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Influence of Urethral Sphincter Incompetence on Bladder Shape and Function in Myelodysplastic Children
Osamu Yokoyama1, Hideaki Ito1, Mikio Namiki1
1Department of Urology, Faculty of Medical Science, University of Fukui, Fukui, JapanDepartment of Integrative Cancer Therapy and Urology, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan.
Insights
In myelodysplastic children, intermittent catheterization improved bladder function in those with external sphincter incompetence. However, increased urethral resistance negatively impacted bladder shape and function.
Area of Science:
- Pediatric Urology
- Neurology
- Developmental Biology
Background:
- Myelodysplasia can lead to complex bladder and urethral dysfunction.
- Urethral function significantly impacts bladder development and health.
- Understanding these interactions is crucial for effective management.
Purpose of the Study:
- To investigate the relationship between urethral function and bladder shape/function in children with myelodysplasia.
- To assess the effects of intermittent catheterization on bladder outcomes in this population.
Main Methods:
- Study included 39 children with myelodysplasia, with 30 undergoing intermittent catheterization.
- Sphincter incompetence diagnosed via cystography (internal) and urodynamics (external).
- Bladder deformity and compliance were monitored over an average of 8.6 years.
Main Results:
- Intermittent catheterization led to significant improvements in bladder deformity and compliance in 11 patients with external sphincter incompetence.
- Conversely, 8 of 12 patients with an overactive sphincter or high closure pressure showed no improvement or deterioration in bladder deformity.
- Three patients in the latter group experienced upper urinary tract deterioration.
Conclusions:
- Increased urethral resistance is associated with detrimental effects on bladder shape and function.
- Intermittent catheterization is beneficial for myelodysplastic children with external sphincter incompetence.
- Management strategies should consider urethral resistance to prevent bladder deterioration.
Objectives:
This study was undertaken to investigate the influence of the urethral function on bladder shape and function in myelodysplastic children.
Methods:
Of 39 myelodysplastic children, 30 were treated with intermittent catheterization. The diagnosis of internal sphincter incompetence (SI) was based on cystographic findings (open bladder neck) and that of external SI on urodynamic findings (underactive external sphincter identified on electromyography and maximum urethral closure pressure of less than 50 cm H2 O). Follow up included evaluation of bladder deformity and compliance.
Results:
The mean observation period was 8.6 years. In the 11 patients with external SI, bladder deformity and compliance significantly improved as a result of intermittent catheterization. However, of 12 patients with overactive sphincter and/or closure pressure of 50 cm H2 O or more, eight showed deterioration or no improvement in bladder deformity, and three showed upper urinary tract deterioration.
Conclusion:
These results indicate that an increase in urethral resistance may lead to deterioration of bladder shape.
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