Table 1. Electroretinography (ERG) research in psychiatric patients.
| Authors | Year | Patients | Healthy subjects | Mean age (yrs) | Medication | Comorbidities that cause retinal changes | PANSS | Results |
|---|---|---|---|---|---|---|---|---|
| Warner et al. (8) | 1999 | 9 (Sch) | 9 | / | Chlorpromazine or none | / | / | Decreased a-wave amplitudes in photopic and scotopic conditions in patients regardless of medication |
| Gerbaldo et al. (11) | 1992 | 9 (Sch) | 13 | 37.5 | Haloperidol | / | / | Decreased b-wave amplitudes in ‘photophilic’ Sch group (n=6) during scotopic testing |
| Holopigian et al. (12) | 1994 | / | 19 | 26.7 | Chlorpromazine, Fluphenazine Metoclopramide | / | / | Decreased b-wave amplitudes while on chlorpromazine and fluphenazine medication, but without changes while using metoclopramide in scotopic and photopic flicker tests |
| Balogh et al. (13) | 2008 | 26 (Sch) 17 (BAD) |
20 | 38.2 | Sch: olanzapine, risperidone, quetiapine, clozapine, BAD: olanzapine, valproate, lithium, clonazepam, citalopram |
/ | Yes | Patients with Sch in the acute stage showed decreased a-wave amplitudes (in correlation with positive symptoms) using flash ERG testing, while participants with bipolar disorder did not show ERG anomalies |
| Hébert et al. (14, 15) | 2010 | 29 (Sch and BAD) | 29 | 20.7 | / | / | / | Decreased b-wave amplitudes in participants at a high risk of developing Sch and BAD, tested in scotopic conditions |
| Demmin et al. (16) | 2018 | 25 (Sch) | 25 | Antipsychotics | Excluded | Yes | Correlation of negative symptoms and decrease in a-wave amplitude on photopic testing (PPhNR) and correlation of excitement with longer b-wave implicit time in scotopic conditions (S2) |
ERG= electroretinography; yrs = years; PANSS = Positive and Negative Syndrome Scale questionnaire; Sch = schizophrenia; BAD = bipolar affective disorder; PPhNR = photopic testing