Georgios Matis

Dr. Georgios Matis

Interventional Pain Management, Spasticity and Neuromodulation Unit, Hygeia Hospital, Athens, Attikí, Greece
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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 September 2020 in Neuromodulation: Technology at the Neural Interface
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Journal Article
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PAPablo Andrade
Pablo Andrade
PHPetra Heiden
Petra Heiden
VVVeerle Visser-Vandewalle
Veerle Visser-Vandewalle
Georgios MatisGeorgios Matis
Georgios Matis
Objectives We aimed to investigate the efficacy of new subperception stimulation paradigms including 1.2 kHz‐high‐frequency stimulation (HFS) and advanced‐HFS field‐shaping algorithm (dorsal horn HFS [DHHFS]) in refractory cases which initially benefited from conventional spinal cord stimulation (SCS) and lost the effect throughout time. Materials and Methods In the context of a rescue‐therapy, patients underwent externalization of the implanted SCS‐leads and were tested with multiple combinations of new SCS paradigms. Pain intensity was analyzed using the numeric rating scale (NRS), and data were collected preoperatively and at multiple postoperative follow‐ups. Results Thirty‐seven patients underwent externalization of the leads. Mean preoperative NRS‐score was 8.1/10 points (SD ± 0.9) for the ON‐stimulation period. Patients received a combination of either tonic, burst and 1.2 kHz‐HFS, or burst and 1.2 kHz‐HFS, DHHFS, or 1.2 kHz‐HFS and DHHFS, or 1.2 kHz‐HFS alone. The mean postoperative NRS‐score after the testing‐phase was 3.8/10 points (SD ± 2.5), showing a 48.0% mean reduction (p < 0.001). In total, 29 patients reported a significant reduction above 50% in NRS‐scores and therefore were reimplanted with new generators that could deliver the new paradigms. Eight patients underwent full SCS‐system explantation. The patients who continued with the new paradigms (n = 29) reported mean NRS‐scores of 3.5/10 points (SD ± 1.7) 12 months postoperatively, still showing a significant reduction of 43.3% when compared to preoperative scores (p < 0.001). Conclusion Rescue‐therapy with combination of multiple waveforms, including tonic, burst, 1.2 kHz‐HFS, and DHHFS, was associated with a significant pain relief in patients with failed conventional SCS. This approach is a safe and efficient and should be considered before explantation of the SCS‐system.

9 March 2021 in Brain and Behavior
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Georgios MatisGeorgios Matis
Georgios Matis
PNPasquale De Negri
Pasquale De Negri
DDDenis Dupoiron
Denis Dupoiron
RLRudolf Likar
Rudolf Likar
XZXander Zuidema
Xander Zuidema
DRDirk Rasche
Dirk Rasche
This article summarizes recommendations made by six pain specialists who discussed the rationale for ziconotide intrathecal analgesia (ITA) and the requirement for evidence‐based guidance on its use, from a European perspective. Riemser Pharma GmbH (Greifswald, Germany), which holds the European marketing authorization for ziconotide, hosted the meeting. The group agreed that ITA is under‐used in Europe, adding that ziconotide ITA has potential to be a first‐line alternative to morphine; both are already first‐line options in the USA. Ziconotide ITA (initiated using a low‐dose, slow‐titration approach) is suitable for many patients with noncancer‐ or cancer‐related chronic refractory pain and no history of psychosis. Adopting ziconotide as first‐line ITA could reduce opioid usage in these patient populations. The group advocated a risk‐reduction strategy for all candidate patients, including compulsory prescreening for neuropsychosis, and requested US–European alignment of the licensed starting dose for ziconotide: the low‐and‐slow approach practiced in the USA has a better tolerability profile than the fixed high starting dose licensed in Europe. Of note, an update to the European Summary of Product Characteristics is anticipated in early 2021. The group acknowledged that the Polyanalgesic Consensus Conference (PACC) treatment algorithms for ziconotide ITA provide useful guidance, but recommendations tailored specifically for European settings are required. Before a consensus process can formally begin, the group called for additional European prospective studies to investigate ziconotide in low‐and‐slow dosing strategies, in different patient settings. Such data would enable European guidance to have the most appropriate evidence at its core.

20 November 2024 in Journal of Clinical Medicine
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SBSimon Bayerl
Simon Bayerl
JSJose F. Paz Solis
Jose F. Paz Solis
Georgios MatisGeorgios Matis
Georgios Matis
PRPhilippe Rigoard
Philippe Rigoard
JKJan Willem Kallewaard
Jan Willem Kallewaard
AWAdam Williams
Adam Williams
Background/Objectives: Over the last 20 years, spinal cord stimulation (SCS) has seen the development of various paresthesia-free paradigms. Recently, a novel modality has emerged (Fast-Acting Sub-perception Therapy, FAST) that engages the surrounding inhibition mechanism of action. We evaluated long-term, real-world outcomes of preferential FAST-SCS use in patients with chronic pain. Methods: In this multi-center, observational, consecutive case series, medical chart data from chronic pain patients preferentially using FAST-SCS (no exclusions) were retrospectively reviewed. Results: Data from 167 patients in 13 European centers were analyzed; 74% of patients suffered from persistent spine pain syndrome type 2 and 87% presented with low back and/or leg pain. At the last follow-up (mean 1.6 years), the numerical rating scale (NRS) overall pain score decreased by 5.1 ± 2.5 points versus baseline, from 8.0 ± 1.2 to 2.9 ± 2.2 (n = 167, p < 0.0001). 87% of patients reported ≥50% pain relief, and 55% were “high responders” with overall NRS pain scores ≤2/10. At the last follow-up, functional disability improved significantly (the Oswestry Disability Index reduced by 29.2 ± 21.5 points, n = 65, p < 0.0001) and patients had a significant gain in quality of life (EQ-5D-5L visual analog scale increased by 52.0 ± 26.9 points, n = 86, p < 0.0001). Results at the 2-year follow-up showed a sustained, substantial reduction in pain; 67% of patients were high responders and the NRS overall pain score decreased by 5.6 ± 2.4 versus baseline (n = 52, p < 0.0001). Conclusions: Our real-world outcomes suggest that in patients with chronic low back and/or leg pain, FAST-SCS therapy provided durable and profound pain relief and led to significant improvements in disability and quality of life.

14 February 2024 in Journal of Clinical Medicine
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PRPhilippe Rigoard
Philippe Rigoard
Maxime BillotMaxime Billot
Maxime Billot
RBRenaud Bougeard
Renaud Bougeard
JCJosé Emilio Llopis Calatayud
José Emilio Llopis Calatayud
Sylvie RaoulSylvie Raoul
Sylvie Raoul
HBHayat Belaïd
Hayat Belaïd
Spinal cord stimulation (SCS) is proven to effectively relieve chronic neuropathic pain. However, some implanted patients may face loss of efficacy (LoE) over time, and conversion to more recent devices may rescue SCS therapy. Recent SCS systems offer novel stimulation capabilities, such as temporal modulation and spatial neural targeting, and can be used to replace previous neurostimulators without changing existing leads. Our multicenter, observational, consecutive case series investigated real-world clinical outcomes in previously implanted SCS patients who were converted to a new implantable pulse generator. Data from 58 patients in seven European centers were analyzed (total follow-up 7.0 years, including 1.4 years after conversion). In the Rescue (LoE) subgroup (n = 51), the responder rate was 58.5% at the last follow-up, and overall pain scores (numerical rating scale) had decreased from 7.3 ± 1.7 with the previous SCS system to 3.5 ± 2.5 (p < 0.0001). Patients who converted for improved battery longevity (n = 7) had their pain scores sustained below 3/10 with their new neurostimulator. Waveform preferences were diverse and patient dependent (34.4% standard rate; 44.8% sub-perception modalities; 20.7% combination therapy). Our results suggest that patients who experience LoE over time may benefit from upgrading to a more versatile SCS system.

Verified
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Martina RekatsinaMartina Rekatsina
Martina Rekatsina
MLMatteo Luigi Giuseppe Leoni
Matteo Luigi Giuseppe Leoni
VVVeerle Visser-Vandewalle
Veerle Visser-Vandewalle
MMMarco Mercieri
Marco Mercieri
Giustino VarrassiGiustino Varrassi
Giustino Varrassi
Georgios MatisGeorgios Matis
Georgios Matis
Background: Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition characterized by persistent bladder-related pain and urinary symptoms, often refractory to conventional treatments. Sacral neuromodulation (SNM) has emerged as a promising therapeutic option for managing refractory IC/BPS. Methods: This retrospective study included 24 patients with IC/BPS treated with SNM between 2017 and 2022. Baseline and follow-up data were collected on pain, opioid use, urinary symptoms, and quality of life. Patients underwent a trial of tonic stimulation before permanent implantation. Continuous variables were reported as median (IQR) and categorical data as counts and percentages. Pre- and post-SNM differences were analyzed using the Wilcoxon rank-sum test. Kaplan–Meier analysis evaluated lead survival, and a Sankey diagram illustrated employment status transitions. Results: Patients had a median age of 54.5 years (IQR: 47–61), with 92% female. Subtypes included Type 1 IC/BPS (8.3%), Type 2 (45.8%), Type 3 (37.6%), and unknown type (8.3%). Median pain duration was 4.5 years (IQR: 3–7.3). SNM resulted in significant improvements in pain (NRS: baseline 8 [IQR: 8–9], last follow-up 3 [IQR: 2–4], p < 0.0001), opioid use (MME: baseline 20 [IQR: 10–40], last follow-up 0 [IQR: 0–10], p < 0.0001), urinary function (24-h voids: baseline 19 [IQR: 14.5–25.8], last follow-up 8 [IQR: 6–12], p < 0.0001), and quality of life (QOL) (EQ-5D-5L: baseline 0.50 [IQR: 0.36–0.56], last follow-up 0.83 [IQR: 0.76–0.89], p < 0.0001). Employment rates increased from 43.5% to 50%, and unemployment decreased from 8.7% to 4.2%. The median follow-up was 35 months (IQR: 28–53). Conclusions: SNM significantly improved pain, urinary symptoms, quality of life, and employment outcomes in patients with refractory IC/BPS. These findings highlight its efficacy as a minimally invasive and reversible option for managing this challenging condition.

22 December 2022 in British Journal Of Neurosurgery
Verified
Journal Article
Closed access
MOMariana De J. Oliveira
Mariana De J. Oliveira
Georgios MatisGeorgios Matis
Georgios Matis
Objectives: This review aims to analyze the last years’ experience of applying spinal cord stimulation (SCS) in complex regional pain syndrome (CRPS) patients with persistent or refractory chronic pain. Methods: This is a narrative review which was executed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and was carried out through the following databases: PUBMED and Cochrane Library. Also, a search for trials in the metaRegister of controlled trials (www.clinicaltrials.gov) was performed. Results: SCS provides pain reduction and improves sensory, vasomotor and sudomotor symptoms. It can reduce opioid using, offering better life quality for the patients. Conclusions: SCS found to be an excellent therapeutic alternative for patients with CRPS. It offers immediate pain relief and allows patients to regain functionality and have a better quality of life.