Part 3 • Medical Therapy and Surgical Intervention Chapter 8 Role of Surgery in the Patient with Uveitis

lensectomy, that their disease was easier to treat, and in some there was resolution of macular edema. We have found that vitrectomy is useful in helping to observe the posterior pole and thus follow the course of disease, and the procedure appears to make it easier for steroid to penetrate intraocularly. However, we have not found it to be an effective therapy when used alone, as had been suggested by Kaplan72 and Stavrou et al.73 who found that in 44% of 43 eyes there was an improvement in the course of intermediate uveitis. Bovey and colleagues74 performed vitrectomy or cataract extraction or both in 30 eyes and found an improvement in visual acuity but no decrease in the inflammatory process, nor did Nolle75 and Eckardt in nine patients with multifocal chorioretinitis who underwent vitrectomy. Guttfleisch et al.76 performed pars plana vitrectomy coupled with intravitreal injections of triamcinolone to treat cystoid macular edema. CME improved in 58% of patients in the first 6 weeks, but the effect was transient, with 85% of patients additionally showing cataract progression, and increases in intraocular pressure seen in over one-quarter of 19 patients treated. Indeed, a small randomized comparing vitrectomy (n = 12) to medical therapy (n = 11) for CME showed that in the vitrectomized group CME improved in four patients, remained unchanged in seven, and worsened in one.77 In a very good review of 44 interventional case series involving 1575 patients, Becker and Davis78 found that in 39 articles the visual acuity of vitrectomized uveitic eyes improved in 68% of cases, was unchanged in 20%, and was worse in 12%. The findings of CME in patients halved. The devil is in the details. When evaluating these findings so many factors complicate the interpretation that is most difficult to arrive at a reasonable clinical conclusion. One possible exception to this is reported salutary effect of vitrectomy on juvenile uveitis.

The prognosis for visual improvement after removal of the epiretinal membrane is worse in eyes with uveitis than in eyes with idiopathic membranes.79 Retinal detachment is surprisingly not that uncommon in these patients. In one review of 1387 patients,80 43 (46 eyes) had a retinal detachment (3.1% of the total). It was most frequently associated with panuveitis and eyes with infectious disease. The uveitis was active in almost one half of the patients studied. In addition, after repair of a rhegmatogenous retinal detachment by standard scleral buckling procedures there is probably a higher risk of proliferative vitreoretinopathy (PVR) in eyes with ongoing chronic inflammation, because the inflammatory mediators stimulate fibrous tissue proliferation. It was seen in 30% of the patients reported by Kerkhoff and associates.80 The development of PVR usually necessitates additional surgery with membrane stripping and gas– fluid exchange. After this procedure, control of the inflammation is critical or the membranes may reform. Re­ attachment occurs in a small minority of patients after one operation, whereas anatomic reattachment occurs in close to 90% of patients, and the final vision is poor (20/200 or worse in close to three-quarters of patients).80

Serous detachment is a commonly faced problem in uveitis and is almost always treated medically. However, there are stubborn cases that may simply not respond to therapy, either for physical reasons such as traction or for reasons that are unclear. Surgical drainage can be contemplated, often with reattachment succeeding.81 Another type

of drainage reported in the literature is puncture of cystoid macular edema lesions. This may flatten the cyst but will not result in an improvement of vision.82

The repair of giant retinal tears that may complicate viral retinitis, such as acute retinal necrosis or cytomegalovirus retinitis, is not always best managed by scleral buckling. The retina in these diseases has become necrotic and areas may be ischemic. The use of a high buckle might increase this ischemia, leading to retinal neovascularization. An alternative solution has been to perform a pars plana vitrectomy and to reattach the retina with gas or silicone oil tamponade and laser photocoagulation.83

Laser treatment

Lasers can be used to perform peripheral iridectomies and posterior capsulotomies, to cut pupillary membranes, to clear deposits off the anterior surface of an IOL, and to treat retinal or subretinal neovascularization. The use of the laser, however, does not eliminate the possibility of inducing inflammation.

In the anterior segment either the YAG or the argon laser can be used to perform an iridotomy. Although the procedure is probably technically easier with the YAG laser, there is the theoretic possibility that the incidence of hyphema from the vascular, inflamed iris may be greater after YAG than after argon laser treatment because the YAG laser does not coagulate tissue. This comparison has not been studied in patients with uveitis. Posterior capsulotomy is easily performed with the YAG laser unless there has been a significant fibrous reaction or calcification as a result of the inflammation. Pupillary membranes can occasionally be so dense that the laser procedure becomes very long, necessitates the use of high energies, or cannot be successfully performed at all (Fig. 8-9). In addition, although an uncomplicated capsulotomy can be performed with only a few bursts of laser energy

– and at the time of the procedure it appears that little has been disrupted within the eye – the energy delivered by the YAG laser does alter the blood–aqueous barrier.84 We have observed several patients with chronic uveitis who have had severe flares of inflammation associated with a marked temporary decrease in acuity 1 day after YAG laser capsulotomy.

Figure 8-9.  YAG laser membrane disruption in a patient with dense pupillary membrane after cataract surgery.