Iatrogenic Breaks Research Articles

Soloist performance of vitrectomy probe in proliferative diabetic retinopathy.

To evaluate the feasibility and outcomes of the sole use of 23g pars plana vitrectomy in cases with diabetic vitreous hemorrhage with vitreoretinal traction. Prospective interventional case series involving patients between January 2013 and January 2018. All eyes underwent 23g pars plana vitrectomy with internal tamponade. Intraoperative parameters including ancillary instruments, the methods used for hemostasis and complications were all recorded. Postoperative parameters including anatomic success rate, functional success, and postoperative complications were recorded and analyzed. Patients were followed up for at least 12 months. A total of 68 eyes of 66 patients were included. Intraoperative ancillary instruments were required in 5 (7.4%) eyes. None of the cases required the use of chandelier illumination, endodiathermy, or scissors. Mean best-corrected visual acuity improved significantly from LogMAR 1.67 ± 0.63 preoperative to 1.22 ± 0.38 at 1-year follow-up (P = 0.005). Functional success was achieved in 37 (54.4%) eyes at 1-year follow-up. Iatrogenic breaks occurred in 3 (4.4%) eyes, vitreous hemorrhage in 4 (5.9%) eyes, and epiretinal membranes in 3 (4.4%) eyes. Repeated vitrectomy was done in 3 (4.4%) eyes. The 23g vitrectomy probe proved to be a safe, effective, and beneficial single tool that could accomplish the diabetic vitrectomy mission exclusively with minimal aid from other instruments in cases with vitreous hemorrhage associated with vitreoretinal traction.

Twenty-seven-gauge vitrectomy for combined tractional and rhegmatogenous retinal detachment involving the macula associated with proliferative diabetic retinopathy

BackgroundTo report our experience using 27-gauge pars plana vitrectomy (PPV) system for treating patients with combined tractional and rhegmatogenous retinal detachments (CTRRD) involving the macula associated with proliferative diabetic retinopathy (PDR).MethodsRetrospective noncomparative interventional cases series of 12 patients with CTRRD associated with PDR who underwent 3-port, transconjunctival 27-gauge PPV by a single surgeon. Main outcome measures were change in Snellen best corrected visual acuity (BCVA) and occurrence of intra- and post-operative complications.ResultsTwelve eyes from 12 patients (9 men and 3 women) underwent 27-gauge PPV. Mean follow-up was 17 months (range 8–26 months). Preoperatively, BCVA of 20/400 or better was recorded in only 2 of 12 (16.7%) eyes. Postoperatively, BCVA improved to 20/400 or better in 11 of 12 (91.7%) eyes at 6 months (P = 0.001). At last follow-up, BCVA of 20/400 or better was recorded in 10 of 12 (83.3%), in comparison to 2 (16.7%) eyes at baseline (P = 0.004). The only intraoperative complication was an iatrogenic break in 1 eye (8.3%). Postoperative complications included vitreous hemorrhage in 4 eyes (33.3%) and transient ocular hypertension in 3 eyes (25.0%). At final follow-up anatomic success was confirmed in all eyes.ConclusionThe current study findings suggest that 27-gauge PPV is a safe and promising surgical technology for treating patients with CTRRD involving the macula associated with PDR. Smaller gauge instruments and higher cutting rates may facilitate the dissection and shaving of fibrovascular membranes, while minimizing intra- and post-operative complications.

Variation in the vitreoretinal configuration of Stage 4 retinopathy of prematurity in photocoagulated and treatment naive eyes undergoing vitrectomy.

Purpose:We sought to document the difference in the vitreoretinal configuration of Stage 4 retinopathy of prematurity (ROP) in photocoagulated and treatment naive eyes undergoing vitrectomy and to correlate it with surgical complexity.Methods:Consecutive eyes posted for vitrectomy with Stage 4 ROP were documented preoperatively using a RetCam for the presence of peripheral traction (PT), presence of central traction just outside the arcades, and presence of traction extending to the lens. A note was made of the following intraoperative events: lensectomy, intraoperative bleeding, and iatrogenic breaks. Wilcoxon rank-sum test was used for analysis.Results:From a total of 46 eyes, 16 and 30 eyes were from the treated and treatment naive group, respectively. More eyes in the treated group had central (P < 0.0001) and lenticular traction (P = 0.022). More eyes in the untreated group had PT (P < 0.0001). A significant number of eyes without photocoagulation needed lensectomy (P = 0.042), and no difference in intraoperative bleeding (P = 0.94) was demonstrable. Iatrogenic retinotomy occurred in three eyes, all naive. Notably, age at surgery was more in the untreated group (P = 0.00008).Conclusion:Vasoproliferative activity in all retinopathies occurs at the junction of the ischemic and nonischemic retina. In the natural course of ROP, this takes place peripherally, at the ridge. In photocoagulated eyes, this junction is displaced posteriorly due to peripheral ablation. Treated eyes manifested with posterior proliferative changes and were more amenable to lens-sparing vitrectomy. Naive eyes were older when they underwent surgery to relieve PT with greater chances of lensectomy and iatrogenic breaks.

Optic Disc Pit Maculopathy (ODP-M) Surgical Intervention and Outcome

We report the case of a 26 year old lady, presenting with complaints of gradual diminution of vision in her right eye (RE). Best corrected visual acuity (BCVA) was 20/60 and N12 in the RE and 20/20 and N6 in the left eye (LE). Fundus examination and optical coherence tomography (OCT) led to a diagnosis of optic disc pit maculopathy (ODP-M) in the RE. Pars plana vitrectomy, with an attempt to make an inner retinal fenestration adjacent to the temporal margin of the pit was done. An iatrogenic break was formed, which was used for subretinal fluid drainage and sealed by diode laser endophotocoagulation. Sulphur hexafluoride (SF6) was used for internal tamponade. At 6 months follow-up, BCVA in the RE had improved to 20/30 and N8. OCT revealed no subretinal fluid and decreased fluid in the schisis cavity. This case report therefore, demonstrates the efficacy of surgical intervention for ODP-M.

Predictors and Outcomes of Vitrectomy and Silicone Oil Injection in Advanced Diabetic Retinopathy.

PurposeTo evaluate visual and anatomical results and identify factors that influence vitrectomy and silicone oil (SO) injection outcomes in proliferative diabetic retinopathy (PDR).MethodsThis retrospective study included 236 eyes with PDR that were undergoing vitrectomy and SO injection with >3-month follow-up. The primary outcomes were final best-corrected visual acuity (BCVA) and retinal attachment rate.ResultsAt the final visit (mean, 88 ± 58 weeks), complete, partial, and no retinal attachment were observed in 86.9%, 10.6%, and 2.5% of patients, respectively. A total of 155 eyes had experienced SO removal, while 81 had SO in place. The mean initial BCVA was 1.9 ± 0.7 logarithm of the minimum angle of resolution (logMAR) and significantly improved to 1.7 ± 0.8 logMAR (p = 0.001). Initial macular detachment (adjusted odds ratio [AOR], 0.25), development of iatrogenic break (AOR, 0.25), and use of heavy SO (AOR, 0.13) were independently associated with a lower risk of final retinal attachment, and SO removal was associated with a higher incidence (AOR, 7.55). Better baseline BCVA was associated with a higher risk of final BCVA ≥20 / 200.ConclusionsDespite an encouraging outcome based on anatomical data in advanced PDR treated with vitrectomy and SO, the functional prognosis was not satisfying for patients. Eyes with better vision at baseline had a more favorable prognosis, whereas eyes with initial macular detachment, intraoperative iatrogenic break, or heavy SO showed more unfavorable outcomes. In selected cases, extending the time of SO use did not worsen the prognosis.

INTRAVITREAL CONBERCEPT (KH902) FOR SURGICAL TREATMENT OF SEVERE PROLIFERATIVE DIABETIC RETINOPATHY.

To evaluate the role, safety, and effectiveness of intravitreal conbercept (KH902) injections as an adjunct to vitrectomy in the management of severe proliferative diabetic retinopathy. A randomized controlled trial was performed on 36 eyes of 36 patients affected by vitreous hemorrhage and tractional retinal detachment, which occurred as a consequence of active proliferative diabetic retinopathy. The patients were randomly assigned to two groups. The patients in one of the groups received an intravitreal injection of conbercept in the inferior temporal sector 4 mm from the sclerocorneal limbus with a sterile technique 1 week before vitrectomy. In the group without conbercept, intraoperative bleeding occurred in 14 patients (77.8%), and in five of these cases, bleeding was significant. The use of endodiathermy was necessary in 8 patients (44.4%). In 3 patients (16.6%), iatrogenic retinal breaks occurred, and in 1 patient (5.5%), a relaxing retinotomy was performed. Endotamponade with silicone oil was performed in 12 patients (66.6%). In the group treated with conbercept, intraoperative bleeding occurred in 2 cases (11.1%). The use of endodiathermy was necessary in 1 patient (5.5%). No patients experienced iatrogenic breaks or relaxing retinotomy during the surgery. Endotamponade with silicone oil was performed in 2 patients (11.1%). Preoperative intravitreal injection of conbercept could reduce the chances of intraoperative bleeding, which are beneficial in the management of proliferative diabetic retinopathy.

Iatrogenic retinal breaks in ultrahigh-speed 25-gauge vitrectomy: a prospective study of elective cases

Background/AimsTo evaluate the incidence of intraoperative retinal breaks in the ultrahigh-speed (UHS) 25-gauge vitrectomy system in elective vitreous-retina surgery cases.MethodsA prospective series of 1676 eyes of 1306 consecutive patients. All...

Outcomes of vitrectomy for advanced diabetic retinopathy at Groote Schuur Hospital, Cape Town, South Africa.

Present limitations in primary and secondary prevention of diabetic retinopathy mean that many patients with diabetes present with advanced retinal complications, often requiring surgery (vitrectomy). To determine the outcomes of vitrectomy for advanced diabetic retinopathy and to examine context-specific risk factors that may influence outcomes and decisions affecting resource allocation. This was a retrospective cohort study of 124 vitrectomies with up to 6 months' follow-up. Visual acuity was 6/60 or worse in the better eye in 23.4% of patients at presentation. The mean visual acuity of the listed eye was 2/60. The fellow eye was considered inoperable in 20.2% of cases. Visual function declined significantly in 26.2% of patients while awaiting surgery. The average waiting time until surgery was 2.9 months (range 1 day - 9 months). Epiretinal membranes were present in 93.6% of cases, and posterior iatrogenic breaks occurred in 49.2%. Silicone oil was used in 24.2%. Visual acuity improved in 54.9%, was unchanged in 30.1%, and worsened in 14.0% of cases at 6 months. Patients with poorer vision at surgery were more likely to improve (odds ratio 2.15; p=0.048). Factors associated with a worse visual outcome were increased age at surgery (p=0.042) and posterior iatrogenic retinal breaks (p=0.007). Renal dysfunction was not associated with worse visual outcomes. Vitrectomy improved or stabilised vision in 85.0% of cases, although outcomes were unpredictable. A long waiting time to surgery contributed to patient morbidity. The presence of renal dysfunction did not predict poorer visual outcomes.

The effect of microincision vitrectomy and intravitreal injection of ranibizumab in the treatment of proliferative diabetic retinopathy

Objective To observe the effect of microincision vitrectomy assisted with intravitreaI injection of ranibizumab (IVR) in proliferative diabetic retinopathy (PDR) treatment. Methods This is a prospective, randomized, and comparative case series study. A total of 92 patients (92 eyes) with PDR were recruited to have microincision vitrectomy with (combined group) or without (PPV group) IVR. There are 48 eyes in the combined group and 44 eyes in the PPV group. The average operation time, iatrogenic breaks, the use of tamponade and electric coagulation, postoperative bleeding and best corrected visual acuity were comparatively analyzed among the two groups.The mean follow-up was (14.3±5.2) months. Results The average operation time was (59.4±18.5) min in the combined group and (74.6±16.2) min in the PPV group. The rate of silicone oil tamponade (χ2=4.619), inert gas tamponade (χ2=4.290), electric coagulation (χ2=8.039) and iatrogenic breaks (χ2=4.330) in the combined group were significantly decreased compared with PPV group(P<0.05). The mean logMAR BCVA was 0.83±0.44 in the combined group and 1.37±0.53 in the PPV group, which significantly improved from preoperatively (t=3.257, 3.012; P<0.05). The rate of BCVA improvement in the combined group was significantly higher than that in the PPV group (t=2.972, P<0.05). The incidence of the recurrent vitreous hemorrhage was 2.1% in the combined group and 9.1% in the PPV group (χ2=6.741, P<0.05). There was no severe complication associated with surgery, such as choroidal detachment, retinal detachment and endophthalmitis. Conclusion IVR before the microincision vitrectomy can shorten the operation time, reduce the use of electric coagulation and intraocular tamponade, and improve visual acuity for PDR patients. Key words: Diabetic retinopathy/surgery; Diabetic retinopathy/drug therapy; Antibodies, monoclonal/therapeutic use; Angiostatins/therapeutic use; Vitreoretinal surgery

Surgical complications of primary rhegmatogenous retinal detachment: a meta-analysis.

BackgroundTo investigate the surgical complications of scleral buckling (SB) and pars plana vitrectomy (PPV) performed on primary rhegmatogenous retinal detachment (RRD) and to discover which surgical procedures bring fewer complications.MethodsAn electronic literature search using the PubMed database, ISI Web of Knowledge and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials and observational studies comparing SB with PPV on primary RRD. Outcome measures included intra-operative complications and early and late post-operative complications.ResultsDuring the operation, significantly less subretinal hemorrhage occurred in the PPV group than in the SB group (OR = 4.71; 95%CI, 1.33–16.64; p = 0.02) and the hypotony incidence was significantly higher in the SB group (OR = 18.24; 95%CI, 2.37–140.44; p = 0.005); however, the occurrence of iatrogenic breaks was significantly lower in the SB group (OR = 0.05; 95%CI, 0.01–0.21; p<0.0001). In the early stage of post-operation, significantly higher incidence of choroidal detachment was identified in the SB group than in the PPV group (OR = 10.19; 95%CI, 2.36–44.09; p = 0.002); patients undergoing SB had significantly higher odds of residual subretinal fluid (OR = 14.71; 95%CI, 1.84–117.32; p = 0.01); the occurrence of high intraocular pressure was significantly lower in the SB group (OR = 0.46; 95%CI, 0.23–0.89; p = 0.02); and no significant difference was shown in the incidence of epithelia defect (p = 0.37) between the two groups. In the late stage of post-operation, the incidence of diplopia/extraocular muscle dysfunction was significantly higher in the SB group (OR = 4.04; 95%CI, 1.30–12.52; p = 0.02); and significantly less cataract was observed in the SB group (OR = 0.20; 95%CI, 0.14–0.30; p<0.00001); no significant difference was found in the incidences of cystoid macular edema (p = 0.65), macular pucker (p = 0.52), post-operative proliferative vitreoretinopathy (p = 0.73) and epiretinal membrane (p = 0.47) in other late post-operative complications.ConclusionsThis meta-analysis suggests that PPV could be considered as potential surgical management on primary RRD.

The Surgical Outcomes, Complications and Predictive Surgical Factors of Diabetic Retinopathy Vitrectomy in a Large Asian Tertiary Eye Center

Purpose: To evaluate the visual, anatomical outcomes, complications and the predictive preoperative and intraoperative factors of pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) in a large Asian tertiary eye center. Methods: This is a consecutive retrospective review of 106 eyes that underwent PPV for PDR complications in 2013. The functional success was defined as visual acuity of 20/200 or better while the anatomical success was defined as 360° flat retina without endo-tamponade at one year. Results: The overall functional and anatomical success was 77.4% and 94.3%, respectively. The common complications were iatrogenic break (14.2%), raised intraocular pressure (IOP) (13.2%), cataract (13.2%) and recurrent vitreous hemorrhage (12.3%). The use of intraoperative triamcinolone (OR: 0.36, p=0.04) and silicone oil (OR: 0.08, p<0.001) were associated with poorer visual success. The iatrogenic breaks occurred more often in 20G PPV than 23G PPV (OR: 5.89, p=0.02) whereas intraoperative silicone oil were associated with postoperative raised IOP (OR: 3.71, p=0.04). The use of bevacizumab was not found to reduce recurrent vitreous hemorrhage (OR: 0.53, 95%CI: 0.11-2.53, p=0.43). Conclusions: In the era of small gauge vitrectomy, the visual, anatomical outcomes and complication rates of PPV for PDR patients in Singapore had improved significantly, as compared to the Diabetic Retinopathy Vitrectomy Study.

Author′s Response: Maximizing the visual outcome in traumatic cataract cases: The value of a primary posterior capsulotomy and anterior vitrectomy

Dear Sir, First of all we are thankful to you for your interest and inputs. Primary posterior capsulotomy and vitrectomy procedure done in the absence of poster capsular tear is a special procedure by vitreo rhexis. It is not only to prevent capsular opacification, but to avoid secondary cataract and recurrent inflammation of anterior vitreous.[1,2] Erie et al. reported incidence of retinal detachment in case of the posterior capsular rent in case of normal cataract, this study is all about traumatic cataract so normal and post trauma cataracts are not comparable.[1,2,3] With the emergence of high speed vitrectomy machines and cutters, incidence of iatrogenic break and retinal detachment following shallow anterior vitrectomy is minimal.[4,5] Nd: YAG may cause may cause increase incidence of retinal break and retinal detachment.[6] The primary objective of this study was to study the effect of primary posterior capsulotomy on final visual outcome in the case of traumatic cataract.[1,2] It is important to have long-term follow-up, but this study is about traumatic cataract, trauma may have many co morbidities, which may also cause damage other than posterior capsulotomy.[2] We may follow-up these cases way forward for a longer period.

23-gauge sutureless vitreo-retinal surgery for superior rhegmatogenous retinal detachment.

To determine the results of 23-gauge sutureless vitreo-retinal surgery for superior/supero-temporal rhegmatogenous retinal detachment (RRD). Quasi experimental study. LRBT, Free Base Eye Hospital, Karachi, from January 2010 to December 2011. Adult patients who underwent 23-gauge sutureless vitreo-retinal surgery along with use of Perfluoropropane (C3F8) gas as internal tamponading agent for fresh (upto 3 weeks) superior/supero-temporal RRD was reviewed. Major outcome measures were anatomical success, best corrected visual acuity (BCVA) with Log Mar and complications during and after surgery. Postoperative follow-up was done on 1st day and at 1st, 4th, 8th and finally at 12th week. Sixty eyes of 60 patients, age between 30 - 60 years including 37 (61.67%) males and 23 (38.33%) females having superior or superatemporal RRD underwent 23-guage sutureless vitreo-retinal surgery with the use of perfluoropropane (C3 F8) gas as internal temponade at the end of procedure. Anatomical success rate was 81.66% (49 out of 60 eyes) with first surgery and raised to 90% (54 cases) with second surgery. Log Mar BCVA significantly improved from mean baseline 0.93 to 0.49 with mean difference of 0.43 (p < 0.001), 95% confidence interval. Postoperative complications were sub-conjunctival haemorrhage in 11 eyes (18.33%), wound leak in 7 eyes (11.66%), anterior chamber became shallow in 6 eyes (10%), cataract developed in 5 eyes (8.33%), re-retinal detachment in 4 eyes (6.66%), ocular hypotony and sterile inflammatory reaction in 3 eyes (5%) each, while iatrogenic breaks developed in 2 eyes (3.33%). The 23-gauge sutureless vitreo-retinal surgery for superior rhegmatogenous retinal detachment achieved high anatomical success and significant visual improvement. Sub-conjunctival haemorrhage was the most frequent procedural complication.

Clinical outcome of preoperative and intraoperative intravitreal injection of bevacizumab as an adjunct to vitrectomy in the treatment of proliferative diabetic retinopathy

Objective The aim of this study was to evaluate the safety and clinical efficacy of an intravitreal injection of bevacizumab in pars plana vitrectomy (PPV) for complicated proliferative diabetic retinopathy (PDR). Patients and methods The study included 20 eyes of 20 patients (25-68 years old) with complicated PDR. All patients underwent 23-G PPV, and all of them received an intravitreal injection of 1.25 mg bevacizumab 1 week before planned vitrectomy and at the end of surgery. Results The mean surgical time was 60.5 ± 20.2 min (range 40-95 min). Iatrogenic breaks were reported in four eyes (20%) and silicone oil was used in these cases (20%). Final visual acuity showed improvement in 17 eyes (85%), whereas postoperative best-corrected visual acuity remained unchanged in three eyes (15%). The mean preoperative corrected visual acuity was 1.47 ± 0.73 logMAR units. A statistically significant increase in the mean corrected visual acuity was observed in all study eyes at 3 months after surgery (0.60 ± 0.48 logMAR units; P Conclusion Injection of bevacizumab, 1.25 mg (0.05 ml), 1 week before PPV and at the end of operation is safe and effective, resulting in a decrease in the operation time, iatrogenic retinal breaks, intraoperative and postoperative bleeding, and improved visual acuity in PDR patients.

A comparative study of 23 G vitrectomy and bimanual surgery in the management of epiretinal membranes in diabetic eyes

PurposeThe purpose of the study was to compare the anatomical and functional outcome of the use of high-speed 23 G vitreous cutters shaving versus bimanual surgery in the management of epiretinal membranes (ERMs) in eyes with diabetic tractional retinal detachment (TRD).DesignProspective comparative double-blind study.SettingModern Ophthalmology Center, Alexandria, Egypt.Patients and methodsThe study was conducted on 60 eyes with diabetic TRD, divided blindly into two equal groups. Informed consent was obtained from all patients before participation in the study. Group I was operated upon with the Twinac cutter on Oertli OS3 NovitreX using the foot-controlled peristaltic pump. Group II was operated upon with a chandelier light using twinlight on BrightStar. The ERM was operated upon using curved 23 G scissors and end-gripping forceps. All eyes were followed up for 6 months after surgery.ResultsComplete removal of ERM was achieved in 20 (66.7%) eyes and 30 (100%) eyes, iatrogenic breaks in 10 (33.4%) eyes and five (16.7%) eyes, postvitrectomy bleeding in five (16.7%) eyes and two (6.7%) eyes, retinal tamponade was not needed in six (20%) eyes and eight (26.7%) eyes, in groups I and II, respectively. There was significant difference between the two groups in complete removal of ERM, use of gas or air as a tamponade, and use of silicone tamponade.ConclusionAlthough the advent of high-speed 23 G vitreous cutter facilitates dissection of ERM in eyes with diabetic TRD, bimanual surgery is associated with statistically significant more complete removal of ERM, more use of temporary tamponade as gas or air, and less use of silicone oil.

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.

Iatrogenic retinal breaks in 20-G versus 23-G pars plana vitrectomy

The purpose of this study was to compare the incidence of iatrogenic anterior retinal breaks in 20-G vitrectomy (PPV) with transconjunctival 23-G PPV. Retrospective, observational review study involving consecutive patients undergoing PPV in a single center in the UK during a 2-year period. Sclerotomy-related entry-site breaks (ESB) were found in 50/628 (7.9 %) 20-G PPV cases and 5/296 (1.7 %) 23-G PPV eyes (p<0.0001*). Anterior non-sclerotomy iatrogenic breaks (ANSB) were present in 55/628 (8.7 %) 20-G PPV cases and 18/296 (6.1 %) 23-G PPV eyes (p=0.19). The incidence of total anterior iatrogenic breaks (ANSB + ESB) was 105/628 (16.7 %) for 20-G PPV and 23/296 (7.8 %) for 23-G PPV (p=0.002*). Univariate analysis showed that posterior vitreous detachment induction was the only risk factor significantly associated with the development of anterior retinal breaks for both 20-G and 23-G PPV. Multivariate logistic model of risk factors for development of iatrogenic retinal breaks demonstrated that 23-G PPV was the most important factor reducing the risk of anterior breaks (p<0.0001*). We report the largest series of patients undergoing 20-G and 23-G vitrectomy, where 23-G vitrectomy was associated with a significantly lower incidence of anterior iatrogenic retinal breaks.

Risk factors for iatrogenic retinal breaks induced by separation of posterior hyaloid face during 23-gauge pars plana vitrectomy

To describe the incidence and features of intraoperative retinal breaks caused by induction of posterior hyaloid face (PHF) separation during 23-gauge pars plana vitrectomy (PPV). A prospective, consecutive, single surgeon, observational study of patients undergoing 23-gauge transconjunctival sutureless vitrectomy for macular pathology or floaters, was carried out between 2009 and 2011 at Calderdale Royal Hospital, UK. PHF separations were categorised as either suction induced or requiring membrane blue (DORC Limited) with suction (adherent). The outcome measure was dichotomised into retinal break or tear and no retinal break or tear. Forced entry and parsimonious multiple logistic regression analyses were conducted, using statistical software, to test for significance of association of the set of recorded factors and covariates with the dichotomised outcome measure. Data were collected and analysed from 137 patients. The incidence of iatrogenic retinal breaks associated with PHF separation during 23-gauge PPV was 18.2%. Under both forced entry and parsimonious multiple logistic regression models, the odds of a retinal break or tear reduce by about 3-4% for each increasing year of age. Findings also showed some substantive association in the forced entry model, with the odds of a retinal break or tear for adherent cases being around 3.8 times those for suction-only cases. Mechanical detachment of the PHF represents an important risk factor in the formation of retinal breaks. Particular care should be taken to examine intraoperatively for iatrogenic breaks in order to prevent missed breaks and subsequent rhegmatogenous retinal detachments.

The incidence and the risk factors for iatrogenic retinal breaks during pars plana vitrectomy

To establish the frequency and the risk factors for iatrogenic retinal breaks during three-port pars plana vitrectomy (PPV). A total of 2471 PPV operations were included in the study. The study period was between 2001 and 2010, all the data were entered in an electronic patient record database. All 270 consecutive eyes of 270 patients developing iatrogenic retinal breaks during primary PPV were matched to 270 controls. Univariate and multivariate analysis were performed to establish the risk factors. The median age of the patients with iatrogenic breaks was 60.06 years; male to female ratio was 140/130. The overall frequency of iatrogenic retinal breaks was 10.09%. The frequency of iatrogenic retinal breaks for eyes undergoing PPV for tractional retinal detachment (TRD) was 32.45%. The lens status was phakic in 79.6% of the eyes, with iatrogenic breaks compared with 34.4% of the eyes in control group (P<0.001). Posterior vitreous was attached in 58.9% of the eyes with iatrogenic breaks compared with 50.4% of the eyes in control group (P=0.04). Internal limiting, epiretinal, proliferative, or fibrovascular membrane removing manoeuvers were performed in 71.1% of the eyes with iatrogenic breaks compared with 61.9% of the eyes in control group (P=0.052). Eyes undergoing PPV for TRD had significantly higher frequency of iatrogenic retinal breaks compared with other subgroups (P=0.0001). Phakia and absence of PVD were found to be risk factors for iatrogenic retinal breaks.

The incidence and distribution of iatrogenic retinal tears in 20-gauge and 23-gauge vitrectomy

The development of 23-gauge vitrectomy surgery has many benefits including a reduction in surgical time and faster postoperative rehabilitation; however, some have suggested that the complication rate is higher. To assess this we compared the incidence and distribution of iatrogenic retinal tears in 20- and 23-gauge surgery. Fifty consecutive 23-gauge and 50 consecutive 20-gauge vitrectomy cases were selected; eyes with a history of previous vitreoretinal surgery were excluded. All surgery was performed by two surgeons (JL and RN). Entry-site breaks (ESB) were defined as any new vitreoretinal abnormality occurring within 1 clock hour of an entry site for which treatment with cryotherapy was deemed necessary. Data were collected by retrospective case note review. Statistical analysis was carried out using Fisher's exact and χ(2)-tests. ESB occurred in 24% (12/50) of cases in the 20-gauge group compared with 8% (4/50) in the 23-gauge group (P = 0.03); 88% (14/16) occurred superiorly on the same side as the surgeons' dominant hand. Iatrogenic breaks recorded elsewhere indicated an increased incidence in the 20-gauge group (9/50 compared with 6/50 in 23-gauge) but this did not achieve significance; the most common position was at 6 o'clock. 23-Gauge vitrectomy is associated with significantly fewer ESB when compared with conventional 20-gauge vitrectomy. The incidence of other iatrogenic breaks did not appear to be significantly different between the two groups.