- Email: [email protected]
May consultation #5
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CONSULTATION SECTION
exacerbated by anterior shifting of the swollen crystalline lens. The OCT image shows that the crystalline lens pushes against almost the complete posterior side of the iris. Thus, neodymium:YAG (Nd:YAG) laser iridectomy might not be effective in restoring aqueous flow. In this case, performing prompt biometry and phacoemulsification is the best option for interrupting the pressure build-up cycle and the inevitable glaucomatous nerve damage and cataract progression. Also, the pressure should be controlled to reduce the risk for intraoperative subchoroidal bleeding. A capsulorhexis and standard phacoemulsification should be attempted. During capsulorhexis, the extent of zonular weakness can be estimated. If there is significant nuclear instability, the bag can be fixated using 2 to 4 disposable iris hooks. In case of zonular dehiscence of more than 4 clock hours, a capsular tension ring (CTR) with an eyelet for scleral fixation or a capsular anchor can be used.3,4 These devices can be fixated using a 10-0 polypropylene suture under a Hoffman scleral pocket.5 In case of subtotal zonular dehiscence, the bag should be removed after phacoemulsification, and then an anterior vitrectomy performed and an irisfixated IOL implanted. In a case involving persistent symptomatic (traumatic) mydriasis, either pilocarpine 0.125% or thymoxamine 0.5% could be prescribed.
and angle closure. Before surgery begins, the 40 mm Hg IOP must be lowered by dehydration of the vitreous. To achieve this, I would give 200 to 400 mL of mannitol 20% and 500 mg of acetazolamide 2 to 4 hours preoperatively. In most cases, this regimen lowers the IOP enough that the anterior chamber then can be deepened using an OVD. If the crystalline lens shows abnormal movability during capsulorhexis, I would use iris retractors to stabilize the capsular bag and perform a very gentle, low-flow phacoemulsification with thorough hydrodissection, hydrodelineation, and chopping of the nucleus and would use a dispersive OVD to prevent aspiration of the floppy capsule. If the zonular dehiscence does not allow the implantation of a stable, well-centered posterior chamber IOL (PC IOL), I would use a CTR and fixate it with 1 or 2 transscleral polypropylene sutures. Using a long needle, the capsular bag can be penetrated without the risk for a large capsule rupture. Alternatively, a Cionni ring with an eyelet designed for scleral suture fixation can be used. Keeping the capsular bag in place is preferable to removing it and implanting an angle-supported, irisfixated anterior chamber IOL (AC IOL). Should the patient need filtering surgery later, an intact capsule–IOL diaphragm would be very advantageous because it would safely prevent vitreous prolapse into the anterior chamber or filtering site.
Maurits V. Joosse, MD, PhD The Hague, the Netherlands
Andreas Forrer, MD Aarau, Switzerland
1. Wolter JR. Coup-contrecoup mechanism of ocular injuries. Am J Ophthalmol 1963; 56:785–796 2. Wong TY, Klein BEK, Klein R, Tomany SC. Relation of ocular trauma to cortical, nuclear, and posterior subcapsular cataract: the Beaver Dam Eye Study. Br J Ophthalmol 2002; 86:152– 155. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/ PMC1770991/pdf/bjo08600152.pdf. Accessed March 9, 2015 3. Cionni RJ, Osher RH. Management of profound zonular dialysis or weakness with a new endocapsular ring designed for scleral fixation. J Cataract Refract Surg 1998; 24:1299–1306 4. Assia EI, Ton Y, Michaeli A. Capsule anchor to manage subluxated lenses: initial clinical experience. J Cataract Refract Surg 2009; 35:1372–1379 5. Hoffman RS, Fine IH, Packer M. Rozenberg I: Scleral fixation using suture retrieval through a scleral tunnel. J Cataract Refract Surg 2006; 32:1259–1263. Available at: http://www.finemd.com/ reprints/Scleral%20Fixation%20Using%20suture%20Retrieval %20Through%20a%20Scleral%20Tu.pdf. Accessed March 9, 2015
- I would perform a gonioscopy to rule out angle closure not caused by pupillary block, which would not be relieved by an Nd:YAG laser iridotomy. If the gonioscopy shows an open angle, look for angle recession to anticipate late-onset postoperative glaucoma. A detailed indirect ophthalmoscopy should be done to rule out peripheral retinal tears. Anterior segment OCT (AS-OCT) should be performed focusing on the posterior capsule to exclude dehiscence in the posterior capsule, which could cause the nucleus to drop during hydrodissection or phacoemulsification. In a shallow anterior chamber caused by a swollen lens, phacodonesis might not be visible in spite of zonular weakness. The operating surgeon might encounter zonular weakness for the first time during capsulorhexis. In such a situation, the condition might require implantation of a CTR or another sutured capsule-support device. A zero aspheric monofocal IOL has better tolerance to decentration and is preferred over a negative aspheric IOL in eyes with zonular weakness. Multifocal and accommodating IOLs are best avoided in such eyes.
REFERENCES
- After a blunt trauma to the globe, the most probable etiology of this very shallow anterior chamber is an extensive lesion of the zonular fibers with an anteriorly displaced lens, causing a ciliovitreolenticular block
J CATARACT REFRACT SURG - VOL 41, MAY 2015
CONSULTATION SECTION
In an eye with a preexisting posterior capsule defect, one may have to resort to a 3-piece PC IOL fixated in the sulcus. In an eye with both zonular dialysis and a posterior capsule defect, an iris-fixated IOL that preferably is fixated to the backside of the iris or a scleral-fixated PC IOL might be the only choices. This patient's eye should be monitored postoperatively for glaucoma and peripheral retinal tears. Suhas Haldipurkar, MD Mumbai, India
- I am assuming that the scheduled surgery is exploratory to assess the extent of the damage, address the cataract and increased IOP, and resolve other issues that are encountered. There is pain with accommodation and the lens is mobile, with the anterior chamber becoming shallower as the lens moves forward when the patient is lying face-down. The lens itself is decentered, too. All these symptoms suggest zonular disruption. The flat anterior chamber includes iris and ciliary body damage and possible angle recession, which are very common findings after blunt trauma.1 The high IOP could have a number of causes, including phacomorphic glaucoma, angle recession, blockage of the trabecular meshwork by red blood cells, and angle closure. If the patient is of African descent, it would make sense to check for sickle cell disease because sickle cells do not pass as readily through the trabecular meshwork. This could explain the blood in the anterior chamber and the IOP remaining high 10 days after the injury. The blunt trauma was severe, and the cornea might have made contact with the natural lens when it was displaced posteriorly. An 8.0 mm posterior movement of the cornea reduces the anteroposterior measurement of the eye by 41% at the time of injury and allows the equatorial sclera to expand by 28%, causing massive traction at the vitreous base.2 Therefore, it is vital to follow up regarding vitreoretinal health. The key risks subsequently are glaucoma and retinal detachment. The contact between the corneal endothelium and the lens might lead to endothelial cell damage, and so doing an endothelial cell count (ECC) might be useful for tracking endothelial cell health. Performing gonioscopy would be important for diagnosing angle recession. Because there are anterior and posterior capsule and subcapsular changes, the surgery would likely be cataract surgery. Replacing the thick crystalline lens (normally approximately 4.5 mm thick at this age) with an IOL (typically less than 1.0 mm thick) would largely decongest the anterior chamber and resolve the
1117
phacomorphic and angle-closure elements that might exist. It would be wise to have a plan to manage zonular dehiscence, including pupil hooks to stabilize the capsulorhexis if needed. The pupil might not dilate well because of iris and ciliary body damage, and the hooks can be used for both. Having the anterior vitrector handy would not be inappropriate because there might be vitreous prolapse into the anterior chamber once the lens has been removed. If it is appropriate to implant an IOL, the following applies: If the capsular bag is intact and stable, a 1piece IOL could be implanted in the bag. If there are concerns about bag stability, it would be best to use a 3-piece IOL and implant it in the sulcus. Occasionally, it might be better to place an aphakic IOL or to consider a glued IOL. Glaucoma stents are probably more appropriate as a secondary intervention if and when required. Arthur Cummings, MB ChB, MMED (Ophth), FCS(SA), FRCS(Ed) Dublin, Ireland
REFERENCES 1. Wolff SM, Zimmerman LE. Chronic secondary glaucoma; association with retrodisplacement of iris root and deepening of the anterior chamber angle secondary to contusion. Am J Ophthalmol 1962; 54:547–763 2. Delori F, Pomerantzeff O, Cox MS. Deformation of the globe under high-speed impact: its relation to contusion injuries. Invest Ophthalmol 1969; 8:290–301. Available at: http://www.iovs.org/ content/8/3/290.full.pdf. Accessed March 9, 2015
- High IOP and a shallow anterior chamber unresponsive to peripheral iridectomy (PI) without phacodonesis or intumescence indicate malignant glaucoma (also called ciliary block glaucoma and aqueous misdirection syndrome). Although seen mostly after incisional glaucoma surgery, malignant glaucoma can occur after trauma. Plateau iris and choroidal hemorrhage must be excluded. Preoperative UBM will show any ciliary body rotation, choroidal effusion, and clear collection of fluid behind the vitreous body. With its shorter AL, the fellow eye should be more hyperopic, yet the eyes' refractions are identical. With an anteriorly displaced lens, the right eye should become more myopic. Possible explanations include inaccurate UBM associated with loculated fluid or a change in sound transmission through dense vitreous, poor refraction because of cataract, or a change in corneal curvature with edema. Because the PI did not deepen the chamber, use preoperative atropine cycloplegia for this to confirm the diagnosis. Check for a relative afferent
J CATARACT REFRACT SURG - VOL 41, MAY 2015
CONSULTATION SECTION
exacerbated by anterior shifting of the swollen crystalline lens. The OCT image shows that the crystalline lens pushes against almost the complete posterior side of the iris. Thus, neodymium:YAG (Nd:YAG) laser iridectomy might not be effective in restoring aqueous flow. In this case, performing prompt biometry and phacoemulsification is the best option for interrupting the pressure build-up cycle and the inevitable glaucomatous nerve damage and cataract progression. Also, the pressure should be controlled to reduce the risk for intraoperative subchoroidal bleeding. A capsulorhexis and standard phacoemulsification should be attempted. During capsulorhexis, the extent of zonular weakness can be estimated. If there is significant nuclear instability, the bag can be fixated using 2 to 4 disposable iris hooks. In case of zonular dehiscence of more than 4 clock hours, a capsular tension ring (CTR) with an eyelet for scleral fixation or a capsular anchor can be used.3,4 These devices can be fixated using a 10-0 polypropylene suture under a Hoffman scleral pocket.5 In case of subtotal zonular dehiscence, the bag should be removed after phacoemulsification, and then an anterior vitrectomy performed and an irisfixated IOL implanted. In a case involving persistent symptomatic (traumatic) mydriasis, either pilocarpine 0.125% or thymoxamine 0.5% could be prescribed.
and angle closure. Before surgery begins, the 40 mm Hg IOP must be lowered by dehydration of the vitreous. To achieve this, I would give 200 to 400 mL of mannitol 20% and 500 mg of acetazolamide 2 to 4 hours preoperatively. In most cases, this regimen lowers the IOP enough that the anterior chamber then can be deepened using an OVD. If the crystalline lens shows abnormal movability during capsulorhexis, I would use iris retractors to stabilize the capsular bag and perform a very gentle, low-flow phacoemulsification with thorough hydrodissection, hydrodelineation, and chopping of the nucleus and would use a dispersive OVD to prevent aspiration of the floppy capsule. If the zonular dehiscence does not allow the implantation of a stable, well-centered posterior chamber IOL (PC IOL), I would use a CTR and fixate it with 1 or 2 transscleral polypropylene sutures. Using a long needle, the capsular bag can be penetrated without the risk for a large capsule rupture. Alternatively, a Cionni ring with an eyelet designed for scleral suture fixation can be used. Keeping the capsular bag in place is preferable to removing it and implanting an angle-supported, irisfixated anterior chamber IOL (AC IOL). Should the patient need filtering surgery later, an intact capsule–IOL diaphragm would be very advantageous because it would safely prevent vitreous prolapse into the anterior chamber or filtering site.
Maurits V. Joosse, MD, PhD The Hague, the Netherlands
Andreas Forrer, MD Aarau, Switzerland
1. Wolter JR. Coup-contrecoup mechanism of ocular injuries. Am J Ophthalmol 1963; 56:785–796 2. Wong TY, Klein BEK, Klein R, Tomany SC. Relation of ocular trauma to cortical, nuclear, and posterior subcapsular cataract: the Beaver Dam Eye Study. Br J Ophthalmol 2002; 86:152– 155. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/ PMC1770991/pdf/bjo08600152.pdf. Accessed March 9, 2015 3. Cionni RJ, Osher RH. Management of profound zonular dialysis or weakness with a new endocapsular ring designed for scleral fixation. J Cataract Refract Surg 1998; 24:1299–1306 4. Assia EI, Ton Y, Michaeli A. Capsule anchor to manage subluxated lenses: initial clinical experience. J Cataract Refract Surg 2009; 35:1372–1379 5. Hoffman RS, Fine IH, Packer M. Rozenberg I: Scleral fixation using suture retrieval through a scleral tunnel. J Cataract Refract Surg 2006; 32:1259–1263. Available at: http://www.finemd.com/ reprints/Scleral%20Fixation%20Using%20suture%20Retrieval %20Through%20a%20Scleral%20Tu.pdf. Accessed March 9, 2015
- I would perform a gonioscopy to rule out angle closure not caused by pupillary block, which would not be relieved by an Nd:YAG laser iridotomy. If the gonioscopy shows an open angle, look for angle recession to anticipate late-onset postoperative glaucoma. A detailed indirect ophthalmoscopy should be done to rule out peripheral retinal tears. Anterior segment OCT (AS-OCT) should be performed focusing on the posterior capsule to exclude dehiscence in the posterior capsule, which could cause the nucleus to drop during hydrodissection or phacoemulsification. In a shallow anterior chamber caused by a swollen lens, phacodonesis might not be visible in spite of zonular weakness. The operating surgeon might encounter zonular weakness for the first time during capsulorhexis. In such a situation, the condition might require implantation of a CTR or another sutured capsule-support device. A zero aspheric monofocal IOL has better tolerance to decentration and is preferred over a negative aspheric IOL in eyes with zonular weakness. Multifocal and accommodating IOLs are best avoided in such eyes.
REFERENCES
- After a blunt trauma to the globe, the most probable etiology of this very shallow anterior chamber is an extensive lesion of the zonular fibers with an anteriorly displaced lens, causing a ciliovitreolenticular block
J CATARACT REFRACT SURG - VOL 41, MAY 2015
CONSULTATION SECTION
In an eye with a preexisting posterior capsule defect, one may have to resort to a 3-piece PC IOL fixated in the sulcus. In an eye with both zonular dialysis and a posterior capsule defect, an iris-fixated IOL that preferably is fixated to the backside of the iris or a scleral-fixated PC IOL might be the only choices. This patient's eye should be monitored postoperatively for glaucoma and peripheral retinal tears. Suhas Haldipurkar, MD Mumbai, India
- I am assuming that the scheduled surgery is exploratory to assess the extent of the damage, address the cataract and increased IOP, and resolve other issues that are encountered. There is pain with accommodation and the lens is mobile, with the anterior chamber becoming shallower as the lens moves forward when the patient is lying face-down. The lens itself is decentered, too. All these symptoms suggest zonular disruption. The flat anterior chamber includes iris and ciliary body damage and possible angle recession, which are very common findings after blunt trauma.1 The high IOP could have a number of causes, including phacomorphic glaucoma, angle recession, blockage of the trabecular meshwork by red blood cells, and angle closure. If the patient is of African descent, it would make sense to check for sickle cell disease because sickle cells do not pass as readily through the trabecular meshwork. This could explain the blood in the anterior chamber and the IOP remaining high 10 days after the injury. The blunt trauma was severe, and the cornea might have made contact with the natural lens when it was displaced posteriorly. An 8.0 mm posterior movement of the cornea reduces the anteroposterior measurement of the eye by 41% at the time of injury and allows the equatorial sclera to expand by 28%, causing massive traction at the vitreous base.2 Therefore, it is vital to follow up regarding vitreoretinal health. The key risks subsequently are glaucoma and retinal detachment. The contact between the corneal endothelium and the lens might lead to endothelial cell damage, and so doing an endothelial cell count (ECC) might be useful for tracking endothelial cell health. Performing gonioscopy would be important for diagnosing angle recession. Because there are anterior and posterior capsule and subcapsular changes, the surgery would likely be cataract surgery. Replacing the thick crystalline lens (normally approximately 4.5 mm thick at this age) with an IOL (typically less than 1.0 mm thick) would largely decongest the anterior chamber and resolve the
1117
phacomorphic and angle-closure elements that might exist. It would be wise to have a plan to manage zonular dehiscence, including pupil hooks to stabilize the capsulorhexis if needed. The pupil might not dilate well because of iris and ciliary body damage, and the hooks can be used for both. Having the anterior vitrector handy would not be inappropriate because there might be vitreous prolapse into the anterior chamber once the lens has been removed. If it is appropriate to implant an IOL, the following applies: If the capsular bag is intact and stable, a 1piece IOL could be implanted in the bag. If there are concerns about bag stability, it would be best to use a 3-piece IOL and implant it in the sulcus. Occasionally, it might be better to place an aphakic IOL or to consider a glued IOL. Glaucoma stents are probably more appropriate as a secondary intervention if and when required. Arthur Cummings, MB ChB, MMED (Ophth), FCS(SA), FRCS(Ed) Dublin, Ireland
REFERENCES 1. Wolff SM, Zimmerman LE. Chronic secondary glaucoma; association with retrodisplacement of iris root and deepening of the anterior chamber angle secondary to contusion. Am J Ophthalmol 1962; 54:547–763 2. Delori F, Pomerantzeff O, Cox MS. Deformation of the globe under high-speed impact: its relation to contusion injuries. Invest Ophthalmol 1969; 8:290–301. Available at: http://www.iovs.org/ content/8/3/290.full.pdf. Accessed March 9, 2015
- High IOP and a shallow anterior chamber unresponsive to peripheral iridectomy (PI) without phacodonesis or intumescence indicate malignant glaucoma (also called ciliary block glaucoma and aqueous misdirection syndrome). Although seen mostly after incisional glaucoma surgery, malignant glaucoma can occur after trauma. Plateau iris and choroidal hemorrhage must be excluded. Preoperative UBM will show any ciliary body rotation, choroidal effusion, and clear collection of fluid behind the vitreous body. With its shorter AL, the fellow eye should be more hyperopic, yet the eyes' refractions are identical. With an anteriorly displaced lens, the right eye should become more myopic. Possible explanations include inaccurate UBM associated with loculated fluid or a change in sound transmission through dense vitreous, poor refraction because of cataract, or a change in corneal curvature with edema. Because the PI did not deepen the chamber, use preoperative atropine cycloplegia for this to confirm the diagnosis. Check for a relative afferent
J CATARACT REFRACT SURG - VOL 41, MAY 2015