[Pseudophakic cystoid macular edema. Assessment with optical coherence tomography]

To determine the incidence of cystoid macular edema (CME) by means of clinical evaluation and subclinical assessment by means of ocular coherence tomography (OCT), and to compare the incidence between diabetic and non-diabetic groups of patients.

Prospective study of 260 consecutive cataract surgeries operated from September 2004 to March 2005. The procedures were performed by means of phacoemulsification plus intraocular acrylic lens implantation. Group A: 208 eyes of non-diabetic patients; Group B: 42 eyes of patients with diabetes and Group C: 10 eyes of diabetic patients with macular edema that received an intravitreal injection of triamcinolone at the end of surgery. Postoperative follow-up visits were performed 6 days (basal visit), 5 weeks and 12 weeks after surgery. Each visit included posterior pole biomicroscopy and OCT.

Central macular thickness measured by OCT was significantly increased in group B compared with group A (241.6 versus 204.6 microm; p<0.001). No clinical evidence of CME was found in group A, although 4 eyes (1.92%) showed macular thickness equal to or greater than 43.74 microm (2 standard deviations of the basal value for group A). In group B, clinical evidence of CME was found in 6 eyes, with decreased visual acuities (14.2%). The differences between these groups were statistically significant (p<0.001). The 10 eyes that received an intravitreal injection of triamcinolone after the surgical procedure showed a mean decrease in central retinal thickness of 77 microm after 12 weeks postoperative.

This study has shown a low incidence of clinical CME. OCT showed increased macular thickness in both groups of patients in a small percentage of cases, and significantly increased macular thickness in diabetic patients.