Retinal nerve fiber layer decrease and choroidal layer increase after four weeks of buprenorphine/naloxone maintenance treatment in opioid use disorder

Background and Objectives: Spectral-domain optical coherence tomography (SD-OCT) findings in substance use disorders have been investigated in recent years. In this study, we compared the retinal nerve fiber layer (RNFL), the ganglion cell layer (GCL), the inner plexiform layer (IPL), and the choroid thickness (CT) of OUD and control groups before and after buprenorphine/naloxone maintenance treatment (BN-MT).MethodsThe OUD group consisted of 46 male subjects and the control group consisted of 49 male subjects. Patients with chronic opioid use and opioid positivity in their urine during the initial SD-OCT application were included in the study. At the end of the fourth week of BN-MT, SD-OCT was repeated and BN positivity was detected in the urine of the patients at this time.ResultsThere was a significant difference between OUD and control groups in terms of nasal superior and CT values of both eyes (p<0.05) before BN use. The values of RNFL sectors and CT of both eyes before and after BN-MT differed significantly (p<0.05); CT increased and RNFL sectors decreased. After BN-MT, psychometric scales differed significantly in favor of the patients (p<0.05). The SD-OCT values of the OUD group after BN-MT were compared with the control group: the right IPL (p=0.003), the left IPL (p=0.023), the right N (p=0.001) and the left N (p<0.001) values were significantly lower in the OUD group.ConclusionThis is the first study to show the SD-OCT findings of patients with OUD before and after BN-MT. The findings of this study may indicate possible effects of chronic opioid use in patients and/or possible effects of exogenous opioid or BN present in the body during SD-OCT applications. However, based on our findings, it is not possible to distinguish between the two possible outcomes. The fact that the use of BN acting through opioid receptors has different effects from exogenous opioids may be due to different receptor profiles. (AU)

Optic coherence tomography shows inflammation and degeneration in major depressive disorder patients correlated with disease severity.

BACKGROUND: Previous research has consistently detected inflammation in the etiology of depression and neuroimaging studies have demonstrated gray matter abnormalities implying a neurodegenerative process in depression. The aim of this study was to compare ganglion cell layer (GCL), and inner plexiform layer (IPL) volumes and retinal nerve fiber layer (RNFL) thickness between first episode and recurrent major depressive disorder (MDD) patients and controls using optic coherence tomography (OCT) in order to detect findings supporting a degenerative process. Also choroid thicknesses of the same groups were compared to examine effects of inflammation on MDD. METHODS: This study included 50 recurrent MDD patients, 50 first episode MDD patients and 50 controls. OCT measurements were performed by a spectral OCT device. GCL and IPL volumes and RNFL and choroid thicknesses were measured automatically by the device. RESULTS: GCL and IPL volumes were significantly smaller in recurrent depression patients than first episode patients and in all MDD patients than controls. Also there were significant negative correlations between their volumes and disease severity parameters such as Ham-D and CGI scores, and disease duration. RNFL thicknesses were also lower in recurrent MDD patients than first episode patients and all MDD patients than controls but statistical significance was achieved only for global RNFL and temporal superior RNFL. Mean choroid thickness was higher in MDD patients than controls and in first episode MDD patients than recurrent MDD patients. LIMITATIONS: Cross-sectional design of our study limits conclusions about progressive degeneration during the course of MDD. Lack of a control neuroimaging method like magnetic resonance imaging makes it hard to draw firm conclusions from our results. CONCLUSIONS: OCT finding of decreased GCL and IPL volumes supports previous research suggesting degeneration in MDD. OCT may be an important tool to track neurodegeneration in patients with major depression. Considering RNFL to be the latest layer that will be affected during course of degeneration, GCL and IPL volumes appear to be better parameters to follow. In addition, choroid may be an important structure to detect acute attack period and to follow inflammatory process in MDD like in systemic inflammatory diseases.

Can the retinal ganglion cell layer (GCL) volume be a new marker to detect neurodegeneration in bipolar disorder?

PURPOSE: The aim of this study was to compare the ganglion cell layer (GCL) volume and retinal nerve fiber layer (RNFL) thickness in bipolar patients and controls using optic coherence tomography to demonstrate neurodegeneration in bipolar disorder. METHODS: This study involved 43 euthymic bipolar I patients who were being followed by the Psychiatry Department of Adiyaman University Medical School and 43 healthy volunteers as controls. Optic coherence tomography (OCT) measurements were performed for both groups. The RNFL thickness and GCL volumes were measured and recorded automatically by a spectral OCT device. FINDINGS: No differences in sociodemographics were detected between groups, except for unemployment status, which was significantly higher in the patient group. The RNFL thickness was lower in patients compared with controls at all measured regions, and this decrease was statistically significant for the global RNFL measurement. The GCL volume was also significantly lower in the patient group. There was a significant negative correlation between the disease parameters, such as the disease duration, YMRS score, CGI score, and number of hospitalizations, and GCL volume. DISCUSSION: These findings suggest that neurodegeneration occurs during the course of bipolar disorder. This degeneration may be demonstrated by decreased GCL at early stages, and as the disease progresses, involvement of other retinal layers, such as the RNFL and IPL, may be observed.