Espatulas de thierry versus forceps de kjelland

Presentamos la experiencia y evolución del parto instrumentado en nuestro Servicio de Obstetricia y Ginecología, en los últimos once años 1992-2002. La evidencia demostró que respecto de las lesiones maternas y fetales, las Espátulas (ET), o instrumento no articulado de la clasificación general de los fórceps (F), son significativamente menores cuando se las compara con el fórceps articulado y fenestrado de Kjelland o Kielland (FK), por lo que se sugiere su conocimiento y adiestramiento en los Servicios de la especialidad, y cambiar el concepto de la presa del cráneo-fetal o biparieto malar por la toma libre facio malar.

Hydrodynamic assessment of efferent limb valve mechanisms in continent urinary diversion: comparative study on a cadaveric model.

Various valve mechanisms, customarily employed in continent urinary diversion, were constructed from fresh cadaveric porcine bowel for later urodynamic assessment. A total of six different types of valves were formed from ileum or colon in varying lengths and tested by volume pressure trials. The leak point or maximum pressure were recorded at constant perfusion rates of 30 ml/min of the constructed reservoir. Ileal or colonic nipple valves, as well as the embedded or pulled-through ileum, tapered to 12 F at a length of 3 cm, withstood maximum pressures ranging between 75 and 138 cm H2O before leakage or protrusion of the valve occurred. Plicated or tapered terminal ileum in caecal reservoir revealed water leakage at pressures as low as 25 to 40 cm H2O. A newly-developed valve mechanism consisting of a 12 F, plicated colonic-serosal tunnel with a minimum intra-reservoir length of 5 cm resisted maximum pressures of more than 70 cm H2O. Our cadaveric porcine bowel model proved to be reliable for acute volume/pressure trials and correlated with all clinical urodynamic results and animal trials. It is simple, inexpensive and allows scope for individual ideas before commencing with animal trials.

Basic experimental studies on corpus cavernosum electromyography and smooth-muscle electromyography of the urinary bladder.

In contrast to the extensive work on in vitro experiments for elucidation of the electrical properties of smooth musculature, the acquisition of knowledge on electrical signal behaviour from smooth-muscle cells in an in vivo situation remains very limited and rare. Smooth-muscle electromyographic recording from the smooth musculature of the genitourinary tract, in particular from the penile cavernous bodies and the urinary bladder, has recently become one of the most interesting issues in both impotence research as well as neurophysiological assessment of the urinary bladder. However, the inadequate available data on corpus cavernosum and EMG recordings remains controversial due to the significant discrepancy between basic physiology of the smooth musculature, technical prerequisites and the expected clinical impact from the smooth-muscle EMG of genitourinary organs. This article is an attempt to describe the fundamentals of smooth-muscle EMG signal behaviour and the technical prerequisites for data acquisition and analysis of electrical activity from smooth-muscle cells of the cavernous bodies and urinary bladder. A description is given of the technical aspects, including methodology and interpretation of the recorded data, and also of the possible interference by artefacts (endogeneous and exogeneous) that might limit the clinical relevance of this encouraging method. The advantages, pitfalls and limitations of online analogous data registration and the possibility of computer-assisted smooth-muscle electrical activity recording and analysis are demonstrated by basic in vivo studies on cavernous bodies and also the detrusor muscle.

Comparison of urodynamic findings and response to oxybutynin in nocturnal enuresis.

Sixty-three children with persistent nocturnal enuresis were urodynamically assessed and subsequently treated with oxybutynin chloride. Urodynamic evaluation, including graduation of detrusor instability and comparison of maximum bladder capacity with the age-predicted norm, confirmed an inadequate storage function in 84% of the children. Treatment benefit totaling 70% was dependent upon urodynamic findings, with best relation to the determined bladder capacity. The value attributed to graduation of uninhibited contractions was prognostic in accordance with further subdivision of the maximum bladder capacity. Treatment benefit was limited in children with normal urodynamic findings.

Correction of distal hypospadias: ventral adaption of the prepuce and meatal advancement.

In distal hypospadias without chordee, surgical correction has a purely cosmetic character. In contrast to standard techniques focusing on meatal position, parents often regard the redundant dorsal prepuce and its missing ventral fusion as the essential constituent of this malformation. The operative technique, presented in detail, emphasizes on foreskin reconstruction. The ventral adaption of the prepuce (VAP procedure) results in a penis with normal appearance. Complications presented reveal the importance of proper patient selection.

The effect of impaired lipid metabolism on the smooth muscle cells of rabbits.

Our clinical data enabled us to demonstrate a correlation between impaired lipid metabolism and vasculogenic impotent men. Our aim was to evaluate the effect of an impaired lipid metabolism on the smooth muscle of the corpus cavernosum. A total of 16 rabbits were given a cholesterol-enriched diet for 3 months, and 8 of these received additional thromboxane A2 receptor antagonist; 10 other rabbits (control) were fed a normal diet. Subsequently, cavernous tissue biopsies were taken, and tissue lipid extractions and electron microscopic evaluation were made from 3 rabbits in each group. In the untreated high-cholesterol diet group, cholesterol levels reached approx. 2.1 micrograms/mg body weight compared with 1.07 micrograms/mg b.wt. in the thromboxane A2 receptor antagonist-treated group and elevated levels compared with control group. Similar results were found for the triglyceride and free fatty acid levels. Lecithin tissue levels in treated rabbits were distinctly elevated against those of other 2 groups. Ultramorphological examination of the control group disclosed normal smooth muscle cell (SMC) architecture with numerous sites of intercellular contacts. These findings contrasted with those of the high-cholesterol diet groups which showed significant SMC degeneration with loss of intercellular contacts. Our data imply that impaired lipid metabolism causes cavernous SMC degeneration which plays a major role in the pathogenesis of erectile dysfunction. The thromboxane A2 receptor antagonist seems to produce a protective metabolic effect on the erectile tissue which may have some consequences future treatment strategies.

Neurophysiological aspects of penile erection: the role of the sympathetic nervous system.

Recent studies have revealed that the initiation, maintenance and rigidity of penile erection are under parasympathetic and somatotopic control. The mechanism of penile detumescence is still under debate. Single and combined cavernous and hypogastric nerve stimulation was used to study the influence of the sympathetic nervous system on penile erection and to identify the mechanism of penile detumescence. Penile arterial flow and intracorporeal pressure recordings during various stimulation patterns indicated that erection induced by stimulation of the cavernous nerve could be blocked by excitation of the upper hypogastric nerves. Venous outflow studies demonstrated that the inhibitory effect of the sympathetic nervous system was due to active vaso- and corporeal smooth muscle constriction. It was concluded that subsidence and suppression of erection is a sympathetic function. Previous studies have shown that the neurophysiology of erection can be explained by 3 major inhibitory (sympathetic). Our findings are of clinical importance, since a better appreciation of the basic erectile mechanism is essential for successful management of erectile dysfunction.

[Diagnosis of a venous fistula as a cause of erection disorders. Experimental principles and practical conclusions]. / Die Diagnose des venösen Lecks als Ursache von Erektionsstörungen. Experimentelle Grundlagen und praktische Schlussfolgerungen.

An experimental study was done in ten dogs and eight monkeys to evaluate the accuracy of dynamic and pharmacologic cavernosometry and cavernosography in the diagnosis of venogenic impotence. Our findings show that erection induced by saline perfusion comes about because the penile venous outflow capacity is exceeded. Thus, the cavernous occlusive mechanisms are not activated. Cavernosography in induced erection always demonstrated the entire cavernous venous system. However, cavernosometry after pharmacologic cavernous smooth muscle relaxation provides useful diagnostic information. Similarly, cavernosography after pharmacologic cavernous smooth muscle relaxation proved to be useful for the identification of abnormally draining veins.

Neurophysiology of penile erection.

In 6 dogs and 6 monkeys electrical stimulation of the cavernous, pudendal and hypogastric nerve was performed to gain better understanding of the erectile neurophysiology. Arterial flow, intracorporeal pressure and venous restriction studies during single and combined neurostimulation demonstrated that initiation and maintenance of erection is a parasympathetic phenomenon. Penile rigidity however, could only be achieved with additional pudendal nerve stimulation resulting in muscular compression of the blood distended cavernous bodies. Detumescence or subsidence of erection is primarily under sympathetic control, due to inhibition of sinusoidal smooth muscle relaxation. On the basis of our observations we conclude that penile erection is dependent upon three neurophysiological mechanisms: 1. the parasympathetic "vascular mechanism", the somatomotor "muscular mechanism" and the sympathetic "inhibitory mechanism".