27-gauge Microincision Vitrectomy Surgery Research Articles

Comparative Study of Corneal Wetting Agents During 25-Gauge Microincision Vitrectomy Surgery Under a Noncontact Wide-Angle Viewing System

To compare the effects of corneal wetting agents during 25-gauge microincision vitrectomy surgery (MIVS) under a binocular indirect ophthalmic microscope system. This prospective, randomized, comparative study included 45 eyes undergoing 25-gauge MIVS. The randomly assigned corneal wetting agents were balanced salt solution, ProVisc, and DisCoVisc. The main outcome measures were the frequency of applications, the duration of each application, and the corneal surface status including corneal fluorescein staining score postoperatively. The mean frequency of applications was higher for balanced salt solution (13.6 ± 4.3) than ProVisc (2.7 ± 1.0) or DisCoVisc (1.7 ± 0.5) (P < .001). The duration of each application was longer for DisCoVisc (29.8 ± 6.0 minutes) than balanced salt solution (3.7 ± 1.1 minutes) or ProVisc (17.6 ± 3.6 minutes) (P < .001). The fluorescein staining score was higher for balanced salt solution until 7 days postoperatively (P < .001). ProVisc and DisCoVisc could be more effective corneal wetting agents than balanced salt solution by minimizing the frequency of intraoperative application and postoperative corneal injury.

Comparative Evaluation of 23- and 25-Gauge Microincision Vitrectomy Surgery in Management of Diabetic Macular Traction Retinal Detachment

To compare the efficacy, outcomes, and complications of 23-G and 25-G microincision vitrectomy surgery (MIVS) in cases of diabetic tractional retinal detachment (TRD). This is a prospective, single-blinded, randomized, comparative study. Fifty eyes of 50 patients with diabetic TRD involving or threatening macula were randomized into 2 groups of 25 each. Group 1 underwent 23-G MIVS and group 2 underwent 25-G MIVS. Patients were followed up at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year after surgery. The primary outcome measure was anatomic and visual success after surgery. We also compared the 2 alternative MIVS systems and assessed various intraoperative and postoperative parameters. Anatomic achievement was achieved in all eyes and both groups showed a significant improvement in vision after surgery (p = 0.033 and p = 0.004, respectively) and were comparable (p = 0.584). Mean surgical time in 25-G surgery was significantly longer than in 23-G surgery by 4.60 minutes (p<0.001). Postoperative mean astigmatism was comparable in the 2 groups and postoperative hypotony was not encountered in either group. No port-related breaks were seen in either group; however, iatrogenic breaks occurred in 4 eyes in the 23-G group and 5 eyes in the 25-G group (p = 1.000). There was significantly less immediate postoperative pain and foreign body sensation in the 25-G group compared with the 23-G group. Both 23-G and 25-G MIVS have comparable visual and anatomic results for diabetic TRD; however, 25-G surgery may be associated with less postoperative pain and discomfort than 23-G surgery.

Combined 25-Gauge Microincision Vitrectomy and Toric Intraocular Lens Implantation With Posterior Capsulotomy

To evaluate the efficacy of combined 25-gauge microincision vitrectomy surgery (MIVS) and toric intraocular lens (IOL) implantation with posterior capsulotomy. Noncomparative, interventional case series performed at a single center. Twelve patients with vitreoretinal disease and cataracts, with preexisting regular corneal astigmatism greater than 1 diopter, underwent 25-gauge MIVS and toric IOL implantation with posterior capsulotomy. The toric IOL was successfully implanted in each case. At 6 months postoperatively, mean axis rotation was 5.7° ± 3.1°. At 1 month postoperatively, mean uncorrected and best corrected visual acuity improved; the improvement was maintained after 6 months. The absolute residual refractive cylinder was significantly lower postoperatively than the pre-existing regular corneal cylinder (P = .003). There were no surgical complications except temporary posterior iris synechiae in one case. Combined 25-gauge MIVS and toric IOL implantation with posterior capsulotomy is a practical and safe method to treat vitreoretinal disease and cataracts with pre-existing corneal astigmatism.

Efficacy of combined 25-gauge microincision vitrectomy, intraocular lens implantation, and posterior capsulotomy

To evaluate the efficacy of combined 25-gauge microincision vitrectomy surgery, intraocular lens (IOL) implantation, and posterior capsulotomy. Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan. Comparative case series. The medical records of eyes that had 25-gauge microincision vitrectomy and IOL implantation without posterior capsulotomy (June 2009 to May 2010) or with posterior capsulotomy (June 2010 to May 2011) were reviewed. Outcomes measured were corrected distance visual acuity (CDVA) at 1 and 6 months, the rate of neodymium:YAG (Nd:YAG) laser capsulotomies for postoperative posterior capsule opacification (PCO), and the rate of surgical complications. The records of 343 eyes were reviewed; 136 eyes did not have a posterior capsulotomy, and 207 eyes had a posterior capsulotomy. There was a significant difference in the rate of Nd:YAG capsulotomy between the no-capsulotomy group (18 eyes, 13.2%) and the capsulotomy group (2 eyes, 1.0%) (P<.01). The mean CDVA improved postoperatively in both groups (P<.01); in 20 patients with postoperative PCO, the mean CDVA improved after Nd:YAG capsulotomy (P<.05). Intraoperatively, gas leaked into the anterior chamber in 5 (6.3%) of 79 eyes in the capsulotomy group that required fluid-air exchange. Combined 25-gauge microincision vitrectomy, IOL implantation, and posterior capsulotomy was safe and reduced the need for postoperative Nd:YAG capsulotomy. Posterior capsulotomy should be performed with caution in eyes that are expected to require intraoperative fluid-air exchange.

Faster recovery after 25-gauge microincision vitrectomy surgery than after 20-gauge vitrectomy in patients with proliferative diabetic retinopathy

Background and methodsWe compared surgical procedures and outcomes, including duration of recovery period, in eyes with proliferative diabetic retinopathy that underwent 25-gauge microincision vitrectomy surgery with those that underwent 20-gauge vitrectomy. Seventy-two eyes from 53 patients that underwent 20-gauge vitrectomy in 2006 and 87 eyes from 55 patients that underwent 25-gauge vitrectomy in 2010 were studied. The surgical procedures, ie, number of vitreous procedures, operating time, and ratio of type of intraocular tamponade were compared between the two groups. In addition, the outcomes, ie, postoperative complications, anatomical success, postoperative best-corrected visual acuity (BCVA), and duration of hospitalization as an indicator of the postoperative recovery period were also compared.ResultsThere were no significant differences in surgical procedures or ratio of cases with postoperative complications between cases with 20-gauge and 25-gauge vitrectomy. The final anatomical success rate was 100% in the two groups. BCVA at 6 months after the final vitrectomy was significantly better than the preoperative BCVA for both types of vitrectomy (P < 0.05), and was not significantly different between the two groups. The average duration of hospitalization was 19.5 days after 20-gauge vitrectomy, which was significantly longer than the 11.0 days after 25-gauge vitrectomy (P < 0.001).ConclusionThese results indicate that the anatomical and functional improvements after 25-gauge microincision vitrectomy surgery are not significantly different from those after 20-gauge vitrectomy in eyes with proliferative diabetic retinopathy. However, the significantly shorter recovery period after 25-gauge microincision vitrectomy surgery suggests that it is less traumatic than 20-gauge vitrectomy.

Successful Outcomes of 25- and 23-Gauge Vitrectomies for Giant Retinal Tear Detachments

The authors examined the feasibility of performing 25- and 23-gauge micro-incision vitrectomy surgery (MIVS) for a giant retinal tear. The medical records of 12 eyes of 11 patients with giant retinal tear who underwent MIVS using perfluorocarbon liquids were reviewed. All patients were observed for at least 6 months postoperatively. An intraoperative re-attachment was achieved in 12 eyes (100%) and 11 eyes (92%) remained attached without intraocular tamponade. Silicone oil was used in 9 of 12 eyes and removed 2 weeks after the initial vitrectomy except in one eye. The postoperative retinal complications included macular pucker in two eyes, subretinal perfluorocarbon liquid in two eyes, retinal folds in one eye, cystoid macular edema in one eye, and redetachment due to proliferative vitreoretinopathy in one eye. Although the study had a short follow-up period, primary MIVS appears to be safe and feasible for giant retinal tear surgery.

Difficulty in Inserting 25- and 23-Gauge Trocar Cannula during Vitrectomy

Purpose: To determine the incidence of difficulty in inserting a 25- and 23-gauge trocar cannula (DITC) during 25- or 23-gauge micro-incision vitrectomy surgery (MIVS). Methods: Retrospective, consecutive, interventional case series performed by a single surgeon at a single centre. We defined a DITC as the condition where at least 1 trocar cannula could not be inserted into the vitreous at the beginning of MIVS. The incidence of DITC was calculated from 1,525 eyes, and the pre-operative demographics of the DITC cases were compared to those of the non-DITC cases. Results: The incidence of DITC for all cases was 0.6% (9 of 1,525 eyes). Overall, there were 242 eyes with a retinal detachment (RD), and 8 of the 9 eyes with DITC had an RD with an incidence of 3.3% (8 of 242 RD eyes). Seven of these 8 eyes had a total RD, 4 also had a choroidal detachment, 4 eyes were also myopic (>–8.0 dpt, high myopia), and 6 of the 8 eyes were hypotonic (<8 mm Hg). The DITC cases had larger RDs (p < 0.0001), a higher incidence of choroidal detachment (p < 0.0001), higher myopia (p = 0.0204) and hypotony (p = 0.0003) than the non-DITC eyes with an RD. Conclusions: A large RD, a choroidal detachment, high myopia and hypotony are significant risk factors for DITC. We recommend that MIVS should be performed cautiously for eyes with these risk factors.

Successful Removal of Large Intraocular Foreign Body by 25-Gauge Microincision Vitrectomy Surgery

We describe a new technique for removing a large intraocular foreign body by 25-gauge microincision vitrectomy surgery (25G-MIVS). Noncomparative interventional case series were performed at a single centre. Two patients with a long smooth intraocular vitreal foreign body underwent phacoemulsification and aspiration, intraocular lens implantation, 25G-MIVS, and extraction of the foreign body. The foreign body was removed through a posterior capsulorhexis, anterior continuous curvilinear capsulorhexis, and a corneal incision. In both cases, the foreign body was safely removed through the corneal incision, and IOL was implanted and well positioned. The surgical incision did not require suturing. No postoperative complications associated with this technique were found. The corneal endothelial cell density was maintained over 2000 cells/mm2 in both cases during recent follow-up examinations. Our findings indicate that 25G-MIVS with this technique can be used to extract a long slender smooth foreign body. It is safe, without complications, and can be performed without enlarging the 25-gauge sclerotomy.

Bacterial Contamination of the Vitreous Cavity Associated with Transconjunctival 25-Gauge Microincision Vitrectomy Surgery

To evaluate differences in the bacterial contamination rates of the vitreous cavity between patients undergoing transconjunctival 25-gauge microincision vitrectomy surgery (MIVS) and conventional 20-gauge pars plana vitrectomy (PPV). Prospective, comparative, consecutive, interventional case series. Eighty-one eyes of 81 patients who underwent primary vitrectomy and completed perioperative sample collection. Patients were randomly assigned to 25-gauge MIVS or 20-gauge PPV. Conjunctival swabs were obtained from each patient before and after preoperative administration of topical 0.5% moxifloxacin. Vitreous samples were collected at the beginning and end of surgery. All 4 consecutive specimens from each eye were cultured using direct culturing techniques under aerobic and anaerobic conditions. The primary outcome measure was the incidence of bacterial contamination of the vitreous cavity at the start and end of vitrectomy. The secondary measures were the incidence of bacterial contamination of the ocular surface and the disinfection rate with preoperative moxifloxacin. Of the 81 eyes (40 eyes in the 25-gauge MIVS group; 41 eyes in the 20-gauge PPV group), the incidences of positive bacterial isolation at the 4 time points of sample collection were 77.5%, 62.3%, 22.5%, and 0% in the former group and 82.9%, 63.4%, 2.4%, and 0% in the latter group. Although the rate of bacterial contamination of the ocular surface significantly (P<0.001) decreased after preoperative moxifloxacin administration in both groups, transconjunctival 25-gauge MIVS had a significantly (P = 0.007) higher incidence of vitreous contamination at the beginning of surgery compared with conventional 20-gauge PPV. The multivariate model showed that 25-gauge MIVS (odds ratio, 11.27; P = 0.027; 95% confidence interval, 1.31-96.79) was the factor prognostic of vitreous contamination at the beginning of surgery. Propionibacterium acnes was identified most often in the vitreous samples (80% of cases), which was consistent with the commensal bacteria isolated from the ocular surface. The higher incidence of bacterial contamination of the vitreous cavity at the beginning of 25-gauge MIVS suggests the increasing risk of direct inoculation of ocular surface flora into the vitreous cavity through the transconjunctival trocar-cannula system compared with conventional 20-gauge PPV. However, vitreous cavity contamination can be eliminated during vitrectomy in most cases. Proprietary or commercial disclosure may be found after the references.

A 27–Gauge Instrument System for Transconjunctival Sutureless Microincision Vitrectomy Surgery

To evaluate the efficiency, preliminary safety, and feasibility of a 27-gauge instrument system for transconjunctival microincision vitrectomy surgery (MIVS) in a variety of vitreoretinal diseases. Experimental, interventional case series. Thirty-one eyes (31 patients) underwent a variety of vitreoretinal procedures using the 27-gauge transconjunctival MIVS system to treat epiretinal membrane (n = 10), idiopathic macular holes (n = 7), diabetic vitreous hemorrhage (n = 5), vitreous opacity with suspicion of intraocular lymphoma (n = 4), focal diabetic traction retinal detachment (n = 3), macular traction syndrome (n = 1), and macular edema secondary to central retinal vein occlusion (n = 1). We developed a 27-gauge instrument system that includes an infusion line, a high-speed vitreous cutter, an illumination system, and a variety of vitreoretinal instruments, such as membrane forceps and sharp-tipped endophotocoagulation probes. The duty cycle of the 27- and 25-gauge cutters was measured for several cut rates using a high-speed imaging camera. Infusion and aspiration rates were measured using balanced saline solution (BSS) and porcine vitreous with different aspiration levels. Surgical outcomes, including anatomic success, visual outcomes, operating times, and intraoperative and postoperative complications, were evaluated. Duty cycle of cutters, infusion and aspiration rates, and surgical results of 27-gauge vitrectomy. Although the infusion and aspiration rates of the 27-gauge system measured in BSS were reduced to an average of 62% and 80%, respectively, compared with those of the 25-gauge system, the duty cycle of the 27-gauge cutter, 61% at 1000 cpm and 38% at 1500 cpm, was equal to or better than those of the 25-gauge cutter (62% and 28%, respectively). Analysis of the fluid dynamics showed that vented gas-forced infusion can be set to range from 20 to 30 mmHg to control intraocular pressure (IOP) during 27-gauge vitrectomy. Anatomic success was achieved in all study eyes (100%); 20 eyes (65%) had visual improvement of 3 lines or more. No eyes required conversion to larger gauge instrument. All sclerotomies self-sealed without hypotony (IOP < or = 7 mmHg) from 1 day postoperatively. Although the fluid dynamics and cutting efficiency of 27-gauge instruments are lower compared with 25-gauge MIVS, the 27-gauge system is feasible and may reduce concerns about wound sealing-related complications in selected cases. Proprietary or commercial disclosure may be found after the references.

Comparison of 25- and 23-gauge sutureless microincision vitrectomy surgery in the treatment of various vitreoretinal diseases

To compare the effectiveness and safety of 25- and 23-gauge sutureless microincision vitrectomy surgery (MIVS) in the management of various vitreoretinal diseases. Eighty-five consecutive patients undergoing sutureless vitrectomy during January to April 2008 were randomized to either 25- or 23-gauge MIVS. Data collected prospectively included best-corrected visual acuity (BCVA), operation time, postoperative visual recovery, postoperative anterior segment change, and complications. The most common indications for MIVS were macular hole, macular pucker, vitreous haemorrhage, and diabetic traction retinal detachment. Mean operation times of the 25-gauge (n=38) and 23-gauge groups (n=47) were 33.68 and 34.47 min, respectively (P=0.942). Mean BCVA improved significantly in both the 25- and 23-gauge groups when measured 3-month postoperatively. There was no between-group difference in either the degree or the rate of postoperative visual recovery. Seven patients in the 23-gauge group, compared with three in the 25-gauge group, required suturing of sclerotomy at the end of the surgery. No patients in either group developed postoperative wound leakage or endophthalmitis. Our prospective study suggests that, within the limited indications, both 25- and 23-gauge MIVS are equally effective, with similar safety profiles. Gauge selection thus may be made according to a surgeon's preference and the availability of appropriate instruments.