madman
Super Moderator
INTRODUCTION
Michal and colleagues1 reported the first penile microvascular artery bypass surgery (MABS) for erectile dysfunction (ED) in 1973. He and his collaborators directly anastomosed the inferior epigastric artery (IEA) to the corpus cavernosum (Michal I), which resulted in intraoperative erections and excellent flow rates (>100 mL/min). This approach was also associated with close to 100% anastomotic stenosis/thrombosis, and thus the results were not durable. Subsequently, Michal’s team anastomosed the IEA with the dorsal penile artery using an end-to-side anastomosis technique in an attempt to improve patency rates. The documented success rate using nonvalidated instruments of this Michal II procedure was 56%.2
Eight years later, Virag and colleagues3 reported 92 cases with 54 MABS using an IEA to deep dorsal vein technique. The goal was to increase penile perfusion in a retrograde fashion. The reported success rate was 49% with an additional 20% of men reporting improvement in ED.3 This artery to-vein technique unfortunately also resulted in glans hyperemia in most patients, which was minimized by ligation of the circumflex branches. Furlow and Fisher4 reported a 62% success rate using an artery-to-vein technique with ligation of the circumflex branches. Hauri5 continued to modify the penile arterial bypass technique by performing a complicated side-to-side anastomosis between the dorsal artery (DA) and vein covered by a spatulated IEA in an attempt to improve outcomes and satisfaction rates.
In the modern era, penile revascularization procedures are rarely performed for a variety of reasons, the principal among them being the availability of safe and efficacious oral therapy for ED. However, in select young, healthy men with vasculogenic ED secondary to arterial insufficiency, MABS has the potential to reverse the pathophysiology of ED and restore normal erectile function.
*Venous vascular surgery was a common procedure for ED in the 1980s and 1990s. Current guidelines on ED recommend against these procedures owing to poor long-term surgical outcomes. In select patients, venous ligation surgery by an experienced surgeon may be an option.6
*MICROARTERIAL BYPASS SURGERY
Ideal Surgical Candidate
Patient selection is crucial for optimal outcomes after vascular interventions for ED. In general, young healthy men with focal vascular disease are thought to benefit the most from vascular surgery. In the 2015 International Consultation on Sexual Medicine Report, the authors recommend considering vascular interventions for men younger than 55 years old, with “recently acquired ED from focal arterial occlusive disease in the absence of other risk factors.”7 Although exact criteria have not been agreed upon, we have expanded the patient criteria based on the limited available literature and our institutional experience.7–10
1. Age: Trost and colleagues 7 reported that age less than 55 may be a predictor of better outcomes, but also that “data was insufficient to define a specific cut-off point” (Evidence Grade C). However, we believe the ideal candidate should be less than 50 years of age or even younger (<40 years old).
2. Absence of vascular risk factors (diabetes, hypertension, tobacco use, hypercholesterolemia, etc).
3. Absence of neurologic ED (eg, multiple sclerosis, pelvic surgery, lumbosacral radiculopathies).
4. Absence of untreated hormonal abnormalities.
5. Absence of active or significant psychiatric disorders (severe depression, bipolar disease, or schizophrenia) or the use of psychotropic drugs owing to their documented sexual side effects.
6. Absence of Peyronie’s disease.
7. Absence of untreated premature ejaculation.
8. Absence of acute or chronic perineal or pelvic trauma.
9. Absence of corporo-occlusive dysfunction by duplex Doppler ultrasound examination and cavernosometry.
10. Focal occlusive disease of the common penile or cavernosal arteries documented by penile duplex Doppler ultrasound examination with or without cavernosometry and confirmed by selective internal pudendal arteriography.
*Vascular Anatomy
*Hemodynamic Evaluation
-Penile duplex Doppler ultrasound examination and dynamic infusion cavernosometry
-Selective internal pudendal arteriography
*Surgical Technique
-Dorsal artery dissection
-Harvesting of the inferior epigastric artery
-Inferior epigastric artery transfer
-Microvascular anastomosis
*VENOUS VASCULAR SURGERY
The 2018 American Urological Association guideline on ED states that “for men with ED, penile venous surgery is not recommended.” This recommendation is derived from poor long-term surgical outcomes.8 However, in select cases, venous ligation surgery may be beneficial.
Ideal Surgical Candidate
1. Normal cavernous arteries on color duplex Doppler studies and/or cavernosometry. However, there are no definitive data.10
2. Abnormal, but limited veno-occlusion dysfunction demonstrated by penile Duplex Doppler ultrasound examination and/or cavernosometry.
3. Localization of the site of venous leakage on pharmacocavernosography to a discrete area of the corporal crura.
4. No medical contraindication to surgery.
5. No vascular risk factors.
6. Highly motivated patient who understands that venous ligation surgery has poor long-term outcomes, but may be effective in select cases.
*Surgical Technique
-Positioning and surgical approach
-Venous vascular ligation
DISCUSSION
*MABS Surgical Outcomes
*Microvascular Artery Bypass Surgery Complications
*Venous vascular surgery outcomes
*Venous vascular surgery complications
*LIMITATIONS IN STUDIES OF VASCULAR INTERVENTIONS
SUMMARY
The current treatment of ED is aimed at managing the condition but none of the current treatments approved by the US Food and Drug Administration can cure or reverse the pathophysiology of vasculogenic ED. Penile MABS may be the only treatment capable of restoring erectile function without the need for the chronic use of vasoactive medications or placement of a penile prosthesis. Similarly, in select cases, penile venous ligation surgery may be beneficial. However, current guidelines do not support penile venous surgery. The lack of standardization in patient selection, hemodynamic evaluation, surgical technique, and limited long-term outcome data using validated instruments has resulted in these surgeries being considered experimental and rarely performed.
Michal and colleagues1 reported the first penile microvascular artery bypass surgery (MABS) for erectile dysfunction (ED) in 1973. He and his collaborators directly anastomosed the inferior epigastric artery (IEA) to the corpus cavernosum (Michal I), which resulted in intraoperative erections and excellent flow rates (>100 mL/min). This approach was also associated with close to 100% anastomotic stenosis/thrombosis, and thus the results were not durable. Subsequently, Michal’s team anastomosed the IEA with the dorsal penile artery using an end-to-side anastomosis technique in an attempt to improve patency rates. The documented success rate using nonvalidated instruments of this Michal II procedure was 56%.2
Eight years later, Virag and colleagues3 reported 92 cases with 54 MABS using an IEA to deep dorsal vein technique. The goal was to increase penile perfusion in a retrograde fashion. The reported success rate was 49% with an additional 20% of men reporting improvement in ED.3 This artery to-vein technique unfortunately also resulted in glans hyperemia in most patients, which was minimized by ligation of the circumflex branches. Furlow and Fisher4 reported a 62% success rate using an artery-to-vein technique with ligation of the circumflex branches. Hauri5 continued to modify the penile arterial bypass technique by performing a complicated side-to-side anastomosis between the dorsal artery (DA) and vein covered by a spatulated IEA in an attempt to improve outcomes and satisfaction rates.
In the modern era, penile revascularization procedures are rarely performed for a variety of reasons, the principal among them being the availability of safe and efficacious oral therapy for ED. However, in select young, healthy men with vasculogenic ED secondary to arterial insufficiency, MABS has the potential to reverse the pathophysiology of ED and restore normal erectile function.
*Venous vascular surgery was a common procedure for ED in the 1980s and 1990s. Current guidelines on ED recommend against these procedures owing to poor long-term surgical outcomes. In select patients, venous ligation surgery by an experienced surgeon may be an option.6
*MICROARTERIAL BYPASS SURGERY
Ideal Surgical Candidate
Patient selection is crucial for optimal outcomes after vascular interventions for ED. In general, young healthy men with focal vascular disease are thought to benefit the most from vascular surgery. In the 2015 International Consultation on Sexual Medicine Report, the authors recommend considering vascular interventions for men younger than 55 years old, with “recently acquired ED from focal arterial occlusive disease in the absence of other risk factors.”7 Although exact criteria have not been agreed upon, we have expanded the patient criteria based on the limited available literature and our institutional experience.7–10
1. Age: Trost and colleagues 7 reported that age less than 55 may be a predictor of better outcomes, but also that “data was insufficient to define a specific cut-off point” (Evidence Grade C). However, we believe the ideal candidate should be less than 50 years of age or even younger (<40 years old).
2. Absence of vascular risk factors (diabetes, hypertension, tobacco use, hypercholesterolemia, etc).
3. Absence of neurologic ED (eg, multiple sclerosis, pelvic surgery, lumbosacral radiculopathies).
4. Absence of untreated hormonal abnormalities.
5. Absence of active or significant psychiatric disorders (severe depression, bipolar disease, or schizophrenia) or the use of psychotropic drugs owing to their documented sexual side effects.
6. Absence of Peyronie’s disease.
7. Absence of untreated premature ejaculation.
8. Absence of acute or chronic perineal or pelvic trauma.
9. Absence of corporo-occlusive dysfunction by duplex Doppler ultrasound examination and cavernosometry.
10. Focal occlusive disease of the common penile or cavernosal arteries documented by penile duplex Doppler ultrasound examination with or without cavernosometry and confirmed by selective internal pudendal arteriography.
*Vascular Anatomy
*Hemodynamic Evaluation
-Penile duplex Doppler ultrasound examination and dynamic infusion cavernosometry
-Selective internal pudendal arteriography
*Surgical Technique
-Dorsal artery dissection
-Harvesting of the inferior epigastric artery
-Inferior epigastric artery transfer
-Microvascular anastomosis
*VENOUS VASCULAR SURGERY
The 2018 American Urological Association guideline on ED states that “for men with ED, penile venous surgery is not recommended.” This recommendation is derived from poor long-term surgical outcomes.8 However, in select cases, venous ligation surgery may be beneficial.
Ideal Surgical Candidate
1. Normal cavernous arteries on color duplex Doppler studies and/or cavernosometry. However, there are no definitive data.10
2. Abnormal, but limited veno-occlusion dysfunction demonstrated by penile Duplex Doppler ultrasound examination and/or cavernosometry.
3. Localization of the site of venous leakage on pharmacocavernosography to a discrete area of the corporal crura.
4. No medical contraindication to surgery.
5. No vascular risk factors.
6. Highly motivated patient who understands that venous ligation surgery has poor long-term outcomes, but may be effective in select cases.
*Surgical Technique
-Positioning and surgical approach
-Venous vascular ligation
DISCUSSION
*MABS Surgical Outcomes
*Microvascular Artery Bypass Surgery Complications
*Venous vascular surgery outcomes
*Venous vascular surgery complications
*LIMITATIONS IN STUDIES OF VASCULAR INTERVENTIONS
SUMMARY
The current treatment of ED is aimed at managing the condition but none of the current treatments approved by the US Food and Drug Administration can cure or reverse the pathophysiology of vasculogenic ED. Penile MABS may be the only treatment capable of restoring erectile function without the need for the chronic use of vasoactive medications or placement of a penile prosthesis. Similarly, in select cases, penile venous ligation surgery may be beneficial. However, current guidelines do not support penile venous surgery. The lack of standardization in patient selection, hemodynamic evaluation, surgical technique, and limited long-term outcome data using validated instruments has resulted in these surgeries being considered experimental and rarely performed.
