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Featured researches published by Veli Yalcin.


The Journal of Urology | 2001

THE EFFICACY OF EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY FOR ISOLATED LOWER POLE CALCULI COMPARED WITH ISOLATED MIDDLE AND UPPER CALICEAL CALCULI

Can Öbek; Bulent Onal; Koray Kantay; Mehmet Kalkan; Veli Yalcin; ARMAˇGAN Öner; Vural Solok; Nejat Tansu

PURPOSE We assess the efficacy of extracorporeal shock wave lithotripsy monotherapy for isolated lower pole nephrolithiasis, and compare it to that for isolated middle and upper caliceal calculi. MATERIALS AND METHODS We treated 714 renal units in 687 patients with isolated caliceal stones using a Lithostar lithotriptor (Siemens Medical Systems, Erlangen, Germany). The stones were localized in the lower, mid and upper calices in 455, 104 and 128 patients, respectively. Stone load was recorded in cm.2. Patients were stratified into 3 groups based on stone burden. The energy and shock waves, use of anesthesia, number of treatment sessions, auxiliary measures and complications were noted. Patients were evaluated with intravenous urogram or plain film of kidneys, ureters and bladder, and ultrasonography when stone-free, or clinically significant residual fragment status, including nonobstructive and noninfectious insignificant fragments 4 mm. or less, was noted at the fluoroscopic control 2 to 4 weeks after the last session. Final clinically significant residual fragment decision was made 10 to 12 weeks after the last session. Extracorporeal shock wave lithotripsy was considered a failure if no fragmentation was noted after session 3 and continued if fragmentation was noted. Results regarding caliceal localization were compared. RESULTS Complete data were available on 591 renal units. Auxiliary procedures were used in 81 (14%) units before treatment. Anesthesia was given to 101 (17%) patients. The mean number of shock waves and energy used were 2,022 and 17.4 kV., respectively. The difference in shock wave, energy and treatment rate among 3 caliceal locations reached statistical significance only for energy delivered to the lower and upper calices. The effectiveness quotient of extracorporeal shock wave lithotripsy was 36%, 46% and 41% for lower, middle and upper pole stone disease, respectively (p = 0.4). There was a highly significant correlation between stone-free and re-treatment rates, and stone burden. The overall stone-free rate was 66%, and 63%, 73% and 71% for lower, middle and upper caliceal stones, respectively (p = 0.1). For the group with stones greater than 2 cm.2 overall stone-free rate decreased to 49%, and 53%, 60% and 23% in lower, middle and upper caliceal locations, respectively. Overall, extracorporeal shock wave lithotripsy monotherapy failed in 46 (7.7%) renal units. Steinstrasse developed in 39 (6.5%) patients who were then treated with repeat lithotripsy. CONCLUSIONS Extracorporeal shock wave lithotripsy appears to be successful for management of isolated caliceal stone disease. Treatment efficacy was not significantly different among stones localized in lower, middle and upper poles. We recommend it as the primary treatment of choice for stones less than 2.0 cm.2 in all caliceal locations. Treatment should be individualized for management of caliceal stones greater than 2.0 cm.2 until large prospective randomized trials comparing shock wave lithotripsy and percutaneous nephrolithotomy are available.


The Journal of Urology | 2002

Is Periprostatic Local Anesthesia For Transrectal Ultrasound Guided Prostate Biopsy Associated With Increased Infectious Or Hemorrhagic Complications? A Prospective Randomized Trial

Can Öbek; Bulent Onal; Burak Özkan; Ali Ulvi Önder; Veli Yalcin; Vural Solok

PURPOSE Periprostatic local anesthesia for prostate biopsy requires 2 or more extra needle punctures and injection of the local anesthetic through the highly colonized rectum. To our knowledge we report the first prospective randomized trial to assess the infectious or hemorrhagic complications associated with this method. MATERIALS AND METHODS A total of 100 consecutive patients with sterile urine cultures underwent transrectal ultrasound guided prostate biopsy. They were randomized to receive a periprostatic nerve block or no anesthesia. Patients were evaluated for the amount of rectal and urethral bleeding, and symptoms and signs of infection after biopsy. RESULTS The amount of urethral bleeding was slight and similar in the 2 groups. Rectal bleeding was significantly less in the patients who received anesthesia. High fever (greater than 37.8C) was more frequent in the nerve block group and 2 patients in this group required rehospitalization. Bacteriuria in post-biopsy urine cultures was significantly more common in the anesthesia group. CONCLUSIONS Our results suggest that periprostatic local anesthesia for prostate biopsy does not increase the risk of urethral bleeding. It is associated with a decreased incidence of rectal bleeding, presumably due to decreased patient discomfort. The incidence of bacteriuria was significantly higher in the anesthesia group. High fever and hospitalization due to infectious complications were also more common in the local anesthesia group, although not statistically significant. Prospective randomized trials seem warranted to determine the optimum antibiotic prophylaxis regimen in patients undergoing biopsy with a periprostatic nerve block.


The Journal of Urology | 2011

Factors Affecting Complication Rates of Ureteroscopic Lithotripsy in Children: Results of Multi-Institutional Retrospective Analysis by Pediatric Stone Disease Study Group of Turkish Pediatric Urology Society

Hasan Serkan Dogan; Bulent Onal; Nihat Satar; Cem Aygun; Mesut Piskin; Orhan Tanriverdi; Serhat Gürocak; Levent Mert Gunay; Berk Burgu; Ender Ozden; Oktay Nazli; Erim Erdem; Selcuk Yucel; Aykut Kefi; Deniz Demirci; Nihat Uluocak; Ibrahim Atilla Aridogan; Tahsin Turunc; Veli Yalcin; Mehmet Kilinc; Kaya Horasanli; Mustafa Tan; Tarkan Soygür; Saban Sarikaya; Hakan Kilicarslan; Burak Turna; Hasan Erdal Doruk; Serdar Tekgül

PURPOSE We evaluated factors affecting complication rates of ureteroscopy for pediatric ureteral calculi. MATERIALS AND METHODS We retrospectively evaluated 642 children who underwent ureteroscopy at 16 Turkish centers between 2000 and 2010. Semirigid ureteroscopy was used with various calibers to treat 670 ureteral units in 660 sessions. Complications were evaluated according to the Satava and Clavien classification systems. Univariate and multivariate analyses were done to determine predictive factors affecting complication rates. RESULTS A total of 367 females and 265 males were studied. Mean±SD patient age was 90.2±51.4 months (range 4 to 204). Mean±SD stone size, operative time and postoperative hospital stay were 8.9±4.7 mm, 45.8±23.8 minutes and 1.8±2.8 days, respectively. At a mean±SD followup of 13.3±17.6 months 92.8% of patients were stone-free and efficacy quotient was 90.3%. Complications, which occurred in 8.4% of patients (54 of 642), were intraoperative in 25 (Satava grade I to II in 22), early postoperative in 25 (Clavien grade I to II in 23) and late postoperative in 4 (all grade III). While operative time, age, institutional experience, orifice dilation, stenting and stone burden were statistically significant on univariate analysis, multivariate analysis revealed that operative time was the only statistically significant parameter affecting the complication rate. CONCLUSIONS Semirigid ureteroscopy is effective, with a 90% stone-free rate and efficacy quotient. Most complications are low grade and self-limiting. Our results confirm that prolonged operative time is an independent predictor of complications, and should be considered when choosing and performing the treatment modality.


International Urology and Nephrology | 2003

Relation between bladder cancer and protein oxidation.

İlker Aydın Yilmaz; Tülay Akçay; Ufuk Çakatay; Aysegul Telci; Süleyman Ataus; Veli Yalcin

DNA, protein oxidation and lipid peroxidation possess a major impact in carcinogenesis. Also, inflammatory and oxidative events have remarkable importance in bladder cancer. Thus, in this study total protein, protein carbonyl, nitrotyrosine, thiol residues, non-protein thiols, lipid peroxidation, and also, because of their relations to the above parameters, iron and iron binding levels have been investigated in patients with bladder cancer and in control group. Statistical evaluation of the results demonstrated significantly lower plasma protein levels in the patients with bladder cancer, as compared to the healthy control group. Serumiron levels in patients with invasive bladdercancer were found to be significantly lowerwhen compared with non-invasive group. Proteincarbonyl groups were remarkably higher inbladder cancer patients than in healthycontrols. Patients with bladder cancer weredemonstrated to have significantly lower levelsof total thiol groups and protein-bound thiolgroups as compared to healthy controls.Protein-bound thiol groups in patients withinvasive bladder cancer revealed a moresignificant decline, than in non-invasivegroup.


Urologia Internationalis | 2003

Increased Formation of 8-Hydroxy-2’-Deoxyguanosine in Peripheral Blood Leukocytes in Bladder Cancer

Tülay Akçay; Ilker Saygılı; Gülnur Andican; Veli Yalcin

Introduction: Reactive oxygen species-induced damage to DNA plays a major role in carcinogenesis. Methods: In order to estimate the level of oxidative damage in bladder cancer, 8-hydroxy-2′-deoxyguanosine (8-OHdG) was determined in DNA isolated from peripheral blood leukocytes of healthy adults and patients with superficial transitional cell carcinoma. Patients with transitional cell carcinoma of the bladder and control individuals were similar in age. In this study, the level of 8-OHdG in DNA in male subjects was measured by the high-performance liquid chromatography-electrochemical detector method. Results: The 8-OHdG levels in DNA from leukocytes of bladder cancer patients were significantly higher than those in controls. Conclusion: Reduction of oxidative stress is thought to be a very important measure for primary prevention of bladder cancer.


The Journal of Urology | 2014

Factors Affecting Complication Rates of Percutaneous Nephrolithotomy in Children: Results of a Multi-Institutional Retrospective Analysis by the Turkish Pediatric Urology Society

Bulent Onal; Hasan Serkan Dogan; Nihat Satar; Cenk Yucel Bilen; Ali Güneş; Ender Ozden; Ahmet Ozturk; Deniz Demirci; Okan Istanbulluoglu; Serhat Gürocak; Oktay Nazli; Orhan Tanriverdi; Aykut Kefi; Esat Korgali; Mesrur Selcuk Silay; Kubilay Inci; Volkan Izol; Ramazan Altintas; Hakan Kilicarslan; Saban Sarikaya; Veli Yalcin; Cem Aygun; Fetullah Gevher; Ibrahim Atilla Aridogan; Serdar Tekgül

PURPOSE We assessed factors affecting complication rates of percutaneous nephrolithotomy in children. MATERIALS AND METHODS We retrospectively evaluated data on 1,205 renal units in 1,157 children treated with percutaneous nephrolithotomy at 16 Turkish centers between 1991 and 2012. Of the patients 28.3% had a history of urolithiasis. Complications were evaluated according to the Satava classification system and modified Clavien grading system. Univariate and multivariate analyses were done to determine predictive factors affecting complication rates. RESULTS A total of 515 females and 642 males were studied. Mean ± SD patient age was 8.8 ± 4.7 years (range 4 months to 17 years). Mean ± SD stone size, operative time and postoperative hospital stay were 4.09 ± 4.06 cm(2), 93.5 ± 48.6 minutes and 5.1 ± 3.3 days, respectively. Postoperative stone-free rate was 81.6%. A total of 359 complications occurred in 334 renal units (27.7%). Complications were intraoperative in 118 cases and postoperative in 241. While univariate analysis revealed that stone history, positive urine culture, operative time, length of hospitalization, treatment success, punctured calyx and location of the stone significantly affected the complication rates (p <0.05), operative time, sheath size, mid calyceal puncture and partial staghorn formation were the statistically significant parameters affecting complication rates on multivariate logistic regression analysis. CONCLUSIONS Percutaneous nephrolithotomy is the treatment of choice for most renal calculi in children. The technique is effective and safe in children, with a high success rate and a low rate of major complications. The significant factors identified should be considered by clinicians to decrease associated complication rates.


Urologia Internationalis | 2003

Outcome of Nephron-Sparing Surgery: Elective versus Imperative Indications

Ali Riza Kural; Oktay Demirkesen; Bulent Onal; Can Öbek; Burcin Tunc; Ali Ulvi Önder; Veli Yalcin; Vural Solok

Introduction: The increase in the detection of renal tumors incidentally in earlier stages has enhanced the enthusiasm for nephron-sparing surgery (NSS). Patients and Methods: We performed NSS in 76 patients (53 male, 23 female) with a mean age 52.3 between December 1988 and September 2001. Patients were sub-classified into 2 groups as elective or imperative indication group. They were compared regarding surgical technique, time of surgery, pathological analysis, complications, and disease free status. Results: Elective indication group (group I) with a normal contralateral kidney consisted of 50 patients, whereas there were 26 patients in the imperative indication group (group II). Tumors were incidentally detected in 63%; 74% in group I and 42% in group II. Although the mean diameter of the tumor was slightly higher in group II (39.1 vs. 36.3 mm), this difference did not reach statistical significance (p > 0.05). The partial nephrectomy was performed more frequently compared to enucleation in group I (90 vs. 69%, p = 0.050). However, the mean operation time as well as the mean clamping time did not differ significantly between the two groups (p > 0.05). In the histological evaluation tumors were benign in 16 (21%) and malignant in 60 patients. All of the patients but one with renal cell carcinoma had stage T1-T2 disease. Major complications were observed in 14 (18%) and 12 were from group II. Complication rate was significantly higher in group II (p = 0.000). Of 60 patients with renal cell carcinoma, 2 died of unrelated causes. One patient died with multiple visceral metastases. One patient was lost to follow-up. In the remaining 56 patients with a mean follow-up of 37.1 months (1–152), local recurrence or distant metastases were not detected. Serum creatinine levels have remained almost the same compared to preoperative levels (1.2 ± 0.6 vs. 1.5 ± 0.9). Overall and cancer-specific survivals were 100 and 100% in group I, 85 and 95% in group II, and 94 and 98% for the entire patient population, respectively. Conclusion: NSS is an effective and reliable treatment in low stage renal tumors. It prevents unnecessary nephrectomy in benign lesions that could not be diagnosed preoperatively. However, the patients who underwent NSS with elective indication outcome with better results, compared to those with imperative indication.


Urologia Internationalis | 1998

An unusual presentation of a foreign body in the urinary bladder : A migrant intrauterine device

Veli Yalcin; Oktay Demirkesen; Bulent Alici; Bülent Önol; Vural Solok

A 35-year-old woman, who had had an intrauterine device inserted 7 years earlier, presented with dysuria, pollakiuria, suprapubic pain and urethral irritation. The intrauterine device was found in the bladder with stone formation and was removed by endoscopy.


The Journal of Urology | 2010

Is Prophylactic Breast Radiotherapy Necessary in All Patients With Prostate Cancer and Gynecomastia and/or Breast Pain?

Haluk Ozen; Fadil Akyol; Gokhan Toktas; Saadettin Eskicorapci; Erdinc Unluer; Uğur Kuyumcuoğlu; Erkan Abay; Ibrahim Cureklibatur; Meric Sengoz; Veli Yalcin; Haluk Akpinar; Ferruh Zorlu; Feridun Sengor; Ihsan Karaman

PURPOSE We investigated the efficacy of prophylactic radiotherapy for gynecomastia/breast pain induced by 150 mg bicalutamide in a prospective, randomized, multi-institutional trial. MATERIALS AND METHODS After definitive treatment for localized prostate cancer 125 patients were randomized to 12 Gy radiotherapy before bicalutamide as prophylactic radiotherapy (53) or bicalutamide only for nonprophylactic radiotherapy (72). The incidence of gynecomastia, breast pain and tenderness, and discomfort perceived by the patients was assessed by physical examination and direct questioning at 3, 6 and 12 months of followup. RESULTS At the end of 12 months the gynecomastia rate was 15.8% in the prophylactic group and 50.8% in the nonprophylactic group (p <0.001). On patient evaluation the breast enlargement rate was 34.4%. The severity of breast pain and tenderness was not different between the groups. The breast pain rate was 36.4% and 49.2% by 12 months in the prophylactic and nonprophylactic groups, and the rate of patients who felt discomfort from gynecomastia was 11.4% and 29.5%, respectively. CONCLUSIONS In this prospective study the incidence of gynecomastia was not as high as previously believed. Although prophylactic breast irradiation seemed to decrease the gynecomastia rate in patients on 150 mg bicalutamide, our study proves that not all patients need prophylaxis since only 52% were significantly bothered by gynecomastia. Thus, individual assessment is needed to select patients who need prophylactic radiation while on 150 mg bicalutamide.


Urologia Internationalis | 2000

A Case of Metastatic Malignant Melanoma Presenting with Hematuria

Oktay Demirkesen; Ozgur Yaycioglu; Nesrin Uygun; Gokhan Demir; Veli Yalcin

We report a case of metastatic malignant melanoma that presented with macroscopic hematuria and lower urinary tract symptoms. Effective palliation of urinary tract symptoms was achieved with transurethral resection of metastatic lesions in the bladder. However, the patient was lost due to widespread disease despite systemic therapy. Solitary or multiple dark blue-black nodular or vegetating lesions encountered during cystoscopy should raise the suspicion of metastasis of malignant melanoma and be investigated accordingly.

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