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Biomedical subjects

V Delmas

Publications and source records attributed to V Delmas.

At least 19 recordsLinked to original sources

Morphometry by computerized three-dimensional reconstruction of the human carpal bones during embryogenesis.

Carpal skeleton shows drastic developmental changes during embryogenesis. At this stage, the cartilaginous matrices appear and later form models of the limb bones. The purpose of this study was to investigate the morphometry of carpal bones in humans during embryological development. We obtained digitalized histological serial sections of 18 human embryos and early fetuses from the Institute of Anatomy in Paris. Surfdriver and MSC.Patran software were used for three-dimensional reconstruction and morphometry. There was a strong correlation between the volume of the carpal cartilaginous structure and the size of the embryos (P<0.001) and an exponential correlation between the carpal volume and the percentage of volume presented by the proximal carpal row (P=0.005). According to inertia parameters, the geometry of carpal cartilaginous structure, initially plane, becomes curved during embryogenesis. Carpal bones growth follows non-homothetic transformation. The innovations in embryo reconstruction serve as new tool for scientific investigation. A hypothesis of carpal development is proposed.

Adult↗

[3D modeling in the field of morphology: methods, interest and results].

The aim of this paper is to show the major role played by the new computerized imaging tools available today in the fields of morphology and anatomy. For anatomical studies or educational purpose, they enhance the classical techniques. The 3D reconstruction, already used in daily clinical practice, will be the basis for computation of validated volumetric protocols enhancing our diagnosis and prognosis means. It is also a fantastic educational tool: the interactivity makes it simple, efficient, attractive and easily accessible and diffusable. For the research, mathematical modeling of embryogenesis and morphogenesis using finite elements method will open new ways for biomecanics and a dynamic quantification approach.

Computer Simulation↗

Renal lymphatic drainage and thoracic duct connections: implications for cancer spread.

Studies on renal lymph drainage have generally described lymph nodes without further investigation of the lymph vessels. Our purpose was to revisit this organ to study the vessel drainage pattern. This investigation was performed on 16 refrigerated adult cadavers. After both kidneys were injected with a blue modified Gerota mass, lymph vessels were dissected until their termination. From the right kidneys (n = 13), lymphatics (n = 8) traveling on the anterior aspect of the inferior vena cava were dissected, reaching interaortocaval and more distant nodes, aorta bifurcation (n = 1) and left lateroaortic (n = 1); posterior lymphatics were observed in all subjects, uniformly connecting to the thoracic duct, either after crossing nodes (n = 8) or directly (n = 5). From the left kidneys (n = 13), anterior efferents (n = 16) were dissected, reaching left lateroaortic and also celiac (n = 4) and iliac (n = 1) nodes; posterior lymphatics were also demonstrated, always connecting to the thoracic duct (3 directly). Renal lymphatics have been found to reach very distant nodes as well as always connecting to the origin of the thoracic duct. This feature suggests an important role in both the formation of the thoracic duct and in the spread of renal cancer.

Adult↗

Anatomical risks of transobturator suburethral tape in the treatment of female stress urinary incontinence.

INTRODUCTION: The objective of this study was to define the anatomical structures crossed by transobturator tape. MATERIALS: Ten fresh, female anatomical subjects aged 74 to 89 years. METHODS: Transobturator tape was inserted by outside-in way. The position of the tape was verified by perineal and abdominal dissection. RESULTS: Transobturator tape has a transverse course. It crosses the adductor muscles close to their pubic insertion and passes over the inferior border of the obturator foramen by crossing the obturator membrane, before reaching the middle plane of the perineum after having crossed the obturator internus muscle. The tape passes above the internal pudendal pedicle and then under the levator ani muscle, under the tendinous arch of the pelvic fascia and continues in the middle third of the urethrovaginal septum. It avoids femoral and obturator vessels in the thigh and pudendal vessels in the perineum. CONCLUSION: The anatomical course of transobturator tape shows that the anatomical structures crossed by the tape are muscle and fascia and, when the technique is performed correctly, no major neurovascular structures are in contact with the tape.

Aged↗

The structure and innervation of the male urethra: histological and immunohistochemical studies with three-dimensional reconstruction.

The structure of the striated urethral sphincter, the so-called rhabdosphincter, remains the subject of controversy. There are two main concepts regarding its structure: either it is a part of the urogenital diaphragm, or it extends from the base of the bladder up to the urogenital diaphragm and is an integral part of the urethra. It is also uncertain whether it possesses a somatic innervation or a mixed innervation (i.e. autonomic and somatic). The purpose of this study was to show the precise location of the nerves running to the urethra, and to try to determine their exact nature. Histology and immunohistochemistry were performed in the external urethral sphincter of ten male fetuses (114-342 mm crown-rump length, or between 14 and 40 weeks of gestation). A three-dimensional (3D) reconstruction of the urethral structure and its innervation was made from serial sections. The 3D reconstruction of the same section levels with different strains allowed us to identify the precise structure of the muscle layers (smooth and striated muscle fibres) and the nature of the nerve elements (myelinated and unmyelinated), their distributions and their relationship to the urethral wall, the prostate and the seminal vesicles. Histological and immunohistochemical 3D reconstruction of the anatomical elements of the urethral sphincter helps us to understand the 3D arrangement of the sphincter muscle layers. It also provides a better understanding of the origin and nature of the nerve elements that play a role in urinary continence.

Gestational Age↗

Going back to dissection in a medical curriculum: the paradigm of Necker-Enfants Malades.

In 1999, we first reported on various methods of teaching anatomy subsequent to visits to a variety of medical schools in the United States and Europe. We compared the number of contact hours for lectures, dissection classes and tutorials and provided different models for the teaching of anatomy. With respect to the nine French medical schools surveyed, it is clear that the French model is characterized by being lecture-orientated (time in lectures > time in tutorials > time spent on dissection). For the American model (also in the UK and some other parts of Europe), the training is often characterized by being dissection-based (time spent on dissection > time in lectures > time in tutorials; 10 medical schools surveyed). Exceptionally, in one Australian school, time in tutorials exceeds time in lectures (dissection = 0). The differences between the French and American models relate to teaching aims-where dissection predominates, the aims are not just the learning of anatomical facts but include practical skill acquisition and experiential learning. In 2001, to help us change the methods of teaching of anatomy in our medical school at CHU Necker-Enfants Malades (Paris V, France), we asked other French medical schools (and some foreign schools) to suggest ways of organizing anatomy training within certain time constraints. In this paper, we present the answers received. The responses received were of two kinds: (1) those providing a description of the anatomy teaching in their own medical school; (2) those providing a system for organizing the teaching if we, in Paris, have 120 hours in total to teach gross anatomy (except neuroanatomy). In the latter case, a considerable variety of different, and innovative, alternative schemes were suggested that are described in this article.

Anatomy↗

Surgical treatment of female stress urinary incontinence with a trans-obturator-tape (T.O.T.) Uratape: short term results of a prospective multicentric study.

OBJECTIVE: The aim of the study was to assess the efficacy and safety of a new minimally invasive surgical procedure using the Trans-Obturator-Tape Uratape to treat female stress urinary incontinence. PATIENTS AND METHODS: 183 women with stress urinary incontinence (SUI) associated with urethral hypermobility, underwent the T.O.T. procedure (October 2001 to March 2003). 26 patients were previously operated for incontinence. 26 patients were operated at the same time for their genital prolapse. Mean age was 56 years (29-87). 50/183 patients were having mixed incontinence. A non-elastic, polypropylene tape (UraTape, Mentor-Porgès) with a silicon coated central part was placed under the mid-urethra. The surgical placement technique utilises a trans-obturator percutaneous approach. All patients underwent post-operative clinical examination, cough-stress test (full bladder), uroflowmetry, and post-voiding residual assessment. RESULTS: Mean follow-up was 7 months (1-21). At 1 year follow-up 80.5% of the patients were completely cured and 7.5% were improved. The overall peri-operative complication rate was 2.2% with no vascular, nerve or bowel injury. 6 patients (3.3%) had post-operative urinary retention. CONCLUSION: The present multicentric study confirms the results obtained by the instigator of the technique, E. Delorme, and allows us to consider T.O.T. as an effective and safe technique for the treatment of female stress urinary incontinence, alone or in combination with prolapse repair.

Adult↗

The retrograde neurocutaneous island flap of the dorsal branch of the ulnar nerve: anatomical basis and clinical application.

It is well known that a cutaneous artery is constantly located near a cutaneous peripheral nerve, forming a vascular plexus around it. This vascular axis can be either a true artery or an interlacing network, ensuring the vascularization of the nerve and giving off several neurocutaneous perforators to the skin. The anatomy of the accompanying arteries of the dorsal branch of the ulnar nerve (DBUN) and their relationships with the dorsal branch of the ulnar artery (DBUA) were investigated in 22 fresh upper limbs injected with colored neoprene latex. A constant perineural vascularization of the terminal branch of the DBUN was observed in the fourth web space, connected distally with the corresponding dorsal metacarpal or palmar digital arteries. Our findings therefore provide anatomical bases for a new neurocutaneous island flap. Moreover, they allow us to describe a precise surgical technique in order to raise this flap over the larger branch of the DBUN, in the fourth intermetacarpal space. The flap is harvested on the medial aspect of the dorsum of the hand, and its point of rotation is located in the fourth web space, 1 cm proximal to the metacarpophalangeal joint. It is supplied by a reversed flow originating from distal anastomoses of the perineural vessel with the dorsal metacarpal and digital palmar arteries in the fourth web space. This flap does not involve in its pedicle the distal course of the DBUA. It represents a pure neurocutaneous flap.

Aged↗

Classical and nerve-sparing radical hysterectomy: an evaluation of the risk of injury to the autonomous pelvic nerves.

Radical hysterectomy represents the treatment of choice for FIGO stage IA2-IIA cervical cancer. It is associated with several serious complications such as urinary and anorectal dysfunction due to surgical trauma to the autonomous nervous system. In order to determine those surgical steps involving the risk of nerve injury during both classical and nerve-sparing radical hysterectomy, we investigated the relationships between pelvic fascial, vascular and nervous structures in a large series of embalmed and fresh female cadavers. We showed that the extent of potential denervation after classical radical hysterectomy is directly correlated with the radicality of the operation. The surgical steps that carry a high risk of nerve injury are the resection of the uterosacral and vesicouterine ligaments and of the paracervix. A nerve-sparing approach to radical hysterectomy for cervical cancer is feasible if specific resection limits, such as the deep uterine vein, are carefully identified and respected. However, a nerve-sparing surgical effort should be balanced with the oncological priorities of removal of disease and all its potential routes of local spread.

Aged↗

Morphometry by computerized three-dimensional reconstruction of the hypogastric plexus of a human fetus.

The histological study of the plexus hypogastricus inferior (hypogastric plexus) of a human fetus does not permit the direct appreciation of its spatial configuration and its complicated relations. Developments in the field of computer science and three-dimensional (3D) reconstruction from serial histological sections have allowed a precise description of its morphometry and relations. The histological sections which were used came from the "Rouvière" collection of the Institute of Anatomy in Paris. A personal computer (IMAC) system of image analysis with reconstruction software was used. Serial pelvic histological sections were directly digitized from the slides. Image treatment and reconstruction were done with manual methods. The 3D reconstruction of the hypogastric plexus, the nerves, the pelvic skeleton and viscera were done. The hypogastric plexus and its topographic relations with the other organs were visualized and studied in three dimensions, and its morphometry was studied. The direct acquisition of the images from the slides allowed excellent high-quality digital images to be obtained. However, manual processing for the reconstruction was time-consuming. At first, the reconstruction of the various pelvic structures was done separately for each organ. Then the structures were visualized all together. Thus, the hypogastric plexus could be examined under various incidences with each organ. The virtual images obtained show new details of the topographic relations and improve knowledge of the precise innervation of the pelvic organs.

Female↗

An operative and anatomic study to help in nerve sparing during laparoscopic and robotic radical prostatectomy.

OBJECTIVE: To provide a detailed description of the steps involved in a laparoscopic radical prostatectomy in relation to the complex neurovascular anatomy of the male pelvis. AIM AND HYPOTHESIS: We aimed at delineating the neurovascular anatomy to assist in nerve preservation during laparoscopic and robotic radical prostatectomies. METHODS: A team of urologists and an anatomist performed anatomic dissections of 12 male cadavers using a combination of laparoscopic equipment, magnification, and open surgical dissection. Each step involved in laparoscopic prostatectomy was reviewed in relation to the possible impact the step could have on the neurovascular bundles. RESULTS: Dissections were performed systematically to mimic various steps of laparoscopic and robotic prostatectomy. The neurovascular bundles were identified and correlated with video images of actual surgery. This enabled us to construct computer simulations and show the actual nerves on the operative pictures. We specially unraveled the relationship between neurovascular bundles and lateral pelvic and Denonvillier's fascias, both of which enclose and hide these important structures. The course of the bundles was traced from its origin at pelvic plexus to its distal course along the urethra. We also showed the important relationship between pelvic plexus ganglions and seminal vesicles to illustrate the vulnerability of these nerves to thermal, electrical and/or crush injury during seminal vesicle and prostatic pedicle dissections. The importance of additional fine neural plexus along the posterior and antero-lateral surface of the prostate was shown by both gross anatomical and microscopic images. The distal precarious location of the bundles was illustrated by dissections showing anteriorly lifted prostate.These anatomico-operative correlations have not been published for laparoscopic and robotic prostatectomies, which differ significantly in its visual angles, magnifications and sometimes three-dimensional (3D) visualization from its open counter part. CONCLUSION: Laparoscopic and robotic radical prostatectomy provides exposure and visualization of male pelvis not previously appreciated. It is only through a careful reexamination of the anatomy of the male pelvis, in the context of this new procedure, that the improvements in visualization and exposure benefit the surgeon. Our work provides a detailed map relating to operative steps to aid the surgeon in the performance of a nerve sparing robotic and laparoscopic radical prostatectomy.

Fascia↗

Celiac trunk compression by arcuate ligament and living-related liver transplantation: a two-step strategy for flow-induced enlargement of donor hepatic artery.

The median arcuate ligament is a tendinous arch joining the two medial borders of the diaphragm crura together. In 10-50% of subjects it is responsible for significant angiographic celiac trunk compression. In severe cases, a decrease in hepatic arterial blood flow with subsequent artery caliber reduction and reverse vascularization via the gastroduodenal artery is present. In liver transplantation, small-caliber hepatic arteries are higher risk factors for hepatic arterial thrombosis and frequent graft loss. We report a case of celiac trunk compression in a living-related donor and the two-step strategy we developed to perform a safer liver transplantation via flow-induced enlargement of the donor hepatic artery. A 29-year-old father was selected as a living-related liver donor for his 4-year-old daughter. Angiography revealed celiac trunk compression by the median arcuate ligament with reverse vascularization of the middle hepatic artery via the gastroduodenal artery, a proper hepatic artery 2 mm in diameter irrigating the left lateral segment exclusively, and a right hepatic artery irrigating the right lobe and segment 4. First-step division of the median arcuate ligament and gastroduodenal artery ligation were performed. Repeat angiography at the third week showed a 50% enlargement of the middle hepatic artery (3 mm). Second-step left lobectomy was performed at the fifth week. The transplantation was achieved with an arterial anastomosis between the middle hepatic arteries of donor and recipient. This two-step strategy including median arcuate ligament division provided flow-induced enlargement of the donor middle hepatic artery for a safer transplantation with arteries of more suitable calibers.

Adult↗

The human lumbar anterior epidural space: morphological comparison in adult and fetal specimens.

To increase our understanding of the clinical anatomy of the epidural space, the human lumbar anterior epidural space was studied morphologically and developmentally. Histological transverse sections of human lumbar spines were taken at the level of the intervertebral disc and the vertebral body in adult specimens and in fetuses aged 13, 15, 21, 32 and 39 weeks (menstrual age). At 13 weeks, connective tissue filled the epidural space. The dura mater was attached anteriorly to the posterior longitudinal ligament (PLL). The PLL was attached to the vertebral body beside the midline, whereas it adhered to the posterior edge of intervertebral disc. The anterior internal vertebral venous plexus was located anterolaterally and anteromedially. The vertebral canal was lined with connective tissue that differentiated in a periosteum in contact with the ossification centers. At 15 weeks, the PLL was composed of deep and superficial layers. At 21 weeks, the attachment between the dura mater and PLL was ligament-like at the level of the vertebral body. At 32 weeks, the dura mater was adherent to the superficial layer of PLL. At 39 weeks, groups of adipocytes were identified, and the dura mater was attached to the PLL by some ligaments. There were many more similarities between the adult and the 39-week fetus. In conclusion, some differences in the anatomy of the epidural space exist at each fetal stage studied. The structures of the epidural space are already formed in the fetus of 13 weeks, but they differentiate progressively within the connective tissue.

Dura Mater↗

[Innervation of Denonvilliers' recto-vesical septum. Anatomic study].

OBJECTIVE: The retro vesical septum (DENONVILLIERS) can be dissected and separated of the prostate and the bladder. The neurovascular bundles bound laterally this septum and it must be removed during radial prostatectomy. The aim of this study was to know if this septum is crossed by nerves. MATERIAL AND METHODS: Dissection of cadaver--histological study of recto-vesical fascia. RESULTS: Nerves are present coming from the neurovascular bundle to the septum and end in the prostate. CONCLUSION: These anatomical observations conduct to recommend to remove systematically the recto-vesical septum during radical prostatectomy for cancer.

Connective Tissue↗

IGF-II induces rapid beta-catenin relocation to the nucleus during epithelium to mesenchyme transition.

The epithelium to mesenchyme transition is thought to play a fundamental role during embryonic development and tumor progression. Loss of cell-cell adhesion and modification of both cell morphology and gene expression are the main events associated with this transition. There is a large amount of evidence suggesting that growth factors can initiate these events. Yet, the connection from growth factor induction to changes in cell adhesion and morphology is largely unknown. To elucidate this connection, we have investigated the action of IGF-II on E-cadherin/beta-catenin complex-mediated cell-cell adhesion and on beta-catenin/TCF-3 mediated gene expression. We can show that (1) IGF-II induces a rapid epithelium to mesenchymal transition; (2) IGF1R, the receptor for IGF-II, belongs to the same membrane complex as E-cadherin and beta-catenin; (3) IGF-II induces a redistribution of beta-catenin from the plasma membrane to the nucleus and an intracellular sequestration and degradation of E-cadherin; (4) IGF-II induces the transcription of beta-catenin/TCF-3 target genes. Based on the given case of IGF-II and E-cadherin/beta-catenin complex, this study reveals the backbone of a cascade connecting growth factor signaling with cell-cell adhesion during EMT.

3T3 Cells↗