Retinal and Choroidal Changes in Patients with Parkinson's Disease Detected by Swept-Source Optical Coherence Tomography

Purpose: To evaluate the ability of new Swept source (SS) optical coherence tomography (OCT) technology to detect changes in retinal and choroidal thickness in patients with Parkinson's disease (PD). Design: Observational case-control cross sectional study, developed from January to May 2016. Methods: In total, 50 eyes from 50 patients diagnosed with PD and 54 eyes of 54 healthy controls underwent retinal and choroidal assessment using SS DRI Triton OCT (Topcon), using the 3D Wide protocol. Total macular thickness and peripapillary data (retinal, ganglion cell layer [GCL+, GCL++] and retinal nerve fiber layer [RNFL] thickness) were analyzed. Macular and peripapillary choroidal thickness was evaluated (Figure 1). Results: Significant peripapillary retinal thinning was observed in PD patients in total average (p = 0.017), in the nasal (p = 0.038) and temporal (p = 0.004) quadrants and in superotemporal (p = 0.004), nasal (p = 0.039), inferotemporal (p = 0.019), and temporal (p = 0.003) sectors. RNFL and GCL ++ thickness showed a significant reduction in the inferotemporal sector (p = 0.026 and 0.009, respectively). No differences were observed in macular retinal thickness between controls and patients. Choroidal thickness was found to have increased in all sectors in PD patients compared with controls, both in the macular (inner nasal, p = 0.015; inner inferior, p = 0.030; outer nasal, p = 0.012; outer inferior, p = 0.049) and the peripapillary area (total thickness, p = 0.011; nasal, p = 0.025; inferior, p = 0.007; temporal, p = 0.003; inferotemporal, p = 0.003; inferonasal, p = 0.016) Conclusion: New SS technology for OCT devices detects retinal thinning in PD patients, providing increased depth analysis of the choroid in these patients. The choroid in PD may present increased thickness compared to healthy individuals; however, more studies and histological analysis are needed to corroborate our findings.