Identifying Appropriate Patients for Treatment
Detecting the presence of posterior uveitis is not particularly difficult for a retinal physician. The signs and symptoms are usually easily recognized. Cells may be visible in the vitreous, white or yellowish-white lesions may be seen in the retina or choroid, and exudative retinal detachment, optic disk edema or retinal vasculitis may be present. Symptoms can include eye pain and sensitivity to light, although they occur less often than floaters or decreased vision. Determining the best treatment option, however, is a much bigger challenge. Therapy must be tailored to each individual patient based on the history and severity of the inflammation and whether an underlying systemic cause must also be addressed.
Retinal physicians can coordinate care with other healthcare providers in an effort to determine the exact cause of posterior uveitis. However, a high percentage of cases are idiopathic, and while laboratory testing such as antinuclear antibody, purified protein derivative, Lyme titer, and HLA-B51 or HLA-A29 may be helpful for determining an underlying cause, conducting a random battery of ancillary tests is costly and often not very productive. Thorough history and physical exam, perhaps followed by targeted testing, are more likely to yield satisfactory answers.
That said, whether or not an underlying systemic cause for noninfectious posterior uveitis can be identified, the goals of treatment for the retinal physician are the same: continuous control of the ocular inflammation to prevent cumulative damage to vision with manageable side effects. In properly selected patients, the Retisert® implant (fluocinolone acetonide intravitreal implant 0.59 mg, Bausch + Lomb) can be an effective tool for achieving these goals.
FRAMEWORK FOR DECISION-MAKING
When determining which patients may benefit from Retisert, we must consider the type of uveitis, then weigh the risks and benefits of treatment with Retisert.
For example, patients who have posterior uveitis secondary to Behçet's syndrome, sympathetic ophthalmia or serpiginous choroiditis are often ideal candidates for Retisert. The ocular inflammation caused by these conditions tends to be aggressive and very difficult to control, even with systemic corticosteroids or other systemic immunosuppressive therapies. Retisert may provide effective control of the inflammation of the eye in these cases, often with a reduction in the use of systemic agents and, therefore, their side effects. Serpiginous choroiditis is not associated with a systemic disease; therefore, the ocular manifestations can be the sole driver of treatment.
Standard treatment for pars planitis is generally effective and the prognosis is favorable; however, I consider Retisert when the condition is idiopathic or if cystoid macular edema (CME) is recurrent. In either situation, repeated and unexplained bouts of inflammation due to uveitis may pose too great a threat to vision to not opt for continuous local control. As shown in Figures 1 and 2, the uveitis and its related CME were resolved in one eye after implantation of Retisert.
Figures 1 and 2. Clinical trials and experience have shown the Retisert implant (fluocinolone acetonide intravitreal implant 0.59 mg, Bausch + Lomb) is effective in treating posterior noninfectious uveitis. In this case, Retisert was used to treat birdshot chorioretinopathy, a subset of uveitis. The uveitis and related CME were resolved in the right eye of this patient following implantation of Retisert.
Many of the white dot syndromes, such as birdshot chorioretinopathy and multifocal choroiditis, tend to be aggressive, chronic and recurrent and may require extensive therapy, making Retisert an option for controlling them as well. Like serpiginous choroiditis, birdshot chorioretinopathy is primarily an ocular disease so treatment can focus solely on the ocular signs and symptoms.
Retisert can also be considered an effective potential therapy in cases of panuveitis due to Vogt-Koyanagi-Harada syndrome or sarcoidosis when standard therapy has been ineffective or inadequate or when a tapering of systemic therapies would be advantageous for the patient's overall health.
Retisert is contraindicated in posterior uveitis of infectious or neoplastic etiology. It is also contraindicated in active viral diseases of the cornea and conjunctiva. It should only be considered for patients suffering from chronic noninfectious uveitis affecting the posterior segment in which systemic corticosteroids or nonsteroidal immunosuppressive therapy would otherwise be required to prevent recurrence. However, the clinical benefit of Retisert and its ability to provide continuous control of intraocular inflammation must be weighed against the risk of surgery and the known side effects of the implant itself, mainly cataract progression and elevated IOP. These side effects must be considered, for each individual, and weighed against potential vision loss from the uveitis itself or the side effects of systemic treatment options.
When considering Retisert, first evaluate if the uveitis is improving, worsening or staying the same on the current treatment. Then consider how the patient is tolerating and responding to the current treatment. In some cases, the systemic treatment necessary to control an underlying disease is already at high levels, so the addition of Retisert may be considered — rather than a further increase in systemic dose — to provide control of the uveitis. In other cases, systemic therapy may be effective against the uveitis, but intolerable for the patient. Again, an overall goal of treatment is the ability to manage side effects, so in some patients, it is appropriate to consider an alternative treatment, such as Retisert. For example, Retisert may be a next step for a patient being treated with periocular steroid injections, which provide only intermittent uveitis control. Retisert may be an option for patients who require reduced systemic drug exposure. On the other hand, Retisert may not be a good option for a patient who is already losing vision due to glaucoma.
PRESERVING VISION AND AVOIDING SYSTEMIC SIDE EFFECTS
As long as the retinal physician is confident in his or her diagnosis of chronic noninfectious posterior uveitis, in particular that it is not infectious or neoplastic, Retisert can be an addition to the treatment armamentarium for carefully selected patients. It can be an option for balancing benefit and risk.
Most of my patients are willing to undergo treatment for cataract and elevated IOP in order to eliminate the diminished vision and complications from systemic steroids and other therapies that had been affecting them.