CME With Different Fluidic Parameters

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Abhay R. Vasavada, Iladevi Cataract and IOL Research Center
ClinicalTrials.gov Identifier:
NCT01385852
First received: June 28, 2011
Last updated: June 5, 2012
Last verified: June 2012
  Purpose

Understanding and modulating fluid parameters is an important, but often overlooked aspect of phacoemulsification. In a previous study we compared the impact of using high fluid parameters versus low fluidic parameters on real-time IOP measured during phacoemulsification. The investigators found that using high parameters resulted in a higher absolute rise in IOP as well as higher fluctuations in the IOP when compared to low parameters. Clinically these higher fluctuations in IOP would translate in a higher chamber instability. Based on the results of this study, the investigators decided to take it further and study the impact of using high parameters (and thus, higher chamber instability) on macular edema and thickness following surgery, in an otherwise uncomplicated surgery.

Higher fluid parameters during phacoemulsification predisposes the eye to increased macular thickness


Condition Intervention Phase
Cystoid Macular Edema Following Cataract Surgery
Procedure: microcoaxial phacoemulsification
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Impact of Different Fluidic Parameters on Development of Cystoid Macular Edema Following Phacoemulsification

Resource links provided by NLM:


Further study details as provided by Iladevi Cataract and IOL Research Center:

Primary Outcome Measures:
  • cystoid macular edema (CME) [ Time Frame: 3 months ] [ Designated as safety issue: Yes ]
    A > or = 30% increase in baseline central foveal thickness measaured by anterior segment OCT will be defined as having CME.


Secondary Outcome Measures:
  • macular thickness [ Time Frame: 1, 3 months ] [ Designated as safety issue: Yes ]
    macular thickness measured in 3 zones using the anterior segment OCT

  • central corneal thickness (CCT) [ Time Frame: first post-operative day, ] [ Designated as safety issue: Yes ]
    CCT will be measured on the ultrasound pachymeter by a single experienced observer

  • endothelial cell loss [ Time Frame: 6 months post-operative ] [ Designated as safety issue: Yes ]
    Endothelial cell loss will be measured using a specular microscope in the central area by a single technician

  • anterior chamber inflammation [ Time Frame: 1 months ] [ Designated as safety issue: Yes ]
    it will be assessed on the slit lamp examination by a single experienced observer using the Hogan's criteria

  • CORRECTED DISTANCE VISUAL ACUITY (CDVA) [ Time Frame: 3 months ] [ Designated as safety issue: Yes ]
    visual acuity (VA) of 20/40 or worse was defined as "clinically significant"


Enrollment: 150
Study Start Date: May 2010
Study Completion Date: August 2011
Primary Completion Date: February 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Longitudinal U/S - low fluidic
ASPIRATION FLOW RATE - 25 CC/MIN, BOTTLE HEIGHT - 90 CMS, LONGITUDINAL ULTRASOUND
Procedure: microcoaxial phacoemulsification
conventional longitudinal ultrasound
Other Names:
  • phacoemulsification
  • small incision cataract surgery
Active Comparator: Torsional U/S - low fluidic
ASPIRATION FLOW RATE - 25 CC/MIN, BOTTLE HEIGHT - 90 CMS, TORSIONAL ULTRASOUND
Procedure: microcoaxial phacoemulsification
conventional longitudinal ultrasound
Other Names:
  • phacoemulsification
  • small incision cataract surgery
Active Comparator: Longitudinal U/S - high fluidic
ASPIRATION FLOW RATE - 40 CC/MIN, BOTTLE HEIGHT - 110 CMS, LONGITUDINAL ULTRASOUND
Procedure: microcoaxial phacoemulsification
conventional longitudinal ultrasound
Other Names:
  • phacoemulsification
  • small incision cataract surgery

Detailed Description:

Several studies have shown the adverse impact of an increase in the IOP and IOP fluctuations that occur during anterior segment intervention on the posterior segment structures. In human volunteers with each incremental increase in IOP the systolic and diastolic flow velocities in the short posterior ciliary arteries decreased linearly. This implies that the normal healthy eye is not able to autoregulate to maintain posterior ciliary artery blood flow velocities in response to acute large elevations in IOP. Vascular insufficiency due to abnormal autoregulation has been proposed as a major factor in the development of glaucoma. 1

It has been postulated that IOP elevation during the LASIK procedure causes mechanical stress which may induce tangential stress on the posterior segment.2, 3 Some studies have reported that the increase in IOP damages the retinal ganglion cells causing visual field defects. Also sudden increases in IOP, although well tolerated may induce changes in the peripheral retina.4,5,6

Several reports propose the occurrence of macular hole, lacquer cracks and choroidal neovascular membranes following the LASIK procedure. 3 It has been observed that the rapidly fluctuating pressure variations may be detrimental, particularly in susceptible persons with compromised ocular blood flow. Rapid IOP changes across a 30-mm Hg range would be predicted to influence posterior segment blood vessels.

In a previous study we compared the impact of using high fluid parameters versus low fluidic parameters on real-time IOP measured during phacoemulsification. We found that using high parameters resulted in a higher absolute rise in IOP as well as higher fluctuations in the IOP when compared to low parameters. Clinically these higher fluctuations in IOP would translate in a higher chamber instability.

We hypothesize that although transient, the increased IOP that occurs during phacoemulsification when using high parameters could cause mechanical stress on the eye. These higher fluid parameters during phacoemulsification can predispose the eye to increased macular thickness.

To the best of our knowledge there are no published data on impact of IOP changes and fluctuation that are induced during cataract surgery on the macula. To investigate this further, we decided to study the impact of using high parameters (and thus, higher chamber instability) on macular thickness following surgery, in an otherwise uncomplicated surgery.

  Eligibility

Ages Eligible for Study:   40 Years to 70 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  1. Uncomplicated, Age-related cataract.
  2. Nuclear sclerosis: upto grade 3
  3. Age: 40-70 years
  4. Axial length: 21.5 mm to 24.5 mm

Exclusion Criteria:

  1. Diabetes mellitus
  2. Co-existing ocular disease- uveitis, glaucoma, PEX
  3. Pre-existing macular pathology (eg.ARMD)
  4. Previously operated eyes
  5. Under treatment with Topical or systemic steroids / NSAID's
  6. Intraoperative complications- PCR, Descemet's detachment, uveal trauma
  7. Post operative complications - severe inflammation (>grade 3), rise in IOP
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01385852

Locations
India
Raghudeep Eye Clinic
Ahmedabad, Gujarat, India, 380013
Sponsors and Collaborators
Iladevi Cataract and IOL Research Center
Investigators
Principal Investigator: ABHAY R VASAVADA, MS, FRCS ILADEVI CATARACT AND RESEARCH CENTER
  More Information

Additional Information:
Publications:
Responsible Party: Abhay R. Vasavada, principal investigator, Iladevi Cataract and IOL Research Center
ClinicalTrials.gov Identifier: NCT01385852     History of Changes
Other Study ID Numbers: 10-005
Study First Received: June 28, 2011
Last Updated: June 5, 2012
Health Authority: India: Institutional Review Board

Keywords provided by Iladevi Cataract and IOL Research Center:
CME
OCT
Optical coherence tomography
macular thickness

Additional relevant MeSH terms:
Edema
Macular Edema
Cataract
Signs and Symptoms
Macular Degeneration
Retinal Degeneration
Retinal Diseases
Eye Diseases
Lens Diseases

ClinicalTrials.gov processed this record on July 22, 2014