Urinary considerations for adult patients with spinal dysraphism

Tethered spinal cord tension assessed via ultrasound elastography in computational and intraoperative human studies

BACKGROUND

Tension in the spinal cord is a trademark of tethered cord syndrome. Unfortunately, existing tests cannot quantify tension across the bulk of the cord, making the diagnostic evaluation of stretch ambiguous. A potential non-destructive metric for spinal cord tension is ultrasound-derived shear wave velocity (SWV). The velocity is sensitive to tissue elasticity and boundary conditions including strain. We use the term Ultrasound Tensography to describe the acoustic evaluation of tension with SWV.

METHODS

Our solution Tethered cord Assessment with Ultrasound Tensography (TAUT) was utilized in three sub-studies: finite element simulations, a cadaveric benchtop validation, and a neurosurgical case series. The simulation computed SWV for given tensile forces. The cadaveric model with induced tension validated the SWV-tension relationship. Lastly, SWV was measured intraoperatively in patients diagnosed with tethered cords who underwent treatment (spinal column shortening). The surgery alleviates tension by decreasing the vertebral column length.

RESULTS

Here we observe a strong linear relationship between tension and squared SWV across the preclinical sub-studies. Higher tension induces faster shear waves in the simulation (R2 = 0.984) and cadaveric (R2 = 0.951) models. The SWV decreases in all neurosurgical procedures (p < 0.001). Moreover, TAUT has a c-statistic of 0.962 (0.92-1.00), detecting all tethered cords.

CONCLUSIONS

This study presents a physical, clinical metric of spinal cord tension. Strong agreement among computational, cadaveric, and clinical studies demonstrates the utility of ultrasound-induced SWV for quantitative intraoperative feedback. This technology is positioned to enhance tethered cord diagnosis, treatment, and postoperative monitoring as it differentiates stretched from healthy cords.

Sacral Spina Bifida Occulta: A Frequency Analysis of Secular Change

Substantial relaxation of natural selection beginning around 1900 changed the mutation/selec­tion balance of modern genetic material, producing an increase in variable anatomical structures. While multiple structures have been affected, the temporal increase in variations of the sacrum, specifically, ‘Sa­cral Spina Bifida Occulta,’ have been reliably demonstrated on a localised scale. Calculation of largescale frequency has been hindered by the localised nature of these publications, the morphological variability of this variation, and potential pathological associations, which have produced divergent classifications, and conflicting reported rates of occurrence. A systematic review of the reported literature was conducted to provide an objective analysis of Sacral Spina Bifida Occulta frequency from 2500 BCE to the present. This review was designed to compensate for observed inconsistencies in reporting and to ascertain, for the first time, the temporal trajectory of this secular trend. A systematic review of Sacral Spina Bifida Occulta lit­erature was conducted through the strict use of clinical meta-analysis criteria. Publications were retrieved from four databases: PubMed, Embase, the Adelaide University Library database, and Google Scholar. Data were separated into three historical groups, (1 = <1900, 2 = 1900 to 1980 and 3 = >1980), and frequency outcomes compared, to determine temporal rates of occurrence. A total of 39/409 publications were included in the final analysis, representing data for 16,167 sacra, spanning a period of 4,500 years. Statistically significant results were obtained, with total open S1 frequen­cy increasing from 2.34%, (79 to 1900CE), to 4.80%, (1900 to 1980CE) and to 5.43% (>1980CE). These increases were significant at p<0.0001, with Chi-squared analysis. A clear secular increase in the global frequency of Sacral Spina Bifida Occulta has been demonstrated from 1900 to the present. This research provides a novel and adaptable framework for the future assessment of variation distribution, with impor­tant implications for the fields of biological anthropology and bioarchaeology.

Perspectives on urological care in spina bifida patients

Spina bifida (SB) is a neurogenetic disorder with a complex etiology that involves genetic and environmental factors. SB can occur in two major forms of open SB or SB aperta and closed SB or SB occulta. Myelomeningocele (MMC), the most common neural tube defects (NTDs), occurs in approximately 1 in 1,000 births. Considering non-genetic factors, diminished folate status is the best-known factor influencing NTD risk. The methylenetetrahydrofolate reductase (MTHFR) gene has been implicated as a risk factor for NTDs. The primary disorder in the pathogenesis of MMC is failed neural tube closure in the embryonic spinal region. The clinical manifestation of SB depends on clinical type and severity. SB can be detected in the second trimester using ultrasound which will reveal specific cranial signs. The management of MMC traditionally involves surgery within 48 h of birth. Prenatal repair of MMC is recommended for fetuses who meet maternal and fetal Management of Myelomeningocele Study (MOMS) specified criteria. Urological manifestations of SB include urinary incontinence, urolithiasis, sexual dysfunction, renal dysfunction, and urinary tract infection. Renal failure is among the most severe complications of SB. The most important role of the urologist is the management of neurogenic bladder. Medical management with clean intermittent catheterization and anticholinergic treatment is generally considered the gold standard of therapy. However, when this therapy fails surgical reconstruction become the only remaining option. This review will summarize the pathogenesis, risk factors, genetic contribution, diagnostic test, and management of SB. Lastly, the urologic outcomes and therapies are reviewed.

Refractory Urinary Incontinence in Girls: The Role of the Bladder Neck

BACKGROUND

Prevalence of lower urinary tract dysfunction (LUTD) in children is between 6 and 9% with urinary incontinence (UI) being one of the most common symptom.

VARIOUS ASPECTS OF LOWER URINARY TRACT SYMPTOMS LUTS

Anatomical anomalies of the urinary tract as well as neurogenic underlying pathology can results in LUTS. Comorbidities and long-term consequences of the LUTD for the female patients as well as genetic issues are also briefly discussed.

THE ROLE OF THE BLADDER NECK

Thanks to urodynamics, we have learnt a lot about the lower urinary tract function, but the role of the bladder neck in the pathophysiology of LUTS in children is not clear. Secondary bladder neck hypertrophy is a well-described pathology, but there is no standardized treatment for this phenomenon. Primary bladder neck dysfunction has already been defined by the International Children's Continence Society.

REFRACTORY UI IN GIRLS

Uniform diagnostic protocols are used in these girls with UI. Treatment consists of standard urotherapy, additional interventions, and pharmacotherapy in selected cases. Those with refractory UI require careful reassessment to look for the unrecognized disorders. Invasive urodynamics should be done in those patients. Ultrasound of the bladder neck region and the pelvic floor can be helpful, but its interpretation is very subjective. In a small group bladder neck insufficiency can be found and those might benefit from a surgical intervention.

FUTURE PERSPECTIVE

Strict criteria of the bladder neck insufficiency in children must be defined. Early surgical intervention in girls with bladder neck insufficiency might reduce the long period of intensive conservative treatment.

Outcomes of intra-detrusor injections of botulinum toxin in patients with spina bifida: A systematic review

CONTEXT

Bladder management in spina bifida patients relies on clean intermittent catheterization and oral antimuscarinics with a significant failure rate. The efficacy of intradetrusor injections of botulinum toxin has been confirmed in patients with spinal cord injury or multiple sclerosis but not in patients with myelomeningocele.

OBJECTIVE

To conduct a systematic review of current evidence regarding the efficacy of intra-detrusor injections of Botulinum Toxin A (BTX-A) in spina bifida patients with neurogenic detrusor overactivity (NDO) refractory to antimuscarinics.

METHODS

A research has been conducted on Medline and Embase using the keywords: ("spina bifida" OR "myelomeningocele" OR "dysraphism") AND "toxin." The search strategy and studies selection were performed using the PICOS method according to the PRISMA statement.

RESULT

Twelve published series were included (n = 293 patients). All patients were <18 years old. There was no randomized study comparing BTX-A versus placebo and most studies had no control group. Most studies reported a clinical and urodynamic improvement with resolution of incontinence in 32-100% of patients, a decrease in maximum detrusor pressure from 32 to 54%, an increase of maximum cystometric capacity from 27 to 162%, and an improvement in bladder compliance of 28-176%. Two studies suggested lower efficacy in patients with low compliance bladder compared to those with isolated detrusor overactivity.

CONCLUSION

Intradetrusor injections of BTX-A could be effective in children with spina bifida but this assumption is not supported by high level of evidence studies. There is no data available in adult patients. Neurourol. Urodynam. 36:557-564, 2017. © 2016 Wiley Periodicals, Inc.

Congenital causes of neurogenic bladder and the transition to adult care

The population of patients with congenital genitourinary disorders has unique healthcare demands that require an additional interpersonal and medical skillset. Adults with congenital neurogenic bladder may have complex urinary anatomy, abnormal bladder function and atypical voiding mechanisms. While initial surgery and care of these patients is typically managed by a pediatric urologist, growth and development into adulthood necessitates transition of care to an adult care team. Failure of transition to adult care has been demonstrated to result in lower quality healthcare and increased risk of developing preventable complications.

Lower urinary tract dysfunction in the neurological patient: clinical assessment and management

Lower urinary tract (LUT) dysfunction is a common sequela of neurological disease, resulting in symptoms that have a pronounced effect on quality of life. The site and nature of the neurological lesion affect the pattern of dysfunction. The risk of developing upper urinary tract damage and renal failure is much lower in patients with slowly progressive non-traumatic neurological disorders than in those with spinal cord injury or spina bifida; this difference in morbidity is taken into account in the development of appropriate management algorithms. Clinical assessment might include tests such as uroflowmetry, post-void residual volume measurement, renal ultrasound, (video-)urodynamics, neurophysiology, and urethrocystoscopy, depending on the indication. Incomplete bladder emptying is most often managed by intermittent catheterisation, and storage dysfunction by antimuscarinic drugs. Intradetrusor injections of onabotulinumtoxinA have transformed the management of neurogenic detrusor overactivity. Neuromodulation offers promise for managing both storage and voiding dysfunction. An individualised, patient-tailored approach is required for the management of LUT dysfunction associated with neurological disorders.