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Wayne J G Hellstrom - One of the best experts on this subject based on the ideXlab platform.

  • The effect of vascular risk factors on Penile vascular status in men with erectile dysfunction.
    The Journal of Urology, 2007
    Co-Authors: Muammer Kendirci, Landon Trost, Suresh C. Sikka, Wayne J G Hellstrom
    Abstract:

    Purpose: The cause of erectile dysfunction is mostly organic in nature and is most commonly associated with a vasculogenic etiology. This study evaluates the relationship between Penile hemodynamic parameters and vascular risk factors in men with erectile dysfunction.Materials and Methods: A total of 1,216 patients with erectile dysfunction were evaluated regarding the relationship between vascular risk factors and Penile vascular parameters. The patients were stratified according to the type and number of risk factors present. Each patient underwent a Penile duplex Doppler ultrasound study after injections of intracavernous prostaglandin E1 with accompanying visual sexual stimulation to evaluate Penile Blood Flow parameters. Specific criteria were used to categorize patients according to varying definitions of vascular status. The odds ratio for selected vascular risk factors was calculated. The rates of arterial insufficiency, venoocclusive dysfunction, mixed vascular disease and nonvascular etiologies ...

  • Diabetes mellitus is associated with severe Peyronie's disease.
    BJUI, 2007
    Co-Authors: Muammer Kendirci, Landon Trost, Suresh C. Sikka, Wayne J G Hellstrom
    Abstract:

    OBJECTIVES To evaluate the severity of Penile deformity and Penile Blood Flow variables in men with Peyronie’s disease (PD) and diabetes mellitus (DM), and those with no risk factors. PATIENTS AND METHODS Men with PD and DM (59 men, group 1) and those with no risk factors (109, group 2) were compared for Penile Blood Flow variables, severity of Penile deformity, patient’s age, duration of PD, the presence of pain on erection, and the degree of erectile dysfunction (ED). The men were evaluated with Penile duplex Doppler ultrasonography and were categorized into specific vascular groups, using established criteria. Penile curvature was objectively measured and stratified according to the Kelâmi classification. Results were compared using Student’s t-test. RESULTS Men with PD and DM (group 1) were significantly older than those in group 2. The duration of disease was significantly longer in group 1 than in group 2 (median 24 vs 12 months). The mean degree of Penile deformity in group 1 was significantly higher than in group 2 (45.2° vs 30.2°). The rate of severe Penile curvature (>60°) was more frequent in group 1 (27.1% vs 5.5%). Pain on erection was significantly higher in group 2 (39.7% vs 25.5%), whereas the rate of ED was more common in group 1 (81% vs 47%). Group 1 had poorer peak-systolic velocity values and significantly higher rates of arterial insufficiency and mixed vascular disease. Nonvascular causes were twice as common in group 2 than in group 1. CONCLUSIONS This comparative clinical study suggests that the presence of DM as the only risk factor significantly increases the severity of PD. Furthermore, DM as a risk factor is associated with significantly worse vascular status, as shown by Penile duplex Doppler ultrasonography, in men with PD.

  • THE RELATIONSHIP BETWEEN THE TYPE OF Penile ABNORMALITY AND Penile VASCULAR STATUS IN PATIENTS WITH PEYRONIE'S DISEASE
    The Journal of Urology, 2005
    Co-Authors: Muammer Kendirci, Suresh C. Sikka, Sepehr Nowfar, George W. Jabren, Wayne J G Hellstrom
    Abstract:

    ABSTRACTPurpose: We evaluated Penile vascular status using Penile duplex Doppler ultrasound (PDDU) according to the type of abnormality in men with Peyronie's disease (PD).Materials and Methods: A total of 523 patients with PD were evaluated retrospectively. Each patient underwent PDDU following injections of 10 to 15 μg prostaglandin E1 intracavernously with accompanying visual sexual stimulation to evaluate Penile Blood Flow. Abnormalities were divided into 7 groups. Objective evaluation of Penile curvature was done with a protractor during maximum erection. Specific criteria were used to categorize patients into varying definitions of vascular status. The results were compared statistically among groups.Results: Mean patient age ± SEM was 54.2 ± 1.5 years. The most frequently noted type of curvature was dorsal (43.5% of cases), followed by lateral (24.8%). Mean peak systolic velocity in the ventrolateral group was the highest, while the lowest peak systolic velocity was noted in the hourglass abnormali...

  • Peyronie’s disease: Advances in basic science and pathophysiology
    Current Urology Reports, 2000
    Co-Authors: Trinity J Bivalacqua, Sunil K. Purohit, Wayne J G Hellstrom
    Abstract:

    Peyronie’s disease is an idiopathic, localized connective tissue disorder of the penis that involves the tunica albuginea of the corpus cavernosum and the adjacent areolar space. The tunica albuginea plays an important role in the mechanism of erection. Peyronie’s disease is characterized by local changes in the collagen and elastic fiber composition of the tunica albuginea. The formation of fibrotic plaques alters Penile anatomy and can cause different degrees of bending, narrowing, or shortening of the penis. Moreover, a significant number of men with Peyronie’s disease develop erectile dysfunction. Penile Blood Flow studies in many patients with Peyronie’s disease suggest a strong association with veno-occlusive dysfunction. Although long recognized as an important clinical entity of the male genitalia, the etiology of this disease has remained poorly understood. The following review focuses on recent research on the pathophysiology of Peyronie’s disease.

  • no effect on Penile Blood Flow and lower genitourinary tract function
    2000
    Co-Authors: Trinity J Bivalacqua, Hunter C Champion, Philip J Kadowitz, Wayne J G Hellstrom
    Abstract:

    Nitric oxide (NO) is an unstable radical that exists primarily as a gas. For decades, NO was thought to be an environmental contaminant. Highly toxic, it was considered an unlikely candidate as a biological mediator. However, a landmark article by Furchgott and Zawadzki in 1980 described the release of a substance by the endothelial lining of Blood vessels that was responsible for the vasorelaxation of smooth muscle in response to acetylcholine. They named this novel molecule endothelium-derived relaxing factor (EDRF). Since that time, most authorities have concluded that EDRF is NO (Ignarro et al. 1987; Palmer et al. 1987), however some researchers postulate that EDRF is actually an S-nitrosothiol that acts through NO transfer (Meyers et a1. 1990).

Suresh C. Sikka - One of the best experts on this subject based on the ideXlab platform.

  • The effect of vascular risk factors on Penile vascular status in men with erectile dysfunction.
    The Journal of Urology, 2007
    Co-Authors: Muammer Kendirci, Landon Trost, Suresh C. Sikka, Wayne J G Hellstrom
    Abstract:

    Purpose: The cause of erectile dysfunction is mostly organic in nature and is most commonly associated with a vasculogenic etiology. This study evaluates the relationship between Penile hemodynamic parameters and vascular risk factors in men with erectile dysfunction.Materials and Methods: A total of 1,216 patients with erectile dysfunction were evaluated regarding the relationship between vascular risk factors and Penile vascular parameters. The patients were stratified according to the type and number of risk factors present. Each patient underwent a Penile duplex Doppler ultrasound study after injections of intracavernous prostaglandin E1 with accompanying visual sexual stimulation to evaluate Penile Blood Flow parameters. Specific criteria were used to categorize patients according to varying definitions of vascular status. The odds ratio for selected vascular risk factors was calculated. The rates of arterial insufficiency, venoocclusive dysfunction, mixed vascular disease and nonvascular etiologies ...

  • Diabetes mellitus is associated with severe Peyronie's disease.
    BJUI, 2007
    Co-Authors: Muammer Kendirci, Landon Trost, Suresh C. Sikka, Wayne J G Hellstrom
    Abstract:

    OBJECTIVES To evaluate the severity of Penile deformity and Penile Blood Flow variables in men with Peyronie’s disease (PD) and diabetes mellitus (DM), and those with no risk factors. PATIENTS AND METHODS Men with PD and DM (59 men, group 1) and those with no risk factors (109, group 2) were compared for Penile Blood Flow variables, severity of Penile deformity, patient’s age, duration of PD, the presence of pain on erection, and the degree of erectile dysfunction (ED). The men were evaluated with Penile duplex Doppler ultrasonography and were categorized into specific vascular groups, using established criteria. Penile curvature was objectively measured and stratified according to the Kelâmi classification. Results were compared using Student’s t-test. RESULTS Men with PD and DM (group 1) were significantly older than those in group 2. The duration of disease was significantly longer in group 1 than in group 2 (median 24 vs 12 months). The mean degree of Penile deformity in group 1 was significantly higher than in group 2 (45.2° vs 30.2°). The rate of severe Penile curvature (>60°) was more frequent in group 1 (27.1% vs 5.5%). Pain on erection was significantly higher in group 2 (39.7% vs 25.5%), whereas the rate of ED was more common in group 1 (81% vs 47%). Group 1 had poorer peak-systolic velocity values and significantly higher rates of arterial insufficiency and mixed vascular disease. Nonvascular causes were twice as common in group 2 than in group 1. CONCLUSIONS This comparative clinical study suggests that the presence of DM as the only risk factor significantly increases the severity of PD. Furthermore, DM as a risk factor is associated with significantly worse vascular status, as shown by Penile duplex Doppler ultrasonography, in men with PD.

  • THE RELATIONSHIP BETWEEN THE TYPE OF Penile ABNORMALITY AND Penile VASCULAR STATUS IN PATIENTS WITH PEYRONIE'S DISEASE
    The Journal of Urology, 2005
    Co-Authors: Muammer Kendirci, Suresh C. Sikka, Sepehr Nowfar, George W. Jabren, Wayne J G Hellstrom
    Abstract:

    ABSTRACTPurpose: We evaluated Penile vascular status using Penile duplex Doppler ultrasound (PDDU) according to the type of abnormality in men with Peyronie's disease (PD).Materials and Methods: A total of 523 patients with PD were evaluated retrospectively. Each patient underwent PDDU following injections of 10 to 15 μg prostaglandin E1 intracavernously with accompanying visual sexual stimulation to evaluate Penile Blood Flow. Abnormalities were divided into 7 groups. Objective evaluation of Penile curvature was done with a protractor during maximum erection. Specific criteria were used to categorize patients into varying definitions of vascular status. The results were compared statistically among groups.Results: Mean patient age ± SEM was 54.2 ± 1.5 years. The most frequently noted type of curvature was dorsal (43.5% of cases), followed by lateral (24.8%). Mean peak systolic velocity in the ventrolateral group was the highest, while the lowest peak systolic velocity was noted in the hourglass abnormali...

  • standardization of Penile Blood Flow parameters in normal men using intracavernous prostaglandin e1 and visual sexual stimulation
    The Journal of Urology, 1993
    Co-Authors: Suresh C. Sikka, Eduardo Randrup, Peggy Villemarette, Neil Baum, John F Hower, Wayne J G Hellstrom
    Abstract:

    AbstractThe evaluation of vasculogenic impotence by color Flow Doppler ultrasound after injection of intracavernous vasoactive agents allows for simultaneous visualization in real time of arterial and venous Blood Flow. Normal arterial Blood Flow parameters after prostaglandin E1 injection have yet to be standardized. Our study was initiated to evaluate Blood Flow parameters in a normal control population after prostaglandin E1 and visual stimulation.A total of 20 healthy male volunteers 45 to 60 years old with histories of normal sexual function was selected. All volunteers were given intracavernous injections of 10 μg. prostaglandin E1 and received concurrent visual stimulation by means of an erotic video. All patients developed rigid erections with no complications. Using color Flow Doppler ultrasound measurements were done before and after prostaglandin E1 injection of right and left superficial and deep cavernous artery diameters, peak Blood Flow velocities and Blood Flow volumes.Results (mean plus o...

Elroy D Kursh - One of the best experts on this subject based on the ideXlab platform.

  • a dynamic dual isotope radionuclear method of quantifying Penile Blood Flow
    The Journal of Urology, 1992
    Co-Authors: Elroy D Kursh, Terry W Jones, Samuel Thompson, Dennis Nelson, Floro Miraldi
    Abstract:

    AbstractA new radionuclear method of quantifying arterial and venous Blood Flow of the penis is described. The technique is based on the simultaneous recording of the change in Blood volume and venous outFlow in the flaccid and erect states, which is produced pharmacologically. The change in Penile Blood volume is determined by measuring the change in the technetium-labeled red Blood cell activity with time. Venous outFlow is recorded with a xenon washout technique. The isotope data are used to compute arterial and venous Flows with a complex computerized mathematical formula. Three basic Blood Flow patterns have been noted that distinguish normal patients from those with arterial insufficiency and venous leakage. The study is relatively easy and noninvasive to perform, and it appears to quantify Penile Blood Flow accurately.

  • a dual radioisotope technique for the evaluation of Penile Blood Flow during tumescence
    The Journal of Nuclear Medicine, 1992
    Co-Authors: Floro Miraldi, Samuel Thompson, A D Nelson, W T Jones, Elroy D Kursh
    Abstract:

    : A technique is described for concomitant study of both arterial and venous Penile Blood Flow during tumescence. Dual-isotope acquisition is started after labeling red cells in vivo with 99mTc. Xenon-133 in saline is then injected into the corpus cavernosum followed with vasoactive drugs to induce an erection. The resulting xenon and technetium time-activity curves are inputs for a one-compartment model. In 14 subjects, the average peak arterial Flow rate (PAF) for normal males was calculated as 13.0 +/- 1.28 ml/min (avg +/- s.d.) compared to 16.1 +/- 5.14 and 5.02 +/- 1.78 ml/min for patients with venous leak (VL) or arterial insufficiency (AI), respectively. Peak venous Flows (PVF) were 4.25 +/- 1.17, 12.1 +/- 3.75, and 3.78 +/- 1.00 ml/min for normal, VL and AL respectively. Al patients have significantly lower PAF than normal (p = 0.002) or VL patients (p = 0.018), and VL patients had significantly higher PVF than normal (p = 0.012) or Al (p = 0.018). The technique may be helpful in the study of impotence.

Floro Miraldi - One of the best experts on this subject based on the ideXlab platform.

  • a dynamic dual isotope radionuclear method of quantifying Penile Blood Flow
    The Journal of Urology, 1992
    Co-Authors: Elroy D Kursh, Terry W Jones, Samuel Thompson, Dennis Nelson, Floro Miraldi
    Abstract:

    AbstractA new radionuclear method of quantifying arterial and venous Blood Flow of the penis is described. The technique is based on the simultaneous recording of the change in Blood volume and venous outFlow in the flaccid and erect states, which is produced pharmacologically. The change in Penile Blood volume is determined by measuring the change in the technetium-labeled red Blood cell activity with time. Venous outFlow is recorded with a xenon washout technique. The isotope data are used to compute arterial and venous Flows with a complex computerized mathematical formula. Three basic Blood Flow patterns have been noted that distinguish normal patients from those with arterial insufficiency and venous leakage. The study is relatively easy and noninvasive to perform, and it appears to quantify Penile Blood Flow accurately.

  • a dual radioisotope technique for the evaluation of Penile Blood Flow during tumescence
    The Journal of Nuclear Medicine, 1992
    Co-Authors: Floro Miraldi, Samuel Thompson, A D Nelson, W T Jones, Elroy D Kursh
    Abstract:

    : A technique is described for concomitant study of both arterial and venous Penile Blood Flow during tumescence. Dual-isotope acquisition is started after labeling red cells in vivo with 99mTc. Xenon-133 in saline is then injected into the corpus cavernosum followed with vasoactive drugs to induce an erection. The resulting xenon and technetium time-activity curves are inputs for a one-compartment model. In 14 subjects, the average peak arterial Flow rate (PAF) for normal males was calculated as 13.0 +/- 1.28 ml/min (avg +/- s.d.) compared to 16.1 +/- 5.14 and 5.02 +/- 1.78 ml/min for patients with venous leak (VL) or arterial insufficiency (AI), respectively. Peak venous Flows (PVF) were 4.25 +/- 1.17, 12.1 +/- 3.75, and 3.78 +/- 1.00 ml/min for normal, VL and AL respectively. Al patients have significantly lower PAF than normal (p = 0.002) or VL patients (p = 0.018), and VL patients had significantly higher PVF than normal (p = 0.012) or Al (p = 0.018). The technique may be helpful in the study of impotence.

Mehdi H. Shishehbor - One of the best experts on this subject based on the ideXlab platform.

  • Current State of Endovascular Treatment for Vasculogenic Erectile Dysfunction
    Current Cardiology Reports, 2013
    Co-Authors: Femi Philip, Mehdi H. Shishehbor
    Abstract:

    Normal erectile function requires adequate Penile arterial inFlow, normal Penile architecture and an intact venous capacitance system. Vascular disease is the dominant etiology of erectile dysfunction (ED) and current medical therapy increases Penile Blood Flow. However, in a large proportion of patients, medical therapy is inadequate or contraindicated requiring the use of mechanical constrictive devices or implantation of a Penile prosthesis. Rapid advances in endovascular intervention have allowed safe and effective treatment of small arteries in other vascular beds. A minimally invasive approach targeting Penile arterial inFlow disease may prove to be safe and effective. In this paper, we discuss the normal arterial Blood supply to the penis, describe angiographic findings in patients with ED, and critically review the published data on endovascular and microsurgical approaches at reestablishing Penile Blood Flow. Lastly, we offer a potential algorithm and procedural tips for endovascular intervention for ED.