ERG & VEP

 We are pleased to offer two new diagnostic tests to our patients. We are also pleased to receive referrals from other optometrists or medical practitioners to carry out these tests.  

 The purpose of these tests is to differentiate ocular from systemic disorders and other conditions that affect vision.  Our new visual electrophysiology diagnostic testing benefits us both for appropriate referral, co-management and treatments.

 The Diopsys® NOVA ERG and VEP Vision Testing System providesvisual electrophysiology, components of the electroencephalogram that are specific and objective measures of visual pathway function (strength and speed).   

 The Electroretinogram (ERG) measures function of the retina for ocular sequelae, results of other diseases, injury, therapy or trauma. The Visual Evoked Potential (VEP) test measures the integrity of the complete visual pathway to the visual cortex for subclinical abnormalities caused by systemic diseases and disorders. 

 Patients who would benefit most are listed below:

 1. Have special needs, difficulty taking standard vision tests (e.g. pediatric, non-verbal), or

2. May require more specific testing due to the nature of subclinical effects on  the visual pathway,  

  • Vascular diseases- systemic hypertension, diabetes mellitus, vasculitis, hematologic diseases, cerebrovascular disease, increased intracranial pressure
  • Endocrine- thyroid eye disease, metabolic storage diseases
  • Neurological-multiple sclerosis, Pupillary function, optic nerve disorders (e.g., optic nerve glioma), chiasmal tumors, myasthenia gravis, central nervous system defects or aneurysm, drug or heavy metal toxicity
  • Toxicity- hydroxychloroquine, tamoxifen, or phenothiazines,tamoxifen, or phenothiazines,  Nutritional ON, Toxic ON, drug or heavy metal toxicity
  • Infectious- acquired immunodeficiency syndrome, tuberculosis, syphilis, histoplasmosis, toxoplasmosis
  • Neoplastic- primary or metastatic tumors, orbital tumor
  • Trauma- Cerebral Oedema, compression of brain Cerebral disorder, TBI, Optic Nerve/Pathway disorder
  • Autoimmune- sarcoidosis, immune-mediated diseases