To investigate the change of intraocular pressure (IOP) and ocular pulse amplitude (OPA) measured by dynamic contour tonometry (DCT) after cataract surgery and to identify the influencing factors related with OPA change after cataract extraction.

The present study included 32 patients who underwent unilateral cataract surgery and the non-operated fellow eyes were used as control. IOP was measured by Goldman applanation tonometry (GAT) and Pascal DCT preoperatively, and 3 months postoperatively. Additionally, OPA was measured by Pascal DCT preoperatively, and 3 months postoperatively. Axial length (AL), anterior chamber depth (ACD), and central corneal thickness (CCT) were measured preoperatively.

After cataract surgery, IOP by GAT, IOP by DCT, and OPA decreased significantly with a mean decrement of 1.3 mm Hg, 1.6 mm Hg, and 0.5 mm Hg, respectively ( p < 0.05). OPA was significantly correlated with IOP by GAT ( r = 0.497, p = 0.004) and IOP by DCT ( r = 0.421, p = 0.016) preoperatively. OPA was correlated with GAT ( r = 0.357, p = 0.045) but not with DCT ( r = 0.224, p > 0.05) postoperatively. The most important factor influencing the decrement of IOP by GAT, IOP by DCT, and OPA after cataract surgery was the preoperative level of their measurements ( r = 0.382, p < 0.05 in GAT, r = 0.807, p < 0.001 in DCT, r = 0.627, p < 0.001 in OPA). In addition, the OPA decrement after cataract surgery was significantly correlated with age ( r = -0.370, p = 0.037), and was not correlated with AL, ACD, and CCT.

Both IOP and OPA decreased after cataract surgery, which appears to influence the relationship between IOP and OPA. The correlation between OPA decrement and age may be related to increased ocular rigidity with aging.