Sunday, April 27, 2008

Treatment of the neurogenic bladder in spina bifida.

de Jong TP, Chrzan R, Klijn AJ, Dik P. Treatment of the neurogenic bladder in spina bifida. Pediatric Nephrology. 2008 Mar 19;

Pediatric Renal Center, Department of Pediatric Urology, University Children’s Hospital, UMCU, P.O. Box 85090, 3508 AB, Utrecht, The Netherlands.

Renal damage and renal failure are among the most severe complications of spina bifida. Over the past decades, a comprehensive treatment strategy has been applied that results in minimal renal scaring. In addition, the majority of patients can be dry for urine by the time they go to primary school. To obtain such results, it is mandatory to treat detrusor overactivity from birth onward, as upper urinary tract changes predominantly start in the first months of life. This means that new patients with spina bifida should be treated from birth by clean intermittent catheterization and pharmacological suppression of detrusor overactivity. Urinary tract infections, when present, need aggressive treatment, and in many patients, permanent prophylaxis is indicated. Later in life, therapy can be tailored to urodynamic findings. Children with paralyzed pelvic floor and hence urinary incontinence are routinely offered surgery around the age of 5 years to become dry. Rectus abdominis sling suspension of the bladder neck is the first-choice procedure, with good to excellent results in both male and female patients. In children with detrusor hyperactivity, detrusorectomy can be performed as an alternative for ileocystoplasty provided there is adequate bladder capacity. Wheelchair-bound patients can manage their bladder more easily with a continent catheterizable stoma on top of the bladder. This stoma provides them extra privacy and diminishes parental burden. Bowel management is done by retrograde or antegrade enema therapy. Concerning sexuality, special attention is needed to address expectations of adolescent patients. Sensibility of the glans penis can be restored by surgery in the majority of patients.

PMID: 18350321
Williams H. The venous hypothesis of hydrocephalus. Medical Hypotheses. 2008;70(4):743-7. Epub 2007 Oct 4.

19 Elibank Road, Eltham, London SE9 1QQ, United Kingdom.

Pressure in the central nervous system (CNS) depends upon the volume of tissue that it contains. This includes blood, cerebrospinal fluid (CSF), nerves and any space occupying lesions. The dependency of pressure on volume arises because the CNS is confined by bone. Venous and CSF pressure is linked to overall pressure. Arterial pressure can increase in response to overall pressure to maintain arterial supply. Continuous arterial supply can be maintained because venous blood flows out of the CNS. Reduced volumes of arterial blood will enter the system if venous outflow is interrupted. Increase in CNS volume, as occurs with space occupying lesions, causes compression of veins. This may result in increased venous pressure and reduction in flow of blood out of the CNS. Cerebrospinal fluid (CSF) is extracellular fluid; its absorption back into the circulation is influenced by venous pressure. Any increased in CNS tissue volumes can therefore lead to CSF accumulation. This may then exacerbate the hydrocephalus by further increasing overall CNS volume. Free flow of CSF around the CNS facilitates venous drainage. Blockages to CSF flow can act like space occupying lesions. Chiari malformations, where the cerebellar tonsils obstruct the foramen magnum lead to reductions in CSF flow that can occur intermittently. This leads to impairment of venous drainage which may result in accumulation of CSF. The head or the spine can be affected together or separately. The manifestation of excess fluid accumulation is hydrocephalus and syringomyelia. The speed and origin of venous insufficiency influences the morphology of individual cases particularly with regard to lateral ventricle size. When pressure increases rapidly there may be little time for CSF accumulation. Oedema, compression of intracranial CSF spaces and cerebral ischaemia follows. When venous pressure is only slightly elevated CSF will accumulate and the manifestations of ischaemia may be less apparent, although ischaemia will be a feature of all instances of pathologically raised CNS pressure.

PMID: 17919832

A unifying hypothesis of hydrocephalus, Chiari malformation, syringomyelia, anencephaly and spina bifida

Williams H. A unifying hypothesis of hydrocephalus, Chiari malformation, syringomyelia, anencephaly and spina bifida. Cerebrospinal Fluid Research. 2008 Apr 11;5(1):7

ABSTRACT: This review is a modified version of the Casey Holter Memorial prize essay presented to the Society for Research into Hydrocephalus and Spina Bifida, June 29th 2007, Heidelberg, Germany. It describes the origin and consequences of the Chiari malformation, and proposes that hydrocephalus is caused by inadequate central nervous system (CNS) venous drainage. A new hypothesis regarding the pathogenesis, anencephaly and spina bifida is described. Any volume increase in the central nervous system can increase venous pressure. This occurs because veins are compressible and a CNS volume increase may result in reduced venous blood flow. This has the potential to cause progressive increase in cerebrospinal fluid (CSF) volume. Venous insufficiency may be caused by any disease that reduces space for venous volume. The flow of CSF has a beneficial effect on venous drainage. In health it moderates central nervous system pressure by moving between the head and spine. Conversely, obstruction to CSF flow causes localised pressure increases, which have an adverse effect on venous drainage. The Chiari malformation is associated with hindbrain herniation, which may be caused by low spinal pressure relative to cranial pressure. In these instances, there are hindbrain-related symptoms caused by cerebellar and brainstem compression. When spinal injury occurs as a result of a Chiari malformation, the primary pathology is posterior fossa hypoplasia, resulting in raised spinal pressure. The small posterior fossa prevents the flow of CSF from the spine to the head, as blood enters the central nervous system during movement. Consequently, intermittent increases in spinal pressure caused by movement, result in injury to the spinal cord. It is proposed that posterior fossa hypoplasia, which has origins in fetal life causes syringomyelia after birth and leads to damage to the spinal cord in spina bifida. It is proposed that hydrocephalus may occur as a result of posterior fossa hypoplasia, where raised pressure occurs as a result of obstruction to flow of CSF from the head to the spine, and cerebral injury with raised pressure occurs in anencephaly by this mechanism. The current view of dysraphism is that low central nervous system pressure and exposure to amniotic fluid, damage the central nervous system. The hypothesis proposed in this essay supports the view that spina bifida is a manifestation of progressive hydrocephalus in the fetus. It is proposed that mesodermal growth insufficiency influences both neural tube closure and central nervous system pressure, leading to dysraphism.

PMID: 18405364

Antegrade continence enema (ACE): current practice.

Sinha CK, Grewal A, Ward HC. Antegrade continence enema (ACE): current practice. Pediatric Surgery International. 2008 Apr 12;

The purpose of this study was to assess current status of antegrade continence enema (ACE) procedure taking into account the recent improvement in the technique and outcome. Reviewing our record of 48 patients with ACE procedure performed between January 2002 and May 2007, we found that the underlying diagnoses were idiopathic constipation in 56%, anorectal malformation in 31%, spina bifida in 8% and Hirschsprung's disease in 4%. Mean age of operation was 10.7 years. Appendix was used as stoma in 73% of cases. Stomal stenosis requiring revision was seen in 6% of cases and continence was achieved in 92% of cases. A systematic search of database was performed for the same period. Twenty-four studies describing 676 patients were found. The mean age was 10 years and various sites used for ACE were, right side of abdomen in 71%, umbilicus in 15% and left side of abdomen in 14%. The incidence of open and laparoscopic procedures were 87 and 13%, respectively. Appendix was used for stoma in 76% procedures. Other operative modalities were retubularised colon, retubularised ileum, caecal button and caecostomy tube, etc. The mean volume of enema fluid used was 516 ml. The mean evacuation time was 42 min. Stomal stenosis requiring revision was seen in 13% of cases. Continence was achieved in 93% of cases. There has been significant improvement in the outcome during last 5 years in comparison to the outcome published in late 1990s. Advancements in techniques, better-trained stoma care nurses and better stoma appliances could have played major role in this success.

PMID: 18408942

Fetal spina bifida repair--current trends and prospects of intrauterine neurosurgery

Fichter MA, Dornseifer U, Henke J, Schneider KT, Kovacs L, Biemer E, Bruner J, Adzick NS, Harrison MR, Papadopulos NA. Fetal spina bifida repair--current trends and prospects of intrauterine neurosurgery. Fetal Diagnosis Therapy. 2008;23(4):271-86.

Department of Plastic and Reconstructive Surgery, Technical University of Munich, Munich, Germany.

Myelomeningocele is a common dysraphic defect leading to severe impairment throughout the patient's lifetime. Although surgical closure of this anomaly is usually performed in the early postnatal period, an estimated 330 cases of intrauterine repair have been performed in a few specialized centers worldwide. It was hoped prenatal intervention would improve the prognosis of affected patients, and preliminary findings suggest a reduced incidence of shunt-dependent hydrocephalus, as well as an improvement in hindbrain herniation. However, the expectations for improved neurological outcome have not been fulfilled and not all patients benefit from fetal surgery in the same way. Therefore, a multicenter randomized controlled trial was initiated in the USA to compare intrauterine with conventional postnatal care, in order to establish the procedure-related benefits and risks. The primary study endpoints include the need for shunt at 1 year of age, and fetal and infant mortality. No data from the trial will be published before the final analysis has been completed in 2008, and until then, the number of centers offering intrauterine MMC repair in the USA is limited to 3 in order to prevent the uncontrolled proliferation of new centers offering this procedure. In future, refined, risk-reduced surgical techniques and new treatment options for preterm labor and preterm rupture of the membranes are likely to reduce associated maternal and fetal risks and improve outcome, but further research will be needed.

PMID: 18417993

Prospective, longitudinal evaluation of health related quality of life in the pediatric spina bifida population undergoing reconstructive urological s

Parekh AD, Trusler LA, Pietsch JB, Byrne DW, DeMarco RT, Pope JC 4th, Adams MC, Deshpande JK, Brock JW 3rd. Prospective, longitudinal evaluation of health related quality of life in the pediatric spina bifida population undergoing reconstructive urological surgery. Journal of Urology. 2006 Oct;176(4 Pt 2):1878-82.

General Clinical Research Center, Vanderbilt Children's Hospital, 2200 Children's Way, Nashville, TN 37232, USA.

PURPOSE: Spina bifida, the most frequent permanently debilitating birth defect, results in major urological problems of voluntary bladder control and bowel function, which may impair quality of life. We prospectively assessed quality of life in patients with spina bifida using child and parent reports simultaneously. This study had 3 goals, that is to 1) document baseline health related quality of life in patients with spina bifida preoperatively, 2) study health related quality of life, reporting differences between parents and children, and 3) study changes in health related quality of life prospectively at preoperative and postoperative intervals.

MATERIALS AND METHODS: Patients with spina bifida who were 2 to 18 years old and required reconstructive urological surgery in 2004 were included in the study. Demographic survey and the validated PedsQL 4.0 health related quality of life questionnaire were used preoperatively and postoperatively. A clinical outcomes data set was completed after the clinician saw the patient. PedsQL 4.0 subscales were scored using the algorithms provided.

RESULTS: The response rate was 100%. Mean participant age was 10.3 years. Preoperatively child physical and psychosocial health and school functioning were significantly higher than parent reports (p <0.001). Overall health related quality of life in patients with spina bifida was lower than in healthy children (62.4 vs 85, p <0.001). Six weeks postoperatively significant differences in health related quality of life reporting between parents and children had lowered. Six months postoperatively child emotional and social functioning scores were higher than parent scores (p <0.001). No correlation was found between health related quality of life, and clinical and demographic factors due to insufficient sample size.

CONCLUSIONS: Children with spina bifida recorded higher health related quality of life scores than parents/guardians. This health related quality of life study addresses concerns that impact daily quality of life in patients with spina bifida. Future health related quality of life studies in patients with spina bifida should use child self-reports.

PMID: 16945679

Current approaches to the urologic care of children with spina bifida

Joseph DB. Current approaches to the urologic care of children with spina bifida. Current Urology Reports. 2008 Mar;9(2):151-7.

Most children born with spina bifida, the most common disabling congenital abnormality, have normal renal function. If left untreated, more than half of these children will have serious renal deterioration by age 5. This deterioration is secondary to hostile neurogenic changes of the bladder. Renal development should follow a normal course when close evaluation and intervention are undertaken during the newborn period and toddler years. As children age, attention is directed to quality-of-life issues, such as the establishment of urinary and bowel continence. Teenagers face the responsibility of understanding their medical condition and should begin to assume responsibility for their own care with eventual transition to the adult health care system. This article describes the foundations of management, beginning at birth, for caring for children with spina bifida.

PMID: 18420000

Estimation of Renal Function in Children and Adolescents With Spinal Dysraphism.

Abrahamsson K, Jodal U, Sixt R, Olsson I, Sillén U. Estimation of Renal Function in Children and Adolescents With Spinal Dysraphism. Journal Urology. 2008 Apr 22;179(6):2407-2409

PURPOSE: In children with spinal dysraphism such as myelomeningocele the relation between muscle mass and body composition varies considerably. Therefore, it is difficult to evaluate the relevance of renal function assessments done with serum creatinine. Since serum cystatin C has been suggested to be independent of body size and composition, this evaluation was compared to chromium(51) edetic acid clearance.

MATERIALS AND METHODS: Simultaneous measurements of cystatin C and chromium(51) edetic acid clearance were performed prospectively in 65 patients 2 to 19 years old with spinal dysraphism.

RESULTS: Cystatin C values were within the normal range in all patients, while chromium(51) edetic acid clearance was reduced in 10. A significant relation was seen.

CONCLUSIONS: Using chromium(51) edetic acid clearance as a gold standard, children with spinal dysraphism and slightly to moderately reduced renal function may remain undiagnosed if cystatin C is used for evaluation.

PMID: 18433781