were included in the study. Main outcome measures included the rate of macular hole reopening and visual acuity outcomes.

RESULTS

Seventy-four eyes of 66 patients with a median age of 68.0 years (range, 45.0-86.8 years) were identified. The median duration of macular hole was 6.0 months (range, 1.1-93.8 months), and the median duration of follow-up after macular hole surgery was 91.0 months (range, 60.0 to 114.8 months). The hole reopened in 9 eyes (12%) during the follow-up interval; 6 of these eyes underwent reoperation, and the hole closed in 4 of 6 (67%). Preoperative visual acuity ranged from 20/50 to 20/400 (mean, 20/129; median, 20/100). In the 62 eyes that underwent cataract extraction (CE) after macular hole surgery, CE was performed at a median of 13.9 months after macular hole surgery. Patients achieved their best postoperative visual acuity at a median of 28.5 months after macular hole surgery. Best postoperative visual acuity ranged from 20/20 to 20/400 (mean, 20/36; median, 20/30). Visual acuity at last follow-up ranged from 20/25 to counting fingers (mean, 20/56; median, 20/40). At last follow-up, 43 eyes (58%) had a visual acuity of 20/40 or better, and 57 (77%) had an improvement in visual acuity of 3 or more Snellen lines compared with their preoperative acuity.

CONCLUSIONS

Macular hole closure and visual acuity improvement after initially successful macular hole surgery persist at follow-up of 5 years and longer in the majority of patients; delayed visual acuity improvement is not attributable to cataract surgery alone.

Effect of indocyanine green intraocular stain on human and rabbit corneal endothelial structure and viability. An in vitro study

PURPOSE

To evaluate the direct effect of intraocular indocyanine green (ICG) on endothelial cell function, ultrastructure, and viability in human and rabbit corneas.

SETTING

A laboratory evaluation study.

METHODS

Paired human and rabbit corneas were mounted in an in vitro specular microscope for endothelial cell perfusion. One corneal endothelium was perfused with 25 mg ICG dissolved in 0.5 mL aqueous solvent in 4.5 mL balanced salt solution (BSS(R)) for 3 minutes followed by washout with a control solution. The percentage of ICG exposed to the corneal endothelium was 0.5%. The paired cornea was perfused with the same solution without ICG, followed by the washout. The corneas were fixed for scanning and transmission electron microscopy (TEM). In another group, the endothelial viability was determined using a live cell/dead cell assay.

RESULTS

In rabbit corneas, the mean corneal swelling rate was 12.9 microm/h +/- 1.2 (SEM) in the ICG corneas and 2.8 +/- 1.9 microm/h in the controls. Scanning electron microscopy and TEM revealed a normal endothelial cell mosaic. The control electron micrographs were similar. In human corneas, the mean swelling rate was 19.1 +/- 2.8 microm/h in the ICG corneas and 19.2 +/- 2.6 microm/h in the controls. Scanning electron microscopy and TEM revealed intact junctions with slight cellular vacuolization, similar to that in the controls. In the live cell/dead cell subgroup, the mean damage was 17.3% +/- 1.7% in the ICG-exposed corneas and 22.0% +/- 8.9% in the controls.

CONCLUSIONS

Three-minute exposure to ICG in BSS had no adverse effect on corneal endothelial function, ultrastructure, or viability in human and rabbit corneas. This study provides a safety profile for the corneal endothelium when ICG is used as an intraocular tissue stain in ophthalmic surgery.

Vitrectomy for retinal detachments with both peripheral retinal breaks and macular holes. An assessment of outcome and the status of the macular hole

PURPOSE

To establish the effectiveness of vitrectomy and gas tamponade for treating retinal detachments due to peripheral retinal breaks with an associated macular hole and to discover the status of the macular hole at long-term follow-up.

METHODS

Twenty-three consecutive patients with combined peripheral break and macular hole retinal detachments were treated by pars plana vitrectomy. The main outcome measures were reattachment of the retina and status of the macular hole.

RESULTS

Seventy-eight percent of the operations were successful in reattaching the retina initially, improving to 87% after two patients had another operation. Three patients declined further surgery. Long-term follow-up of macular hole status was possible in 16 cases. Closure rate was 31%.

CONCLUSION

Pars plana vitrectomy with gas tamponade is an effective method of treating this form of retinal detachment. Some macular holes close after this surgery.

Indocyanine green-assisted peeling of the retinal internal limiting membrane during vitrectomy surgery for macular hole repair

OBJECTIVE

To determine the efficacy and safety of indocyanine green (ICG)-assisted retinal internal limiting membrane (ILM) peeling during macular hole repair.

DESIGN

Interventional, noncomparative, prospective case series.

PARTICIPANTS

Twenty-four consecutive patients (24 eyes) with stage 3 or 4 macular holes.

INTERVENTION

All eyes underwent a pars plana vitrectomy, including peeling of the posterior cortical hyaloid when necessary. Indocyanine green dye (0.5%) was instilled into the posterior vitreous cavity over the macula and left in place for 3 to 5 minutes. After removal of the ICG, the retinal ILM was peeled. Medium- to long-acting gas tamponade was used in all cases, and all patients were asked to position face down for 1 to 2 weeks.

MAIN OUTCOME MEASURES

Intraoperative staining properties of ICG, technical ease of peeling of the retinal ILM, postoperative anatomic results, visual acuity, and complications were recorded.

RESULTS

Indocyanine green stained the retinal ILM, but did not stain the underlying retina. Indocyanine green staining greatly facilitated the surgeons' ability to visualize and peel the ILM in each case. Peeled tissue was sent for both light and electron microscopic studies, which confirmed that the ICG-stained tissue was truly retinal ILM. Patients were observed after surgery for an average of 123 days (range, 23-195 days). Anatomic closure of the macular hole was achieved in 21 eyes (88%) with a single surgery. Visual acuity improved in 23 of 24 patients (96%) after surgery. There were no intra- or postoperative complications related to ICG use, and there was no clinical or fluorescein angiographic evidence of ICG toxicity.

CONCLUSIONS

Indocyanine green stains the retinal ILM. This property facilitates ILM peeling by providing a stark contrast between the stained ILM and the unstained retina. Indocyanine green staining of the ILM appears to be a safe and useful adjunct in vitreous surgery for macular hole repair.

Indocyanine green-assisted peeling of the retinal internal limiting membrane

OBJECTIVE

To determine whether indocyanine green (ICG) stains and facilitates peeling of the retinal internal limiting membrane (ILM). To investigate the different staining properties of the posterior cortical hyaloid, retinal ILM, and the retina after ILM removal.

DESIGN

Autopsy eye study.

MATERIALS

Eleven human cadaveric eyes.

METHODS

Open sky vitrectomy including removal of the posterior cortical vitreous was performed. A 0.5% ICG solution was then injected into the posterior vitreous cavity over the macula. The dye was allowed to settle on the macula for 5 minutes and was then removed by mechanical aspiration. Peeling of the ILM was initiated with a bent needle and completed with intraocular forceps. Specimens were submitted for light and electron microscopy.

MAIN OUTCOME MEASURES

Staining properties and ease of peeling of retinal ILM were evaluated. Retinal ILM removal was confirmed by histopathologic and electron microscopic examination.

RESULTS

ICG contact with the retinal surface resulted in bright green staining of the ILM. This stain greatly facilitated ILM peeling by improving direct visualization of the membrane. The underlying retina did not stain, thus providing a clear distinction between the stained ILM and the unstained retina. Continuous circular peeling of the ILM was easily completed with this technique. Light microscopic and ultrastructural studies confirmed removal of the ILM.

CONCLUSIONS

ICG solution distinctly stains the nearly invisible retinal ILM in human cadaveric eyes. ICG staining greatly facilitates ILM peeling by providing a stark contrast between the stained ILM and the unstained retina.