Publications by authors named "George Tagaris"

Introduction: Conventional care in Parkinson's disease (PD) faces limitations due to the significant time and location commitments needed for regular assessments, lacking quantitative measurements. Telemonitoring offers clinicians an opportunity to evaluate patient symptomatology throughout the day during activities of daily living.

Methods: The progression of PD symptoms over a two-year period was investigated in patients undergoing traditional evaluation, supplemented by insights from ambulatory measurements.

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Aim: To evaluate the alterations of the retinal microvasculature and foveal avascular zone in patients with Parkinson's disease (PD) using optical coherence tomography angiography (OCT-A).

Methods: A retrospective study of PD patients examined in the Ophthalmology Department of the General Hospital of Athens, "Georgios Gennimatas" from March 2021 to March 2022 was conducted. Totally 44 patients with PD were included and 18 healthy controls were examined, hence a total of 124 eyes were enrolled in the study.

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The combination of a tibial tubercle fracture with patellar tendon avulsion in adolescents is an extremely rare injury that needs to be managed properly. Herein, we report the case of a 15-year-old boy who presented to our department two months after sustaining a tibial tubercle fracture that had been managed with mini-open reduction and internal fixation in another hospital; he had restricted range of motion and complete inability to extend his knee. Clinical and radiological investigations revealed a neglected avulsion of the patellar tendon with marked scarring and severe retraction.

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Purpose: Proximal tibial metaphyseal fractures can be complicated by a late valgus deformity, referred to as Cozen's phenomenon. We studied children with such fractures to determine whether the child's age at the time of injury influenced the development of Cozen's as well as the occurrence of elongation. In addition, we explored whether the deformity resolved at long-term follow-up.

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Capitellum fractures represent 1% of elbow fractures. A coronal shear fracture which involves the trochlea is classified as a type IV McKee fracture. The combination of its rarity in the paediatric population as well as its unique appearance on X-ray make diagnosis of this fracture a challenge.

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Objective: The aim of this study was to evaluate the degree of brain tissue injury that could be potentially induced by the introduction of a) microrecording electrodes, b) macrostimulation electrodes, or c) chronic stimulation electrodes. We aimed to evaluate whether the use of five simultaneous microrecording tracks is associated with any brain injury not detectable by conventional imaging such as CT or MRI.

Materials And Methods: The study included 61 patients who underwent surgery for implantation of 121 DBS leads.

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Advances in the field of closed-loop neuromodulation call for analysis and modeling approaches capable of confronting challenges related to the complex neuronal response to stimulation and the presence of strong internal and measurement noise in neural recordings. Here we elaborate on the algorithmic aspects of a noise-resistant closed-loop subthalamic nucleus deep brain stimulation system for advanced Parkinson's disease and treatment-refractory obsessive-compulsive disorder, ensuring remarkable performance in terms of both efficiency and selectivity of stimulation, as well as in terms of computational speed. First, we propose an efficient method drawn from dynamical systems theory, for the reliable assessment of significant nonlinear coupling between beta and high-frequency subthalamic neuronal activity, as a biomarker for feedback control.

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Objective: Almost 30 years after the start of the modern era of deep brain stimulation (DBS), the subthalamic nucleus (STN) still constitutes a standard stimulation target for advanced Parkinson's disease (PD), but the use of STN-DBS is also now supported by level I clinical evidence for treatment-refractory obsessive-compulsive disorder (OCD). Disruption of neural synchronization in the STN has been suggested as one of the possible mechanisms of action of standard and alternative patterns of STN-DBS at a local level. Meanwhile, recent experimental and computational modeling evidence has signified the efficiency of alternative patterns of stimulation; however, no indications exist for treatment-refractory OCD.

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Objective: During deep brain stimulation (DBS) surgery for the treatment of advanced Parkinson's disease (PD), microelectrode recording (MER) in conjunction with functional stimulation techniques are commonly applied for accurate electrode implantation. However, the development of automatic methods for clinical decision making has to date been characterized by the absence of a robust single-biomarker approach. Moreover, it has only been restricted to the framework of MER without encompassing intraoperative macrostimulation.

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The authors report on 2 young patients who developed drug-resistant idiopathic dystonic camptocormia (bent spine) and were treated successfully by deep brain stimulation (DBS) of the globus pallidus internus (GPi). The first patient, a 26-year-old woman, suffered for 3 years from such severe camptocormia that she became unable to walk and was confined to bed or a wheelchair. The second patient, a 21-year-old man, suffered for 6 months from less severe camptocormia; he was able to walk but only for short distances with a very bent spine, the arms in a parallel position to the legs, and the hands almost approaching the floor to potentially support him in case of a forward fall.

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Recordings from the basal ganglia's subthalamic nucleus are acquired via microelectrodes immediately prior to the application of Deep Brain Stimulation (DBS) treatment for Parkinson's Disease (PD) to assist in the selection of the final point for the implantation of the DBS electrode. The acquired recordings reveal a persistent characteristic beta band peak in the power spectral density function of the Local Field Potential (LFP) signals. This peak is considered to lie at the core of the causality-effect relationships of the parkinsonian pathophysiology.

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The present study demonstrates a new experimental model to compare the efficacy of end-to-end and end-to-end neurorrhaphy in free muscle flap neurotization. Forty animals were used, divided into four equal groups named A, B, C and D. The peripheral stump of the thoracodorsal nerve was stitched end-to-end in groups A and C and end-to-side in groups B and D to the long thoracic nerve.

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This study investigated the effect of local administration of nerve growth factor-7S (NGF-7S) on the axonal regrowth of mixed peripheral nerves through inside-out vein grafts. Sixty male Wistar rats were randomized into two groups (n = 30). A defect 12 mm long in the right sciatic nerve was created and repaired with an inside-out vein graft from the right jugular vein.

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