## 3 Results  
This retrospective chart review identified 51 eyes of 51 patients who underwent FLACS. Their mean age was 67.14 \(\pm\) 8.38 years (range 52 to 86) and 35 (68.6%) patients were female. The patient demographics are shown in Table 1. \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter** & **Total (51 Eyes, 51 Patients)** \\ \hline Mean age (years) \(\pm\) SD 1, (range) & 67.14 \(\pm\) 8.38 (52–86) \\ Female, \(n\) (\%) & 35 (68.6) \\ Laterality, right eye, \(n\) (\%) & 19 (37.3) \\ \hline \hline \end{tabular} 1 SD = standard deviation.  
\end{table} 
Table 1: Basic demographics. There were no significant changes in the number of eyes with an abnormal osmolarity result (\(\geq\)310 mOsm/L) between baseline and at D1, W1, and M1 in the study eye, with values of 27 (52.9%), 31 (60.8%), 20 (39.2%), and 23 (45.1%), respectively. Mean tear osmolarity also showed no significant postoperative changes in post hoc analysis between baseline and at D1, W1, and M1, with average values of 310.92 \(\pm\) 16.52, 309.75 \(\pm\) 15.93, 303.78 \(\pm\) 15.99, and 304.69 \(\pm\) 14.97 mOsm/L, respectively. Significant changes in MMP-9 after FLACS were seen in both the number of eyes with abnormal results and their average grade. At D1, both the number of eyes with abnormal results and the mean MMP-9 grade increased significantly compared to the baseline, with values of 46 eyes (90.2%) and 1.94 \(\pm\) 0.97 at baseline and 51 eyes (100%, \(p\) = 0.010) and 3.55 \(\pm\) 0. No significant changes were seen in the number of abnormal overall OSDI results or the mean overall OSDI score 1-month postoperatively compared with preoperatively. However, the ocular discomfort subscale score significantly increased at M1 (\(p\) < 0.001) while the visual function subscale improved with significance at M1 (\(p\) < 0.001). There was no significant change in the environmental triggers subscale score (Table 3). In the subgroup analysis, no significant differences were found in tear osmolarity, MMP-9, or the OSDI values between the preoperative normal and abnormal values of both tear osmolarity (Table 4) and MMP-9 (Table 5). \begin{table}
\begin{tabular}{l c c c} \hline \hline
**Parameter** & **Osmolarity (+)** & **Osmolarity (-)** & \\
**Parameter** & **(_n_ = 27)** & **(_n_ = 24)** & \(p\) \\ \hline Osmolarity & & & \\ Abnormal, \(n\) (\%) & & & \\
1 day & 18 (66.7) & 13 (54.2) & 0.361 [3] \\
1 week & 10 (37.0) & 10 (41.7) & 0.735 [3] \\
1 month & 15(55.6) & 8 (33.3) & 0.111 [3] \\ Average, mean (SD) & & & \\ Baseline & 323.22 (12.32) & 297.08 (6.67) & \textless{}0.001 [2] \\
1 day & 310.70 (16.42) & 308.67 (15.65) & 0.653 [1] \\
1 week & 304.67 (16.02) & 302.79 (16.24) & 0.734 [2] \\
1 month & 307.93 (15.56) & 301.04 (13.69) & 0.102 [1] \\ MMP-9 & & & \\ Abnormal, \(n\) (\%) & & & \\ Baseline & 24 (88.9) & 22 (91.7) & 0.192 [4] \\
1 day & 27 (100) & 24 (100) & \\
1 week & 24 (88.9) & 22 (91.7) & 0.739 [4] \\
1 month & 15 (55.6) & 14 (58.3) & 0.842 [3] \\ Average, mean (SD) & & & \\ Baseline & 1.78 (1.05) & 2.12 (0.85) & 0.151 [2] \\
1 day & 3.70 (0.54) & 3.38 (0.88) & 0.169 [2] \\
1 week & 1.52 (1.01) & 1.96 (1.23) & 0.192 [2] \\
1 month & 0.78 (0.80) & 0.87 (0.85) & 0.694 [2] \\ OSDI & Abnormal, \(n\) (\%) & & \\ Baseline & 21 (77.8) & 18 (75.0) & 0.815 [3] \\
1 month & 20 (74.1) & 15 (62.5) & 0.374 [3] \\ Average, mean (SD) & & & \\ Baseline & 27.66 (18.27) & 31.04 (22.75) & 0.706 [2] \\
1 month & 29.91 (21.37) & 25.72 (18.39) & 0.590 [2] \\ Ocular discomfort, mean (SD) & & & \\ Baseline & 19.63 (15.38) & 19.38 (14.09) & 0.954 [2] \\
1 month & 35.65 (24.79) & 29.00 (17.18) & 0.369 [2] \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Subgroup analysis according to the preoperative osmolarity result.