Any eye with chronic or recurrent uveitis may develop cataract as a result of the inflammation or the corticosteroids used for treatment. Indications for cataract surgery in uveitic eyes are the same as for all cataracts: when the cataract causes functional impairment that interferes with activities of daily living, when the cataract is responsible for at least a portion of that decrease in vision, and when functional improvement is likely to occur after cataract extraction (a particularly important consideration in children who may develop amblyopia). Additional considerations for cataract surgery in uveitic eyes are whether a cataract precludes the clinician from obtaining an adequate view of the fundus—thereby inhibiting appropriate monitoring of posterior segment disease or health—and the degree to which the uveitis has been controlled.
As mentioned earlier, careful preoperative evaluation is necessary to ascertain whether the cataract is actually contributing to visual dysfunction. Vision loss in uveitis may stem from a variety of other ocular complications of uveitis, including corneal or vitreous opacity, macular edema, macular atrophy or fibrosis, and glaucoma.
Studies have shown that phacoemulsification with posterior chamber (in-the-bag) intraocular lens (IOL) implantation effectively improves vision and is well tolerated in many eyes with uveitis, even over long periods.
Uveitic eyes are at greater risk for postoperative complications than nonuveitic eyes. Thus, careful planning, including preoperative medical management and the timing of the procedure, is critical. The key to a successful visual outcome is meticulous long-term control of inflammation prior to surgery. Common advice is to achieve the best control possible without flare-ups for at least 3 months prior to cataract surgery. The rationale is to ensure the eye is stable on the current medical regimen and the tissues are allowed to recover from prior inflammation before the eye is challenged with a surgical procedure that can lead to a profound postoperative inflammatory response.
The recommendation for maintenance of maximum control for at least 3 months before surgery is based on retrospective clinical case series and clinical experience; no prospective or controlled trials provide definitive data. As such, exceptions may be made when the considered opinion of the treating physician is that a delay in surgery is not indicated. Examples include eyes with mild uveitis lacking sequelae, disorders that have a good surgical prognosis (eg, Fuchs heterochromic uveitis), or special circumstances such as lens-induced uveitis or the need to view the posterior segment (eg, to repair a rhegmatogenous retinal detachment). It should be noted that the “best control possible” is not achieved by incomplete control with corticosteroids alone. The clinician must utilize all appropriate means for control, including immunosuppression if needed. If the clinician is uncomfortable with such means of treatment, then referral to a specialist with that experience is required before proceeding with cataract surgery.
Once appropriate control is achieved, preoperative pulsing with oral corticosteroids (0.5–1.0 mg/kg/day, usually for 3 days, although opinions vary as to dose and duration) and/or intensive topical corticosteroid treatment should be considered. Prospective comparative data regarding optimal perioperative inflammatory control are lacking, and accepted regimens largely rely on the surgeon’s preference and experience. Dosages may be tapered over weeks to months after surgery, based on the severity of the underlying uveitis before surgery and the postoperative inflammatory response. Postoperative use of nonsteroidal anti-inflammatory drugs (NSAIDs) has not been studied in eyes with uveitis but is frequently employed in nonuveitic eyes that are undergoing cataract surgery, with the goal of preventing uveitic macular edema (UME). Corneal toxicity from topical NSAIDs used concurrently with topical corticosteroids is a concern. Patients with certain infectious uveitides (eg, uveitis caused by Toxoplasma gondii infection and herpetic uveitis) may require perioperative prophylactic antimicrobial therapy to prevent surgically induced recurrence—preoperative oral corticosteroids are usually not given.
Cataract surgery in uveitic eyes is generally more complex than in nonuveitic eyes because of the potential presence of sequelae of uveitis, including posterior synechiae, pupillary membranes, corneal edema or opacity, and hypotony. Entrance into the eye through a clear corneal approach is often used and may be particularly desirable in cases of scleritis that may be prone to postoperative scleral necrosis. Posterior synechiae and pupillary miosis may require mechanical or viscoelastic pupil stretching, sphincterotomies, or the use of flexible iris retractors (Video 14-1).
Synechiolysis, placement of iris dilator, and capsular staining in a patient with uveitis.
Courtesy of Russell W. Read, MD, PhD.
Access the video at www.aao.org/bcscvideo_section09.
Although a curvilinear capsulorrhexis is preferred, a fibrotic anterior capsule may be more difficult to open with a capsulorrhexis than with a can-opener capsulotomy. Zonular insufficiency may be present, which may make phacoemulsification and lens implantation challenging or impossible. In such cases, there may be few alternatives, and the surgeon’s preference may be to perform pars plana lensectomy and vitrectomy and avoid placing an IOL because of the lack of capsular support or zonular dehiscence. Fortunately, this scenario is rare. Meticulous cortical cleanup is important to avoid leaving behind potentially proinflammatory material in the eye. For IOL choice, many surgeons prefer hydrophobic acrylic posterior chamber IOLs placed in the capsular bag. The possibility of future vitreoretinal surgery with silicone oil should be considered when deciding whether to use silicone IOLs. At the conclusion of the surgery, periocular or intravitreal corticosteroids may be administered. Postoperatively, immunomodulation is continued and supplemented with liberal use of topical corticosteroids, which are slowly tapered.
Phacoemulsification with IOL implantation can also be done in conjunction with pars plana vitrectomy if clinical or ultrasonographic findings suggest the presence of substantial vision-limiting vitreous debris or macular pathology such as epiretinal membranes. When there has been significant structural damage from inflammation, or in cases in which the surgical prognosis is more guarded (eg, in JIA-associated uveitis), vitrectomy and aphakia may be the best course. Relative contraindications for IOL implantation include the prior development of rubeosis, a history of extensive membrane formation, and hypotony, although even in these circumstances, an IOL may be used in select cases.
There is controversy regarding IOL placement in children with JIA-associated uveitic cataracts. Avoiding aphakia in children is desirable but may not always be in the best interest of the patient. Choosing the proper IOL power, especially in children under the age of 10 years, is difficult because of normal ocular/orbital growth. (For more information about IOL use in children, see BCSC Section 6, Pediatric Ophthalmology and Strabismus.) Regardless, the most important step in the treatment of these children is stringent control of preoperative and postoperative intraocular inflammation using corticosteroids and immunomodulatory therapy (IMT). If IOLs are used, in-the-bag implantation of acrylic IOLs and primary posterior capsulorrhexis are preferred in children. Silicone IOLs are not typically used in uveitic cataracts. These IOLs may lead to suboptimal outcomes and complicate future vitreoretinal surgery. Some surgeons may also perform a core anterior vitrectomy through the posterior capsulorrhexis prior to IOL placement. Administration of intraocular corticosteroids at the end of the procedure is extremely useful for controlling postoperative inflammation and UME. If these methods are used, 75% of patients will obtain a visual acuity of better than 20/40.
Mehta S, Linton MM, Kempen JH. Outcomes of cataract surgery in patients with uveitis: a systematic review and meta-analysis. Am J Ophthalmol. 2014;158(4):676–692.
Sen HN, Abreu FM, Louis TA, et al; Multicenter Uveitis Steroid Treatment (MUST) Trial and Follow-up Study Research Group. Cataract surgery outcomes in uveitis: the Multicenter Uveitis Steroid Treatment trial. Ophthalmology. 2016;123(1):183–190.
Excerpted from BCSC 2020-2021 series: Section 9 - Uveitis and Ocular Inflammation. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.