Browsing by Author "Rodrigues, PL"
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- Collecting system percutaneous access using real-time tracking sensors: first pig model in vivo experiencePublication . Rodrigues, PL; Vilaça, JL; Oliveira, C; Cicione, A; Rassweiler, J; Fonseca, J; Rodrigues, NF; Correia-Pinto, J; Lima, EPURPOSE: Precise needle puncture of the renal collecting system is a challenging and essential step for successful percutaneous nephrolithotomy (PCNL). This works aims to evaluate the efficiency of a new real-time electromagnetic tracking (EMT) system for in vivo kidney puncture. MATERIALS AND METHODS: Six anesthetized female pigs underwent ureterorenoscopies in order to place a catheter with an EMT sensor into the desired puncture site and to ascertain the success of puncture. Subsequently, a tracked needle with a similar EMT sensor was navigated into the sensor inside the catheter. Four punctures were performed by two surgeons in each pig: one in the kidney and one in the middle ureter, on both right and left pig sides. Number of attempts and time needed to evaluate the virtual trajectory and to perform the percutaneous puncture were outcomes measurements. RESULTS: Overall 24 punctures were easily performed without any complications. Surgeons required more time to evaluate the trajectory during ureteral puncture than kidney (median 15 versus 13 seconds, range 14 to 18 and 11 to 16 seconds, respectively; p= 0.1). The median renal and ureteral puncture time were 19 and 51 seconds respectively (range 14 to 45 and 45 to 67; p=0.003). Two attempts were needed to achieve a successful ureteral puncture. The presented technique demands presence of renal stone for testing. CONCLUSIONS: The proposed EMT solution for renal collecting system puncture proved to be highly accurate, simple and quicker. This method might represent a paradigm shift in percutaneous kidney access techniques.
- Kidney Targeting and Puncturing During Percutaneous Nephrolithotomy: Recent Advances and Future PerspectivesPublication . Rodrigues, PL; Rodrigues, NF; Fonseca, J; Lima, E; Vilaça, JLBACKGROUND AND PURPOSE: Precise needle puncture of the kidney is a challenging and essential step for successful percutaneous nephrolithotomy (PCNL). Many devices and surgical techniques have been developed to easily achieve suitable renal access. This article presents a critical review to address the methodologies and techniques for conducting kidney targeting and the puncture step during PCNL. Based on this study, research paths are also provided for PCNL procedure improvement. METHODS: Most relevant works concerning PCNL puncture were identified by a search of Medline/PubMed, ISI Web of Science, and Scopus databases from 2007 to December 2012. Two authors independently reviewed the studies. RESULTS: A total of 911 abstracts and 346 full-text articles were assessed and discussed; 52 were included in this review as a summary of the main contributions to kidney targeting and puncturing. CONCLUSIONS: Multiple paths and technologic advances have been proposed in the field of urology and minimally invasive surgery to improve PCNL puncture. The most relevant contributions, however, have been provided by the application of medical imaging guidance, new surgical tools, motion tracking systems, robotics, and image processing and computer graphics. Despite the multiple research paths for PCNL puncture guidance, no widely acceptable solution has yet been reached, and it remains an active and challenging research field. Future developments should focus on real-time methods, robust and accurate algorithms, and radiation free imaging techniques.
- Ureteroscopy-assisted Percutaneous Kidney Access Made Easy: First Clinical Experience with a Novel Navigation System Using Electromagnetic Guidance (IDEAL Stage 1)Publication . Lima, E; Rodrigues, PL; Mota, P; Carvalho, N; Dias, E; Correia-Pinto, J; Autorino, R; Vilaça, JLBACKGROUND: 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 Guy's 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.
- Variations of the soft tissue thicknesses external to the ribs in Pectus Excavatum patientsPublication . Rodrigues, PL; Direito-Santos, B; Moreira, AH; Fonseca, JC; Pinho, AC; Rodrigues, NF; Henriques-Coelho, T; Correia-Pinto, J; Vilaça, JLBACKGROUND: Surgical repair of pectus excavatum (PE) has become more popular due to improvements in the minimally invasive Nuss procedure. The pre-surgical assessment of PE patients requires Computerized Tomography (CT), as the malformation characteristics vary from patient to patient. OBJECTIVE: This work aims to characterize soft tissue thickness (STT) external to the ribs among PE patients. It also presents a comparative analysis between the anterior chest wall surface before and after surgical correction. METHODS: Through surrounding tissue segmentation in CT data, STT values were calculated at different lines along the thoracic wall, with a reference point in the intersection of coronal and median planes. The comparative analysis between the two 3D anterior chest surfaces sets a surgical correction influence area (SCIA) and a volume of interest (VOI) based on image processing algorithms, 3D surface algorithms, and registration methods. RESULTS: There are always variations between left and right side STTs (2.54±2.05mm and 2.95±2.97mm for female and male patients, respectively). STTs are dependent on age, sex, and body mass index of each patient. On female patients, breast tissue induces additional errors in bar manual conception. The distances starting at the deformity's largest depression point at the SCIA are similar in all directions. Some diverging measures and outliers were found, being difficult to find similar characteristics between them, especially in asymmetric patients. CONCLUSION: The Nuss procedure metal bar must be modeled according to each patient's special characteristics. The studied relationships between STT and chest surface could represent a step forward to eliminate the CT scan from PE pre-surgical evaluation.