25-gauge Instruments Research Articles

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.

Localized versus 360-degree laser photocoagulation with limited pars plana vitrectomy in the management of primary rhegmatogenous retinal detachment

BackgroundTo compare the efficacy of intraoperative localized and 360-degree laser photocoagulation in 23-gauge limited pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD).MethodsThis retrospective, comparative, consecutive, interventional study included 155 eyes of 155 patients who underwent primary repair of RRD utilizing 23-gauge PPV with at least six months of follow up. Medical records were retrospectively reviewed, and the corresponding demographic data, preoperative ophthalmic features, surgical management, and postoperative course were recorded. Main outcome measures included single surgery anatomical success, pre- and post-operative visual acuity, and complications.ResultsEighty-three patients (group A) received localized laser photocoagulation in PPV, while the remaining 72 patients (group B) received underwent circumferential 360-degree laser photocoagulation in PPV. Two skilled-surgeons performed all the surgeries, and 23-gauge PPV instrumentation, a wide-angle viewing system, endolaser photocoagulation, and gas tamponade were used in each case. No significant difference was identified in baseline characteristics. The single surgery anatomical success rate was 96.4 % in group A, and 95.8 % in group B, showing no significant difference (p = 1.00). Primary anatomical failure was caused by re-detachment due to break in 2 eyes in each group (no new break 1 eye, new break 1eye in group A, 2 eyes with no new break in group B), and proliferative vitreoretinopathy in 1 eye in each group. Other complications were epiretinal membrane in 7 eyes (3 in group A, 4 in group B), and macular hole in 1 eye in group B. There were no differences in pre- and post-operative best-corrected visual acuity (BCVA) as well as BCVA improvement (p=0.144, p=0.866 and p=0.263, respectively).ConclusionLocalized laser photocoagulation showed no difference in anatomic and visual outcome in RRD patients, when compared with 360-degree laser photocoagulation in limited PPV. Routine circumferential 360-degree laser photocoagulation may not be necessary in vitrectomy surgery for primary rhegmatogenous retinal detachment without severe PVR.

CLINICAL PROFILE AND VISUAL OUTCOME AFTER ERM REMOVAL- AN EXPERIENCE FROM A TERTIARY CARE REFERRAL CENTER IN NORTH INDIA

Introduction: ERM is a cellular proliferation on the inner retinal surface and possesses contractile properties which leads to variable visual symptoms.
 Method: Thirty-four patients affected with epiretinal membrane were enrolled in this study. All patients underwent standard three port pars plana vitrectomy using standard 23-gauge instruments. Both ERM and ILM peels were performed in a circumferential pattern around the fovea. Patients were followed for 6 months. The visual outcome measures included postoperative logMAR visual acuity. The anatomical outcome was measured as decrease in foveal thickness on spectral domain optical coherence tomography (SD-OCT). Perioperative factors including duration of symptoms, preoperative visual acuity, etiology, membrane type and leakage on fundus fluorescein angiogram were correlated with the final visual outcomes.
 Results: The mean age of the patients in this study was 60.25 17.5 years with a range of 16 to 80 years. 19 patients (56%) were males. 33 patients had a unilateral ERM and 1 patient had an ERM in both eyes. Diminution of vision was the most common symptom in 34 patients, distortion of vision (metamorphopsia) was seen in 20 (58.8%) patients. The mean pre-operative log MAR best corrected visual acuity (BCVA) was 1.4±0.77 and the mean post-operative log MAR best corrected visual acuity (BCVA) was 0.9 ±0.63. Out of 34 patients in our study, 31 (91.2%) had improvement in VA, and the remaining 3 (8.82%) patients had no improvement and none of the patients had decreased vision. 16 patients had ≥2 lines of improvement in visual acuity. 15 patients had less than 2 lines of improvement.
 Conclusion: ERMs pose a significant risk to compromise the vision and affect varied age groups. ERM removal through standard three port pars plana vitrectomy offers an effective and safe procedure with better post operative visual outcomes.

Risk Assessment of Aerosol Generation During Vitreoretinal Surgery Using High Speed Imaging Amidst the COVID-19 Pandemic.

PurposeThe purpose of this study was to discuss the propensity of aerosol and droplet generation during vitreoretinal surgery using high speed imaging amidst the coronavirus disease 2019 (COVID-19) pandemic.MethodsIn an experimental set up, various steps of vitreoretinal surgery were performed on enucleated goat eyes. The main outcome measures were visualization, quantification of size, and calculation of aerosol spread.ResultsDuring intravitreal injection, insertion of cannulas, lensectomy, and vitrectomy with both 23 and 25-gauge instruments, with either valved or nonvalved cannulas, aerosols were not visualized which was confirmed on imaging. Although there was no aerosol generation during active fluid air exchange (FAE), there was bubbling and aerosol generation at the exit port of the handle during passive FAE. Under higher air pressure, with reused valved and fresh nonvalved cannulas, aerosol generation showed a trajectory 0.4 to 0.67 m with droplet size of 200 microns. Whereas removing cannulas or suturing under active air infusion (35 mm Hg and above) aerosols were noted.ConclusionsBased on the above experiments, we can formulate guidelines for safe vitrectomy during COVID-19. Some recommendations include the use of valved cannulas, avoiding passive FAE or to direct the exit port away from the surgeon and assistant, and to maintain the air pressure less than or equal to 30 mm Hg.Translational RelevanceIn the setting of the COVID-19 pandemic, the risk from virus laden aerosols, as determined using an experimental setup, appears to be low for commonly performed vitreoretinal surgical procedures.

SHORT-TERM OUTCOMES OF HYBRID 23-, 25-, AND 27-GAUGE VITRECTOMY FOR COMPLEX DIABETIC TRACTIONAL RETINAL DETACHMENT REPAIR.

To describe the short-term outcomes of complex diabetic retinal detachment repair using hybrid 23-gauge or 25-gauge vitrectomy instruments with a 27-gauge vitrectomy system. Retrospective, interventional, consecutive case series. Ten eyes of 10 patients undergoing hybrid pars plana vitrectomy for diabetic tractional retinal detachment were reviewed. Combined use of 25-gauge and 27-gauge instrumentation was used in 8 of 10 eyes and combined use of 23-gauge and 27-gauge instrumentation in 2 of 10 eyes. In all cases, a 27-gauge vitreous cutter was used for membrane dissection and delamination. All eyes had successful anatomical reattachment at a mean follow-up of 207 ± 55 days. Snellen visual acuity improved from a mean of 20/822 preoperatively to 20/566 at the final follow-up (P = 0.55). Mean intraocular pressure remained stable at 13 ± 3.4 mmHg preoperatively to 13.6 ± 5.4 mmHg at the final follow-up (P = 0.76). No intraoperative or postoperative complications were encountered. Concurrent use of the 27-gauge vitreous cutter with 23-gauge or 25-gauge instrumentation was effective during diabetic tractional retinal detachment repair. This hybrid technique was not associated with any significant intraoperative or short-term postoperative complications.

Non-Lasered Drainage Retinotomies for Repair of Primary Rhegmatogenous Retinal Detachments

Drainage retinotomies are a technique used for treating rhegmatogenous retinal detachments (RRDs). These retinotomies are commonly surrounded by barricade laser. This paper aims to evaluate operative success of non-lasered drainage retinotomies during 25-gauge pars plana vitrectomy (PPV) for repair of primary RRD. Retrospective review of a consecutive interventional case series. Study includes 45 eyes of 45 patients who underwent 25-gauge PPV with a non-lasered drainage retinotomy for primary RRD. Eyes with previous retinal detachments or less than 3 months of follow-up were excluded. All PPV with non-lasered drainage retinotomies were carried out by one surgeon (RFI); 25-gauge PPV instrumentation, a wide-angle viewing system, endolaser photocoagulation, and air or sulfur hexafluoride gas tamponade were utilized for each eye. Single surgery anatomical success was achieved in 42 out of 45 eyes (93%). Retinal detachment repair utilizing non-lasered drainage retinotomies had a high anatomic success rate comparable to that of standard retinal detachment repair.1,2 [Ophthalmic Surg Lasers Imaging Retina. 2018;49:955-960.].

VISUAL AND ANATOMICAL OUTCOMES AFTER DIABETIC TRACTION AND TRACTION-RHEGMATOGENOUS RETINAL DETACHMENT REPAIR.

To evaluate visual and anatomical outcomes of diabetic tractional retinal detachment repaired with pars plana vitrectomy. Operative records were used to retrospectively identify all patients with tractional retinal detachments secondary to proliferative diabetic retinopathy surgically repaired with pars plana vitrectomy between November 1, 2009, and January 1, 2015 at the LAC + USC (Los Angeles County + University of Southern California) Medical Center. A total of 403 eyes with diabetic tractional retinal detachment in 359 patients were included. Successful reattachment of the retina was achieved in 87.6% of eyes after one surgery and 92.6% of eyes at the final follow-up. Best-corrected visual acuity at the final follow-up improved two or more lines in 56.3% of eyes, was stable in 23.8% of eyes, and decreased two or more lines in 19.9% of eyes. Eyes repaired with 23-gauge and 25-gauge vitrectomy systems had similar success rates as eyes treated with 20-gauge instrumentation (P = 0.73). Eyes receiving silicone oil tamponade had lower single-surgery reattachment rates (77.6% vs. 87.6%; P = 0.013), lower reattachment rates at the final follow-up (85.7% vs. 92.6%; P = 0.048), and higher rates of vision loss (34.7% vs. 19.9%; P < 0.0001) but were more likely to have concurrent rhegmatogenous detachment (47.0% vs. 21.3%; P < 0.0001) and macula involving detachment (74.5% vs. 60.0%; P < 0.0001). In this large, single-center retrospective study of patients with advanced diabetic tractional retinal detachment, vitrectomy achieved excellent anatomical outcome and improved or stabilized vision in 80.1% of eyes. Smaller gauge vitrectomy systems were found to have similar outcomes to 20-gauge instrumentation.

Adjunctive Intravitreal Bevacizumab with Vitrectomy for Diabetic Vitreous Hemorrhage

Background: Postoperative vitreous hemorrhage (VH) following pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) is a common event, with a reported incidence of 29% to 75%.This complication delays visual rehabilitation, interferes with fundus examination, and may necessitate additional surgical procedures. Vascular endothelial growth factor (VEGF) is an angiogenic mitogen, and the involvement of VEGF in PDR has been suggested by studies that have demonstrated that VEGF concentrations were markedly elevated in both vitreous and aqueous fluids of patients with active PDR compared with samples from patients without diabetes, with NPDR, or with quiescent PDR. Bevacizumab (Avastin®, Genentech, Inc., South San Francisco, CA) is a full-length recombinant humanized monoclonal antibody that binds to all isoforms of VEGF. Aim of the Work: to evaluate the safety and efficacy of intravitreal bevacizumab (IVB) at the end of vitrectomy operation for prevention of postoperative rebleeding in patients with diabetic vitreous hemorrhage. Patients and Methods: The study included 20 eyes of 20 patients undergoing PPV for severe non-clearing vitreous hemorrhage for more than 1 month. Eligible eyes were randomly assigned to one of two groups: Group A (10 eyes) did not receive any intravitreal injection and Group B (10 eyes) received 1.25 mg IVB injection at the end of surgery. All patients were subjected to complete history taking and full ophthalmic examination including best-corrected visual acuity, anterior segment examination, fundus examination and B-scan ultrasonography was performed. All patients underwent three-port pars plana vitrectomy using 23-gauge instrumentation under local anesthesia. At the end of surgery, fluid-air exchange was performed and the intraocular air is left as tamponade in selected cases. The follow up period occurred over 1 week, 1 month and 3 months. The main outcome measures were occurrence of vitreous hemorrhage and BCVA. Results: At 1 month after surgery, the incidence of early postoperative VH was 30% and 20% in Group A and B, respectively (p = 0.641). Mild vitreous hemorrhage (grade 1) was the major component of early VH at 1 month (20% of 30% and 10% of 20%, in Group A and B, respectively). Analysis of changes in the mean BCVA at 1 month after surgery showed significant improvement from the preoperative BCVA in all study groups, the mean differences between pre-BCVA (Log MAR) and post BCVA (Log MAR) among the studied groups was 0.865 ± 0.351 with statistically significant difference between the two groups (p = 0.000).the mean differences between pre-BCVA (Log MAR) and post BCVA (Log MAR) among the studied groups was 0.865 ± 0.351 with statistically significant difference between the two groups (p = 0.000). At 3 months after surgery, the incidence of late postoperative VH was 20.0% and 0.00% in Group A and B, respectively, with no significant difference between the two groups(P=0. 237). Again, analysis of changes in the mean BCVA at 3 months after surgery showed significant improvement to 1.080 ± 0.2098 and 0.870 ± 0.17767 in Group A and B, respectively, with statistically significant difference between the two groups (p >0.027). Conclusion: The incidence of late postoperative vitreous hemorrhage is lower than that of early postoperative vitreous hemorrhage and is not affected by intraoperative intravitreal bevacizumab injection and Adjunctive use of intravitreal bevacizumab with pars plana vitrectomy for complications of PDR is safe and well-tolerated with no serious ocular or systemic adverse events.

Adjunctive Intravitreal Bevacizumab with Vitrectomy for Diabetic Vitreous Hemorrhage

Background: Postoperative vitreous hemorrhage (VH) following pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) is a common event, with a reported incidence of 29% to 75%.This complication delays visual rehabilitation, interferes with fundus examination, and may necessitate additional surgical procedures. Vascular endothelial growth factor (VEGF) is an angiogenic mitogen, and the involvement of VEGF in PDR has been suggested by studies that have demonstrated that VEGF concentrations were markedly elevated in both vitreous and aqueous fluids of patients with active PDR compared with samples from patients without diabetes, with NPDR, or with quiescent PDR. Bevacizumab (Avastin®, Genentech, Inc., South San Francisco, CA) is a full-length recombinant humanized monoclonal antibody that binds to all isoforms of VEGF. Aim of the Work: to evaluate the safety and efficacy of intravitreal bevacizumab (IVB) at the end of vitrectomy operation for prevention of postoperative rebleeding in patients with diabetic vitreous hemorrhage. Patients and Methods: The study included 20 eyes of 20 patients undergoing PPV for severe non-clearing vitreous hemorrhage for more than 1 month. Eligible eyes were randomly assigned to one of two groups: Group A (10 eyes) did not receive any intravitreal injection and Group B (10 eyes) received 1.25 mg IVB injection at the end of surgery. All patients were subjected to complete history taking and full ophthalmic examination including best-corrected visual acuity, anterior segment examination, fundus examination and B-scan ultrasonography was performed. All patients underwent three-port pars plana vitrectomy using 23-gauge instrumentation under local anesthesia. At the end of surgery, fluid-air exchange was performed and the intraocular air is left as tamponade in selected cases. The follow up period occurred over 1 week, 1 month and 3 months. The main outcome measures were occurrence of vitreous hemorrhage and BCVA. Results: At 1 month after surgery, the incidence of early postoperative VH was 30% and 20% in Group A and B, respectively (p = 0.641). Mild vitreous hemorrhage (grade 1) was the major component of early VH at 1 month (20% of 30% and 10% of 20%, in Group A and B, respectively). Analysis of changes in the mean BCVA at 1 month after surgery showed significant improvement from the preoperative BCVA in all study groups, the mean differences between pre-BCVA (Log MAR) and post BCVA (Log MAR) among the studied groups was 0.865 ± 0.351 with statistically significant difference between the two groups (p = 0.000).the mean differences between pre-BCVA (Log MAR) and post BCVA (Log MAR) among the studied groups was 0.865 ± 0.351 with statistically significant difference between the two groups (p = 0.000). At 3 months after surgery, the incidence of late postoperative VH was 20.0% and 0.00% in Group A and B, respectively, with no significant difference between the two groups(P=0. 237). Again, analysis of changes in the mean BCVA at 3 months after surgery showed significant improvement to 1.080 ± 0.2098 and 0.870 ± 0.17767 in Group A and B, respectively, with statistically significant difference between the two groups (p >0.027). Conclusion: The incidence of late postoperative vitreous hemorrhage is lower than that of early postoperative vitreous hemorrhage and is not affected by intraoperative intravitreal bevacizumab injection and Adjunctive use of intravitreal bevacizumab with pars plana vitrectomy for complications of PDR is safe and well-tolerated with no serious ocular or systemic adverse events.

Long-Term Safety and Efficacy of Limited Vitrectomy for Vision Degrading Vitreopathy Resulting from Vitreous Floaters

Vitreous floaters can lower visual acuity (VA) and degrade contrast sensitivity function (CSF). Limited vitrectomy improves VA and normalizes CSF, but long-term results in a large series with objective quantitative outcome measures are lacking. Case series. One hundred ninety-five eyes of 145 patients (87 men, age = 57.6 ± 4.3 years; 58 women, age= 61.5 ± 12.0 years) reporting bothersome vitreous floaters were compared to 70 age-matched controls. Posterior vitreous detachment (PVD) alone was the cause in 96/195 (49.2%), myopic vitreopathy alone was the cause in 30/195 (15.4%), PVD with myopic vitreopathy was the cause in 56/195 (28.7%), and asteroid hyalosis was the cause in 13/195 eyes (6.7%). Limited vitrectomy with 25-gauge instruments was performed without surgical PVD induction, preserving 3 to 4 mm of retrolental vitreous in phakic eyes. Follow-up averaged 32.6 ± 23.5 months (range, 3-115 months), with 2 years or more in 144 eyes, 3 years or more in 69 eyes, 4 years or more in 51 eyes, and 5 years or more in 24 eyes. Visual acuity, 39-item National Eye Institute Visual Function Questionnaire (VFQ) results, CSF (Weber index), and quantitative ultrasonography results. After surgery, vitreous echodensity decreased by 94.1% (P < 0.0001) and VFQ results improved by 19.3% (P < 0.0001). Preoperative VA was 0.68 ± 0.21, improving to 0.77 ± 0.19 after surgery (P < 0.0001). Preoperative CSF was degraded by 91.3% compared with controls (P < 0.0001), normalizing at 1, 3, 6, 12, 24, 36, and 48 months after surgery (P < 0.00005 for each). There were no cases of endophthalmitis. There were 3 retinal tears and 3 retinal detachments that underwent successful repair. Clinically significant vitreous hemorrhage developed in 2 patients, clearing spontaneously. Two macular puckers and 4 recurrent floaters from new PVD were cured by re-operation. Cataract surgery occurred in 21 of 124 patients (16.9%; mean age, 64 ± 7 years; none younger than 53 years), an average of 13.1 ± 6.8 months after vitrectomy. Limited vitrectomy for Vision Degrading Vitreopathy decreases vitreous echodensity, improves patient well-being, improves VA, and normalizes CSF. The long-term efficacy and safety profiles suggest this may be a safe and effective treatment for clinically significant vitreous floaters, warranting a prospective randomized trial.

Long-Term Visual Outcomes and Safety Profile of 27-Gauge Pars Plana Vitrectomy for Posterior Segment Disease

To report longer-term outcomes of 27-gauge pars plana vitrectomy (PPV) in eyes with posterior segment disease. Multicenter, retrospective, interventional case series. A total of 390 eyes of 360 patients undergoing 27-gauge PPV for a vitreoretinal surgery indication. Three-port, transconjunctival, 27-gauge PPV. Change in visual acuity (VA) and occurrence of intraoperative and postoperative complications with a minimum follow-up of 365 days. Mean follow-up was 715±332 days (median, 514; range, 365-1440 days). Surgical indications included epiretinal membrane (ERM) (n= 121), vitreous floaters (n= 69), diabetic tractional retinal detachment (n= 49), vitreous hemorrhage (n= 40), full-thickness macular hole (n= 33), recurrent proliferative vitreoretinopathy (PVR)-related retinal detachment (n= 18), primary rhegmatogenous retinal detachment (RRD) (n= 17), silicone oil removal (n= 16), dislocated intraocular lens (n= 10), submacular hemorrhage (n= 7), endophthalmitis (n= 6), and retained lens material (n= 4). Mean logarithm of the minimum angle of resolution (logMAR) VA improved from 0.72±0.62 (20/105 Snellen equivalent) preoperatively to 0.40±0.55 (20/50 Snellen equivalent) postoperatively (P < 0.001). No case required conversion to 23- or 25-gauge instrumentation. Postoperative complications included transient ocular hypertension in 44 eyes (11.3%), vitreous hemorrhage in 31 eyes (7.9%), and transient hypotony in 22 eyes (5.6%). Acute postoperative endophthalmitis occurred in 1 case (0.26%). Overall, 82 of 390 eyes (21.0%) underwent at least 1 additional intraocular surgery in the follow-up period, most commonly for cataract extraction (n= 40/82 eyes, 48.8%). Of the 18 eyes undergoing surgery for primary RRD, recurrent detachment due to PVR occurred in 2 eyes (11.1%). At a minimum follow-up of 1 year, 27-gauge PPV was well tolerated with low rates ofpostoperative complications across varied surgical indications, including primary and complex retinal detachment.

Implantation of Modular Photovoltaic Subretinal Prosthesis.

Establish the surgical procedure for subretinal implantation of multiple photovoltaic arrays for the restoration of sight. Multiple silicon photovoltaic arrays of 1 mm in diameter and 30 µm in thickness were implanted subretinally via single retinotomy in rabbits. Ophthalmoscopic imaging and optical coherence tomography (OCT) were used to validate the implants' placement. Vitrectomy, followed by subretinal fluid injection for retinal detachment and retinotomy, allowed accurate placement of seven modules in the bleb, covering approximately a 3.5-mm diameter area on the retina via a single 1.5-mm retinotomy. OCT confirmed complete reattachment of the retina over the implants. Subretinal implantation of multiple photovoltaic arrays via a single retinotomy, followed by their tiling, minimizes the scleral and retinal incisions and provides better fit to the spherical shape of the eye ball, compared to a single, larger module. Such minimally traumatic procedure can be performed with 20-gauge intraocular instruments.

Comparison of microbiology and visual outcomes of patients undergoing small-gauge and 20-gauge vitrectomy for endophthalmitis.

BackgroundThe role of pars plana vitrectomy (PPV) for endophthalmitis has evolved over recent decades but the literature is lacking on comparisons between small-gauge and 20-gauge vitrectomy.ObjectiveTo evaluate evolving etiological and microbiological trends in patients undergoing vitrectomy for endophthalmitis and to compare culture-positive rates and visual outcomes between small-gauge (23- and 25-gauge) and 20-gauge instrumentation during vitrectomy for endophthalmitis.MethodsTen-year retrospective comparative case series and prospective laboratory in vitro testing. Tertiary care academic referral center. Patients who underwent PPV for endophthalmitis between 2003 and 2013. Vitreous biopsies were obtained in all cases. The effect of vitrectomy gauge (20-, 23-, and 25-gauge) and vitreous cutting rate (1,500 and 5,000 cuts per minute) on the viability of bacterial culture was evaluated in an in vitro prospective laboratory investigation.Main outcome measuresComparison of etiology, microbiology culture-positive rates, and visual outcomes between small-gauge and 20-gauge instrumentation in patients undergoing PPV for infectious endophthalmitis.ResultsA total of 61 cases of vitrectomy for endophthalmitis were identified over a 10-year period; of these, 34 were treated with small-gauge (23- and 25-gauge) vitrectomy and 27 were treated with 20-gauge vitrectomy. In the small-gauge group, 12 cases (35.3%) yielded culture-positive results versus 20 cases (74.1%) with culture positivity in the 20-gauge cohort (P=0.002). The most common cause of endophthalmitis was cataract surgery and the most frequently identified organism was coagulase-negative Staphylococci in both groups. There was no significant difference in mean postoperative visual acuities between groups (P=0.33). Etiological trends indicate an increase in endophthalmitis due to intravitreal injection in the small-gauge group (n=9) compared to the 20-gauge group (n=3) (P=0.001). In vitro laboratory testing revealed no significant difference in rates of culture growth for different vitrectomy gauge sizes or vitreous cutting speeds.Conclusion and relevanceSmall-gauge vitrectomy for endophthalmitis yields final visual outcomes comparable to 20-gauge instrumentation. A significant difference in culture-positive rates was observed between small-gauge and 20-gauge instrumentation for vitrectomy in endophthalmitis; however, laboratory testing indicates this is not related to either vitreous gauge size or cutter speed. Intravitreal injections are emerging as a common etiology of vitrectomy for endophthalmitis.

Combined 23-Gauge Vitrectomy and Femtosecond Laser-Assisted Cataract Surgery

Background: The aim of this study was to assess the safety and surgical results of femtosecond laser-assisted phacovitrectomy. Methods: A retrospective analysis of the medical records of patients over 50 years of age with vitreoretinal pathology, who had undergone pars plana vitrectomy using 23-gauge instruments and femtosecond laser-assisted cataract surgery and implantation of an intraocular lens, was performed at the Instituto de Microcirugía Ocular between June 2012 and September 2013. The diameter of the anterior capsulorhexis was set at 4.8 mm in cases where a gas tamponade was used and at 5 mm in all other cases. During the pars plana vitrectomy, posterior capsulotomy was performed on all eyes. An assessment was carried out of preoperative characteristics, surgical indications, postoperative results and complications. Only patients with a minimum of 3 months of follow-up were included. Results: A total of 21 eyes in 21 patients (71.4% women) were treated. Mean age (±SD) was 65.8 ± 6.4 years (range 53-76). The most common indication for surgery was epiretinal membrane (61.9%), followed by vitreous haemorrhage (23.8%) and macular hole (14.3%). The mean preoperative best corrected visual acuity (BCVA) was 0.81 ± 1.01 logMAR and the mean postoperative BCVA was 0.12 ± 0.19 logMAR (p = 0.003). 85.7% of patients improved their visual acuity. The remaining patients maintained their visual acuity. The only intraoperative complication related to femtosecond laser was 1 case of suction loss (4.8%). A patient with rhegmatogenous retinal detachment discovered during surgery required an additional circular scleral procedure and developed synechiaes in the early postoperative period (<1 month). There were no cases of subluxation of the intraocular lens. Mean follow-up was 6 months (range 3-14). Conclusions: The application of femtosecond laser in phacovitrectomy is a safe and effective technique that presents advantages compared to conventional techniques in cases of macular pathology and/or vitreous haemorrhage.

27-Gauge vitrectomy.

Ten years or more have passed since the current concept of 25-gauge transconjunctival sutureless vitrectomy with a trocar-cannula system emerged. There is no doubt that current microincision vitrectomy surgery with 25- or 23-gauge instrumentation has simplified the vitrectomy procedure and has provided numerous potential advantages over traditional 20-gauge surgery. The established theory regarding surgical wounds is that 'much smaller is better'. Along with the development of new-generation vitrectomy machines with ergonomic instruments, surgeons have been shifting dramatically from 20-gauge systems to 23- and 25-gauge systems over the last years. Thanks to recent innovations and improvements in high-end multifunctional vitrectomy machines and ultrahigh-speed cutters, the development of powerful light sources, and wide-angle viewing systems, several new techniques have also encouraged us to launch the development of a 27-gauge vitrectomy system over the past several years. Similar to the recent evolution in 23- and 25-gauge systems, further development and refinement of the functionality of instruments with a gauge of 27 or more are under way and will continue over the coming years, which in the future will allow us to establish this system for ultra-minimally invasive surgery for the full spectrum of vitreoretinal pathologies.

No excuse for not looking

Any iatrogenic complication would be upsetting to a surgeon, knowing that a patient acquired an undesirable effect as a result of something that he or she did during surgery. Causing retinal breaks or retinal detachments (RD) is a prime example of one such iatrogenic complication. The fact that we, as surgeons, are responsible is all the more obvious when patients did not have retinal breaks or RD before surgery. In this issue, Jalil et al. conducted a large retrospective study of patients undergoing pars plana vitrectomy (PPV) for indications other than rhegmatogenous RD, comparing the incidence of iatrogenic retinal breaks and RD between 20-gauge standard PPV and 23-gauge transconjunctival “sutureless” vitrectomy (TSV) [1]. They examined over 900 patients that underwent PPV over a 2-year period for epiretinal membrane, macular hole, vitreo-macular traction, advanced proliferative diabetic retinopathy including vitreous haemorrhage and tractional RD, and retained lens fragments. Patients with rhegmatogenous RD, previous PPVand perforating injuries were deliberately excluded. They found that the incidence of entry site break was 7.9 % with 20gauge standard PPV and 1.7 % with 23-gauge TSV. In the same issue is a study by Cha et al. involving over 1,300 vitrectomies and they found iatrogenic peripheral retinal breaks to be 6.2 % with 20-gauge standard PPV and 1.6 % with 23-gauge TSV [2]. The results were not surprising. Most of us have the impression that the use of cannula was associated with lower incidence of “entry-site” tear. It does not appear to depend on the gauge of the instruments used either. In 1985, Machemer and Hickingbotham introduced a 3-port microcannular system for closed vitrectomy [3]. This system did not gain widespread popularity, partly because of the additional cost involved and partly because the sclerotomies were nearer 19-gauge in order to accommodate the 20-gauge instruments. Nevertheless, those who had used the system, including myself, attest to the fact that entry site tears were rare. Similarly, Covert et al. reported intraoperative retinal breaks in a series of TSV (with cannula) and found that the incidence to be similar between 20-, 23and 25-gauge (being 1 in 59 eyes, 3 in 76 and 3 in 76 cases respectively) [4]. Why should the use of a cannula system be associated with a lower incidence of entry site tears? It is speculated that the cannula protects the vitreous base from the trauma of repeated insertion of instruments, especially those with awkward shapes (such as scissors and forceps). However, with or without cannula, vitreous incarceration into the sclerotomies is inevitable. Indeed, with a sutureless system, the maintenance of post-operative intraocular pressure is dependent on vitreous plugging the openings. With a cannula system, it is the basal vitreous gel around the sclerotomy that becomes incarcerated, whereas without the protection of a cannula, the posterior hyaloid face can become incarcerated and therefore traction on the posterior border of the vitreous base remote from the sclerotomy may ensue. There are probably many additional confounding factors for iatrogenic retinal breaks formation: the complexity of the surgical manipulation; the extent of vitreous base shaving; the efficiency of different cutters and the experience of the surgeon might all influence the rate of unintentional retinal tears. Therefore, it is unlikely that a randomized trial would ever be conducted controlling for all these confounding factors. The D. Wong (*) Department of ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Head of the Department of Ophthalmology Room 301, Block B, Cyberport 4, Hong Kong, Hong Kong Special Administrative Region, People’s Republic of China e-mail: shdwong@hku.hk

Surgical results of combined pars plana vitrectomy and phacoemulsification for vitreous hemorrhage in PDR

BackgroundThe purpose of this study was to evaluate the effectiveness, safety, and incidence of complications after combined clear corneal phacoemulsification with intraocular lens implantation and pars plana vitrectomy in eyes with proliferative diabetic retinopathy coexistent with significant cataract.MethodsEighty-five eyes of 85 patients with proliferative diabetic retinopathy underwent primary standard three-port vitrectomy with 20-gauge instruments and phacoemulsification with intraocular lens implantation for vitreous hemorrhage from 2008 to 2011. The main outcome measures were visual outcomes and surgical complications.ResultsForty patients were male and 45 were female. Their age ranged from 40 to 77 years with a mean of 59.6 years. The mean follow-up was 13 months, with a range of 6–48 months. The preoperative logMAR visual acuity changed from 2.62 ± 0.6 to 0.8 ± 0.7 postoperatively. Postoperatively, visual acuity improved in 79 eyes (92.9%), and did not change in six eyes (7.1%). Intraoperative complications were transient corneal edema (five eyes) and posterior capsular rupture (one eye). Postoperative complications consisted of transient intraocular pressure elevation (25 eyes), corneal epithelial defects (six eyes), anterior chamber reaction (four eyes), hyphema (two eyes), posterior synechiae (four eyes), vitreous hemorrhage (23 eyes), retinal tears (five eyes), retinal detachment (one eye), and neovascular glaucoma (one eye).ConclusionOur study suggests that the combined operation of pars plana vitrectomy, phacoemulsification, and intraocular lens implantation is safe and effective for patients with proliferative diabetic retinopathy. We believe that the visual outcome and complications depended primarily on underlying posterior segment pathology and were not related to the combined procedure technique.

Anatomic and functional outcomes of 25-gauge vitrectomy for repair of eyes with rhegmatogenous retinal detachment complicated by proliferative vitreoretinopathy

BackgroundThe purpose of this study was to evaluate the outcome of 25-gauge vitrectomy for repair of rhegmatogenous retinal detachment (RRD) complicated by proliferative vitreoretinopathy (PVR).MethodsTwenty-seven eyes of 27 patients who had undergone 25-gauge vitrectomy for grade C PVR were investigated retrospectively. The surgical procedures, anatomic success, and best-corrected visual acuity were assessed.ResultsThe mean number of operations was 1.4 (range 1–4). During the 25-gauge vitrectomy, 20-gauge instruments were needed in eleven eyes (40.7%) to remove resilient fibrous preretinal membranes, to extract subretinal proliferations, or to remove or infuse silicone oil. The retina was reattached in 21 eyes (77.8%) after the initial vitrectomy and in 25 eyes (92.6%) at the final examination. The mean best-corrected visual acuity in logarithm of the minimal angle of resolution units was 1.36 ± 0.81 before vitrectomy and 0.79 ± 0.71 at one month, 0.73 ± 0.72 at 3 months, 0.73 ± 0.75 at 6 months, and 0.75 ± 0.78 at 12 months after vitrectomy. The best-corrected visual acuities were significantly improved compared with the preoperative ones at all postoperative assessments (P<0.001).ConclusionTwenty-five gauge vitrectomy is a relatively safe and efficacious method of treating RRD with PVR, although combined use of 20-gauge instruments may be needed for certain surgical procedures.

Comparison of the 20-Gauge Conventional Vitrectomy Technique with the 23-Gauge Releasable Suture Vitrectomy Technique

PurposeTo compare the efficacy of the transconjunctival releasable suture technique for pars plana vitrectomy using 23-gauge (23G) instruments versus the conventional 20-gauge (20G) technique.MethodsA retrospective and interventional case series was consecutively performed for 199 eyes of the 192 patients that were a part of this study. Clinical data were reviewed retrospectively regarding the operation time, preoperative and postoperative intraocular pressure, visual acuity and astigmatism for 54 consecutive patients who received a 23G releasable suture vitrectomy and for 98 consecutive patients who received a 20G conventional vitrectomy during the period between April 2007 and September 2010.ResultsMean operation time based on the operation record was 88.5 ± 20.1 minutes in the 23G releasable suture vitrectomy group and 102.1 ± 23.1 minutes in the 20G conventional vitrectomy group, respectively (p = 0.01). The last best-corrected visual acuity (BCVA) was significantly better than the preoperative BCVA in both patient groups (p = 0.01, p = 0.01). The 23G releasable suture group showed less surgically induced astigmatism than the 20G conventional vitrectomy group. Vitreous bleeding was observed to be in 6 eyes (5.9%) in the 23G group, and in 8 eyes (8.2%) in the 20G group. In addition, ocular hypertension was noted to be in 3 eyes (3.0%) in the 23G group, and 6 eyes (6.1%) in the 20G group. No serious complications such as postoperative hypotony or endophthalmitis were observed in either group.ConclusionsThe 23G releasable suture technique is as effective as the 20G conventional technique and offers several advantages.

TEMPORAL APPROACH FOR SMALL-GAUGE PARS PLANA VITRECTOMY COMBINED WITH ANTERIOR SEGMENT SURGERY

To describe our preliminary experience with temporal small-gauge pars plana vitrectomy (PPV) techniques used to treat anterior and posterior segment pathology. A retrospective consecutive case review of patients who underwent temporal PPV was performed. Patients underwent combined temporal small-gauge PPV and anterior segment intervention. Pre- and postoperative visual acuity, intraocular pressure, surgical indications, intraoperative techniques, postoperative course, and a survey to determine how the change in position affected surgery were examined. Temporal PPV was performed on 23 eyes with various posterior segment indications and anterior segment pathologies including cataract, pupillary membrane, endophthalmitis, superior filtering blebs, and anterior vitreous membranes. In 20 eyes, 23-gauge instruments were used, and in 3 eyes, 25-gauge instruments were used. Mean postoperative follow-up duration was 7.6 ± 5.0 months (range, 3-22 months). Surgical objectives were achieved in all cases, and no complications occurred in any study eye. Preoperative logarithm of the minimum angle of resolution mean visual acuity was 1.89 ± 0.76 and improved significantly on postoperative Week 1 (1.45 ± 0.81, P = 0.0003), Month 1 (1.13 ± 0.86, P = 0.0001), and at final follow-up (0.88 ± 0.79, P = 0.0001). There was no significant difference in preoperative and postoperative intraocular pressures. Surgeon surveys indicated significant advantages with a temporal approach for each anterior segment indication, no significant differences in performing the basic surgical steps of PPV, and relative ease of adopting this technique. Performing PPV from the temporal position seems to be advantageous in cases combining posterior and anterior segment surgery such as cataract extraction, pupillary membrane dissection, preservation of superior conjunctival blebs, and trimanual vitrectomy.