Twenty-Three-Gauge Pars Plana Vitrectomy With Inferior Retinectomy and Postoperative Perfluoro-n-Octane Retention for Retinal Detachment Repair

Transcription

1 ORIGINAL CLINICAL STUDY Twenty-Three-Gauge Pars Plana Vitrectomy With Inferior Retinectomy and Postoperative Perfluoro-n-Octane Retention for Retinal Detachment Repair Ryan B. Rush, MD,* Matthew P. Simunovic, MB, BChir, PhD,Þ and Alex P. Hunyor, MB, BS(Hons), FRANZCO, FRACSÞþ Purpose: The objective of this article was to study outcomes following use of perfluoro-n-octane (PFO) as a short-term postoperative vitreous substitute in patients undergoing pars plana vitrectomy for a recurrent rhegmatogenous retinal detachment (RRD) with advanced proliferative vitreoretinopathy requiring an inferior retinectomy. Design: A retrospective consecutive chart review. Methods: The charts of subjects who underwent RRD repair by pars plana vitrectomy with short-term postoperative PFO, vitreous substitution were retrospectively reviewed. The primary outcome was the anatomic success rate following retinectomy and short-term PFO retention. The secondary outcomes were change in best corrected visual acuity (BCVA) and occurrence of complications related to short-term PFO retention. Results: The anatomic success rate at the final follow-up was 91.7% (11/12). A total of 7 (58.3%; confidence interval, 32%Y80.7%) of 12 patients achieved a final BCVA better than initial BCVA. There were no significant complications related to short-term PFO retention. Conclusions: Perfluoro-n-octane is efficacious and safe as a shortterm vitreous substitute for repair of a recurrent RRD with advanced proliferative vitreoretinopathy requiring an inferior retinectomy. Key Words: retinal detachment, inferior retinectomy, perfluoro-n-octane (Asia Pac J Ophthalmol 2013;2: 232Y236) Pars plana vitrectomy (PPV) with perfluoro-n-octane (PFO) utilization has improved the anatomic success rate for complex retinal detachment repair. 1 Perfluoro-n-octane reportedly has been helpful in facilitating intraoperative surgical maneuvers in patients with a giant retinal tear or proliferative vitreoretinopathy (PVR). 2,3 However, long-term postoperative vitreous substitution with PFO has not been recommended by researchers because of its potential to compress and disorganize the retina. 4 This potential consequence of PFO has been described as a physical effect rather than chemical toxicity and experimentally has depended on the magnitude of the PFO retained. Perfluoro-n-octane migration into the anterior chamber may be poorly tolerated and result in corneal edema within 48 to 72 hours. 5 Other reported adverse effects of PFO include intraocular lens opacification, increased intraocular pressure (IOP), and subretinal migration. 6Y8 Shortterm, postoperative PFO retention/vitreous substitution has been successfully utilized in retinal detachment surgery. 9Y11 From the *Southwest Retina Specialists, Amarillo, TX; and Sydney Eye Hospital, Sydney, and Retina Associates, Chatswood, New South Wales, Australia. Received for publication December 9, 2013; accepted April 8, The authors have no funding or conflicts of interest to declare. Corresponding Author: Ryan B. Rush, MD, Southwest Retina Specialists, 7411 Wallace Blvd, Amarillo, TX Ryanbradfordrush21@hotmail.com. Copyright * 2013 by Asia Pacific Academy of Ophthalmology ISSN: DOI: /APO.0b013e31829e74b3 Perfluoro-n-octane offers a distinct benefit over conventional vitreous substitutes such as sulfur hexafluoride, perfluoropropane, and silicone oil for inferior pathology retinal detachments by eliminating compulsory postoperative face-down positioning. Experimental research indicates that retinopexy with laser and cryotherapy creates a firm, adherent chorioretinal scar within 1 to 2 weeks. 12 Therefore, vitreous substitution with PFO may provide an effective short-term retinal tamponade to help improve the anatomic and visual outcomes of retinal detachments complicated by inferior PVR. In this study, we investigated the outcomes and complications of short-term, postoperative PFO vitreous substitution in patients who underwent PPV with inferior retinectomy for recurrent retinal detachment complicated by inferior PVR. MATERIALS AND METHODS The Sydney Eye Hospital institutional review board approved this retrospective chart review of patients who have rhegmatogenous retinal detachment (RRD) who underwent PPV with inferior retinectomy and postoperative PFO retention from January 2006 to August Eight vitreoretinal surgeons performed or supervised vitreoretinal fellows in all surgical procedures. Eligibility Criteria Patients were included if the following criteria were met: (1) PPV with postoperative PFO retention was performed for a recurrent RRD complicated by inferior PVR; (2) PVR was grade C or higher according to the classification recommended by Machemer and associates 13 ; (3) PVR occurred in the inferior 4 clock-hours (4:00Y8:00) of the retina and was 1 clock-hour or more in quantity; (4) a 180-degree inferior retinectomy was performed during the PPV procedure in which PFO was used as the vitreous substitute; and (5) at least 12 months of followup from the PFO removal procedure was documented. Exclusion criteria were as follows: (1) macular disease (macular degeneration, diabetic maculopathy, etc) before retinal detachment was clinically evident or had been previously documented; and (2) PPV with 180-degree inferior retinectomy was insufficient to intraoperatively reattach the retina, thereby requiring retinectomy of greater than 180 degrees. Surgical Technique and Postoperative Period All patients underwent a standard 3-port, 23-gauge PPV with the Accurus Surgical System (Alcon Inc, Fort Worth, Tex) and a wide-angle viewing system according to surgeon preference. If silicone oil or gas was present from a previous PPV, it was extracted and exchanged for fluid. All patients previously had undergone PPV for RRD repair, and a posterior vitreous detachment was verified using aspiration with an extrusion cannula with or without triamcinolone assistance. High-speed Asia-Pacific Journal of Ophthalmology & Volume 2, Number 4, July/August 2013

2 Asia-Pacific Journal of Ophthalmology & Volume 2, Number 4, July/August 2013 Retinectomy and PFO Retention TABLE 1. Initial Patient Characteristics Extension of PVR Clock-Hours of Inferior PVR Duration Between Primary Surgery and PFO Retention Surgery, d Patient Age and Sex Location of Primary Break(s) Total No. Surgeries Before Retinectomy/PFO Retention Primary Surgery Type Preoperative PVR Before Primary Repair Initial Macula Status Lens Status Patient 1 Off Pseudophakic Yes PPV/C3F8 1 Inferior 77, F 32 4 Up to mid equator 2 Off Pseudophakic No SB/SF6 1 Inferior 73, M 73 3 Up to vitreous base 3 Off Pseudophakic No PPV/SF6 1 Superior and inferior 59, F 12 4 Up to mid equator 4 On Phakic No PPV/C3F8 1 Inferior 55, F Up to vitreous base 5 Off Phakic No PPV/SF6 2 Superior and inferior 61, M 75 2 Up to mid equator 6 Off Phakic Yes PPV/SB/SF6 2 Temporal 58, F 90 4 Up to mid equator 7 Off Pseudophakic Yes PPV/C3F8 1 Inferior 72, M 15 3 Up to vitreous base 8 Off Pseudophakic No PPV/SF6 3 Superior 80, F 47 4 Up to mid equator 9 On Phakic No PPV/SF6 2 Inferior and temporal 57, F 21 4 Up to mid equator 10 Off Pseudophakic No PPV/C3F8 2 Superior and temporal 60, M 60 4 Up to mid equator 11 Off Pseudophakic No SB/SF6 1 Superior 84, M 90 2 Up to mid equator 12 Off Phakic Yes PPV/SB/SF6 3 Temporal 67, F 42 3 Up to mid equator SB indicates sclera buckling; C3F8, perfluoropropane; SF6, sulfur hexafluoride. vitreous cutting rates (2500 cuts/min) with low vacuum settings were applied. Membrane peeling was performed to remove all manifest preretinal and subretinal membranes. Following membrane peeling, persistent retinal shortening was confirmed by the occurrence of subretinal air during the air-fluid exchange. A 180-degree inferior retinectomy was then performed under air or fluid according to surgeon preference. Endodiathermy and/or increasing the infusion bottle height was used for hemostasis. The fluid or air was next exchanged for PFO, and the retina was successfully reattached. The retinectomy margin was treated with at least 2 confluent rows of endolaser photocoagulation. The PFO was retained to produce a 90% to 99% PFO vitreous cavity fill. The sclerotomies were sutured with 7-0 Vicryl. Patients were instructed to posture supine for 24 hours after which no specific posturing was advised. A staged secondary PPV to remove the PFO was scheduled 1 to 2 weeks later. At the time of the staged secondary PPV, PFO was exchanged for fluid, and the retina was carefully inspected. Additional endolaser photocoagulation re-enforcement was performed according to surgeon preference. A fluid-air exchange and subsequent vitreous substitution with 1000 centistoke silicone oil were performed in each patient. Care was taken to ensure that all PFO was removed from the eye. An anterior chamber paracentesis with cannula aspiration of PFO was performed in all patients where anterior chamber PFO migration occurred. Patients were not given any particular posturing requirement following PFO removal. Data Collection The data collected before and during the initial (primary) RRD repair procedure included the patient s best corrected visual acuity (BCVA), age, refractive status, lens status, type of procedure performed, vitreous substitute utilized, and the presence of preoperative PVR. The data collected after the failure of the primary RRD repair included the total number of attempted retinal detachment procedures before the PPV with PFO retention procedure, and the time from the primary RRD repair procedure until the PPV with PFO retention procedure was performed. The data collected between the PPV with PFO retention procedure and the PPV procedure to remove the PFO included the number of days between procedures, the IOP, the presence of PFO migration into the anterior chamber, the presence of PFO deposits on the posterior surface of the lens, the level of intraocular inflammation as scored according to Jabs and associates, 14 and other complications such as subretinal PFO migration, hypotony, or corneal decompensation. The data collected during and after the PPV with PFO/silicone oil exchange procedure included whether the retina remained reattached, the length of follow-up, and the final documented BCVA at 12 months following the PFO removal procedure. Outcome Measures The primary outcome measure of this study was the anatomic success or reattachment rate after 12 months follow-up from PFO removal. Anatomic success was defined as complete retinal reattachment at all times during and after the staged PFO removal procedure. The secondary outcomes included change in BCVA and occurrence of complications related to PFO retention. Statistical Analysis Statistical analysis was performed using the VassarStats statistical package ( Preoperative and postoperative BCVAs in logmar were compared using paired t test. Tests of significance were performed 2-tailed, and a P G 0.05 was considered statistically significant. Snellen visual acuity was converted into logmar values as developed by * 2013 Asia Pacific Academy of Ophthalmology 233

3 Rush et al Asia-Pacific Journal of Ophthalmology & Volume 2, Number 4, July/August 2013 TABLE 2. Outcomes Patient Redetachment Following PFO Removal Initial BCVA, m Final BCVA, m Total Follow-up, mo 1 No LP CF 24 2 No 6/90 6/ No 6/45 6/ No 6/6 6/ No HM 6/ No HM 6/ No 6/12 6/ Yes HM LP 24 9 No 6/9 CF No CF HM No CF 6/ No CF 6/60 24 HM, hand motions at 1 m; CF, count fingers at 1 m; LP, light perception. Ferris et al. 15 The logmar values of light perception visual acuity was assigned +4.0 logmar; hand movements visual acuity was assigned +3.0 logmar, and counting fingers visual acuity was assigned +2.0 logmar according to methods published by Holladay. 16 RESULTS A total of 12 patients from a cohort of 653 consecutive patients who had RRD repair performed at Sydney Eye Hospital during the period 2006 to 2008 met the inclusion criteria for our study. Initial patient characteristics are summarized in Table 1. Surgical outcomes and BCVA are summarized in Table 2. Complications related to PFO retention are summarized in Table 3. A total of 11 (91.7%; confidence interval [CI], 64.6%Y98.5%) of 12 patients achieved anatomical success following PPV, inferior retinectomy, and short-term PFO retention (mean, 10.3 [SD, 1.8] days). A total of 7 (58.3%; CI, 32%Y80.7%) of 12 patients achieved a final acuity that was better than presenting acuity, whereas acuity was worse in 5 (41.7%; CI, 19.3%Y68.1%) of 12 patients. There was no significant difference in preoperative and postoperative visual acuities (P = 0.22). The macula was detached in 10 of 12 patients on initial presentation and in 11 of 12 patients immediately before PPV, inferior retinectomy, and short-term PFO retention, and the macula was remained detached in 1 of 12 patients at last follow-up following the PFO removal procedure. Patient 4 was the only patient whose retinal detachment never involved the macula. Immediately before the PPV, inferior retinectomy, and shortterm PFO retention, a total of 7 of 12 patients had grade C PVR in all 4 of the inferior clock-hours, 3 of 12 patients had grade C PVR in 3 of the 4 inferior clock-hours, and 2 of 12 patients had grade C PVR in 2 of the 4 inferior clock-hours. A total of 10 of 12 patients required the 180-degree inferior retinectomy to extend from the mid equator to the ora serrata, whereas 2 of 12 patients required the 180-degree inferior retinectomy to extend from the vitreous base region to the ora serrata. Neither the extent of preoperative inferior PVR or amount of intraoperative retinectomy correlatedwiththefinalbcva(p =0.44andP = 0.35, respectively). None of the 12 study patients underwent scleral buckling at any time during the study (although buckling had been performed as a primary procedure in 4 patients). In terms of complications, 4 patients (33%; CI, 13.8%Y60.9%) developed deposits on the posterior surface of the lens, 2 (16.7%; CI, 4.7%Y44.8%) had PFO migration into the anterior chamber, 6 (50%; CI, 25.4%Y74.6%) had anterior chamber inflammation, and 3 patients (25%; CI, 8.9%Y53.2%) developed IOP of 21 mm Hg or greater. The 2 patients with the highest recorded IOP levels had PFO in the anterior chamber. Intraocular inflammation was managed successfully with topical steroids in all patients. There were no patients of subretinal PFO migration, hypotony, or corneal decompensation. None of the study patients experienced intraoperative hemorrhaging that could not be managed by endodiathermy and/or increasing the infusion bottle height. All 12 study patients underwent at least 1 spectral domain optical coherence tomography (OCT) examination more than 6 months after the PFO removal procedure. A total of 1 of 12 patients had persistent cystoid macular edema on OCT for more than 6 months following the PFO removal procedure, and a total of 5 of 12 patients were found to have an epiretinal membrane on OCT after the PFO removal procedure. DISCUSSION Recurrent retinal detachments following PPV with inferior retinectomy may be attributed in some instances to insufficient or unidirectional (superiorly directed) retinal tamponade with such vitreous substitutes as silicone oil or gas, especially if a TABLE 3. Complications (All Examinations to Evaluate for Complications Occurred 1 Day Before the PFO Removal Procedure) Patient PFO Retention Duration, d PFO Lens Deposits PFO in AC Postoperative IOP Inflammation Grade 1 8 No No No No Yes No No Yes No No Yes No No Yes No No No No Yes No No No Yes No 14 0 AC indicates anterior chamber * 2013 Asia Pacific Academy of Ophthalmology

4 Asia-Pacific Journal of Ophthalmology & Volume 2, Number 4, July/August 2013 Retinectomy and PFO Retention stringent posturing schedule is not followed. In most patients where PVR necessitates an inferior 180-degree retinectomy, strict face-down posturing for the first few days may be considered obligatory. If fluid is allowed access under the edge of the retinectomy margin before laser retinopexy has developed into a firm chorioretinal adhesion, the retina may redetach in the postoperative period. Retinal pigment epithelial cells as well as mediators of cellular proliferation tend to become concentrated in the residual aqueous fluid around the tamponading agent, which in the upright position lies inferiorly and in the supine position lies in close proximity to the entire retinal surface. Perfluoro-n-octane should in theory float these cells and mediators anteriorly off the retinal surface with supine posturing. Because most patients tolerate postoperative supine posturing much better than face-down posturing, PFO offers a significant advantage over both silicone oil and gas in this particular circumstance. Other theoretical advantages of postoperative perfluorocarbon liquid tamponade over silicone oil include a greater tamponading force due to its high specific gravity (PFO, 1.76) and its lower viscosity, making it easier to remove from the eye. However, postoperative silicone oil has better long-term tolerability compared with PFO, thereby requiring an additional procedure to exchange PFO for another vitreous substitute. Recurrent retinal detachment rates of 15% to 45% with or without scleral buckling have been reported in complex retinal detachment patients when intraoperative PFO and postoperative silicone oil or gas tamponade was used. 1,17,18 However, recurrent retinal detachment rates of only 6% to 22% have been reported in complex retinal detachment patients when postoperative PFO was retained for 5 to 14 days. 9Y11 This is the first study to directly evaluate short-term postoperative PFO retention in recurrent retinal detachment patients with advanced PVR requiring extensive inferior retinectomy. The recurrent retinal detachment rate in this study compares favorably with the results of these other studies evaluating complex retinal detachments. A recent retrospective study of 12 eyes with inferior retinal detachments reported an anatomic success rate of 76% following short-term postoperative PFO retention (3Y11 days) with a mean follow-up of 14 months. 19 Five of the patients in that study had inferior PVR present, but only 1 patient underwent retinectomy. Our study compares favorably to this report, demonstrating a 91.7% (11/12) anatomic success rate. Most of the patients in this study experienced improved BCVA following reattachment with retinectomy and short-term PFO retention. Patients 8, 9, and 10 had multiple recurrent detachments involving the fovea before successful reattachment with retinectomy/pfo retention, likely accounting for the final BCVA level being worse than the initial level secondary to photoreceptor damage (IS/OS junction disruption evident on OCT). Patient 4 lost only 1 line of BCVA after successful retinal reattachment secondary to a mild postoperative epiretinal membrane (evident on OCT), but still retained excellent BCVA at 6/9. Patient 7 had persistent cystoid macular edema for more than 6 months, likely responsible for the final BCVA level being worse than the preoperative level secondary to photoreceptor damage (IS/OS junction disruption evident on OCT). Patients 2, 3, 5, and 11 experienced a remarkable recovery of BCVA following retinectomy and short-term PFO retention. The safety of postoperative PFO tamponade and its superiority to other perfluorocarbon liquids including perfluoroperhydrophenanthrene and perfluorodecalin have been confirmed by previous studies. 1Y5,20 The development of postoperative complications in this study was similar in most respects to previous studies in which short-term postoperative PFO tamponade was used. 9Y11 Postoperative intraocular inflammation was mild and managed in all patients with topical anti-inflammatory therapies alone. There were no patients in which the intraocular inflammation was felt to exceed the usual amount of postoperative inflammation. In the 1 patient who had a postoperative increase of IOP greater than 25 mm Hg, the IOP was managed with topical medications alone. The presence of macroscopically visible PFO in the anterior chamber was found in the case associated with the IOP increase. It can be assumed that mechanical blockage of the trabecular meshwork by PFO globules rather than inflammatory cells, fibrin, or debris was most likely responsible for this finding. The patient s lens status did not determine whether PFO ultimately made its way into the anterior chamber, suggesting that PFO can permeate through intact zonules. There were not any cases of subretinal PFO, corneal decompensation, or hypotony in this study. Unlike the findings presented in another study, 11 this study did not find that PFO retention for 10 or more days significantly increased macrophage deposits on the lens capsule. Recently, Sigler et al 21 reported higher rates of postoperative PFO retention complications compared with this and other previous studies, including persistent IOP elevation in 34%, excessive inflammation in 27%, and PFO in the anterior chamber in 21%. However, the study of Sigler et al 21 retained PFO on average 1 week longer than our study. This suggests that PFO retention greater than 2 weeks may significantly increase the risk of PFO-related complications and may not add any additional benefits given that laser retinopexy creates a firm, adherent chorioretinal scar within 7 to 10 days. 12 Five of the 12 patients (41.67%; 95% CI, 19.33%Y68.05%) in this study developed an epiretinal membrane, which is higher incidence than that encountered for subjects with recurrent retinal detachment at our own institute (14/108 [12.96%; 7.88%Y20.59%]) (R.R.B., S.M.P.; Pars plana vitrectomy versus combined pars plana vitrectomy-scleral buckle for secondary repair of retinal detachment. Ophthalmic Surg Lasers Imaging; accepted for publication, February; 2013). This study suggests that PFO is a safe and effective vitreous substitute for short-term postoperative retinal tamponade in retinal detachments complicated by PVR requiring an inferior retinectomy. In fact, short-term postoperative PFO retention may even be more effective than postoperative silicone oil or long-acting gas tamponade in the prevention of recurrent retinal detachment in these high-risk cases. Weaknesses of this study include the small number of cases and the retrospective data collection. A larger randomized controlled trial is needed to further compare the safety and efficacy of short-term postoperative PFO tamponade with postoperative silicone oil and gas tamponade for retinal detachment repair. REFERENCES 1. Scott IU, Murray TG, Flynn HW Jr, et al. Outcomes and complications associated with perfluoro-n-octane and perfluoroperhydrophenanthrene in complex retinal detachment repair. Ophthalmology. 2000;107: 860Y Scott IU, Murray TG, Flynn HW Jr, et al. Perfluoron Study Group. Outcomes and complications associated with giant retinal tear management using perfluoro-noctane. Ophthalmology. 2002;109: 1828Y Scott IU, Flynn HW Jr, Murray TG, et al. 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