Intra-surgical Evaluation of CATS Tonometer Prism and Abbott Medical Optics Versus Alcon Phacoemulsification Machines

Intra-surgical Evaluation of CATS Tonometer Prism and AMO Versus Alcon Phacoemulsification Machines

This study will measure the dynamic real-time intraocular pressure (IOP) in the anterior chamber during standard phacoemulsification surgery.

What is known:

• Fluidics control is determined to be one of the primary drivers of physician decision making in choosing phacoemulsification equipment.
• Active pressure system fluidic control has a perceived and possibly real (based upon recent literature) improvement in intra-cameral IOP stability and reduced pressure fluctuations.
• Improved fluidics can allow for reduced dynamic IOP fluctuations, in-the-bag positioned phaco tip, and intra-cameral fluid flow all of which will likely improve corneal health post-operatively.

Inclusion Criteria:

• • Age 18 or greater

  • Bilateral cataracts for which phacoemulsification extraction and posterior IOL implantation has been planned for both eyes
  • Subjects able to give informed consent
  • Nuclear Sclerotic cataract graded 2+ or 3+
  • Naturally dilated pupil size (in dim light) > 4.0 mm (with no dilation medications) for both eyes
  • Preoperative corneal astigmatism of 2.5 D or less
  • Ages between 55 and 80
  • Availability, willingness, and sufficient cognitive awareness to comply with examination procedures

Exclusion Criteria:

• • Uncontrolled systemic disease that in the opinion of the Investigator would put the subject's heath at risk

  • Intraoperative complications
  • Subjects with only one functional eye
  • Those with one eye having poor or eccentric fixation
  • Mild or severe cataracts, predominantly posterior subcapsular cataracts
  • High corneal astigmatism (i.e. those eyes displaying an oval contact image)
  • Those with corneal scarring or who have had corneal surgery including corneal laser surgery
  • Microphthalmos
  • Buphthalmos
  • Severe Dry eyes
  • Blepharospasm
  • Nystagmus
  • Keratoconus
  • Any other corneal or conjunctival pathology or infection.
  • Central corneal thickness greater than 0,600 mm or less than 0,500 mm (2 standard deviations about the human mean)
  • Acute or chronic disease or illness that would increase risk or confound study results (e.g. diabetes mellitus, immunocompromised, etc.)
  • Uncontrolled systemic or ocular disease
  • History of ocular trauma or prior ocular surgery
  • Fuchs Dystrophy
  • Subjects who may be expected to require retinal laser treatment or other surgical intervention, including LRI's
  • Capsule or zonular abnormalities that may affect postoperative centration or tilt of the lens (e.g. pseudoexfoliation syndrome)
  • Pupil abnormalities (non-reactive, tonic pupils, abnormally shaped pupils, or pupils that do not dilate at least 4.0 mm under mesopic/scotopic conditions)
  • Contact lens usage within 6 months for PMMA contacts lenses, 1 month for gas permeable lenses or 1 week for extended-wear and daily-wear soft contact lens