Neurogenic bladder sphincter dysfunction (NBSD) is an uncommon disorder frequently induced by lower spinal cord congenital abnormalities such as myelomeningocele (MMC). An antenatal diagnosis of NBSL) can be suspected at ultrasonography (US) when hydronephrosis and bladder wall abnormalities coexist with herniation of the nervous tissue. In early childhood, apart from the lower limb paresis, the clinical expression of spinal cord anomalies can be defined by the Arnold-Chiari malformation and/or syringomyelia, being often characterized as NBSI) [2]. Patients are frequently referred to the specialist for symptoms related to the incontinence and/or to urinary tract infections. In fact, congenital anomalies of the spinal cord more commonly result in a dysfunction of the lower urinary tract, affecting the control mechanism between bladder and urethra, initially sparing the upper urinary system. In these cases the progressive worsening of the upper tract's function results from a secondary damage induced by the bladder dysfunction. As consequence, urinary incontinence was judged in the past the most relevant clinical problem in NBST) and diagnosis and ticatment wete piedominantly focused on the detrus'or muscle activity [19] Conversely, other series of MMC patients showed a higher incidence of upper tract anomalies mainly in the older children [31] In particular, evaluating 404 MMC patients, Wilcock [35] showed an age-related increase of dilatation deformities, other than a high prevalence of primary abnormalities and true anatomical infra-vesical obstruc'' lions; thus, these findings strongly justify the great attention on urological anomalies in patients with spinal cord disorders. In particular, unexpected urodynamic changes and the consequent progressive renal failure may transform these children, also in presence of minor motor dysfunctions, in chronic patients; therefore, the close monitoring of both the bladder status and the renal function is strictly required to choose the most appropriate treatment. On the basis of the previous observations, a complete urological evaluation, including the assessment of morphology and function of the upper and the lower urinary tract, as well as the infection status, represents the first step in a multilevel work-up, in which the nuclear medicine procedures may play an important diagnostic and prognostic role. The most important concept in the imaging of kidneys is the recognition of the intimate relationship between structure and function. Although functional and morphological procedures are generally discussed separately, none of the imaging techniques may be properly evaluated without considering the renal pathophysiology. Moreover, physiological changes in the renal function during the children's growth should be taken in account, inducing the clinician to differentiate between static and dynamic determinants. The parenchymal function and the renal structure are usually evaluated using both hemato-chemical data, such as serum creatinine, and imaging techniques. Standard ultrasonography and nuclear imaging are at present the first-choice investigations in the assessment of the urinary system status. While a clinical role is yet demanded to traditional radiological studies, such as urography and cysto-urethrography, mainly when anatomical information is required, first results obtained by multislice computed tomography (CT), permitting a significant improvement in morphostructural and functional information, strongly suggest its recruitment in the diagnostic scenario [29]. Very important perspectives, already supported by rigorous articles but not yet evidence based by a wide experience, are connected also with the magnetic resonance imaging (MRI), while no sufficient data have been acquired to justify a reliable clinical role for US using contrast media; therefore, waiting for their larger diffusion and a further validation, new diagnostic imaging techniques using CT, MRI, and US can play a role mainly as second-step procedures. Conversely, in these patients standard US is certainly the first diagnostic approach, having completely replaced intravenous pyelography as baseline examination. In the presence of the capability to acquire a satisfactory morphostructural information major advantages, particularly relevant in pediatrics, include mainly the absence of risks connected with contrast media and ionizing radiations; therefore, a safe and effective serial evaluation can be worldwide easily achievable, and diagnosis and monitoring of pathological conditions, such as hydroureteronephrosis, renal scars, and nephrolithiasis, can he reliably achieved. In this scenario, the diffusion of nuclear medicine procedures in the diagnosis and follow-up of urological problems in infants and children has been significantly increased over the past two decades. Many aspects have contributed to this rapid growth, including the introduction of new radiopharmaceuticals and the improvement of imaging devices (gamma cameras) as well as an ever more reliable and reproducible standardization of quantitative functional parameters calculated by computer analysis. Nuclear medicine procedures are non-invasive, requiring neither fasting nor bowel preparation. They can he performed without anesthesia or sedation also in outpatients. Radiopharmaceuticals have no systemic pharmacological effects and do not cause allergic reactions. The radiation-absorbed doses do not reach a harmful range and are much lower compared with those linked with the corresponding radiological techniques. At present, the major advantage of radionuclide studies is consequent to their capability to offer either qualitative and quantitative functional information currently unavailable with other standard imaging modalities. Because many disorders of the urinary tract in children with MMC are part of a dynamic process that requires serial examinations, non-invasive radionuclide studies are a useful tool to dynamically assess the course of these subjects. Few papers have been published to define specifically the usefulness of nuclear medicine in NBSD; therefore, to analyze the possible role of radionuclide procedures in these patients, we discuss in this chapter, with a critical analysis mainly based on our personal experience, four main issues of clinical interest in these disease:(a) urinary tract dilatation; (h) monitoring of the renal function; (c) urinary tract infections; and (d) renal transplant. In nuclear medicine practice, static or dynamic renal scintigraphy and the direct or, less frequently, indirect radionuclide cystography, may be used to reach these different aims.
The role of scintigraphy in the management of children with neurogenic bladder dysfunction
Mansi L.;Cascini G. L.;
2006-01-01
Abstract
Neurogenic bladder sphincter dysfunction (NBSD) is an uncommon disorder frequently induced by lower spinal cord congenital abnormalities such as myelomeningocele (MMC). An antenatal diagnosis of NBSL) can be suspected at ultrasonography (US) when hydronephrosis and bladder wall abnormalities coexist with herniation of the nervous tissue. In early childhood, apart from the lower limb paresis, the clinical expression of spinal cord anomalies can be defined by the Arnold-Chiari malformation and/or syringomyelia, being often characterized as NBSI) [2]. Patients are frequently referred to the specialist for symptoms related to the incontinence and/or to urinary tract infections. In fact, congenital anomalies of the spinal cord more commonly result in a dysfunction of the lower urinary tract, affecting the control mechanism between bladder and urethra, initially sparing the upper urinary system. In these cases the progressive worsening of the upper tract's function results from a secondary damage induced by the bladder dysfunction. As consequence, urinary incontinence was judged in the past the most relevant clinical problem in NBST) and diagnosis and ticatment wete piedominantly focused on the detrus'or muscle activity [19] Conversely, other series of MMC patients showed a higher incidence of upper tract anomalies mainly in the older children [31] In particular, evaluating 404 MMC patients, Wilcock [35] showed an age-related increase of dilatation deformities, other than a high prevalence of primary abnormalities and true anatomical infra-vesical obstruc'' lions; thus, these findings strongly justify the great attention on urological anomalies in patients with spinal cord disorders. In particular, unexpected urodynamic changes and the consequent progressive renal failure may transform these children, also in presence of minor motor dysfunctions, in chronic patients; therefore, the close monitoring of both the bladder status and the renal function is strictly required to choose the most appropriate treatment. On the basis of the previous observations, a complete urological evaluation, including the assessment of morphology and function of the upper and the lower urinary tract, as well as the infection status, represents the first step in a multilevel work-up, in which the nuclear medicine procedures may play an important diagnostic and prognostic role. The most important concept in the imaging of kidneys is the recognition of the intimate relationship between structure and function. Although functional and morphological procedures are generally discussed separately, none of the imaging techniques may be properly evaluated without considering the renal pathophysiology. Moreover, physiological changes in the renal function during the children's growth should be taken in account, inducing the clinician to differentiate between static and dynamic determinants. The parenchymal function and the renal structure are usually evaluated using both hemato-chemical data, such as serum creatinine, and imaging techniques. Standard ultrasonography and nuclear imaging are at present the first-choice investigations in the assessment of the urinary system status. While a clinical role is yet demanded to traditional radiological studies, such as urography and cysto-urethrography, mainly when anatomical information is required, first results obtained by multislice computed tomography (CT), permitting a significant improvement in morphostructural and functional information, strongly suggest its recruitment in the diagnostic scenario [29]. Very important perspectives, already supported by rigorous articles but not yet evidence based by a wide experience, are connected also with the magnetic resonance imaging (MRI), while no sufficient data have been acquired to justify a reliable clinical role for US using contrast media; therefore, waiting for their larger diffusion and a further validation, new diagnostic imaging techniques using CT, MRI, and US can play a role mainly as second-step procedures. Conversely, in these patients standard US is certainly the first diagnostic approach, having completely replaced intravenous pyelography as baseline examination. In the presence of the capability to acquire a satisfactory morphostructural information major advantages, particularly relevant in pediatrics, include mainly the absence of risks connected with contrast media and ionizing radiations; therefore, a safe and effective serial evaluation can be worldwide easily achievable, and diagnosis and monitoring of pathological conditions, such as hydroureteronephrosis, renal scars, and nephrolithiasis, can he reliably achieved. In this scenario, the diffusion of nuclear medicine procedures in the diagnosis and follow-up of urological problems in infants and children has been significantly increased over the past two decades. Many aspects have contributed to this rapid growth, including the introduction of new radiopharmaceuticals and the improvement of imaging devices (gamma cameras) as well as an ever more reliable and reproducible standardization of quantitative functional parameters calculated by computer analysis. Nuclear medicine procedures are non-invasive, requiring neither fasting nor bowel preparation. They can he performed without anesthesia or sedation also in outpatients. Radiopharmaceuticals have no systemic pharmacological effects and do not cause allergic reactions. The radiation-absorbed doses do not reach a harmful range and are much lower compared with those linked with the corresponding radiological techniques. At present, the major advantage of radionuclide studies is consequent to their capability to offer either qualitative and quantitative functional information currently unavailable with other standard imaging modalities. Because many disorders of the urinary tract in children with MMC are part of a dynamic process that requires serial examinations, non-invasive radionuclide studies are a useful tool to dynamically assess the course of these subjects. Few papers have been published to define specifically the usefulness of nuclear medicine in NBSD; therefore, to analyze the possible role of radionuclide procedures in these patients, we discuss in this chapter, with a critical analysis mainly based on our personal experience, four main issues of clinical interest in these disease:(a) urinary tract dilatation; (h) monitoring of the renal function; (c) urinary tract infections; and (d) renal transplant. In nuclear medicine practice, static or dynamic renal scintigraphy and the direct or, less frequently, indirect radionuclide cystography, may be used to reach these different aims.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
