Alexis Kelekis
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Interests
Alexis Kelekis has a total of 514 co-authors. Here are the top co-authors by number of shared publications:
- Dimitrios Filippiadis
Second Department of Radiology, University General Hospital Attikon, Athens, Greece
55 shared publications - Nikolaos Kelekis
2nd Department of Radiology, University General Hospital “ATTIKON”, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
31 shared publications - Georgios Velonakis
Research Unit of Radiology and Medical Imaging, National and Kapodistrian University of Athens, Athens, Greece
14 shared publications - Argyro Mazioti
2nd Department of Radiology, University General Hospital “Attikon”, National and Kapodistrian University of Athens, 12462 Athens, Greece
9 shared publications Dimitrios Filippiadis
National and Kapodistrian University of Athens, School of Medicine
9 shared publicationsElias Brountzos
Second Department of Radiology, School of Medicine, National and Kapodistrian University of Athens, 'Attikon' University General Hospital, Athens, Greece
9 shared publications
Latest Publications
- Open Access
- 11 June 2025
- Published by Springer Nature in Osteoporosis International
- Vol. 36 (8) , 1297-1311
Risk factors for refracture or new vertebral compression fractures after percutaneous vertebroplasty: a systematic review and meta-analysis
Background Osteoporotic vertebral compression fractures can substantially affect a patient's life. Percutaneous vertebroplasty is a minimally invasive surgical procedure that can stabilize fractures, reduce pain, and increase the patient's functionality. However, the incidence of secondary fractures post-surgery requires scientific attention. The risk factors that may lead to a new fracture postoperatively must be identified. Purpose To explore the possible risk factors that can predispose to a subsequent fracture after percutaneous vertebroplasty in patients with osteoporotic vertebral compression fractures. Study Design Systematic review and meta-analysis. Methods We systematically searched MEDLINE (PubMed), Embase (ScienceDirect), PEDro, and Cochrane databases from July 2013 through May 2024. The extracted data included patient and clinical characteristics, secondary fractures as the primary outcome, and prognostic factors. Eligible studies for synthesis included one group of patients who had suffered a new fracture after surgery and a group of patients who did not suffer any fracture after vertebroplasty (“non fracture group”). We used the software Medcalc and the web program Meta-Mar for all statistical analyses. SMDs were calculated for continuous data, and ORs were calculated for dichotomous data, both with 95% CI. To quantify statistical heterogeneity across studies, we used chi-squared tests and I2 statistics). The Newcastle–Ottawa Scale was used to assess the quality of studies. Results A total of 3.821 patients from nine studies were included. Median follow-up was 21 months, and overall secondary fracture incidence was 16.6%. The meta-analysis showed that female gender [OR = 1.62, 95% CI 1,26; 2.07, z = 3.79, P = 0.0001], low bone mineral density [SMD = -0,30, 95% CI -0.52; -0.08, z = -2.65, P = 0.008], smoking [OR = 1.62, 95% CI 1.22; 2.15, z = 3.32, P = 0.001] and type 2 diabetes [OR = 1.40, 95% CI 1.11; 1.76, z = 2.83, P = 0.005] were significant risk factors for the secondary fractures after percutaneous vertebroplasty. Conclusion Patients with these identified risk factors should be monitored and treated accordingly to achieve the optimum prognosis after surgery.
- 11 June 2025
- Published by Springer Nature in Osteoporosis International
- Vol. 36 (8) , 1297-1311
Open AccessRisk factors for refracture or new vertebral compression fractures after percutaneous vertebroplasty: a systematic review and meta-analysis
Background Osteoporotic vertebral compression fractures can substantially affect a patient's life. Percutaneous vertebroplasty is a minimally invasive surgical procedure that can stabilize fractures, reduce pain, and increase the patient's functionality. However, the incidence of secondary fractures post-surgery requires scientific attention. The risk factors that may lead to a new fracture postoperatively must be identified. Purpose To explore the possible risk factors that can predispose to a subsequent fracture after percutaneous vertebroplasty in patients with osteoporotic vertebral compression fractures. Study Design Systematic review and meta-analysis. Methods We systematically searched MEDLINE (PubMed), Embase (ScienceDirect), PEDro, and Cochrane databases from July 2013 through May 2024. The extracted data included patient and clinical characteristics, secondary fractures as the primary outcome, and prognostic factors. Eligible studies for synthesis included one group of patients who had suffered a new fracture after surgery and a group of patients who did not suffer any fracture after vertebroplasty (“non fracture group”). We used the software Medcalc and the web program Meta-Mar for all statistical analyses. SMDs were calculated for continuous data, and ORs were calculated for dichotomous data, both with 95% CI. To quantify statistical heterogeneity across studies, we used chi-squared tests and I2 statistics). The Newcastle–Ottawa Scale was used to assess the quality of studies. Results A total of 3.821 patients from nine studies were included. Median follow-up was 21 months, and overall secondary fracture incidence was 16.6%. The meta-analysis showed that female gender [OR = 1.62, 95% CI 1,26; 2.07, z = 3.79, P = 0.0001], low bone mineral density [SMD = -0,30, 95% CI -0.52; -0.08, z = -2.65, P = 0.008], smoking [OR = 1.62, 95% CI 1.22; 2.15, z = 3.32, P = 0.001] and type 2 diabetes [OR = 1.40, 95% CI 1.11; 1.76, z = 2.83, P = 0.005] were significant risk factors for the secondary fractures after percutaneous vertebroplasty. Conclusion Patients with these identified risk factors should be monitored and treated accordingly to achieve the optimum prognosis after surgery.
- 22 June 2024
- Published by Elsevier in Journal of Vascular and Interventional Radiology
- Vol. 35 (9) , 1278-1287.e3
Impact of Percutaneous Cryoablation on Renal Function in Patients with Stage I Renal Cell Carcinoma: A Systematic Review and Meta-Analysis
- 22 June 2024
- Published by Elsevier in Journal of Vascular and Interventional Radiology
- Vol. 35 (9) , 1278-1287.e3
Impact of Percutaneous Cryoablation on Renal Function in Patients with Stage I Renal Cell Carcinoma: A Systematic Review and Meta-Analysis
- Open Access
- 24 October 2023
- Published by Oxford University Press (OUP) in British Journal of Radiology
- Vol. 96 (1152) , 20230383
Percutaneous microwave ablation of hepatic tumors: is there an impact of cirrhotic liver parenchyma upon the volume and short-term assessment of the ablation zone?
Objective: To retrospectively compare and evaluate ablation zone volume and its reduction from baseline to 1 month follow-up post-percutaneous microwave ablation (MWA) between healthy and cirrhotic liver parenchyma. Methods: Institutional database research identified 84 patients (118 hepatic tumors) who underwent percutaneous MWA with the same system. Caudal-right lobe ratio was applied to distinguish cirrhotic (n = 51) and healthy (n = 67) group; ITK-SNAP software was used to quantify ablation zone volume. Long (LAD) and short 1 (SAD-1) and 2 (SAD-2) axis, tumor size diameter (mm) and volume (cm³) of the ablation zones were evaluated for each treated lesion in both groups at baseline (immediately post-ablation) and at 1 month follow-up. Results: There was no significant difference comparing ablation zone volumes at baseline (healthy group: mean ablation volume 14.84 cm³ vs cirrhotic group: mean ablation volume 17.85 cm³, p = 0.31) and 1 month post-ablation (healthy group: mean ablation volume 9.15 cm³ vs cirrhotic group: mean ablation volume 11.58 cm³, p = 0.24). When both “healthy” and “cirrhotic” liver group were evaluated independently, there was a significant difference of ablation volumes reduction (p-value < 0.001) from baseline to 1 month follow-up. When both groups were compared based on reduction (35.12–38.34%) there was no significant difference in ablation zone volumes (p-value = 0.77). Conclusion: Percutaneous MWA results in ablation zones of a comparable volume in both healthy and cirrhotic liver parenchyma. Both cirrhotic and healthy liver parenchyma experience a similar significant reduction of ablation zone volume at 1 month post-therapy. Advances in knowledge statement: This study evaluates and compares the volume of the ablation zone after MWA between healthy and cirrhotic liver parenchyma from baseline to 1 month follow-up and attempts to identify potential differences. It is the first study to demonstrate significant shrinkage of ablation volumes in healthy livers as compared to cirrhotic livers after 4 weeks of follow-up. The results of this study can help us understand the effect of MWA when applied in different backgrounds of liver parenchyma, which could lead to different treatment planning.
- 24 October 2023
- Published by Oxford University Press (OUP) in British Journal of Radiology
- Vol. 96 (1152) , 20230383
Open AccessPercutaneous microwave ablation of hepatic tumors: is there an impact of cirrhotic liver parenchyma upon the volume and short-term assessment of the ablation zone?
Objective: To retrospectively compare and evaluate ablation zone volume and its reduction from baseline to 1 month follow-up post-percutaneous microwave ablation (MWA) between healthy and cirrhotic liver parenchyma. Methods: Institutional database research identified 84 patients (118 hepatic tumors) who underwent percutaneous MWA with the same system. Caudal-right lobe ratio was applied to distinguish cirrhotic (n = 51) and healthy (n = 67) group; ITK-SNAP software was used to quantify ablation zone volume. Long (LAD) and short 1 (SAD-1) and 2 (SAD-2) axis, tumor size diameter (mm) and volume (cm³) of the ablation zones were evaluated for each treated lesion in both groups at baseline (immediately post-ablation) and at 1 month follow-up. Results: There was no significant difference comparing ablation zone volumes at baseline (healthy group: mean ablation volume 14.84 cm³ vs cirrhotic group: mean ablation volume 17.85 cm³, p = 0.31) and 1 month post-ablation (healthy group: mean ablation volume 9.15 cm³ vs cirrhotic group: mean ablation volume 11.58 cm³, p = 0.24). When both “healthy” and “cirrhotic” liver group were evaluated independently, there was a significant difference of ablation volumes reduction (p-value < 0.001) from baseline to 1 month follow-up. When both groups were compared based on reduction (35.12–38.34%) there was no significant difference in ablation zone volumes (p-value = 0.77). Conclusion: Percutaneous MWA results in ablation zones of a comparable volume in both healthy and cirrhotic liver parenchyma. Both cirrhotic and healthy liver parenchyma experience a similar significant reduction of ablation zone volume at 1 month post-therapy. Advances in knowledge statement: This study evaluates and compares the volume of the ablation zone after MWA between healthy and cirrhotic liver parenchyma from baseline to 1 month follow-up and attempts to identify potential differences. It is the first study to demonstrate significant shrinkage of ablation volumes in healthy livers as compared to cirrhotic livers after 4 weeks of follow-up. The results of this study can help us understand the effect of MWA when applied in different backgrounds of liver parenchyma, which could lead to different treatment planning.
- 29 September 2023
- Published by Springer Nature
- p. 217-227
Metastasis
- Open Access
- 25 June 2023
- Published by MDPI AG in Diagnostics
- Vol. 13 (13) , 2164
Intradiscal Gelified Ethanol Nucleolysis versus Endoscopic Surgery for Lumbar Disc Herniation Radiculopathy
The purpose of this study was to retrospectively compare efficacy and safety between intradiscal injection of a gelified ethanol product and tubular discectomy in the treatment of intervertebral disk herniation. A bi-central institutional database research identified forty (40) patients suffering from symptomatic contained disc herniation. Nucleolysis Group included 20 patients [mean 50.05 ± 9.27 years-of-age (male/female 14/6–70/30%)] and Surgery Group included 20 patients [mean 48.45 ± 14.53 years-of-age, (male/female 12/8–60/40%)]. Primary outcome was overall 12-month improvement over baseline in leg pain (NVS units). Procedural technical outcomes were recorded, and adverse events were evaluated at all follow-up intervals. CIRSE classification system was used for complications’ reporting. Mean pre-operative pain score in Nucleolysis Group was 7.95 ± 0.94 reduced to 1.25 ± 1.11 at month 1 and 0.45 ± 0.75 NVS units at year 1. Mean pre-operative pain score in Surgery Group was 7.65 ± 1.13 reduced to 1.55 ± 1.79 at month 1 and 0.70 ± 1.38 NVS units at year 1. Pain decrease was statistically significant after both procedures (p < 0.001). There was no statistically significant difference between pain reduction in both groups (p = 0.347). The decrease differences of the pain effect upon general activities, sleeping, socializing, walking, and enjoying life in the follow-up period between the two groups were not statistically significant. No complications were noted in both groups. Results from the current study report that intradiscal injection of a gelified ethanol and tubular discectomy were equally effective on terms of efficacy and safety for the treatment of symptomatic lumbar intervertebral disc herniation regarding the 12-month mean leg pain improvement. Both achieved similar rapid significant clinical improvement persisting throughout follow-up period.
- 25 June 2023
- Published by MDPI AG in Diagnostics
- Vol. 13 (13) , 2164
Open AccessIntradiscal Gelified Ethanol Nucleolysis versus Endoscopic Surgery for Lumbar Disc Herniation Radiculopathy
The purpose of this study was to retrospectively compare efficacy and safety between intradiscal injection of a gelified ethanol product and tubular discectomy in the treatment of intervertebral disk herniation. A bi-central institutional database research identified forty (40) patients suffering from symptomatic contained disc herniation. Nucleolysis Group included 20 patients [mean 50.05 ± 9.27 years-of-age (male/female 14/6–70/30%)] and Surgery Group included 20 patients [mean 48.45 ± 14.53 years-of-age, (male/female 12/8–60/40%)]. Primary outcome was overall 12-month improvement over baseline in leg pain (NVS units). Procedural technical outcomes were recorded, and adverse events were evaluated at all follow-up intervals. CIRSE classification system was used for complications’ reporting. Mean pre-operative pain score in Nucleolysis Group was 7.95 ± 0.94 reduced to 1.25 ± 1.11 at month 1 and 0.45 ± 0.75 NVS units at year 1. Mean pre-operative pain score in Surgery Group was 7.65 ± 1.13 reduced to 1.55 ± 1.79 at month 1 and 0.70 ± 1.38 NVS units at year 1. Pain decrease was statistically significant after both procedures (p < 0.001). There was no statistically significant difference between pain reduction in both groups (p = 0.347). The decrease differences of the pain effect upon general activities, sleeping, socializing, walking, and enjoying life in the follow-up period between the two groups were not statistically significant. No complications were noted in both groups. Results from the current study report that intradiscal injection of a gelified ethanol and tubular discectomy were equally effective on terms of efficacy and safety for the treatment of symptomatic lumbar intervertebral disc herniation regarding the 12-month mean leg pain improvement. Both achieved similar rapid significant clinical improvement persisting throughout follow-up period.
- Open Access
Role of Percutaneous Ablation in the Management of Intrahepatic Cholangiocarcinoma
Cholangiocarcinoma (CCA) is an invasive cancer accounting for <1% of all cancers and 10–15% of primary liver cancers. Intrahepatic CCA (iCCA) is associated with poor survival rates and high post-surgical recurrence rates whilst most diagnosed patients are not surgical candidates. There is a growing literature suggesting percutaneous ablative techniques for the management of patients with iCCA measuring ≤3 cm with contraindications to surgery as well as for recurrent or residual tumors aiming to provide local cancer treatment and control. Most used ablative therapies for iCCA include radiofrequency and microwave ablation with irreversible electroporation, cryoablation and reversible electroporation (electrochemotherapy) being less commonly encountered techniques. Due to the infiltrative margins of the lesion, there is a need for larger safety margins and ablation zone; multi-apparatus ablation or other variations of the technique such as balloon-assisted approaches can be utilized aiming to increase size of the zone of necrosis. The present review paper focuses upon the current role of percutaneous ablative techniques for the therapeutic management of iCCA. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of iCCA, including local control and survival rates.
Open AccessRole of Percutaneous Ablation in the Management of Intrahepatic Cholangiocarcinoma
Cholangiocarcinoma (CCA) is an invasive cancer accounting for <1% of all cancers and 10–15% of primary liver cancers. Intrahepatic CCA (iCCA) is associated with poor survival rates and high post-surgical recurrence rates whilst most diagnosed patients are not surgical candidates. There is a growing literature suggesting percutaneous ablative techniques for the management of patients with iCCA measuring ≤3 cm with contraindications to surgery as well as for recurrent or residual tumors aiming to provide local cancer treatment and control. Most used ablative therapies for iCCA include radiofrequency and microwave ablation with irreversible electroporation, cryoablation and reversible electroporation (electrochemotherapy) being less commonly encountered techniques. Due to the infiltrative margins of the lesion, there is a need for larger safety margins and ablation zone; multi-apparatus ablation or other variations of the technique such as balloon-assisted approaches can be utilized aiming to increase size of the zone of necrosis. The present review paper focuses upon the current role of percutaneous ablative techniques for the therapeutic management of iCCA. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of iCCA, including local control and survival rates.
- 1 April 2023
- Published by Radiological Society of North America (RSNA) in Radiology
- Vol. 307 (2) , e222944
Radiation Therapy Castle Under Siege: Will It Hold or Fold?
- 1 April 2023
- Published by Radiological Society of North America (RSNA) in Radiology
- Vol. 307 (2) , e222944
Radiation Therapy Castle Under Siege: Will It Hold or Fold?
- Open Access
Ablative Techniques for Sarcoma Metastatic Disease: Current Role and Clinical Applications
Sarcomas are heterogenous mesenchymal neoplasms with more than 80 different histologic subtypes. Lung followed by liver and bone are the most common sites of sarcoma metastatic disease. Ablative techniques have been recently added as an additional alternative curative or palliative therapeutic tool in sarcoma metastatic disease. When compared to surgery, ablative techniques are less invasive therapies which can be performed even in non-surgical candidates and are related to decreased recovery time as well as preservation of the treated organ’s long-term function. Literature data upon ablative techniques for sarcoma metastatic disease are quite heterogeneous and variable regarding the size and the number of the treated lesions and the different histologic subtypes of the original soft tissue or bone sarcoma. The present study focuses upon the current role of minimal invasive thermal ablative techniques for the management of metastatic sarcoma disease. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of metastatic soft tissue and bone sarcoma, including local control and survival rates.
Open AccessAblative Techniques for Sarcoma Metastatic Disease: Current Role and Clinical Applications
Sarcomas are heterogenous mesenchymal neoplasms with more than 80 different histologic subtypes. Lung followed by liver and bone are the most common sites of sarcoma metastatic disease. Ablative techniques have been recently added as an additional alternative curative or palliative therapeutic tool in sarcoma metastatic disease. When compared to surgery, ablative techniques are less invasive therapies which can be performed even in non-surgical candidates and are related to decreased recovery time as well as preservation of the treated organ’s long-term function. Literature data upon ablative techniques for sarcoma metastatic disease are quite heterogeneous and variable regarding the size and the number of the treated lesions and the different histologic subtypes of the original soft tissue or bone sarcoma. The present study focuses upon the current role of minimal invasive thermal ablative techniques for the management of metastatic sarcoma disease. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of metastatic soft tissue and bone sarcoma, including local control and survival rates.
- Open Access
Emerging Indications for Interventional Oncology: Expert Discussion on New Locoregional Treatments
Interventional oncology (IO) employs image-guided techniques to perform minimally invasive procedures, providing lower-risk alternatives to many traditional medical and surgical therapies for cancer patients. Since its advent, due to rapidly evolving research development, its role has expanded to encompass the diagnosis and treatment of diseases across multiple body systems. In detail, interventional oncology is expanding its role across a wide spectrum of disease sites, offering a potential cure, control, or palliative care for many types of cancer patients. Due to its widespread use, a comprehensive review of the new indications for locoregional procedures is mandatory. This article summarizes the expert discussion and report from the “MIOLive Meet SIO” (Society of Interventional Oncology) session during the last MIOLive 2022 (Mediterranean Interventional Oncology Live) congress held in Rome, Italy, integrating evidence-reported literature and experience-based perceptions. The aim of this paper is to provide an updated review of the new techniques and devices available for innovative indications not only to residents and fellows but also to colleagues approaching locoregional treatments.
Open AccessEmerging Indications for Interventional Oncology: Expert Discussion on New Locoregional Treatments
Interventional oncology (IO) employs image-guided techniques to perform minimally invasive procedures, providing lower-risk alternatives to many traditional medical and surgical therapies for cancer patients. Since its advent, due to rapidly evolving research development, its role has expanded to encompass the diagnosis and treatment of diseases across multiple body systems. In detail, interventional oncology is expanding its role across a wide spectrum of disease sites, offering a potential cure, control, or palliative care for many types of cancer patients. Due to its widespread use, a comprehensive review of the new indications for locoregional procedures is mandatory. This article summarizes the expert discussion and report from the “MIOLive Meet SIO” (Society of Interventional Oncology) session during the last MIOLive 2022 (Mediterranean Interventional Oncology Live) congress held in Rome, Italy, integrating evidence-reported literature and experience-based perceptions. The aim of this paper is to provide an updated review of the new techniques and devices available for innovative indications not only to residents and fellows but also to colleagues approaching locoregional treatments.
- Open Access
Vertebral Augmentation: Is It Time to Get Past the Pain? A Consensus Statement from the Sardinia Spine and Stroke Congress
Vertebral augmentation has been used to treat painful vertebral compression fractures and metastatic lesions in millions of patients around the world. An international group of subject matter experts have considered the evidence, including but not limited to mortality. These considerations led them to ask whether it is appropriate to allow the subjective measure of pain to so dominate the clinical decision of whether to proceed with augmentation. The discussions that ensued are related below.
Open AccessVertebral Augmentation: Is It Time to Get Past the Pain? A Consensus Statement from the Sardinia Spine and Stroke Congress
Vertebral augmentation has been used to treat painful vertebral compression fractures and metastatic lesions in millions of patients around the world. An international group of subject matter experts have considered the evidence, including but not limited to mortality. These considerations led them to ask whether it is appropriate to allow the subjective measure of pain to so dominate the clinical decision of whether to proceed with augmentation. The discussions that ensued are related below.