Table 2. Optical coherence tomography (OCT) research in patients with schizophrenia.
| Authors | Year | Patients | Healthy participants | Mean age (yrs) | Medication | Comorbidities that can cause retinal changes | PANSS | Results |
|---|---|---|---|---|---|---|---|---|
| Chu et al. (23) | 2012 | 38 (Sch) 11 (schizo-affective disorder) |
49 | 29.7 | 40 used antipsychotics, 4 used mood stabilizers + antipsychotics, 2 used mood stabilizers, 1 used nocturnal sedation, 5 non-medicated | Excluded | / | Thinning of RNFL in all patients Patients with schizoaffective disorder had thinner RNFL in right nasal quadrant compared to patients with schizophrenia |
| Samani et al. (24) | 2017 | 35 (Sch) | 50 | 40.6 | Antipsychotics | / | Yes | Patients showed thinning of photoreceptor complex in all regions, thinning of outer plexiform layer and inner segmented layer Decreased contrast sensitivity correlated with thinning of temporal parafoveal complex of ganglion cells The severity of negative symptoms was negatively related to thickness of foveal photoreceptor complex and outer plexiform layer |
| Ascaso et al. (25) | 2015 | 20 (NRIE) (Sch) 10 (RIE) (Sch) |
30 | 44.8 | Antipsychotics | Excluded | Yes | All patients showed thinning of peripapillary RNFL in all quadrants of both eyes Macular thickness and macular volume were also decreased in all patients in both eyes Decreased macular inner ring, foveal thickness and macular volume in the left eye were statistically significant |
| Lee et al. (29) | 2013 | 30 (Sch) | 30 | 35.07 | Antipsychotics | Excluded | Yes | Thinning of RNFL in the peripapillary area of the retina in superior, inferior and temporal quadrants in patients Thinning of the central part of the macula, inner and outer macular ring, as well as macular volume decrease were found in patients The amount of RNFL thinning and decrease of macular volume correlated with disease duration |
| Yilmaz et al. (32) | 2015 | 34 (Sch) | 30 | 39.22 | / | Excluded | / | Thinning of RNFL in patients in all quadrants Macular thickness in nasal quadrant and inferior outer quadrant was also significantly thinner |
| Silverstein et al. (33) | 2018 | 32 (Sch) | 32 | 40.9 | Antipsychotics | / | Yes | The patient group showed enlarged cup volume and enlarged cup-to-disc ratio in both eyes These findings were unrelated to medical comorbidity and were related to cognitive symptoms |
OCT = optical coherence tomography; yrs = years; PANSS = Positive and Negative Syndrome Scale questionnaire; Sch = schizophrenia; RIE = recent illness episode; NRIE = non-recent illness episode; RNFL = retinal nerve fiber layer