Evaluati̇on The Change Of Corneal Parameters By Scheimpflug Imaging In Parkinson's Disease After Deep Brain Stimulation While The Device Is “Stimulation On” Mode
Published 2026 - 44th Congress of the ESCRS
Reference: POANT009 | Type: Free paper | DOI: 10.82333/spg1-q480
Authors: Dr Ebru Comert Hamzaoğlu* 1 , A/Prof. Erman Bozali 1
1Ophthalmology,Mersin City Traning and Research Hospital,Mersin,Türkiye
Purpose
Parkinson's disease (PD) is a long-term disease caused by the progressive degeneration of dopaminergic neurons in substantia nigra. The ocular and oculomotor findings are quite common in patients with parkinsonism.Today, the most modern and feasible treatment option for idiopatic PD, is targeting specific nuclei for neuromodulation, also known as deep brain stimulation (DBS), in which an implantable ‘neuropacemaker’ of high‐frequency electric current through electrodes permanently implanted into distinct nodes of the basal ganglia's (BG) motor circuitries. The purpose of this study was to investigate the change of corneal parameters by Scheimpflug imaging at 4 month follow- up of DBS, while the device is “stimulation on” mode.
Setting
This retrospective study was conducted at the Ophthalmology Department of Mersin City Training and Research Hospital, Turkey. Datas of patients who had DBS for PD between January 2025 and December 2025, were extracted from electronic medical records in accordance with predefined criteria. The study protocol was approved by the Ethics Committee of Mersin University.
Methods
A total of 28 patients who underwent DBS surgery for advanced PD with preoperative and postoperative 4th month pachmetry and keratometry datas (K1, K2, Kmax),measured using a Scheimpflug camera (Pentacam HR; Oculus GmbH, Wetzlar, Germany), were included the study.At the 4 month follow-up, all patients had their devices in the “stimulation on” mode for at least three months.We accepted the right eye’s datas of all patients for the statistical analysis. The exclusion criterias for the study were corneal pathology, dense media opacities, history of uveitis, glaucoma, ocular trauma and intraocular surgery. Moreover, a history of systemic disease, such as hypertension or diabetes mellitus also resulted in patients being excluded from the study.
Results
Preoperative and 4-month postoperative measurements were analyzed using the paired samples t-test. The mean K1 value was 42.29 ± 1.21 preoperatively and 42.26 ± 1.18 at 4 month follow-up (p = 0.620), while the mean K2 values were 43.17 ± 1.23 and 43.18 ± 1.24, respectively (p = 0.849). The mean Kmax changed from 44.13 ± 1.23 to 44.02 ± 1.32 (p = 0.130), the mean central corneal thickness decreased from 545.08 ± 46.36 to 540.31 ± 44.14 (p = 0.258) and the mean K changed from 42.61 ± 1.26 to 42.76 ± 1.21 (p = 0.251), postoperatively. No statistically significant differences were observed between preoperative and 4-month postoperative measurements for any of the evaluated parameters (all p > 0.05).
Conclusions
Deep brain stimulation allows the implanted pulse generator to be switched on or off, potentially affecting blink rate and ocular surface stability. Parkinson’s disease is associated with reduced spontaneous blinking and altered ocular surface homeostasis, raising the possibility that stimulation settings could influence corneal parameters. In this study, keratometric values did not differ between the “on” and “off” states, indicating that active DBS does not compromise corneal parameters used for clinical purposes such as intraocular lens calculation. Long-term follow-up is warranted to determine whether chronic stimulation may exert subtle effects on corneal morphology over time.