title: Unwrapping of transient responses from high rate overlapping pattern electroretinograms by deconvolution.
abstract: OBJECTIVE
  Due to overlapping, temporal information is mostly lost in high rate steady-state pattern electroretinograms (PERGSS). This study develops a deconvolution method and a display/recording system to "unwrap" PERGSS and obtain a transient, "per stimulus" response (PERGtr) regardless of reversal rate.
  
  
  METHODS
  Processing and instrumentation, including high temporal resolution display and acquisition were developed for deconvolving PERGs acquired at high rates by slight jittering of reversal onsets at a given mean rate.
  
  
  RESULTS
  The system was successfully tested at eight rates from 2.2 to 78.1rps. At medium rates (17.4-41.2rps) recordings with conventional morphology (N35-P50-N95) but earlier peaks and higher amplitudes were extracted up to 40rps. At higher rates, smaller triphasic responses were obtained, exhibiting similar peak latencies, but reversed polarity. Oscillating potentials (OPs) were also recorded at all rates after deconvolution.
  
  
  CONCLUSIONS
  Transient PERGs and OPs can be extracted from quasi steady-state PERG recordings obtained at high rates with a deconvolution algorithm using high temporal resolution display and acquisition systems.
  
  
  CONCLUSIONS
  The methodology to extract transient and oscillatory responses from steady-state PERGs could be useful in understanding high rate responses and diagnosis of various retinal diseases by revealing temporal information on waveform components which cannot be normally observed.
authors.affiliation: University of Miami, Dept. Biomedical Engineering, PO Box 248294, Coral Gables, FL 33124, United States; JÖRVEC Corp., Miami, FL, 6860 SW 81 St, Miami, FL 33143, United States.
authors.forename: Jonathon
authors.initials: J
authors.lastname: Toft-Nielsen
authors.affiliation: University of Miami, Dept. Biomedical Engineering, PO Box 248294, Coral Gables, FL 33124, United States.
authors.forename: Jorge
authors.initials: J
authors.lastname: Bohórquez
authors.affiliation: University of Miami, Dept. Biomedical Engineering, PO Box 248294, Coral Gables, FL 33124, United States; University of Miami, Depts. Otolaryngology, Pediatrics and Neuroscience (Graduate), United States. Electronic address: oozdamar@miami.edu.
authors.forename: Özcan
authors.initials: Ö
authors.lastname: Özdamar
mesh_terms: D000328:Adult; D004568:Electrodiagnosis / Q000295:instrumentation / Q000379:methods*; D004596:Electroretinography / Q000295:instrumentation / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D055815:Young Adult
keywords: Deconvolution; High rate electroretinography; Oscillatory responses; Pattern electroretinogram; Steady-state PERGs; Unwrapping