madman
Super Moderator
INTRODUCTION
Ultrasonography (US) is the primary imaging modality used for patients with penile conditions such as erectile dysfunction (ED), Peyronie’s disease (PD), penile trauma, and priapism. While patients are typically given a preliminary diagnosis based on history and physical examination, imaging is often required to confirm the diagnosis or to assess the extent of the condition. Ultrasound and magnetic resonance imaging are mostly used, but other techniques such as retrograde urethrography and computed tomography are performed in indicated cases. Currently, penile duplex Doppler ultrasonography (PDDU) is the gold standard for evaluating the etiology of ED based on hemodynamic parameters. Alternatively, standard grayscale US imaging is used to scan for non-vascular abnormalities such as fibrosis, plaques, or tunica albuginea (TA) defects.
Penile fibrosis, particularly the formation of plaques of the TA in patients with PD, has been well-studied1 ; however, the fibrosis of the corpora cavernosa is a highly prevalent sequela of various etiologies. Corporal fibrosis results from the loss of smooth muscle cells and the increase of collagen deposition. In fact, the composition of cavernosal tissue changes physiologically with age. In men between ages 41 and 60 years old, the abundance of smooth muscle cells reduces to 40% and reduces to about 35% in men over 60.2
Cases of penile corporal fibrosis may occur secondary to the explantation of an infected penile prosthesis, severe penile trauma, refractory low-flow priapism, PD, or chronic intra-cavernous injection of vasoactive drugs.3−8 Other etiologies of penile corporal fibrosis, presenting primarily with ED, can develop in chronic smokers, hypertensive patients, alcoholics, diabetics, and after radical prostatectomy.1,9,10 Corporal erectile tissue fibrosis is a significant pathophysiologic component of ED; however, current US-based penile imaging protocols do not directly assess it.
In this article, we review the literature to determine if grayscale US is a suitable imaging modality to identify and assess penile corporal erectile tissue fibrosis.
*Examination Technique
*Normal Anatomy
*Inflatable Penile Prosthesis
*Ischemic Priapism
*Penile Trauma
*Intracavernosal Injections
*Diabetes
*Peyronie’s Disease
*Vascular Disease
Discussion
We encourage providers to spend extra time to perform grayscale US, which can potentially identify and localize penile fibrosis and provide prognostic value. US should not be used to solely assess penile hemodynamics to assess ED but should also aim to capture tissue heterogeneity. In addition, grayscale US can provide an additional metric of tracking pre-and post-treatment fibrotic changes.
While grayscale US may become a valuable tool to assess corporal fibrosis, one limitation is the individual expertise required to perform and analyze US findings, a summary of which is provided in Table 1. Recognition of subtle sonographic changes is highly subjective, and normal features may be misinterpreted as fibrosis. The ultrasonographer must be knowledgeable of penile anatomy and the changes that occur due to pathological conditions. This limitation is exemplified by the number of cases of corporal fibrosis surprisingly found during penile implant surgery.85 Data remains limited in the published literature about whether these intraoperative complications occur in the absence of positive US findings. However, this could be added as a limitation to the use of grayscale US for tracking pre-operative fibrosis, as the technique is considered operator-dependent and requires both technical skill and detailed sonographic knowledge of penile anatomy.
CONCLUSION
Overall, grayscale US may be a useful and convenient imaging modality to assess penile corporal fibrosis secondary to the explantation of an infected penile prosthesis, priapism, penile trauma, chronic intra-cavernous injection of vasoactive drugs, diabetes, PD, and vascular disease. While limited by the skill and knowledge of the US operator, the combined knowledge of pathophysiology and US may help clinicians identify and manage the underlying etiology of penile corporal fibrosis.
Ultrasonography (US) is the primary imaging modality used for patients with penile conditions such as erectile dysfunction (ED), Peyronie’s disease (PD), penile trauma, and priapism. While patients are typically given a preliminary diagnosis based on history and physical examination, imaging is often required to confirm the diagnosis or to assess the extent of the condition. Ultrasound and magnetic resonance imaging are mostly used, but other techniques such as retrograde urethrography and computed tomography are performed in indicated cases. Currently, penile duplex Doppler ultrasonography (PDDU) is the gold standard for evaluating the etiology of ED based on hemodynamic parameters. Alternatively, standard grayscale US imaging is used to scan for non-vascular abnormalities such as fibrosis, plaques, or tunica albuginea (TA) defects.
Penile fibrosis, particularly the formation of plaques of the TA in patients with PD, has been well-studied1 ; however, the fibrosis of the corpora cavernosa is a highly prevalent sequela of various etiologies. Corporal fibrosis results from the loss of smooth muscle cells and the increase of collagen deposition. In fact, the composition of cavernosal tissue changes physiologically with age. In men between ages 41 and 60 years old, the abundance of smooth muscle cells reduces to 40% and reduces to about 35% in men over 60.2
Cases of penile corporal fibrosis may occur secondary to the explantation of an infected penile prosthesis, severe penile trauma, refractory low-flow priapism, PD, or chronic intra-cavernous injection of vasoactive drugs.3−8 Other etiologies of penile corporal fibrosis, presenting primarily with ED, can develop in chronic smokers, hypertensive patients, alcoholics, diabetics, and after radical prostatectomy.1,9,10 Corporal erectile tissue fibrosis is a significant pathophysiologic component of ED; however, current US-based penile imaging protocols do not directly assess it.
In this article, we review the literature to determine if grayscale US is a suitable imaging modality to identify and assess penile corporal erectile tissue fibrosis.
*Examination Technique
*Normal Anatomy
*Inflatable Penile Prosthesis
*Ischemic Priapism
*Penile Trauma
*Intracavernosal Injections
*Diabetes
*Peyronie’s Disease
*Vascular Disease
Discussion
We encourage providers to spend extra time to perform grayscale US, which can potentially identify and localize penile fibrosis and provide prognostic value. US should not be used to solely assess penile hemodynamics to assess ED but should also aim to capture tissue heterogeneity. In addition, grayscale US can provide an additional metric of tracking pre-and post-treatment fibrotic changes.
While grayscale US may become a valuable tool to assess corporal fibrosis, one limitation is the individual expertise required to perform and analyze US findings, a summary of which is provided in Table 1. Recognition of subtle sonographic changes is highly subjective, and normal features may be misinterpreted as fibrosis. The ultrasonographer must be knowledgeable of penile anatomy and the changes that occur due to pathological conditions. This limitation is exemplified by the number of cases of corporal fibrosis surprisingly found during penile implant surgery.85 Data remains limited in the published literature about whether these intraoperative complications occur in the absence of positive US findings. However, this could be added as a limitation to the use of grayscale US for tracking pre-operative fibrosis, as the technique is considered operator-dependent and requires both technical skill and detailed sonographic knowledge of penile anatomy.
CONCLUSION
Overall, grayscale US may be a useful and convenient imaging modality to assess penile corporal fibrosis secondary to the explantation of an infected penile prosthesis, priapism, penile trauma, chronic intra-cavernous injection of vasoactive drugs, diabetes, PD, and vascular disease. While limited by the skill and knowledge of the US operator, the combined knowledge of pathophysiology and US may help clinicians identify and manage the underlying etiology of penile corporal fibrosis.
