Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Alt... more Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Although it is not beyond controversy, penile arterial revascularization surgery supports its utility in young males suffered from arterial trauma, and in the older male with localized arterial occlusive disease. Despite it is not agreed in most medical community, penile venous stripping surgery has been shown to be beneficial in correcting veno-occlusive dysfunction, with outstanding results. The traditional complications of irreversible penile numbness and deformity have been virtually negated with the venous ligation technique superseding venous cautery. Penile vascular surgery is viable although it is technically challenging.
We report the use of a modified rat model for the study of the mechanisms of penile erection. In ... more We report the use of a modified rat model for the study of the mechanisms of penile erection. In 92 Sprague-Dawley rats, the cavernous nerve was stimulated with different pulse intensities and frequencies, and the intracavernous pressure, time to maximal pressure and total duration of tumescence were measured. A maximal response was elicited at 20 pulses per second (pps) and 1.5 mA. Using this as 100%, we determined the relative pressure responses obtained with other frequencies: 5 pps, 57.3% (p = 0.007), 10 pps, 84.9% (p = 0.043); 30 pps, 99.5% (p = 0.832); 40 pps, 97.8% (p = 0.168); 50 pps, 90.9% (p = 0.021); 100 pps, 76.1% (p < 0.001). The time to maximal pressure varied with different frequencies, but was in all cases significantly different from the 20-pps response. Erection time during continuous cavernous nerve stimulation was significantly longer with frequencies below 20 pps (10 and 5 pps). In 30 rats, the physiologic response to intracavernous injection (0.03 ml) of acetylcholine, atropine, guanethidine, norepinephrine, phenylephrine, papaverine, terbutaline (intravenous also) and phentolamine was measured. Papaverine caused a dose-dependent rise in pressure; acetylcholine, atropine (a parasympathetic blocking agent) and guanethidine all had minimal effects. Phentolamine and norepinephrine increased systemic blood pressure, whereas phenylephrine decreased the intracavernous pressure in response to electrostimulation significantly.(ABSTRACT TRUNCATED AT 250 WORDS)
In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of d... more In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of deep dorsal vein arterializatio11 with in1plantation of an inflatable ""v"enous compression device. The device was placed around the proximal corpora cavernosa, sparing the left dorsal artery. A left-to-right, end-to-side dorsal artery-dorsal vein fistula was fashioned, and the right dorsal vein was anastomosed to the corpus cavernosum as an end-to-side venocorporeal window. From postoperative day 15, the device was activated twice a day for 3 months. Intracavernous pressure (bilateral) and left dorsal artery blood flow were monitored, and the patency of the anastomoses was evaluated by vascular clamping, arteriography, cavernosography and microscopic dissection. The device was well-tolerated, requiring no anesthesia during activation. (A sixth dog developed glanular hyperemia and priapism and was excluded from evaluation.) With cuff inflation, the intracavernous pressure was significantly higher on the experimental side (range, 20 to 106 cm. H20 higher; p = 0.028), and arteriography demonstrated contrast flowing in the fistula and window in 3
Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral r... more Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral roots, Landmarks for identification of the roots were developed; bladder, urethral and intracavernous pressures were recorded; and tail and leg movements were checked, Urethral sphincter contraction was elicited by stimulation of the Ls-L6 ventral roots, while bladder contraction and penile erection were mediated by the L6-S1 ventral roots, The best sphincteric response and intracavernous pressure rise were obtained by stimulation of the L6 ventral root, and the highest bladder pressures by stimulation of the 8 1 ventral root, Stimulation of the S1-S2 ventral roots provoked ipsilateral tail movement; of L6, tail movement, hindleg muscle twitch, and slight toe spread; and of Ls, hindleg stretch and plantar flexion, No significant differences were found between the two strains of rats, although a higher bladder pressure was recorded during stimulation of the L6 ventral root in Sprague-Dawley rats, which might be explained by a small caudal shift of the sacral parasympathetic nucleus in the Wistar strain,
Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction ... more Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction (VOD). From 2012 to 2016, refractory impotence prompted four men to seek further treatment, although they underwent six CEs elsewhere. Uncontrolled coils scattered along penile drainage veins including the deep dorsal veins (n = 3), periprostatic plexus (n = 1), iliac vein (n = 1), right pulmonary artery (n = 2), left pulmonary artery (n = 1), and right ventricle (n = 1). The last one occurred in a 40-year-old house builder, and the coil perforated the right ventricle wall and diaphragm 18 months later. Given no sustainable improvement, CE's safety and efficacy are unreliable for treating patients with VOD.
Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An ... more Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An obstructive aetiology is found in approximately 40% of azoospermic men. Of these, 30–67% have obstruction at the level of the epididymis. Th is study looks at the outcome of microsurgical epididymovasostomy in the management of obstructive azoospermia, specifi cally the patency and pregnancy rates aft er reconstruction. Patients and Methods: Th e outcome of the microsurgical epididymovasostomy procedures performed between 2000–2011 was retrospectively analysed. Azoospermic patients with normal testicular size, with or without epididymal dilatation, with a normal hormone profi le (FSH, LH, and Testosterone), normal male reproductive genetic profi le (XY), and a TRUS showing no evidence of ejaculatory duct obstruction, underwent scrotal exploration. An intraoperative vasogram was performed to exclude distal obstruction. Scrotal exploration was performed in 124 patients. Th e abscence of di...
Objective To investigate whether changes in the structure of the tunica albuginea influence the ... more Objective To investigate whether changes in the structure of the tunica albuginea influence the development of erectile dysfunction. Patients and methods Biopsy specimens taken from the tunica of 64 patients (both potent and impotent) with and without Peyronie's disease were evaluated. Tissue samples were stained and examined under light and electron microscopy, and the concentration of elastic fibres present in each was measured using computerized image analysis. Results The concentration of elastic fibres was lower in impotent than in potent patients (P=0.0365) and was also significantly less in patients with Peyronie's disease. Furthermore, the concentration of elastic fibres decreased with age. Electron and light microscopy revealed the presence of distinct alterations in the tunica albuginea in impotent patients and patients with Peyronie's disease that might interfere with function. Conclusion The decrease in elastic fibre concentration and changes in microscop...
We describe our experience with plaque excision and placement of a venous patch graft. Sprague Da... more We describe our experience with plaque excision and placement of a venous patch graft. Sprague Dawley rats (n = 20) underwent excision of a wedge of tunica albuginea with the defect covered by a segment of detubularized femoral vein, endothelial side towards the cavernous tissue. Erectile function, as determined by the rise in intracavernous pressure with cavernous nerve stimulation (mean 54.0 ± 4.2 cm. H 2 0), was equal to that in a group of 10 intact age-matched controls (mean 46.9 ± 3.37 cm. H 2 0). Penile cross-sections stained with Hart's elastic fiber stain or Trichrome stain revealed only minimal fibrosis in the region of the patch. In 3 dogs, a wedge of tunica was removed, and the defect was covered with a segment of detubularized deep dorsal vein. When sacrificed at 3 months, all animals had retained their erectile function with histologic evidence of minimal fibrosis. On the basis of histologic and functional data, the venous patch appears to be a reasonable alternative substance to those in common use.
Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance me... more Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance mediates nonadrenergic, noncholinergic relaxation of trabecular smooth muscle through activation of the cyclic guanosine monophosphate (cGMP) pathway. In 60 Sprague-Dawley rats, we investigated the effect of intracavernous administration of different drugs known to act at different levels of the cyclic adenosine monophosphate (cAMP) and cGMP pathways. Neither cAMP nor drugs that stimulate adenylate cyclase activity (vasoactive intestinal peptide, prostaglandin E1, calcitonin gene-related peptide) provoked any change in the basal intracavernous pressure. N-ethylmaleimide, an inhibitor of the enzyme adenylate cyclase, did not modify the response to electrostimulation of the cavernous nerve, indicating that the cAMP pathway does not play a significant role in penile erection in rats. However, intracavernous administration of methylene blue, a guanylate cyclase inhibitor, significantly reduced the response to electrostimulation (p = 0.001). Direct intracavernous injection of cGMP caused a statistically significant, dose-dependent increase in intravenous pressure that was not significantly inhibited by methylene blue. Sodium nitroprusside, a nitric oxide releaser and therefore a guanylate cyclase activator, caused a dose-dependent increase in intracavernous pressure (p < 0.05) that was inhibited almost completely by methylene blue (p = 0.002), supporting the theory that nitric oxide activates the synthesis of cGMP and that cGMP causes cavernous smooth muscle relaxation. Papaverine elicited an intracavernous pressure increase that was not affected by methylene blue or N-ethylmaleimide, indicating that papaverine acts through an independent pathway.(ABSTRACT TRUNCATED AT 250 WORDS)
Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Alt... more Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Although it is not beyond controversy, penile arterial revascularization surgery supports its utility in young males suffered from arterial trauma, and in the older male with localized arterial occlusive disease. Despite it is not agreed in most medical community, penile venous stripping surgery has been shown to be beneficial in correcting veno-occlusive dysfunction, with outstanding results. The traditional complications of irreversible penile numbness and deformity have been virtually negated with the venous ligation technique superseding venous cautery. Penile vascular surgery is viable although it is technically challenging.
We report the use of a modified rat model for the study of the mechanisms of penile erection. In ... more We report the use of a modified rat model for the study of the mechanisms of penile erection. In 92 Sprague-Dawley rats, the cavernous nerve was stimulated with different pulse intensities and frequencies, and the intracavernous pressure, time to maximal pressure and total duration of tumescence were measured. A maximal response was elicited at 20 pulses per second (pps) and 1.5 mA. Using this as 100%, we determined the relative pressure responses obtained with other frequencies: 5 pps, 57.3% (p = 0.007), 10 pps, 84.9% (p = 0.043); 30 pps, 99.5% (p = 0.832); 40 pps, 97.8% (p = 0.168); 50 pps, 90.9% (p = 0.021); 100 pps, 76.1% (p < 0.001). The time to maximal pressure varied with different frequencies, but was in all cases significantly different from the 20-pps response. Erection time during continuous cavernous nerve stimulation was significantly longer with frequencies below 20 pps (10 and 5 pps). In 30 rats, the physiologic response to intracavernous injection (0.03 ml) of acetylcholine, atropine, guanethidine, norepinephrine, phenylephrine, papaverine, terbutaline (intravenous also) and phentolamine was measured. Papaverine caused a dose-dependent rise in pressure; acetylcholine, atropine (a parasympathetic blocking agent) and guanethidine all had minimal effects. Phentolamine and norepinephrine increased systemic blood pressure, whereas phenylephrine decreased the intracavernous pressure in response to electrostimulation significantly.(ABSTRACT TRUNCATED AT 250 WORDS)
In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of d... more In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of deep dorsal vein arterializatio11 with in1plantation of an inflatable ""v"enous compression device. The device was placed around the proximal corpora cavernosa, sparing the left dorsal artery. A left-to-right, end-to-side dorsal artery-dorsal vein fistula was fashioned, and the right dorsal vein was anastomosed to the corpus cavernosum as an end-to-side venocorporeal window. From postoperative day 15, the device was activated twice a day for 3 months. Intracavernous pressure (bilateral) and left dorsal artery blood flow were monitored, and the patency of the anastomoses was evaluated by vascular clamping, arteriography, cavernosography and microscopic dissection. The device was well-tolerated, requiring no anesthesia during activation. (A sixth dog developed glanular hyperemia and priapism and was excluded from evaluation.) With cuff inflation, the intracavernous pressure was significantly higher on the experimental side (range, 20 to 106 cm. H20 higher; p = 0.028), and arteriography demonstrated contrast flowing in the fistula and window in 3
Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral r... more Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral roots, Landmarks for identification of the roots were developed; bladder, urethral and intracavernous pressures were recorded; and tail and leg movements were checked, Urethral sphincter contraction was elicited by stimulation of the Ls-L6 ventral roots, while bladder contraction and penile erection were mediated by the L6-S1 ventral roots, The best sphincteric response and intracavernous pressure rise were obtained by stimulation of the L6 ventral root, and the highest bladder pressures by stimulation of the 8 1 ventral root, Stimulation of the S1-S2 ventral roots provoked ipsilateral tail movement; of L6, tail movement, hindleg muscle twitch, and slight toe spread; and of Ls, hindleg stretch and plantar flexion, No significant differences were found between the two strains of rats, although a higher bladder pressure was recorded during stimulation of the L6 ventral root in Sprague-Dawley rats, which might be explained by a small caudal shift of the sacral parasympathetic nucleus in the Wistar strain,
Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction ... more Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction (VOD). From 2012 to 2016, refractory impotence prompted four men to seek further treatment, although they underwent six CEs elsewhere. Uncontrolled coils scattered along penile drainage veins including the deep dorsal veins (n = 3), periprostatic plexus (n = 1), iliac vein (n = 1), right pulmonary artery (n = 2), left pulmonary artery (n = 1), and right ventricle (n = 1). The last one occurred in a 40-year-old house builder, and the coil perforated the right ventricle wall and diaphragm 18 months later. Given no sustainable improvement, CE's safety and efficacy are unreliable for treating patients with VOD.
Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An ... more Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An obstructive aetiology is found in approximately 40% of azoospermic men. Of these, 30–67% have obstruction at the level of the epididymis. Th is study looks at the outcome of microsurgical epididymovasostomy in the management of obstructive azoospermia, specifi cally the patency and pregnancy rates aft er reconstruction. Patients and Methods: Th e outcome of the microsurgical epididymovasostomy procedures performed between 2000–2011 was retrospectively analysed. Azoospermic patients with normal testicular size, with or without epididymal dilatation, with a normal hormone profi le (FSH, LH, and Testosterone), normal male reproductive genetic profi le (XY), and a TRUS showing no evidence of ejaculatory duct obstruction, underwent scrotal exploration. An intraoperative vasogram was performed to exclude distal obstruction. Scrotal exploration was performed in 124 patients. Th e abscence of di...
Objective To investigate whether changes in the structure of the tunica albuginea influence the ... more Objective To investigate whether changes in the structure of the tunica albuginea influence the development of erectile dysfunction. Patients and methods Biopsy specimens taken from the tunica of 64 patients (both potent and impotent) with and without Peyronie's disease were evaluated. Tissue samples were stained and examined under light and electron microscopy, and the concentration of elastic fibres present in each was measured using computerized image analysis. Results The concentration of elastic fibres was lower in impotent than in potent patients (P=0.0365) and was also significantly less in patients with Peyronie's disease. Furthermore, the concentration of elastic fibres decreased with age. Electron and light microscopy revealed the presence of distinct alterations in the tunica albuginea in impotent patients and patients with Peyronie's disease that might interfere with function. Conclusion The decrease in elastic fibre concentration and changes in microscop...
We describe our experience with plaque excision and placement of a venous patch graft. Sprague Da... more We describe our experience with plaque excision and placement of a venous patch graft. Sprague Dawley rats (n = 20) underwent excision of a wedge of tunica albuginea with the defect covered by a segment of detubularized femoral vein, endothelial side towards the cavernous tissue. Erectile function, as determined by the rise in intracavernous pressure with cavernous nerve stimulation (mean 54.0 ± 4.2 cm. H 2 0), was equal to that in a group of 10 intact age-matched controls (mean 46.9 ± 3.37 cm. H 2 0). Penile cross-sections stained with Hart's elastic fiber stain or Trichrome stain revealed only minimal fibrosis in the region of the patch. In 3 dogs, a wedge of tunica was removed, and the defect was covered with a segment of detubularized deep dorsal vein. When sacrificed at 3 months, all animals had retained their erectile function with histologic evidence of minimal fibrosis. On the basis of histologic and functional data, the venous patch appears to be a reasonable alternative substance to those in common use.
Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance me... more Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance mediates nonadrenergic, noncholinergic relaxation of trabecular smooth muscle through activation of the cyclic guanosine monophosphate (cGMP) pathway. In 60 Sprague-Dawley rats, we investigated the effect of intracavernous administration of different drugs known to act at different levels of the cyclic adenosine monophosphate (cAMP) and cGMP pathways. Neither cAMP nor drugs that stimulate adenylate cyclase activity (vasoactive intestinal peptide, prostaglandin E1, calcitonin gene-related peptide) provoked any change in the basal intracavernous pressure. N-ethylmaleimide, an inhibitor of the enzyme adenylate cyclase, did not modify the response to electrostimulation of the cavernous nerve, indicating that the cAMP pathway does not play a significant role in penile erection in rats. However, intracavernous administration of methylene blue, a guanylate cyclase inhibitor, significantly reduced the response to electrostimulation (p = 0.001). Direct intracavernous injection of cGMP caused a statistically significant, dose-dependent increase in intravenous pressure that was not significantly inhibited by methylene blue. Sodium nitroprusside, a nitric oxide releaser and therefore a guanylate cyclase activator, caused a dose-dependent increase in intracavernous pressure (p < 0.05) that was inhibited almost completely by methylene blue (p = 0.002), supporting the theory that nitric oxide activates the synthesis of cGMP and that cGMP causes cavernous smooth muscle relaxation. Papaverine elicited an intracavernous pressure increase that was not affected by methylene blue or N-ethylmaleimide, indicating that papaverine acts through an independent pathway.(ABSTRACT TRUNCATED AT 250 WORDS)
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