Abstract Purpose: To determine whether Healon GV® or Healon® (both sodium hyaluronate products) maintains space better during phacoemulsification with intraocular lens (IOL) implantation. Setting: Department of Ophthalmology, Friedrich-Schiller-University of Jena, Germany. Methods: This double-blind, randomized clinical trial comprised 60 patients (30 Healon GV, 30 Healon) eligible for cataract surgery. Patients were evaluated 6 and 24 hours and 5 days postoperatively. A digital slide gauge mounted on an operating microscope was used to measure the distance between the iris and epithelial side of the cornea before surgery and before and after capsulorhexis. The distance between the anterior and posterior lens capsules (i.e., space in the capsular bag) was also measured before and after IOL insertion. The surgeon's objective opinion of the products was evaluated. Results: The mean anterior chamber depth after capsulorhexis was significantly greater in the Healon GV than in the Healon group (P = .003). The mean distance between the anterior and the posterior lens capsules was significantly larger in the Healon GV than in the Healon group before and after IOL insertion. The subjective evaluation of space-maintaining capacity during surgery also favored Healon GV. Healon was considered easier to inject and remove from the eye. Conclusion: Healon GV had better space-maintaining capacity than Healon during cataract surgery with phacoemulsification and IOL insertion.