Orhan Tanriverdi

Bezmiâlem Vakif Üniversitesi, İstanbul, Istanbul, Turkey

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Publications (37)62.66 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: To compare the efficacy of laparoscopic and open ureterolithotomy in patients withureteral stones. Materials and Methods: Patients who had undergone open or laparoscopic ureterolithotomy between 2001 and 2013 in our clinic were enrolled in the study.Ureterolithotomy was performed due to the following reasons: failure to position the patient for ureteroscopy,unreachable stone with ureteroscopy also use of balloon dilatation, high stone volume, and the need for removal of kidney stones at the same session.. The patients' demographic data, the volume of the stones, the duration of the operation and the hospital stay, the amount of analgesics administered after the operation, and the need for another procedure were compared. Results: Of study subjects 32 patients had undergone open and 20 patients had undergone laparoscopic ureterolithotomy. When the two groups were compared, there was no statistically significant difference with regard to the mean age (44.5-44 years), the body mass index (26-24.7 kg/m²), the stone volume (420-580 mm³), the duration of operation (122-123 min), the need for anotherprocedure and complications. The mean amount of analgesics administered after the operation (3.6 and 1.81 doses, P = .02) and the mean hospital stay (6.1 and 2.9 days, P = .01) were significantly lower in the laparoscopic ureterolithotomy group. Conclusion: Laparoscopic ureterolithotomy is a good alternative with less need for analgesia and a shorter hospital stay when compared with open ureterolithotomy.
    Urology journal 01/2014; 11(2):1423-8. · 0.56 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 purposes of our study were to investigate the feasibility of diffusion-weighted imaging in the detection of malignant bladder tumors, with comparison to the high-resolution thin-section fast spin-echo (FSE) T2-weighted MRI, and also to compare the apparent diffusion coefficient (ADC) values of the bladder tumors with the surrounding structures. Fifty-three consecutive patients consisting of 44 males and 9 females who presented with a bladder mass were prospectively enrolled in this study. Mean age was 62.53±12.03 (age range, 33-86 years). These patients were evaluated by high-resolution thin-section FSE T2-weighted and diffusion-weighted MRI for the detection of bladder masses. Following MRI, within 2 weeks, all patients were subjected to either surgery or cystoscopic biopsy, and the obtained histopathological proofs were used as the reference standard. Furthermore, ADC values of the bladder tumors, urine, the normal bladder wall, the central and peripheral zones of the prostate, the seminal vesicule, and the uterus outer myometrium were also calculated. ADC values of the bladder carcinomas and the related surrounding structures were compared as to whether a statistically significant difference was present or not. In a total of 47 patients, consisting of 39 males and 8 females, bladder carcinomas were clearly shown as having conspicuous high and intermediate signal intensity masses, relative to the surrounding structures on diffusion-weighted and T2-weighted images, respectively. An 89% sensitivity and a 100% positive predictive value were obtained for both FSE T2-weighted and diffusion-weighted MRI in the diagnosis of bladder carcinoma. Mean ADC values and standard deviations of the bladder tumors and the surrounding structures were as follows: bladder carcinomas (n=47): 1.28±0.31, normal bladder wall (n=47): 1.98±0.41, urine (n=47): 3.12±0.24, seminal vesicle (n=39): 1.82±0.33, peripheral zone of prostate (n=39): 1.80±0.29, central zone of prostate (n=39): 1.55±0.33, and uterus outer myometrium (n=8): 1.53±0.19. It can be clearly seen that the mean ADC values of the bladder carcinomas were significantly lower than the surrounding structures (P<.05). CONCLUSıON: High-resolution thin-section FSE T2 and diffusion-weighted MRI show high diagnostic performance and are comparable in the detection of bladder tumors. Diffusion-weighted MRI provides high quality images of the malignant bladder tumors against a suppressed background signal. Diffusion-weighted MRI using ADC measurements may be useful in the evaluation of tumor invasion to the adjacent organs.
    Clinical imaging 07/2013; · 0.73 Impact Factor
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    ABSTRACT: To revise the predictive factors for intra-operative complications of rigid ureteroscopy in the treatment of ureteral calculi. During a 15-year period (1993 to 2008), a total of 1496 consecutive patients who had undergone 1660 ureteroscopy procedures were retrospectively reviewed. After exclusion of the cases for diagnostic purposes, diseases other than ureteral calculi, and repeated ureteroscopy procedures, 1189 patients were left as the study population. Those patients were then divided into two groups based on the presence of the complications: complication-positive (group 1, n = 57) and complication-negative (group 2, n = 1132). Both groups were statistically compared regarding patients' age and gender, stone surface area, lateralization and localization of the stone, impaction of the stone, type of the ureteroscope, necessity of ureteral orifice dilation, and use of a catheter during and after the procedure. Furthermore, the effect of leaving the fragmented stones in situ small enough to pass spontaneously (break'n'leave) on occurring of the complications has been investigated. The complication rate was recorded as 4.7%. Success rate after a single intervention was 86.3%, whereas increased to 94.1% after ancillary procedures. Stone surface area, lateralization, and type of lithotripter used were comparable between the groups, but impacted stones and the stones located at the upper ureters were associated with significantly increased complication rates. Furthermore, significantly less complication has been observed in cases where we performed break'n'leave. Furthermore, multivariate analysis revealed that stone impaction and failure to adhere to the "break'n'leave" principle were the independent predictors of occurring of the complications. Ureteroscopy is safe and effective in the treatment of ureteral calculi. Careful attention for the patients having a potential for occurrence of the complications and selection of the techniques are of importance for reducing untoward events.
    Urology journal 01/2012; 9(2):457-64. · 0.56 Impact Factor
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    ABSTRACT: To report the long-term follow-up results of patients with Hinman-Allen syndrome (HAS) at our institution. The data from 22 children with HAS were retrospectively analyzed. The patients were followed up every 3-6 months with serial physical examinations, voiding charts, urine culture, postvoid residual urine volume determination, serum creatinine measurement, and urinary imaging. The follow-up time was calculated from the day of the first visit to the day of the latest dimercaptosuccinic acid scan. Urotherapy, pharmacotherapy, clean intermittent catheterization, biofeedback therapy, and surgery were performed sequentially and/or combined, depending on the disease course. Renal deterioration was defined as any presence of a new scar or cortical thinning compared with the findings from the first dimercaptosuccinic acid scan. Upper urinary tract deterioration was defined as the persistence or progression of hydronephrosis on ultrasonography. The mean age at referral was 9.18 ± 3.36 years (range 2-14), and the mean follow-up period was 80.90 ± 19.57 months (range 54-144). Conservative therapy resulted in improvement of the bladder function in 14 patients; however, 8 patients required surgery owing to failure of this approach. Asymptomatic bacteriuria developed in one half of the children (n = 11, 50%), and in 6 (22.7%), ≥1 febrile urinary tract infection developed. None of the patients had upper urinary tract deterioration; however, renal deterioration developed in 3 patients (13.6%). The mean creatinine levels had remained stable at the end of the follow-up. Close follow-up at a single institution and proactive treatment resulted in successful stabilization of HAS in most of our children with HAS.
    Urology 12/2011; 78(6):1397-401. · 2.42 Impact Factor
  • Mesrur Selcuk Silay, Orhan Tanriverdi, Cengiz Miroglu
    Journal of endourology / Endourological Society 11/2011; 26(1):75-6. · 1.75 Impact Factor
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    ABSTRACT: We evaluated factors affecting complication rates of ureteroscopy for pediatric ureteral calculi. 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. 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. 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.
    The Journal of urology 09/2011; 186(3):1035-40. · 4.02 Impact Factor
  • Article: Reply.
    Orhan Tanriverdi, Kemal Sarica
    Urology 09/2011; 78(3):521-2. · 2.42 Impact Factor
  • Orhan Tanriverdi, Kemal Sarica
    Urology 07/2011; 78(1):234-5. · 2.42 Impact Factor
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    ABSTRACT: An experimental study in rats was performed to evaluate the presence and the degree of both tubular apoptotic changes and crystallization at cortical, medullar and papillary regions of the kidney during hyperoxaluric phase and assess the possible protective effects of vitamin E and verapamil on these pathologic changes (particularly in papillary part of the affected kidneys). A total of 32 rats have been included into the study program. Hyperoxaluria was induced by continuous administration of ethylene glycol (0.75%). In addition to hyperoxaluria induction, animals in Groups 2 and 3 did receive a calcium channel-blocking agent (verapamil) and vitamin E, respectively. Histologic alterations of the kidneys including crystal formation together with apoptotic changes were evaluated on days 1, 14 and 28, respectively. Both apoptotic changes and the presence and degree of crystallization were assessed separately in renal cortical region, medulla and particularly papillary parts of the removed kidneys. Although verapamil did well limit the degree of crystal formation and apoptosis and brought it to the same levels observed in control group animals in all parts of the kidneys during intermediate phase, addition of vitamin E was failed to show the same protective effect during both intermediate and late phase evaluations. As demonstrated in our study, the limitation of both crystal deposition and apoptotic changes might be instituted by calcium channel-blocking agents. Clinical application of such agents in the prophylaxis of stone disease might limit the formation of urinary calculi, especially in recurrent stone formers.
    Urological Research 05/2011; 40(1):17-25. · 1.59 Impact Factor
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    ABSTRACT: To comparatively evaluate the efficacy of ureteroscopic stone treatment immediately after the first colic attack and in an electively planned manner. A total of 145 patients underwent semirigid ureteroscopic removal of obstructive ureteral calculi using 2 different approaches (group 1, 69 patients, and group 2, 76 patients). The 69 patients in group 1 were treated with appropriate medical therapy for a period of ≥7 days for colic pain and subsequently underwent either semirigid ureteroscopy or pneumatic lithotripsy in a planned manner. The 76 patients in group 2 underwent semirigid ureteroscopy after the first colic attack. The stone-free status, auxiliary procedures, and complications were evaluated between the 2 groups using the Mann-Whitney U test; for qualitative data, Fisher's exact test was used. Of the 145 patients who underwent semirigid ureteroscopy, the mean stone size was 11.80±3.95 mm and 8.32±2.08 mm in the 2 groups. No patient experienced a major complication during or after the procedure. The stone-free rate was 87% and 90.7% in groups 1 and 2, respectively. The mean readmission rate to the emergency department for the management of a colic attack was 3.03±2.84 in group 1; no patient in group 2 required readmission. Ureteroscopic stone removal immediately after the first colic attack in the cases of obstructive ureteral stones proved to be safe and effective. It has the main advantage of offering both immediate stone fragmentation and the relief of acute onset colic pain causing extreme discomfort.
    Urology 05/2011; 78(3):516-20. · 2.42 Impact Factor
  • European Urology Supplements - EUR UROL SUPPL. 01/2011; 10(7):505-505.
  • European Urology Supplements - EUR UROL SUPPL. 01/2011; 10(7):483-483.
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    ABSTRACT: To evaluate the causes of emergent stent placement during the postoperative early period after uncomplicated ureteroscopy in 23 patients. Of 276 uncomplicated ureteroscopy procedures performed for the management of ureteral calculi, double-J stent placement was necessary on an emergent basis in 23 patients because of intolerable colic pain and extreme patient discomfort. All stents were inserted within 24 hours after the procedure. Of the 23 patients requiring emergent stent placement, 14 were men and 9 were women. The stones had been located in the lower ureter in 11, mid-ureter in 6, and upper ureter in 6 patients. All patients had undergone an uncomplicated procedure with no complication evident either during or immediately after ureteroscopic stone management. The intraoperative findings for the 23 patients revealed extensive edema formation, unrecognized small stones embedded in the edematous ureteral wall, unpassed small fragments gathered at the orifice, obstructing blood clots, and kinking of the ureter. A retrospective evaluation of the operative CD recordings and radiographic findings clearly showed that a longer operative time, repeated access, management of a large stone, impacted calculi with ureteral wall edema, a mildly narrowed ureteral segment, ignored caliceal small calculi, and a recent history of urinary tract infection contributed to the need for postoperative intervention. Ureteral catheterization, at least in the form of overnight stent placement, might prevent the formation of transient ureteral obstruction, with resultant postoperative patient discomfort and colic pain evident in selected cases.
    Urology 10/2010; 77(2):305-8. · 2.42 Impact Factor
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    ABSTRACT: To compare the results of two different ureteroscopes in pediatric ureteroscopy (URS) procedures. Sixty-five consecutive URS procedures in pediatric population (39 males, 26 females) were retrospectively evaluated. The subjects were divided in two groups according to the type of ureteroscope used: Group 1 (n = 32, Wolf 8F) and group 2 (n = 33, ACMI 6.9F). All the procedures performed in both groups were statistically compared regarding patient age, gender, lateralization, complication rates, whether the procedure was diagnostic or therapeutic, and whether a guide-wire was used. Additionally, in cases with ureteral stones, stone clearance rate and the necessity of a stone extractor were also compared between the groups. All data were statistically analyzed using chi-square and t tests, where appropriate. A p value less than 0.05 was considered as significant. Mean age of the groups were comparable (9.44 +/- 4.3 and 8.67 +/- 3.9, p = 0.456). There was no statistically meaningful difference between the groups regarding patients' gender, lateralization rates, whether the procedure was diagnostic or therapeutic, the need for a guide-wire use, and complication rates (p > 0.05). In cases with ureteral stones, both groups exhibited statistically comparable results in stone clearance rates and the use of a stone extractor (p > 0.05). Data on this comparison demonstrated that both ureteroscopy devices in pediatric population can be used safely in URS procedures. Neither the diameter nor the rigidity is significantly affecting the outcomes and success rates <or=8F caliber.
    Pediatric Surgery International 07/2010; 26(7):733-8. · 1.22 Impact Factor
  • Orhan Tanriverdi, Mesrur Selcuk Silay, Cengiz Miroglu
    Journal of endourology / Endourological Society 08/2009; 23(11):1919. · 1.75 Impact Factor
  • European Urology Supplements - EUR UROL SUPPL. 01/2009; 8(4):292-292.
  • European Urology Supplements - EUR UROL SUPPL. 01/2009; 8(8):661-661.
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    ABSTRACT: The purpose of this study was to evaluate the use of virtual cystoscopy performed with multidetector computed tomography (CT) in patients with suspected bladder tumors and histories of bladder carcinoma operation. Thirty-six patients (29 men and 7 women) with a mean age of 66 years (range, 24-88 years) with suspected bladder tumors and histories of bladder carcinoma operation were included in this prospective study. Virtual cystoscopy was performed by 16-slice multidetector CT scanner. The bladder was filled with diluted contrast material solution through a Foley catheter. Then, all patients underwent conventional cystoscopy examination. Two reviewers found 18 lesions detected by virtual cystoscopy by consensus, whereas 19 lesions were depicted by conventional cystoscopy. At virtual and conventional cystoscopies, the conditions of 3 patients, 2 with chronic inflammations and 1 with foreign body reaction, were wrongly diagnosed as tumors. At conventional cystoscopy, one patient's result was wrongly interpreted as normal. In pathologic evaluation, all tumors were diagnosed as transitional cell carcinoma. Bladder tumor can be noninvasively diagnosed using virtual cystoscopy. Use of virtual cystoscopy should be considered inpatients who present with hematuria or have histories of bladder carcinoma operation and are for follow-up because of its lesser complication risk and its being a less invasive, easily applied procedure without need of anesthesia. In the future, owing to the development of the CT technology and image processing technique, virtual cystoscopy may have a part in the detection of bladder cancer.
    Journal of computer assisted tomography 01/2009; 33(6):867-71. · 1.38 Impact Factor
  • European Urology Supplements - EUR UROL SUPPL. 01/2009; 8(8):658-658.

Publication Stats

204 Citations
62.66 Total Impact Points


  • 2013
    • Bezmiâlem Vakif Üniversitesi
      • Faculty of Medicine
      İstanbul, Istanbul, Turkey
  • 2002–2012
    • Sisli Etfal Training and Research Hospital
      • Department of Radiology
      İstanbul, Istanbul, Turkey