ORIGINAL STUDY
Risk Factors for a Severe Bleb Leak Following Trabeculectomy: A Retrospective Case-Control Study Chmielewska Karolina, MD, Catherine Baril, MD, Dominique Bourret-Massicotte, MD, Jean-Louis Anctil, MD, Louis Caron, MD, Annie Goyette, MD, and Be´atrice Des Marchais, MD, MSc
Purpose: To describe the population at risk of having a severe bleb leak needing a surgical repair in the operating room and to study risk factors associated with severe bleb leak. Patients and Methods: In this case-control study, 17 cases were enrolled and paired with 51 controls. We studied all patients having a surgical revision in our center for a severe bleb leak between January 1 and December 31, 2008. Three controls were paired to each case based on their surgery date. We then analyzed risk factors related to the patient, the intervention, and the postoperative follow-up. Results: Younger age was the only statistically significant risk factor for a severe bleb leak in our study. The odds of a severe bleb leak decreased as the age increased (P = 0.0029). In comparing the risk for a severe bleb leak in younger (below 55 y) versus patients aged 75 years or older, the odds ratio was 21.0. There were no statistically significant differences between cases and controls with respect to: type of glaucoma, number or types of previous ocular surgeries, number of preoperative topical medications, localization of the leak, localization of the wound (fornix or limbus-based), or the intraocular pressure on day 1 postoperative. Conclusions: Younger age at the time of trabeculectomy may be a risk factor for severe bleb leak. A trend was observed in which the patients under the age of 55 years were at greater risk for a severe bleb leak. Key Words: ophthalmology, glaucoma, filtering surgery, trabeculectomy
(J Glaucoma 2015;24:493–497)
D
espite the emergence of new surgical techniques for the treatment of glaucoma, trabeculectomy has remained the gold standard since the late 1960s. The procedure has evolved since then, especially with the introduction of antimetabolites. The use of antimetabolite agents such as mitomycin-C (MMC) and 5-fluorouracil (5-FU) in glaucoma filtering surgeries has greatly improved outcomes and is now Received for publication July 30, 2013; accepted August 11, 2014. From the Centre universitaire d’ophtalmologie et CUO-Recherche, Centre de recherche du CHU de Que´bec, Hoˆpital du Saint-Sacrement; De´partement d’ophtalmologie, Faculte´ de me´decine, Universite´ Laval, QC, Canada. Poster presentation of the study at ARVO Annual Meeting Association for Research in Vision and Ophthalmology, Fort Lauderdale, FL, May 7, 2012. Research projects in ophthalmology grant program from Pfizer was received for the conduct of this study. Pfizer was not involved in the study protocol nor publication decision. Disclosure: The authors declare no conflict of interest. Reprints: Be´atrice Des Marchais, MD, MSc, Centre universitaire d’ophtalmologie, Hoˆpital du St-Sacrement, 1050 ch. Sainte-Foy, QC G1S 4L8, Canada (e-mail: [email protected]). Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/IJG.0000000000000125
J Glaucoma
Volume 24, Number 7, September 2015
common practice in most Canadian centers. However, it is known that these agents increase the risks of hypotony, late bleb leaks, and endophtalmitis.1–4 Bleb leaks may occur early in the days following the surgery or even years later. The rate of these bleb leaks varies greatly between reports and is dependent on the length of the follow-up interval. Studies suggested that the rate of early bleb leak, occurring within 1 month of the surgery, is between 6% and 59%.5–9 Studies suggested that the reported incidence of late bleb leaks ranged from 2.9% to 24.6%, during a mean follow-up period of 36.5 months.1,10–12 With the use of antimetabolites, patients are now more carefully examined for leaks. Other than the use of antimetabolites, there is very little information about risk factors for bleb leaks. One review study identified the following risk factors for early bleb leak: Inferior location of conjunctival incision, One-layer closure, A history of ocular inflammatory disease, and, Older age at the time of surgery.5 Surgical approach also differentiated risk. A limbusbased procedure in contrast to a fornix-based procedure is a risk factor for leaks.8,13 Recently, Solus et al13 found limbus-based procedures were complicated by late bleb leaks, that is, significantly later than fornix-based procedures. In addition to the actual risk factors associated with surgery, postoperative manipulations in the office may also increase the risk of bleb leak. Surgeons often do suture lysis, needlings, or subconjunctival injections of antimetabolites to help reduce intraocular pressure or reduce the local inflammation. Each of these maneuvers may weaken the conjunctiva and hence increase the rate of bleb leaks. The impact of postoperative manipulations has not been extensively studied. One study showed no increase in bleb leaks within 1 month of the surgery,1 but little is known about late leaks associated with these postoperative manipulations. At our center, most leaks do not require repair in the operating room and can be managed in the office. Only persistent and severe leaks require repair in the operating room. The overall annual incidence of severe bleb leaks in our center is about 8.5%. This retrospective study was designed to describe the population at risk of having a severe bleb leak following a trabeculectomy, even years after initial surgery. We defined a severe bleb leak as a bleb leak requiring surgical repair in the operating room, because of few patients having severe bleb leaks in our center, we explored both early and severe bleb leaks.
PATIENTS AND METHODS A retrospective case-control study was conducted on patients who had undergone a surgical revision for a bleb www.glaucomajournal.com |
Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
493
Karolina et al
J Glaucoma
leak at our center between January 1 and December 31, 2008. Three controls were assigned for each case to increase the statistical power to detect a difference. As the number of cases is small, we acknowledge that this study is mainly descriptive and exploratory. The case group was composed of all the patients operated on at our center who had undergone a surgical revision for a severe bleb leak in our center between January 1 and December 31, 2008. Some of the main characteristics of the case group are presented in the Table 1. Only 1 patient was excluded from our study as the follow-up period was shorter than 2 months. The control group was composed of patients who had undergone a trabeculectomy by 1 of the 5 surgeons at our center but who did not have a bleb leak requiring surgical revision in the operating room. Each case was paired to 3 controls. All patients were operated on by 1 of the 5 glaucoma surgeons in our service. Controls were assigned to cases on the basis of the date of their surgery. Often, controls were operated on the same day but according to the statistician, a delay of up to 2 months between the surgery dates for cases and controls was acceptable to match controls to cases adequately. Only 1 control had a delay of >1 month between the surgery dates; all other controls were operated within 2 weeks of the corresponding case’s surgical date. When >3 controls were found for 1 case, 3 matching controls were randomly pooled and assigned to that one case. Our selection of controls as described above was a way to decrease bias in the technique, surgeon, assisting team, as well as materials and products used during any 1 trabeculectomy. Trabeculectomies were done to treat chronic open angle glaucoma, chronic angle closure glaucoma, mixed glaucoma, pigmentary dispersion glaucoma, normal tension glaucoma, pseudoexfoliation glaucoma, juvenile glaucoma, secondary glaucoma, increased episcleral venous pressure, and ocular hypertension (1 case of very high pressure uncontrolled by medical treatment). The surgical technique varies slightly from one surgeon to the other but generally included a fornix based flap, a squared scleral flap, an ostium with a punch, and closure with nylon 10-0 sutures. In this study, MMC was the only antimetabolite employed during trabeculectomy and it was used in all of our patients. Its concentration varied according to the route of delivery, that is, 0.1 mg/mL when injected subconjunctivally and 0.2 mg/mL when used on sponges applied to the sclera. The application duration of the sponges to the surgical site varied from 30 seconds to 3.5 minutes. Thirteen patients received a subconjunctival injection intraoperatively only (without adding MMC sponges’ applications); 5 patients were in the case cohort and 8 patients were in the control cohort. A patient was excluded from our study if the follow-up period was 1 month postoperatively, which differs from our current study in which late bleb leaks were included. As mentioned earlier, 6 patients suffered from a severe bleb leak 4 weeks or more after the surgery, and 2 of theses had a leak appear at 52 weeks or later postoperatively. The mean age in these patients was 62 years, no different than in the rest of the cases. The number of severe bleb leaks was too small to conclude that sex, surgical technique, and the type of glaucoma were risks factors. However, the case group had a tendency to have more patients with a fornix-based wound and a lesser proportion of women, although this was not statistically significant. In our study, the number of preoperative topical medications did not show an increased number of leaks. However, we did not have the information regarding the duration of topical treatment in our patients. It is now known that long-term treatment with topical agents may alter the conjunctiva, and hence increase complications such as leaks.14 We did not, however, look into this variable in this study. The present study found no significant risk associated with postoperative manipulations that contributed to the incidence of leaks. However, because of the exploratory nature of the current study, no conclusions can be reached regarding these risk factors. The patients with a late leak did not appear to be subject to more manipulations (needlings) that could have adversely affected the conjunctiva. Further, it is interesting to see that as the number of surgical repairs at the slit-lamp did not increase the odds of having a severe bleb leak, we therefore cannot yet define precise factors that should guide us to do an extensive repair in the operating room early after we find the leak. It is already known that for cystic avascular blebs that would result in a late leak, simple suturing does not usually resolve the problem. In our study 5 patients did not receive sutures in the clinic. A few patients had an avascular bleb that caused the surgeons to fear that simple suturing would fail to fix the leak, and possibly increase it due to its fragility.
Although the present study failed to show a significant difference between simple and combined surgery, one could suggest that there was a tendency to have more bleb leaks when cataract extraction was combined with trabeculectomy. One study shows that trabeculectomy alone seemed to have a higher risk of bleb leak than when combined with a cataract extraction.1 Our sample size may be too small to draw inferences or conclusions. We also looked at the number of patients who achieved an intraocular pressure below 15 mm Hg without any medications in each group and also found no statistically significant difference. However, this study was not powered to analyze the success of trabeculectomy in patients having a severe bleb leak leading to surgical revision in the operating room. Finally, all patients in the present study were operated on at the same center. This was very helpful in collecting data and diminishing confounding variables such as differences in the surgical support staff or differences in materials used. All of our glaucoma surgeons used a very similar method and similar values regarding concentration and the duration time of MMC administration (and no patients received 5-FU). As mentioned earlier, three controls were paired to one case on the basis of the surgical date to enable us to detect small differences if they existed. The results of this study suggest that younger age at the time of trabeculectomy (below 55 y of age) may be a risk factor for severe bleb leak. A trend was observed in which the younger the age of the patient, the greater the risk of the bleb leak. Our study included early and late bleb leaks; risk factors for each of these two categories might be different. As this study is mainly descriptive and exploratory, other larger prospective series will be needed to help define the specific risk factors in younger patients that may predispose them to early or late bleb leak leading to surgical repair in the operating room.
ACKNOWLEDGMENTS The authors thank Mrs Nathalie Laflamme, PhD, and Mr Paul-Marie Bernard for theirs statistical assistance and Mrs Marcelle Giasson for research coordinator assistance.
496 | www.glaucomajournal.com Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved. Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
J Glaucoma
Volume 24, Number 7, September 2015
Severe Bleb Leak Following Trabeculectomy
REFERENCES 1. Greenfield DS, Liebmann JM, Jee J, et al. Late-onset bleb leaks after glaucoma filtering surgery. Arch Ophthalmol. 1998; 116:443–447. 2. Wilkins M, Indar A, Wormald R. Intra-operative mitomycin C for glaucoma surgery. Cochrane Database Syst Rev. 2005;19: CD002897. 3. The Fluorouracil Filtering Surgery Group. Five-year follow-up of the Fluorouracil Filtering Surgery Study. Am J Ophthalmol. 1996;121:349–366. 4. Beckers HJ, Kinders KC, Webers CA. Five-year results of trabeculectomy with mitomycin C. Graefes Arch Clin Exp Ophthalmol. 2003;241:106–110. 5. Parrish RK, Schiffman JC, Feuer WJ, et al. Prognosis and risk factors for early postoperative wound leaks after trabeculectomy with and without 5-fluorouracil. Am J Ophthalmol. 2001; 132:633–640. 6. Henderson HWA, Ezra E, Murdoch IE. Early postoperative trabeculectomy leakage: incidence, time course, severity, and impact on surgical outcome. Br J Ophthalmol. 2004;88: 626–629. 7. Jampel HD, Musch DC, Gillespie BW, et al. Collaborative Initial Glaucoma Treatment Study Group. Perioperative complications of trabeculectomy in the collaborative initial
Copyright
r
8.
9.
10.
11.
12.
13.
14.
2014 Wolters Kluwer Health, Inc. All rights reserved.
glaucoma treatment study (CIGTS). Am J Ophthalmol. 2005; 140:16–22. Alwitry A, Rotchford A, Patel V, et al. Early bleb leak after trabeculectomy and prognosis for bleb failure. Eye. 2009;23: 858–863. Edmunds B, Thompson JR, Salmon JF, et al. The National Survey of Trabeculectomy. III. Early and late complications. Eye. 2002;16:297–303. Anand N, Arora S, Clowes M. Mitomycin C augmented glaucoma surgery: evolution of filtering bleb avascularity, transconjunctival oozing, and leaks. Br J Ophthalmol. 2006;90: 175–180. DeBry PW, Perkins TW, Heatley G, et al. Incidence of lateonset bleb-related complications following trabeculectomy with mitomycin. Arch Ophthalmol. 2002;120:297–300. Sharan S, Trope GE, Chipman M, et al. Late-onset bleb infections: prevalence and risk factors. Can J Ophthalmol. 2009;44:279–283. Solus JF, Jampel HD, Tracey PA, et al. Comparison of limbusbased and fornix-based trabeculectomy: success, bleb-related complications, and bleb morphology. Ophthalmology. 2012; 119:703–711. Realini T. Does Topical Medical Glaucoma Therapy Reduce Surgical Success? Glaucoma Today. 2003;1:3.
www.glaucomajournal.com |
Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
497
Risk Factors for a Severe Bleb Leak Following Trabeculectomy: A Retrospective Case-Control Study Chmielewska Karolina, MD, Catherine Baril, MD, Dominique Bourret-Massicotte, MD, Jean-Louis Anctil, MD, Louis Caron, MD, Annie Goyette, MD, and Be´atrice Des Marchais, MD, MSc
Purpose: To describe the population at risk of having a severe bleb leak needing a surgical repair in the operating room and to study risk factors associated with severe bleb leak. Patients and Methods: In this case-control study, 17 cases were enrolled and paired with 51 controls. We studied all patients having a surgical revision in our center for a severe bleb leak between January 1 and December 31, 2008. Three controls were paired to each case based on their surgery date. We then analyzed risk factors related to the patient, the intervention, and the postoperative follow-up. Results: Younger age was the only statistically significant risk factor for a severe bleb leak in our study. The odds of a severe bleb leak decreased as the age increased (P = 0.0029). In comparing the risk for a severe bleb leak in younger (below 55 y) versus patients aged 75 years or older, the odds ratio was 21.0. There were no statistically significant differences between cases and controls with respect to: type of glaucoma, number or types of previous ocular surgeries, number of preoperative topical medications, localization of the leak, localization of the wound (fornix or limbus-based), or the intraocular pressure on day 1 postoperative. Conclusions: Younger age at the time of trabeculectomy may be a risk factor for severe bleb leak. A trend was observed in which the patients under the age of 55 years were at greater risk for a severe bleb leak. Key Words: ophthalmology, glaucoma, filtering surgery, trabeculectomy
(J Glaucoma 2015;24:493–497)
D
espite the emergence of new surgical techniques for the treatment of glaucoma, trabeculectomy has remained the gold standard since the late 1960s. The procedure has evolved since then, especially with the introduction of antimetabolites. The use of antimetabolite agents such as mitomycin-C (MMC) and 5-fluorouracil (5-FU) in glaucoma filtering surgeries has greatly improved outcomes and is now Received for publication July 30, 2013; accepted August 11, 2014. From the Centre universitaire d’ophtalmologie et CUO-Recherche, Centre de recherche du CHU de Que´bec, Hoˆpital du Saint-Sacrement; De´partement d’ophtalmologie, Faculte´ de me´decine, Universite´ Laval, QC, Canada. Poster presentation of the study at ARVO Annual Meeting Association for Research in Vision and Ophthalmology, Fort Lauderdale, FL, May 7, 2012. Research projects in ophthalmology grant program from Pfizer was received for the conduct of this study. Pfizer was not involved in the study protocol nor publication decision. Disclosure: The authors declare no conflict of interest. Reprints: Be´atrice Des Marchais, MD, MSc, Centre universitaire d’ophtalmologie, Hoˆpital du St-Sacrement, 1050 ch. Sainte-Foy, QC G1S 4L8, Canada (e-mail: [email protected]). Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/IJG.0000000000000125
J Glaucoma
Volume 24, Number 7, September 2015
common practice in most Canadian centers. However, it is known that these agents increase the risks of hypotony, late bleb leaks, and endophtalmitis.1–4 Bleb leaks may occur early in the days following the surgery or even years later. The rate of these bleb leaks varies greatly between reports and is dependent on the length of the follow-up interval. Studies suggested that the rate of early bleb leak, occurring within 1 month of the surgery, is between 6% and 59%.5–9 Studies suggested that the reported incidence of late bleb leaks ranged from 2.9% to 24.6%, during a mean follow-up period of 36.5 months.1,10–12 With the use of antimetabolites, patients are now more carefully examined for leaks. Other than the use of antimetabolites, there is very little information about risk factors for bleb leaks. One review study identified the following risk factors for early bleb leak: Inferior location of conjunctival incision, One-layer closure, A history of ocular inflammatory disease, and, Older age at the time of surgery.5 Surgical approach also differentiated risk. A limbusbased procedure in contrast to a fornix-based procedure is a risk factor for leaks.8,13 Recently, Solus et al13 found limbus-based procedures were complicated by late bleb leaks, that is, significantly later than fornix-based procedures. In addition to the actual risk factors associated with surgery, postoperative manipulations in the office may also increase the risk of bleb leak. Surgeons often do suture lysis, needlings, or subconjunctival injections of antimetabolites to help reduce intraocular pressure or reduce the local inflammation. Each of these maneuvers may weaken the conjunctiva and hence increase the rate of bleb leaks. The impact of postoperative manipulations has not been extensively studied. One study showed no increase in bleb leaks within 1 month of the surgery,1 but little is known about late leaks associated with these postoperative manipulations. At our center, most leaks do not require repair in the operating room and can be managed in the office. Only persistent and severe leaks require repair in the operating room. The overall annual incidence of severe bleb leaks in our center is about 8.5%. This retrospective study was designed to describe the population at risk of having a severe bleb leak following a trabeculectomy, even years after initial surgery. We defined a severe bleb leak as a bleb leak requiring surgical repair in the operating room, because of few patients having severe bleb leaks in our center, we explored both early and severe bleb leaks.
PATIENTS AND METHODS A retrospective case-control study was conducted on patients who had undergone a surgical revision for a bleb www.glaucomajournal.com |
Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
493
Karolina et al
J Glaucoma
leak at our center between January 1 and December 31, 2008. Three controls were assigned for each case to increase the statistical power to detect a difference. As the number of cases is small, we acknowledge that this study is mainly descriptive and exploratory. The case group was composed of all the patients operated on at our center who had undergone a surgical revision for a severe bleb leak in our center between January 1 and December 31, 2008. Some of the main characteristics of the case group are presented in the Table 1. Only 1 patient was excluded from our study as the follow-up period was shorter than 2 months. The control group was composed of patients who had undergone a trabeculectomy by 1 of the 5 surgeons at our center but who did not have a bleb leak requiring surgical revision in the operating room. Each case was paired to 3 controls. All patients were operated on by 1 of the 5 glaucoma surgeons in our service. Controls were assigned to cases on the basis of the date of their surgery. Often, controls were operated on the same day but according to the statistician, a delay of up to 2 months between the surgery dates for cases and controls was acceptable to match controls to cases adequately. Only 1 control had a delay of >1 month between the surgery dates; all other controls were operated within 2 weeks of the corresponding case’s surgical date. When >3 controls were found for 1 case, 3 matching controls were randomly pooled and assigned to that one case. Our selection of controls as described above was a way to decrease bias in the technique, surgeon, assisting team, as well as materials and products used during any 1 trabeculectomy. Trabeculectomies were done to treat chronic open angle glaucoma, chronic angle closure glaucoma, mixed glaucoma, pigmentary dispersion glaucoma, normal tension glaucoma, pseudoexfoliation glaucoma, juvenile glaucoma, secondary glaucoma, increased episcleral venous pressure, and ocular hypertension (1 case of very high pressure uncontrolled by medical treatment). The surgical technique varies slightly from one surgeon to the other but generally included a fornix based flap, a squared scleral flap, an ostium with a punch, and closure with nylon 10-0 sutures. In this study, MMC was the only antimetabolite employed during trabeculectomy and it was used in all of our patients. Its concentration varied according to the route of delivery, that is, 0.1 mg/mL when injected subconjunctivally and 0.2 mg/mL when used on sponges applied to the sclera. The application duration of the sponges to the surgical site varied from 30 seconds to 3.5 minutes. Thirteen patients received a subconjunctival injection intraoperatively only (without adding MMC sponges’ applications); 5 patients were in the case cohort and 8 patients were in the control cohort. A patient was excluded from our study if the follow-up period was 1 month postoperatively, which differs from our current study in which late bleb leaks were included. As mentioned earlier, 6 patients suffered from a severe bleb leak 4 weeks or more after the surgery, and 2 of theses had a leak appear at 52 weeks or later postoperatively. The mean age in these patients was 62 years, no different than in the rest of the cases. The number of severe bleb leaks was too small to conclude that sex, surgical technique, and the type of glaucoma were risks factors. However, the case group had a tendency to have more patients with a fornix-based wound and a lesser proportion of women, although this was not statistically significant. In our study, the number of preoperative topical medications did not show an increased number of leaks. However, we did not have the information regarding the duration of topical treatment in our patients. It is now known that long-term treatment with topical agents may alter the conjunctiva, and hence increase complications such as leaks.14 We did not, however, look into this variable in this study. The present study found no significant risk associated with postoperative manipulations that contributed to the incidence of leaks. However, because of the exploratory nature of the current study, no conclusions can be reached regarding these risk factors. The patients with a late leak did not appear to be subject to more manipulations (needlings) that could have adversely affected the conjunctiva. Further, it is interesting to see that as the number of surgical repairs at the slit-lamp did not increase the odds of having a severe bleb leak, we therefore cannot yet define precise factors that should guide us to do an extensive repair in the operating room early after we find the leak. It is already known that for cystic avascular blebs that would result in a late leak, simple suturing does not usually resolve the problem. In our study 5 patients did not receive sutures in the clinic. A few patients had an avascular bleb that caused the surgeons to fear that simple suturing would fail to fix the leak, and possibly increase it due to its fragility.
Although the present study failed to show a significant difference between simple and combined surgery, one could suggest that there was a tendency to have more bleb leaks when cataract extraction was combined with trabeculectomy. One study shows that trabeculectomy alone seemed to have a higher risk of bleb leak than when combined with a cataract extraction.1 Our sample size may be too small to draw inferences or conclusions. We also looked at the number of patients who achieved an intraocular pressure below 15 mm Hg without any medications in each group and also found no statistically significant difference. However, this study was not powered to analyze the success of trabeculectomy in patients having a severe bleb leak leading to surgical revision in the operating room. Finally, all patients in the present study were operated on at the same center. This was very helpful in collecting data and diminishing confounding variables such as differences in the surgical support staff or differences in materials used. All of our glaucoma surgeons used a very similar method and similar values regarding concentration and the duration time of MMC administration (and no patients received 5-FU). As mentioned earlier, three controls were paired to one case on the basis of the surgical date to enable us to detect small differences if they existed. The results of this study suggest that younger age at the time of trabeculectomy (below 55 y of age) may be a risk factor for severe bleb leak. A trend was observed in which the younger the age of the patient, the greater the risk of the bleb leak. Our study included early and late bleb leaks; risk factors for each of these two categories might be different. As this study is mainly descriptive and exploratory, other larger prospective series will be needed to help define the specific risk factors in younger patients that may predispose them to early or late bleb leak leading to surgical repair in the operating room.
ACKNOWLEDGMENTS The authors thank Mrs Nathalie Laflamme, PhD, and Mr Paul-Marie Bernard for theirs statistical assistance and Mrs Marcelle Giasson for research coordinator assistance.
496 | www.glaucomajournal.com Copyright r 2014 Wolters Kluwer Health, Inc. All rights reserved. Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
J Glaucoma
Volume 24, Number 7, September 2015
Severe Bleb Leak Following Trabeculectomy
REFERENCES 1. Greenfield DS, Liebmann JM, Jee J, et al. Late-onset bleb leaks after glaucoma filtering surgery. Arch Ophthalmol. 1998; 116:443–447. 2. Wilkins M, Indar A, Wormald R. Intra-operative mitomycin C for glaucoma surgery. Cochrane Database Syst Rev. 2005;19: CD002897. 3. The Fluorouracil Filtering Surgery Group. Five-year follow-up of the Fluorouracil Filtering Surgery Study. Am J Ophthalmol. 1996;121:349–366. 4. Beckers HJ, Kinders KC, Webers CA. Five-year results of trabeculectomy with mitomycin C. Graefes Arch Clin Exp Ophthalmol. 2003;241:106–110. 5. Parrish RK, Schiffman JC, Feuer WJ, et al. Prognosis and risk factors for early postoperative wound leaks after trabeculectomy with and without 5-fluorouracil. Am J Ophthalmol. 2001; 132:633–640. 6. Henderson HWA, Ezra E, Murdoch IE. Early postoperative trabeculectomy leakage: incidence, time course, severity, and impact on surgical outcome. Br J Ophthalmol. 2004;88: 626–629. 7. Jampel HD, Musch DC, Gillespie BW, et al. Collaborative Initial Glaucoma Treatment Study Group. Perioperative complications of trabeculectomy in the collaborative initial
Copyright
r
8.
9.
10.
11.
12.
13.
14.
2014 Wolters Kluwer Health, Inc. All rights reserved.
glaucoma treatment study (CIGTS). Am J Ophthalmol. 2005; 140:16–22. Alwitry A, Rotchford A, Patel V, et al. Early bleb leak after trabeculectomy and prognosis for bleb failure. Eye. 2009;23: 858–863. Edmunds B, Thompson JR, Salmon JF, et al. The National Survey of Trabeculectomy. III. Early and late complications. Eye. 2002;16:297–303. Anand N, Arora S, Clowes M. Mitomycin C augmented glaucoma surgery: evolution of filtering bleb avascularity, transconjunctival oozing, and leaks. Br J Ophthalmol. 2006;90: 175–180. DeBry PW, Perkins TW, Heatley G, et al. Incidence of lateonset bleb-related complications following trabeculectomy with mitomycin. Arch Ophthalmol. 2002;120:297–300. Sharan S, Trope GE, Chipman M, et al. Late-onset bleb infections: prevalence and risk factors. Can J Ophthalmol. 2009;44:279–283. Solus JF, Jampel HD, Tracey PA, et al. Comparison of limbusbased and fornix-based trabeculectomy: success, bleb-related complications, and bleb morphology. Ophthalmology. 2012; 119:703–711. Realini T. Does Topical Medical Glaucoma Therapy Reduce Surgical Success? Glaucoma Today. 2003;1:3.
www.glaucomajournal.com |
Copyright r 2015 Wolters Kluwer Health, Inc. All rights reserved.
497
