RESUMEN
PURPOSE: To evaluate both morphology of the urethra and its supporting structures using endovaginal magnetic resonance imaging (EV-MRI) and the grade of the bladder neck prolapsus using dynamic pelvic MRI (DP-MRI) in women with stress urinary incontinence (SUI). MATERIALS AND METHODS: We compared 25 women with SUI and 8 controls according to the different layers of the urethra, the degree of distortion in the periurethral, paraurethral, and pubourethral ligaments, the vesicourethral angle, the retropubic space, and the thickness of the puborectal muscle. The SUI group was also evaluated according to the number of deliveries and degree of the bladder neck prolapsus. RESULTS: Significant differences were found in the thickness of each three layers of the urethra between the two groups (P < .05). There was a significantly higher pubourethral ligament distortion (P = .024) and larger vesicourethral angle (P = .000) in women with SUI. In women with SUI, there was no significant relationship between the number of deliveries and the degree of the bladder neck prolapsus (P > .05). CONCLUSION: The combined usage of the EV-MRI and DP-MRI can provide complementary information concerning certain structural abnormalities with specific dysfunction, such as vesicourethral angle increase and pubourethral ligament distortion in patients with SUI.
Asunto(s)
Imagen por Resonancia Magnética/métodos , Uretra/patología , Incontinencia Urinaria de Esfuerzo/patología , Adulto , Anciano , Distribución de Chi-Cuadrado , Cistocele/patología , Femenino , Humanos , Ligamentos/patología , Imagen por Resonancia Magnética/instrumentación , Persona de Mediana Edad , Músculo Esquelético/patología , Músculo Liso/patologíaRESUMEN
Distraction osteogenesis is a well established clinical treatment for limb length discrepancy and skeletal deformities. Transforming growth factor beta 1 (TGF-beta1) is a multifunctional peptide which controls proliferation and expression of cells specific to bone like chondrocytes, osteoblasts, osteoclasts including mesenchymal precursor cells. To decrease the external fixation time with increasing the strength of regenerate (newly formed bone after distraction) we tested the effect of locally applied transforming growth factor beta 1 on distraction osteogenesis. A total of 28 mature female white New zealand rabbits weighing 3,5 kg-4,5 kg were studied. 10 animals were belonging to biomechanical testing group (5 for the study and 5 for the control subgroups), and the others were to histology group. In biomechanical group after tibial osteotomy TGF-beta1 was applied subperiosteally for 5 days just proximal to osteotomy site. Control group received only the solvent. Seven days after tibial osteotomy distraction was started at a rate of 0.25 mm/12 hours for 3 weeks with a unilateral fixator. Rabbits were sacrificed at the end of a consolidation period 8 week after tibial osteotomy. We assessed density of the elongation zone of rabbit tibial bones with the computed tomography. Then biomechanical parametres were assessed using the torsional testing using the material testing machine. In histology group rabbits were classified as control and study (rabbits that were given TGF-beta1). Rabbits were sacrificed at the end of first week, second week and fourth week also at the end of consolidation period 8 week after tibial osteotomy. Immunohistochemical and histologic parameters were examined. Biomechanical testing was applied as torsional testing. These values are used in determination of maximal loading, stiffness and energy absorbed during testing (brittleness). The histomorphometric examination looked for the differences between the study and control groups in terms of bone formation pattern, bone quality and quantity. The immunohistochemical studies investigated the mechanism of TGF-beta1, and its presence in different cell types. The results of this study suggest that locally applied TGF-beta1 improves the mineral density of distraction gap and load to failure(energy absorbed during testing). Though there is no significant histomorphometric difference between the study and control groups, there is an increased bone mineral density and an according maximum energy absorbance in the study group. This effect can be explained by the following mechanism: TGF-beta1 exerts its effect on two different receptor types (Type 1 and 2). Type 1 receptors are localized to bone matrix and type 2 receptors are localized to the intracellular space. The specific stains utilized in the current experiment are specific to type 2 receptors. They have been shown to be down-regulated by exogenous TGF-beta1 injections. Most probably, type 1 receptors are up-regulated by this exogenous administration, but unfortunately, there is currently no specific stain on tha market to display type 1 receptors and to prove this explanation.