Measuring anterior chamber inflammation after cataract surgery: a review of the literature focusing on the correlation with cystoid macular edema

Cystoid macular edema (CME) is an infrequent, though potentially visually impairing, complication after uneventful cataract surgery. Rupture of the blood-aqueous barrier, with leakage of serum proteins into the aqueous humour, is the main pathogenic factor. However, only a few studies investigated the potential correlation between anterior chamber (AC) inflammation and the risk of cystoid macular changes occurring after surgery. This review aims to identify evidence of a correlation between AC inflammation and the risk of pseudophakic CME. One hundred eighty-seven prospective trials investigating AC inflammation after uncomplicated cataract surgery were identified. Methods of analysis of AC inflammation and the frequency of macular changes were recorded. In the majority (51%) of the studies, inflammation was assessed by clinical grading, followed by laser flare and cell photometry (LFCP) (42%) and aqueous humour sample (4%). Few studies (4%) adopted a combined LFCP and aqueous sample or clinical grading analysis. Sixteen (9%) studies investigated AC inflammation and macular changes by OCT (7%) or fluorescein angiography (2%). Correlation between the amount of postoperative AC inflammation and frequency of CME was documented in 7 studies, not confirmed in 2 studies, and not examined in the other 7. LFCP, more than the other methods of analysis, correlated with the frequency of CME postoperatively. Investigation of the relationship between AC inflammation and the risk of CME changes requires the adoption of quantitative methods of analysis of the inflammatory response after surgery. For this purpose, due to the low level of inflammation in the AC after uncomplicated cataract surgery, LFCP, more than subjective clinical grading, seems a more sensitive and reproducible method of measurement. Inflammation assessment after cataract surgery has a potential role in predicting the risk of CME development and may help to titrate the duration and intensity of treatment in relation to the surgical inflammatory response.