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Öğe Augmented Reality Visualization During Laparoscopic Radical Prostatectomy(MARY ANN LIEBERT INC, 2011) Simpfendoerfer, Tobias; Baumhauer, Matthias; Mueller, Michael; Gutt, Carsten N.; Meinzer, Hans-Peter; Rassweiler, Jens J.; Guven, SelcukPurpose: We present an augmented reality (AR) navigation system that conveys virtual organ models generated from transrectal ultrasonography (TRUS) onto a real laparoscopic video during radical prostatectomy. By providing this additional information about the actual anatomy, we can support surgeons in their working decisions. This work reports the system's first in-vivo application. Materials and Methods: The system uses custom-developed needles with colored heads that are inserted into the prostate as soon as the organ surface is uncovered. These navigation aids are once segmented in three-dimensional (3D) TRUS data that is acquired right after the placement of the needles and then continuously tracked in the laparoscopic video images by the surgical navigation system. The navigation system traces the navigation aids in real time and computes a registration between TRUS image and laparoscopic video based on the two-dimensional-three dimensional (2D-3D) point correspondences. With this registration, the system correctly superimposes TRUS-based 3D information on an additional AR monitor placed next to the normal laparoscopic screen. Surgical navigation guidance took place until the prostate was removed from the rectal wall. Finally, the navigation aids were removed together with the specimen inside the specimen bag. Results: The initial human in-vivo application of the surgical navigation system was successful. No complications occurred, the prostate was removed together with the navigation aids, and the system supported the surgeons as intended with an AR visualization in real time. In case of tissue deformations, changes in the spatial configuration of the navigation aids are detected, which preserves the system from erroneous navigation visualization. Conclusions: Feasibility of the navigation system was shown in the first in-vivo application. TRUS information could be superimposed via AR in real time. To show the benefit for the patient, results obtained from a larger number of trials are needed.Öğe Augmented Reality: A New Tool To Improve Surgical Accuracy during Laparoscopic Partial Nephrectomy? Preliminary In Vitro and In Vivo Results(ELSEVIER, 2009) Teber, Dogu; Guven, Selcuk; Simpfendoerfer, Tobias; Baumhauer, Mathias; Gueven, Esref Oguz; Yencilek, Faruk; Goezen, Ali SerdarBackground: Use of an augmented reality (AR)-based soft tissue navigation system in urologic laparoscopic surgery is an evolving technique. Objective: To evaluate a novel soft tissue navigation system developed to enhance the surgeon's perception and to provide decision-making guidance directly before initiation of kidney resection for laparoscopic partial nephrectomy (LPN). Design, setting, and participants: Custom-designed navigation aids, a mobile C-arm capable of cone-beam imaging, and a standard personal computer were used. The feasibility and reproducibility of inside-out tracking principles were evaluated in a porcine model with an artificially created intraparenchymal tumor in vitro. The same algorithm was then incorporated into clinical practice during LPN. Interventions: Evaluation of a fully automated inside-out tracking system was repeated in exactly the same way for 10 different porcine renal units. Additionally, 10 patients underwent retroperitoneal LPNs under manual AR guidance by one surgeon. Measurements: The navigation errors and image-acquisition times were determined in vitro. The mean operative time, time to locate the tumor, and positive surgical margin were assessed in vivo. Results and limitations: The system was able to navigate and superpose the virtually created images and real-time images with an error margin of only 0.5 mm, and fully automated initial image acquisition took 40 ms. The mean operative time was 165 min (range: 135-195 min), and mean time to locate the tumor was 20 min (range: 1327 min). None of the cases required conversion to open surgery. Definitive histology revealed tumor-free margins in all 10 cases. Conclusions: This novel AR tracking system proved to be functional with a reasonable margin of error and image-to-image registration time. Mounting the pre- or intraoperative imaging properties on real-time videoendoscopic images in a real-time manner will simplify and increase the precision of laparoscopic procedures. (C) 2009 European Association of Urology Published by Elsevier B.V. All rights reserved.Öğe A COMPARISON OF RECOVERY CHARACTERISTICS OF SEVOFLURANE AND PROPOFOL-REMIFENTANIL ANESTHESIA IN GERIATRIC PATIENTS(GUNES KITABEVI LTD STI, 2011) Celik, Jale Bengi; Topal, Ahmet; Erol, Atilla; Guven, Selcuk; Kara, InciIntroduction: In this study we aimed to compare the recovery characteristics of propofol/remifentanil and sevofluran/remifentanil anesthesia in 100 geriatric patients undergoing urological procedures. Materials and Method: The patients were randomized to receive either propofol-remifentanil (group P) or sevoflurane-remifentanil (Group S) anesthesia. Recovery characteristics, the time to post-anesthetic discharge scoring system (PADSS) score and Aldrete score of 9 point, Digit Symbol Substitution Test (DSST) and Trieger Dot Test (TDT) values were compared between two groups. Results: Extubation time was significantly shorter in group P than in group S (5.3 +/- 2.9 min vs 7.8 +/- 3.8 min, p=0.038). The times of first eye opening, response to verbal commands and orientation were similar in both groups. The time of Aldrete score of 9 points (grup P: 14.2 +/- 3.6 min, group S: 16.3 +/- 4.5 min) and PADSS of 9 points (group P: 19.3 +/- 5.7 min, group S: 22.1 +/- 4.2 min) were also similar (p > 0.05). Time to return to the normal value of DSST was significantly shorter in Group P compared with Group S, and TDT was similar in both groups (p > 0.05). No significant differences were observed in the incidence of postoperative complications and VAS score (p > 0.05). Conclusion: Both propofol-remifentanil and sevoflurane-remifentanil appears to be an adequate anesthesia in geriatric patients.Öğe Laparoscopic hysterectomy and bilateral salpingo-oophorectomy incongenital adrenal hyperplasia(MARY ANN LIEBERT INC, 2006) Klinic, Mehmet; Atabek, Emre; Guven, Selcuk; Pirgon, Ozgur[Abstract not Available]Öğe Penis replantation after self-mutilation(SPRINGER, 2009) Ozturk, Ahmet; Kilinc, Mehmet; Guven, Selcuk; Gormus, Niyazi; Belviranli, Metin; Kaynar, Mehmet; Arslan, MehmetIn this case report, the procedure of penis replanting and its complications after genital self-mutilation in a male adult are explained.Öğe Percutaneous injection sclerotherapy with tetracycline hydrochloride in simple renal cysts(SPRINGER, 2008) Kilinc, Mehmet; Tufan, Osman; Guven, Selcuk; Odev, Kemal; Gurbuz, RecaiObjectives Symptomatic simple renal cysts can be treated by combination of percutaneous aspiration and sclerotherapy. A number of sclerosing agents including glucose, phenol, iophendylate, polidocanol, minocycline and pantopaque have been used in the past to prevent reformation of cyst. In this study, tetracycline HCL solution is evaluated as a sclerosant for treatment of simple renal cysts. Methods Our study treated 76 cysts in 70 patients with symptomatic renal cysts. Aspiration and sclerotherapy was performed on 56 cysts, and 20 cysts aspirated without sclerotherapy as a control group. Treatment was performed under local anesthesia and punctured under ultrasound guidances with an 18-gauge needle. Tetracycline HCL (20%) was injected into the cystic cavity according to cyst diameter. All patients were followed up with an ultrasound examination at 3 months, 6 months, and then at yearly intervals. The reduction rate was estimated by a comparison of the volume of the cyst before and after treatment. A cyst reduction of 50% or greater in diamater was considered as a successful treatment. Results The average follow-up period was 9.8 months in the sclerotherapy group and 9.9 months in the control group. The success rate was 85.7% in the sclerotherapy group. There was a significant difference in the reduction rate of tetracycline HCL sclerotherapy group and control group. No major complications were encountered.Öğe Öğe Simultaneous Bilateral Percutaneous Nephrolithotomy in Children: No Need to Delay(MARY ANN LIEBERT INC, 2011) Guven, Selcuk; Ozturk, Ahmet; Arslan, Mehmet; Istanbulluoglu, Okan; Piskin, Mesut; Kilinc, MehmetBackground and Purpose: Children with bilateral kidney stones are generally treated using staged percutaneous nephrolithotomy (PCNL). Reports related to simultaneous bilateral PCNL (SBPCNL) in children are scarce. We aimed to evaluate the efficacy and safety of SBPCNL in children. Patients and Methods: The children who underwent SBPCNL applications between January 2007 and February 2010 in our clinic were evaluated. Patient data were collected from the retrospective reviews of hospital records. Results: SBPCNL was conducted in five patients for bilateral renal stones. The mean age of the patients was 6.28 years (range 0.75-15 y), and the mean follow-up was 10.6 months (range 1-36 mos). The mean renal stone burden was 19 mm (range 11-22 mm). Four children underwent bilateral standard PCNL, and one child underwent bilateral tubeless PCNL. The mean duration of SBPCNL was 75 minutes (range 55-120 min), and the hospitalization time was 4 days (range 2-5 d). No blood transfusion was necessary in any patient. Except for the patient with complex renal stones, all patients were stone free after the intervention, and none needed a conversion to open surgery. Conclusion: SBPCNL is a safe and effective procedure in children if they are selected properly and if the surgeon has sufficient experience with the procedure. More studies with a higher number of participants are needed, however, for further evaluation of the procedure.Öğe Successful Percutaneous Nephrolithotomy in Children: Multicenter Study on Current Status of its Use, Efficacy and Complications Using Clavien Classification(ELSEVIER SCIENCE INC, 2011) Guven, Selcuk; Istanbulluoglu, Okan; Gul, Umit; Ozturk, Ahmet; Celik, Huseyin; Aygun, Cem; Ozdemir, UmitPurpose: In this multicenter study we aimed to evaluate the efficacy and safety of percutaneous nephrolithotomy in children with respect to different features and using the Clavien classification system. Materials and Methods: Percutaneous nephrolithotomies performed in children at 3 urology departments between March 2006 and May 2010 were included in the study. Results are presented for complex/simple renal stones, tubeless/totally tubeless percutaneous nephrolithotomy, simultaneous bilateral percutaneous nephrolithotomy, instrument size and age groups. Patients were divided into 3 distinct groups, infants and toddlers (3 years or younger, group 1), preschool children (4 to 7 years, group 2) and school children (8 to 16 years, group 3). Perioperative complications are presented according to the modified Clavien classification system. Results: A total of 140 percutaneous nephrolithotomies were performed in 130 patients (41.5% female, mean age 10.17 years). There were 23, 25 and 92 renal units in groups 1, 2 and 3, respectively. Pediatric instruments were used in 60 renal units and adult-sized instruments in 80. General assessment of complications showed Clavien grade I complications in 17 patients, II in 4, IIIa in 11 and IIIb in 7. There were no grade IV or V complications. Conclusions: Percutaneous nephrolithotomy can be applied safely in children of varying ages, even infants. Complications, as assessed with Clavien classification, are comparable to those seen in adults provided there is enough experience with the technique.Öğe Totally Tubeless Percutaneous Nephrolithotomy: Is It Safe and Effective in Preschool Children?(MARY ANN LIEBERT, INC, 2010) Ozturk, Ahmet; Guven, Selcuk; Kilinc, Mehmet; Topbas, Emrah; Piskin, Mesut; Arslan, MehmetBackground and Purpose: After the introduction of tubeless percutaneous nephrolithotomy (PNL), many studies conducted in adult patients have confirmed its efficacy and safety. There are limited studies reporting that tubeless PNL can be safely applied in children, however. Furthermore, there are no reports that evaluate the use of totally tubeless PNL in children. The present study evaluates the results of totally tubeless PNL in preschool children. Patients and Methods: The data of children seen in our clinic who were considered suitable for totally tubeless PNL were analyzed. Of 16 children, 8 patients underwent totally tubeless PNL (group 1) and 8 standard PNL (group 2). The two groups of patients were compared with regard to length of hospitalization, analgesic requirements, transfusion rates, hemoglobin (Hb) decrease, and immediate, early, and late complications. Results: The mean ages of the patients were 56.6 months (9-84 mos) and 56.0 months (5-84 mos), and the mean follow-up was 21.5 months (3-44 mos) and 43.4 months (36-54 mos) in groups 1 and 2, respectively. Both groups were similar with regard to age, stone size, Hb change, and complications. Although operation duration, hospitalization period, and analgesic requirement were less in the totally tubeless PNL group, these differences were not statistically significant. Conclusions: The latest application of PNL, totally tubeless PNL, is also a safe and effective procedure in very small children if they are selected properly and if the surgeon has sufficient experience with the procedure. More studies with a higher number of participants are needed, however, to confirm that totally tubeless PNL increases the comfort of pediatric patients, decreases their hospitalization period, and is more economical.
