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Comparison of Selective Internal Iliac Pharmaco- Angiography, Penile Brachial Index and Duplex Sonography with Pulsed Doppler Analysis for the Evaluation of Vasculogenic (Arteriogenic) Impotence
0022-534 7 /90 /1435-0928$02.00 /0 Vol. 143, May Printed in U.S.A.
THE JOURNAL OF UROLOGY Copyright© 1990 by AMERICAN UROLOGICAL ASSOCIATION, INC.
COMPARISON OF SELECTIVE INTERNAL ILIAC PHARMACOANGIOGRAPHY, PENILE BRACHIAL INDEX AND DUPLEX SONOGRAPHY WITH PULSED DOPPLER ANALYSIS FOR THE EVALUATION OF VASCULOGENIC (ARTERIOGENIC) IMPOTENCE STEFAN C. MUELLER, HUBERTUS v. WALLENBERG-PACHALY, GUNTHER E. VOGES HANS H. SCHILD
AND
From the Departments of Urology and Radiology, Mainz Medical School, Johannes Gutenberg University, Mainz, Federal Republic of Germany
ABSTRACT
Between July 1987 and February 1988 selective internal iliac angiography was performed before and after intracavernous injection of papaverine plus phentolamine in 43 patients with erectile dysfunction. In 63% of the patients stenosis or occlusion of the pudenda! artery was found. The penile brachial index was calculated and duplex sonography with pulsed Doppler analysis was performed in 23 patients. Angiography and penile brachial index correlated in only 39% of the patients, whereas selective internal iliac angiography and duplex sonography correlated in 91 % (21 of 23). In 2 patients duplex sonography with pulsed Doppler analysis rendered better information about penile arterial perfusion than did angiography. (J. Ural., 143: 928-932, 1990) Intracavernous injection of vasoactive drugs was first described by Virag in 1982, 1 and has revolutionized the diagnostic and therapeutic approach to the impotent patient. Erectile dysfunction most often is of organic origin and vascular problems represent the most frequent cause. 2 The penile brachial index, that is the penile systolic pressure divided by the brachial systolic pressure, is popular for noninvasive diagnosis of arteriogenic impotence. However, a normal penile brachial index does not necessarily rule out significant arterial lesions. 3 • 4 Blood pressure measurements usually are done on the flaccid penis with a continuous wave Doppler unit that detects all signals in its path. Therefore, most of the penile brachial index data probably derive from the dorsal arteries, since these have the highest flow in the flaccid state. However, these arteries primarily supply the glans penis and contribute little to the corpora cavernosa, which constitute the main structure for penile erection. Selective arteriography of the internal iliac artery was believed to be the method of choice to detect arterial lesions. 5 - 10 However, the technique is not standardized. Contrast media with lower osmolarity minimize the pain and allow the examination to be performed with the patient under local anesthesia.11 Spinal anesthesia might be preferable, since blockade of the sympathetic nervous system reduces vasospasms. Artificial erection is ideal to reduce the peripheral resistance and to allow dilation of the small penile vessels for better images. Because of the invasiveness of the method few men with normal potency have been investigated and, therefore, our knowledge of the so-called normal morphology of the penile arterial blood supply is limited. Duplex sonography and pulsed Doppler analysis before and after intracavernous injection of vasoactive drugs allow for sonographic visualization of the penile arteries and provide a limited invasive functional test for the evaluation of arteriogenic impotence. 2 • 12- 15 We compared these 3 diagnostic procedures (selective internal iliac pharmaco-angiography, penile brachial index and duplex sonography with pulsed Doppler analysis) concerning the diagnostic value in the evaluation of patients with erectile dysfunction. MATERIALS AND METHODS
Between July 1987 and February 1988, 43 men 32 to 77 years old underwent selective internal iliac pharmaco-arteriography Accepted for publication October 6, 1989. 928
for the evaluation of erectile impotence. In 23 patients calculation of the penile brachial index and duplex sonography with pulsed Doppler analysis were performed. The tests were done by separate investigators.
FIG. 1. Normal selective internal iliac pharmaco-angiography of left side in 56-year-old impotent patient. A, before intracavernous injection of papaverine plus phentolamine. Thick arrow indicates urethral bulb and thin arrow shows dorsal artery. B, after intracavernous injection of 1 cc mixture of papaverine (15 mg.fee) and phentolamine (0.5 mg./ cc) during tumescence phase. Thick arrow shows urethral bulb, thin arrow shows dorsal artery and double arrows indicate cavernous artery.
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FIG. 2. Duplex sonograms with pulsed Doppler analysis. During tumescence with arterial system intact initial diameter of cavernous artery should increase up to 2-fold and peak blood flow values should be at least 25 cm. per second. A, before intracavernous injection of papaverine plus phentolamine in flaccid penis arterial diameter is 0.4 mm. and maximum flow within cavernous artery is 7 cm. per second. B, after injection of 0.5 ml. mixture of papaverine and phentolamine during tumescence phase arterial diameter is 1.0 mm. and maximum flow within cavernous artery is 26 cm. per second.
FIG. 3. A, normal selective internal iliac pharmaco-angiography after intracavernous injection of 1 ml. papaverine plus phentolamine mixture. Thick arrow indicates urethral artery, thin arrow indicates dorsal artery and double arrows show cavernous artery. B, duplex sonography during tumescence phase after intracavernous injection of 0.5 ml. drug mixture shows reduced flow (10 cm. per second), obvious thickening of arterial wall and poor arterial pulsations in patient with poor erectile response.
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FIG. 4. Selective internal iliac pharmaco-angiography after intracavernous injection of 1 ml. mixture of papaverine and phentolamine. A, visualization of 2 cavernous arteries (double arrows) on left side. Large arrow indicates dorsal artery and asterisk shows scrotal branch. B, no visualization of cavernous artery on right side. Asterisk indicates scrotal branch.
Technique of selective penile pharmaco-angiography. After both femoral arteries are punctured 5F catheters are placed into the ipsilateral internal iliac arteries. Angiography examinations are performed on the flaccid penis and during the tumescence phase after intracavernous injection of 1 cc of a mixture of 15 mg. papaverine per cc and 0.5 mg. phentolamine per cc. The flow rate was 3.5 cc per second and the total amount was 60 cc per series. The initial exposure is made 8 seconds after starting the injection of the contrast medium. Before proper placement of the catheters into the internal iliac arteries pelvic angiography is performed to exclude stenoses in the larger vessels feeding the region of interest. In a flaccid penis the contracted smooth musculature produces a high peripheral resistance such that adequate filling of the small penile vessels cannot be achieved (fig. 1, A). After intracavernous injection of a smooth muscle relaxant those vessels should be visible and are believed to be normal as long as there are no obvious caliber changes or incomplete filling (fig.1,B). Technique of calculation of the penile brachia! index. With the patient in the prone position a pediatric blood pressure cuff is placed around the penis. The penile arteries then are auscultated distal to the cuff with an 8 MHz. bidirectional continuous wave Doppler unit and systolic blood pressure values are measured. Investigations are done on the flaccid penis. For calculation of the penile brachial index the penile systolic pressure is divided by the brachial systolic pressure. The established value of 0.7 was used to differentiate normal from abnormal penile arterial pressures and a value of less than 0.7 suggested vasculogenic impotence.4
FIG. 5. Although pharmaco-angiography suggested occlusion of penile arteries on right side, duplex sonography during tumescence phase after intracavernous injection of 0.5 ml. drug mixture shows normal flow (0.27 m. per second) and good arterial dilatation (O. 7 mm.) of right cavernous artery.
Technique of duplex sonography and pulsed Doppler analysis. This study is performed with a real-time 7.5 MHz. B-scanner and a 4.5 MHz. pulsed Doppler system, both transducers integrated in 1 probe. Initially, the diameters of the cavernous arteries are measured longitudinally and transversely. Echogenicity of the arterial wall and of the cavernous smooth muscle is recorded, as well as pulsation of the vessels along the entire length of the cavernous arteries. Finally, the blood flow is measured (cm. per second) in the individual arteries. After injection of 0.5 cc of a mixture of 15 mg. papaverine per cc plus 0.5 mg. phentolamine per cc the investigation is repeated during early tumescence. Experience with this technique shows that during tumescence, with the arterial system intact, the initial diameter of the cavernous artery should increase up to 2-fold (fig. 2) and the peak blood flow values should be at least 25 cm. per second. 13- 15 RESULTS
Selective internal iliac pharmaco-angiography was normal in 16 of the 43 patients (37% ), while in 27 (63%) it demonstrated occlusion or high grade stenosis of the pelvic vessels, cavernous arteries or pudendal artery. A total of 9 patients (39%) showed good correlation between angiography and penile brachial index. However, 7 of these 9 patients had a normal angiography and penile brachial index with our criteria, while in only 2 did the penile brachial index suggest arterial insufficiency that correlated with the angiographic morphology. In 14 patients
931
EVALUATION OF ARTERIOGENIC IMPOTENCE
responsible for the blood supply with a cross-over to the right cavernous artery. DISCUSSION
FIG. 6. Duplex sonography with pulsed Doppler analysis. With full erection and increasing rigidity cavernous tissue often will compress cavernous arteries and blood flow subsequently will decrease to minimum. Therefore, duplex study must be performed during tumescence to avoid false results. A, after intracavernous injection of papaverine plus phentolamine during early tumescence high flow can be measured within cavernous artery (maximum flow 38 cm. per second). B, 5 minutes after intracavernous injection of drug mixture normal erection has developed and because of increased cavernous pressure arterial flow within cavernous artery has diminished dramatically (maximum flow 19 cm. per second).
(61 %) angiography did not correlate with penile brachia! index. Duplex sonography with pulsed Doppler analysis and angiography showed a positive correlation in 21 patients (91 %), while in 2 (9%) the results did not concur. In 1 patient selective internal iliac pharmaco-angiography was read as normal (fig. 3, A). However duplex sonography with pulsed Doppler analysis before and after intracavernous injection of papaverine plus phentolamine revealed poor pulsations of the cavernous arteries with reduced blood flow (fig. 3, B). This finding was confirmed clinically because the patient had only a partial erection, reflecting the situation of reduced arterial perfusion as demonstrated with duplex sonography and pulsed Doppler analysis. In another patient pharmaco-angiography suggested occlusion of the penile arteries on the right side (fig. 4). However, duplex sonography showed normal right and left cavernous arteries with good dilatation and a normal increase in blood flow after injection of papaverine plus phentolamine (fig. 5). There also was a good erectile response. Retrospectively, we were able to demonstrate an atypical blood supply to the cavernous arteries. Only the left internal pudenda! artery was
Penile erection occurs when neural stimulation induces relaxation of the cavernous smooth muscle and arterial dilatation, with subsequent increased arterial flow to the corpora cavernosa and decrease in venous outflow. 12 ·14 • 16 Selective internal iliac angiography used to be the method of choice for evaluation of the arterial system in erectile dysfunction. 5-s. 10 • 17 Despite different techniques, good visualization of the penile arteries is possible only during the early phases of penile tumescence, when the arterial flow to the penis is maximal. Without an artificial erection caused by intracavernous injection of a vasodilator, for example, the high peripheral resistance of the cavernous bodies will not allow the small penile vessels to fill with contrast medium, leading to the incorrect diagnosis of arterial disease. These findings have been supported by other investigators.17· 18 The penile brachia! index still is a common noninvasive screening test for penile arterial insufficiency, 19 However, this test has its limitations. The individual signals from the cavernous arteries, which are the primary arteries responsible for erection, are difficult to detect with a continuous wave Doppler system. This Doppler unit detects all vessels within its acoustic beam, and most often the investigator is unable to differentiate the signals from the cavernous, dorsal and urethral arteries. With the cuff obscuring the base of the flaccid penis the Doppler probe must be placed distally, where the deep arteries are smaller and might already have branched. 2 Since a significant pathological process can be limited to 1 artery penile blood pressure measurements at 1 point only are questionable and normal results do not necessarily correlate with sufficient penile blood flow. In our material the penile brachia! index did confirm an arterial lesion in only 2 cases, which underlines the fact that calculation of the penile brachia! index without intracavernous injection of a smooth muscle relaxant is insufficient because the high peripheral resistance prevents sufficient transmission of the systemic blood pressure into the corpora cavernosa and visual control of a specific vessel being examined is not possible. The introduction of real-time sonography in combination with pulsed Doppler analysis solved this problem. 13 For the first time it was possible to gain knowledge about morphology of the cavernous arteries and corporeal tissue. Furthermore, pulsed Doppler analysis allows for objective measurement of diameter and flow in cavernous arteries before and after injection of vasoactive drugs. 2 ' 12- 15 With full erection and increasing rigidity the cavernous tissue itself often will compress the cavernous arteries and blood flow subsequently will decrease to a minimum (fig. 6). For that reason the duplex study must be performed during tumescence to avoid false pathological results. With good arterial dilatation but decreased arterial inflow there must be a proximal stenosis in or above the internal pudenda! artery. These cases are an indication to perform angiography because a localized arterial lesion might be correctable by an operation or balloon dilation. In our study the correlation between angiography and duplex sonography with pulsed Doppler analysis was 91 % . In the 2 divergent patients duplex sonography and pulsed Doppler analysis was more accurate. In 1 patient we were able to document insufficiency of the cavernous arteries with decreased inflow, which cannot be seen during angiography as long as the vessels fill with blood. In 1 patient a diagnostic error was caused by a well known variation in the anatomy of the internal pudenda! artery. 2 , 20 The angiographic diagnosis in this patient had to be revised when duplex sonography with pulsed Doppler analysis proved to be unremarkable. We conclude that duplex sonography with pulsed Doppler analysis is more accurate for the diagnosis of arteriogenic
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MUELLER AND ASSOCIATES
erectile dysfunction than selective internal iliac pharmacoangiography. Duplex sonography provides not only morphological but also functional information about arterial diameter and blood flow changes in the cavernous arteries, and information about the cavernous tissue itself. This evaluation is minimally invasive and, therefore, it can be used as a screening study. Calculation of the penile brachial index is not sufficient to evaluate patients with erectile impotence because accurate measurement of the blood pressure in the cavernous arteries is impossible even in combination with injection of vasoactive substances. REFERENCES 1. Virag, R.: lntracavernous injection of papaverine for erection failure. Letter to the Editor. Lancet, 2: 938, 1982. 2. Mueller, S. C. and Lue, T. F.: Evaluation ofvasculogenic impotence. Urol. Clin. N. Amer., 15: 65, 1988. 3. Blaivas, J. G., O'Donnell, T. F., Gottlieb, P. and Labib, K. B.: Comprehensive laboratory evaluation of impotent men. J. Urol., 124: 201, 1980. 4. Metz, P. and Bengtsson, J.: Penile blood pressure. Scand. J. Urol. Nephrol., 15: 161, 1981. 5. Ginestie, J. F. and Romier, A.: Radiologic Exploration of Impotence. The Hague: Martins Nijhoff Medical Division, 1978. 6. Gray, R. R., Keresteci, A. G., St. Louis, E. L., Grosman, H., Jewett, M. A. S., Rankin, J. T. and Provan, J. L.: Investigation of impotence by internal pudenda! angiography: experience with 73 cases. Radiology, 144: 773, 1982. 7. Huguet, J. F., Clerissi, J. and Juhan, C.: Radiologic anatomy of pudenda! artery. Eur. J. Rad., 1: 278, 1981. 8. Michal, V. and Pospichal, J.: Phalloarteriography in the diagnosis of erectile impotence. World J. Urol., 2: 239, 1987. 9. Porst, H., Lenz, M., Biihren, W. and Altwein, J.E.: Gefassveriinderungen bei primiirerund sekundiirer lmpotenz. Akt. Urol., 14: 281, 1983.
10. Struyven, J., Gregoir, W., Giannakopoulos, X. and Wauters, E.: Selective pudenda! arteriography. Eur. Urol., 5: 233, 1979. 11. Curet, P., Grellet, J., Perrin, D., Bousquet, J. C. and Jardin, A.: Technical and anatomic factors in filling of distal position of internal pudenda! artery during arteriography. Urology, 29: 333, 1987. 12. Collins, J. P. and Lewandowski, B. J.: Experience with intracorporeal injection of papaverine and duplex ultrasound scanning for assessment of arteriogenic impotence. Brit. J. Urol., 59: 84, 1987. 13. Lue, T. F., Hricak, H., Marich, K. W. and Tanagho, E. A.: Vasculogenic impotence evaluated by high-resolution ultrasonography and pulsed Doppler spectrum analysis. Radiology, 155: 777, 1985. 14. Lue, T. F., Muller, S. C., Junemann, K.-P., Fournier, G. R., Jr. and Tanagho, E. A.: Hiimodynamische Veriinderungen wiihrend der Erektion und funktionelle klinische Diagnostik der penilen Gefasse mittels Ultraschall und gepulstem Doppler. Akt. Urol., 18: 115, 1987. 15. Robinson, L. Q., Woodcock, J. P. and Stephenson, T. P.: Duplex scanning in suspected vasculogenic impotence: a worthwhile exercise? Brit. J. Urol., 63: 432, 1989. 16. Aboseif, S. R. and Lue, T. F.: Hemodynamics of penile erection. Urol. Clin. N. Amer., 15: 1, 1988. 17. Juhan, C. M., Padula, G. and Buquet, J. H.: Angiography in male impotence. In: Management of Male Impotence. Edited by A. H. Bennett. Baltimore: Williams & Wilkins, p. 73, 1982. 18. Porst, H., van Ahlen, H., Koster, 0. and Schlolaut, K. H.: Vergleich von Papaverin-induzierter Doppler-Sonographie und Angiographie in der Diagnostik der erektilen Dysfunktion. Urologe A, 27: 8, 1988. 19. Abber, J. C., Lue, T. F., Orvis, B. R., McClure, R. D. and Williams, R. D.: Diagnostic tests for impotence: a comparison ofpapaverine injection with the penile-brachia! index and nocturnal penile tumescence monitoring. J. Urol., 135: 923, 1986. 20. Bookstein, J. J. and Lange, E. V.: Penile magnification pharmacoarteriography: details of intrapenile arterial anatomy. AJR, 148: 883, 1987.
THE JOURNAL OF UROLOGY Copyright© 1990 by AMERICAN UROLOGICAL ASSOCIATION, INC.
COMPARISON OF SELECTIVE INTERNAL ILIAC PHARMACOANGIOGRAPHY, PENILE BRACHIAL INDEX AND DUPLEX SONOGRAPHY WITH PULSED DOPPLER ANALYSIS FOR THE EVALUATION OF VASCULOGENIC (ARTERIOGENIC) IMPOTENCE STEFAN C. MUELLER, HUBERTUS v. WALLENBERG-PACHALY, GUNTHER E. VOGES HANS H. SCHILD
AND
From the Departments of Urology and Radiology, Mainz Medical School, Johannes Gutenberg University, Mainz, Federal Republic of Germany
ABSTRACT
Between July 1987 and February 1988 selective internal iliac angiography was performed before and after intracavernous injection of papaverine plus phentolamine in 43 patients with erectile dysfunction. In 63% of the patients stenosis or occlusion of the pudenda! artery was found. The penile brachial index was calculated and duplex sonography with pulsed Doppler analysis was performed in 23 patients. Angiography and penile brachial index correlated in only 39% of the patients, whereas selective internal iliac angiography and duplex sonography correlated in 91 % (21 of 23). In 2 patients duplex sonography with pulsed Doppler analysis rendered better information about penile arterial perfusion than did angiography. (J. Ural., 143: 928-932, 1990) Intracavernous injection of vasoactive drugs was first described by Virag in 1982, 1 and has revolutionized the diagnostic and therapeutic approach to the impotent patient. Erectile dysfunction most often is of organic origin and vascular problems represent the most frequent cause. 2 The penile brachial index, that is the penile systolic pressure divided by the brachial systolic pressure, is popular for noninvasive diagnosis of arteriogenic impotence. However, a normal penile brachial index does not necessarily rule out significant arterial lesions. 3 • 4 Blood pressure measurements usually are done on the flaccid penis with a continuous wave Doppler unit that detects all signals in its path. Therefore, most of the penile brachial index data probably derive from the dorsal arteries, since these have the highest flow in the flaccid state. However, these arteries primarily supply the glans penis and contribute little to the corpora cavernosa, which constitute the main structure for penile erection. Selective arteriography of the internal iliac artery was believed to be the method of choice to detect arterial lesions. 5 - 10 However, the technique is not standardized. Contrast media with lower osmolarity minimize the pain and allow the examination to be performed with the patient under local anesthesia.11 Spinal anesthesia might be preferable, since blockade of the sympathetic nervous system reduces vasospasms. Artificial erection is ideal to reduce the peripheral resistance and to allow dilation of the small penile vessels for better images. Because of the invasiveness of the method few men with normal potency have been investigated and, therefore, our knowledge of the so-called normal morphology of the penile arterial blood supply is limited. Duplex sonography and pulsed Doppler analysis before and after intracavernous injection of vasoactive drugs allow for sonographic visualization of the penile arteries and provide a limited invasive functional test for the evaluation of arteriogenic impotence. 2 • 12- 15 We compared these 3 diagnostic procedures (selective internal iliac pharmaco-angiography, penile brachial index and duplex sonography with pulsed Doppler analysis) concerning the diagnostic value in the evaluation of patients with erectile dysfunction. MATERIALS AND METHODS
Between July 1987 and February 1988, 43 men 32 to 77 years old underwent selective internal iliac pharmaco-arteriography Accepted for publication October 6, 1989. 928
for the evaluation of erectile impotence. In 23 patients calculation of the penile brachial index and duplex sonography with pulsed Doppler analysis were performed. The tests were done by separate investigators.
FIG. 1. Normal selective internal iliac pharmaco-angiography of left side in 56-year-old impotent patient. A, before intracavernous injection of papaverine plus phentolamine. Thick arrow indicates urethral bulb and thin arrow shows dorsal artery. B, after intracavernous injection of 1 cc mixture of papaverine (15 mg.fee) and phentolamine (0.5 mg./ cc) during tumescence phase. Thick arrow shows urethral bulb, thin arrow shows dorsal artery and double arrows indicate cavernous artery.
EVALUATION OF ARTERIOGENIC IMPOTENCE
929
FIG. 2. Duplex sonograms with pulsed Doppler analysis. During tumescence with arterial system intact initial diameter of cavernous artery should increase up to 2-fold and peak blood flow values should be at least 25 cm. per second. A, before intracavernous injection of papaverine plus phentolamine in flaccid penis arterial diameter is 0.4 mm. and maximum flow within cavernous artery is 7 cm. per second. B, after injection of 0.5 ml. mixture of papaverine and phentolamine during tumescence phase arterial diameter is 1.0 mm. and maximum flow within cavernous artery is 26 cm. per second.
FIG. 3. A, normal selective internal iliac pharmaco-angiography after intracavernous injection of 1 ml. papaverine plus phentolamine mixture. Thick arrow indicates urethral artery, thin arrow indicates dorsal artery and double arrows show cavernous artery. B, duplex sonography during tumescence phase after intracavernous injection of 0.5 ml. drug mixture shows reduced flow (10 cm. per second), obvious thickening of arterial wall and poor arterial pulsations in patient with poor erectile response.
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MUELLER AND ASSOCIATES
FIG. 4. Selective internal iliac pharmaco-angiography after intracavernous injection of 1 ml. mixture of papaverine and phentolamine. A, visualization of 2 cavernous arteries (double arrows) on left side. Large arrow indicates dorsal artery and asterisk shows scrotal branch. B, no visualization of cavernous artery on right side. Asterisk indicates scrotal branch.
Technique of selective penile pharmaco-angiography. After both femoral arteries are punctured 5F catheters are placed into the ipsilateral internal iliac arteries. Angiography examinations are performed on the flaccid penis and during the tumescence phase after intracavernous injection of 1 cc of a mixture of 15 mg. papaverine per cc and 0.5 mg. phentolamine per cc. The flow rate was 3.5 cc per second and the total amount was 60 cc per series. The initial exposure is made 8 seconds after starting the injection of the contrast medium. Before proper placement of the catheters into the internal iliac arteries pelvic angiography is performed to exclude stenoses in the larger vessels feeding the region of interest. In a flaccid penis the contracted smooth musculature produces a high peripheral resistance such that adequate filling of the small penile vessels cannot be achieved (fig. 1, A). After intracavernous injection of a smooth muscle relaxant those vessels should be visible and are believed to be normal as long as there are no obvious caliber changes or incomplete filling (fig.1,B). Technique of calculation of the penile brachia! index. With the patient in the prone position a pediatric blood pressure cuff is placed around the penis. The penile arteries then are auscultated distal to the cuff with an 8 MHz. bidirectional continuous wave Doppler unit and systolic blood pressure values are measured. Investigations are done on the flaccid penis. For calculation of the penile brachial index the penile systolic pressure is divided by the brachial systolic pressure. The established value of 0.7 was used to differentiate normal from abnormal penile arterial pressures and a value of less than 0.7 suggested vasculogenic impotence.4
FIG. 5. Although pharmaco-angiography suggested occlusion of penile arteries on right side, duplex sonography during tumescence phase after intracavernous injection of 0.5 ml. drug mixture shows normal flow (0.27 m. per second) and good arterial dilatation (O. 7 mm.) of right cavernous artery.
Technique of duplex sonography and pulsed Doppler analysis. This study is performed with a real-time 7.5 MHz. B-scanner and a 4.5 MHz. pulsed Doppler system, both transducers integrated in 1 probe. Initially, the diameters of the cavernous arteries are measured longitudinally and transversely. Echogenicity of the arterial wall and of the cavernous smooth muscle is recorded, as well as pulsation of the vessels along the entire length of the cavernous arteries. Finally, the blood flow is measured (cm. per second) in the individual arteries. After injection of 0.5 cc of a mixture of 15 mg. papaverine per cc plus 0.5 mg. phentolamine per cc the investigation is repeated during early tumescence. Experience with this technique shows that during tumescence, with the arterial system intact, the initial diameter of the cavernous artery should increase up to 2-fold (fig. 2) and the peak blood flow values should be at least 25 cm. per second. 13- 15 RESULTS
Selective internal iliac pharmaco-angiography was normal in 16 of the 43 patients (37% ), while in 27 (63%) it demonstrated occlusion or high grade stenosis of the pelvic vessels, cavernous arteries or pudendal artery. A total of 9 patients (39%) showed good correlation between angiography and penile brachial index. However, 7 of these 9 patients had a normal angiography and penile brachial index with our criteria, while in only 2 did the penile brachial index suggest arterial insufficiency that correlated with the angiographic morphology. In 14 patients
931
EVALUATION OF ARTERIOGENIC IMPOTENCE
responsible for the blood supply with a cross-over to the right cavernous artery. DISCUSSION
FIG. 6. Duplex sonography with pulsed Doppler analysis. With full erection and increasing rigidity cavernous tissue often will compress cavernous arteries and blood flow subsequently will decrease to minimum. Therefore, duplex study must be performed during tumescence to avoid false results. A, after intracavernous injection of papaverine plus phentolamine during early tumescence high flow can be measured within cavernous artery (maximum flow 38 cm. per second). B, 5 minutes after intracavernous injection of drug mixture normal erection has developed and because of increased cavernous pressure arterial flow within cavernous artery has diminished dramatically (maximum flow 19 cm. per second).
(61 %) angiography did not correlate with penile brachia! index. Duplex sonography with pulsed Doppler analysis and angiography showed a positive correlation in 21 patients (91 %), while in 2 (9%) the results did not concur. In 1 patient selective internal iliac pharmaco-angiography was read as normal (fig. 3, A). However duplex sonography with pulsed Doppler analysis before and after intracavernous injection of papaverine plus phentolamine revealed poor pulsations of the cavernous arteries with reduced blood flow (fig. 3, B). This finding was confirmed clinically because the patient had only a partial erection, reflecting the situation of reduced arterial perfusion as demonstrated with duplex sonography and pulsed Doppler analysis. In another patient pharmaco-angiography suggested occlusion of the penile arteries on the right side (fig. 4). However, duplex sonography showed normal right and left cavernous arteries with good dilatation and a normal increase in blood flow after injection of papaverine plus phentolamine (fig. 5). There also was a good erectile response. Retrospectively, we were able to demonstrate an atypical blood supply to the cavernous arteries. Only the left internal pudenda! artery was
Penile erection occurs when neural stimulation induces relaxation of the cavernous smooth muscle and arterial dilatation, with subsequent increased arterial flow to the corpora cavernosa and decrease in venous outflow. 12 ·14 • 16 Selective internal iliac angiography used to be the method of choice for evaluation of the arterial system in erectile dysfunction. 5-s. 10 • 17 Despite different techniques, good visualization of the penile arteries is possible only during the early phases of penile tumescence, when the arterial flow to the penis is maximal. Without an artificial erection caused by intracavernous injection of a vasodilator, for example, the high peripheral resistance of the cavernous bodies will not allow the small penile vessels to fill with contrast medium, leading to the incorrect diagnosis of arterial disease. These findings have been supported by other investigators.17· 18 The penile brachia! index still is a common noninvasive screening test for penile arterial insufficiency, 19 However, this test has its limitations. The individual signals from the cavernous arteries, which are the primary arteries responsible for erection, are difficult to detect with a continuous wave Doppler system. This Doppler unit detects all vessels within its acoustic beam, and most often the investigator is unable to differentiate the signals from the cavernous, dorsal and urethral arteries. With the cuff obscuring the base of the flaccid penis the Doppler probe must be placed distally, where the deep arteries are smaller and might already have branched. 2 Since a significant pathological process can be limited to 1 artery penile blood pressure measurements at 1 point only are questionable and normal results do not necessarily correlate with sufficient penile blood flow. In our material the penile brachia! index did confirm an arterial lesion in only 2 cases, which underlines the fact that calculation of the penile brachia! index without intracavernous injection of a smooth muscle relaxant is insufficient because the high peripheral resistance prevents sufficient transmission of the systemic blood pressure into the corpora cavernosa and visual control of a specific vessel being examined is not possible. The introduction of real-time sonography in combination with pulsed Doppler analysis solved this problem. 13 For the first time it was possible to gain knowledge about morphology of the cavernous arteries and corporeal tissue. Furthermore, pulsed Doppler analysis allows for objective measurement of diameter and flow in cavernous arteries before and after injection of vasoactive drugs. 2 ' 12- 15 With full erection and increasing rigidity the cavernous tissue itself often will compress the cavernous arteries and blood flow subsequently will decrease to a minimum (fig. 6). For that reason the duplex study must be performed during tumescence to avoid false pathological results. With good arterial dilatation but decreased arterial inflow there must be a proximal stenosis in or above the internal pudenda! artery. These cases are an indication to perform angiography because a localized arterial lesion might be correctable by an operation or balloon dilation. In our study the correlation between angiography and duplex sonography with pulsed Doppler analysis was 91 % . In the 2 divergent patients duplex sonography and pulsed Doppler analysis was more accurate. In 1 patient we were able to document insufficiency of the cavernous arteries with decreased inflow, which cannot be seen during angiography as long as the vessels fill with blood. In 1 patient a diagnostic error was caused by a well known variation in the anatomy of the internal pudenda! artery. 2 , 20 The angiographic diagnosis in this patient had to be revised when duplex sonography with pulsed Doppler analysis proved to be unremarkable. We conclude that duplex sonography with pulsed Doppler analysis is more accurate for the diagnosis of arteriogenic
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erectile dysfunction than selective internal iliac pharmacoangiography. Duplex sonography provides not only morphological but also functional information about arterial diameter and blood flow changes in the cavernous arteries, and information about the cavernous tissue itself. This evaluation is minimally invasive and, therefore, it can be used as a screening study. Calculation of the penile brachial index is not sufficient to evaluate patients with erectile impotence because accurate measurement of the blood pressure in the cavernous arteries is impossible even in combination with injection of vasoactive substances. REFERENCES 1. Virag, R.: lntracavernous injection of papaverine for erection failure. Letter to the Editor. Lancet, 2: 938, 1982. 2. Mueller, S. C. and Lue, T. F.: Evaluation ofvasculogenic impotence. Urol. Clin. N. Amer., 15: 65, 1988. 3. Blaivas, J. G., O'Donnell, T. F., Gottlieb, P. and Labib, K. B.: Comprehensive laboratory evaluation of impotent men. J. Urol., 124: 201, 1980. 4. Metz, P. and Bengtsson, J.: Penile blood pressure. Scand. J. Urol. Nephrol., 15: 161, 1981. 5. Ginestie, J. F. and Romier, A.: Radiologic Exploration of Impotence. The Hague: Martins Nijhoff Medical Division, 1978. 6. Gray, R. R., Keresteci, A. G., St. Louis, E. L., Grosman, H., Jewett, M. A. S., Rankin, J. T. and Provan, J. L.: Investigation of impotence by internal pudenda! angiography: experience with 73 cases. Radiology, 144: 773, 1982. 7. Huguet, J. F., Clerissi, J. and Juhan, C.: Radiologic anatomy of pudenda! artery. Eur. J. Rad., 1: 278, 1981. 8. Michal, V. and Pospichal, J.: Phalloarteriography in the diagnosis of erectile impotence. World J. Urol., 2: 239, 1987. 9. Porst, H., Lenz, M., Biihren, W. and Altwein, J.E.: Gefassveriinderungen bei primiirerund sekundiirer lmpotenz. Akt. Urol., 14: 281, 1983.
10. Struyven, J., Gregoir, W., Giannakopoulos, X. and Wauters, E.: Selective pudenda! arteriography. Eur. Urol., 5: 233, 1979. 11. Curet, P., Grellet, J., Perrin, D., Bousquet, J. C. and Jardin, A.: Technical and anatomic factors in filling of distal position of internal pudenda! artery during arteriography. Urology, 29: 333, 1987. 12. Collins, J. P. and Lewandowski, B. J.: Experience with intracorporeal injection of papaverine and duplex ultrasound scanning for assessment of arteriogenic impotence. Brit. J. Urol., 59: 84, 1987. 13. Lue, T. F., Hricak, H., Marich, K. W. and Tanagho, E. A.: Vasculogenic impotence evaluated by high-resolution ultrasonography and pulsed Doppler spectrum analysis. Radiology, 155: 777, 1985. 14. Lue, T. F., Muller, S. C., Junemann, K.-P., Fournier, G. R., Jr. and Tanagho, E. A.: Hiimodynamische Veriinderungen wiihrend der Erektion und funktionelle klinische Diagnostik der penilen Gefasse mittels Ultraschall und gepulstem Doppler. Akt. Urol., 18: 115, 1987. 15. Robinson, L. Q., Woodcock, J. P. and Stephenson, T. P.: Duplex scanning in suspected vasculogenic impotence: a worthwhile exercise? Brit. J. Urol., 63: 432, 1989. 16. Aboseif, S. R. and Lue, T. F.: Hemodynamics of penile erection. Urol. Clin. N. Amer., 15: 1, 1988. 17. Juhan, C. M., Padula, G. and Buquet, J. H.: Angiography in male impotence. In: Management of Male Impotence. Edited by A. H. Bennett. Baltimore: Williams & Wilkins, p. 73, 1982. 18. Porst, H., van Ahlen, H., Koster, 0. and Schlolaut, K. H.: Vergleich von Papaverin-induzierter Doppler-Sonographie und Angiographie in der Diagnostik der erektilen Dysfunktion. Urologe A, 27: 8, 1988. 19. Abber, J. C., Lue, T. F., Orvis, B. R., McClure, R. D. and Williams, R. D.: Diagnostic tests for impotence: a comparison ofpapaverine injection with the penile-brachia! index and nocturnal penile tumescence monitoring. J. Urol., 135: 923, 1986. 20. Bookstein, J. J. and Lange, E. V.: Penile magnification pharmacoarteriography: details of intrapenile arterial anatomy. AJR, 148: 883, 1987.