title: Correlation of pattern reversal visual evoked potential parameters with the pattern standard deviation in primary open angle glaucoma.
abstract: OBJECTIVE
  To evaluate whether glaucomatous visual field defect particularly the pattern standard deviation (PSD) of Humphrey visual field could be associated with visual evoked potential (VEP) parameters of patients having primary open angle glaucoma (POAG).
  
  
  METHODS
  Visual field by Humphrey perimetry and simultaneous recordings of pattern reversal visual evoked potential (PRVEP) were assessed in 100 patients with POAG. The stimulus configuration for VEP recordings consisted of the transient pattern reversal method in which a black and white checker board pattern was generated (full field) and displayed on VEP monitor (colour 14″) by an electronic pattern regenerator inbuilt in an evoked potential recorder (RMS EMG EP MARK II).
  
  
  RESULTS
  The results of our study indicate that there is a highly significant (P<0.001) negative correlation of P100 amplitude and a statistically significant (P<0.05) positive correlation of N70 latency, P100 latency and N155 latency with the PSD of Humphrey visual field in the subjects of POAG in various age groups as evaluated by Student's t-test.
  
  
  CONCLUSIONS
  Prolongation of VEP latencies were mirrored by a corresponding increase of PSD values. Conversely, as PSD increases the magnitude of VEP excursions were found to be diminished.
authors.affiliation: Department of Physiology, MGIMS, Sevagram, Wardha, Maharashtra 442102, India.
authors.forename: Ruchi
authors.initials: R
authors.lastname: Kothari
authors.affiliation: Department of Anatomy, MGIMS, Sevagram, Wardha, Maharashtra 442102, India.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Bokariya
authors.affiliation: Department of Physiology, AIIMS, Patna, Bihar 801105, India.
authors.forename: Ramji
authors.initials: R
authors.lastname: Singh
authors.affiliation: Department of Ophthalmology, MGIMS, Sevagram,Wardha, Maharashtra 442102, India.
authors.forename: Smita
authors.initials: S
authors.lastname: Singh
authors.affiliation: Department of Ophthalmology, MGIMS, Sevagram,Wardha, Maharashtra 442102, India.
authors.forename: Purvasha
authors.initials: P
authors.lastname: Narang
keywords: P100 latency; pattern reversal; pattern standard deviation; visual field