Original Manuscript Short- and Long-Term Outcomes of Vitreoretinal Surgeries With Deferred First Postoperative Visits at Day 3 or Later Journal of VitreoRetinal Diseases 2017, Vol. 1(2) 126-132 ª The Author(s) 2017 Reprints and permission: sagepub.com/journalspermissions.nav DOI: 10.1177/2474126416685632 jvrd.sagepub.com Vincent Y. Ho, MD, 1 and Gaurav K. Shah, MD 1 Abstract Background and Objective: Postoperative (PO) day 1 visits can be challenging for certain patients (eg, satellite office patients). This study analyzes the proportion of eyes requiring changes in management on the first PO visit day 3 following vitreoretinal surgery. Study Design/Materials and Methods: A retrospective, consecutive case series of 1 vitreoretinal surgeon was conducted on 246 surgeries of 231 patients with the first PO examination day 3 from January 1, 2008 to December 31, 2013. Clinical parameters were statistically analyzed to identify eyes with pressure issues or early interventions. Short- and long-term outcomes were assessed at PO weeks 1 to 4 and months 3 to 8. Results: At the first PO visit 3 (mean 4.5) days, 3.3% eyes had intraocular pressure (IOP) 5, 3.3% IOP 30, 0.8% choroidal detachments, 0.4% vitreous hemorrhage, and 0% endophthalmitis. About 2.0% of eyes required intervention (IOP medications). Surgical indications, procedure, and tamponade were not predictive of pressure issues or early intervention (P >.05). At weeks 1 to 4 and month 3 to 8, 4% to 6% of eyes required additional intervention or surgery. Conclusion: The first PO visit day 3 after vitreoretinal surgeries had low intervention rates. Few complications or additional surgeries occurred throughout the study period. Keywords vitreoretinal surgery, small-gauge vitrectomy, postoperative care, transconjunctival sutureless vitrectomy Introduction The majority of patients undergoing vitreoretinal (VR) surgery used to be admitted as inpatients. 1 With improvements in anesthesia (local anesthesia) and VR surgery equipment/ techniques, this was supplanted by postoperative (PO) day 1 visits. 2,3 There are many PO management concerns on the first day after VR surgery which include elevated intraocular pressure (IOP), hypotony, choroidal detachments, endophthalmitis, corneal epithelial defects, inflammation, and so on. However, as VR surgical techniques have evolved to smaller gauges, transconjunctival sutureless vitrectomy, more advanced vitrectomy platforms, and better instrumentation, more than one-third of the surveyed VR surgeons in the United Kingdom in 2011 see their PO patients at day 2 or later. 4 A similar paradigm shift occurred as cataract surgery transitioned from extracapsular cataract extraction to phacoemulsification. Numerous studies have cited low PO day 1 intervention rates after uncomplicated cataract surgery so omitting the PO day 1 visit was deemed justifiable. 5-10 In addition, since intervention rates are low, reports have also shown that PO day 1 care after cataract surgery can even be effectively managed by other health-care professionals such as optometrists or ophthalmic nurse practitioners 5,9,11 or via phone calls by nursing staff. 12 There are benefits to seeing VR surgical patients the day after surgery such as addressing patient questions and concerns as well as reviewing positioning and PO care instructions. However, PO day 1 visits can be logistically challenging, costly, and/or inconvenient for certain patients and families (eg, satellite office patients). Therefore, this study aims to determine the proportion of VR surgery patients with broad indications and procedures that developed complications or required changes in management at their first PO visit on day 3 or later. Short- and long-term outcomes were included to determine whether deferred follow-up led to poor surgical outcomes. Methods A retrospective, consecutive case series of a single VR surgeon (G.K.S) at a single tertiary referral center was conducted on 246 VR surgeries (231 patients) that had first PO examinations 1 The Retina Institute, St. Louis, MO, USA Corresponding Author: Gaurav K. Shah, MD, The Retina Institute, 1600 South Brentwood Blvd, Suite 800, St. Louis, MO 63144, USA. Email: gkshah1@gmail.com
Ho and Shah 127 Table 1. Patient Characteristics. Number of patients 231 Number of surgeries 246 Mean age, y (SD) 68 (13.0) Male, n (%) 109 (47.2) Female, n (%) 122 (52.8) Right eyes, n (%) 113 (45.9) Left eyes, n (%) 133 (54.1) Local anesthesia, n (%) 244 (99.2) General anesthesia, n (%) 2 (0.8) Preexisting glaucoma/ocular hypertension, n (%) 37 (15.0) Mean preoperative intraocular pressure (SD) 15.7 (5.5) Mean preoperative logmar visual acuity (SD) 1.09 (0.9) Preoperative lens status (%) Phakic 113 (45.9) Posterior chamber IOL 125 (50.8) Anterior chamber IOL 3 (1.2) Aphakic 5 (2.0) Abbreviations: IOL, intraocular lens; logmar, logarithm of the minimum angle of resolution. at day 3 or more from January, 1, 2008 to December 31, 2013 for logistical, personal, or geographic factors (eg, satellite office patients). Institutional review board (St. Luke s Hospital, St. Louis, Missouri) approval was obtained. Eyes with a variety of retinal conditions, procedures, and tamponade agents were analyzed at the first PO visit to identify which eyes developed and were associated with elevated IOPs (IOPs 30), hypotony (IOP 5), or need for early intervention (Fisher exact test, 2-tailed, statistically significant if P <.05). Of the 233 vitrectomy cases, pars plana vitrectomy (PPV) + scleral buckle, 228 (97.9%) cases utilized 23-gauge instrumentation and 5 (2.1%) utilized 20-gauge instrumentation. All patients were prepped with 5% povidine iodine solution. All trocars were inserted obliquely. When a gas tamponade or silicone oil (SO) was utilized, patients received a drop of topical brimonidine 0.2% or timolol 0.5% dorzolamide 2.0% at the end of the case. Data collected included patient s age, eye involved, preoperative diagnoses, preoperative examination findings, intraoperative details, and PO findings/complications. Examinations from PO weeks 1 to 4 and months 3 to 8 were reviewed to assess short- and long-term outcomes. All eyes with PO visits at day 1 or 2 were excluded. Eyes that did not have follow-up visits with our institution at weeks 1 to 4 and/or months 3 to 8 were excluded from the data analysis for these respective visits. Results In this 5-year span, 246 surgeries were performed on 231 patients with a mean age of 68 years. About 244 (99.2%) cases were done with retrobulbar anesthesia. Thirty-seven (15.0%) eyes had preexisting glaucoma or were on glaucoma drops. Lens status included 113 (45.9%) phakic eyes, 125 (50.8%) eyes with posterior chamber intraocular lenses, 3 (1.2%) with anterior chamber intraocular lenses, and 5 (2.0%) were aphakic(table1). Table 2. Types of Vitreoretinal Surgery Performed. Procedures n ¼ 246 PPV 218 (89%) Scleral buckle þ PPV 15 (6%) Scleral buckle 7 (3%) Suprachoroidal drug delivery 3 (1%) Open globe repair 2 (1%) Pneumatic retinopexy 1 (<1%) Abbreviation: PPV, pars plana vitrectomy. Table 3. Indications for Vitreoretinal Surgery. Surgical Indications n ¼ 246 Epiretinal membrane/vitreomacular traction 80 (33%) Complex retinal detachment 62 (25%) Vitreous hemorrhage 31 (13%) Macular hole 23 (9%) Retinal detachment 22 (9%) Retained lens fragments 9 (4%) Vitreous debris (vitritis, PVD, etc) 6 (2%) Submacular hemorrhage 6 (2%) Silicone oil tamponade 2 (1%) Trauma/open globe 2 (1%) Endophthalmitis 2 (1%) Dislocated IOL 1 (<1%) Abbreviations: IOL, intraocular lens; PVD, posterior vitreous detachment. Surgical indications and types of surgery performed are detailed in Tables 2 and 3. Of those with PPV, 23 (9.9%) eyes had all sclerotomies sutured, whereas the remaining 210 (90.1%) eyes were not sutured or had individual sclerotomies sutured if they were leaking at the end of surgery. Tamponade agents included air (n ¼ 170, 69.1%), sulfur hexafluoride (SF 6,n¼ 33, 13.4%), SO (n ¼ 17, 6.9%), and perfluoropropane (C 3 F 8,n¼ 16, 6.5%). Ten (4.1%) eyes did not receive a tamponade agent. On the first PO visit day 3 or more (mean 4.5 days, standard deviation [SD]: 3.7), notable findings included 8 (3.3%) eyes with hypotony (IOP 5), 8 (3.3%) elevated IOP (IOP 30, 3 of which had preoperative histories of glaucoma or antihypertensive drops use), 2 (0.8%) choroidal detachments, 1 (0.4%) vitreous hemorrhage, and no eyes with endophthalmitis. Only 5 (2.0%) of eyes required any immediate intervention, 4 eyes increased IOP medications and 1 eye decreased IOP medication (Table 4). Indication for surgery, type of surgery, and tamponade agent were not statistically significant or predictive of which eyes developed elevated IOP, hypotony, or required intervention at first PO visit (Fisher exact test, P >.05 for all). At the PO week 1 to 4 visit, 1 phthisical eye with a history of a open globe injury remained hypotonous while the other hypotonous eyes normalized. Nine eyes exhibited an IOP 30, all of which were new elevations in eyes that were normotensive at first PO visit with mean onset 22.6 (SD: 11.6) days. Of these 9 eyes, 5 had prior histories of glaucoma
128 Journal of VitreoRetinal Diseases 1(2) Table 4. First Postoperative Visit 3 Days Findings. Postoperative Findings and Diagnoses n ¼ 246 Mean days for first postoperative visit, (SD) 4.5 (3.7) Documented pain or discomfort 17 (6.9%) Mean intraocular pressure 14.2 (5.8%) Hypotony: IOP 5 8 (3.3%) IOP 30 8 (3.3%) Choroidal detachments a 2 (0.8%) Vitreous hemorrhage 1 (0.4%) Endophthalmitis 0 (0%) Intervention 5 (2.0%) IOP medications increased 4 (1.6%) IOP medications decreased or stopped 1 (0.4%) Abbreviation: IOP, intraocular pressure. a One patient had a severe coughing spell intraoperatively. The other patient was on warfarin. Table 5. Postoperative Visit Week 1 to 4 Findings. Postoperative Findings and Diagnoses n ¼ 218 Documented pain 7 (3.2%) Mean intraocular pressure (SD) 17.3 (5.8) Hypotony: IOP 5 a 1 (0.5%) IOP 30 9 (4.1%) Mean postoperative day with onset of IOP 30 (SD) 22.6 (11.6%) New IOP elevation 9 (4.1%) Continued IOP elevation from first PO visit 0 (0%) Vitreous hemorrhage 2 (0.9%) Endophthalmitis 0 (0%) Intervention 13 (6.0%) IOP medications increased b 10 (4.6%) IOP medications decreased or stopped 2 (0.9%) Macular hole reoperation 1 (0.5%) Abbreviations: IOP, intraocular pressure; PO, postoperative. a Phthisical eye after open globe repair. b IOP medications increased in eyes with IOP 25 to 30. or use of glaucoma drops. All 8 eyes with elevated IOP on first PO visit normalized with or without glaucoma drops. There were no cases of endophthalmitis. Thirteen (6.0%) of eyes required intervention at this visit 10 eyes (4.6%) had IOP medication increased, 2 (0.9%) decreased/stopped IOP medication, and 1 (0.5%) had a reoperation for a macular hole (Table 5). At PO months 3 to 8, 2 (0.9%) eyes were hypotonous, 6(2.7%) hadiop30 (4 of which had prior histories of glaucoma or use of glaucoma drops), 5 (2.2%) had vitreous hemorrhages, 3 (1.3%) had rhegmatogenous retinal detachments, 2 (0.9%) had ischemic optic neuropathies, and 1(0.4%) open globe repair became phthisical. Nine (4.0%) eyes required intervention, including 3 (1.3%) reoperations for retinal detachments (following an open globe repair, a membrane peel for myopic macular schisis, and a subretinal tissue plasminogen activator injection case for submacular hemorrhage from neovascular age-related macular degeneration), 1 (0.4%) reoperation for vitreous hemorrhage after prior PPV for Table 6. Postoperative Month 3 to 8 Findings. Postoperative Findings and Diagnoses n ¼ 225 Mean logmar visual acuity (SD) 0.75 (0.6) Mean intraocular pressure (SD) 16.0 (5.9) Hypotony: IOP 5 a 2 (0.9%) IOP 30 6 (2.7%) New IOP elevation 4 (1.8%) Continued IOP elevation 2 (0.9%) Vitreous hemorrhage 5 (2.2%) Rhegmatogenous retinal detachment 3 (1.3%) Ischemic optic neuropathy 2 (0.9%) Phthisis bulbi 1 (0.4%) Endophthalmitis 0 (0%) Intervention 9 (4.0%) IOP medications escalated 1 (0.4%) IOP medications decreased or stopped 2 (0.9%) Glaucoma procedure referral 2 (0.9%) Reoperation for RRD (%) 3 (1.3%) Reoperation for VH (%) 1 (0.4%) Abbreviations: IOP, intraocular pressure; logmar, logarithm of the minimum angle of resolution; RRD, rhegmatogenous retinal detachment; VH, vitreous hemorrhage. a Includes phthisical eye after open globe repair and a no light perception eye from end-stage proliferative diabetic retinopathy/ischemic optic neuropathy. proliferative diabetic retinopathy/tractional retinal detachment, and 5 (2.2%) adjustments in IOP management. Of the 6 (2.7%) eyes with IOP 30 (1 eye had glaucoma medications escalated, 2 were referred to a glaucoma specialist for possible procedure) (Table 6). Discussion Looking specifically at PO day 1 visits, an analysis by Alexander et al reported low intervention rates of 3.7% to 5% (273 total patients) after 20- or 23-gauge PPV + phacoemulsification: 10 eyes required changes in IOP medications and 4 returned to operating room (1 flat anterior chamber, 1 large hyphema, 1 retained anterior chamber lens fragment, and 1 retained intraocular cotton fiber). 13 Also, since smaller gauge surgery is becoming more popular, a report by the American Academy of Ophthalmology showed that advancements with small-gauge vitrectomy afford acceptably low incidence of adverse events which are comparable with those observed with conventional 20-gauge vitrectomy. 14 Therefore, despite the broad and sometimes complex indications/procedures performed in this study, deferring the first PO visit to day 3 or later (mean 4.5 days) can be a plausible option for certain patients such as those that travel from satellite offices or have logistical issues. It is difficult to say how low an intervention rate should be before the omission of PO visits 1 or 2 days after surgery will be considered a safe and sensible practice. Looking at cataract surgery which transitioned from extracapsular cataract extraction to phacoemulsification, one study suggests that if the intervention rate is less than 5%, the PO day 1 visit is probably unecessary. 5 Only 2.0% of the eyes in our study required
Ho and Shah 129 immediate intervention (in the form of IOP medication adjustments) on their first visit, but this rate could be lower if only more routine VR surgeries were included. Elevated IOP One major concern on the PO day 1 visit is elevated IOP, which was reported to occur in 6% and 67% of eyes following intravitreal gas injection with 20-gauge vitrectomy. 15-19 However, with smaller gauge surgery, several studies report a low incidence, 0% to 21% of elevated IOP in the early PO course. 13,19-22 Gosse et al conjecture that the sutureless transconjunctival incisions used for small-gauge vitrectomy can act as 1-way valves, allowing the release of a small amount of air or gas if the IOP increases significantly. This is similar to the release of bubbles from sclerotomies seen intraoperatively until the IOP approaches a more normal range. 22 As such, the omission of PO day 1 visits may be justified, particularly for those without a history of glaucoma. Prophylactic Perioperative Aqueous Suppressants Several studies utilized various regimens of prophylactic topical and/or oral aqueous suppressants to decrease the incidence of elevated IOP. Alexandar et al utilized a 7-day course of acetazolamide 250 mg slow-release twice daily and 1-month course of timolol 0.25% twice daily after 20- or 23-gauge vitrectomy. About 0.7% of these patients required unexpected intervention on day 1 owing to IOP >30 (2/273), but 1.5% (4/273) did have an IOP <6. 13 Other studies, similar to ours, used preoperative and/or intraoperative topical aqueous suppressants to decrease the incidence of elevated IOP particularly in the early PO period. Studies have shown that this period is most critical because the most rapid rate of volume increase occurs within 5 to 8 hours, and the maximum size of the longacting gas bubble is not reached until 24 to 48 hours for SF 6 and 72 to 96 hours for C 3 F 8. 23-26 Sciscio et al used apraclonidine 1% preoperatively at the completion macular hole surgery with small-gauge vitrectomy and 16% C 3 F 8. About 8.3% (1/12) of eyes had an IOP > 30 while their control group without topical drops exhibited a relatively higher incidence of elevated IOP (28.6%, 4/14) in the immediate PO period between 24 and 48 hours. 27 Meanwhile, Mittra et al showed that the use of a combination of 3 topical aqueous suppressants (0.5% timolol maleate, 0.5% apraclonidine hydrochloride, 2% dorzolamide hydrochloride, or 0.2% brimonidine tartrate) 5 to 10 minutes apart after 20- gauge PPV with long-acting gas tamponade was effective in reducing the incidence of significant IOP elevation after surgery. There was a reported incidences of IOP >30 in 5% (1/20) of treatment eyes versus 28.6% (6/21) of control eyes in the early PO period, and the control eyes had a mean 8 mm Hg increase in IOP during the critical 6-hour PO period. 28 In Benz et al, eyes treated with 0.5% timolol 2.0% dorzolamide immediately after 20-gauge PPV with long-acting gas tamponade had no difference between the IOP measured immediately postoperatively and at the 5-hour PO point. However, control eyes had a mean 12 mm Hg increase in IOP at the 5-hour PO point, and the IOP was still elevated at day 1. 29 In our study, we utilized a drop of topical 0.2% brimonidine or 0.5% timolol 2.0% dorzolamide at the end of surgeries with gas or SO tamponade. There was a 3.3% incidence of IOPs 30 at the first PO visit day 3 or later. Interestingly, 11 (4.5%) of eyes with elevated IOP 30 did not develop this until PO week 1 to 4 or later. This suggests that prophylactic aqueous suppressants can decrease the incidence of elevated IOP, and some eyes may exhibit new IOP elevations later in the PO course. Nonetheless, most pressure spikes occurred in patients with a history of glaucoma or ocular antihypertensive medication use so it may be safer to either see such patients sooner or prophylactically treat them with antihypertensive medications. Hypotony There is also a concern that unsutured sclerotomies may leak after surgery which can lead to a host of complications such as incomplete gas fills, hypotony, choroidal detachments, or endophthalmitis. Several reports have shown the prevalence of postsurgical hypotony using sutureless small-gauge surgery to be up to 20%. 30-39 However, other studies have exhibited similar rates of hypotony between small-gauge PPV and sutured 20-gauge PPV. 21,34,40-43 One prospective study using anterior segment optical coherence tomography showed that eyes undergoing 23-gauge PPV with oblique incisions exhibited apposition of the internal edges of sclerotomy wounds at PO day 1. 44 In another study of 25-gauge PPV, the incidence of hypotony on PO day 1 was significantly lower in eyes with oblique insertion (1.8%) than direct cannula insertion (10%). 45 In our study, 3.3% of eyes with oblique incisions were hypotonous at the first PO visit, 5 of which involved complex retinal detachments and 1 globe repair, but all IOPs normalized by PO weeks 1 to 4 except the open globe that became phthisical. Therefore, the use of sutureless smallgauge vitrectomy is now widely accepted and wound construction can help keep the rates of PO wound leaks and hypotony low. Endophthalmitis The incidence of acute PO endophthalmitis after small-gauge PPV has been reported to be higher than that observed after 20- gauge PPV with rates up to 0.84%. 46-50 However, additional studies did not show a statistically significant difference in incidence of endophthalmitis. 51-55 Over time, modifications in wound construction, surgical technique, surgical equipment/platforms, or a combination thereof have led to a reduction in the incidence of infection to levels similar to those reported after 20-gauge surgery. In addition, air or gas may assist in sealing unsutured sclerotomies. As such, no cases of endophthalmitis were encountered throughout the duration of this study.
130 Journal of VitreoRetinal Diseases 1(2) Study Limitations There are inherent limitations to this retrospective study. First, eyes with operations between January 1, 2008, and December 31, 2013 by 1 primary surgeon were included. Different results and conclusions may have been obtained if a different timeframe was analyzed. Also, the broad range of surgical indications/surgeries in this study may not represent the typical case load for other academic or nonacademic practices. In fact, rates of interventions and complications may have been lower if only more routine cases were included. Furthermore, the results of 1 surgeon with his/her surgical techniques/skill, cosurgery with VR fellows, and practice patterns like the use of prophylactic IOP medication use cannot be extrapolated to other VR surgeons with different practice patterns. Finally, patients in this study were often from satellite clinics and the follow-up visits after the first PO visit declined. These patients often were referred back to their referring physicians for long-term follow-up. Therefore, data on late complications after deferred PO care may not accurately represent this study population. Conclusion Postoperative day 1 visits do serve a number of roles including screening for early complications (such as corneal defects, intraocular lens displacement, PO pain/nausea, etc.), patient reassurance, PO care review, and immediate feedback on intended surgical outcomes. However, more advanced vitrectomy platforms, new VR instrumentation (valved cannulas), and small-gauge surgery (smaller incisions, self-sealing wounds, less surgical trauma, and less inflammation) have made VR surgery safer. 14,21,30-35,42,45,46,56,57-58 Despite the broad and sometimes complex indications/procedures performed in this study, only 2.0% of eyes required immediate intervention in the form of IOP medication adjustments on the first PO visit (day 3 or later), 6.0% of eyes required intervention at PO weeks 1 to 4, and 4.0% of eyes required intervention at PO months 3 to 8. Therefore, patients with logistical, personal, or geographic factors (eg, satellite office patients) and first PO visits 3 or more days after VR surgeries had low intervention rates in the immediate PO period and throughout the course of the study. Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Research is supported in part by the Retina Research Development Foundation (RRDF, St. Louis, Missouri) but this funding organization had no role in the design or conduct of this research. References 1. Isernhagen RD, Michels RG, Glaser BM, de Bustros S, Enger C. Hospitalization requirements after vitreoretinal surgery. Arch Ophthalmol. 1988;106(6):767-770. 2. Costen MT, Newsom RS, Wainwright AC, Luff AJ, Canning CR. Expanding role of local anesthesia in vitreoretinal surgery. Eye (Lond). 2005;19(7):755-761. 3. Newsom RSB, Wainwright AC, Canning CR. Local anaesthesia for 1221 vitreoretinal procedures. Br J Ophthalmol. 2001;85(2):225-227. 4. Fernando A, Gorman C. 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