Hrev_master [Eye Reports 2011; 1:e3] [page 5] Outcomes of 23-gauge pars plana vitrectomy in combined scleral buckling and vitrectomy for complex rhegmatogenous retinal detachments Scott D. Schoenberger,1 Daniel M. Miller,1,2 Christopher D. Riemann,1,2 Robert E. Foster,2 Michael R. Petersen2 1Department of Ophthalmology, University of Cincinnati; 2Cincinnati Eye Institute, Cincinnati, Ohio, USA Abstract Rhegmatogenous retinal detachments asso- ciated with proliferative vitreoretinopathy, giant retinal tears, ocular trauma, proliferative diabetic retinopathy, or necrotizing retinitis are considered more complex than those with- out these factors. The aim of the current review is to address the surgical outcomes and complications of 23-gauge pars plana vitrecto- my with scleral buckling (23GPPV/SB) for repair of these complex retinal detachments. This retrospective study involved 54 eyes of 53 patients who underwent 23GPPV/SB between July 2007 and September 2009. Preoperative diagnosis, surgical technique, preoperative and postoperative visual acuities, intraopera- tive and postoperative complications, and anatomic reattachment rates were examined. Fifty-four eyes of 53 patients were reviewed in this study and indications for surgery varied. Mean logarithm of the minimal angle of reso- lution�(logMAR) pre- and post-operative visu- al�acuities were 1.166 (20/293) and 0.780 (20/120), respectively, which led to a statisti- cally significant improvement in logMAR (P=0.0165). Single operation and final reat- tachment rates were 87% (47 of 54 eyes) and 100%, respectively. Postoperative complica- tions included choroidal effusion/hemorrhage (14.8%, 8 of 54 eyes) and vitreous hemorrhage (11.1%, 6 of 54 eyes). Other more infrequent complications included hyphema (9.3%, 5 of 54 eyes), hypotony (5.6%, 3 of 54 eyes) and ocular hypertension > 35 mmHg (3.7%, 2 of 54 eyes). A total of 31.5% (17 of 54 eyes) of patients had a complication in the postoperative time peri- od, but 58.8% of these resolved spontaneously without requiring an intervention. 23GPPV/SB may be considered for complex retinal detach- ment repair with good anatomic reattachment rates, but with relatively high complication rates. Introduction Advancements in surgical instrumentation have led to changes in the surgical repair of rhegmatogenous retinal detachments (RRDs). Key components of RRD repair include pars plana vitrectomy (PPV), scleral buckling proce- dure (SBP), intraocular gas and silicone oil (SO) infusion, endolaser photocoagulation, perfluorocarbon liquids, and wide-angle view- ing systems.1-4 The evolution of smaller gauge vitrectomy instruments has been a significant technological advance in vitreoretinal surgery. There has been a trend towards the use of smaller gauge vitrectomy instruments to treat increasing complex posterior segment patholo- gy.5-7 Twenty three- and 25-gauge instruments have been used in primary pseudophakic reti- nal detachment repair.8 There have also been reports of their use in more complex retinal detachments requiring silicone oil.9,10 There is a spectrum of pathology in the treatment of RRDs. Generally, RRDs associated with proliferative vitreoretinopathy (PVR), giant retinal tears (GRT), ocular trauma, pro- liferative diabetic retinopathy (PDR), or necro- tizing retinitis are considered more complex than RRDs without these factors.11 Many vitre- oretinal surgeons would manage these more complex cases utilizing 20-gauge pars plana vitrectomy, and in many instances, with com- bined scleral buckling.12-18 However, the man- agement of complex RRDs varies by surgeon preference and experience. The aim of this retrospective study was to examine the anatomic success, visual out- comes, and complications of patients with complex RRDs treated with 23-gauge pars plana vitrectomy with scleral buckling (23GPPV/SB). Indications for surgery in this review included RRDs associated with PVR (any grade), GRT, ocular trauma, high myopia and multiple tears. Materials and Methods Patients who underwent 23-gauge PPV with SBP between July 2007 and September of 2009 by one of four surgeons at the Cincinnati Eye Institute were retrospectively identified. All patients provided preoperative informed con- sent for surgery. After the final follow up visit for each patient, data were retrospectively reviewed and were collected in accordance with compliance guidelines set forth by the Health Insurance Portability and Accounta - bility Act of 1996. Institutional review board (IRB) approval was obtained from the University of Cincinnati IRB prior to data col- lection. All patients undergoing 23GPPV/SB between the time frames mentioned above with at least one month of follow-up were included in the study. All patients underwent either local anesthe- sia with monitored anesthesia care and retrobulbar anesthesia or general anesthesia. The periocular skin was prepared with 5% povidone-iodine followed by a drop of povi- done-iodine in the inferior fornix. The eye was prepared and draped in standard fashion and a lid speculum was placed. A 360-degree encircling scleral buckle was placed using standard techniques. The site of all breaks was identified with indirect ophthalmoscopy and scleral depression. The buckle was posi- tioned to support the identified breaks and/or vitreous base. A #42 band or #41 band (Labtician, Oakville, Ontario, Canada) was sutured into position utilizing 5-0 nylon hori- zontal mattress sutures and the buckle was opposed with a Watzke sleeve (Labtician). The buckle was raised to a moderate height prior to proceeding with vitrectomy. Simultaneous clear corneal cataract surgery was performed by the vitreoretinal surgeon using standard phacoemulsification techniques in three of the cases. A 10-0 nylon suture was placed in the corneal incision at the conclusion of the cataract surgery. All PPV and cataract surgery was performed utilizing the Accurus® Vitreoretinal Surgical System (Alcon Laboratories Fort Worth, TX, USA) and either Xenon (Alcon) or Photon (Synergetics, O’Fallon, MO, USA) light sources. The trocar/cannula system (Alcon) was used to place 23-gauge cannulas in the superonasal, superotemporal and inferotem- poral quadrants. The trocar/cannula incisions were made in a beveled fashion through bare Eye Reports 2011; volume 1:e3 Correspondence: Daniel M. Miller, 1945 CEI Drive, Cincinnati, OH 45242, USA. Tel. +1.513.984.5133 - Fax: +1.513.984.2390. Email: dmiller@cincinnatieye.com Key words: pars plana vitrectomy, scleral buck- ling, complex rhegmatogenous retinal detach- ment. Conflict of interest: the authors report no con- flicts of interest. Contributions: all the authors contributed equally. Received for publication: 17 April 2011. Accepted for publication: 24 June 2011. This work is licensed under a Creative Commons Attribution NonCommercial 3.0 License (CC BY- NC 3.0). ©Copyright S.D. Schoenberger et al., 2011 Licensee PAGEPress, Italy Eye Reports 2011; 1:e3 doi:10.4081/eye.2011.e3 Non -co mmerc ial us e o nly [page 6] [Eye Reports 2011; 1:e3] sclera. The conjunctiva had been previously recessed during the peritomy for scleral buck- ling. Cannulas were placed inferotemporally, superotemporally, and superonasally 3 mm posterior to the limbus for pseudophakic eyes and 4 mm for phakic eyes. The infusion line was connected to the inferotemporal cannula. Wide-angle fundus visualization was achieved using either the BIOM noncontact wide field imaging system (Oculus, Munich, Germany) or the AVI contact panoramic viewing system (Advanced Visual Systems Inc., NY, NY, USA). The surgical procedures varied slightly depending upon the location and extent of the retinal detachment and the individual prefer- ences of the four surgeons. Generally, a core vitrectomy was performed followed by meticu- lous peripheral vitreous dissection with par- ticular attention to relieving all traction at the sites of retinal breaks and along detached reti- na. Scleral depression was performed when necessary. In many cases, Perfluoron (Alcon) was utilized to stabilize detached retina and facilitate egress of subretinal fluid through peripheral retinal breaks. Membrane peeling was performed using end-grasping forceps. Retinectomy was performed in some cases utilizing either the vitreous cutter or intraoc- ular scissors. A fluid-air exchange with a soft tip extrusion needle with active suction or the vitreous cutter itself was used to drain sub- retinal and posterior pole fluid. A directional endolaser (Synergetics) and/or laser indirect ophthalmoscope was utilized to demarcate retinal breaks and in some cases to perform 360 degree laser or demarcate a retinectomy border. Nonexpansile mixtures of either per- fluoropropane (C3F8) or sulfur hexafluoride (SF6) were used, and in many cases, 5000 centistoke silicone oil (Bausch and Lomb, San Dimas, CA, USA) was utilized for tamponade. At the conclusion of each procedure, the sclerotomies were closed with 7-0 vicryl sutures for many of the patients. The overly- ing conjunctiva was closed with 6-0 plain gut suture. Subconjunctival antibiotic and dexam- ethasone was administered. Ciloxan oph- thalmic ointment was placed on the surface of the eye followed by a patch and shield. Patients were instructed to position either face down or one side down for on average 7 days. Patient medical records were reviewed. Age, gender, eye, ophthalmic history, pre- and post-operative Snellen visual acuities, surgery data, intra- and post-operative complications, final attachment rates and need for subse- quent retinal detachment repair were obtained. Length of follow up was also record- ed. A total of 54 eyes in 53 patients were iden- tified. One male patient underwent surgery on both eyes during the course of the study; one eye had a RRD with high myopia and the other eye had a GRT. With the exception of patient gender, all statistical analysis and percentages were in reference to the number of eyes. Snellen visual acuities were converted to logMAR values for statistical analysis using the following equation: logMAR = - log (visual fraction). LogMAR acuities were converted back to Snellen visual acuities for reporting mean preoperative and postoperative visual acuities. For visual acuities worse than 20/400, visual function was recorded as count fingers (CF), hand motion (HM) or light per- ception (LP). No patients had no light percep- tion vision pre or postoperatively. LogMAR val- ues were assigned as 2.0 (CF vision), 2.3 (HM vision) or 2.6 (LP vision), as has been used in other studies.19-20 A student’s t-test with a 5% level of significance was used to determine if there was a statistical difference in the pre and postoperative logMAR visual acuities, and to compare postoperative complication rates among those with silicone filled eyes versus gas filled eyes. Results Patient demographics are summarized in Table 1. There were 54 eyes of 53 patients who underwent 23GPPV/SB. Mean age of the 54 eyes was 53.96 years (range of 18-88 years, standard deviation of 15.33). Right eyes were affected in 48.1% (26 of 54 eyes), while left eyes were affected in 51.9% (28 of 54 eyes). 41 of 53 patients (77.4%) were males, while the remaining 12 patients (22.6%) were females. One male patient underwent surgery on both eyes during the study. The mean follow up time for each eye was 8.96 months (standard deviation 5.61, range 1 to 23 months). The indications for surgery included the fol- lowing: RRD with any grade of PVR (15 of 54 eyes, 27.8%), multiple breaks associated with RRD (13 of 54 eyes, 24.1%), GRT (9 of 54 eyes 16.7%), high myopia (8 of 54 eyes, 14.8%), trauma (4 of 54 eyes, 7.4%), and other (5 of 54 eyes, 4.8%). Lens status was as follows: 37.0% of eyes were phakic (20 of 54 eyes), 59.3% were pseudophakic (32 of 54 eyes), one was aphakic (1.9%) and one had an anterior cham- ber intraocular lens (1.9%). Fifteen of 54 eyes (27.8%) had undergone a prior pars plana vit- rectomy. Table 2 summarizes surgical techniques and intraoperative variables. A 360-degree encircling scleral buckle was placed in all eyes. The number of eyes with simultaneous cataract extraction was three of 54 (5.6%) and one eye underwent a retinectomy at the time of surgery. The most commonly used tam- ponading agent was SF6 (61.1%, 33 of 54 eyes), with silicone oil (24.1%, 13 of 54 eyes) and C3F8 (14.8%, 8 of 54 eyes) used less fre- quently. The vast majority of eyes had a 42 band placed (88.9%, 48 of 54 eyes) as opposed to a 41 band (11.1%, 6 of 54 eyes). Perfluoro- n-octane (PFO) was used in 66.7% of eyes (36 of 54 eyes). All sclerotomies were left open in three eyes and a portion was left open in four eyes. All 23-gauge sclerotomy incisions were closed with a single interrupted 7-0 vicryl suture in the majority of cases (47 eyes). Visual outcomes, anatomic success and Article Table 1. Patient demographics. Gender Number of patients (%) Male 41 (77.4)* Female 12 (22.6) Age of 54 eyes Mean 53.96 years Standard deviation 15.33 Follow up time of 54 eyes Mean 8.96 months Standard deviation 5.61 Number of eyes (%) Eye involved Right 26 (48.1) Left 28 (51.9) Diagnosis RRD with PVR 15 (27.8) Multiple tears 13 (24.1) GRT 9 (16.7) Myopia 8 (14.8) Traumatic 4 (7.4) Other 5 (4.8) Prior PPV Yes 15 (27.8) No 39 (72.2) Lens Status Phakic 20 (37.0) Pseudophakic 32 (59.3) ACIOL 1 (1.9) Aphakic 1 (1.9) *One male patient had surgery on both eyes. RRD, rhegmatogenous retinal detachment; PVR, proliferative vitreoretinopathy; GRT, giant retinal tear; ACIOL, anterior chamber intraocular lens. Table 2. Intraoperative features. Number of eyes (% of eyes) Additional step Retinectomy 1 (1.9%) Cataract extraction 3 (5.6%) PFO 36 (66.7%) Intraocular tamponade SF6 33 (61.1%) C3F8 8 (14.8%) Silicone Oil 13 (24.1%) Band Placed 41 6 (11.1%) 42 48 (88.9%) PPV, pars plana vitrectomy; PFO, perfluoro-n-octane. Non -co mmerc ial us e o nly [Eye Reports 2011; 1:e3] [page 7] complications are summarized in Table 3. Mean logMAR preoperative visual acuity was 1.166 (20/293) with a standard deviation of 0.941. Mean logMAR postoperative visual acu- ity was 0.780 (20/120) with a standard devia- tion of 0.685. Visual acuity significantly improved by 0.386 logMAR units (P=0.0165). The anatomic reattachment rate was 87.0% after one operation (47 of 54 eyes), with all eyes ultimately remaining attached. Seven eyes developed recurrent retinal detachment (rhegmatogenous and/or tractional) and required additional surgery. Six were due to PVR and one was related to a choroidal hemor- rhage. Two eyes required a third retinal detachment repair. Additional postoperative complications other than recurrent retinal detachment were common in this series reflecting the complex- ity of the underlying pathology. As listed in table 3, complications were separated based on when they presented clinically: intraoperative/ immediate (postoperative day one) or delayed (postoperative day two or beyond). Choroidal effusion or hemorrhage occurred in 8 of 54 eyes (14.8%). Five eyes had an intraoperative or immediate choroidal effusion or hemor- rhage. Only one of the eight eyes with a choroidal effusion or hemorrhage had co- existing hypotony. Vitreous hemorrhage occurred in 6 eyes (11.1%), of which two were immediate and resolved spontaneously. Three of four eyes with a delayed vitreous hemor- rhage occurred in eyes that re-detached and required additional surgery. A hyphema occurred in five eyes (9.3%). Delayed hyphe- mas (three of five eyes) resolved spontaneous- ly, but the two eyes with immediate hyphemas also developed vitreous and suprachoroidal hemorrhages. Hypotony occurred in three of 54 eyes (5.6%). It resolved spontaneously in two eyes, but one eye also developed a choroidal hemorrhage, hyphema, vitreous hemorrhage, and ultimately required a second retinal detachment repair. Ocular hypertension with an intraocular pressure greater than 35 mmHg occurred on POD1 in 2 of 54 eyes (3.7% of eyes), but resolved by the next postoperative visit. A total of 17 eyes (31.5%) had one of these complications at some point during the intraoperative or postoperative course, but over half of these (59.9%) resolved without any intervention. Two patients had at least four complications, including hyphema, vitreous hemorrhage, choroidal hemorrhage and a reti- nal detachment. They attained final Snellen visual acuities of 20/200 and 20/400. There was a nonsignificant trend towards decreased com- plications in silicone filled eyes (15.4% versus 36.6% in gas filled eyes, P=0.157). Discussion Prior studies have described complex rheg- matogenous retinal detachments as those that have included PVR, GRT, ocular trauma, high/pathologic myopia, PDR, and necrotizing retinitis.11 Surgeon preference influences the surgical approach to more complex pathology. Many surgeons would consider combined scle- ral buckling and 20-gauge PPV for these cases.15-18,21-24 A recent trend in vitreoretinal surgery has been the application of smaller gauge vitrecto- my instruments for increasing complex retinal pathologies. Twenty three-gauge PPV has been shown to be associated with more rapid visual recovery than traditional 20-gauge PPV in epiretinal membrane surgery.25 Others have used 23-gauge PPV for a multitude of posterior segment pathology with few complications and improved visual acuity.26-28 Given the recent lit- erature supporting the use of smaller vitrecto- my instruments with a good visual outcome and safety profile, the goal of the current review was to describe results using 23-gauge pars plana vitrectomy in combination with scleral buckling in these complex retinal detachment repairs. The main outcome measures included pre- operative and postoperative visual acuities, postoperative complications, and anatomic success. Visual acuities were significantly bet- ter postoperatively. Preoperative Snellen acuities averaged about 20/300 and postopera- tively were about 20/120. The role of induced corneal astigmatism by surgery was not addressed in this study, but prior studies have shown this to be less of an issue in those undergoing 23-gauge PPV as compared to 20- gauge PPV.25 Surgically induced corneal astig- matism is unlikely to be a critical factor in patients with complex RRDs and generally poor postoperative visual acuity results. However, a large proportion of patients with complex rhegmatogenous RRD do achieve good visual acuities and PPV-induced astigma- tism may be a factor in their visual rehabilita- tion. Immediate and delayed complications were not uncommon, as nearly one third of patients had a hyphema, ocular hypertension or hypotony, choroidal effusion or hemorrhage, vitreous hemorrhage or retinal detachment at some point in the postoperative period. The most common complications were choroidal effusions/hemorrhages and vitreous hemor- rhages. One hypothesis is that there may be transient hypotony postoperatively in these cases. This may occur even when 23-gauge sclerotomy sites are closed with 7-0 vicryl sutures. The trocar system used in this series produces an irregular t-shaped sclerotomy site even when made in a beveled fashion and thus may not close completely as with a linear 20- gauge incision. Several patients also had other risk factors for transient hypotony, including high myopia and prior pars plana vitrectomy. Overall, postoperative complications (with the exception of recurrent retinal detachment) were generally self-limited and did not affect final anatomic result or visual acuity results. The complication rates reported in this study are higher than those previously pub- lished by others for 20 gauge PPV with scleral buckling. Wickham et al.22 and Gartry et al.14 reported vitreous hemorrhage in approximate- ly 5-7% and choroidal hemorrhage in 4% of patients undergoing combined 20-gauge PPV with scleral buckling. However, the inclusion and exclusion criteria were different from the current review. In the former,22 patients were excluded if they had prior PPV, had grade C or greater PVR or GRTs. The latter article14 reviewed cases of relatively uncomplicated RRD, excluding GRTs and more advanced PVR. Albrieux et al. compared 23-gauge PPV to 20 gauge PPV for RRD repair.29 They found a sim- ilar rate of postoperative complications and anatomic reattachment among the two groups. While the rate of complications was lower than the current review (one choroidal detachment in the 23 gauge group, no hypotony, no report- ed vitreous hemorrhage or hyphema), SBP was not performed, and patients were excluded if Article Table 3. Visual outcomes and complica- tions. Mean preoperative visual acuity Snellen 20/293 LogMAR 1.166 Mean postoperative visual acuity Snellen 20/120 LogMar 0.780 LogMAR improvement 0.386 Number of eyes (% of eyes) Anatomic Success After one surgery 47 (87.0) After two surgeries 52 (96.3%) Final 54 (100%) Immediate or intraoperative complications Ocular hypertension 2 (3.7%) Hypotony 1 (1.9%) Hyphema 2 (3.7%) Vitreous hemorrhage 2 (3.7%) Choroidal effusion/hemorrhage 5 (9.3%) Delayed complications (Prestenting POD2 and beyond) Ocular hypertension 0 (0.0%) Hypotony 2 (3.8%) Hyphema 3 (5.6%) Vitreous hemorrhage 4 (7.4%) Choroidal effusion/hemorrhage 3 (5.6%) Number of eyes 17 (31.5%) with any complication VA, visual acuity; logMAR, logarithm of the minimal angle of resolu- tion; POD2, postoperative day 2. Non -co mmerc ial us e o nly [page 8] [Eye Reports 2011; 1:e3] they had prior PPV, traumatic RD, PVR grade C, GRTs, among other exclusion criteria. In the current review, patients had an anatomic reattachment rate of 87% after one surgery, but reached final reattachment in all cases. The reattachment rates in this study were similar to those reported by others for more complex retinal detachments.10,12,14,15,22 Single operation reattachment rates were lower than those reported by Stangos et al. (92.3%) and Weichel et al. (94%), but these patients underwent 20 gauge PPV with SBP for pseudophakic RRDs without associated PVR or GRT.13,28 The anatomic reattachment reported by Albrieux et al. for PPV without SBP was 74.3% (20 gauge group) and 80% (23 gauge group).29 The anatomic reattachment rate in the current review was similar to another study comparing 20 (89.3%), 23 (88.9%) and 25 gauge PPV (93.3%) without SBP for pseudophakic RRDs in patients without prior PPV.30 There are significant limitations to this ret- rospective study. First, the sample size is fairly small and indications for surgery were vari- able. Also, there are a large number of con- founding variables that were present, includ- ing a history of prior PPV, gas or silicone used for intraocular tamponade, use of PFO, closure of sclerotomies and simultaneous cataract extraction or retinectomy. Certainly, some of these variables might play a role in the single operation reattachment rates and the develop- ment of postoperative complications. The potential advantages of 23GPPV/SB sur- gery versus 20-gauge includes smaller sclero- tomy size, cannula based infusion line place- ment (versus suture fixation), and possibly reduced astigmatism. In the past, smaller gauge surgeries for more complex detach- ments have been limited due to reduced instrument rigidity and a reduced armamen- tarium of instruments (e.g. scissors). However, a wider array of ancillary instru- ments is available and 23-gauge PPV instru- ments have significant rigidity allowing com- plete eye rotation/control and dissection of dense fibrovascular tissue. Recent studies have shown similar flow rates between 23- and 20-gauge instruments thus enabling high vac- uum based maneuvers.31,32 Eventually, when a 23-gauge fragmotome for lensectomy is pro- duced, the 23-gauge platform may replace 20- gauge PPV in most cases. In summary, we conclude that 23-gauge pars plana vitrectomy with scleral buckling is a viable alternative to the traditional 20-gauge pars plana vitrectomy with scleral buckling. Our retrospective study shows a significant improvement in visual acuity after surgery, with a high single operation reattachment rate and a final reattachment rate of 100%. However, our study did show that postoperative complications (especially vitreous hemorrhage and choroidal effusion/hemorrhage) are high- er than those reported in some prior stud- ies14,22 and that these complications need to be further studied. It is unknown whether the higher complication rate is related to the 23 gauge platform or a difference in patient popu- lation, with more complex PVR, ocular trauma, and GRTs included in the current review. Ideally, a study to compare traditional 20-gauge PPV with scleral buckling and 23-gauge PPV with scleral buckling would help elucidate whether or not these complications are related to smaller gauge vitrectomy instruments and incisions, or related to the highly complex nature of retinal detachment repair in these patients. References 1. Brazitikos PD, D’Amico DJ, Tsinopoulos IT, Stangos NT. Primary vitrectomy with per- fluoro-n-octane use in the treatment of pseudophakic retinal detachment with undetected retinal breaks. Retina 1999;19: 103-9. 2. McCuen BW 2nd, Landers MB 3rd, Machemer R. The use of silicone oil fol- lowing failed vitrectomy for retinal detach- ment for advanced proliferative vitreo- retinopathy. Ophthalmology 1985;92:1029- 34. 3. 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