Exploring retinal thickness variations in adolescents with first episode psychosis and schizophrenia: A comparative...

The retina offers a way to indirectly evaluate inflammation and degeneration in the brain. Recently, scientists are focusing on the retina as a valuable tool to understand brain structure and function. This study aims to compare retinal layer thicknesses of adolescents by using Optical coherence tomography (OCT), between first episode psychosis and schizophrenia patients, healthy siblings of schizophrenia patients and healthy control groups.

The study included 18 first episode psychosis (FEP) and 22 schizophrenia patients, 29 healthy siblings of schizophrenia patients and 31 healthy controls.The sociodemographic data form, Scale for the Assesment of Negative Symptoms(SANS), Scale for the Assessment of Positive Symptoms (SAPS), Clinical Global Impression (CGI) scale were completed by the clinician. The total macular thickness, macular retinal nerve fiber layer (RNFL), inner retinal layers including, ganglion cell layer (GCL), inner plexiform layer (IPL) were automatically measured by using OCT and compared between the four groups.

The inner süperior and inner inferior subsegments of IPL and inner temporal subsegments of GCL were found thinner in schizophrenia patients and healthy siblings than healthy controls. Also, average GCL, inner süperior, inner nasal of RNFL thickness was greater in FEP patients than in healthy siblings and controls.

Retinal thinning in schizophrenia patients and healthy siblings might be the result of the neurodegeneration seen at schizophrenia. Also thinning in healthy siblings might be an endophenotype candidate. And the thickening in the FEP group could be due to neuroinflammation and edema occurring in the acute phase of the illness.