Sutureless vitrectomy

EVALUATION OF PRONE VERSUS SUPINE POSITIONING IN FRESH RHEGMATOGENOUS RETINAL DETACHMENT TREATED WITH PARS PLANA VITRECTOMY AND GAS

PURPOSE

To compare Supine versus Prone positioning in fresh rhegmatogenous retinal detachments treated with vitrectomy and gas tamponade.

METHODS

This was a prospective randomized controlled trial of 72 eyes with fresh rhegmatogenous retinal detachment that underwent 25-gauge vitrectomy: 37 eyes were allotted supine position and 35 were allotted prone position. Cases were evaluated for single-surgery reattachment rates, best-corrected visual acuity, intraocular pressure, cataract formation, and any complications. The patients were followed up for a period of 3 months.

RESULTS

Both groups had similar demographics, and no significant difference was found between the two groups in terms of extent of retinal detachment, position, and number of breaks. The anatomical success after single surgery was 97.3% in the Supine group and 94.3% in the Prone group ( P = 0.609). The best-corrected visual acuity at the end of 3 months was 0.44 ± 0.27 in the Supine group and 0.35 ± 0.27 in the Prone group ( P = 0.119) with a significant increase in best-corrected visual acuity preoperatively from 0.11 ± 0.22 and 0.13 ± 0.22 in Supine and Prone groups, respectively ( P = <0.001). The intraocular pressure in the two groups was comparable at each follow-up. The rates of cataract formation were also similar in the two groups-60% and 53.8% in Supine and Prone groups, respectively ( P = 1.00). Complications such as spikes in intraocular pressure, epiretinal membrane formation, and cystoid macular edema were similar in both groups.

CONCLUSION

Rates of retinal reattachment were comparable in both groups showing that supine position is equally safe and effective for adequate tamponade.

Small-Gauge Vitrectomy for Macular Surgery Using a Systematic Approach to Wound Closure: 27-Gauge vs 25-Gauge

Purpose: To evaluate the effectiveness of and to compare vitrectomy performed with 25-gauge or 27-gauge instrumentation for macular surgery by assessing the surgical duration, wound closure, and complication rate using a systematic approach to wound closure. Methods: In this retrospective chart review, 125 25-gauge and 125 27-gauge consecutive small-gauge vitrectomy surgeries for epiretinal membrane, macular hole, vitreomacular adhesion, or a combination were analyzed during and immediately after surgery. Wound closure was performed using a systematic protocol. Results: Baseline characteristics were not statistically different between the 2 groups. The surgical duration was similar with 25-gauge vitrectomy and 27-gauge vitrectomy (P = .07). Although spontaneous wound closure was common in both groups, it was more common in the 27-gauge group (P = .22). Intraoperative and postoperative complications were uncommon in both groups. Conclusions: Findings show that 27-gauge vitrectomy is a safe, effective alternative to the more commonly used 25-gauge vitrectomy for macular surgery. Less manipulation was required to achieve wound closure with 27-gauge vitrectomy using a standardized wound-closure protocol. Smaller 27-gauge vitrectomy did not increase surgical time or complications over 25-gauge vitrectomy for macular surgery.

Optic inversion of scleral-fixated intraocular lens after vitrectomy with fluid-air exchange: case series and review of the literature

Lens dislocation is a significant complication after cataract surgery. Scleral fixation of 3-piece intraocular lens provides favorable visual outcome and can spare patients the need for lens exchange. Two patients presented with dislocated 3-piece lenses implanted over 10 years earlier. Both patients underwent pars plana vitrectomy and dropped lens rescue with scleral fixation. Postoperatively, the lens optic was found flipped nearly 90° at the optic-haptic junctions secondary to fluid-air exchange performed during vitrectomy. Both patients underwent intraocular lens exchange with a four point sclera fixated lens. Our study found that air tamponade is better avoided during rescue of old dislocated 3-piece lens implants. Intraocular lens exchange is preferred, when possible, to avoid complications associated with old dislocated lenses. Larger studies are needed to determine the effect of time on dislocated lens implants materials.

A Rare Complication Causing Another Rare Complication: Corneal Dellen with Infiltration Secondary to Subconjunctival Silicon Oil

The usage of silicon oil (SO) in vitreoretinal surgery is associated with potential complications. One such complication is the extravasation of SO into the subconjunctival space through open sclerotomies. Subconjunctival SO (SCSO) can cause irregularities in the ocular surface which predisposes to complications like corneal dellen. This corneal dellen can get infected in rare situations. SCSO needs to be removed to stabilize the ocular surface. We present a case of corneal dellen with infiltration which developed as a consequence of SCSO and its management.

Vitrectomy and ILM peeling in rhesus macaque: pitfalls and tips for success

BACKGROUND

The non-human primate (NHP) model is ideal for pre-clinical testing of novel therapies for human retinal diseases due to its similarity to the human visual system. However, intra-ocular delivery of gene therapy or cell transplantation to the retina gets hampered by the sticky vitreous body and poorly permeable inner limiting membrane (ILM) in primates. Although vitrectomy and ILM peeling are commonly performed in patients, many pitfalls exist in carrying out these procedures in the rhesus macaque, which have not been reported previously.

METHODS

We summarised common surgical pitfalls after performing vitrectomy and ILM peeling in four eyes of two rhesus macaques (one male and one female). We provided corresponding hands-on technical tips based on our surgical experience and literature search. Orbital CT scans were compared between adult rhesus macaques and humans. High-resolution surgical videos were recorded to demonstrate each critical surgical step.

RESULTS

Due to size difference, poor post-operative compliance, and high-standard requirements of a controlled experiment, there were eleven common surgical pitfalls during vitrectomy and ILM peeling in rhesus macaque. Falling into these pitfalls may produce discomfort, add fatigue, cause surgical complications, or even lead to the exclusion of the NHP from an experimental group.

CONCLUSION

Recognition and circumvention of these pitfalls during vitrectomy and ILM peeling in NHP are essential. By focusing on these surgical pitfalls, we can better carry out preclinical tests of novel therapies for retinal diseases in the NHP model.

Mechanical Property Comparison of 23-, 25-, and 27-Gauge Vitrectors across Vitrectomy Systems

OBJECTIVE

To investigate the mechanical properties of 23-, 25-, and 27-gauge vitrectomy vitrectors across 3 different vitrectomy systems to inform surgical techniques.

DESIGN

An experimental study that did not involve any human subjects.

METHODS

Nine vitrectors (3 each of 23-, 25-, and 27 gauge) from Alcon, Dutch Ophthalmic Research Center (DORC), and Bausch & Lomb (B/L) were measured. Measurements were performed using electroforce displacement at the tip and 15 mm from the tip. Five measurements were performed at each location, and fully elastic deformation was ensured.

MAIN OUTCOME MEASURES

The main parameter being measured was the force in grams (gf) necessary to deflect the vitrectors vertically downward by 1 mm, either at the tip of the vitrector or 15 mm from the tip.

RESULTS

A total of 90 measurements were performed. Across brands, B/L demonstrated the least stiffness at both the tip and at the 15-mm point for 23-gauge (8.0±0.3gf, 67.3±1.0gf), 25-gauge (6.8±0.3gf, 60.5±0.4gf), and 27-gauge (3.3±0.1gf, 33.9±0.5gf) vitrectors. Although there was only a small decrease in the stiffness in the 25-gauge vitrector compared with the 23-gauge vitrector at the 15-mm point, this difference was statistically significant for Alcon (P < 0.001), DORC (P < 0.001), and B/L (P < 0.001).

CONCLUSIONS

Based on this study, 25-gauge vitrectors, although larger than the 27-gauge vitrectors and less stiff than the 23-gauge vitrectors, may offer favorable compromise between stiffness and gauge size. However, surgeon experience, preference, and the type of surgery being performed should be paramount when making the final vitrector selection. Knowledge of these mechanical properties may aid surgeons in choosing between gauge size and vitrectomy system to optimize their comfort and efficiency.

Dellen formation as a complication of subconjunctival silicone oil following microincision vitrectomy

Purpose

To study the subconjunctival silicone oil (SCSO) parameters associated with dellen formation following microincision vitrectomy (MIV).

Patients and methods

This was a case-control study of 20 eyes with SCSO following MIV. Ten of them suffered postoperative dellen formation. Dellen occurrence, their sizes, number of loci, and distance between SCSO and the limbus were recorded. The outcome after silicone-oil removal was evaluated.

Results

The SCSO was at 3.1±1.2 mm from the limbus. All cases with dellen had SCSO within 2 mm of the limbus (P<0.001). No other factors were found to be associated with dellen formation (age, P=0.414; sex, P=0.656; laterality, P=1; indication for pars plana vitrectomy, P=0.655; instrument gauge, P=0.211; circumference involved by SCSO, P=0.252). All the dellen healed after surgical evacuation of SCSO (P<0.001), leaving scars.

Conclusion

Dellen can be associated with MIV secondary to SCSO near the limbus. Resolution with scarring occurred following SCSO evacuation. Therefore, SCSO should be evacuated as early as possible to avoid long-term peripheral corneal morbidity.

Different techniques of transconjunctival cannulated vitrectomy versus conventional non-cannulated vitrectomy in various vitreoretinal disorders

Purpose

To evaluate the safety and efficacy of different methods of transconjunctival cannulated vitrectomy versus conventional non-cannulated vitrectomy in various vitreoretinal disorders.

Methods

A prospective randomized study was done from August 2009 to February 2011. The study included 129 eyes of 122 patients, randomly divided into four groups. Group 1 comprised 34 eyes operated on using transconjunctival 20-gauge cannula Claes system. Group 2 comprised 32 eyes operated on using transconjunctival cannulated 23 gauge system. Group 3 comprised 27 eyes operated on using combined 20-gauge non-cannulated and 23-gauge transconjunctival cannulated system. Group 4 comprised 36 eyes operated on using conventional non-cannulated 20-gauge system.

Results

The four groups were demographically similar. Anatomical outcome was achieved in all cases. Vision was improved in 29 eyes (85.3%) in group 1, 23 eyes (71.9%) in group 2, 19 eyes (70.4%) in group 3, and 26 eyes (72.2%) in group 4. There was no statistical difference between the four groups 1-day postoperative (P=0.405) and 1-week postoperative intraocular pressure (P=0.254). The number of sutureless sclerotomies was 68 (66.6%) in group 1, 78 (81.3%) in group 2, 50 (61.8%) in group 3, and 0 in group 4. Hypotony occurred in one eye (2.9%) in group 1, three eyes (9.4%) in group 2, two eyes (7.4%) in group 3, and no eyes in group 4. Operative endophthalmitis did not occur in any one of the four groups.

Conclusion

Final anatomical and functional outcomes were not related to the type of sclerotomy used (cannulated or non-cannulated), the gauge used (20 or 23), the route (transconjunctival or transscleral), or type of suture used. The advantages of small-gauge transconjunctival vitrectomy were patient comfort, early ambulation, and preservation of the conjunctiva. This should be weighed against the cost of this cannula system.

Small-gauge vitrectomy does not protect against nuclear sclerotic cataract

PURPOSE

To determine whether the gauge of vitrectomy instrumentation is associated with the progression of nuclear sclerotic cataract.

METHODS

A prospective interventional and observational study of patients undergoing vitrectomy surgery for various retinal conditions. Patients had Scheimpflug lens photography in the operated and fellow eye at baseline and at 6 months and 12 months after vitrectomy surgery.

RESULTS

Of 42 eyes included in the analysis, 11 had 20-gauge surgery, 22 had 23-gauge surgery, and 9 had 25-gauge surgery. In all operated eyes, vitrectomy surgery led to the significant progression of nuclear sclerotic cataract, compared with the fellow, unoperated eye. This small study was unable to detect a difference in nuclear sclerotic progression when comparing small-gauge surgery (23 and 25 gauge) with standard 20-gauge surgery.

CONCLUSION

Removal of the vitreous gel using any-gauge vitrectomy surgery leads to significant progression of nuclear sclerotic cataract at 6 months and 12 months. The findings are consistent with the hypothesis that the vitreous gel is important in protecting the lens from increased exposure to oxygen that leads to the formation of nuclear sclerotic cataract. This increased exposure to oxygen occurs as a result of removing the vitreous gel and is independent of the gauge of vitrectomy instrumentation.

Conjunctival pigmentation after 23-gauge microincisional vitrectomy surgery

AIM

To investigate cases with conjunctival pigmentation originating from sclerotomy sites after 23-gauge microincisional vitrectomy surgery (MIVS).

METHODS

This is a retrospective study comprised of 185 eyes from 185 consecutive patients who underwent 23-gauge MIVS. The authors investigated the incidence and the clinical factors associated with conjunctival pigmentation, including indication of vitrectomy and surgical procedures.

RESULTS

Eight eyes (4.3%) from 185 eyes showed conjunctival pigmentation after surgery within 7 days postoperatively. Light microscopic examination of excised tissue showed infiltration of abundant dark brownish colored melanophages with surrounding scattered, finely granular, melanin pigments. C3F8 gas tamponade (OR, 9.4; 95% CI, 1.9-44.5; P=0.005) was significantly associated with conjunctival pigmentation. The mean surface area (21.26±2.21 mm(2)) of three eyes with C3F8 tamponade was significantly larger than that of five eyes (2.51±0.73 mm(2)) without tamponade (P=0.025). Neither leakage nor hypotony was found.

CONCLUSIONS

Intraocular melanin pigments could prolapse through the sclerotomy site and cause conjunctival pigmentation after 23-gauge MIVS. Thus, preoperative warning is necessary in patients with 23-gauge MIVS.

23-gauge transconjunctival sutureless vitrectomy: visual outcomes and complications

PURPOSE

To report results and complications of 23-gauge transconjunctival sutureless pars plana vitrectomy for a variety of vitreoretinal diseases.

METHODS

A prospective consecutive case series study was performed in 66 eyes of 66 patients. Indications for surgery were epiretinal membrane (n = 20), rhegmatogenous retinal detachment (n = 19: 14 pseudophakic, 5 phakic), macular hole (n = 16), vitreous hemorrhage (n = 5), cyclodialysis (n = 1), intraocular lens luxation (n = 1), asteroid hyalosis (n = 1), congenital retinoschisis (n = 1), and endophtalmitis (n = 2). Main outcome measures included visual acuity, intraocular pressure, and intra- and post-operative complications.

RESULTS

Mean patient age at time of operation was 68 ± 12 years. Overall, visual acuity improved from 1.03 ± 1.00 logMAR preoperatively to 0.32 ± 0.33 logMAR postoperatively (p < 0.01) after a mean follow-up time of 9.3 ± 4.7 months. Mean preoperative intraocular pressure was 13.9 ± 3.5 mmHg, and mean postoperative intraocular pressure was 17.9 ± 9.6 mmHg on day 1 (p < 0.01) and 14.7 ± 2.8 mmHg (p = 0.05) at final visit. Concerning complications, 2 cases of hypotony and 7 of hypertony occurred on day 1, a macular hole reopened some weeks later, and a retinal detachment recurred in one case.

CONCLUSION

23-gauge transconjunctival sutureless vitrectomy is an effective and safe technique for a variety of vitreoretinal diseases.

Endophthalmitis in the era of small gauge transconjunctival sutureless vitrectomy--meta analysis and review of literature

PURPOSE

The goal of this study was to review, evaluate, and perform a meta-analysis on the current literature that reports rates of postoperative endophthalmitis after small gauge transconjunctival sutureless vitrectomy (TSV) and compare it to 20-gauge pars plana vitrectomy (20G PPV).

METHODS

We performed an extensive review of the current literature. We included only large comparative institutional reviews. Meta-analysis of these reviews was performed.

RESULTS

We found six large retrospective comparative cases series on the 25-gauge (25G) TSV as compared to 20G PPV. The test for homogeneity for the meta-analysis indicates that the studies are not homogeneous and therefore the evidence is tentative.

CONCLUSION

We cannot conclude that 25G TSV has a higher rate of postoperative endophthalmitis compared to the 20G PPV. Future retrospective or prospective trials need to take into consideration multiple factors.

Presumed sclerotomy site bleeding inflowing into the anterior chamber after the removal of a 23-gauge microcannula in 23-gauge sutureless vitrectomy

We experienced two cases of the influx of the sclerotomy site bleeding into the anterior chamber during 23-gauge sutureless vitrectomy for pseudophakic rhegmatogenous retinal detachment. Soon after the removal of a 23-gauge microcannula at the end of the surgery, presumed sclerotomy site hemorrhage was rapidly fluxed into the anterior chamber. The anterior chamber bleeding might come from the sclerotomies rather than from episcleral vessels. The posterior pressure in the gas-filled pseudophakic eye might have pushed the sclerotomy site bleeding into the anterior chamber. We could not find any vitreous hemorrhages. The hemorrhage within the anterior chamber spontaneously absorbed within 14 days.

Polyethylene glycol hydrogel polymer sealant for closure of sutureless sclerotomies: a histologic study

PURPOSE

To evaluate a polyethylene glycol-based hydrogel bandage for its ability to secure sutureless pars plana vitrectomy sclerotomies.

DESIGN

Laboratory investigation.

METHODS

Twenty-gauge (20-G) and twenty-three gauge (23-G) sclerotomies were constructed in human cadaveric eyes. A total of 24 sclerotomies were constructed in 6 eyes. Four sclerotomies per eye were constructed. Two were straight 20-G incisions, of which 1 was sutured and 1 was covered with the bandage. The other 2 were 23-G beveled incisions, of which 1 was left bare and the other was closed with the hydrogel bandage. India ink was applied over the sclerotomy sites while the intraocular pressure (IOP) was varied. The presence of India ink particles along incisions was evaluated by histologic analysis.

RESULTS

The hydrogel bandage prevented the entry of ink particles in all covered incisions after IOP modulation and incision manipulation. One 20-G sutured incision showed partial ink ingress. Four uncovered 23-G incisions showed the presence of ink within the inner aspect of the incisions (P = .0455 relative to 23-G sealed incisions). Twenty-two out of 24 incisions were evaluated, as 2 incisions could not be identified on histologic analysis.

CONCLUSIONS

The use of a hydrogel bandage to close sutureless sclerotomies is a practical alternative to sutures. Closure of sutureless sclerotomies may reduce the entry of ocular surface fluid into these incisions as well as prevent leakage of intraocular fluid in the immediate postoperative period. Incision closure may reduce the incidence of postoperative endophthalmitis and hypotony in sutureless vitreous surgery.

Combination 20 and 23-gauge transconjunctival vitrectomy: a new approach

The advent of smaller gauge instrumentation allows for minimally invasive vitreoretinal surgery (MIVS) as compared to conventional pars plana vitrectomy. Sutureless posterior segment surgery has the advantages of faster wound healing, minimal surgical trauma, decreased convalescence period besides reduced postoperative astigmatism; however, slower gel removal and limited peripheral vitreous dissection are disadvantages with smaller gauge systems. We herein describe a new technique combining 23-gauge and 20-gauge vitrectomy to improve the effectiveness and outcomes of vitreoretinal surgery.

[Spontaneous scleral rupture revealed by hypotony maculopathy]

Cases of a spontaneous scleral rupture are very uncommon. Their diagnosis can be challenging because the scleral lesion might be invisible on clinical examination. We describe herein one case revealed by hypotony maculopathy. A 30-year-old woman presented with severe visual loss in one eye caused by sudden hypotony. Funduscopy revealed a chorioretinal coloboma in the periphery of the retina associated with a hypotony maculopathy. Extensive work-up included optical coherence tomography (OCT), fluoroangiography, ultrasonography, and magnetic resonance imaging examinations. A search for infectious and inflammatory diseases was conducted. Inflammatory and infectious work-ups were not contributive. A surgical exploration was performed, which showed a spontaneous scleral perforation within the coloboma. A patch of polytetrafluoroethylene was sutured on the damaged sclera and air was injected into the vitreous cavity. Vision and ocular pressure were rapidly restored. Spontaneous scleral rupture cases associated with hypotony and visual loss are rare, with only a few cases reported in the literature. Hypotony maculopathy with sclerochoroidal lesion may be the cause of such cases. Excellent outcome can be obtained with surgical diagnosis and repair.