Paulo Mota

Ureteroscopy-assisted Percutaneous Kidney Access Made Easy: First Clinical Experience with a Novel Navigation System Using Electromagnetic Guidance (IDEAL Stage 1)

BACKGROUND Puncture of the renal collecting system represents a challenging step in percutaneous nephrolithotomy (PCNL). Limitations related to the use of standard fluoroscopic-based and ultrasound-based maneuvers have been recognized. OBJECTIVES To describe the technique and early clinical outcomes of a novel navigation system for percutaneous kidney access. DESIGN, SETTING, AND PARTICIPANTS This was a proof-of-concept study (IDEAL phase 1) conducted at a single academic center. Ten PCNL procedures were performed for patients with kidney stones. SURGICAL PROCEDURE Flexible ureterorenoscopy was performed to determine the optimal renal calyx for access. An electromagnetic sensor was inserted through the working channel. Then the selected calyx was punctured with a needle with a sensor on the tip guided by real-time three-dimensional images observed on the monitor. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The primary endpoints were the accuracy and clinical applicability of the system in clinical use. Secondary endpoints were the time to successful puncture, the number of attempts for successful puncture, and complications. RESULTS AND LIMITATIONS Ten patients were enrolled in the study. The median age was 47.1 yr (30-63), median body mass index was 22.85kg/m2 (19-28.3), and median stone size was 2.13cm (1.5-2.5cm). All stones were in the renal pelvis. The Guys stone score was 1 in nine cases and 2 in one case. All 10 punctures of the collecting system were successfully completed at the first attempt without X-ray exposure. The median time to successful puncture starting from insertion of the needle was 20 s (range 15-35). No complications occurred. CONCLUSIONS We describe the first clinical application of a novel navigation system using real-time electromagnetic sensors for percutaneous kidney access. This new technology overcomes the intrinsic limitations of traditional methods of kidney access, allowing safe, precise, fast, and effective puncture of the renal collecting system. PATIENT SUMMARY We describe a new technology allowing safe and easy puncture of the kidney without radiation exposure. This could significantly facilitate one of the most challenging steps in percutaneous removal of kidney stones.

Video-Based Surgical Learning: Improving Trainee Education and Preparation for Surgery

BACKGROUND Since the end of the XIX century, teaching of surgery has remained practically unaltered until now. With the dawn of video-assisted laparoscopy, surgery has faced new technical and learning challenges. Due to technological advances, from Internet access to portable electronic devices, the use of online resources is part of the educational armamentarium. In this respect, videos have already proven to be effective and useful, however the best way to benefit from these tools is still not clearly defined. AIMS To assess the importance of video-based learning, using an electronic questionnaire applied to residents and specialists of different surgical fields. METHODS Importance of video-based learning was assessed in a sample of 141 subjects, using a questionnaire distributed by a GoogleDoc online form. RESULTS We found that 98.6% of the respondents have already used videos to prepare for surgery. When comparing video sources by formation status, residents were found to use Youtube significantly more often than specialists (p < 0.001). Additionally, residents placed more value on didactic illustrations and procedure narration than specialists (p < 0.001). On the other hand, specialists prized surgeons technical skill and the presence of tips and tricks much more than residents (p < 0.001). CONCLUSION Video-based learning is currently a hallmark of surgical preparation among residents and specialists working in Portugal. Based on these findings we believe that the creation of quality and scientifically accurate videos, and subsequent compilation in available video-libraries appears to be the future landscape for video-based learning.

MP45-09 EFFECTS OF CASTRATION AND TESTOSTERONE REPLACEMENT OVER SEROTONIN (PROSTATIC AND PLASMATIC): A MICE IN VIVO STUDY.

Here, we hypothesized that modulating the plasmatic levels of 5-HT through a tryptophan-rich diet we could inhibit prostatic growth. METHODS: C57BL6 adult male mice were divided in 2 groups, Group 1: fed with a normal diet and Group 2: fed with, for a 3-month period. After the sacrifice of the mice, the prostate was dissected and weighted. By ELISA, prostatic 5-HT concentration was determined and by Western Blot, AR expression was evaluated in both groups. RESULTS: We observed that mice fed with a tryptophan-rich diet for 3 months present a significant reduction in the prostatic weight comparatively to mice fed with normal diet (fig1). Intra-prostatic 5-HT concentration was significantly increased in mice fed with a tryptophanrich diet (fig2). Furthermore, we demonstrated that the expression of AR in prostatic tissue from mice who underwent tryptophan supplementation was inferior to the AR expression in the normal diet group (fig3). CONCLUSIONS: Modulating diet through tryptophan enrichment, with the consequent increase in prostatic serotonin, decreases prostate size and down-regulates AR. These results suggests that a tryptophan rich diet could be potential used to prevent or treat BPH.

MP17-14 DEPLETION OF PERIPHERAL SEROTONIN SYNTHESIS INDUCES BENIGN PROSTATIC GROWTH IN MICE: MORE EVIDENCE FOR THE NEW “NEUROENDOCRINE THEORY” IN BPH ETIOLOGY

up-regulated collagen 1 and aSMA protein expression in response to IL-4 or IL-13 treatment. These effects were ablated through co-treatment with IL-4 and IL-13 receptors antibodies. Low concentrations of IL-4 and IL-13 significantly up-regulated N1 and primary prostate cell proliferation. Prostate fibroblasts treated with IL-4 or IL-13 significantly and almost equivalently up-regulated IL-13 protein expression, suggesting the establishment of an autocrine IL-13 expression loop. Treatment with IL-4 alone up-regulated IL-4, but not IL-13, protein expression. Neither IL-4 nor IL-13 affected TGFbeta expression levels. CONCLUSIONS: The results of these studies show that IL-4 and IL-13 promote myofibroblast phenoconversion and collagen accumulation, and thus support a role for IL-4/IL-13 promotion of prostatic fibrosis associated with LUTD. A major new discovery reported here is that Th2 cytokines, particularly IL-13, can establish autocrine expression loops in prostate fibroblasts that may promote continual myofibroblast phenoconversion in the lower urinary tract. These findings support the investigation of small molecules or antibodies that target Th2 IL-4/IL13 activities for the prevention or treatment of lower urinary tract fibrosis.

V5-10 EXTRAPERITEONAL SIMPLE PROSTATECTOMY: A SURGERY FOR BEGINNERS?

RESULTS: After initial inspection of the bladder demonstrated asymptomatic ureteroceles, an incision was made at the bladder neck and carried to the depth of the surgical capsule distally to the verumontanum. The lateral dissection expresses purulence almost immediately and a large abscess pocket is encountered during the anterior dissection. The remainder of the enucleation is performed without complication. The patient was spontaneously voiding by POD 2 and discharged with IV antibiotics for 6 weeks to treat his osteomyelitis. CONCLUSIONS: Holmium laser enucleation of a prostatic abscess can be performed safely and effectively to both maximally reduce the abscess cavity and risk of excessive thermal injury when treating an apically located abscess.

Serotonin regulates prostate growth through androgen receptor modulation

Aging and testosterone almost inexorably cause benign prostatic hyperplasia (BPH) in Human males. However, etiology of BPH is largely unknown. Serotonin (5-HT) is produced by neuroendocrine prostatic cells and presents in high concentration in normal prostatic transition zone, but its function in prostate physiology is unknown. Previous evidence demonstrated that neuroendocrine cells and 5-HT are decreased in BPH compared to normal prostate. Here, we show that 5-HT is a strong negative regulator of prostate growth. In vitro, 5-HT inhibits rat prostate branching through down-regulation of androgen receptor (AR). This 5-HT’s inhibitory mechanism is also present in human cells of normal prostate and BPH, namely in cell lines expressing AR when treated with testosterone. In both models, 5-HT’s inhibitory mechanism was replicated by specific agonists of 5-Htr1a and 5-Htr1b. Since peripheral 5-HT production is specifically regulated by tryptophan hydroxylase 1(Tph1), we showed that Tph1 knockout mice present higher prostate mass and up-regulation of AR when compared to wild-type, whereas 5-HT treatment restored the prostate weight and AR levels. As 5-HT is decreased in BPH, we present here evidence that links 5-HT depletion to BPH etiology through modulation of AR. Serotoninergic prostate pathway should be explored as a new therapeutic target for BPH.