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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 268: 120678, 2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-34902691

RESUMEN

Stable conformers of neutral balenine were scanned through molecular dynamics simulations and energy minimizations using Allinger's MM2 force field. For each of the found minimum-energy conformers, geometry optimization and thermochemistry calculations were performed by using B3LYP, MP2, G3MP2B3 methods, 6-31G(d), 6-311++G(d,p) and aug-cc-pvTZ basis sets. The calculation results have indicated that balenine has about twenty stable conformers whose relative energies are in the range of 0-9.5 kcal/mol. Three of these are thought to provide the major contribution to matrix isolation IR spectra of the molecule. Our solvent calculations using the polarized continuum model revealed the stable zwitterion structures which are predicted to dominate IR spectra of balenine in water and heavy water (D2O) solvents. Pulay's SQM-FF method was used in scaling of the harmonic force constants and vibrational spectral data calculated for the neutral and zwitterion structures. These refined calculation data together with those obtained from anharmonic frequency calculations enabled us to correctly interpret the matrix isolation IR spectrum of balenine and the tautomerism-based changes observed in its KBr IR and solution (D2O) IR spectra. The results revealed the crucial role of conformation and zwitterionic tautomerism on the structure and vibrational spectral data of the molecule.


Asunto(s)
Dipéptidos , Vibración , Conformación Molecular , Espectrofotometría Infrarroja
2.
Urologe A ; 59(10): 1168-1176, 2020 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-32845346

RESUMEN

Herein we describe four clinical scenarios. For the standard patient (prostate volume 30-80 ml, life expectancy >10 years) transurethral resection of the prostate (TURP) remains the standard of care, while endoscopic enucleation is a valuable alternative. Patients with a relevant middle lobe profit most from TURP, endourological enucleation procedures, or laser vaporization. In the case of the absence or a moderate-sized middle lobe and the absence of severe bladder outlet obstruction (BOO), minimally invasive procedures such as Rezum®, UroLift® or prostate artery embolization (PAE) can be offered. Patients have to be informed that long-term data on this specific indication are lacking. Particularly younger men requiring BPH surgery are interested in preserving ejaculatory function. In the presence of severe BOO, ejaculatory-protective TURP or endoscopic enucleation by preserving the pericollicular region or aquablation are the methods of choice providing an antegrade ejaculation in 60-90% of cases. Rezum®, AquaBeam®, and UroLift® enable preservation of ejaculation in almost 100%; data on PAE with this respect are more controversial. For patients with a small prostate and significant post void residual, a thorough preoperative work-up, including urodynamics and bladder/detrusor wall thickness measurement, is of great importance. Desobstructive surgery provides satisfactory short- and midterm outcome, yet the long-term outcome is disappointing and remains to be determined in greater detail. The broad spectrum of therapeutic options enables today an individualized minimally invasive or surgical management of BPH considering patient wishes, anatomical factors or urodynamic factors. The time of a "one therapy fits all" strategy is definitely history.


Asunto(s)
Terapia por Láser , Hiperplasia Prostática , Resección Transuretral de la Próstata , Obstrucción del Cuello de la Vejiga Urinaria , Humanos , Masculino , Hiperplasia Prostática/cirugía , Resultado del Tratamiento , Obstrucción del Cuello de la Vejiga Urinaria/etiología , Obstrucción del Cuello de la Vejiga Urinaria/cirugía
3.
Urologe A ; 58(7): 809-820, 2019 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-31263939

RESUMEN

Both the demographic shift and progress in medicine are resulting in an increasingly longer life expectancy. It is presumed that a mean age of 90 years will be achieved within the next decade in many countries. Thus, geriatric medicine, which is committed to the specific needs of older, often frail and frequently comorbid patients, is becoming increasingly more important. The prevalence of infections of the genitourinary tract increases with age, simultaneously, a critical and conscious use of antibiotics is required in terms of antimicrobial treatment. The intention of the present review is to make the reader aware of the specific characteristics of urinary tract infections and asymptomatic bacteriuria in the older patient population in terms of epidemiology, spectrum of pathogens and resistance as well as the indications for and performance of antimicrobial treatment.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Profilaxis Antibiótica/métodos , Bacteriuria/tratamiento farmacológico , Humanos , Resultado del Tratamiento
5.
Urologe A ; 58(4): 437-450, 2019 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-30923856

RESUMEN

The spectrum of surgical procedures for the minimally invasive treatment of benign prostatic hyperplasia (BPH) has significantly increased over the last two decades. The simple suprapubic prostatectomy (subtotal prostatectomy, SP) has largely lost relevance in current practice. On the other hand, transurethral resection of the prostate (TURP) has been further standardized and potentially made safer by the introduction of the bipolar technique and low-pressure systems.Transurethral (endoscopic) enucleation techniques (endoscopic enucleation of the prostate, EEP) are increasingly competing with the current gold standard TURP and are replacing SP for treatment of larger adenomas. This approach is especially related to the rapid development of laser technology, which has sustainably changed the face of modern BPH treatment in a similar way to stone therapy. This has been incorporated in the clinical patient management, clinical studies and standardization of numerous surgical techniques that are systematically described in this article. Additionally, efforts have also been made to use other energy sources, such as bipolar current in EEP. With respect to scientific objectivity, high-quality clinical trials are regularly published which further strengthen the position of EEP.


Asunto(s)
Terapia por Láser , Hiperplasia Prostática , Resección Transuretral de la Próstata , Endoscopía , Humanos , Masculino , Prostatectomía , Hiperplasia Prostática/terapia
6.
Urologe A ; 57(4): 463-473, 2018 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-29520419

RESUMEN

Interventional treatment of stones essentially consists of three treatment modalities. Extracorporeal shockwave lithotripsy (ESWL), in addition to uterorenoscopy (URS) and percutaneous nephrolitholapaxy (PCNL) is an essential treatment pillar and is the only noninvasive therapy option for the treatment of urinary stones. After a long period of ESWL being the leading choice in stone treatment, the number of SWL interventions diminished in recent years in favor of the other two treatment modalities (URS and PCNL). This article describes the indications, surgical technique and management of complications of SWL.


Asunto(s)
Cálculos Renales/terapia , Litotricia/métodos , Profilaxis Antibiótica , Contraindicaciones , Femenino , Humanos , Masculino , Procedimientos Quirúrgicos Mínimamente Invasivos , Nefrolitotomía Percutánea , Ureteroscopía
7.
Urologe A ; 56(9): 1193-1206, 2017 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-28762032

RESUMEN

Correct positioning of patients during preoperative preparations is essential for success of the intervention to avoid any positioning trauma and to provide the best access to the targeted structures. The appropriate positioning (and optimal performance) means that complications are avoided and also makes an essential contribution to the smooth course of the surgical intervention. A correct position is essential particularly in urology because the organs assigned to the discipline of urology are anatomically mostly difficult to reach. A further important function of the correct positioning technique is the avoidance of injuries to the patient. This article summarizes the most common positioning techniques in urological interventions with special emphasis on the explanation of practical advice, helpful tips and possible complications that can enable even junior surgeons to correctly perform the appropriate positioning technique.


Asunto(s)
Posicionamiento del Paciente/métodos , Enfermedades Urológicas/cirugía , Procedimientos Quirúrgicos Urológicos/métodos , Diseño de Equipo , Femenino , Humanos , Complicaciones Intraoperatorias/prevención & control , Masculino , Mesas de Operaciones , Posicionamiento del Paciente/instrumentación , Complicaciones Posoperatorias/prevención & control , Cuidados Preoperatorios/métodos
8.
Urologe A ; 56(3): 395-404, 2017 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-28243769

RESUMEN

Ureterorenoscopy (URS) is a minimally invasive treatment option for removal of kidney stones, which has gained importance in this field over the past two decades. This technique has replaced extracorporeal shock wave lithotripsy (ESWL) stone surgery for many indications. It is also particularly important in the diagnostics and treatment for tumors of the upper urinary tract. This article describes the indications, surgical technique and management of complications of URS.


Asunto(s)
Cálculos Renales/patología , Cálculos Renales/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Ureteroscopía/métodos , Neoplasias Urológicas/patología , Neoplasias Urológicas/cirugía , Medicina Basada en la Evidencia , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Resultado del Tratamiento , Ureteroscopía/efectos adversos , Ureteroscopía/instrumentación
9.
Clin Radiol ; 72(1): 95.e9-95.e15, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27737763

RESUMEN

AIM: To compare the diagnostic accuracy of standard screening images plus single-view digital breast tomosynthesis (DBT), using Siemens DBT equipment, with standard screening images plus supplementary mammographic views in non-calcific, screen-detected mammographic abnormalities. MATERIALS AND METHODS: Participants were unselected women aged 50-69 years recalled within a population-based European breast screening programme for assessment of soft-tissue mammographic abnormalities. Supplementary mammographic views (SMVs) and DBT were performed in all cases. A range of equipment was used for screening and supplementary mammography, but all DBT examinations were performed using the Siemens Mammomat Inspiration. A retrospective multi-reader study including 238 cases for whom either histology or at least 2 years' follow-up was available was performed with eight suitably accredited UK breast screening personnel reading all cases under both conditions, with temporal separation. Readers were blinded to case outcomes and findings from other examinations. Diagnostic accuracy using receiver operating characteristic (ROC) analysis was compared between screening plus SMV images and screening plus DBT images. The study was powered to detect a 3% inferiority margin in diagnostic accuracy between methods. RESULTS: The final sample with complete data available for analysis included 195 benign cases (1,560 reads) and 35 malignant cases (280 reads). The DBT method yielded a slightly higher area under the curve (AUC) value than the SMV method (0.870 versus 0.857), but the difference was not statistically significant (p=0.4890), indicating that the methods have equivalent accuracy. CONCLUSION: Siemens DBT demonstrates equivalent diagnostic accuracy according to ROC curve analysis when used in place of SMVs in screen-detected soft-tissue mammographic abnormalities.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Detección Precoz del Cáncer/instrumentación , Imagenología Tridimensional/instrumentación , Mamografía/instrumentación , Tomografía Computarizada por Rayos X/instrumentación , Anciano , Detección Precoz del Cáncer/estadística & datos numéricos , Diseño de Equipo , Análisis de Falla de Equipo , Europa (Continente)/epidemiología , Femenino , Humanos , Imagenología Tridimensional/estadística & datos numéricos , Mamografía/estadística & datos numéricos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Prevalencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Método Simple Ciego , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Pantallas Intensificadoras de Rayos X/estadística & datos numéricos
10.
Urologe A ; 55(11): 1455-1461, 2016 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-27785527

RESUMEN

For selected patients with large-volume prostates, open simple prostatectomy is an effective and durable treatment option. Robot-assisted simple prostatectomy potentially reduces intraoperative blood loss, transfusion rates, length of hospital stay, and complications, but has longer operative times. In all, 16 series with level 3 evidence have been published and demonstrated its safety and efficacy. Long-term data are lacking and comparative outcome studies are needed to establish its benefits compared to open, simple prostatectomy and transurethral laser enucleation techniques.


Asunto(s)
Endoscopía/métodos , Laparoscopía/métodos , Terapia por Láser/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Prostatectomía/métodos , Hiperplasia Prostática/cirugía , Procedimientos Quirúrgicos Robotizados/métodos , Medicina Basada en la Evidencia , Humanos , Masculino , Hiperplasia Prostática/diagnóstico , Resultado del Tratamiento
11.
Urologe A ; 55(10): 1375-1386, 2016 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-27623798

RESUMEN

Percutaneous nephrolithotomy (PCNL) is a well-established minimally invasive treatment option for removal of kidney stones. This technique has now replaced open stone surgery for virtually all indications. This article describes the indications, the surgical technique and the complication management of PCNL.


Asunto(s)
Cálculos Renales/cirugía , Nefrostomía Percutánea/efectos adversos , Nefrostomía Percutánea/métodos , Complicaciones Posoperatorias/etiología , Medicina Basada en la Evidencia , Alemania , Humanos , Cálculos Renales/diagnóstico , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Complicaciones Posoperatorias/prevención & control , Resultado del Tratamiento
12.
Eur Radiol ; 26(2): 342-50, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26017741

RESUMEN

UNLABELLED: Twenty-five-year follow-up data of the Canadian National Breast Cancer Screening Study (CNBSS) indicated no mortality reduction. What conclusions should be drawn? After conducting a systematic literature search and narrative analysis, we wish to recapitulate important details of this study, which may have been neglected: Sixty-eight percent of all included cancers were palpable, a situation that does not allow testing the value of early detection. Randomisation was performed at the sites after palpation, while blinding was not guaranteed. In the first round, this "randomisation" assigned 19/24 late stage cancers to the mammography group and only five to the control group, supporting the suspicion of severe errors in the randomisation process. The responsible physicist rated mammography quality as "far below state of the art of that time". Radiological advisors resigned during the study due to unacceptable image quality, training, and medical quality assurance. Each described problem may strongly influence the results between study and control groups. Twenty-five years of follow-up cannot heal these fundamental problems. This study is inappropriate for evidence-based conclusions. The technology and quality assurance of the diagnostic chain is shown to be contrary to today's screening programmes, and the results of the CNBSS are not applicable to them. KEY POINTS: • The evidence base of the Canadian study (CNBSS) has to be questioned.• Severe flaws in the randomization process and test methods occurred. • Problems were criticized during and after conclusion of the trial by experts.• The results are not applicable to quality-assured screening programs. • The evidence base of this study must be re-analyzed.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Detección Precoz del Cáncer/métodos , Mamografía/métodos , Canadá , Medicina Basada en la Evidencia/normas , Femenino , Estudios de Seguimiento , Humanos , Palpación , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Proyectos de Investigación
13.
Abdom Imaging ; 40(7): 2242-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26054980

RESUMEN

PURPOSE: The purpose of this study was to determine the value of dynamic pelvic floor MRI relative to standard clinical examinations in treatment decisions made by an interdisciplinary team of specialists in a center for pelvic floor dysfunction. METHODS: 60 women were referred for dynamic pelvic floor MRI by an interdisciplinary team of specialists of a pelvic floor center. All patients were clinically examined by an urologist, gynecologist, a proctological, and colorectal surgeon. The specialists assessed individually and in consensus, whether (1) MRI provides important additional information not evident by physical examination and in consensus whether (2) MRI influenced the treatment strategy and/or (3) changed management or the surgical procedure. RESULTS: MRI was rated essential to the treatment decision in 22/50 cases, leading to a treatment change in 13 cases. In 12 cases, an enterocele was diagnosed by MRI but was not detected on physical exam. In 4 cases an enterocele and in 2 cases a rectocele were suspected clinically but not confirmed by MRI. In 4 cases, MRI proved critical in assessment of rectocele size. Vaginal intussusception detected on MRI was likewise missed by gynecologic exam in 1 case. CONCLUSION: MRI allows diagnosis of clinically occult enteroceles, by comprehensively evaluating the interaction between the pelvic floor and viscera. In nearly half of cases, MRI changed management or the surgical approach relative to the clinical evaluation of an interdisciplinary team. Thus, dynamic pelvic floor MRI represents an essential component of the evaluation for pelvic floor disorders.


Asunto(s)
Imagen por Resonancia Magnética , Trastornos del Suelo Pélvico/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana Edad , Diafragma Pélvico/patología , Reproducibilidad de los Resultados
14.
World J Urol ; 33(7): 1039-43, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25164043

RESUMEN

BACKGROUND AND PURPOSE: Residual calculi after stone therapy need to be treated if they are clinically significant, mainly depending on the size of the calculi. There are different ways to detect and measure the size of residual calculi as for example KUB or computed tomography. The Uro Dyna-CT (Siemens Healthcare solutions, Erlangen, Germany) allows cross-sectional imaging and 3D reconstructions during endourological interventions. In this ex vivo study, we investigate the accuracy of imaging residual calculi with the Uro Dyna-CT. MATERIALS AND METHODS: Twenty-seven artificial stones (plaster of Paris) were scanned with the Uro Dyna-CT by a special urolithiasis protocol and post-image processing with 3D-reconstruction and cross-sectional imaging was performed. The major diameter of each stone was measured at the dedicated workstation by one investigator. The same stones were measured randomized with a digital caliper (real size). Finally, the two measurements were compared. The paired t test, Pearson's correlation coefficient, the F Test, a reference area for differences, the intraclass correlation coefficient, the Maloney-Rastogi test and the Bland-Altman analysis were used for statistical analyses. RESULTS: The range of stone sizes was 3-5 mm. We did not find significant differences in the size of the stones measured with the Uro Dyna-CT and the digital caliper (paired t test p = 0.3597) and we showed a good correlation between the two measuring methods (intraclass correlation coefficient 0.4465; p = 0.0088). CONCLUSION: Renal calculi can be measured highly accurately with the Uro Dyna-CT. Whether this technique will lead to less residual fragments after stone treatment needs to be shown in further studies.


Asunto(s)
Imagenología Tridimensional , Tomografía Computarizada por Rayos X , Urolitiasis/diagnóstico , Humanos , Modelos Biológicos , Reproducibilidad de los Resultados
15.
World J Urol ; 32(1): 277-80, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22996760

RESUMEN

BACKGROUND: Imaging of the urinary tract and its surrounding tissue still remains challenging, since standard imaging in the urological operation room consists of fluoroscopy and plain X-rays. The combination of a ceiling-mounted X-ray system and a new urological intervention table now allows cross-sectional imaging and 3D reconstruction to be performed in the endourological operation room (Urological Dyna-CT). MATERIALS AND METHODS: The imaging quality of the Artis Zee Ceiling (Siemens Medical Solutions, Erlangen, Germany) was assessed using slice images of an ex vivo pig kidney model prepared with artificial stones (plaster of Paris). We compared the image quality of three different examination protocols with this model. 3D reconstruction quality was illustrated by means of retrograde filling of one pig`s urinary tract with a diluted contrast medium. RESULTS: Interventional stone detection and localization is possible with a 5 s low-dose Urological Dyna-CT. Detailed imaging of the collecting system by retrograde pyelography is possible with a high image quality. CONCLUSION: The combination of an Artis Zee(®) Ceiling (Siemens Medical Solutions, Erlangen, Germany) with our newly developed urological intervention table we call the Urological Dyna-CT. In addition to such standard procedures as fluoroscopy or plain X-rays, cross-sectional imaging and 3D reconstruction of the urinary tract are possible and provide fast and excellent urological imaging.


Asunto(s)
Endoscopía/métodos , Monitoreo Intraoperatorio/métodos , Tomografía Computarizada por Rayos X/métodos , Sistema Urinario/patología , Urografía , Procedimientos Quirúrgicos Urológicos/métodos , Animales , Endoscopía/instrumentación , Estudios de Factibilidad , Fluoroscopía , Imagenología Tridimensional , Modelos Animales , Monitoreo Intraoperatorio/instrumentación , Quirófanos , Mesas de Operaciones , Porcinos , Tomografía Computarizada por Rayos X/instrumentación , Procedimientos Quirúrgicos Urológicos/instrumentación
16.
World J Urol ; 32(5): 1213-8, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24169818

RESUMEN

PURPOSE: Cross-sectional imaging by computed tomography (CT) is associated with higher radiation dose compared to plain X-ray. The Uro Dyna-CT provides CT-like images in the endourological operating room. Our aim was to reduce the radiation exposure of endourological patients with the Uro Dyna-CT and optimize the cross-sectional image quality. MATERIALS AND METHODS: For the hard contrast protocol, two artificial stones were placed in a Rando-Alderson phantom's left kidney region. Relevant parameters of the standard abdomen protocol were changed. After each modification, two urologists subjectively evaluated the image quality. We developed two customized protocols (standard, low-dose) for hard contrast imaging. To optimize the examination protocol for soft tissue imaging a standardized cone beam phantom was used. Parameters of the preset high-resolution protocol were changed to develop a protocol with similar objective image quality but lower radiation dose. To evaluate the effective radiation dose we embedded 129 thermoluminescence dosimeters in the kidney and ureter region of the Rando-Alderson phantom and performed each protocol five times (stone, soft tissue) and ten times (low-dose protocol). Mean effective dose values per 3D-examination were calculated. RESULTS: We detected a dose area product (DAP) 776.2 (standard) and 163.5 µGym(2) (low-dose) for the stone protocols with an effective dose of 1.96 and 0.33 mSv, respectively. The soft tissue protocol produced a DAP of 5,070 µGym(2) and an effective dose of 7.76 mSv. CONCLUSION: Our newly developed examination protocols for the Uro Dyna-CT provide CT-like image quality during urological interventions with low radiation dose.


Asunto(s)
Protocolos Clínicos , Cálculos Renales/diagnóstico por imagen , Fantasmas de Imagen , Dosis de Radiación , Tomografía Computarizada por Rayos X/métodos , Técnicas de Diagnóstico Urológico/normas
17.
Urologe A ; 52(5): 657-61, 2013 May.
Artículo en Alemán | MEDLINE | ID: mdl-23604448

RESUMEN

The most commonly used treatment modality for urethral strictures is the direct visual internal urethrotomy (DVUI) method according to Sachse. It is an effective short-term treatment, but the long-term success rate is low. A number of factors influence the outcome of DVUI including stricture location, spongiofibrosis and previous endoscopic stricture treatment. Multiple urethrotomy has a negative impact on the success rate of subsequent urethroplasty. A thorough preoperative diagnostic work-up including combined retrograde urethrogram/voiding cystourethrogram (RUG/VCUG) and urethrocystoscopy is, therefore, mandatory to allow for patient counselling regarding the risk of stricture recurrence and other treatment options. After a failed primary DVUI, subsequent urethrotomy cannot be expected to be curative.


Asunto(s)
Endoscopía/métodos , Procedimientos de Cirugía Plástica/métodos , Estrechez Uretral/patología , Estrechez Uretral/cirugía , Procedimientos Quirúrgicos Urológicos Masculinos/métodos , Humanos , Masculino
18.
World J Urol ; 31(5): 1147-51, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22391646

RESUMEN

BACKGROUND AND PURPOSE: Safe and successful puncture of the kidney's collecting system is essential for acute therapy of hydronephrosis or as part of percutaneous nephrolithotomy. The procedure is technically challenging and might lead to major complications. We describe the feasibility of a laser guidance system and three-dimensional puncture planning in the endourological operation room. MATERIALS AND METHODS: An Uro Dyna-CT of the biological model was performed with the Artis Zee(®) Ceiling (Siemens Medical Solutions, Erlangen, Germany) to gain multiplanar reconstructions. 10 punctures were performed with the syngo iGuide(®) laser guidance system. Puncture success was depicted with antegrade contrast filling of the collecting system and fluoroscopic control. Puncture time, tract length, and fluoroscopy time was documented. RESULTS: Data acquisition (8 s) and 3D rendering (48 s) was possible in approximately 1 min. Median time for planning the punctures was 7 [5-15] min. Median puncture time was 4.6 [2-10.2] min. Median tract length was 4.96 [4.33-6.5] cm. Median fluoroscopy time was 0.4 [0.2-1] min. 9 of 10 punctures were successful. A second puncture was needed to gain access to the collecting system in one case, and one puncture was broken up. CONCLUSION: The tested laser guidance system was feasible to perform successful percutaneous punctures of the kidney in this ex vivo study. Handling was intuitive and time within acceptable limits. Due to the requirement of multiplanar reconstructions with higher radiation exposure to the patient than with standard fluoroscopy, this technique should be limited to complex cases.


Asunto(s)
Riñón/cirugía , Rayos Láser , Nefrostomía Percutánea/métodos , Tomografía Computarizada por Rayos X/métodos , Animales , Pollos , Estudios de Factibilidad , Fluoroscopía/métodos , Imagenología Tridimensional/métodos , Modelos Animales , Punciones/métodos , Porcinos
19.
World J Urol ; 31(4): 907-12, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22451168

RESUMEN

OBJECTIVES: To evaluate the influence of different biopsy forcipes on the deflection, irrigant flow, and optical characteristics of flexible ureterorenoscopes and to assess tissue quality for histopathologic evaluation in an ex vivo setting. MATERIALS AND METHODS: The following five different biopsy forcipes were compared: Olympus (FB-56D-1; diameter 5Fr.), R. Wolf (829.601; 3Fr.), Karl Storz Medical (11275ZE; 3Fr.), Boston Scientific (Piranha; 505-160; 3 Fr.), and Cook BIGopsy (115CM; 2.4 Fr.). The devices were tested in 3 different ureterorenoscopes: Storz 11278 VU (Flex-X(2)), Storz 11278 V (Flex-X(C)), and Wolf Cobra (7326071/-6). Tissue samples were obtained from porcine upper urinary tracts. RESULTS: Baseline irrigation flow rates with empty channels were significantly higher in the Wolf Cobra than in Storz ureterorenoscopes (30.5 vs. 23 and 21 ml/min). The BIGopsy forceps allowed for higher flow rates in both Storz ureterorenoscopes (2.2 and 1.3, respectively) when compared to the other devices (0.5 and 0.6 ml/min). The Storz and Wolf biopsy forcipes resulted in the highest impairment of the deflection angle. In all 3 ureterorenoscopes, flow rates and deflection angle were least impaired by the BIGopsy. However, BIGopsy compromised the field of view (20 % reduction vs. 12 % by others). The largest sample of renal pelvis and ureter biopsies was obtained with BIGopsy and Storz(®) forcipes, respectively. The extent of artifacts and denuded urothelium were comparable in all samples. CONCLUSIONS: The various biopsy devices showed different impacts on irrigation flow, deflection, and field of view. The Cook BIGopsy best retains irrigation flow in single-channel flexible ureterorenoscopes and deflection. However, a smaller field of view may complicate handling and tissue acquisition.


Asunto(s)
Biopsia/instrumentación , Ureteroscopios/normas , Sistema Urinario/patología , Animales , Biopsia/métodos , Diseño de Equipo , Modelos Animales , Óptica y Fotónica/normas , Instrumentos Quirúrgicos/normas , Porcinos , Irrigación Terapéutica/normas
20.
World J Urol ; 31(5): 1261-6, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22790391

RESUMEN

BACKGROUND AND PURPOSE: The implementation of the Uro Dyna-CT (Siemens Healthcare Solutions, Erlangen, Germany) with interventional 3D- and cross-sectional imaging necessitates the development of new standards for endourologic procedures such as the customized use of diluted contrast agent. Our aim was to find the ideal contrast agent dilution (CAD) for the interventional use of the Uro Dyna-CT in a standardized setting and prove the experimental findings in a clinical case. MATERIALS AND METHODS: Retrograde pyelographies were performed with 10 different CADs of Imeron 300 (Bracco, Konstanz, Germany) in 10 different pig's urinary tracts. Fluoroscopy, X-ray, 3D- and slice-image reconstruction was performed with the Uro Dyna-CT. Image quality was evaluated, blinded and randomized by 5 observers. Small plastic jars were filled with the CADs and 2 artificial stones (Plaster of paris). Images were evaluated by two observers. The ex vivo findings were transferred to a clinical setting in a complex percutaneous lithotomy procedure. Unweighted and weighted kappa coefficients were calculated to indicate the degree of observers' agreement. RESULTS: Twenty percent diluted contrast agent provides the best image quality and stone detection when interventional cross-sectional imaging is considered without limitations in fluoroscopy or X-ray quality. This was proved in a percutaneous lithotomy of an obese patient. CONCLUSIONS: Image quality of the Uro Dyna-CT can be optimized by the use of 20 % diluted contrast agent. This knowledge helps to provide high-quality 3D imaging in the endourological operation room.


Asunto(s)
Medios de Contraste/normas , Tomografía Computarizada por Rayos X/métodos , Cálculos Urinarios/diagnóstico por imagen , Urografía/métodos , Animales , Fluoroscopía , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Modelos Animales , Nefrostomía Percutánea , Porcinos , Cálculos Urinarios/cirugía
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