Protective Effect of Phenytoin on Glaucoma

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00739154
Recruitment Status : Unknown
Verified August 2008 by Rabin Medical Center.
Recruitment status was:  Not yet recruiting
First Posted : August 21, 2008
Last Update Posted : August 21, 2008
Information provided by:
Rabin Medical Center

August 20, 2008
August 21, 2008
August 21, 2008
November 2008
November 2010   (Final data collection date for primary outcome measure)
peripapillary RNFL thickness [ Time Frame: immediate ]
Same as current
No Changes Posted
corrected pattern standard deviation in perimetric visual field [ Time Frame: immediate ]
Same as current
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Protective Effect of Phenytoin on Glaucoma
Clinical Cohort Study of Association Between Steady State Phenytoin Treatment and Better Clinical Parameters of Glaucoma

since glaucoma is considered an optic neuropathy, new treatments for glaucoma are being continuously investigated, including neuroprotection.

Previous studies implied that phenytoin, a potent anti-convulsive drug, has a neuroprotective role, and Na+ channels blockage was suggested as a possible mechanism.

This study predicts that glaucoma patients taking Phenytoin will have a less advanced glaucoma as compared to patients not taking the drug. Glaucoma severity will be determined by visual acuity, visual fields, optic disc cupping and nerve fiber layer thickness

The study will examine adult patients who suffer from glaucoma and epileptic disorders on the same time. the study group will include glaucoma patients, being treated with oral Phenytoin for their epileptic disorder. The study group will be compared to 2 control groups:

  • Glaucoma patients with epileptic disorder,receiving different medication than Phenytoin
  • Glaucoma patients with no epileptic disorder.

    4 parameters will be evaluated for all groups:

    1. Best corrected visual acuity
    2. Optic disc cupping
    3. visual fields and general perimetric indices
    4. peripapillary retinal nerve fiber layer.

Every participant in the study,after giving his informed consent, will be evaluated by a senior ophthalmologist in a single office appointment. The appointment will include a visual acuity, complete ophthalmic examination,Humphrey perimetric visual field testing and peripapillary RNFL thickness measurement by OCT.

no drug or other treatment will be given to the participants

after data collection, average +/-Standard deviation for the 4 parameters will be compared between the 3 groups. Student T-test and one- way ANOVA will be used for statistical analysis.

Observational Model: Cohort
Time Perspective: Cross-Sectional
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Non-Probability Sample
patients of a tertiary hospital's specialized epilepsy clinic
  • Primary Open Angle Glaucoma
  • Secondary Open Angle Glaucoma
  • Narrow-Angle Glaucomas
  • Normal Tension Glaucoma
Not Provided
  • 1
    glaucoma patients who also suffer from epileptic disorder and receiving chronic oral Phenytoin treatment
  • 2
    glaucoma patients who also suffer from epileptic disorder receiving anti-convulsant treatment other then Phenytoin
  • 3
    glaucoma patients with no epileptic disorder and not receiving anti-convulsant treatment

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Unknown status
Same as current
December 2010
November 2010   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Clinical diagnosis of glaucoma
  • chronic treatment with phenytoin for any indication

Exclusion Criteria:

  • pregnancy
  • visual acuity less then 6/60
Sexes Eligible for Study: All
18 Years and older   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
Not Provided
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prof. Dov Weinberger, head of ophthalmology department, Rabin medical center
Rabin Medical Center
Not Provided
Study Director: Omer Y Bialer, MD Rabin medical center, Petah Tikva, Israel
Study Director: Dan Gaa'ton, MD Rabin medical center, Petah-Tikva, Israel
Rabin Medical Center
August 2008