Full-thickness macular holes treated with vitrectomy and tissue glue

BioAdhere: tailor-made bioadhesives for epiretinal visual prostheses

Introduction: Visual prostheses, i.e. epiretinal stimulating arrays, are a promising therapy in treating retinal dystrophies and degenerations. In the wake of a new generation of devices, an innovative method for epiretinal fixation of stimulator arrays is required. We present the development of tailor-made bioadhesive peptides (peptesives) for fixating epiretinal stimulating arrays omitting the use of traumatic retinal tacks. Materials and methods: Binding motifs on the stimulating array (poly[chloro-p-xylylene] (Parylene C)) and in the extracellular matrix of the retinal surface (collagens I and IV, laminin, fibronectin) were identified. The anchor peptides cecropin A (CecA), KH1, KH2 (author's initials) and osteopontin (OPN) were genetically fused to reporter proteins to assess their binding behavior to coated microtiter plates via fluorescence-based assays. Domain Z (DZ) of staphylococcal protein A was used as a separator to generate a bioadhesive peptide. Following ISO 10993 "biological evaluation of medical materials", direct and non-direct cytotoxicity testing (L-929 and R28 retinal progenitor cells) was performed. Lastly, the fixating capabilities of the peptesives were tested in proof-of-principle experiments. Results: The generation of the bioadhesive peptide required evaluation of the N- and C-anchoring of investigated APs. The YmPh-CecA construct showed the highest activity on Parylene C in comparison with the wildtype phytase without the anchor peptide. eGFP-OPN was binding to all four investigated ECM proteins (collagen I, laminin > collagen IV, fibronectin). The strongest binding to collagen I was observed for eGFP-KH1, while the strongest binding to fibronectin was observed for eGFP-KH2. The selectivity of binding was checked by incubating eGFP-CecA and eGFP-OPN on ECM proteins and on Parylene C, respectively. Direct and non-direct cytotoxicity testing of the peptide cecropin-A-DZ-OPN using L-929 and R28 cells showed good biocompatibility properties. Proof-of-concept experiments in post-mortem rabbit eyes suggested an increased adhesion of CecA-DZ-OPN-coated stimulating arrays. Conclusion: This is the first study to prove the applicability and biocompatibility of peptesives for the fixation of macroscopic objects.

Assessment of the Retinal Toxicity and Sealing Strength of Tissue Adhesives

PURPOSE

The purpose of this in vitro prospective nonrandomized study is to compare the toxicity and strength of cyanoacrylate and hydrogel adhesives on human retinal pigment epithelium (RPE) cells and porcine retina, respectively.

METHODS

The toxicity of cyanoacrylate (histoacryl, dermabond, superglue), ReSure PEG, and Tisseel fibrin glue on human RPE cells was determined by growing RPE cells in vitro, applying the different adhesives to the cells, and monitoring for disruption of growth over 3 days. The relative strength of these adhesives was tested by gluing a 3 mm piece of foam to a porcine retina and determining the amount of force needed to break the attachment.

RESULTS

0.085 N of force was required to break the porcine retinal tissue (p = .913). Histoacryl adhesive exhibited high strength (0.247 N) and high RPE toxicity (0.55 mm inhibition zone after 24 hrs). The strength of Tisseel fibrin glue was 0.078 N while that of ReSure was only 0.053 N. Both Tisseel and ReSure were nontoxic to the RPE cells.

CONCLUSIONS

Tisseel VH fibrin sealant may provide the best option for sealing retinal breaks because of its high strength and low retinal toxicity.

Autologous Platelet-Rich Fibrin in the Treatment of Refractory Macular Holes

Purpose

To describe a novel method for the treatment of refractory macular holes.

Methods

Two case reports on the use of autologous platelet rich fibrin (PRF), followed by sulfur hexafluoride gas tamponade to facilitate closure of refractory macular holes.

Results

Macular holes were succesfully closed within a week in both cases. Best corrected Snellen visual acuities improved from counting fingers to 0.16 in the first case, and from 0.05 to 0.2 in the second case. No complication occurred during or after the procedures.

Conclusion

The use of autologous PRF seems to be a safe and effective alternative method for the treatment of refractory macular holes. Further experience and studies are required to assess the value of autologous PRF in the management of challenging macular hole cases of different etiologies. To the best of our knowledge, this is the first use of autologous PRF in the treatment of macular holes.

Surgical adhesives in ophthalmology: history and current trends

Tissue adhesives are gaining popularity in ophthalmology, as they could potentially reduce the complications associated with current surgical methods. An ideal tissue adhesive should have superior tensile strength, be non-toxic and anti-inflammatory, improve efficiency and be cost-effective. Both synthetic and biological glues are available. The primary synthetic glues include cyanoacrylate and the recently introduced polyethylene glycol (PEG) derivatives, while most biological glues are composed of fibrin. Cyanoacrylate has a high tensile strength, but rapidly polymerises upon contact with any fluid and has been associated with histotoxicity. Fibrin induces less toxic and inflammatory reactions, and its polymerisation time can be controlled. Tensile strength studies have shown that fibrin is not as strong as cyanoacrylate. While more research is needed, PEG variants currently appear to have the most promise. These glues are non-toxic, strong and time-effective. Through MEDLINE and internet searches, this paper presents a systematic review of the current applications of surgical adhesives to corneal, glaucoma, retinal, cataract and strabismus surgeries. Our review suggests that surgical adhesives have promise to reduce problems in current ophthalmic surgical procedures.

Fibrin glue versus sutures for conjunctival autografting in primary pterygium surgery

BACKGROUND

Pterygium, a growth of the conjunctiva over the cornea, is a progressive disease leading in advanced stages to visual impairment, restriction of ocular motility, chronic inflammation and cosmetic concerns. Surgical removal is the treatment of choice, but recurrence can be a problem. Currently the best surgical option in terms of recurrence is conjunctival autograft. To date the most common surgical methods of attaching conjunctival autografts to the sclera are through suturing or fibrin glue. Each method presents its own advantages and disadvantages. Sutures require considerable skill from the surgeon and can be associated with a prolonged operation time, postoperative discomfort and suture-related complications, whereas fibrin glue may give a decreased operation time, improve postoperative comfort and avoid suture-related problems.

OBJECTIVES

To assess the effectiveness of fibrin glue compared to sutures in conjunctival autografting for the surgical treatment of pterygium.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 9), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to October 2016), Embase (January 1980 to October 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 14 October 2016.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in any setting where fibrin glue was compared with sutures to treat people with pterygium.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results, assessed trial quality, and extracted data using standard methodological procedures expected by Cochrane. Our primary outcome was recurrence of pterygium defined as any re-growth of tissue from the area of excision across the limbus onto the cornea. The secondary outcomes were surgical time and complication rate. We graded the certainty of the evidence using GRADE.

MAIN RESULTS

We included 14 RCTs conducted in Brazil, China, Egypt, India, Malaysia, New Zealand, Philippines, Saudi Arabia, Sweden and Turkey. The trials were published between 2004 and 2016, and were assessed as a mixture of unclear and low risk of bias with three studies at high risk of attrition bias. Only adults were enrolled in these studies.Using fibrin glue for the conjunctival autograft may result in less recurrence of pterygium compared with using sutures (risk ratio (RR) 0.47, 95% CI 0.27 to 0.82, 762 eyes, 12 RCTs; low-certainty evidence). If pterygium recurs after approximately 10 in every 100 surgeries with sutures, then using fibrin glue may result in approximately 5 fewer cases of recurrence in every 100 surgeries (95% CI 2 fewer to 7 fewer cases). Using fibrin glue may lead to more complications compared with sutures (RR 1.92; 95% CI 1.22 to 3.02, 11 RCTs, 673 eyes, low-certainty evidence). The most common complications reported were: graft dehiscence, graft retraction and granuloma. On average using fibrin glue may mean that surgery is quicker compared with suturing (mean difference (MD) -17.01 minutes 95% CI -20.56 to -13.46), 9 RCTs, 614 eyes, low-certainty evidence).

AUTHORS' CONCLUSIONS

The meta-analyses, conducted on people with pterygium in a hospital or outpatient setting, show fibrin glue may result in less recurrence and may take less time than sutures for fixing the conjunctival graft in place during pterygium surgery. There was low-certainty evidence to suggest a higher proportion of complications in the fibrin glue group.

Ocular Biocompatibility of Poly-N-Isopropylacrylamide (pNIPAM)

Purpose. To study the safety of intravitreal injections of poly-N-isopropylacrylamide (pNIPAM) tissue adhesive in rabbit eyes. Methods. Twelve study rabbits received an intravitreal injection of 0.1 mL 50% pNIPAM in the right eye. Follow-up examinations included color fundus photography, fundus fluorescein angiography (FA), optical coherence tomography (OCT), and electroretinography (ERG). Subsequent to the last follow-up assessment, the rabbits were sacrificed and histopathological study on the scleral incision sites was performed. Results. All study animals developed mild to moderate levels of inflammatory reaction in the conjunctiva, anterior chamber, and the anterior vitreous during the first month of follow-up. After this period, the level of the inflammatory reaction progressively decreased and completely disappeared after the third month of follow-up. The lens and cornea remained clear during the entire follow-up period. OCT and FA did not show areas of retinal damage or neovascularization. Histological and ERG studies of eyes injected with pNIPAM demonstrated absence of retinal toxicity. Conclusion. Intravitreal injections of pNIPAM were nontoxic in this animal study, and pNIPAM may be safe to be used as a bioadhesive in certain retinal diseases.

Glued intraocular lens implantation for eyes with defective capsules: A retrospective analysis of anatomical and functional outcome

PURPOSE

To analyze the anatomical and functional outcome of glued intra ocular lens (IOL) implantation technique and its modifications.

DESIGN

Retrospective observational case series.

METHODS

This is a retrospective analysis of the patients who underwent glued intra ocular lens implantation from December 2007 to August 2010. Post operative uncorrected vision, best corrected visual acuity (BCVA), intra ocular pressure, IOL position, endothelial cells and anterior chamber reaction at their last follow up are analyzed from their concerned case sheets documentation. Subjective changes are analyzed via individual questionnaire. Immediate and late postoperative complications are also evaluated. Surgical modifications and the difference in the operated eyes are analyzed.

RESULTS

Total 210 glued IOL eyes have been reviewed. Out of this 210, there are 152 (PMMA glued IOL), 21 (three piece foldable IOL), 5 (multifocal foldable IOL), 12 (pediatric glued IOL), 5 (20G sutureless vitrectomy), 2 (glued iris prosthesis) and 3 (transposition of posterior chamber IOL into anterior chamber). In combined surgeries there are, 5 (optical penetrating keratoplasty), 2 (descemet's stripping endothelial keratoplasty) and 3 (iridoplasty). The modifications in glued IOL are handshake technique, injectable or foldable glued IOL, Multifocal glued IOL and intraoperative 23/25G trocar cannula infusion. Decentration (1.97%), macular edema (1.97%) and optic capture (2.63%) are the post operative complications encountered in rigid glued IOL. Good patient satisfaction is seen in the eyes with IOL repositioning, IOL exchange and multifocal glued IOL. There is significant improvement in BCVA in PMMA IOL (p = 1.35 × 10(-5)) and foldable IOL (p = 0.000).

CONCLUSION

Glued IOL seems to be a good alternative in IOL implantation in eyes with deficient capsules. The modifications in the existing technique decrease the learning time and risk for complications.

In vivo and in vitro study of suprachoroidal fibrin glue

PURPOSE

The suprachoroidal space is preferred for many reasons for implantation of retinal prostheses or drug delivery systems. This study aimed to investigate the safety and feasibility of suprachoroidal fibrin glue (FG), one of the adhesives used to fix the implanted material.

METHODS

Human retinal pigment epithelium cells (hRPE) were cultured with FG, assayed with 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, and studied by transmission electron microscopy. A total of 48 rabbits were randomly divided into three groups to undergo surgery: group 1, 0.1 ml suprachoroidal FG; group 2, 0.1 ml suprachoroidal normal saline (control); group 3, 0.1 ml intravitreal FG. Slit-lamp examination, indirect ophthalmoscopy, fundus photography, fundus fluorescein angiography (FFA), indocyanine green angiography (IA), electroretinography (ERG), and histopathological examination were performed at various time points till 90 days after injection.

RESULTS

No apoptosis changes of electron microscopy were observed in the hRPE cultured with FG, and the difference in the MTT test results was not statistically significant when compared with the control group (P>0.2). One day after suprachoroidal injection, slight choroidal hemorrhage occurred. No severe intraocular reactions were observed in any of the three groups, and FFA and IA showed no edema or leakage around blood vessels. There was no significant difference in latency or amplitude of the ERG wave among the three groups (P>0.1). Histopathological examinations showed the suprachoroidal FG induced localized inflammation (from acute inflammation to chronic phagocytosis) at the early stage and finally turned into fibrosis tissue.

CONCLUSIONS

FG is feasible for suprachoroidal use, and no obvious toxic reaction was observed in either in vitro or in vivo studies.

Fibrin sealant in corneal stem cell transplantation

PURPOSE

To determine if transplanted corneal epithelial stem cells are safely and efficiently attached to the deficient limbal niche with use of fibrin sealant. The primary outcome is measured with respect to the stability of the transplant, with secondary qualitative evaluations of inflammation, patient comfort, speed of operation, and incidence of complications.

METHODS

This retrospective case study examined a total of 114 corneal stem cell reconstructions performed in 95 patients from 1996 to 2004 using corneal stem cells primarily, with a minority of amnion alone, or both. Fibrin sealant was used as the only technique of stem cell adhesion for limbal reconstruction for primary or recurrent pterygia and various stem cell-deficient diseases from 2000 to 2004.

RESULTS

The fibrin sealant group showed 1 small recurrence of pterygium but no complications. With sutures, there were 3 recurrences in the pterygia group. After completion of all surgical procedures, all patients were free of pterygia. Miscellaneous stem cell deficiencies were included to demonstrate that corneal stem cell transplants can be used in other corneal procedures in addition to pterygia.

CONCLUSIONS

Fibrin sealant alone effectively and safely attached corneal stem cell transplants to the limbal niche. The additional qualitative observations of a reduction in operation time, postoperative pain, and inflammation augurs for more extensive use of fibrin sealants in ophthalmology.

Fibrin glue for the prevention of epithelial ingrowth after laser in situ keratomileusis

We present 3 cases of recurrent epithelial ingrowth following laser in situ keratomileusis. All patients consented to flap lifting, epithelial ingrowth removal, and placement of fibrin glue (Tisseel(R) VH, Baxter) at the flap edges. Two of 3 eyes had no evidence of recurrent epithelial ingrowth within a relatively short follow-up. One eye that also had had radial keratotomy had a small nest of stable epithelial cells that had not progressed. Fibrin glue may be a useful adjunct to prevent recurrent epithelial ingrowth. There were no complications associated with its use.

Results of vitrectomy and the no-touch-technique using autologous adjuvants in macular hole treatment

BACKGROUND

Anatomic and functional results of macular holes using vitrectomy and platelet-concentrate (PC) or autologous whole blood (WB) were investigated without peeling any epiretinal membrane in order to minimize retinal trauma.

METHODS

44 patients with macular holes stage II, III and IV underwent a vitrectomy with removal of posterior cortical vitreous (in stage II and III) and C2F6 gas endotamponade. No peeling of any epiretinal membrane or the ILM was performed. In 14 patients autologous WB was injected and in 30 patients autologous PC. The mean follow-up time was 9.3 months.

RESULTS

An anatomic closure was observed in 36.4% of patients in the WB-group and in 93.9% of patients in the PC-group. SLO-microperimetry showed a reduction of absolute scotomas in 80% of the WB- and in 75% of the PC-group. In the WB-group 1 retinal detachment and 1 branch vein occlusion occurred; in the PC-group 3 retinal detachments, 1 central artery occlusion, 1 macular pucker, 1 cystoid macular edema, 1 late reopening and 1 secondary glaucoma were observed. In both groups no endophthalmitis occurred.

CONCLUSION

If autologous platelet concentrate is available, high anatomic success rates can be achieved without aggressive membrane removal, which may cause retinal damage. Autologous whole blood cannot be recommended as an alternative adjunct for the treatment of macular holes without membrane removal.

Effectiveness of apraclonidine 1% in preventing intraocular pressure rise following macular hole surgery

AIM

To determine the efficacy of apraclonidine hydrochloride 1% in preventing intraocular pressure (IOP) spikes following idiopathic macular hole (IMH) surgery with platelet adjunct and intraocular gas tamponade.

METHODS

This is a prospective, double masked, randomised study to compare apraclonidine hydrochloride 1%, an alpha(2) agonist, with a placebo in the prevention of IOP rises following macular hole surgery. Each patient was randomly selected to receive either the study drug or the placebo; one drop was instilled in the conjunctival sac 2 hours preoperatively and on completion of the procedure. IOP was measured at baseline and at 1, 3, 6, 24, 48 hours, and 2 weeks postoperatively. Blood pressure and heart rate were also recorded at baseline and at 3 and 24 hours postoperatively. Macular hole repair surgery was performed as standardised in the unit with a vitrectomy, platelet concentrate, and complete fill of the vitreous cavity with perfluoropropane gas (C(3)F(8)) at a concentration of 16%.

RESULTS

25 patients (26 eyes) were enrolled. 12 eyes received apraclonidine hydrochloride 1% (mean age 70.7; range 62-78 years) and 14 eyes received the placebo (mean age 70.0; range 57-81 years). At baseline evaluation the mean IOP was 15.6 mm Hg for the study group and 14.3 mm Hg for the placebo group. The mean postoperative IOP at 1 hour, 3 hours, 6 hours, and 24 hours was 10.6, 9.6, 8.2, and 14.0 mm Hg in the apraclonidine group. In the control group at the same time intervals the mean IOP was 23.4, 17.5, 19.2, and 24.7 mm Hg. These readings were statistically significant different: 1 hour (p=0.0001); 3 hours (p=0.0015); 6 hours (p<0.0001); and 24 hours (p=0.019), the readings at 48 hours and 2 weeks were not statistically significant different (p=0.15 and p=0.59). Only one of the patients in the study group had an IOP above 25 mm Hg at any time. In the control group an IOP above 25 mm Hg was found in seven patients (50%) at the 1 hour postoperative measurement. At 2 weeks the IOP was recorded below 25 mm Hg in all patients. No statistically significantly difference was noted between the two groups regarding the systolic or diastolic blood pressure values and the heart rate records. No local or systemic adverse reactions were observed.

CONCLUSIONS

Apraclonidine hydrochloride 1% appears to be an efficacious and safe drug in the prophylaxis of early postoperative IOP elevations in patients undergoing macular hole surgery.

The macular hole: report of an Australian surgical series and meta-analysis of the literature

PURPOSE

To report an Australian series of macular hole surgery by pars plana vitrectomy and fluid-gas exchange, and to identify factors influencing the outcome of the surgery through meta-analysis of the literature.

METHODS

Fifty-six consecutive cases of macular hole were treated by pars plana vitrectomy, fluid-gas exchange and face-down positioning for at least 7 days, and prospectively followed for 3-12 months. Thirty-six reports of macular hole surgery were reviewed. A meta-analysis on the pre- and postoperative parameters was performed on 389 cases, in which case-specific data-points were available.

RESULTS

In the current series, anatomical closure was achieved in all (100%) of 16 stage 2, and in 35 (87.5%) of 40 stage 3 or 4 macular holes. At least 2 logMAR lines of improvement in visual acuity were seen in 10 (62.5%) stage 2 and 20 (50.0%) stage 3 or 4 holes. Postoperative visual acuity was 6/12 or better in 10 (62.5%) stage 2 and 17 (42.5%) stage 3 or 4 holes. In both the current series and the meta-analysis, favourable surgical outcomes were associated with stage 2 macular holes, better preoperative visual acuity, and shorter preoperative duration. Adjuvant use was associated with a higher rate of anatomical closure but there was no clear benefit in terms of postoperative visual acuity.

CONCLUSION

Our experience and the results of the meta-analysis suggest that macular hole surgery should be offered as early as possible once full-thickness neuroretinal defect occurs.

Internal limiting membrane removal in the management of full-thickness macular holes

PURPOSE

To determine the effectiveness of removal of the internal limiting membrane in the treatment of full-thickness macular holes.

METHODS

Data were reviewed from a prospective study on 47 consecutive eyes with full-thickness macular holes undergoing vitrectomy, internal limiting membrane maculorhexis, and fluid-gas exchange. No eye underwent repeat macular hole surgery. A meta-analysis was performed to compare the outcomes of different surgical techniques in the treatment of full-thickness macular holes.

RESULTS

The outcome measures were disappearance of the submacular fluid and the change in best-corrected visual acuity. The surgery was anatomically successful in 44 of the 46 eyes (96%) and 39 of the eyes (85%) showed an improvement of at least two Snellen lines. Best-corrected final vision was 20/40 in 18 (39%) eyes. No permanent complications specifically caused by the removal of the macular internal limiting membrane were detected; the minor hemorrhages and retinal edema seen in most eyes resolved spontaneously. Retinal detachment developed and was successfully treated in three eyes (7%). A meta-analysis on 1,654 eyes from published reports showed that internal limiting membrane maculorhexis appears to significantly (P <.0001) increase the anatomical and functional success rates in macular hole surgery.

CONCLUSIONS

Internal limiting membrane removal is an important development in the evolving field of macular hole surgery. A randomized, prospective, multicenter clinical trial should be performed to determine which surgical technique is the most beneficial in patients with full-thickness macular holes.

Intraoperative adjunctive agents in vitrectomy: serum, cytokines, and glue

The surgical goal in the treatment of retinal breaks is to seal the edges of the break, and traditionally, photocoagulation and cryocoagulation have been used to accomplish this. However, it is sometimes difficult in complicated retinal detachments to maintain the seal against tractional forces. Adhesion is achieved through a process of cell necrosis, inflammation and subsequent fibrovascular proliferation. This strategy, however, may not be appropriate in vision-sensitive areas such as macular holes. To improve the success rate of macular hole surgery, a number of authors have advocated the use of biological modifiers, such as transforming growth factor beta, human autologous serum, tissue glue, or platelet concentrates. These materials may enhance the adhesion of the detached retina and therefore lead to a better anatomical and functional success. We have reviewed the advances of intraoperative application of synthetic or biological adhesives. However, through the improvement of surgical techniques and surgeons' skills in recent years, the anatomical success rate of macular hole surgery has increased in most institutions without adjunctive additives. Thus, many surgeons believe that adjunctive additives may not be necessary for most idiopathic macular holes.

Effect of autologous platelet concentrate in surgery for idiopathic macular hole: results of a multicenter, double-masked, randomized trial. Platelets in Macular Hole Surgery Group

OBJECTIVE

To evaluate prospectively the efficacy and safety of autologous platelet concentrate (APC) as an adjuvant in surgery for idiopathic macular hole.

DESIGN

Multicenter, double-masked, randomized clinical trial.

SETTING

Four university-based ophthalmology clinics.

PARTICIPANTS

One hundred ten patients with stage 3 or 4 idiopathic full-thickness macular holes of less than 3 years' duration were randomized (53 eyes to the platelet group and 57 eyes to the control group).

INTERVENTIONS

Standardized macular hole surgery versus surgery combined with injection of an APC. In all cases, the procedure consisted of three-port pars plana vitrectomy, posterior hyaloid separation, and nonexpansile fluid-gas exchange. After the fluid-gas exchange, patients were randomized to receive either injection of an APC or no adjunctive treatment. After surgery, patients were positioned face down for 12 days. Platelet counts showed that the concentrates contained a mean of 96.106 platelets (range, 82-102).

MAIN OUTCOME MEASURES

Anatomic and functional evaluations were performed at 1, 3, and 6 months after surgery in a double-masked fashion by an independent observer. The main outcome was reapposition of the edge of the macular hole 1 month after surgery. Secondary outcomes were anatomic status at 3 and 6 months, changes in Early Treatment Diabetic Retinopathy Study score, and complications.

RESULTS

One month after surgery, the anatomic success rate in the platelet group was 52 of 53 (98%; 95% confidence interval, 0.90-1.00) versus 47 of 57 (82%; 95% confidence interval, 0.70-0.91) in the control group (P = 0.009, Fisher's exact test; relative risk, 0.11; 95% confidence interval, 0.01-0.81). Visual acuity was not significantly different between the two groups at any timepoint. There were no complications specifically attributable to the platelet injection.

CONCLUSION

Injection of APC improved significantly the anatomic success rate of surgery for idiopathic macular holes of less than 3 years' duration, but postoperative visual acuity of the platelet group was not statistically different from the control group.

Preparation of autologous platelets for the ophthalmologic treatment of macular holes

BACKGROUND

Platelet concentrates were recently used for ophthalmologic treatment of macular holes. This strategy was investigated to define standardized blood bank components.

STUDY DESIGN AND METHODS

Two different, highly concentrated autologous platelet components, one from whole-blood preparation and the other from plateletpheresis, were evaluated. In the first procedure, platelet-rich plasma was obtained from 250 mL of whole blood. After storage for 20 hours, platelet-rich plasma was concentrated in a second centrifugation step and adjusted to 10 x 10(9) platelets per mL. In the second procedure, platelets were collected by apheresis, stored overnight, centrifuged, and adjusted to 20 x 10(9) platelets per mL. The respective component was instilled during vitrectomy and gas tamponade in patients with stage II to IV macular holes. Patients were followed for 9 months.

RESULTS

With regard to the various preparation procedures and final concentrations of platelets in the components, no differences in wound healing were observed. An anatomic closure of the macular hole was achieved in 18 of 19 treated patients. Visual acuity improved in 14 patients.

CONCLUSION

Both types of highly concentrated platelet components were effective in achieving high closure rates of macular holes. These autologous platelet components possess the quality standard of blood bank components and could be of great benefit for initiating wound healing in other clinical settings.

Treatment of reopened macular hole after vitrectomy by laser and outpatient fluid-gas exchange

OBJECTIVE

This study aimed to assess a new nonsurgical treatment for patients who have previously undergone vitrectomy for macular hole with either persistent or reopened holes.

DESIGN

A prospective, noncomparative, consecutive case series.

PARTICIPANTS

Fifteen patients (15 eyes) were studied.

INTERVENTION

Patients were treated by an outpatient method consisting of laser photocoagulation to the foveal pigment epithelium followed by fluid-gas exchange with 20% perfluoropropane gas and prone positioning. Patients without known allergy were treated with two doses of oral Diamox (250 mg) and ciprofloxacin (500 mg).

MAIN OUTCOME MEASURES

Visual acuity, intraocular pressure, anatomic status of the macular hole, and cataract were the principal outcome measures studied.

RESULTS

Thirteen of 15 macular holes were closed successfully with 1 or more procedures. All patients with macular hole closure achieved two lines or greater of vision improvement on Snellen testing. Three patients (20%) achieved 20/40 and nine (60%) achieved 20/80 or better. Three patients required more than one procedure. Four patients developed mild transient ocular hypertension.

CONCLUSIONS

The combination of office-based outpatient fluid-gas exchange and laser appears to be a safe and cost-effective alternative to repeat surgery in selected patients with persistent or reopened macular holes after vitrectomy, in whom there are no visible epiretinal membranes, or in whom return to the operating room is undesirable for medical or personal reasons.

Pearls in the management of macular holes

We studied the efficacy of removing the retinal pigment epithelium (RPE) from the base of the macular hole to treat 124 eyes of 118 patients with stage 2 (n = 38), stage 3 (n = 52), or stage 4 (n = 34) macular hole. The patients ranged in age from 42 to 81 years (mean = 66.7 years), and the duration of symptoms preoperatively ranged from 1 to 140 months (average = 16.8 months). During vitrectomy for the macular hole, the RPE at the base of the hole was gently aspirated with either a silicone-tipped extrusion needle or a blunt-tipped 27-gauge needle. The follow-up period averaged 18.6 months (range = 3 to 48 months). The holes resolved in 112 (90%) of the 124 eyes after one surgical procedure. In 107 eyes with a follow-up period of 6 months or longer, 91 (85.0%) showed improved visual acuity of at least 2 lines of Snellen equivalent. The final visual acuity was 20/25 or better in 34 (31.8%) and 20/40 or better in 80 (74.8%) of the 107 eyes. A complication peculiar to RPE removal is the hypertrophy of the RPE. This complication was observed in 15 (14.0%) of the 107 eyes that were followed for 6 months or longer. From these results, I conclude that RPE removal will improve the anatomical and the visual results in selected macular hole cases.

Focal macular electroretinograms before and after successful macular hole surgery

PURPOSE

To report changes in focal macular electroretinograms before and after successful macular hole surgery and to discuss whether preoperative retinal function can predict postoperative visual acuity.

METHODS

In this prospective study, 28 consecutive eyes of 28 patients underwent vitrectomy for stage 2 or 3 full-thickness idiopathic macular hole. Focal macular electroretinograms using a 4-degree stimulus spot were obtained in 24 eyes of 28 patients, and those using a 5-degree stimulus spot were obtained in 24 eyes of 28 patients, to evaluate preoperative and postoperative amplitude and implicit time of the b-wave. Visual acuity was measured preoperatively and postoperatively, and results were translated into logMAR (minimum angle of resolution) values.

RESULTS

After successful macular hole closure, the b-wave amplitude increased in 23 of 24 eyes measured with the 4-degree stimulus spot and in 19 of 24 eyes measured with the 5-degree stimulus spot. Postoperative b-wave amplitude recorded with either stimulus spot correlated with postoperative corrected visual acuity. The b-wave implicit time decreased in 15 of 20 eyes measured with the 4-degree spot and in 13 of 23 eyes measured with the 5-degree spot. Preoperative b-wave implicit time measured with the 5-degree stimulus spot correlated significantly (P = .001) with postoperative corrected visual acuity.

CONCLUSIONS

Qualitative change (implicit time) is more important than quantitative change (amplitude) in electroretinograms for predicting postoperative corrected visual acuity. The function of the retinal tissue surrounding the hole may affect visual outcome.

Glaucoma after macular hole surgery

OBJECTIVE

The study aimed to report incidence and to assess risk factors of postoperative glaucoma in patients with stage 3 idiopathic macular hole treated with pars plana vitrectomy, removal of posterior hyaloid membrane, and perfluoropropane gas tamponade.

DESIGN

The author performed a retrospective chart review and statistical analysis of risk factors of postoperative glaucoma by using chi-square statistics, Fisher's exact test, and logistic regression.

PARTICIPANTS

Forty consecutive patients with stage 3 idiopathic macular hole who were operated on between January 1994 and December 1995 were studied.

INTERVENTION

A pars plana vitrectomy, removal of posterior hyaloid membrane, and 14% perfluoropropane gas tamponade were done to all patients.

MAIN OUTCOME MEASURES

Preoperative and postoperative intraocular pressure measurements were performed.

RESULTS

Twenty-one (52%) of 40 patients experienced transient intraocular pressure elevation to more than 30 mmHg. Nine (22%) had pressure elevation within 2 to 4 hours, 6 (15%) in 24 hours, and 6 (15%) in 1 week after surgery. Three patients, including one with a history of preoperative ocular hypertension, required extended topical antiglaucoma medication. Factors of age, race, gender, lens status, preoperative intraocular pressure (all preoperative intraocular pressure were 25 mmHg or less), and success in closure of macular hole were not to any statistically significant degree associated with postoperative pressure elevation.

CONCLUSION

Glaucoma is a significant complication after stage 3 macular hole surgery even without adjunctive therapy. Usually happening within the first postoperative week, elevation of intraocular pressure in most cases is transient and can be controlled by medication. However, extended medication might become necessary in some cases.

Surgical closure of macular hole using an absorbable macular plug

BACKGROUND

The surgical management of macular holes has been a subject of controversy in recent years. Various techniques such as vitrectomy, membrane peeling, and gas tamponade with or without transforming growth factor-beta 2, and recently the use of autologous platelets have produced closure rates from 58% to 96%, depending on the stage of the hole.

METHODS

The authors present preliminary results in a study of 19 consecutive patients with stage 3 or stage 4 macular hole who underwent vitrectomy followed by placement of an absorbable partially cross-linked gelatin plug in the macular hole. The vitreous cavity was filled with a nonexpanding gas or air alone; the patient was instructed to maintain prone positioning for 2-3 days.

RESULTS

Anatomic attachment of the edges of the macular hole was achieved in 19 out of 19 patients with a minimum follow-up period of 6 months (average 11.5 months).

CONCLUSIONS

A cross-linked gelatin plug can effectively reattach the edges of macular holes of stages 3 and 4. Its use is recommended only in macular holes in high myopes with posterior staphyloma or recurrent macular hole.

Outpatient postoperative fluid-gas exchange after early failed vitrectomy surgery for macular hole

BACKGROUND

Vitrectomy surgery with fluid-gas exchange and prone positioning has been shown to close macular holes and improve vision. In those eyes that have failed surgery, repeat vitrectomy has been advocated. As an alternative, the authors performed an outpatient postoperative fluid-gas exchange on eyes when the macular hole failed to close after vitrectomy surgery.

METHODS

The authors reviewed all cases of failed vitrectomy surgery for macular holes that underwent a postoperative fluid-gas exchange. Eyes were considered to have failed initial surgery if a rim of subretinal fluid surrounded an open full-thickness macular hole.

RESULTS

Twenty-three consecutive eyes underwent outpatient fluid-gas exchange 1 week to 8 weeks after vitrectomy surgery. In 17 eyes (74%), fluid-gas exchange resulted in flattening and closure of the macular hole. In all 17 eyes, visual acuity improved 2 or more lines, with 8 (35%) of the 23 eyes achieving 20/50 or better visual acuity.

CONCLUSIONS

Postoperative fluid-gas exchange may achieve successful closure of macular holes and improve vision in eyes that have failed surgery for full-thickness macular holes and should be considered as a cost-effective alternative to repeat vitrectomy.