The purpose of this study was to identify the microscopic arterial vascularization of the corpora cavernosa (CC) of the penis using computer‐assisted anatomic dissection (CAAD), determine the ...contribution of the different penile arteries towards this vascularization, detail the nature of cavernospongiosum shunts, and locate the anastomoses between these different arteries. Tissue specimens were taken from five donors who donated their bodies to science. The specimens were fixed in 10% formalin and sliced into a series of five 5‐μm sections at intervals of 200 μm. The first section was stained with hematoxylin‐eosin or Masson's trichrome and the second with anti‐protein S100. The cavernous artery of the penis is not the only source of arterial vascularization of the CC. In four of the five cases studied, we found two to four perforating branches arising from the dorsal arteries of the penis that join up with the cavernous artery of the penis or that are solely responsible for the vascularization of the distal third of the penis. The bulbo‐urethral and urethral arteries are situated outside of the tunica albuginea of the corpus spongiosum on their lateral and dorsal sides. The anastomoses do not occur between the cavernous artery of the penis and the corpus spongiosum but between the cavernous artery of the penis and the urethral artery on the surface of the tunica albuginea. All of these arteries are accompanied by nerve branches. The CC were found to be vascularized by both cavernous and dorsal arteries of the penis. Intrapenile vascularization is organized around four arterial axes, which are anastomosed by multiple neurovascular shunts.
Background
Erectile dysfunction, principally related to injury of the autonomic nerve fibers in men, is a major cause of postoperative morbidity after anterolateral dissection during total mesorectal ...excision (TME) for rectal adenocarcinoma. However, the autonomic innervation of erectile bodies is less known in women, and the anterolateral plane of dissection during TME remains unclear. The existence of the rectovaginal septum (RVS) is controversial. The purpose of the present study was to identify the RVS in the human fetus and adult female by dissection, immunohistochemistry, and three-dimensional reconstruction, and to define its relationship with erectile nerve fibers so as to determine the anterolateral plane of dissection during TME, which could reduce postoperative sexual dysfunction in women.
Method
Macroscopic dissection, histologic studies, and immunohistochemistry examination with 3D reconstruction were performed in six fresh female adult cadavers and six female fetuses.
Results
The RVS was clearly definable in all adult specimens. It was composed of multiple connective tissue, with smooth muscle fibers originating from the uterus and the vagina. It is closely applied to the vagina and has a relationship with the neurovascular bundles (NVBs) that contain erectile fibers intended for the clitoris. The NVBs are situated anteriorly to the posterior extension of rectovaginal septum. This posterior extension protects the NVBs during the anterior and anterolateral dissection for removal of rectal cancer.
Conclusions
To reduce the risk of postoperative sexual dysfunction in women undergoing TME for rectal cancer, we recommend careful dissection to the anterior mesorectum to develop a plane of dissection behind the posterior extension of the RVS if oncologically reasonable.
Sphincter continence and sexual function require co‐ordinated activity of autonomic and somatic neural pathways, which communicate at several levels in the human pelvis. However, classical dissection ...approaches are only of limited value for the determination and examination of thin nerve fibres belonging to autonomic supralevator and somatic infralevator pathways. In this study, we aimed to identify the location and nature of communications between these two pathways by combining specific neuronal immunohistochemical staining and three‐dimensional reconstruction imaging. We studied 14 normal human fetal pelvic specimens (seven male and seven female, 15–31 weeks’ gestation) by three‐dimensional computer‐assisted anatomic dissection (CAAD) with neural, nitrergic and myelin sheath markers. We determined the precise location and distribution of both the supra‐ and infralevator neural pathways, for which we provide a three‐dimensional presentation. We found that the two pathways crossed each other distally in an X‐shaped area in two spatial planes. They yielded dual innervation to five targets: the anal sphincter, levator ani muscles, urethral sphincter, corpus spongiosum and perineal muscles, and corpora cavernosa. The two pathways communicated at three levels: proximal supralevator, intermediary intralevator and distal infralevator. The dorsal penis/clitoris nerve (DN) had segmental nitrergic activity. The proximal DN was nNOS‐negative, whereas the distal DN was nNOS‐positive. Distal communication was found to involve interaction of the autonomic nitrergic cavernous nerves with somatic nitrergic branches of the DN, with nitrergic activity carried in the distal part of the nerve. In conclusion, the pelvic structures responsible for sphincter continence and sexual function receive dual innervation from the autonomic supralevator and the somatic infralevator pathways. These two pathways displayed proximal, intermediate and distal communication. The distal communication between the CN and branches of the DN extended nitrergic activity to the distal part of the cavernous bodies in fetuses of both sexes. These structures are important for erectile function, and care should therefore be taken to conserve this communication during reconstructive surgery.
Innervation of the penis supports erectile and sensory functions.
This article aims to study the efferent autonomic (visceromotor) and afferent somatic (sensory) nervous systems of the penis and to ...investigate how these systems relate to vascular pathways.
Penises obtained from five adult cadavers were studied via computer-assisted anatomic dissection (CAAD).
The number of autonomic and somatic nerve fibers was compared using the Kruskal–Wallis test.
Proximally, penile innervation was mainly somatic in the extra-albugineal sector and mainly autonomic in the intracavernosal sector. Distally, both sectors were almost exclusively supplied by somatic nerve fibers, except the intrapenile vascular anastomoses that accompanied both somatic and autonomic (nitrergic) fibers. From this point, the neural immunolabeling within perivascular nerve fibers was mixed (somatic labeling and autonomic labeling). Accessory afferent, extra-albugineal pathways supplied the outer layers of the penis.
There is a major change in the functional type of innervation between the proximal and distal parts of the intracavernosal sector of the penis. In addition to the pelvis and the hilum of the penis, the intrapenile neurovascular routes are the third level where the efferent autonomic (visceromotor) and the afferent somatic (sensory) penile nerve fibers are close. Intrapenile neurovascular pathways define a proximal penile segment, which guarantees erectile rigidity, and a sensory distal segment. Diallo D, Zaitouna M, Alsaid B, Quillard J, Ba N, Allodji RS, Benoit G, Bedretdinova D, and Bessede T. The visceromotor and somatic afferent nerves of the penis. J Sex Med 2015;12:1120–1127.
Purpose
The aim was to eliminate, by DNA comparison, any identity mismatch between operative and biopsy specimens and to analyse the determinants of all pT0 prostate cancers occurred in a single ...institution.
Methods
All prostate pT0 cases in a single institution over 20 years were investigated. None of the patients had been diagnosed after a transurethral resection of the prostate nor had they received neoadjuvant hormonal treatment. The biopsies performed in other centres had been referred for a centralized pathologic re-analysis. DNA analysis was performed in samples from operative and biopsy specimens, and pairs of tissues were blindly constituted. Correct matching was verified in each pair and compared to the original database in order to comment on the occurrence of identity mismatches in the series.
Results
Nineteen patients (0.77 %) had been diagnosed as having pT0 prostate cancer among the 2,462 RP procedures performed over 19 years. The biopsy re-analysis invalidated the initial diagnosis of prostate cancer in one biopsy set performed elsewhere. Among 12 entirely processed cases, the biochemistry procedure evaluated as “very unlikely” the occurrence of an error in tissue identification in the biopsy setting, during the surgical procedure or the pathological analysis. No identification error of tissue samples was established in this first verified pT0 series.
Conclusions
Although it must be suspected, specimen identification error was not a cause for pT0 prostate cancer. Only after a full pathological and DNA verification, the pT0 stage remains a sole entity, unexplained in most cases.
Classic anatomical methods have failed to determine the precise location, origin and nature of nerve fibres in the inferior hypogastric plexus (IHP). The purpose of this study was to identify the ...location and nature (adrenergic and/or cholinergic) of IHP nerve fibres and to provide a three‐dimensional (3D) representation of pelvic nerves and their relationship to other anatomical structures. Serial transverse sections of the pelvic portion of two human male fetuses (16 and 17 weeks’ gestation) were studied histologically and immunohistochemically, digitized and reconstructed three‐dimensionally. 3D reconstruction allowed a ‘computer‐assisted dissection’, identifying the precise location and distribution of the pelvic nerve elements. Proximal (supra‐levator) and distal (infra‐levator) communications between the pudendal nerve and IHP were observed. By determining the nature of the nerve fibres using immunostaining, we were able to demonstrate that the hypogastric nerves and pelvic splanchnic nerves, which are classically considered purely sympathetic and parasympathetic, respectively, contain both adrenergic and cholinergic nerve fibres. The pelvic autonomic nervous system is more complex than previously thought, as adrenergic and cholinergic fibres were found to co‐exist in both ‘sympathetic’ and ‘parasympathetic’ nerves. This study is the first step to a 3D cartography of neurotransmitter distribution which could help in the selection of molecules to be used in the treatment of incontinence, erectile dysfunction and ejaculatory disorders.
Abstract Background Detailed knowledge of nerve distribution in the neurovascular bundle (NVB) is essential to preserve sexual function after prostatic surgery. Objective To identify the location as ...well as the type (adrenergic, cholinergic, and sensory) of nerve fibres within the NVB and to provide a three-dimensional (3D) representation of their structural relationship in the human male foetus. Design, setting, and participants Serial transverse sections were performed every 150–200 μm in the pelvic portion of six human male foetuses (15–20 wk of gestation). Sections were treated with histologic and immunohistochemical methods (hematin-eosin-safran, Luxol Fast Blue, immunolabelling of protein S100, vesicular acetylcholine transporter, tyrosine hydroxylase, calcitonin gene-related peptide, and substance P). The 3D pelvic reconstruction was obtained from digitised serial sections using WinSurf software. Measurements NVB nerve location and type were evaluated qualitatively. Results and limitations The 3D reconstruction allowed precise identification of pelvic organ innervation. Nerve fibres derived from the inferior hypogastric plexus followed two courses: posterior and lateral, providing cholinergic, adrenergic, and sensory innervation to seminal vesicles, vas deferens, prostate, and urethral sphincter. Cavernous nerve fibres did not strictly follow the NVB course; they were distributed at several levels, in a fanlike formation. The main limitations of this study were the limited number of specimens available due to legal restriction and the time-consuming nature of the manually performed stages in the method. Conclusions The distribution of nerve fibres within the posterolateral prostatic NVB and the existence of mixed innervation in the posterior and lateral fibre courses at the level of the prostate and seminal vesicles give us an insight into how to minimise effects on sexual function during prostatic surgery. The 3D computer-assisted anatomic dissection represents an original method of applying anatomic knowledge to surgical technique to improve nerve preservation and decrease postoperative sexual complications.
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