Quantification of Blood-Aqueous Barrier Breakdown after Phacoemulsification in Fuchs’ Heterochromic Uveitis

Abstract

Purpose: To quantify the breakdown of the blood-aqueous barrier (BAB) following phacoemulsification with posterior chamber lens implantation in eyes with Fuchs’ heterochromic uveitis (FHU). Patients and Methods: In this retrospective study, 19 eyes of 19 patients with FHU (mean age 38 ± 14 years) and 35 eyes of 35 patients with senile cataracts (mean age 63 ± 9 years) underwent phacoemulsification with one-piece PMMA posterior chamber lens implantation. Aqueous flare was quantified using the laser flare-cell meter (LFCM, Kowa FC-1000) following medical pupillary dilation preoperatively and 1, 3, and 5 days, then 1 and 6 weeks and 6 months postoperatively. Results: Mean preoperative aqueous flare (in photon counts per millisecond) in FHU vs. controls was 11.7 ± 3.5 vs. 5.8 ± 1.7. Following cataract surgery, mean aqueous flare increased to 27.8 ± 4.4 vs. 16.0 ± 4.5 on day 1, decreased to 23.6 ± 4.0 vs. 11.8 ± 3.5 on day 3, and to 18.0 ± 3.0 vs. 9.5 ± 1.7 on day 5. In FHU eyes, it was 13.9 ± 2.7 after 1 week, and had returned to preoperative levels after 6 weeks (10.9 ± 2.5) and remained stable for up to 6 months (mean 10.3 ± 2.2). Pre- and postoperatively, aqueous flare values were 2–3 times higher in FHU eyes than in control eyes with senile cataract (p = 0.01). No postoperative complications such as fibrin formation, synechiae, macrophages on the intraocular lens optic or endophthalmitis were observed in any of the patients. Conclusions: BAB breakdown following phacoemulsification with posterior chamber lens implantation is relatively mild in eyes with FHU and the BAB appears to be fully reestablished to preoperative levels 6 weeks postoperatively, explaining the usually good outcome of cataract surgery in this condition.

Laser flare photometry and its use in uveitis

“…It is noteworthy that flare levels do not change with anti-inflammatory Review CME treatment and remain stable over months or years in this entity [7,37,38]. A relatively mild and stable breakdown of the blood-aqueous barrier has been reported in FU even after cataract surgery [33,36,39,40]. LFP studies have confirmed the clinical observations on the disease course and helped in explaining the benign nature of FU [41].…”

“…A relatively mild disruption of the blood-aqueous barrier has been shown in eyes with Fuchs' uveitis (FU), with mean flare values ranging from 6.4 to 12.1 ph/ms that were still significantly higher compared with fellow eyes or eyes of healthy controls [32][33][34][35][36][37]. It is noteworthy that flare levels do not change with anti-inflammatory Review CME treatment and remain stable over months or years in this entity [7,37,38].…”

Aqueous flare and cells in Fuchs syndrome

“…The accuracy and reproducibility of the method have been shown in several studies. [12][13][14][15][16][17][18][19][20][21][22][23] Using LFCM, we recently showed breakdown of the BAB and presence of anterior chamber cells in Chinese patients with Fuchs syndrome. 7 The present study confirmed our previous observation in another group of Chinese patients with Fuchs syndrome using the same technique.…”

Laser flare photometry: a noninvasive, objective, and quantitative method to measure intraocular inflammation

“…However, breakdown of the blood-aqueous barrier is relatively mild in FUS, with mean flare values ranging from 6.4 to 12.1 ph/ms [46,[54][55][56]. In eyes with some but not all clinical features of this entity, for example in eyes with diffuse keratic precipitates, mild iris atrophy, vitreous cells and debris but without heterochromia or cataract, low flare readings help the differential diagnosis from other forms of chronic granulomatous uveitis.…”