Berkan Resorlu

Bezmiâlem Vakif Üniversitesi, İstanbul, Istanbul, Turkey

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Publications (74)127.25 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: Purpose: To review our intraoperative complications of retrograde intrarenal surgery (RIRS) for kidney calculi and stratify these complications according to the modified Satava classification system (SCS). Patients and Methods: 230 patients (119 males, 111 females) who underwent RIRS because of kidney calculi were analyzed. We documented and stratified the intraoperative complications according to the modified SCS. There are four grades for this classification: grade 1 complications include events without consequences for patients; grade 2a complications include events that could be treated with endoscopic surgery intraoperatively; grade 2b complications include events which were treated with endoscopic treatment in another session, and grade 3 describes the events requiring laparoscopic or open surgery. Results: Mean age was 39.1 years (range 1-78). The stone-free rate after one session was 81%. Intraoperative complications were recorded in 30.4% of the patients. According to the modified SCS, grade 1 complications were documented in 15.9%, grade 2a complications were documented in 5.6%, and grade 2b complications were documented in 8.9% of the patients. Grade 3 complications were not detected in any of the patients. Conclusion: In our opinion, the modified SCS can facilitate patients to understand the safety of this surgery and can make it easier to compare the results of different institutes and surgeons. © 2014 S. Karger AG, Basel.
    Urologia Internationalis 02/2014; · 1.07 Impact Factor
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    ABSTRACT: We aimed to evaluate the effectiveness of percutaneous nephrolithotomy (PNL), stone-free rates, and related complications in children with radiolucent renal stones. A total of 56 patients aged <16 years from four institutions were enrolled in our study. Asymptomatic, clinically insignificant residual fragments measuring <4 mm or a complete stone-free status was accepted as the criterion for clinical success. Complications were evaluated according to the modified Clavien classification. The mean age of the patients was 7.8 ± 4.5 years. The mean stone size was calculated as 24.07 ± 10.4 mm. The median operative and fluoroscopy times were 53.2 min (15-170 min) and 172.4 s (5-520 s), respectively. The success rate after PNL monotherapy was 87.4 %; the total success rate with shock wave lithotripsy used as an auxillary treatment method was detected as 94.6 %. The total complication rate was 19.6 % (11 patients). No adjacent organ injury was observed. All of the complications that occurred were minor according to the Clavien classification (Clavien Grades I-II). PNL can be applied to radiolucent pediatric renal stones in children with similar success, and complication rates as noted for radiopaque stones.
    Urolithiasis. 10/2013;
  • Ural Oğuz, Berkan Resorlu, Ali Unsal
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    ABSTRACT: To determine the metabolic risk factors in children and adults with urinary system stone disease. Between September 2008 and February 2011, 257 patients who underwent 24-h urine analysis because of urinary system stone disease were included in the present study. Group I and II include only adult patients. The first-time stone formers were named as Group I (n = 106), and recurrent stone formers were named as Group II (n = 107). Group III was occurred by pediatric patients (n = 44). Control group includes 105 people was called as Group IV. This group was divided into two subgroups. Group IVa includes 70 adult people, and Group IVb includes 35 children. The metabolic evaluation results of patients and control groups were compared. Hypercalciuria (35.8, 44.9, and 47.7 % for Group I, II, and III, respectively) and hypocitraturia (42.5, 40.2, and 50 % for Group I, II, and III, respectively) were most common risk factors for stone formation. However, unlike the literature, we have seen that hypomagnesiuria is also an important risk factor in adults and children. Hypomagnesiuria was defined at 36.4 % in Group I, 29 % in Group II, and 56.8 % in Group III (p < 0.05 for each group). These three parameters were significantly different between patient and control groups. Hypomagnesiuria, hypocitraturia, and hypercalciuria are the most important risk factors for stone formation in adults and pediatric patients.
    International Urology and Nephrology 08/2013; · 1.33 Impact Factor
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    ABSTRACT: Objectives: To examine the feasibility of retrograde intrarenal surgery (RIRS) in a porcine model. Materials and Methods: Female pigs (n = 3) were placed in a dorsal lithotomy position under general anesthesia, and stone material was inserted into the renal pelvis of the pigs. The bladder was entered with a cystoscope, and a 0.038-inch hydrophilic guidewire was passed into the renal pelvis. Following successful placement of the guidewire, a ureteral access sheath (9.5/11.5 Fr) was placed to allow for optimal visualization. A 7.5-Fr flexible ureteroscope (Karl Storz Flex-X2) and a 200-μm laser fiber were used for lithotripsy. When basketing was deemed necessary, zero-tipped nitinol stone baskets were used. Trainees then practiced all these manipulations on the model. Results: Urologists with moderate experience in advanced endourologic surgery were trained using this model. However, there were some surgical difficulties due to the urinary system anatomy of the pig. Intravaginal location of the urethra, bladder neck location of the ureters, tight ureteric orifices, tortuous ureters, longitudinally elongated renal pelvis, narrow infundibulopelvic angle and shallow calices made the passage of the instruments and maneuverability of the flexible ureteroscope more difficult than in a human model. Conclusions: Despite some difficulties, our porcine model was very effective, because all the trainees successfully practiced the RIRS manipulations on this model.
    Urologia Internationalis 08/2013; · 1.07 Impact Factor
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    ABSTRACT: The objective of the study was to investigate the precise role of computed tomography (CT) in preoperative radiologic evaluation and surgical planning of kidney stone in children prior to percutaneous nephrolithotomy (PNL). A total of 113 pediatric patients (aged ≤18 years) undergoing PNL for renal stone(s) in three referral hospitals between March 2010 and August 2012 were retrospectively evaluated. Depending on the preoperative radiologic evaluation, patients were divided into two groups. Those evaluated with CT were classified as group-1 (n = 50) and the remaining cases undergoing intravenous urography (IVU) examination were classified as group-2 (n = 63). Patient- and procedure-related variables and perioperative measures were compared between the groups. The mean age, stone size and localization were similar in both groups (p = 0.07, p = 0.57, p = 0.6, respectively). Although the postoperative hemoglobin drop was found to be significantly higher in group-2 (1.5 ± 1.3 vs. 0.9 ± 0.6 g/dL, p = 0.005), the mean operation time, fluoroscopic screening time, access number, overall success and complication rates were comparable (p = 0.06, p = 0.94, p = 0.75, p = 041, and p = 0.41, respectively). However, the mean hospitalization time was significantly prolonged in group-2 than in group-1 (p = 0.03). Our findings clearly demonstrate that, despite the key role of preoperative CT in particular patients with anatomically abnormal kidneys, IVU is a valuable alternative imaging modality with comparable radiation doses in children.
    Urolithiasis. 08/2013;
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    ABSTRACT: The aim of the study to compare outcomes of flexible ureterorenoscopy in patients with different body mass index (BMI) scores and to explore whether the BMI has an effect on outcomes of RIRS. Five hundred and two patients who underwent flexible URS in 3 centers between 2008 and 2012 for the management of single upper urinary tract calculi were retrospectively reviewed. Patients were categorized as normal weight BMI 18.5 to 24.99 kg/m(2), overweight 25 to 29.99 kg/m(2), obese 30 to 39.99 kg/m(2) and morbid obese >40 kg/m(2).The groups were assessed in terms of demographic parameters including age, gender, stone size, intraoperative and postoperative variables. The mean patient age was 41.3 ± 15.51 (18-81) years and with an average BMI 26.68 ± 5.2 kg/m(2) (16.64-55.15 kg/m²). Of the patients, 43.2 % had normal weight (NW), 32.2 % were overweight (OW), 21.9 % were obese (O) and 2.5 % were morbidly obese (MO). Stone-free rates after single procedure in NW, OW, O, MO groups were 60.8, 61.7, 73.6, 61.5 %, respectively (p = 0.079). Overall targeted stone-free rates were also similar in four groups (88.9, 90.1, 93.6, 90.4 %, p = 0.586). There were no statistically significant differences in the frequency of complications and mean hospitalization time among the groups (p > 0.05). In conclusion, this study demonstrated that flexible URS is a valuable option for the treatment of kidney stone in both obese and non-obese patients. BMI did not influence the postoperative outcomes.
    Urolithiasis. 07/2013;
  • World Journal of Urology 06/2013; · 2.89 Impact Factor
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    ABSTRACT: To assess the significance of asymptomatic residual stone fragments of less than 4mm (clinically insignificant residual fragments [CIRFs]) after shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PNL), and retrograde intrarenal surgery (RIRS) in children. Eighty-five children were followed up for 6 to 50months (median 22). Outcomes measured were fragment re-growth, stone events (emergency department visits, hospitalization, or additional interventions) and spontaneous fragment passage. During follow-up, 22 children (25.8%) passed residual fragments spontaneously. Highest spontaneous passage rate was found for renal pelvis stones and the lowest for the lower pole stones (57.1% vs. 16.1%; p<0.001). When the number of the fragments increased, the chance of the spontaneous passage decreased (30% vs 20%; p<0.05). Symptomatic episodes including renal colic, hematuria, or urinary tract infection were documented in 34 (40%) patients, and re-growth of fragments was observed in 18 (21.2%). Stone size had no significant effect on spontaneous passage (p=0.079), stone growth (p=0.528), and symptomatic episodes (p=0.402). Twenty-five patients (29.4%) required secondary intervention for stone re-growth or stone related events and the remaining 20 patients (23.5%) needed medical treatment for bothersome symptoms or complications. Our results suggest that 40% of children with CIRFs will become symptomatic and 20% will develop stone re-growth over the following 6months. Only one fifth of the fragments will pass spontaneously without any complications. Therefore, the use of the term "CIRF" is not appropriate for postoperative residual fragments in children.
    Journal of Pediatric Surgery 04/2013; 48(4):840-4. · 1.38 Impact Factor
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    ABSTRACT: OBJECTIVES: To review our experience with ureteroscopy (URS) in the treatment of ureteral calculi and stratify intraoperative complications of URS according to the modified Satava classification system. PATIENTS AND METHODS: We performed a retrospective analysis of 1,208 patients (672 males and 536 females), with a mean age of 43.1 years (range 1-78), who underwent ureteroscopic procedures for removal of ureteral stones. Intraoperative complications were recorded according to modified Satava classification system. Grade 1 complications included incidents without consequences for the patient; grade 2 complications, which are treated intraoperatively with endoscopic surgery (grade 2a) or required endoscopic re-treatment (grade 2b); and grade 3 complications included incidents requiring open or laparoscopic surgery. RESULTS: The stones were completely removed in 1,067 (88.3 %) patients after primary procedure by either simple extraction or after fragmentation. The overall incidence of intraoperative complications was 12.6 %. The most common complications were proximal stone migration (3.9 %), mucosal injury (2.8 %), bleeding (1.9 %), inability to reach stone (1.8 %), malfunctioning or breakage of instruments (0.8 %), ureteral perforation (0.8 %) and ureteral avulsion (0.16 %). According to modified Satava classification system, there were 4.5 % grade 1; 4.4 % grade 2a; 3.2 % grade 2b; and 0.57 % grade 3 complications. CONCLUSION: We think that modified Satava classification is a quick and simple system for describing the severity of intraoperative URS complications and this grading system will facilitate a better comparison for the surgical outcomes obtained from different centers.
    World Journal of Urology 03/2013; · 2.89 Impact Factor
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    ABSTRACT: Retrograde intrarenal surgery (RIRS) in patients with horseshoe kidneys (HSKs) remains poorly studied. The present study aimed to assess clinical success and stone-free rates in HSK patients with renal stones treated with flexible ureteroscopy. RIRS was attempted in 20 patients with 25 renal stones in HSK from December 2008 to January 2012. The patients were evaluated with imaging studies including plain abdominal radiography, intravenous urogram, abdominal ultrasonography or non-contrast tomography scan. Success rate was defined as stone-free or residual fragment less than 4 mm. Pre-operative, operative and postoperative data were retrospectively analyzed. A total of 20 patients were included in the present study (12 males, 8 females). 9 of 25 renal stones (36 %) were located in the lower calyx of the kidney, whereas 7 (28 %) in the middle calyx, 5 (20 %) in the renal pelvis and 4 (16 %) in the upper calyx. The mean stone size was 17.8 ± 4.5 mm. The stone-free rate was 70 % after a single procedure. 6 patients required shock wave lithotripsy and two of these were completely stone-free. Average hospital stay was 1.4 ± 0.7 days. Minor complications as classified by Clavien I or II occurred in 25 %. No major complications (Clavien III-V) occurred in the study group. RIRS is an effective and safe treatment modality for renal stones in patients with HSK. The procedure has minimal morbidity and high success rate.
    Urolithiasis. 02/2013; 41(1):79-83.
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    ABSTRACT: Objectives: It was the aim of this study to evaluate and compare the outcomes of percutaneous nephrolithotomy (PNL) for the treatment of posterior and anterior caliceal stones. Patients and Methods: We performed a retrospective analysis of 86 patients with isolated caliceal stones who underwent PNL between 2011 and 2012. The patients were classified into two groups according to the localization of the stone, either in the anterior (group 1, n = 41) or posterior (group 2, n = 45) calyx, on axial plane computed tomography. Results: The mean age, male/female ratio and stone size and location were similar in both groups. Fluoroscopy, operation time and duration of hospitalization were also similar between groups. Patients in group 1 had a greater postoperative hemoglobin drop than patients in group 2. Blood transfusion was required for 5 patients in group 1 and for 4 patients in group 2. In addition, open conversion was required for 2 patients in group 1 during the early postoperative period because of extensive bleeding. Hemodynamics were stabilized with angioembolization in 2 patients with prolonged hematuria in group 1. The overall success and complication rates were similar in both groups. Conclusion: Although the postoperative hemoglobin drop did not significantly differ between groups, hemorrhaging was more severe in patients with anterior caliceal stones than in those with posterior caliceal stones.
    Urologia Internationalis 01/2013; · 1.07 Impact Factor
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    ABSTRACT: Objectives. To determine when emergent intervention for bleeding after percutaneous nephrolithotomy (PCNL) is required. Methods. We reviewed analysis data of 850 patients who had undergone PCNL in our center. Blood transfusion was needed for 60 (7%) patients during and/or after surgery. We routinely performed followup of the urine output per hour, blood pressure, and hemoglobin levels after PCNL. Five (0.6%) of them had severe bleeding that emergent intervention was needed. Results. The mean age of the 5 patients who had emergent surgery due to severe bleeding was 42.2 (19-56) years. Mean duration of surgery was 44.75 (25-65) minutes. Mean stone size was 27 (15-38) mm. Mean decrease of hemoglobin was 4.8 (3.4-5.8) ng/dL, and unit of transfused blood was 4.4 (3-6). Mean blood pH was 7.21. There were metabolic acidosis and anuria/oliguria in all these patients. One of 5 patients suffered from cardiopulmonary arrest because of massive bleeding four hours after the PCNL, and despite cardiac resuscitation, he died. Hemorrhaging was controlled by open surgery in the other 4 patients. Two patients experienced cardiac arrest during the open surgery but they responded to cardiac resuscitation. There were no metabolic asidosis and anuria/oliguria, and bleeding was managed only with blood transfusion for the other 55 patients. Conclusion. Severe bleeding after PCNL is rare and can be mortal. If metabolic asidosis and anuria/oliguria accompanied the drop of hemoglobin, emergent surgical intervention should be performed because vascular collapse may follow, and it may be too difficult to stabilise the patient.
    ISRN urology. 01/2013; 2013:760272.
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    ABSTRACT: A 28-year old man presented with left flank pain and dysuria. Plain abdominal film and computed tomography showed a left giant ureteral stone measuring 11.5 cm causing ureteral obstruction and other stones 2.5 cm in size in the lower pole of ipsilateral kidney and 7 mm in size in distal part of right ureter. A left ureterolithotomy was performed and then a double J stent was inserted into the ureter. The patient was discharged from the hospital 4 days postoperatively with no complications. Stone analysis was consistent with magnesium ammonium phosphate and calcium oxalate. Underlying anatomic or metabolic abnormalities were not detected. One month after surgery, right ureteral stone passed spontaneously, left renal stone moved to distal ureter, and it was removed by ureterolithotomy. Control intravenous urography and cystography demonstrated unobstructed bilateral ureter and the absence of vesicoureteral reflux.
    Case Reports in Medicine 01/2013; 2013:236286.
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    ABSTRACT: OBJECTIVES: To compare the outcomes of shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PNL), and retrograde intrarenal surgery (RIRS) for 10-20 mm radiolucent renal calculi by evaluating stone-free rates and associated complications. PATIENTS AND METHODS: A total of 437 patients at 7 institutions who underwent SWL (n = 251), PNL (n = 140), or RIRS (n = 46) were enrolled in our study. Clinical success was defined as stone-free status or asymptomatic insignificant residual fragments <3 mm. The success rates, auxiliary procedures, and complications were compared in each group. RESULTS: Success rates were 66.5, 91.4, and 87 % for SWL, PNL, and RIRS (p < 0.001). The need for auxiliary procedures was more common after SWL than PNL and RIRS (21.9 vs 5.7 vs 8.7 %, respectively; p < 0.001). The overall complication rates for the SWL, PNL, and RIRS were 7.6, 22.1, and 10.9 %, respectively (p < 0.001). Thirteen patients in PNL group received blood transfusions, while none of the patients in RIRS and SWL groups transfused. Hospitalization time per patient was 1.3 ± 0.5 days in the RIRS group, while it was 2.6 ± 0.9 days in the PNL group (p < 0.001). Fluoroscopy and operation time were significantly longer in the PNL group compared to RIRS (145.7 ± 101.7 vs 28.7 ± 18.7 s, and 57.5 ± 22.1 vs 43.1 ± 17 min, respectively). CONCLUSIONS: For treatment of moderate-sized radiolucent renal stones, RIRS and PNL provide significantly higher success and lower retreatment rate compared with SWL. Although PNL is effective, its biggest drawback is its invasiveness. Blood loss, radiation exposure, hospital stay, and morbidities of PNL can be significantly reduced with RIRS technique.
    World Journal of Urology 11/2012; · 2.89 Impact Factor
  • Pediatric Surgery International 11/2012; · 1.22 Impact Factor
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    ABSTRACT: PURPOSE: Our aim was to shed light on forgotten ureteral stents (FUS) neglected issue by presenting the outcomes of a multicentered study in pediatric age group. MATERIALS AND METHODS: Between January 2007 and March 2012, a total of 22 patients with unintentionally forgotten in situ encrusted DJ stents were treated at four centers. Stone burdens were estimated both on plain radiography and computerized tomography. Treatment decision was made based on clinical and radiological findings or stone burden. RESULTS: Nine girls and 13 boys with a mean age of 9.5 (range: 2-16 yrs) years were analyzed. Mean indwelling time of ureteral stents was 21.7 months (6-60 months). Stents were inserted with the indications of urolithiasis (n=17), and reconstructive urological interventions (n=5). In 2 patients DJSs had been placed bilaterally. Mean stent stone burden were 184 mm2 on plain radiography, and 247 mm2 on computerized tomography with a statistically significant difference between them (p=0.002). Shock wave lithotripsy was done in 6 cases. Endoscopic procedures were performed in all patients as follows: ureteroscopy= 8, simple stent stent removal= 7, endoscopic cystolithotripsy = 6, percutaneous nephrolithotomy= 5, retrograde intrarenal surgery=3, and percutaneous cystolithotripsy= 2. Surgical removal of each stent required a mean 1.5 interventions with a mean hospital stay of 4.4 days. CONCLUSIONS: Even in the pediatric age group, in experienced centers, combined endourologic techniques can achieve successful and safe management of forgotten stents. We think that routine preoprocedural tomography is a must in children with FUS.
    The Journal of urology 09/2012; · 4.02 Impact Factor
  • Berkan Resorlu, Ali Unsal, Handan Gulec, Derya Oztuna
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    ABSTRACT: To investigate the prognostic factors associated with the treatment efficacy of retrograde intrarenal surgery (RIRS) and develop a scoring system for predicting the stone-free rate after this surgery. We performed a retrospective analysis of 207 patients who underwent RIRS for renal stones between January 2009 and September 2011. Patient age, gender, body mass index, stone size, stone side, stone location, stone composition, number of stones, lower pole infundibulopelvic angle, using anticoagulant therapy, abnormal skeletal anatomy, and abnormal renal anatomy were investigated as potential preoperative predictive factors. The present study included 111 (53.6%) men and 96 (46.4%) women. Mean patient age was 32.9 ± 18.8 years (range 1-74) and mean stone size was 16.2 ± 4.1 mm (range 8-40). Overall, 178 of the 207 (86%) patients were stone free after the initial treatment. Univariate analysis showed that stone size (P <.001), stone location (P = .025), stone composition (P = .01), stone number (P = .049), renal malformations (P = .042), and lower pole infundibulopelvic angle (P = .003) had significant influence on the stone-free rate after RIRS. Multivariate analysis excluded stone location from the logistic regression model, whereas other factors maintained their statistically significant effect on success rate, indicating that they were independent predictors. Our study demonstrated that stone size, stone number, stone composition, infundibulopelvic angle, and renal malformations are significant predictors of RIRS outcome. A scoring system based on these factors helps separate patients into outcome groups and facilitates treatment planning.
    Urology 07/2012; 80(3):512-8. · 2.42 Impact Factor
  • Article: Reply.
    Berkan Resorlu, Ali Unsal
    Urology 07/2012; 80(3):518. · 2.42 Impact Factor
  • Berkan Resorlu, Ali Unsal
    BJU International 07/2012; 110(2):E5. · 3.05 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: To compare the outcomes of miniaturized percutaneous nephrolithotomy (mini-perc) and retrograde intrarenal surgery (RIRS) in children for 10- to 30-mm renal calculi by evaluating operative data, stone-free rates, and associated complications. The records of 201 pediatric patients who underwent mini-perc (n = 106) or RIRS (n = 95) for intrarenal stones of 10- to 30-mm size were reviewed retrospectively. The χ(2) test was applied to compare the success rates, postoperative complications, and blood transfusion rates, and the Mann-Whitney U test was used to compare the means of hospital stay, fluoroscopy, and operative time for mini-perc and RIRS. The stone-free rate was 84.2% for the RIRS group and 85.8% for the mini-perc group after a single procedure (P = .745). These percentages increased to 92.6% and 94.3% with adjunctive therapies for RIRS and mini-perc, respectively. Minor complications classified as Clavien I or II occurred in 17% and 8.4% in mini-perc and RIRS, respectively. No major complications (Clavien III-V) occurred in either group. Overall complication rates in mini-perc were higher, but the differences were not statistically significant (P = .07). However, 7 patients in the mini-perc group received blood transfusions, whereas none of the children in the RIRS group were transfused (P = .015). The mean hospital stay, fluoroscopy, and operation times were significantly longer in the mini-perc group. This study demonstrates that RIRS is an effective alternative to mini-perc in pediatric patients with intermediate-sized renal stones. Operative time, radiation exposure, hospital stay, and morbidities of percutaneous nephrolithotomy (PNL) can be significantly reduced with the RIRS technique.
    Urology 06/2012; 80(3):519-23. · 2.42 Impact Factor

Publication Stats

233 Citations
127.25 Total Impact Points


  • 2013
    • Bezmiâlem Vakif Üniversitesi
      • Faculty of Medicine
      İstanbul, Istanbul, Turkey
    • Ataturk University
      • Faculty of Medicine
      Kalikala, Erzurum, Turkey
  • 2012–2013
    • Çanakkale Onsekiz Mart Üniversitesi
      • Faculty of Medicine
      Çanakkale, Canakkale, Turkey
  • 2009–2011
    • T.C. Sağlık Bakanlığı Ankara Eğitim ve Araştırma Hastanesi
      Engüri, Ankara, Turkey
    • Ankara Numune Training and Research Hospital
      Engüri, Ankara, Turkey
  • 2006–2011
    • Ankara University
      • Department of Urology
      Ankara, Ankara, Turkey