Human penile ossification

True human penile ossification is rare. We report such a case with roentgenologic evidence and histologic confirmation, and we offer some comments concerning etiology.     

Human penile ossification. A case report

A 53-year-old man had suffered from plastic induration of the penis (Peyronie's disease) for 4 years. The firm plaque surgically removed from the proximal dorsal part of the penis showed bone formation at histologic examination.     

Human papillomavirus-associated penile squamous cell carcinoma in HIV-positive patients.

Two cases of penile squamous cell carcinoma with distinctive clinicopathologic characteristics are presented. The tumors appeared in patients infected with HIV and were located in the glans of the penis. Histologically, the neoplasms were well-differentiated, infiltrating, squamous cell carcinomas. The entire spectrum from benign condyloma to infiltrative squamous cell carcinoma was present in the two patients. In both cases, human papillomavirus (HPV) could be demonstrated using polymerase chain reaction analysis. The reported cases suggest a synergic interaction of HPV and HIV in the carcinogenic process of some penile carcinomas.     

Human penile hemodynamics by Xenon-133 clearance method in physiological erection.

We measured penile blood flow during physiological erection using the Xenon-133 clearance method in order to diagnose the exact cause of impotence. In 16 patients, in whom complete erection was obtained after visual sexual stimulation, the mean penile blood flow during erection was apparently higher than that in the flaccid state. On the contrary, in 6 patients whose reaction to visual stimulation was poor, penile blood flow did not change before and after stimulation. We considered that increased arterial flow was indispensable, but complete venous outlet obstruction was not necessary to produce a rigid erection. In addition, in the flaccid state the mean penile blood flow in the poor response group was apparently higher than that in the response group. This means that some patients who fail to obtain sufficient erection after visual sexual stimulation have increased venous outflow from the corpus cavernosum in the flaccid state. Based on these findings, the main cause of erectile dysfunction in such cases is probably attributed to disorders of the venous outlet system in the cavernous body.     

Human penile hemodynamics studied by a polarographic method

Observations of the tissue oxygen tension alteration were made using an open tip type oxygen electrode polarographic method as an index of blood flow change in the penile skin, corpus cavernosum and thigh skin of 16 males aged 20-26 years (average age: 20.5 years). In another five males aged 18-21 (average age: 19.8 years) the relationship between corpus cavernosum tissue oxygen tension alteration and penile circumference change in the erection process was observed. This relation was obtained in the penile circulation model, and penile hemodynamics were ascertained. In the flaccid penis the corpus cavernosum contains low-oxygen blood and there is a blockade at the vascular tree in the corpus cavernosum. In the tumescence phase the blood flow of the corpus cavernosum increased suddenly by the relief of cavernosum vascular blockade. During the penile tumescence phase the increased inflow and outflow persisted in corpus cavernosum, and in penile skin the blood also increased initially, but gradually decreased as penile circumference increased. After erection was attained it is thought that resistance to inflow occurred by outflow pathway contraction. In the detumescence phase, a decrease of inflow and a concomitant increase of outflow occurred and the reopening of outflow is thought to be necessary for prompt penile detumescence.     

The physiology of penile erection. I. Hemodynamics of penile erection

Arterial and venous flow and pressure studies of the corpora cavernosa were performed to elucidate the hemodynamics of canine penile erection. Being able to induce erection by electrical stimulation we were able to study the functionally relevant parameters at different stages of penile erection. From our results we conclude that penile erection can be subdivided in 5 phases: (1) latent-, (2) tumescence-, (3) erection-, (4) rigidity- and (5) detumescence phase. Furthermore, a differentiation of these subdivisions is made by observing at the mechanism of the 5 different stages: phase 1 to 4 is an active phenomenon, the detumescence phase is passive only.     

The physiology of penile erection. II. Neurophysiology of penile erection

Selective cavernous and pudendal nerve stimulation enabled us to study the neurophysiologic-/neurovascular mechanisms of penile erection in 6 monkeys. Corporeal pressure recordings during different neurostimulation patterns demonstrated that tumescence and erection are controlled by the autonomic nervous system (Nn. cavernosi) and has to be understood as the vascular phase of erection. However, rigidity is related to the muscle tone of the striated bulbospongiosus and ischiocavernosus muscles which are innervated by somatomotoric fibers of the pudendal nerve. This mechanism is defined as the muscular phase of penile erection.     

Transmission of penile cuff pressure to the penile urethra.

PURPOSE: We developed a noninvasive method to measure voiding bladder pressure by inflating a penile cuff to interrupt flow. We tested the underlying assumption that cuff pressure is transmitted to the penile urethra. MATERIALS AND METHODS: In 35 men we simultaneously recorded penile cuff and urethral pressure during 2 experimental protocols for 6 cuffs of various widths and manufactures. Initially a urethral pressure transducer was placed at the mid point of the cuff and urethral pressure was continuously recorded during cuff inflation. In experiment 2 cuff pressure was set at 120 cm. water and the urethral pressure profile was measured by withdrawing the urethral transducer through the cuff width. RESULTS: There was excellent agreement of cuff with urethral pressure over the range of 0 to 200 cm. water for cuffs 37 to 54 mm. wide. Narrower cuffs showed wider variation with less efficient transmission of cuff pressure to the urethral lumen. Similarly maximum pressure in the urethral pressure profile showed best agreement for cuffs 38 and 46 mm. wide. Wider cuffs produced higher and narrower cuffs produced lower transmitted pressure within the urethra. Cuff performance was also related to penile size. Results had good within-subject repeatability. CONCLUSIONS: We demonstrated that pressure transmission from cuff to urethra is optimal at a cuff width of 40 to 50 mm. and recommended this width for other investigations of noninvasive bladder pressure measurement.     

Corporeal penile plication for correction of erectile penile deformity.

Penile curvature causing functional impairment of sexual intercourse is uncommon but a number of patients are significantly inconvenienced by this condition. Seven patients who had marked erectile deviation were treated with surgical plication for their penile deformity. Mean follow-up was 16 months (range 3-48 months) and no postoperative complications were encountered. In six cases the penis has remained straight. In one patient recurrence of deformity occurred 12 months after corporeal plication. The simplicity of the corporeal plication technique with the low incidence of associated complications makes it an attractive surgical alternative for the treatment of penile erectile deformity.     

Nomogram for penile biothesiometry.

Three hundred and fifty men, aged between 17 and 80 years, with normal sexual anamnesis and without any neurological pathology, underwent finger (index) and penile biothesiometry using a biothesiometer. Tabular and graphical nomograms were obtained according to age and instrumental values. The use of the above-mentioned nomograms is an effective aid in detecting each individual case.     

Rhinosporidiosis mimicking penile malignancy.

Rhinosporidiosis is a chronic infection which is endemic in India and Sri Lanka. Penile involvement in rhinosporidiosis is rare and we report one such case. The pathology, treatment and possible etiology of the condition are reviewed.     

Ectopic ossification after hip arthroplasty.

The incidence of radiographically visible ectopic ossification around the hip joint was redorded in 145 hip joints of 132 patients treated by endoprosthetic replacement. There were 56 total hip replacements with a McKee-Farrar and 39 with a Brunswik type of endoprosthesis; in a further 50 hips the femoral head was replaced with a Moore or Thompson prosthesis. An identical antero-lateral surgical approach was used in all, without detachment of the greater torchanter. The patients were re-examined 3, 6, and12 months after the operation. The extent of ectopic ossification was graded from 0 to III and correlated with pain and with the function and mobility of the operated hip. Ectopic ossification of varied extent was recorded in 37 % after total hip replacement and in 38 % after replacement of the femoral head. Of these ossifications 95 % were recognizable within 3 months; they did not increase in size, but often in density during the following months. One case of bony ankylosis was noted. Ectopic ossification of slight (grade I) to moderate (grade II) degree did not cause pain or affect the function of the operated hip, but reduced the mobility of the affected hip. The difference in mobility between grade I and grade II was significant (p less than 0.05), and between grade 0 and grade II highly significant (p less than 0.001).     

Human penile erection and organic impotence: normal histology and histopathology

A very large amount of human material (7 embryos, 12 stillborns, 12 penes of males aged between 2 and 86 years, as well as bioptical material from 80 subjects affected by impotence problems) has been examined so as to study the penis arterial and venous walls, the blood flow regulation mechanisms and the intracavernal trabecular morphology. The amount of muscle tissue and of collagenous connective tissue has been numerically quantified by computer-assisted methods. This study enables the authors to underline three fundamental facts: (a) it confirms the normal penile erection mechanism, and the consequent theory, (b) it confirms that vascular sclerosis is a systemic phenomenon correlated to age, and that the penis is not exempt, and (c) in the case of impotence problems, the same sclerosis phenomenon may appear at an earlier age, and therefore induce pathological impotence.     

Lumbosacral intradural periradicular ossification. Case report.

Intrathecal ossification causing progressive myelopathy or radiculopathy does not occur frequently. The majority of the reported lesions have been in the thoracic spine and seldom in the sacral canal. This report presents the occurrence of disabling low backache and sciatica from intradural periradicular ossification in the lumbosacral region in a previously healthy man.     

Treatment of congenital penile curvature with penile torsion: a new twist.

Congenital penile curvature secondary to asymmetry of corpora cavernosal length is an uncommon cause of penile deformity. Although the deformity generally is not severe enough to preclude sexual intercourse it can be a source of great concern to the patient and may cause him to avoid all sexual contact. The Nesbit procedure is a simple, effective surgical technique to correct lateral or ventral curvature. Rarely penile deviation is accompanied by penile torsion. This unique problem requires a novel surgical approach to create a straight, nontwisted erection. We report 2 cases of congenital lateral penile curvature with accompanying penile torsion and describe a simple modification of the Nesbit procedure for surgical correction.     

Predicting penile size during erection.

The aim of this prospective study was to identify clinical and engineering parameters of the flaccid penis for prediction of penile size during erection. Dorsal and ventral penile lengths, as well as base and tip circumferences were measured in flaccid states, gently stretched states and at full erection resulting from intracavernosal injection of prostaglandin E1 in 55 patients. The forces required to stretch the penis were measured by a specially designed gauge and regression relationships of the measured dimensions were calculated. An engineering model was developed to analyze differences between results obtained during stretching and erection, as well as to approximate the optimal force values which should be applied during the stretching part of the clinical evaluation of penile size. The ratio between the flaccid to stretched penile lengths was shown to be the best predictor for the ventral elongation from flaccid to erect penile lengths. The engineering analysis predicted that a minimal tension force of approximately 450 g during stretching of the penis is required to reach the potential erection length. The stretching forces exerted by the urologist in the clinical setting were experimentally shown to be significantly (P<0.01) less than this value. The values of the relative and absolute elongations of the stretched penis at its ventral aspect provide reliable estimations of its potential maximal elongation during erection. The model designed for this study may obviate the use of intracavernosal injections for estimating penile length during erection.     

Complications of Small-Carrion penile prosthesis.

Seventy-six patients with impotence have undergone insertion of the Small-Carrion penile prosthesis at Duke University Medical Center. Twenty patients experienced postoperative complications. Seven of these 20 patients lost one or both prostheses either by spontaneous extrusion or surgical removal. Although success with this procedure is well documented, complications may be significant when they occur and awareness of these problems is essential for proper management. The benefits of this procedure are reviewed, and reported complications and their management are discussed.