The Effect of Hydrodynamic Parameters on Corneal Endothelial Cell Loss After Phacoemulsification
Condition: Cataract
MeSH terms: Cataract; Corneal Endothelial Cell Loss
Study type: Interventional

Summary: 
      The purpose of this study is to compare two surgical techniques (high vacuum and low vacuum)
      on corneal endothelium after phacoemulsification.
    

Detailed description: 
      Patients aged 50 to 70 years old with moderate lens opacities (nuclear sclerosis of 3+) were
      included. The exclusion criteria were: 1-previous corneal pathology (dystrophic or
      degenerative such as Fuchs' endothelial dystrophy or advanced trachoma), 2- pseudoexfoliation
      syndrome (PEX), 3- history of intra ocular surgery, 4- glaucoma or ocular hypertension, 5-
      eyes with a history of anterior uveitis, 6- diabetes mellitus, 7- anterior chamber depth
      (ACD) less than 2.5 mm or more than 4 mm, 8- axial length less than 21 mm or more than 25 mm,
      9- density of endothelial cells less than 1500 cells per mm2, 10- polymegatism (CV > 0.4),
      11- keratometric astigmatism more than 1.5 Diopters (D), 12- history of contact lens usage,
      13- Intra-operative complications (posterior capsule rupture with or without vitreous loss),
      14- postoperative uveitis, 15- postoperative surgical wound leakage, 16- deep-set eye, and
      17- size of dilated pupil less than 6 mm. Nucleus density was evaluated using the LOCS III
      classification system Patients were divided in 2 groups randomly: Group 1 included those
      candidates for phacoemulsification using high hydrodynamic parameter: 400 mmHg vacuum and 40
      ml/min flow rate (high vacuum technique) whereas group 2 consisted of patients who underwent
      phacoemulsification using low hydrodynamic parameters: 200 mmHg vacuum and 20 ml/min flow
      rate (low vacuum technique). All surgeries were performed by one surgeon using stop and chop
      technique with sovereign (white star technology) (AMO, USA). During sculpting stage, vacuum
      was 40mmHg and flow rate is 20ml/min, in both groups. Irrigation aspiration of cortical
      material and viscoelastic were bimanually and semi automatically performed with flow rate of
      30ml/min.

      Total ultrasound power and total volume of BSS in both groups were measured. Pachymetry,
      endothelial cell density, polymegathism, before and 1, 6 and 12 weeks after intervention were
      also evaluated. Statistically analysis of data included univariate (student t-test and x2)
      and multivariate (regression model) analysis of postoperative results.
    

Intervention name(s): phacoemulsification using either high vacuum or low vacuum techniques
Intervention type(s): Procedure
Intervention description(s): All surgeries were performed using Sovereign phacoemulsification system (AMO) using Whitestar technology.
Other intervention name(s): stop and chop technique
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: Phacoemulsification; Corneal endothelial cell loss; Hydrodynamic parameters; Total ultrasound energy; Total infused fluids