Structure and Function of the Bladder Neck

The studies described here are based on histological serial sections of the entire bladder neck region of 50 male and 15 female deceased of all age groups. For the first time, a musculus vesicoprostaticus et vesicovaginalis, a musculus dilator urethrae and a musculus ejaculatorius are defined. The bipartite musculus sphincter urethrae (glaber et transversostriatus) is the morphological basis for the maintenance of the rest and stress continence. New findings necessitate new interpretations of the basic functions of the lower urinary tract. The results presented here prove that the corresponding morphological substrate differs in many respects from descriptions in the literature.

1 Introduction.- 2 Materials and Methods.- 3 Musculus Detrusor Vesicae.- 3.1 Musculus Detrusor Vesicae.- 3.2 Musculus Pubovesicalis.- 3.3 Musculus Vesicoprostaticus and Musculus Vesicovaginalis.- 3.4 Summary.- 4 The Musculature of the Trigonum Vesicae.- 4.1 Musculus Interuretericus.- 4.2 Musculus Sphincter Vesicae (Vesical or Internal Sphincter).- 4.3 Trigonum Vesicae.- 4.4 Summary.- 5 Diaphragma Urogenitale.- 5.1 Summary.- 6 Musculus Sphincter Urethrae (Urethral or External Sphincter).- 6.1 Summary.- 7 Musculus Dilatator Urethrae.- 7.1 Summary.- 8 Musculus Ejaculatorius.- 8.1 Summary.- 9 Changes of the Muscles of the Lower Urinary Tract with Age.- 9.1 Summary.- 10 Three-Dimensional Model of the Anatomy of the Lower Urinary Tract.- 11 Fundamentals of the Neuroanatomy of the Lower Urinary Tract.- 11.1 Autonomous Innervation of the Lower Urinary Tract.- 11.2 The Voluntary Innervation of the Musculus Sphincter Urethrae.- 11.3 The Sensory Innervation of the Urinary Bladder and the Urethra.- 11.4 Spinal and Supraspinal Influence on the Urinary Reflexes.- 11.5 Summary.- 12 Discussion (Functional Interpretation of the Anatomical Findings).- 12.1 Continence.- 12.2 Micturition.- 12.3 Ejaculation.- 13 Further Studies and New Approaches.- 13.1 Summary.- 14 Terminologia Anatomica of the Lower Urinary Tract.- 15 Summary.- References.