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or reading glasses would be better options and should be discussed in detail with the patient. Eric D. Donnenfeld, MD Rockville Centre, New York, USA Valerie Trubnik, MD Mineola, New York, USA Dr. Donnenfeld is a consultant to Abbott Medical Optics, Alcon, Bausch & Lomb, and Glaukos.
- The management of cataracts and glaucoma is a common occurrence in an aging population. This patient has cataracts that affect his activities of daily living. Namely, he is having difficulty driving at night because of glare disability. I am concerned about his visual field loss progression in the recent past, despite the fact that his visual field examinations have been relatively stable over the past 1 to 2 years. However, given the amount of optic nerve damage and corresponding visual field loss, the current IOP level is too high in both eyes, despite maximum tolerated medical therapy. In evaluating this patient for surgery, I would discuss 3 options for both eyes: (1) cataract surgery alone; (2) combined cataract surgery and MIGS with microbypass stent implantation; (3) combined cataract surgery and glaucoma filtering surgery, such as trabeculectomy with placement of a miniature glaucoma shunt. In regard to cataract surgery alone, the literature supports that mild IOP lowering can be achieved with cataract surgery alone. Most patients continue to require glaucoma medical therapy, however. Combining microbypass stent implantation at the same time as cataract surgery is more likely to lead to reasonable IOP control with less need for glaucoma medications in patients with mild to moderate POAG. Glaucoma filtering procedures are more likely to achieve low IOP targets when combined with cataract surgery. I would recommend this patient have cataract surgery combined with trabeculectomy and placement of a miniature shunt in the left eye first. This would be followed by combined cataract surgery and microbypass stent implantation to the right eye after the left eye has recovered from surgery (typically 4 to 6 weeks). I do not think a multifocal IOL will be in the patient's best interest because of concerns about the potential further loss of contrast sensitivity. I would recommend a monofocal approach; I would tell the patient that such an approach would lead to a good prognosis for excellent distance visual acuity but that he will, at a minimum, require reading glasses after surgery. I would also caution him that he will not notice
243
improvement in the central visual field loss in the left eye. The surgery in the left eye would be performed at 2 sites. The phacoemulsification and IOL placement would be performed using a temporal clear corneal approach. This would be followed by trabeculectomy in the superonasal quadrant. The approach to surgery in the right eye will also be through a temporal clear corneal approach. The microbypass stent would be implanted first; this would be followed by phacoemulsification with IOL placement. By combining the glaucoma and cataract procedures as mentioned, the patient is more likely to achieve quick visual recovery and more independence from glaucoma medications. Leon Herndon, MD Durham, North Carolina, USA
- This patient has moderate to advanced cupping of both optic nerves with more severe disease in the left eye, as seen by significant defects in the superior and inferior visual fields. Triple medical therapy, essentially maximum medical therapy in my practice, has lowered the IOP to a degree that allowed for stable disease over the past 1 to 2 years. The presence of visually significant cataracts now allows an opportunity to improve vision and decrease dependence on topical medications. The patient desires best-corrected vision for distance; thus, a monofocal 1-piece acrylic IOL would be my choice. A toric IOL would have been an option if significant astigmatism were present in either eye. I would counsel the patient against multifocal IOLs, despite his desire for spectacle independence, because this would further compromise contrast sensitivity issues associated with his advanced glaucoma. The desire for improved night vision would also argue against multifocal IOL implantation. The decision regarding a glaucoma intervention requires more thought. The right eye has superior visual field depression with an IOP in the high teens. Cataract extraction alone will likely decrease IOP by 1 to 3 mm Hg and might allow a decrease in medication by 1 drop. Simultaneous implantation of a microbypass stent is an option in this patient with open angles and would increase the likelihood of sustained IOP reduction and a reduction in medications. Given that adverse events associated with microbypass stent implantation are unlikely and of minimal consequence, I would recommend this option for the right eye. I would inject carbachol at the end of the case for IOP control in the immediate postoperative period and to minimize the chance of a
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significant IOP spike. Endocyclophotocoagulation combined with cataract extraction is another option depending on availability and surgeon experience; however, endocyclophotocoagulation is more invasive and is more likely to cause postoperative IOP spikes. Management of the left eye, in which the disease is more advanced, is not as straightforward. The options are cataract extraction with trabeculectomy (staged or combined according to physician experience and preference) versus cataract extraction with microbypass stent implantation or endocyclophotocoagulation as a first step before more invasive surgery. Given that the left eye has been stable for 2 years and the visual field defects likely occurred at higher IOP levels (max 31 mm Hg), I believe a less invasive approach, such as combined cataract extraction–endocyclophotocoagulation, would be appropriate. I have observed lower IOPs after endocyclophotocoagulation than after microbypass stent implantation combined with cataract extraction, and this directs my choice. I would again use carbachol at the end of the procedure and prescribe oral acetazolamide for additional IOP control. I would examine the patient a few hours after surgery to check IOP and address any elevation. This patient should be counseled preoperatively about the potential need for trabeculectomy if IOP control were compromised after cataract extraction–endocyclophotocoagulation and that decreasing medications might not be possible depending on the IOP response. The patient would then have the choice to have trabeculectomy or glaucoma drainage device placement in the future because cataract extraction–endocyclophotocoagulation would not compromise these options. My goal is to offer optimum vision correction while reducing dependence on topical therapy. I believe the approach of cataract surgery and MIGS can achieve this goal in both eyes. Malik Y. Kahook, MD Aurora, Colorado, USA
- This patient has advanced glaucomatous cupping and field loss. In addition, his vision is compromised by cataracts. Details about the extent of his corneal astigmatism, axial length, zonular support, pupil dilation, and macular appearance are not provided. A discussion is necessary to determine his visual needs and goals and how best to manage the IOP in the immediate postoperative period as well as over the long term. I would discourage the use of a multifocal IOL because it would further degrade the quality of vision. A better option if the patient seeks to be less
dependent on glasses would be monovision, depending on his needs and previous experience. If low levels of corneal astigmatism were present, arcuate incisions created with a femtosecond laser could be considered. A toric IOL is a very effective option in eyes with a higher level of astigmatism. Unlike the multifocal IOL, the toric IOL does not degrade light. The options for managing glaucoma in the presence of cataract surgery have been enhanced over the past few years. Although cataract removal alone may provide IOP control, I do not believe it will be sufficient given the severity of this patient's glaucoma. We would discuss the currently available options for a combined cataract–glaucoma procedure. Safety is my biggest concern with combined procedures because I do not want to jeopardize the anticipated return of excellent acuity. Trabeculectomy has too many early and late complications for this initial procedure. I would consider trabeculectomy with mitomycin-C (MMC) as my second procedure if the IOP were not well controlled after the combined procedure. The category of MIGS devices, on the other hand, is more appealing given their safety and efficacy. At this time, I would recommend managing the glaucoma via a combined procedure, placing 1 or 2 microbypass stents (approximately 30 degrees apart) in the canal of Schlemm as close as possible to the collector system at the conclusion of cataract surgery. Richard A. Lewis, MD Sacramento, California, USA
- Given the level of IOP on 3 medications and evidence of ongoing progression, my primary concern for this patient is that the IOP is not controlled. I would set a target in the mid-teens for the right eye and low teens for the left. Performing cataract surgery provides an opportunity for both eyes to have a concomitant IOP-lowering procedure to achieve this goal. My surgical approach would be phacotrabeculectomy with MMC in the left eye and phacoemulsification with microbypass stent implantation in the left eye. The severe glaucoma damage in the left eye demands definitive IOP-lowering filtration surgery to prevent ongoing progression The right eye might achieve the target IOP with MIGS along with continuation of some or all the glaucoma medications but could have trabeculectomy later if necessary. My discussion with this moderately myopic patient regarding postoperative refractive results would begin with a conversation about whether he currently reads without glasses. If so, I would explain that correcting to emmetropia with a monofocal IOL
J CATARACT REFRACT SURG - VOL 41, JANUARY 2015
or reading glasses would be better options and should be discussed in detail with the patient. Eric D. Donnenfeld, MD Rockville Centre, New York, USA Valerie Trubnik, MD Mineola, New York, USA Dr. Donnenfeld is a consultant to Abbott Medical Optics, Alcon, Bausch & Lomb, and Glaukos.
- The management of cataracts and glaucoma is a common occurrence in an aging population. This patient has cataracts that affect his activities of daily living. Namely, he is having difficulty driving at night because of glare disability. I am concerned about his visual field loss progression in the recent past, despite the fact that his visual field examinations have been relatively stable over the past 1 to 2 years. However, given the amount of optic nerve damage and corresponding visual field loss, the current IOP level is too high in both eyes, despite maximum tolerated medical therapy. In evaluating this patient for surgery, I would discuss 3 options for both eyes: (1) cataract surgery alone; (2) combined cataract surgery and MIGS with microbypass stent implantation; (3) combined cataract surgery and glaucoma filtering surgery, such as trabeculectomy with placement of a miniature glaucoma shunt. In regard to cataract surgery alone, the literature supports that mild IOP lowering can be achieved with cataract surgery alone. Most patients continue to require glaucoma medical therapy, however. Combining microbypass stent implantation at the same time as cataract surgery is more likely to lead to reasonable IOP control with less need for glaucoma medications in patients with mild to moderate POAG. Glaucoma filtering procedures are more likely to achieve low IOP targets when combined with cataract surgery. I would recommend this patient have cataract surgery combined with trabeculectomy and placement of a miniature shunt in the left eye first. This would be followed by combined cataract surgery and microbypass stent implantation to the right eye after the left eye has recovered from surgery (typically 4 to 6 weeks). I do not think a multifocal IOL will be in the patient's best interest because of concerns about the potential further loss of contrast sensitivity. I would recommend a monofocal approach; I would tell the patient that such an approach would lead to a good prognosis for excellent distance visual acuity but that he will, at a minimum, require reading glasses after surgery. I would also caution him that he will not notice
243
improvement in the central visual field loss in the left eye. The surgery in the left eye would be performed at 2 sites. The phacoemulsification and IOL placement would be performed using a temporal clear corneal approach. This would be followed by trabeculectomy in the superonasal quadrant. The approach to surgery in the right eye will also be through a temporal clear corneal approach. The microbypass stent would be implanted first; this would be followed by phacoemulsification with IOL placement. By combining the glaucoma and cataract procedures as mentioned, the patient is more likely to achieve quick visual recovery and more independence from glaucoma medications. Leon Herndon, MD Durham, North Carolina, USA
- This patient has moderate to advanced cupping of both optic nerves with more severe disease in the left eye, as seen by significant defects in the superior and inferior visual fields. Triple medical therapy, essentially maximum medical therapy in my practice, has lowered the IOP to a degree that allowed for stable disease over the past 1 to 2 years. The presence of visually significant cataracts now allows an opportunity to improve vision and decrease dependence on topical medications. The patient desires best-corrected vision for distance; thus, a monofocal 1-piece acrylic IOL would be my choice. A toric IOL would have been an option if significant astigmatism were present in either eye. I would counsel the patient against multifocal IOLs, despite his desire for spectacle independence, because this would further compromise contrast sensitivity issues associated with his advanced glaucoma. The desire for improved night vision would also argue against multifocal IOL implantation. The decision regarding a glaucoma intervention requires more thought. The right eye has superior visual field depression with an IOP in the high teens. Cataract extraction alone will likely decrease IOP by 1 to 3 mm Hg and might allow a decrease in medication by 1 drop. Simultaneous implantation of a microbypass stent is an option in this patient with open angles and would increase the likelihood of sustained IOP reduction and a reduction in medications. Given that adverse events associated with microbypass stent implantation are unlikely and of minimal consequence, I would recommend this option for the right eye. I would inject carbachol at the end of the case for IOP control in the immediate postoperative period and to minimize the chance of a
J CATARACT REFRACT SURG - VOL 41, JANUARY 2015
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CONSULTATION SECTION
significant IOP spike. Endocyclophotocoagulation combined with cataract extraction is another option depending on availability and surgeon experience; however, endocyclophotocoagulation is more invasive and is more likely to cause postoperative IOP spikes. Management of the left eye, in which the disease is more advanced, is not as straightforward. The options are cataract extraction with trabeculectomy (staged or combined according to physician experience and preference) versus cataract extraction with microbypass stent implantation or endocyclophotocoagulation as a first step before more invasive surgery. Given that the left eye has been stable for 2 years and the visual field defects likely occurred at higher IOP levels (max 31 mm Hg), I believe a less invasive approach, such as combined cataract extraction–endocyclophotocoagulation, would be appropriate. I have observed lower IOPs after endocyclophotocoagulation than after microbypass stent implantation combined with cataract extraction, and this directs my choice. I would again use carbachol at the end of the procedure and prescribe oral acetazolamide for additional IOP control. I would examine the patient a few hours after surgery to check IOP and address any elevation. This patient should be counseled preoperatively about the potential need for trabeculectomy if IOP control were compromised after cataract extraction–endocyclophotocoagulation and that decreasing medications might not be possible depending on the IOP response. The patient would then have the choice to have trabeculectomy or glaucoma drainage device placement in the future because cataract extraction–endocyclophotocoagulation would not compromise these options. My goal is to offer optimum vision correction while reducing dependence on topical therapy. I believe the approach of cataract surgery and MIGS can achieve this goal in both eyes. Malik Y. Kahook, MD Aurora, Colorado, USA
- This patient has advanced glaucomatous cupping and field loss. In addition, his vision is compromised by cataracts. Details about the extent of his corneal astigmatism, axial length, zonular support, pupil dilation, and macular appearance are not provided. A discussion is necessary to determine his visual needs and goals and how best to manage the IOP in the immediate postoperative period as well as over the long term. I would discourage the use of a multifocal IOL because it would further degrade the quality of vision. A better option if the patient seeks to be less
dependent on glasses would be monovision, depending on his needs and previous experience. If low levels of corneal astigmatism were present, arcuate incisions created with a femtosecond laser could be considered. A toric IOL is a very effective option in eyes with a higher level of astigmatism. Unlike the multifocal IOL, the toric IOL does not degrade light. The options for managing glaucoma in the presence of cataract surgery have been enhanced over the past few years. Although cataract removal alone may provide IOP control, I do not believe it will be sufficient given the severity of this patient's glaucoma. We would discuss the currently available options for a combined cataract–glaucoma procedure. Safety is my biggest concern with combined procedures because I do not want to jeopardize the anticipated return of excellent acuity. Trabeculectomy has too many early and late complications for this initial procedure. I would consider trabeculectomy with mitomycin-C (MMC) as my second procedure if the IOP were not well controlled after the combined procedure. The category of MIGS devices, on the other hand, is more appealing given their safety and efficacy. At this time, I would recommend managing the glaucoma via a combined procedure, placing 1 or 2 microbypass stents (approximately 30 degrees apart) in the canal of Schlemm as close as possible to the collector system at the conclusion of cataract surgery. Richard A. Lewis, MD Sacramento, California, USA
- Given the level of IOP on 3 medications and evidence of ongoing progression, my primary concern for this patient is that the IOP is not controlled. I would set a target in the mid-teens for the right eye and low teens for the left. Performing cataract surgery provides an opportunity for both eyes to have a concomitant IOP-lowering procedure to achieve this goal. My surgical approach would be phacotrabeculectomy with MMC in the left eye and phacoemulsification with microbypass stent implantation in the left eye. The severe glaucoma damage in the left eye demands definitive IOP-lowering filtration surgery to prevent ongoing progression The right eye might achieve the target IOP with MIGS along with continuation of some or all the glaucoma medications but could have trabeculectomy later if necessary. My discussion with this moderately myopic patient regarding postoperative refractive results would begin with a conversation about whether he currently reads without glasses. If so, I would explain that correcting to emmetropia with a monofocal IOL
J CATARACT REFRACT SURG - VOL 41, JANUARY 2015
