- Email: [email protected]
November consultation #6
CONSULTATION SECTION
- Treating this very challenging case should include reducing the photophobia with iridodialysis repair and restoring good visual acuity. It seems possible to safely manage the eye through a modern small-incision surgery approach. The crystalline lens can be managed by a small-incision technique considering the arc length of the zonular defect. Depending on the surgical findings, the capsular bag might have to be fixated to the scleral wall using a modified CTR or CTS with fixation elements to the scleral wall. The pupil should be fully dilated for surgery. Ideally, anterior vitrectomy without infusion would be performed after injection of triamcinolone to allow visualization of the vitreous in the area of the iridodialysis. At this step, the placement of 2 iris retractors on the pupillary margin of the displaced iris would provide good exposure of the lens. The capsulorhexis would be centered on the lens. During or at the end of opening the capsule, a capsule hook would be placed in front of the zonular defect to stabilize the capsular bag and secure further maneuvers. Viscodissection would separate the cortical material from the capsule fornix before CTR implantation. There are 2 options at this step depending on whether the capsular bag will be fixated to the scleral wall. A simple CTR should be sufficient based on the arc length of the zonular defect (approximately 3 clock hours [25%]). If the zonular defect appears to be longer, a Cionni modified CTR would be fixated to the scleral wall. The ring would be inserted under attentive observation and control of the stress placed on the zonular fibers. At the end of this maneuver, the capsule retractor hook would be removed. A chop technique in which a central groove is created while stress on the zonular fibers is minimized would be the best option for lens removal. The cortex removal must be performed with low aspiration or with a cortex cannula to avoid traction on the capsular bag, especially in the area of the zonular defect. Careful complete lens epithelial cell aspiration from the anterior capsule leaf is an important step to reduce secondary fibrotic changes. A single-piece hydrophobic IOL would be primarily implanted in the anterior chamber, after which the haptics would be carefully maneuvered into the bag to minimize traction on the zonular fibers. Injection of triamcinolone at this step should ensure the absence of vitreous. The pupil would then be constricted and the iris prepared under OVD for suturing. A scleral flap starting 2.0 mm back from the limbus would be dissected, extending over 3 clock hours. A 10-0 polypropylene suture double-armed with straight or curved 13.0 mm needles would be used to repair the iridodialysis. Two fixation points
1933
would be necessary. Entry through the main incision using a curved needle would allow comfortable suturing under the scleral flap. At the end of the procedure, the conjunctiva could be sutured or glued. Dominique Pietrini, MD Paris, France
- This patient presents with 2 major problems; that is, photophobia and poor visual acuity in an eye that sustained blunt trauma in his late childhood. Due to good vision in his early childhood and the normal retinal and macular appearance, the potential for visual acuity restoration is good. Comparison of the axial length (AL) between the eyes will add another clue regarding the visual potential of the eye. Both problems can be addressed in the same surgery. The first step would be an intense discussion with the patient so he will have realistic expectations regarding the surgery results. Topical nonsteroidal antiinflammatory drug (NSAID) drops 3 days before surgery would be prescribed. The first step of the surgery would be to push the prolapsed vitreous posteriorly using a dispersive OVD. If this were not possible, a limited anterior vitrectomy would be performed using triamcinolone to stain the vitreous. Next, the iridodialysis would be assessed to determine whether it would interfere with the cataract extraction to follow. If so, at this point, it would be fixated in a scleral pocket with 10-0 polypropylene sutures using Richard Hoffman’s technique for fixation of subluxated IOLs. The next step would be to address the advanced cataract. With a stable capsular bag and limited segmental zonular defect, a segmental capsular stabilization device should be available. It is recommended to use the device as late as possible but as early as needed to stabilize the area of the missing zonular fibers. Due to the advanced cataract, dye may be required for capsule staining. A soft-shell technique using a combination of dispersive OVD and cohesive OVD is recommended for corneal endothelial cell protection, and a phacoemulsification technique that will minimize the use of the ultrasound (US) energy and zonular damage should be used. My preferred technique would be vertical chopping. Intraocular lens selection would be dependent on the posterior corneal astigmatism. Because the posterior astigmatism is negative with high with-the-rule (WTR) posterior corneal astigmatism, it may be sufficient to plan the surgical incision at 90 degrees; with low WTR posterior corneal astigmatism or against-the-rule posterior corneal astigmatism, a toric IOL may be considered.
J CATARACT REFRACT SURG - VOL 40, NOVEMBER 2014
1934
CONSULTATION SECTION
If measurement of the posterior astigmatism is not possible, I would use the Baylor nomogram1 or the new Barrett calculator available at the American Society of Cataract and Refractive Surgery web site.A If the surgery can be completed without fixation of the iridodialysis, it would be the time to close it as detailed above. Anterior vitrectomy, if necessary, should be completed at this time. Postoperatively the patient would be treated with antibiotic and steroid topical drops, similar to regular cataract extraction surgery. However, NSAID topical drops would also be prescribed for an extended period (approximately 2 months). Guy Kleinmann, MD Rehovot, Israel
REFERENCE 1. Koch DD, Jenkins RB, Weikert MP, Yeu E, Wang L. Correcting astigmatism with toric intraocular lenses: effect of posterior corneal astigmatism. J Cataract Refract Surg 2013; 39:1803– 1809
OTHER CITED MATERIAL A. Barrett toric calculator. Available at: http://www.ascrs.org/barretttoric-calculator. Accessed September 3, 2014
- This case in which the patient’s main complaint is photophobia in the right eye requires consideration of several issues; that is, the hard cataract, temporal iridodialysis, and zonular dehiscence with localized vitreous prolapse. It seems as though the lens is not wobbling, and the normal ECC is reassuring. The first question is whether and how to extract the dense cataract considering that the pupil does not dilate well and there is vitreous prolapse. In cases like this, it is advantageous to have several optional plans. I would start by preparing a sclerocorneal tunnel superiorly away from the iridodialysis that can easily be enlarged if conversion to an extracapsular cataract extraction (ECCE) becomes necessary. The use of trypan blue to stain the anterior capsule and of a dispersive OVD to protect the endothelium seems necessary, as does the additional use of a cohesive OVD to slightly push back and block the vitreous prolapse. Although nowadays I prefer a Malyugin ring, an iris retractor from the temporal side should be used for enlargement of the pupil in this case. The retractor could also be used later to suspend the temporal capsulotomy to stabilize the lens during phacoemulsification and irrigation/aspiration. Additional retractors might be necessary to further enlarge the pupil (eg, when converting to ECCE). A regular-sized
curvilinear capsulorhexis of the trypan blue–stained capsule should be feasible. Care should be taken during hydrodissection not to overfill the anterior chamber and luxate the lens. For phacoemulsification, I would use a horizontal chop technique with the Lieberman microfinger to lift the entire lens from the posterior capsule and stabilize the nucleus during phacoemulsification with the aim of not straining the remaining zonular fibers. This is initially performed with a high vacuum setting (400 mm Hg venturi pump) and relatively low pressure (bottle height 85 cm) while the lens behavior, particularly on the temporal side, is observed. Initially, the US energy should be set at approximately 50% in the burst mode to reduce the total amount of power delivered. With the use of the microfinger/chopper, the nucleus can be stabilized and rotated. After the nucleus is chopped in little segments over 360 degrees (care should be taken not to injure the capsule with sharp nucleus fragments), I would switch to pulse to remove the chopped segments. I would implant a regular CTR before placing the IOL in the bag. Should more pronounced subluxation of the lens become evident during surgery, a Cionni ring with a suspension eyelet could be used alternatively. I would not expect the vitreous to cause too much trouble; however, if it did, careful anterior vitrectomy could be necessary at any stage during surgery. Because the patient’s main complaint is photophobia, the last question would be how to address the temporal iridodialysis. I would try to refixate the iris transsclerally. Alternatively, McCannel–Siepser knots could be placed to reduce the pseudopupil. Or, a cut-to-size segment of an artificial silicone iris could be implanted later after a trial of iris-printed contact lenses if the patient still reports photophobia. David Goldblum, MD Basel, Switzerland
- The patient’s eye was injured at the age of 12 years, which means the eye might have become amblyopic. Furthermore, the patient might have lost stereopsis. It is surprising that the glare is worse now than the year before. The temporal iridodialysis might explain these symptoms, although the glare has been present since the injury occurred. The case description says this may be due to the progressive shrinkage of the lens and the consecutive extension of the coloboma.
J CATARACT REFRACT SURG - VOL 40, NOVEMBER 2014
- Treating this very challenging case should include reducing the photophobia with iridodialysis repair and restoring good visual acuity. It seems possible to safely manage the eye through a modern small-incision surgery approach. The crystalline lens can be managed by a small-incision technique considering the arc length of the zonular defect. Depending on the surgical findings, the capsular bag might have to be fixated to the scleral wall using a modified CTR or CTS with fixation elements to the scleral wall. The pupil should be fully dilated for surgery. Ideally, anterior vitrectomy without infusion would be performed after injection of triamcinolone to allow visualization of the vitreous in the area of the iridodialysis. At this step, the placement of 2 iris retractors on the pupillary margin of the displaced iris would provide good exposure of the lens. The capsulorhexis would be centered on the lens. During or at the end of opening the capsule, a capsule hook would be placed in front of the zonular defect to stabilize the capsular bag and secure further maneuvers. Viscodissection would separate the cortical material from the capsule fornix before CTR implantation. There are 2 options at this step depending on whether the capsular bag will be fixated to the scleral wall. A simple CTR should be sufficient based on the arc length of the zonular defect (approximately 3 clock hours [25%]). If the zonular defect appears to be longer, a Cionni modified CTR would be fixated to the scleral wall. The ring would be inserted under attentive observation and control of the stress placed on the zonular fibers. At the end of this maneuver, the capsule retractor hook would be removed. A chop technique in which a central groove is created while stress on the zonular fibers is minimized would be the best option for lens removal. The cortex removal must be performed with low aspiration or with a cortex cannula to avoid traction on the capsular bag, especially in the area of the zonular defect. Careful complete lens epithelial cell aspiration from the anterior capsule leaf is an important step to reduce secondary fibrotic changes. A single-piece hydrophobic IOL would be primarily implanted in the anterior chamber, after which the haptics would be carefully maneuvered into the bag to minimize traction on the zonular fibers. Injection of triamcinolone at this step should ensure the absence of vitreous. The pupil would then be constricted and the iris prepared under OVD for suturing. A scleral flap starting 2.0 mm back from the limbus would be dissected, extending over 3 clock hours. A 10-0 polypropylene suture double-armed with straight or curved 13.0 mm needles would be used to repair the iridodialysis. Two fixation points
1933
would be necessary. Entry through the main incision using a curved needle would allow comfortable suturing under the scleral flap. At the end of the procedure, the conjunctiva could be sutured or glued. Dominique Pietrini, MD Paris, France
- This patient presents with 2 major problems; that is, photophobia and poor visual acuity in an eye that sustained blunt trauma in his late childhood. Due to good vision in his early childhood and the normal retinal and macular appearance, the potential for visual acuity restoration is good. Comparison of the axial length (AL) between the eyes will add another clue regarding the visual potential of the eye. Both problems can be addressed in the same surgery. The first step would be an intense discussion with the patient so he will have realistic expectations regarding the surgery results. Topical nonsteroidal antiinflammatory drug (NSAID) drops 3 days before surgery would be prescribed. The first step of the surgery would be to push the prolapsed vitreous posteriorly using a dispersive OVD. If this were not possible, a limited anterior vitrectomy would be performed using triamcinolone to stain the vitreous. Next, the iridodialysis would be assessed to determine whether it would interfere with the cataract extraction to follow. If so, at this point, it would be fixated in a scleral pocket with 10-0 polypropylene sutures using Richard Hoffman’s technique for fixation of subluxated IOLs. The next step would be to address the advanced cataract. With a stable capsular bag and limited segmental zonular defect, a segmental capsular stabilization device should be available. It is recommended to use the device as late as possible but as early as needed to stabilize the area of the missing zonular fibers. Due to the advanced cataract, dye may be required for capsule staining. A soft-shell technique using a combination of dispersive OVD and cohesive OVD is recommended for corneal endothelial cell protection, and a phacoemulsification technique that will minimize the use of the ultrasound (US) energy and zonular damage should be used. My preferred technique would be vertical chopping. Intraocular lens selection would be dependent on the posterior corneal astigmatism. Because the posterior astigmatism is negative with high with-the-rule (WTR) posterior corneal astigmatism, it may be sufficient to plan the surgical incision at 90 degrees; with low WTR posterior corneal astigmatism or against-the-rule posterior corneal astigmatism, a toric IOL may be considered.
J CATARACT REFRACT SURG - VOL 40, NOVEMBER 2014
1934
CONSULTATION SECTION
If measurement of the posterior astigmatism is not possible, I would use the Baylor nomogram1 or the new Barrett calculator available at the American Society of Cataract and Refractive Surgery web site.A If the surgery can be completed without fixation of the iridodialysis, it would be the time to close it as detailed above. Anterior vitrectomy, if necessary, should be completed at this time. Postoperatively the patient would be treated with antibiotic and steroid topical drops, similar to regular cataract extraction surgery. However, NSAID topical drops would also be prescribed for an extended period (approximately 2 months). Guy Kleinmann, MD Rehovot, Israel
REFERENCE 1. Koch DD, Jenkins RB, Weikert MP, Yeu E, Wang L. Correcting astigmatism with toric intraocular lenses: effect of posterior corneal astigmatism. J Cataract Refract Surg 2013; 39:1803– 1809
OTHER CITED MATERIAL A. Barrett toric calculator. Available at: http://www.ascrs.org/barretttoric-calculator. Accessed September 3, 2014
- This case in which the patient’s main complaint is photophobia in the right eye requires consideration of several issues; that is, the hard cataract, temporal iridodialysis, and zonular dehiscence with localized vitreous prolapse. It seems as though the lens is not wobbling, and the normal ECC is reassuring. The first question is whether and how to extract the dense cataract considering that the pupil does not dilate well and there is vitreous prolapse. In cases like this, it is advantageous to have several optional plans. I would start by preparing a sclerocorneal tunnel superiorly away from the iridodialysis that can easily be enlarged if conversion to an extracapsular cataract extraction (ECCE) becomes necessary. The use of trypan blue to stain the anterior capsule and of a dispersive OVD to protect the endothelium seems necessary, as does the additional use of a cohesive OVD to slightly push back and block the vitreous prolapse. Although nowadays I prefer a Malyugin ring, an iris retractor from the temporal side should be used for enlargement of the pupil in this case. The retractor could also be used later to suspend the temporal capsulotomy to stabilize the lens during phacoemulsification and irrigation/aspiration. Additional retractors might be necessary to further enlarge the pupil (eg, when converting to ECCE). A regular-sized
curvilinear capsulorhexis of the trypan blue–stained capsule should be feasible. Care should be taken during hydrodissection not to overfill the anterior chamber and luxate the lens. For phacoemulsification, I would use a horizontal chop technique with the Lieberman microfinger to lift the entire lens from the posterior capsule and stabilize the nucleus during phacoemulsification with the aim of not straining the remaining zonular fibers. This is initially performed with a high vacuum setting (400 mm Hg venturi pump) and relatively low pressure (bottle height 85 cm) while the lens behavior, particularly on the temporal side, is observed. Initially, the US energy should be set at approximately 50% in the burst mode to reduce the total amount of power delivered. With the use of the microfinger/chopper, the nucleus can be stabilized and rotated. After the nucleus is chopped in little segments over 360 degrees (care should be taken not to injure the capsule with sharp nucleus fragments), I would switch to pulse to remove the chopped segments. I would implant a regular CTR before placing the IOL in the bag. Should more pronounced subluxation of the lens become evident during surgery, a Cionni ring with a suspension eyelet could be used alternatively. I would not expect the vitreous to cause too much trouble; however, if it did, careful anterior vitrectomy could be necessary at any stage during surgery. Because the patient’s main complaint is photophobia, the last question would be how to address the temporal iridodialysis. I would try to refixate the iris transsclerally. Alternatively, McCannel–Siepser knots could be placed to reduce the pseudopupil. Or, a cut-to-size segment of an artificial silicone iris could be implanted later after a trial of iris-printed contact lenses if the patient still reports photophobia. David Goldblum, MD Basel, Switzerland
- The patient’s eye was injured at the age of 12 years, which means the eye might have become amblyopic. Furthermore, the patient might have lost stereopsis. It is surprising that the glare is worse now than the year before. The temporal iridodialysis might explain these symptoms, although the glare has been present since the injury occurred. The case description says this may be due to the progressive shrinkage of the lens and the consecutive extension of the coloboma.
J CATARACT REFRACT SURG - VOL 40, NOVEMBER 2014