LETTERS
Hypertensive Phase Following Silicon Plate Ahmed Glaucoma Valve Implantation To the Editor: We read with interest the article titled, “Hypertensive Phase Following Silicone Plate Ahmed Glaucoma Valve Implantation” by Hun Jae Won and Kyung Rim Sung.1 In this wellorganized study, the author had investigated about incidence and risk factors for developing hypertensive phase (HP) following silicon plate Ahmed glaucoma valve (AGV) implantation. We appreciate the author’s effort and research work. The results have also been discussed very well. HP is a phenomenon of common occurrence following AGV implantation and has been reported up to 80% in various studies.2,3 We would like to share our personal experience of AGV implantation in a series of 61 patients. We found a higher incidence (63.93%) of HP in our series as compared with the present study (31.1%). This could be because of higher percentage (75.4%) of secondary refractory glaucoma with uncontrolled intraocular pressure (IOP) in our series. Encapsulation of the plate early in the postoperative period is thought to be responsible for this early rise in IOP.4 Proinflammatory cytokines are found at higher levels in aqueous of the eyes with encapsulated blebs and higher IOP.5 Therefore, the eyes with secondary refractory glaucoma such as neovascular glaucoma, glaucoma following keratoplasty, and postvitreoretinal surgery, etc. with chronic inflammation have higher chance of developing HP. We agree with the author’s interpretation of the current study that higher preoperative IOP was associated with the HP development. However, we also found aphakia as a risk factor for HP in our series, with 92.85% (13 of the 14) aphakic patients developing HP.
Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000544
TO THE
EDITOR
In our series, HP resolved by the end of 6 months in 92.86% patients; however, only 17.86% patients were completely off medications. Patients undergoing AGV implantation need frequent follow-up in early postoperative period to reduce the incidence of IOP spikes. Complete success rate of AGV implant is limited in patients who develop HP. Various methods have been tried to increase the success rate, such as the use of early aqueous suppressant therapy6 and digital massage7 in patients who develop HP. However, by far this is definitely a well-conducted study with large sample size. This study definitely tells us about the importance of preventing early postoperative IOP spikes to achieve higher complete success rate.
Suneeta Dubey, Dushyant K. Sharma, MBBS, Madhu Bhoot, Julie Pegu, Monica Gandhi,
MS MS MS MS MS
Dr Shroff’s Charity Eye Hospital Delhi, India
REFERENCES 1. Won HJ, Sung KR. Hypertensive phase following silicone plate Ahmed glaucoma valve implantation. J Glaucoma. 2016;25: e313–e317. 2. Ayyala RS, Zurakowski D, Smith JA, et al. A clinical study of the Ahmed glaucoma valve implant in advanced glaucoma. Ophthalmology. 1998;105: 1968–1976. 3. Nouri-Mahdavi K, Caprioli J. Evaluation of the hypertensive phase after insertion of the Ahmed glaucoma valve. Am J Ophthalmol. 2003;136:1001–1008. 4. Thieme H, Choritz L, HofmannRummelt C, et al. Histopathologic findings in early encapsulated blebs of young patients treated with the Ahmed glaucoma valve. J Glaucoma. 2011;20: 246–251. 5. Freedman J, Iserovich P. Proinflammatory cytokines in glaucomatous aqueous and encysted Molteno implant blebs and their relationship to pressure. Invest Ophthalmol Vis Sci. 2013;54: 4851–4855. 6. Law SK, Kornmann HL, JoAnn A, et al. Early aqueous suppressant therapy on hypertensive phase following glaucoma drainage device procedure: a randomized prospective trial. J Glaucoma. 2016;25: 248–257.
7. Smith M, Geffen N, Alasbali T, et al. Digital ocular massage for hypertensive phase after Ahmed valve surgery. J Glaucoma. 2010;19: 11–14.
In Reply: I greatly appreciate the interest Dr Sharma has shown in our article entitled “Hypertensive phase (HP) following silicon plate Ahmed glaucoma valve (AGV) implantation.”1 With regard to the incidence of HP, 31.1% of the participants developed HP in our series; this incidence was lower than that reported by other studies or by Dr Sharma’s analysis.2,3 As mentioned in our paper, HP may be less frequent after silicone plate AGV implantation. However, I agree with Dr Sharma’s comment that a higher percentage of secondary refractory glaucoma with uncontrolled intraocular pressure (IOP) in his series may have contributed to the variation in outcomes. Although direct comparison of the pre-AGV implantation diagnosis between this study and that of Dr Sharma would be difficult, our series may have a lower percentage of patients with secondary refractory glaucoma. For example, he had 14 aphakic patients and found that aphakia was a risk factor for HP development; in contrast, our series had 3 cases of aphakia. In our multivariate analysis, higher IOP before AGV implantation was the most significant risk factor; however, secondary refractory cases tended to have higher IOP. Therefore, our results may support Dr Sharma’s suggestion. A significant finding is that only 23% of our patients who developed HP could be completely weaned off the medication at postoperative 1 year; additionally, Dr Sharma mentioned that only 17.86% of their patients were completely weaned off the medications at 6 months postoperatively. Hence, patients who experience HP may need intensive postoperative IOP-lowering medication, although increased use of IOP-lowering medication in the HP group may be explained by the trend for continued use of IOP-lowering medication despite achieving IOP Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000563
e124 | www.glaucomajournal.com J Glaucoma Volume 26, Number 3, March 2017 Copyright r 2017 Wolters Kluwer Health, Inc. All rights reserved.
J Glaucoma
Volume 26, Number 3, March 2017
control; this may be due to the concern of IOP elevation after cessation of medication. Finally, we agree that the success rate of AGV implantation is limited in patients who develop HP; thus, detection and appropriate care of HP are critical for patients who undergo AGV implantation for refractory glaucoma. Kyung Rim Sung, MD, PhD*w *Department of Ophthalmology, College of Medicine, University of Ulsan, Uslan wAsan Medical Center, Seoul, Korea
REFERENCES 1. Won HJ, Sung KR. Hypertensive phase following silicone plate Ahmed glaucoma valve implantation. J Glaucoma. 2016;25:e124–e125. 2. Ayyala RS, Zurakowski D, Smith JA, et al. A clinical study of the Ahmed valve implant in advanced glaucoma. Ophthalmology. 1998;105:1968–1976. 3. Nouri-Mahdavi K, Caprioli J. Evaluation of the hypertensive phase after insertion the Ahmed glaucoma valve. Am J Ophthalmol. 2003;136:1001–1008.
Comparing Gonioscopy With Visante and Cirrus Optical Coherence Tomography for Anterior Chamber Angle Assessment in Glaucoma Patients In Reply: We reviewed the article published online ahead of print in May 2014 by Hu et al1 titled “Comparing gonioscopy with Visante and Cirrus optical coherence tomography for anterior chamber angle assessment in glaucoma patients” in our glaucoma journal club at McGovern Medical School at The University of Texas Health Science Center (UTHealth). The article raises Supported in part by National Eye Institute Vision Core Grant P30EY010608, a Challenge Grant to McGovern Medical School from Research to Prevent Blindness, and the Hermann Eye Fund.Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000451
Copyright
r
Letters to the Editor
the interesting concept of using anterior segment ocular coherence tomography (ASOCT) to assess the presence of angle closure compared with gonioscopy. The authors report that when visualizing the anterior chamber angle with the Visante or Cirrus, there were 89/200 and 100/200 quadrants, respectively, where the scleral spur was not visible. Subsequently, there were 86/200 (43%) quadrants and 95/200 (48%) quadrants, respectively, wherein angle closure could not be determined. The authors state in the discussion that the discrepancy in results was because they were unable to classify angles as closed without identifying angle structures. Of these quadrants, 33 quadrants and 39 quadrants were the superior quadrant,1 respectively, which is the narrowest quadrant on gonioscopic examination.2–4 In the results section, the authors state that, “all angles wherein closure was unable to be determined were excluded from this analysis,”1 indicating the elimination of 66% and 78% of the superior angle data from analysis. Further, the remaining data used to determine the agreement between gonioscopy and ASOCT were calculated by quadrant, not by eye.1 Because gonioscopy graded mainly superior angles and the ASOCT graded mainly the nasal or temporal angles, presenting the data in this manner misrepresents the concordance of gonioscopy to the Visante and Cirrus in determining the presence of angle closure. Because quadrants were not paired for analysis, that is, superior angle on gonioscopy to superior angle on ASOCT, omitting this data from analysis and evaluating the agreement between gonioscopy and ASOCT by quadrant rather than eye is significant to the interpretation of the results and makes the study appear more robust than it actually is. In addition, it is often more difficult to identify angle structures in narrow angle eyes on ASOCT,5 which may skew the results away from the narrow angle population. A more complete discussion of the methods and data analysis may be warranted.
Mallika K. Doss, Lauren S. Blieden, David A. Lee, Nicholas P. Bell, Robert M. Feldman,
MD*w MD*w MD*w MD*w MD*w
*Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth) wRobert Cizik Eye Clinic, Houston, TX
2016 Wolters Kluwer Health, Inc. All rights reserved.
REFERENCES 1. Hu CX, Mantravadi A, Zangalli C, et al. Comparing gonioscopy with Visante and Cirrus optical coherence tomography for anterior chamber angle assessment in glaucoma patients. J Glaucoma. 2016; 25:177–183. 2. Rigi M, Blieden LS, Nguyen D, et al. Trabecular-iris circumference volume in open angle eyes using swept-source fourier domain anterior segment optical coherence tomography. J Ophthalmol. 2014;2014:590978. 3. Liu S, Yu M, Ye C, et al. Anterior chamber angle imaging with sweptsource optical coherence tomography: an investigation on variability of angle measurement. Invest Ophthalmol Vis Sci. 2011;52:8598–8603. 4. Cumba RJ, Radhakrishnan S, Bell NP, et al. Reproducibility of scleral spur identification and angle measurements using fourier domain anterior segment optical coherence tomography. J Ophthalmol. 2012;2012:487309. 5. Sakata LM, Lavanya R, Friedman DS, et al. Assessment of the scleral spur in anterior segment optical coherence tomography images. Arch Ophthalmol. 2008;126:181–185.
In Reply: We welcome the interest and comments from Drs Doss, Blieden, Lee, Bell, and Feldman in our study entitled “Comparing Gonioscopy With Visante and Cirrus Optical Coherence Tomography for Anterior Chamber Angle Assessment in Glaucoma Patients.”1 We note their concern with our methodology and findings, particularly regarding our agreement analysis for angle closure between the 3 devices [gonioscopy, Visante anterior segment optical coherence tomography (OCT) and Cirrus high definition OCT]. Analysis of angle closure agreement was performed using Cohen k (K). All angles wherein closure was unable to be determined were excluded from analysis. If angle closure was unable to be determined with Visante in a superior angle, then the angle grading for the same quadrant using gonioscopy was also removed from agreement analysis. The same was true
Supported by The Mentoring for Advancement of Physician-Scientists (MAPS) Award of the American Glaucoma Society and the Wills Eye Hospital Innovation Award. Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000452
www.glaucomajournal.com |
Copyright r 2017 Wolters Kluwer Health, Inc. All rights reserved.
e125
Hypertensive Phase Following Silicon Plate Ahmed Glaucoma Valve Implantation To the Editor: We read with interest the article titled, “Hypertensive Phase Following Silicone Plate Ahmed Glaucoma Valve Implantation” by Hun Jae Won and Kyung Rim Sung.1 In this wellorganized study, the author had investigated about incidence and risk factors for developing hypertensive phase (HP) following silicon plate Ahmed glaucoma valve (AGV) implantation. We appreciate the author’s effort and research work. The results have also been discussed very well. HP is a phenomenon of common occurrence following AGV implantation and has been reported up to 80% in various studies.2,3 We would like to share our personal experience of AGV implantation in a series of 61 patients. We found a higher incidence (63.93%) of HP in our series as compared with the present study (31.1%). This could be because of higher percentage (75.4%) of secondary refractory glaucoma with uncontrolled intraocular pressure (IOP) in our series. Encapsulation of the plate early in the postoperative period is thought to be responsible for this early rise in IOP.4 Proinflammatory cytokines are found at higher levels in aqueous of the eyes with encapsulated blebs and higher IOP.5 Therefore, the eyes with secondary refractory glaucoma such as neovascular glaucoma, glaucoma following keratoplasty, and postvitreoretinal surgery, etc. with chronic inflammation have higher chance of developing HP. We agree with the author’s interpretation of the current study that higher preoperative IOP was associated with the HP development. However, we also found aphakia as a risk factor for HP in our series, with 92.85% (13 of the 14) aphakic patients developing HP.
Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000544
TO THE
EDITOR
In our series, HP resolved by the end of 6 months in 92.86% patients; however, only 17.86% patients were completely off medications. Patients undergoing AGV implantation need frequent follow-up in early postoperative period to reduce the incidence of IOP spikes. Complete success rate of AGV implant is limited in patients who develop HP. Various methods have been tried to increase the success rate, such as the use of early aqueous suppressant therapy6 and digital massage7 in patients who develop HP. However, by far this is definitely a well-conducted study with large sample size. This study definitely tells us about the importance of preventing early postoperative IOP spikes to achieve higher complete success rate.
Suneeta Dubey, Dushyant K. Sharma, MBBS, Madhu Bhoot, Julie Pegu, Monica Gandhi,
MS MS MS MS MS
Dr Shroff’s Charity Eye Hospital Delhi, India
REFERENCES 1. Won HJ, Sung KR. Hypertensive phase following silicone plate Ahmed glaucoma valve implantation. J Glaucoma. 2016;25: e313–e317. 2. Ayyala RS, Zurakowski D, Smith JA, et al. A clinical study of the Ahmed glaucoma valve implant in advanced glaucoma. Ophthalmology. 1998;105: 1968–1976. 3. Nouri-Mahdavi K, Caprioli J. Evaluation of the hypertensive phase after insertion of the Ahmed glaucoma valve. Am J Ophthalmol. 2003;136:1001–1008. 4. Thieme H, Choritz L, HofmannRummelt C, et al. Histopathologic findings in early encapsulated blebs of young patients treated with the Ahmed glaucoma valve. J Glaucoma. 2011;20: 246–251. 5. Freedman J, Iserovich P. Proinflammatory cytokines in glaucomatous aqueous and encysted Molteno implant blebs and their relationship to pressure. Invest Ophthalmol Vis Sci. 2013;54: 4851–4855. 6. Law SK, Kornmann HL, JoAnn A, et al. Early aqueous suppressant therapy on hypertensive phase following glaucoma drainage device procedure: a randomized prospective trial. J Glaucoma. 2016;25: 248–257.
7. Smith M, Geffen N, Alasbali T, et al. Digital ocular massage for hypertensive phase after Ahmed valve surgery. J Glaucoma. 2010;19: 11–14.
In Reply: I greatly appreciate the interest Dr Sharma has shown in our article entitled “Hypertensive phase (HP) following silicon plate Ahmed glaucoma valve (AGV) implantation.”1 With regard to the incidence of HP, 31.1% of the participants developed HP in our series; this incidence was lower than that reported by other studies or by Dr Sharma’s analysis.2,3 As mentioned in our paper, HP may be less frequent after silicone plate AGV implantation. However, I agree with Dr Sharma’s comment that a higher percentage of secondary refractory glaucoma with uncontrolled intraocular pressure (IOP) in his series may have contributed to the variation in outcomes. Although direct comparison of the pre-AGV implantation diagnosis between this study and that of Dr Sharma would be difficult, our series may have a lower percentage of patients with secondary refractory glaucoma. For example, he had 14 aphakic patients and found that aphakia was a risk factor for HP development; in contrast, our series had 3 cases of aphakia. In our multivariate analysis, higher IOP before AGV implantation was the most significant risk factor; however, secondary refractory cases tended to have higher IOP. Therefore, our results may support Dr Sharma’s suggestion. A significant finding is that only 23% of our patients who developed HP could be completely weaned off the medication at postoperative 1 year; additionally, Dr Sharma mentioned that only 17.86% of their patients were completely weaned off the medications at 6 months postoperatively. Hence, patients who experience HP may need intensive postoperative IOP-lowering medication, although increased use of IOP-lowering medication in the HP group may be explained by the trend for continued use of IOP-lowering medication despite achieving IOP Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000563
e124 | www.glaucomajournal.com J Glaucoma Volume 26, Number 3, March 2017 Copyright r 2017 Wolters Kluwer Health, Inc. All rights reserved.
J Glaucoma
Volume 26, Number 3, March 2017
control; this may be due to the concern of IOP elevation after cessation of medication. Finally, we agree that the success rate of AGV implantation is limited in patients who develop HP; thus, detection and appropriate care of HP are critical for patients who undergo AGV implantation for refractory glaucoma. Kyung Rim Sung, MD, PhD*w *Department of Ophthalmology, College of Medicine, University of Ulsan, Uslan wAsan Medical Center, Seoul, Korea
REFERENCES 1. Won HJ, Sung KR. Hypertensive phase following silicone plate Ahmed glaucoma valve implantation. J Glaucoma. 2016;25:e124–e125. 2. Ayyala RS, Zurakowski D, Smith JA, et al. A clinical study of the Ahmed valve implant in advanced glaucoma. Ophthalmology. 1998;105:1968–1976. 3. Nouri-Mahdavi K, Caprioli J. Evaluation of the hypertensive phase after insertion the Ahmed glaucoma valve. Am J Ophthalmol. 2003;136:1001–1008.
Comparing Gonioscopy With Visante and Cirrus Optical Coherence Tomography for Anterior Chamber Angle Assessment in Glaucoma Patients In Reply: We reviewed the article published online ahead of print in May 2014 by Hu et al1 titled “Comparing gonioscopy with Visante and Cirrus optical coherence tomography for anterior chamber angle assessment in glaucoma patients” in our glaucoma journal club at McGovern Medical School at The University of Texas Health Science Center (UTHealth). The article raises Supported in part by National Eye Institute Vision Core Grant P30EY010608, a Challenge Grant to McGovern Medical School from Research to Prevent Blindness, and the Hermann Eye Fund.Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000451
Copyright
r
Letters to the Editor
the interesting concept of using anterior segment ocular coherence tomography (ASOCT) to assess the presence of angle closure compared with gonioscopy. The authors report that when visualizing the anterior chamber angle with the Visante or Cirrus, there were 89/200 and 100/200 quadrants, respectively, where the scleral spur was not visible. Subsequently, there were 86/200 (43%) quadrants and 95/200 (48%) quadrants, respectively, wherein angle closure could not be determined. The authors state in the discussion that the discrepancy in results was because they were unable to classify angles as closed without identifying angle structures. Of these quadrants, 33 quadrants and 39 quadrants were the superior quadrant,1 respectively, which is the narrowest quadrant on gonioscopic examination.2–4 In the results section, the authors state that, “all angles wherein closure was unable to be determined were excluded from this analysis,”1 indicating the elimination of 66% and 78% of the superior angle data from analysis. Further, the remaining data used to determine the agreement between gonioscopy and ASOCT were calculated by quadrant, not by eye.1 Because gonioscopy graded mainly superior angles and the ASOCT graded mainly the nasal or temporal angles, presenting the data in this manner misrepresents the concordance of gonioscopy to the Visante and Cirrus in determining the presence of angle closure. Because quadrants were not paired for analysis, that is, superior angle on gonioscopy to superior angle on ASOCT, omitting this data from analysis and evaluating the agreement between gonioscopy and ASOCT by quadrant rather than eye is significant to the interpretation of the results and makes the study appear more robust than it actually is. In addition, it is often more difficult to identify angle structures in narrow angle eyes on ASOCT,5 which may skew the results away from the narrow angle population. A more complete discussion of the methods and data analysis may be warranted.
Mallika K. Doss, Lauren S. Blieden, David A. Lee, Nicholas P. Bell, Robert M. Feldman,
MD*w MD*w MD*w MD*w MD*w
*Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth) wRobert Cizik Eye Clinic, Houston, TX
2016 Wolters Kluwer Health, Inc. All rights reserved.
REFERENCES 1. Hu CX, Mantravadi A, Zangalli C, et al. Comparing gonioscopy with Visante and Cirrus optical coherence tomography for anterior chamber angle assessment in glaucoma patients. J Glaucoma. 2016; 25:177–183. 2. Rigi M, Blieden LS, Nguyen D, et al. Trabecular-iris circumference volume in open angle eyes using swept-source fourier domain anterior segment optical coherence tomography. J Ophthalmol. 2014;2014:590978. 3. Liu S, Yu M, Ye C, et al. Anterior chamber angle imaging with sweptsource optical coherence tomography: an investigation on variability of angle measurement. Invest Ophthalmol Vis Sci. 2011;52:8598–8603. 4. Cumba RJ, Radhakrishnan S, Bell NP, et al. Reproducibility of scleral spur identification and angle measurements using fourier domain anterior segment optical coherence tomography. J Ophthalmol. 2012;2012:487309. 5. Sakata LM, Lavanya R, Friedman DS, et al. Assessment of the scleral spur in anterior segment optical coherence tomography images. Arch Ophthalmol. 2008;126:181–185.
In Reply: We welcome the interest and comments from Drs Doss, Blieden, Lee, Bell, and Feldman in our study entitled “Comparing Gonioscopy With Visante and Cirrus Optical Coherence Tomography for Anterior Chamber Angle Assessment in Glaucoma Patients.”1 We note their concern with our methodology and findings, particularly regarding our agreement analysis for angle closure between the 3 devices [gonioscopy, Visante anterior segment optical coherence tomography (OCT) and Cirrus high definition OCT]. Analysis of angle closure agreement was performed using Cohen k (K). All angles wherein closure was unable to be determined were excluded from analysis. If angle closure was unable to be determined with Visante in a superior angle, then the angle grading for the same quadrant using gonioscopy was also removed from agreement analysis. The same was true
Supported by The Mentoring for Advancement of Physician-Scientists (MAPS) Award of the American Glaucoma Society and the Wills Eye Hospital Innovation Award. Disclosure: The authors declare no conflict of interest. DOI: 10.1097/IJG.0000000000000452
www.glaucomajournal.com |
Copyright r 2017 Wolters Kluwer Health, Inc. All rights reserved.
e125
