Impact of 0.1% sodium hyaluronate and 0.2% sodium hyaluronate artificial tears on postoperative discomfort following cataract extraction surgery: a comparative study

Background: Recent artificial tear preparations have provided 0.2% concentration of sodium hyaluronate. However, no published data exist on their potential superiority against 0.1% in alleviating dry-eye-disease symptoms in cataract extraction surgery. Methods: A total of 180 patients that underwent cataract extraction surgery were randomly divided into 2 groups according to their postoperative regime: Study group (SG) received fixed combination of tobramycin and dexamethasone (FCTD) quid for 3 weeks, and additionally 0.2% sodium hyaluronate provided in the COMOD (R) device quid for 6 weeks. Control group (CG) received fixed combination of tobramycin and dexamethasone (FL D) quid for 3 weeks, and additionally 0.1% sodium hyaluronate provided in the COMOD (R) device quid for 6 weeks. The following indexes were evaluated at 3 postoperative checkpoints: 1) Surface discomfort index (SDI) which was derived by four direct 10-scale Likert-type questions that were addressed to the patient and pertained to: a) foreign body sensation (FBS), b) blinking discomfort (BD), c) stinging sensation (SS), d) tearing sensation (TS), 2) Tear break up time (TBUT), 3) Schirmer's test, 4) Central corneal thickness (CCT), and 4) Central Corneal Sensitivity (CCS). Results: Both groups showed reduced CCS values at all postoperative examination points; however, SG participants had significantly better CCS (all p < 0.05). SG had better TBUT than CG at the 3rd (p = 0.03) and 6th examination points (p = 0.04). Moreover, SG had better SDI scores at the 3rd (SDI = 9.26 +/- 0.55) and 6th weeks (SDI = 9.47 +/- 0.48) vs. CG participants (p = 0.03 and p < 0.01, respectively). Conclusion: The increased 0.2% sodium hyaluronate concentration in the artificial tears provided in the COMOD (R) device seems to address dry-eye-disease symptoms better in patients who underwent phacoemulsification surgery than the 0.1% concentration.