Intravitreal triamcinolone for treatment of complicated proliferative diabetic retinopathy and proliferative vitreoretinopathy
Wuqaas M. Munir,* MD; Jose S. Pulido,*† MD, MS; Mithlesh C. Sharma,* MD; Bruce M. Buerk,* MD
ABSTRACT • RÉSUMÉ Background: We present a retrospective evaluation of the clinical outcome and complications associated with intravitreal injection of unaltered triamcinolone acetonide in conjunction with pars plana vitrectomy and silicone oil injection for the treatment of complicated proliferative diabetic retinopathy with tractional retinal detachment and severe proliferative vitreoretinopathy. Methods: Thirteen eyes of 12 consecutive patients were identified from a computerized patient database. All eyes were operated on by the same surgeon and received 4 mg of unaltered, commercially available triamcinolone acetonide intravitreally, before silicone oil injection. The patients were followed for a mean of 4.7 months (range 1−15 months), and demographic as well as pertinent preoperative and postoperative clinical information was gathered. Results: At the last follow-up visit, vision had improved in 4 eyes, remained stable in 5 eyes, and worsened in 4 eyes. The retina was attached at the end of follow-up in 10 of the 13 eyes. Eight of the 13 eyes did not show any clinical signs of reproliferation or redetachment during the course of follow-up. The mean intraocular pressure did not increase (preoperative value was 10.8 ± 6.22 mm Hg with a range of 0−22 mm Hg; at last follow-up, mean pressure was 9.6 ± 3.86 mm Hg with a cumulative postoperative range of 0−26 mm Hg). Steroid crystals were visible at 1 month postoperatively in 3 eyes and did not hinder fundus examination significantly. Interpretation: The intravitreal injection of low-dose, unaltered triamcinolone acetonide in the setting of pars plana vitrectomy and silicone oil injection for the treatment of proliferative vitreoretinopathy and complicated proliferative diabetic retinopathy appears to be well tolerated. Further controlled study is needed to clearly define the potential beneficial effects of intravitreal steroids in these 2 disease processes. Contexte : Nous présentons une étude rétrospective des résultats cliniques et des complications associées à l’injection intravitréenne d’acétonide de triamcinolone non modifié conjointement avec la vitrectomie par la pars plana et l’injection d’huile
From *the Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago Eye and Ear Infirmary, Chicago, Ill., and † the Mayo Clinic, Rochester, Minn. Presented in part at the Association for Research in Vision and Ophthalmology meeting in Fort Lauderdale Apr. 25–29, 2004 Originally received Jul. 8, 2004 Accepted for publication Apr. 11, 2005
Correspondence to: Dr. Jose S. Pulido, Mayo Clinic, 200 First St. SW, Rochester MN 55905; fax (507) 284-4612; pulido.jose@mayo.edu This article has been peer-reviewed. Can J Ophthalmol 2005;40:598–604
598
Intravitreal triamcinolone—Munir et al
Intravitreal triamcinolone—Munir et al
de silicone pour le traitement de la rétinopathie diabétique proliférante compliquée, avec décollement tractionel de la rétine et vitréorétinopathie proliférante sévère. Méthodes : Treize yeux de 12 patients consécutifs ont été repérés dans une base de données informatisée de patients. Ils ont tous été opérés par le même chirurgien et reçu dans le vitré 4 mg d’acétonide de triamcinolone non modifié et accessible sur le marché, avant l’injection d’huile de silicone. Les patients ont été suivis pendant 4,7 mois en moyenne (entre 1 et 15 mois) et l’on a colligé l’information démographique de même que clinique pertinente avant et après l’opération. Résultats : Lors de la dernière visite de suivi, la vision s’était améliorée dans 4 yeux, était demeurée stable dans 5 et avait empiré dans 4. À la fin du suivi, la rétine était attachée dans 10 des 13 yeux. Huit des 13 yeux ne montraient pas de signes de reprolifération ni de redécollement au cours du suivi. La moyenne de la pression intraoculaire n’avait pas augmenté (la valeur préopératoire était 10,8 ± 6,22 mm Hg avec écart de 0 à 22 mm Hg; au dernier suivi, la pression moyenne était 9,6 ± 3,86 mm Hg avec un écart cumulatif postopératoire de 0 à 26 mm Hg). Les cristaux de stéroïde étaient visibles 1 mois après l’opération dans 3 yeux, mais n’ont pas gêné l’examen du fond d’œil de façon significative. Interprétation : L’injection intravitréenne d’une faible dose d’acétonide de triamcinolone non modifié en conjunction avec la vitrectomie par la pars plana et l’injection d’huile de silicone pour le traitement de la vitréorétinopathie proliférante et la rétinopathie diabétique proliférante compliquée semblent bien tolérées. D’autres essais comparatifs seront nécessaires pour définir clairement les bienfaits potentiels des stéroïdes intravitréens pour le traitement de ces 2 maladies.
P
roliferative vitreoretinopathy (PVR) is one of the most important causes of failure of retinal reattachment.1 Advances in vitreoretinal surgical techniques, including an increased use of silicone oil for postsurgical tamponade—particularly in eyes with complex rhegmatogenous retinal detachment (RRD) with advanced PVR or proliferative diabetic retinopathy (PDR) with tractional retinal detachment (TRD)—has led to improved function and visual outcomes.1,2 Perisilicone oil proliferation of fibroglial membranes, however, may compromise surgical success and remains a concern.3 Consequently, the last decade has witnessed extensive study of proliferative disease states such as PVR and PDR, and a variety of treatment methods, including the perioperative use of heparin and 5-fluorouracil in irrigating fluids during pars plana vitrectomy (PPV), have been tried in an attempt to reduce the incidence of PVR in high-risk proliferative states, but with only limited success.4 Oral, topical, and periocular steroids have been widely used in the past in many pathologic ocular conditions that have an underlying inflammatory basis. Both the retinal neovascular proliferation in
PDR and the fibroblastic proliferation of PVR often have an accompanying inflammatory component. Machemer and other researchers showed that intravitreal steroid injections, particularly triamcinolone acetonide, were not toxic to the eye5,6 and may potentially be important in quelling intraocular inflammation and vitreoretinopathy caused by fibroblastic proliferation.7–9 It is therefore intuitive that intravitreal steroid injections could be beneficial both in PDR with TRD and in PVR. We report a retrospective evaluation of the results obtained with eyes that received commercially available intravitreal triamcinolone acetonide (Kenalog, Bristol-Myers Squibb Company, Princeton, N.J.) in conjunction with PPV and silicone oil injection as an adjunctive treatment for complicated PDR and PVR. The outcomes and complications of intravitreal steroid injection in this clinical setting are described.
METHODS
We identified all consecutive eyes of patients over the age of 18 in a computer-generated patient database who had undergone PPV with silicone oil injection for the treatment of complicated PDR or RRD
CAN J OPHTHALMOL—VOL. 40, NO. 5, 2005
599
Intravitreal triamcinolone—Munir et al
Table 1—Patient details for complicated proliferative diabetic retinopathy
Age Sex Eye Diagnosis Previous vitreoretinal surgery Yes No Yes Yes No Yes Followup, mo 11 4 3 2 1.5 1 Attached last visit Yes Yes Yes Yes Yes Yes Vision preop LP LP HM LP 20/70 LP Vision last visit NLP CF 1' HM HM HM LP IOP preop 15 11 13 14 0 12 IOP last visit 10 14 18 10 14 8
63 60 59 58 29* 29*
F F M M F F
OD OD OS OS OS OD
TRD Vitreous hemorrhage, TRD Bullous central TRD Total retinal detachment with PDR and PVR Severe TRD Vitreous hemorrhage with TRD and PVR
Note: mo = month; preop = preoperative; IOP = intraocular pressure; F = female; M = male; OD = right eye; OS = left eye; TRD = tractional retinal detachment; LP = light perception; NLP = no light perception; CF = counting fingers; HM = hand movements; PDR = proliferative diabetic retinopathy; PVR = proliferative vitreoretinopathy. *Same patient.
with PVR. All eyes meeting these eligibility criteria had received a 0.1-mL intravitreal injection containing 4 mg of commercially available triamcinolone acetonide. No identified eyes were excluded from the study. Data were collected for each patient at the preoperative visit and at 1 day, 1 week, 1 month, and last follow-up visit postoperatively. A total of 13 eyes (8 right eyes, 5 left eyes) were identified, of 12 patients (5 males, 7 females). The mean age was 52.3 years (range of 22–72 years) and the mean follow-up time was 4.7 months (range of 1–15 months). All operations were performed by a single surgeon (J.S.P.) using the same surgical techniques. A standard 3-port PPV was performed for all patients, with removal of the vitreous to the vitreous base and peeling of preretinal membranes. Temporary keratoprosthesis, intraoperative perfluorocarbon liquids, endolaser, removal of prior silicone oil, and surgical peripheral iridectomy were performed as dictated by each case. An unaltered, commercially available 0.1-mL solution containing 4 mg of triamcinolone acetonide was injected into all eyes through an open sclerotomy towards the 6 o’clock position, before injecting 5000-centistoke silicone oil. Subconjunctival injections of antibiotics and dexamethasone were also given in all eyes.
RESULTS
Six eyes from 5 patients had a preoperative diagnosis of complicated PDR with TRD (Table 1). The mean age was 49.7 years (range of 29–63 years) and the mean follow-up in this group was 3.8 months (range of 1–11 months). All 5 patients had diabetes mellitus as well as coexisting hypertension. All 6 eyes had TRD involving or threatening the central macula and all eyes had received prior laser panretinal photocoagulation. Four of 6 eyes had undergone prior vitreoretinal surgery, and all 4 had undergone more than 1 such operation. Three of 6 eyes had previous silicone oil injection, 1 eye had previous gas injection, and 1 eye had previous cryotherapy; none had previous surgery for scleral buckling. Three eyes were aphakic prior to this intervention, 1 eye had cataract, and 2 eyes had clear lenses. The remaining 7 eyes with RRD with PVR were from 7 patients (Table 2). The mean age of this group was 54.6 years (range of 22–72 years) and the mean follow-up time was 5.6 months (range of 1–15 months). All 7 eyes had PVR grade C or D. Four of the 7 eyes had undergone prior vitreoretinal surgery, and all 4 had undergone more than 1 such operation. Three eyes had previous silicone oil injection, 1 eye
600
CAN J OPHTHALMOL—VOL. 40, NO. 5, 2005
Intravitreal triamcinolone—Munir et al
Table 2—Patient details for rhegmatogenous retinal detachment with proliferative vitreoretinopathy
Age Sex Eye Diagnosis FollowPrevious vitreoretinal up, mo surgery No Yes Yes Yes No No 3 2 6 1 4 8 Attached last visit Yes Yes No Yes Yes No Vision preop CF 1' LP HM HM 20/40 LP Vision last visit 20/200 HM HM HM CF 4" LP IOP IOP preop last visit 17 8 0 6 12 10 8 7 10 10 6 4
30 69 72 71 22 71
M M M F F F
OS OD OS OD OD OD
RRD with PVR RRD with PVR RRD with PVR and TRD Total RRD with anterior and subretinal PVR RRD with PVR and TRD Giant RRD with PVR and suprachoroidal hemorrhage RRD with PVR and subretinal bands
47
F
OD
Yes
15
No
HM
LP
22
6
Note: mo = month; preop = preoperative; IOP = intraocular pressure; M = male; F = female; OD = right eye; OS = left eye; RRD = rhegmatogenous retinal detachment; PVR = proliferative vitreoretinopathy; TRD = tractional retinal detachment; CF = counting fingers; LP = light perception; HM = hand movements.
had previous gas injection, and 3 eyes had surgery for scleral buckling. Four eyes were aphakic prior to this intervention, 1 eye had cataract, 1 eye had a clear lens, and 1 eye was pseudophakic. Preoperative vision ranged from 20/40 to light perception (LP), and at last follow-up, postoperative vision ranged from 20/200 to no light perception (NLP). At last follow-up, vision had improved up to 2 lines in 4 eyes (2 with PDR and 2 with PVR), had worsened in 4 eyes (2 with PDR and 2 with PVR), and was stable in the remaining 5 eyes (2 with PDR and 3 with PVR) (Fig. 1). In the 4 eyes that lost vision, all were at their final visual acuity by postoperative day 1. Only 2 eyes lost more than 2 lines of vision: one with PVR requiring lensectomy, multiple breaks threatening the macula, and a postoperative hyphema; and the other with PDR and severe TRD, active neovascularization, and marked fibrosis in the posterior pole. The average preoperative intraocular pressure (IOP) was 10.8 ± 6.22 mm Hg (range 0–22). The average first-day postoperative IOP was 18.3 ± 7.91 mm Hg (range 0–26), first-week average was 16.2 ± 5.65 mm Hg (range 9–26), and follow-up average was 9.6 ± 3.86 mm Hg (range 4–18) (Fig. 2). Flare and cell were assessed using a modified 0-to-4 slit-
lamp grading scale as described by Kraff and associates.10 On the first postoperative day, both flare and cell were less than 3 for all eyes. By 1 week, no eye had a grading greater than 2, and by 1 month, no eye had a grading greater than 0.5, for either flare or cell. On the first postoperative day, the pain score, based on a 0-to-10 visual analog scale, was no greater than 5 for all eyes, and by 1 week, no eye had a grading greater than 3. Of the 5 eyes that were phakic prior to surgery, 2 eyes had lensectomy as part of the initial procedure. Of the remaining 3, 1 eye with a preoperative clear lens developed 3+ posterior subcapsular cataract; the second eye with a preoperative clear lens developed 1+ nuclear sclerosis and 1+ posterior subcapsular cataract; and the third eye had increased cataract changing from an initial 1–2+ nuclear sclerosis and 1–2+ posterior subcapsular cataract to a final 2+ nuclear sclerosis, 2+ posterior subcapsular cataract, and 1+ anterior cortical cataract. Two of the 6 eyes with PDR required reoperation before last follow-up because of reproliferation and redetachment; at the time of last follow-up, however, the retinas in all 6 eyes remained attached. Notably, the 2 eyes that required reoperation were from the same patient with complex PDR. Three of the 7 eyes
CAN J OPHTHALMOL—VOL. 40, NO. 5, 2005
601
Intravitreal triamcinolone—Munir et al
Visual acuity, preoperative
Fig. 1—Scatter graph of preoperative visual acuity versus vision at last postoperative follow-up for 13 eyes injected with intravitreal triamcinolone in conjunction with pars plana vitrectomy and silicone oil injection. Points below the line represent patients whose vision improved; points above, patients whose vision worsened postoperatively. The 2 points on the line represent the results for 5 eyes, while the point LP-to-HM (below the line) represents the results of 2 eyes, giving n = 13 (see Tables 1 & 2). (CF = counting fingers; HM = hand movements; LP = light perception; NLP = no light perception).
with PVR also reproliferated with redetachment, which was clinically first evident at 1 month, 1 month, and 9 months. Two of the eyes had redetachment surgery, but all 3 remained detached at last follow-up. Of note, 1 eye was hypotonous preoperatively and had a concurrent penetrating keratoplasty with subsequent extended hypotonia and graft failure; the second had persistent vitreous hemorrhage requiring reoperation and also with corneal graft failure; and the third had a large open funnel and persistent hyphema postoperatively. Triamcinolone acetonide crystals were visible over the retina at 1 month in only 1 PDR eye and 2 PVR eyes, with no crystals lying on the macula. By last follow-up at 2, 3, and 8 months, the crystals were no longer detectable by examination. No patient had any clinically detectable triamcinolone crystals in the anterior chamber.
INTERPRETATION
Visual acuity, last postoperative follow-up
IOP, preoperative, mm Hg
Fig. 2—Scatter graph of preoperative intraocular pressure (IOP) versus IOP at last postoperative follow-up for 13 eyes injected with intravitreal triamcinolone in conjunction with pars plana vitrectomy and silicone oil injection. Points below the line represent patients whose IOP decreased after surgery; points above, patients with increased postoperative IOP.
Since the introduction of intravitreal steroid use, this modality of treatment has been recommended for a wide range of ocular disease states, including diabetic macular edema11 and-age related macular degeneration.12,13 The role of intravitreal steroid injections in the setting of RRD with PVR and PDR, however, has not been clearly delineated. Jonas showed that concentrated intravitreal triamcinolone acetonide was safe and potentially beneficial in both PVR and PDR following PPV.14,15 Of note, Jonas and associates used 0.2 mL of concentrated solution containing 10 to 20 mg triamcinolone acetonide with a minimally diluted vehicle in an effort to reduce the potential for vehicle-induced inflammatory response.14,15 In these studies, 17 of 29 eyes with PDR, and all eyes with PVR, had silicone oil injected prior to the steroid injection. This work demonstrated the safety of intravitreal steroids when combined with the prolonged presence of silicone oil.14–16 Concern has been raised regarding cataract formation and increased IOP following the intravitreal injection of steroids.17,18 As many as 30% of patients receiving intravitreal injection of triamcinolone acetonide may experience a rise in IOP greater than 5 mm Hg over the first 3 months.19 Most cases of increased IOP are temporary, and usually resolve by 6 months.18 Rarely, intractable glaucoma requiring filtering surgery may occur following the intravitreal injection of high-dose triamcinolone acetonide.18,20 We used a considerably smaller dose than Jonas
602
IOP, last postoperative follow-up, mm Hg
CAN J OPHTHALMOL—VOL. 40, NO. 5, 2005
Intravitreal triamcinolone—Munir et al
did14,15 and, in fact, we did not experience persistent IOP elevation in any of our patients. Of note, none of the patients had a documented history of steroid “response” previously. Given the relatively high number of aphakic and pseudophakic eyes in the study, it is difficult to conclude what role the steroids played in advancing cataract formation over and above vitrectomy itself in the few phakic eyes we studied. The visual and structural outcomes in this study were confounded by the severity of disease encountered in this patient population. In none of the patients was vision loss progressive, which suggests acute surgical changes as the etiology, rather than chronic exposure to steroid. Comparisons to prior reports concerning structure are difficult to make, given the small sample size of our study. Still, the rate of retinal attachment in our PDR group (100%) was comparable to both Jonas’ reports (89.7% and 81.2%),15,16 while the rate of retinal attachment in our PVR group (57.1%) was less than that of the Jonas PVR treatment group (81.2%).14 The rate of attachment in our PVR group was similar to that of the Silicone Study.21 Again, the structural results and reoperation rate were likely affected by the more aggressive disease processes in this cohort. Some have questioned the excipients of commercially available steroid preparations, and previous data do suggest that certain steroid vehicles actually promote an inflammatory response.22 The vehicles of triamcinolone acetonide (Kenalog) and triamcinolone diacetate (Aristocort), however, did not show toxicity at concentrations as high as twice the standard concentration.22 Based on this work, commercially available triamcinolone acetonide was used in the present study without removal of the vehicle base. We found no appreciable increase in inflammation during the postoperative period. No steroid particles were detected in the anterior chamber as reported by Jonas.14,15 Others have been wary of the tendency of steroids such as triamcinolone acetonide to precipitate into white clumps in the vitreous and on the surface of the macula.14,15 Interestingly, Peyman and others have shown that the initial clouding of the vitreous following intravitreal injection can be beneficial in delineating the posterior hyaloid during vitrectomy.23,24 Even with the presence of intravitreal triamcinolone acetonide, the postoperative examination of the fundi of our patients was not significantly compromised (Fig. 3).
Fig. 3—Fundus photograph 2 months after intravitreal injection of triamcinolone acetonide as an adjunct to pars plana vitrectomy (PPV) and silicone oil injection for treatment of complicated proliferative diabetic retinopathy (PDR), with preservation of an adequate view to fundus detail.
Finally, considering the predicted increase in the half-life of steroids within a silicone oil medium, the role of intravitreal steroid injections in eyes filled with silicone oil has been examined. Studies have indeed shown an increased time period during which steroid levels are detectable in the vitreous when injected into silicone oil.25,26 Thus far, however, no associated retinal toxicity has been reported.26 In our study, no clinically detectable steroid crystals were present in the vitreous past 8 months. Although this initial study provided for consistent surgical technique of one primary surgeon, there were other limitations encountered. First, the number of patients in the study was limited. Because of the retrospective nature of this study, no control group of patients was available for comparison of efficacy. Neither the extremes of disease severity nor the level of previous surgical intervention could be stratified. Finally, in a prospective analysis with appropriate instrumentation it would have been possible to carry out more detailed and systematic clinical assessments. Still, this preliminary study suggests that, as a treatment for complicated PDR and PVR, unaltered, commercially available triamcinolone acetonide used as an intravitreal adjunct to PPV in silicone oil-filled eyes has few complications and warrants further investigation as a potential agent to quell postoperative inflammation and proliferation. We are also investi-
CAN J OPHTHALMOL—VOL. 40, NO. 5, 2005
603
Intravitreal triamcinolone—Munir et al
gating the use of other antiproliferative agents in silicone oil-filled eyes to identify those with no toxicity that may provide superior results to triamcinolone acetonide.
Supported in part by an unrestricted grant from Research to Prevent Blindness, Inc., New York, and an NIH Core Grant #EY 01792. The authors have no proprietary interest in any aspect of this study.
14.
15.
16.
REFERENCES
1. Sharma T, Gopal L, Shanmugam MP, et al. Management of recurrent retinal detachment in silicone oil-filled eyes. Retina 2002;22:153–7. Castellarin A, Grigorian R, Bhagat N, et al. Vitrectomy with silicone oil infusion in severe diabetic retinopathy. Br J Ophthalmol 2003;87:318–21. Lewis H, Burke JM, Abrams GW, et al. Perisilicone proliferation after vitrectomy for proliferative vitreoretinopathy. Ophthalmology 1988;95:583–91. Asaria RH, Kon CH, Bunce C, et al. Adjuvant 5-fluorouracil and heparin prevents proliferative vitreoretinopathy: Results from a randomized, double-blind, controlled clinical trial. Ophthalmology 2001;108:1179–83. McCuen BW II, Bessler M, Tano Y, et al. The lack of toxicity of intravitreally administered triamcinolone acetonide. Am J Ophthalmol 1981;91:785–8. Schindler RH, Chandler DB, Thresher R, et al. The clearance of intravitreal triamcinolone acetonide. Am J Ophthalmol 1982;93:415–7. Machemer R, Sugita G, Tano Y. Treatment of intraocular proliferations with intravitreal steroids. Trans Am Ophthalmol Soc 1979;77:171–80. Tano Y, Sugita G, Abrams G, et al. Inhibition of intraocular proliferation with intravitreal corticosteroid. Am J Ophthalmol 1980;89:131–6. Tano Y, Chandler D, Machemer R. Treatment of intraocular proliferation with intravitreal injection of triamcinolone acetonide. Am J Ophthalmol 1980;90:810–6. Kraff MC, Martin RG, Neumann AC, Weinstein AJ. Efficacy of diclofenac sodium ophthalmic solution versus placebo in reducing inflammation following cataract extraction and posterior chamber lens implantation. J Cat Refract Surg 1994;20: 138–44. Jonas JB, Kreissig I, Sofker A, et al. Intravitreal injection of triamcinolone for diffuse diabetic macular edema. Arch Ophthalmol 2003;121:57–61. Challa JK, Gillies MC, Penfold PL, et al. Exudative macular degeneration and intravitreal triamcinolone: 18 month follow up. Aust N Z J Ophthalmol 1998;26:277–81. Danis RP, Ciulla TA, Pratt LM, et al. Intravitreal triamci17.
2.
18.
3.
19.
4.
20.
21.
5.
6.
22.
7.
23.
8.
24.
9.
10.
25.
26.
11.
nolone acetonide in exudative age-related macular degeneration. Retina 2000;20:244–50. Jonas JB, Hayler JK, Panda-Jonas S. Intravitreal injection of crystalline cortisone as adjunctive treatment of proliferative vitreoretinopathy. Br J Ophthalmol 2000;84:1064–7. Jonas JB, Hayler JK, Sofker A, et al. Intravitreal injection of crystalline cortisone as adjunctive treatment of proliferative diabetic retinopathy. Am J Ophthalmol 2001;131:468–71. Jonas JB, Sofker A, Degenring R. Intravitreal triamcinolone acetonide as an additional tool in pars plana vitrectomy for proliferative diabetic retinopathy. Eur J Ophthalmol 2003;13: 468–73. Young S, Larkin G, Branley M, et al. Safety and efficacy of intravitreal triamcinolone for cystoid macular oedema in uveitis. Clin Experiment Ophthalmol 2001;29:2–6. Jonas JB, Kreissig I, Degenering R. Intraocular pressure after intravitreal injection of triamcinolone acetonide. Br J Ophthalmol 2003;87:24–7. Wingate RJ, Beaumont PE. Intravitreal triamcinolone and elevated intraocular pressure. Aust N Z J Ophthalmol 1999; 27:431–2. Jonas JB, Kreissig I, Degenring R. Secondary chronic openangle glaucoma after intravitreal triamcinolone acetonide. Arch Ophthalmol 2003;121:729–30. Abrams GW, Azen SP, McCuen BW, et al. Vitrectomy with silicone oil or long-acting gas in eyes with severe proliferative vitreoretinopathy: results of additional and long-term followup: Silicone Study Report 11. Arch Ophthalmol 1997;115: 335–44. Hida T, Chandler D, Arena JE, et al. Experimental and clinical observations of the intraocular toxicity of commercial corticosteroid preparations. Am J Ophthalmol 1986;101:190–5. Peyman GA, Cheema R, Conway MD, et al. Triamcinolone acetonide as an aid to visualization of the vitreous and the posterior hyaloid during pars plana vitrectomy. Retina 2000; 20:554–5. Sakamoto T, Miyazaki M, Hisatomi T, et al. Triamcinoloneassisted pars plana vitrectomy improves the surgical procedures and decreases the postoperative blood–ocular barrier breakdown. Graefes Arch Clin Exl Ophthalmol 2002;240: 423–9. Jonas JB. Concentration of intravitreally injected triamcinolone acetonide in intraocular silicone oil. Br J Ophthalmol 2002;86:1450–1. Kivilcim M, Peyman GA, El-Dessouky E, et al. Retinal toxicity of triamcinolone acetonide in silicone-filled eyes. Ophthalmic Surg Lasers 2000;31:474–8.
12.
Key words: intravitreal steroids, pars plana vitrectomy, proliferative diabetic retinopathy, proliferative vitreoretinopathy, triamcinolone acetonide
13.
604
CAN J OPHTHALMOL—VOL. 40, NO. 5, 2005