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Clinical and Experimental Ophthalmology 2014; 42: 883–905 doi: 10.1111/ceo.12322
Letters to the Editor Novel technique for posterior placement of mitomycin-soaked sponges in glaucoma surgery An intraoperative antimetabolite such as mitomycin C is widely used in trabeculectomy to decrease the risk of bleb failure secondary to subconjunctival scarring. A larger mitomycin C treatment area appears advantageous in terms of achieving and maintaining target intraocular pressure.1 A posterior bleb located completely under the upper lid reduces the risk of leak and infection, prevents cystic bleb formation and improves patient comfort.2 Recent studies have investigated methods to deliver large-area antimetabolite treatment in a safe and reliable way.3 A common technique of applying antimetabolite to Tenon’s capsule and sclera uses Moorfield forceps to introduce mitomycin C-soaked sponges into the dissected subconjunctival space. The grooved tips on the Moorfields forceps often become caught and preclude accurate positioning of the sponges. We have developed a method for effective antimetabolite application using sponges secured with a nylon suture4 and Monarch lens loading forceps (Alcon/Grieshaber, Fort Worth, TX, USA). In our trabeculectomy technique, a fornix-based conjunctival flap is dissected and a half-thickness scleral flap is cut. The antimetabolite is applied after creating the scleral flap and before entering the eye. Mitomycin C is applied at concentrations between 0.02% and 0.04% on five 5 × 8 mm microsurgical sponges, each secured with a single 6-0 silk suture as per a previously published method.4 Monarch lens loading forceps are used to easily and accurately place the sponges into the posterior superotemporal and superonasal subconjunctival space. We aim to treat a large area, as posterior as possible, including under the scleral flap. After a treatment time of 3 min, the sponges are removed with the Monarch forceps, and the scleral surface and conjunctiva are extensively rinsed with balanced salt solution (Alcon). This modification of a standard trabeculectomy technique2 is simple and uses inexpensive and readily available equipment. The use of Monarch forceps allows accurate insertion of antimetabolite-soaked sponges into the posterior subconjunctival space to achieve a large treatment area. The smooth forcep tips mean the sponges are released easily into their desired location and they are removed quickly by grasping the attached sutures, avoiding inconsistencies in duration of drug delivery. Inadvertent exposure of the cut edge of the conjunctiva to antimetabolite from anteriorly placed sponges is also able
to be avoided, decreasing the risk of wound leak and dehiscence.2
Kate Leahy BMed,1 Wendy Whittles RN2 and Andrew White PhD FRANZCO1,2,3,4 1 Westmead Hospital, Westmead, 2Parramatta Eye Hospital, Parramatta, 3Centre for Vision Research, Westmead Millennium Institute, and 4Save Sight Institute, University of Sydney, Sydney, New South Wales, Australia Received 1 March 2014; accepted 8 March 2014.
REFERENCES 1. Önol M, Aktas¸ Z, Hasanreisog˘lu B. Enhancement of the success rate in trabeculectomy: large-area mitomycin-C application. Clin Experiment Ophthalmol 2008; 36: 316–22. 2. Khaw P, Dahlmann-Noor A, Mireskandari K. Trabeculectomy technique. Glaucoma Today 2005; 3: 22–9. 3. Healey P, Crowston J. Trypan blue identifies antimetabolite treatment area in trabeculectomy. Br J Ophthalmol 2005; 89: 1152–6. 4. Knape RM, Smith MF. Antimetabolite application technique in trabeculectomy surgery. Clin Experiment Ophthalmol 2011; 39: 580–1.
Primary selective laser trabeculoplasty: a cautionary tale Selective laser trabeculoplasty (SLT) is an established treatment for ocular hypertension (OHT) or open-angle glaucoma as it produces a clinically meaningful intraocular pressure (IOP) reduction with a favourable safety profile. There is an increasing trend to offer SLT as primary therapy; this is supported by clinical trial data showing prostaglandin monotherapy and SLT have equal efficacy.1 However, we would like to draw attention to an important aspect of patient management when administering SLT as primary therapy for glaucoma. A 59-year-old male with a known history of OHT (baseline IOP right [R] 25 mmHg, left [L] 19 mmHg; central corneal thickness R 488 μm, L 506 μm; cup-to-disc ratio [CDR] R and L 0.6; full field on automated perimetry; normal retinal nerve fibre layer optical coherence tomography [OCT]) was offered right SLT as an alternative to latanoprost monotherapy which had been trialled without success. A right SLT was performed (0.4–0.6 mJ × 360 degrees) with IOP reducing to 21 mmHg post-SLT.
Competing/conflicts of interest: No stated conflict of interest. Funding sources: No stated funding sources. Competing/conflicts of interest: No stated conflict of interest. Funding sources: No stated funding sources. © 2014 Royal Australian and New Zealand College of Ophthalmologists
884
Letters to the Editor
(a)
(b)
30
(c)
30
(d)
The patient was lost to follow up for four years until he was urgently referred back by his optometrist. Repeat examination revealed IOPs of R 24 mmHg and L 18 mmHg with glaucomatous optic neuropathy (CDR R 0.8 and L 0.6) (Fig. 1d). OCT demonstrated retinal nerve fibre layer thinning bilaterally and automated perimetry showed a right superior arcuate defect (Fig. 1b). He had not seen another ophthalmologist in the four years since last review and was not taking topical antihypertensive therapy. The patient informed us that since his IOP had fallen with SLT treatment, he felt he did not need further treatment or review. This case highlights the risk that primary SLT is perceived by some patients to be a definitive or curative treatment. Without the need to regularly use glaucoma eye drops, patients may forget the potential threat of glaucoma and/or underestimate the need for regular surveillance and further intervention. Our patient felt the SLT had cured his OHT; he was not aware of the diminishing effect of SLT over time and the importance of long-term monitoring for glaucoma development. Regular review could have prevented glaucoma onset or identified its development at an earlier stage in this case. Prospective studies of the long-term effects of SLT demonstrate that its IOP-lowering effect falls over time. Bovell et al.2 published a long-term evaluation of participants from an original 12-month duration randomized controlled trial. The percentage of patients at one year maintaining a 20% IOP reduction (without supplementary medical, surgical or laser intervention) was approximately 60%, at two years it was 50%, and by five years this had fallen to 25%. There has been a rapid uptake of SLT amongst ophthalmologists3,4 based on many factors including the potential to circumvent the issue of patient non-adherence associated with topical antihypertensive therapy. However, as our case
Figure 1. Humphrey Visual Field grey scale and red-free fundus photographs of the right eye. Compared to the normal field at the time of SLT (a), there is a nasal step and superior partial arcuate defect at follow up four years later (b). Comparison of red-free fundus photographs at the time of SLT (c) and four years later (d) shows enlargement of the cup-to-disc ratio, loss of neuroretinal rim and an inferotemporal retinal nerve fibre layer defect (arrows) at follow up.
demonstrates, these benefits may be offset by nonattendance at review because of a false impression that treatment is curative. To address this problem, it is important that ophthalmologists include in their consent a discussion about the importance of long-term follow up of patients. This should include emphasis on the variable duration of treatment effect of SLT in some patients, and the potential need for repeat procedures or additional therapy.
Shweta Kaushik BMed PhD,1 Ross Ferrier FRANZCO2 and Colin Clement PhD FRANZCO2,3 1 Glaucoma Unit, Westmead Hospital, Sydney, 2Wyong Eye Surgery, Wyong, New South Wales, and 3Glaucoma Unit, Sydney Eye Hospital, Sydney, Australia Received 6 March 2014; accepted 13 March 2014.
REFERENCES 1. Katz LJ, Steinmann WC, Kabir A et al. Selective laser trabeculoplasty versus medical therapy as initial treatment of glaucoma: a prospective, randomized trial. J Glaucoma 2012; 21; 460–8. 2. Bovell AM, Damji KF, Hodge WG, Rock WJ, Buhrman RR, Pan YI. Long term effects on the lowering of intraocular pressure: selective laser or argon laser trabeculoplasty? Can J Ophthalmol 2011; 46: 408–13. 3. Ramulu PY, Corcoran KJ, Corcoran SL, Robin AL. Utilization of various glaucoma surgeries and procedures in Medicare beneficiaries from 1995 to 2004. Ophthalmology 2007; 114: 2265–70. 4. Rachmiel R, Trope GE, Chipman ML, Gouws P, Buys YM. Laser trabeculoplasty trends with the introduction of new medical treatments and selective laser trabeculoplasty. J Glaucoma 2006; 15: 306–9.
© 2014 Royal Australian and New Zealand College of Ophthalmologists
Copyright of Clinical & Experimental Ophthalmology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Clinical and Experimental Ophthalmology 2014; 42: 883–905 doi: 10.1111/ceo.12322
Letters to the Editor Novel technique for posterior placement of mitomycin-soaked sponges in glaucoma surgery An intraoperative antimetabolite such as mitomycin C is widely used in trabeculectomy to decrease the risk of bleb failure secondary to subconjunctival scarring. A larger mitomycin C treatment area appears advantageous in terms of achieving and maintaining target intraocular pressure.1 A posterior bleb located completely under the upper lid reduces the risk of leak and infection, prevents cystic bleb formation and improves patient comfort.2 Recent studies have investigated methods to deliver large-area antimetabolite treatment in a safe and reliable way.3 A common technique of applying antimetabolite to Tenon’s capsule and sclera uses Moorfield forceps to introduce mitomycin C-soaked sponges into the dissected subconjunctival space. The grooved tips on the Moorfields forceps often become caught and preclude accurate positioning of the sponges. We have developed a method for effective antimetabolite application using sponges secured with a nylon suture4 and Monarch lens loading forceps (Alcon/Grieshaber, Fort Worth, TX, USA). In our trabeculectomy technique, a fornix-based conjunctival flap is dissected and a half-thickness scleral flap is cut. The antimetabolite is applied after creating the scleral flap and before entering the eye. Mitomycin C is applied at concentrations between 0.02% and 0.04% on five 5 × 8 mm microsurgical sponges, each secured with a single 6-0 silk suture as per a previously published method.4 Monarch lens loading forceps are used to easily and accurately place the sponges into the posterior superotemporal and superonasal subconjunctival space. We aim to treat a large area, as posterior as possible, including under the scleral flap. After a treatment time of 3 min, the sponges are removed with the Monarch forceps, and the scleral surface and conjunctiva are extensively rinsed with balanced salt solution (Alcon). This modification of a standard trabeculectomy technique2 is simple and uses inexpensive and readily available equipment. The use of Monarch forceps allows accurate insertion of antimetabolite-soaked sponges into the posterior subconjunctival space to achieve a large treatment area. The smooth forcep tips mean the sponges are released easily into their desired location and they are removed quickly by grasping the attached sutures, avoiding inconsistencies in duration of drug delivery. Inadvertent exposure of the cut edge of the conjunctiva to antimetabolite from anteriorly placed sponges is also able
to be avoided, decreasing the risk of wound leak and dehiscence.2
Kate Leahy BMed,1 Wendy Whittles RN2 and Andrew White PhD FRANZCO1,2,3,4 1 Westmead Hospital, Westmead, 2Parramatta Eye Hospital, Parramatta, 3Centre for Vision Research, Westmead Millennium Institute, and 4Save Sight Institute, University of Sydney, Sydney, New South Wales, Australia Received 1 March 2014; accepted 8 March 2014.
REFERENCES 1. Önol M, Aktas¸ Z, Hasanreisog˘lu B. Enhancement of the success rate in trabeculectomy: large-area mitomycin-C application. Clin Experiment Ophthalmol 2008; 36: 316–22. 2. Khaw P, Dahlmann-Noor A, Mireskandari K. Trabeculectomy technique. Glaucoma Today 2005; 3: 22–9. 3. Healey P, Crowston J. Trypan blue identifies antimetabolite treatment area in trabeculectomy. Br J Ophthalmol 2005; 89: 1152–6. 4. Knape RM, Smith MF. Antimetabolite application technique in trabeculectomy surgery. Clin Experiment Ophthalmol 2011; 39: 580–1.
Primary selective laser trabeculoplasty: a cautionary tale Selective laser trabeculoplasty (SLT) is an established treatment for ocular hypertension (OHT) or open-angle glaucoma as it produces a clinically meaningful intraocular pressure (IOP) reduction with a favourable safety profile. There is an increasing trend to offer SLT as primary therapy; this is supported by clinical trial data showing prostaglandin monotherapy and SLT have equal efficacy.1 However, we would like to draw attention to an important aspect of patient management when administering SLT as primary therapy for glaucoma. A 59-year-old male with a known history of OHT (baseline IOP right [R] 25 mmHg, left [L] 19 mmHg; central corneal thickness R 488 μm, L 506 μm; cup-to-disc ratio [CDR] R and L 0.6; full field on automated perimetry; normal retinal nerve fibre layer optical coherence tomography [OCT]) was offered right SLT as an alternative to latanoprost monotherapy which had been trialled without success. A right SLT was performed (0.4–0.6 mJ × 360 degrees) with IOP reducing to 21 mmHg post-SLT.
Competing/conflicts of interest: No stated conflict of interest. Funding sources: No stated funding sources. Competing/conflicts of interest: No stated conflict of interest. Funding sources: No stated funding sources. © 2014 Royal Australian and New Zealand College of Ophthalmologists
884
Letters to the Editor
(a)
(b)
30
(c)
30
(d)
The patient was lost to follow up for four years until he was urgently referred back by his optometrist. Repeat examination revealed IOPs of R 24 mmHg and L 18 mmHg with glaucomatous optic neuropathy (CDR R 0.8 and L 0.6) (Fig. 1d). OCT demonstrated retinal nerve fibre layer thinning bilaterally and automated perimetry showed a right superior arcuate defect (Fig. 1b). He had not seen another ophthalmologist in the four years since last review and was not taking topical antihypertensive therapy. The patient informed us that since his IOP had fallen with SLT treatment, he felt he did not need further treatment or review. This case highlights the risk that primary SLT is perceived by some patients to be a definitive or curative treatment. Without the need to regularly use glaucoma eye drops, patients may forget the potential threat of glaucoma and/or underestimate the need for regular surveillance and further intervention. Our patient felt the SLT had cured his OHT; he was not aware of the diminishing effect of SLT over time and the importance of long-term monitoring for glaucoma development. Regular review could have prevented glaucoma onset or identified its development at an earlier stage in this case. Prospective studies of the long-term effects of SLT demonstrate that its IOP-lowering effect falls over time. Bovell et al.2 published a long-term evaluation of participants from an original 12-month duration randomized controlled trial. The percentage of patients at one year maintaining a 20% IOP reduction (without supplementary medical, surgical or laser intervention) was approximately 60%, at two years it was 50%, and by five years this had fallen to 25%. There has been a rapid uptake of SLT amongst ophthalmologists3,4 based on many factors including the potential to circumvent the issue of patient non-adherence associated with topical antihypertensive therapy. However, as our case
Figure 1. Humphrey Visual Field grey scale and red-free fundus photographs of the right eye. Compared to the normal field at the time of SLT (a), there is a nasal step and superior partial arcuate defect at follow up four years later (b). Comparison of red-free fundus photographs at the time of SLT (c) and four years later (d) shows enlargement of the cup-to-disc ratio, loss of neuroretinal rim and an inferotemporal retinal nerve fibre layer defect (arrows) at follow up.
demonstrates, these benefits may be offset by nonattendance at review because of a false impression that treatment is curative. To address this problem, it is important that ophthalmologists include in their consent a discussion about the importance of long-term follow up of patients. This should include emphasis on the variable duration of treatment effect of SLT in some patients, and the potential need for repeat procedures or additional therapy.
Shweta Kaushik BMed PhD,1 Ross Ferrier FRANZCO2 and Colin Clement PhD FRANZCO2,3 1 Glaucoma Unit, Westmead Hospital, Sydney, 2Wyong Eye Surgery, Wyong, New South Wales, and 3Glaucoma Unit, Sydney Eye Hospital, Sydney, Australia Received 6 March 2014; accepted 13 March 2014.
REFERENCES 1. Katz LJ, Steinmann WC, Kabir A et al. Selective laser trabeculoplasty versus medical therapy as initial treatment of glaucoma: a prospective, randomized trial. J Glaucoma 2012; 21; 460–8. 2. Bovell AM, Damji KF, Hodge WG, Rock WJ, Buhrman RR, Pan YI. Long term effects on the lowering of intraocular pressure: selective laser or argon laser trabeculoplasty? Can J Ophthalmol 2011; 46: 408–13. 3. Ramulu PY, Corcoran KJ, Corcoran SL, Robin AL. Utilization of various glaucoma surgeries and procedures in Medicare beneficiaries from 1995 to 2004. Ophthalmology 2007; 114: 2265–70. 4. Rachmiel R, Trope GE, Chipman ML, Gouws P, Buys YM. Laser trabeculoplasty trends with the introduction of new medical treatments and selective laser trabeculoplasty. J Glaucoma 2006; 15: 306–9.
© 2014 Royal Australian and New Zealand College of Ophthalmologists
Copyright of Clinical & Experimental Ophthalmology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
