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Dive into the research topics where Ioannis Varkarakis is active.

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Featured researches published by Ioannis Varkarakis.


Urological Research | 2006

Bladder lithiasis: from open surgery to lithotripsy

Athanasios Papatsoris; Ioannis Varkarakis; Athanasios Dellis; Charalambos Deliveliotis

Bladder calculi account for 5% of urinary calculi and usually occur because of bladder outlet obstruction, neurogenic voiding dysfunction, infection, or foreign bodies. Children remain at high risk for developing bladder lithiasis in endemic areas. Males with prostate disease or relevant surgery and women who undergo anti-incontinence surgery are at a higher risk for developing vesical lithiasis. Open surgery remains the main treatment of bladder calculus in children. In adults, the classical treatment for bladder calculi is endoscopic transurethral disintegration with mechanical cystolithotripsy, ultrasound, electrohydraulic lithotripsy, Swiss Lithoclast, and holmium:YAG laser. Novel modifications of these treatment modalities have been used for large calculi. Open and endoscopic surgery requires anesthesia and hospitalization. Alternatively, extracorporeal shock wave lithotripsy has been demonstrated to be simple, effective, and well tolerated in high-risk patients. Recently, simultaneous percutaeous suprapubic and transurethral cystolithotripsy has been tested as well as percutaneous cystolithotomy by using a laparoscopic entrapment sac.


BMJ Open | 2014

The safety and efficacy of irreversible electroporation for the ablation of prostate cancer: a multicentre prospective human in vivo pilot study protocol

W. van den Bos; D. M. de Bruin; B.G. Muller; Ioannis Varkarakis; A.A. Karagiannis; Patricia J. Zondervan; M.P. Laguna Pes; Denise P. Veelo; C D Savci Heijink; Marc R. Engelbrecht; Hessel Wijkstra; T.M. De Reijke; J.J.M.C.H. de la Rosette

Introduction Current surgical and ablative treatment options for prostate cancer have a relatively high incidence of side effects, which may diminish the quality of life. The side effects are a consequence of procedure-related damage of the blood vessels, bowel, urethra or neurovascular bundle. Ablation with irreversible electroporation (IRE) has shown to be effective in destroying tumour cells and harbours the advantage of sparing surrounding tissue and vital structures. The aim of the study is to evaluate the safety and efficacy and to acquire data on patient experience of minimally invasive, transperineally image-guided IRE for the focal ablation of prostate cancer. Methods and analysis In this multicentre pilot study, 16 patients with prostate cancer who are scheduled for a radical prostatectomy will undergo an IRE procedure, approximately 30 days prior to the radical prostatectomy. Data as adverse events, side effects, functional outcomes, pain and quality of life will be collected and patients will be controlled at 1 and 2 weeks post-IRE, 1 day preprostatectomy and postprostatectomy. Prior to the IRE procedure and the radical prostatectomy, all patients will undergo a multiparametric MRI and contrast-enhanced ultrasound of the prostate. The efficacy of ablation will be determined by whole mount histopathological examination, which will be correlated with the imaging of the ablation zone. Ethics and dissemination The protocol is approved by the ethics committee at the coordinating centre (Academic Medical Center (AMC) Amsterdam) and by the local Institutional Review Board at the participating centres. Data will be presented at international conferences and published in peer-reviewed journals. Conclusions This pilot study will determine the safety and efficacy of IRE in the prostate. It will show the radiological and histopathological effects of IRE ablations and it will provide data to construct an accurate treatment planning tool for IRE in prostate tissue. Trial registration number Clinicaltrials.gov database: NCT01790451.


International Journal of Nursing Practice | 2009

Problems faced by relatives caring for cancer patients at home.

Thomas Tsigaroppoulos; Evangelos Mazaris; Eleftherios Chatzidarellis; Andreas Skolarikos; Ioannis Varkarakis; Charalambos Deliveliotis

The care of patients suffering from advanced cancer is not limited in the hospital setting. It continues at home where the burden of care is borne by specific individuals. The aim of the present study was to survey and record the various problems faced by those who care for cancer patients at home. The study was conducted in our hospital during the summer of 2007. All participants completed, during a personal interview, a questionnaire which covered pathologic, social, psychological, spiritual/religious and financial problems. Seventy-six carers returned fully completed questionnaires. The most frequent problems reported were: anxiety regarding the patients future (61.8%), troublesome symptoms such as pain (54%), increased economic burden-financial difficulty (51.3%), problems with patients feeding (50%), unhappiness or depression (48,7%), emotional upset (47.4%), worsening of the patients behaviour and personality (38.2%), difficulty of establishing a positive attitude regarding their current status (34.2%), transport to hospital (32.9%), assistance from the wider family circle (25%). Taking care of cancer patients at home creates several problems among carers. Many of them remain undetected. The acknowledgement and recognition of these problems by health-care professionals might contribute to finding solutions in order to assist the difficult task of these individuals.


World Journal of Urology | 2016

Standardization of definitions in focal therapy of prostate cancer: report from a Delphi consensus project

A. W. Postema; T.M. De Reijke; Osamu Ukimura; W. van den Bos; A. R. Azzouzi; Eric Barret; D. Baumunk; Andreas Blana; Alberto Bossi; Maurizio Brausi; Jonathan A. Coleman; Sebastien Crouzet; Jose Luis Dominguez-Escrig; Roman Ganzer; Sandeep Ghai; Inderbir S. Gill; Rajan T. Gupta; T. Henkel; Markus Hohenfellner; J. S. Jones; Frank Kahmann; Christof Kastner; K. U. Köhrmann; G. Kovacs; R. Miano; R. J. A. van Moorselaar; N. Mottet; L. Osorio; Bradley R. Pieters; Thomas J. Polascik

PurposeTo reach standardized terminology in focal therapy (FT) for prostate cancer (PCa).MethodsA four-stage modified Delphi consensus project was undertaken among a panel of international experts in the field of FT for PCa. Data on terminology in FT was collected from the panel by three rounds of online questionnaires. During a face-to-face meeting on June 21, 2015, attended by 38 experts, all data from the online rounds were reviewed and recommendations for definitions were formulated.ResultsConsensus was attained on 23 of 27 topics; TargetedFT was defined as a lesion-based treatment strategy, treating all identified significant cancer foci; FT was generically defined as an anatomy-based (zonal) treatment strategy. Treatment failure due to the ablative energy inadequately destroying treated tissue is defined as ablation failure. In targeting failure the energy is not adequately applied to the tumor spatially and selection failure occurs when a patient was wrongfully selected for FT. No definition of biochemical recurrence can be recommended based on the current data. Important definitions for outcome measures are potency (minimum IIEF-5 score of 21), incontinence (new need for pads or leakage) and deterioration in urinary function (increase in IPSS >5 points). No agreement on the best quality of life tool was established, but UCLA-EPIC and EORTC-QLQ-30 were most commonly supported by the experts. A complete overview of statements is presented in the text.ConclusionFocal therapy is an emerging field of PCa therapeutics. Standardization of definitions helps to create comparable research results and facilitate clear communication in clinical practice.


The Journal of Urology | 2016

Histopathological Outcomes after Irreversible Electroporation for Prostate Cancer: Results of an Ablate and Resect Study

W. van den Bos; R. R. Jurhill; D. M. de Bruin; C.D. Savci-Heijink; Arnoud W. Postema; Peter G. K. Wagstaff; B.G. Muller; Ioannis Varkarakis; Andreas Skolarikos; Patricia J. Zondervan; M.P. Laguna Pes; T.M. De Reijke; J.J.M.C.H. de la Rosette

PURPOSE Irreversible electroporation is a tissue ablation modality that uses high voltage electric energy to induce an increase in cell membrane permeability. This causes destabilization of the existing cellular transmembrane potential leading to cell death, due to the inability to maintain cellular homeostasis. This phase I-II study was designed to evaluate the histopathological outcomes of irreversible electroporation to prostate and surrounding tissue in radical prostatectomy specimens. MATERIALS AND METHODS Sixteen patients with prostate cancer underwent an irreversible electroporation ablation without curative intent, followed by radical prostatectomy scheduled 4 weeks later. For histopathological examination of the prostate, whole mounted tissue slices were examined by dedicated genitourinary pathologists. The borders of the ablation zone and residual tumor were outlined on the slides. RESULTS The irreversible electroporation ablation zones were characterized as areas of fibrosis, necrosis and loss of epithelial tissue in terms of denudation in the glandular structures. The ablation zone was well demarcated, showing trenchant delineations between viable and nonviable tissue. The ablated tissue showed mild to moderate inflammation, with atrophic cells in 1 case. The area was surrounded by hemorrhage at the location of the electrodes. No skip lesions or viable tissue was seen in the ablation zone. Fibrinoid necrosis of the neurovascular bundle was observed in 13 patients and denudation of the urothelium of the prostatic urethra was seen in 9. CONCLUSIONS Histopathological assessment of the prostate 4 weeks after irreversible electroporation ablation showed sharply demarcated fibrotic and necrotic tissue in the ablation zone. No viable tissue was observed in the irreversible electroporation ablation zone.


Urologia Internationalis | 2005

Use of external ureteral catheters and internal double J stents in a modified ileal neobladder for continent diversion: a comparative analysis.

Ioannis Varkarakis; Athanasios Delis; Athanasios Papatsoris; Charalambos Deliveliotis

Introduction: Open-ended straight ureteral stents are typically used for the support of the ureteroileal anastomosis during the creation of an orthotopic ‘S-pouch’ ileal neobladder. The use of double J stents as an alternative in this setting is evaluated. Materials and Methods: Medical charts from 43 patients undergoing radical cystectomy with formation of an ileal ‘S-pouch’ neobladder were retrospectively evaluated. In 30 patients (group A), a 6-Fr open-ended straight ureteral catheter was used to stent the ureteroileal anastomosis, while a double J stent was used for the same reason in 13 patients (group B). The ureteral catheter was removed 15 days after the procedure while the double J stent 3 weeks postoperatively. Hospital stay, early and late complications were evaluated for both groups during a mean follow-up period of 22.5 and 19.6 months respectively. Results: Stricture of the ureteroileal anastomosis was observed in 2 (6.6%) and 1 (7.6%) patient of groups A and B respectively. All complications presented with similar rates, except for an increased but not statistically significant incidence of urethrovesical anastomotic leakage and early urinary tract infections in group B. Hospital stay was significantly (p < 0.005) shorter for patients of group B (9.9 vs. 15.2 days). Conclusions: The use of double J stents to support the ureteroileal anastomosis can be used as an alternative to open-ended ureteral stents. With double J stents a shorter hospital stay was achieved with similar complication rates but a higher incidence of upper urinary tract infections.


BJUI | 2005

Local steroid application during nerve‐sparing radical retropubic prostatectomy

Charalambos Deliveliotis; Athanasios Delis; Athanasios Papatsoris; N. Antoniou; Ioannis Varkarakis

To evaluate the effect on potency rates after surgery of applying local steroids to the neurovascular bundles (NVBs) of the prostate after bilateral nerve‐sparing radical retropubic prostatectomy (BNS‐RRP).


Urology | 2008

Use of nonsteroidal anti-inflammatory drugs after radical retropubic prostatectomy: a prospective, randomized trial.

Evangelos Mazaris; Ioannis Varkarakis; Michael Chrisofos; Andreas Skolarikos; Konstantinos Ioannidis; Athanasios Dellis; Athanasios Papatsoris; Charalambos Deliveliotis

OBJECTIVES To assess the efficacy and safety of nonsteroidal anti-inflammatory drugs (NSAIDs) administered after radical retropubic prostatectomy (RRP). METHODS One hundred patients undergoing open RRP by one surgeon were divided randomly and prospectively into two groups of 50 patients, each receiving systematically either an NSAID (lornoxicam) or paracetamol for postoperative analgesia. Opiates were administered if needed for breakthrough pain. Parameters potentially correlated with postoperative bleeding, such as preoperative and postoperative hemoglobin (Hb) differences, estimated blood loss, number of transfusions, and drain output were recorded. Furthermore, the degree of pain was assessed daily with a visual analogue scale score until discharge from hospital. RESULTS After procedures with similar estimated blood loss, postoperative bleeding was not more in the NSAIDs group, as evidenced by similar transfusion rates (P <or=1), similar postoperative Hb values (P >0.05), and Hb drop after the procedure. No patient required re-exploration for bleeding; drain output when elevated was never attributed to postoperative bleeding. Pain control as evaluated by the visual analogue scale pain score was adequate with the use of NSAIDs and not statistically different from the non-NSAIDs group during postoperative days 1 and 4 and onward. Pain control with lornoxicam was even better on postoperative days 2 and 3 (P <or=0.05). CONCLUSIONS Nonsteroidal anti-inflammatory drugs administered after open RRP are safe and effective. They do not increase the risk of bleeding and offer improved analgesia.


Tumori | 2008

Upper urinary tract transitional cell carcinoma. A 10-year experience

Athanasios Papatsoris; Michael Chrisofos; Andreas Skolarikos; Ioannis Varkarakis; A. Lekas; Athanasios Dellis; Sotirios Koritsiadis; Charalambos Deliveliotis

Objective To present our 10-year experience with patients surgically treated for upper urinary tract transitional cell carcinoma. Patients and methods We reviewed the medical records of 264 patients (218 males and 46 females), aged 37–93 years (mean, 69.5), treated surgically for upper tract transitional cell carcinoma during the period January 1996 to December 2005. Results During the mean follow-up of 58 months (range, 12–120), local relapse was diagnosed in 14% of the patients. The mean time to recurrence was 13 months (range, 1–102). The overall mortality was 14%, and the mean survival was 109 months. Survival was significantly influenced by the following parameters: male gender (P = 0.0151), age over 80 years (P = 0.0012), location in both the pelviocaliceal system and the ureter (P = 0.051), a two incision operation (P = 0.0075), grade III (P = 0.0314), stage T3 and T4 (P <0.0001). Conclusions Tumor stage was identified as the most important determinant in predicting recurrence and survival. Other predictors of survival included male gender, age over 80 years, location in the pelviocaliceal system and the ureter, a two incision operation, and high grade.


Nature Clinical Practice Urology | 2007

The importance of crossing vessels in ureteropelvic junction obstruction

Ioannis Varkarakis; Charalambos Deliveliotis

With the popularization of laparoscopic and robotic pyeloplasty has come a resurgence in the debate over the role of crossing vessels in the pathogenesis of UPJ obstruction. In this Viewpoint, the authors examine the evidence and argue that crossing vessels are implicated in the etiology of UPJ obstruction and are important because of their potential to lead to cause surgical complications if they are not recognized.

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Charalambos Deliveliotis

National and Kapodistrian University of Athens

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Andreas Skolarikos

National and Kapodistrian University of Athens

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Athanasios Papatsoris

National and Kapodistrian University of Athens

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Athanasios Dellis

National and Kapodistrian University of Athens

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B.G. Muller

University of Amsterdam

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Athanasios Delis

National and Kapodistrian University of Athens

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