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

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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

May consultation #6.

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