Internal pudendal

The penis is mainly supplied by the internal pudendal artery, and three major sets of veins, superficial, intermediate, and deep veins, drain it. Drug-induced changes in neurotransmitter action can affect local blood flow. Vascular supply, intrinsic smooth muscles of the penis, and adjacent striated muscles are controlled by nerves arising from the thoracolumbar sympathetic, the lumbosacral parasympathetic, and the lumbosacral somatic systems. The pudendal nerve is the major somatic pathway innervating the male genitalia. 

Figure 9.52 shows the blood supply to the rectal area. The main artery to the rectum is the superior rectal (haemorrhoidal) artery. Veins of the inferior part of the submucous plexus become the rectal veins, which drain to the internal pudendal veins. Dmg absorption takes place through this venous network. Superior haemorrhoidal veins connect with the portal vein and thus transport dmgs absorbed in the upper part of the rectal cavity... 

Kawakami M, Minagawa T, Inoue H, et al. (2003) Successful treatment of arterial priapism with radiologic selective transcatheter embolization of the internal pudendal artery. Urology 61 645... 

Another case features a transient necrotic-appearing area on the right labium minus 5 days post UAE in a 38-year-old woman [110]. This was thought to be due to non-target labial embolization during UAE, perhaps of the internal pudendal artery. Spontaneous resolution occurred during the ensuing 4 weeks. 

Fig. 13.2. a The most common anatomy of the internal pudendal artery origin, b Selective catheterization of the internal pudendal artery with distal division into the deep and dorsal branch... 

Fig. 13.3. Embolization of both internal pudendal arteries with coils in a patient with priapism and sickle cell disease. The aim of this treatment was to create permanent impotence and to prevent fibrosis...

Anatomic Considerations The internal pudendal artery, a terminal branch of the anterior division of the internal iliac artery supplies the external genitalia. With extension to inguinal and iliac lymph nodes, additional supply originates from the obturator branch of the internal iliac artery, the inferior epigastric artery from the external iliac artery and the superficial epigastric artery and the superficial and deep external pudendal branches of the common femoral arteries. 

LA. Infusion Our experience with percutaneous intraarterial transcatheter chemotherapy in patients with recurrent carcinoma of the vulva and penis is limited. Therapy is usually delivered through the internal pudendal branch of the internal iliac artery, the external pudendal branch of the external iliac artery, and the external pudendal branch of the deep femoral artery. The chemotherapy regimen consisted of mitomycin C (10 mg/m over 24 h), bleomycin (20-40 mg/m over 24 h), and dsplatin (100 mg/m over 2 h). Although the number of patients treated under this regimen is too small for analysis, dramatic responses have been observed in several patients. 

The main source of blood supply to the penis (Fig. 2.2a) is usually through the internal pudendal artery, a branch of the internal iliac artery. In many instances, however, accessory arteries arise from the external iliac, obturator, vesical, and/or femoral arteries, and may occasionally become the dominant or only arterial supply to the corpus cavernosum (Breza et al. 1989). Damage to these accessory arteries during radical prostatectomy or cystectomy may result in vasculogenic erectile dysfunction (ED) after surgery (Aboseif et al. 1994 Kim et al. 1994). 

The internal pudendal artery becomes the common penile artery after giving off a branch to the perineum. The three branches of the penile artery are the dorsal, bulbourethral, and cavernous arteries. The cavernous artery is responsible for tumescence... 

Emissary veins from the infrapubic penis drain the proximal corpora cavernosa and join to form cavernous and crural veins. These veins join the periurethral veins from the urethral bulb to form the internal pudendal veins. 

Much more complex is the dinical evaluation of patients who show PSV values between 25 and 35 cm/s. This range of values is commonly observed in older subjects with mild erectile dysfunction (Fig. 6.14). Probably they have a stiffness of the arterial walls with intimal thickening and reduced response to PGEl stimulation, secondary to an endothelial lesion and reduced NO production. In these patients stenosis or obstruction of the precavernosal arteries can be suspected and the flow study of these larger vessels should be performed. The terminal branches of the internal pudendal artery can be explored with a high linear frequency probe positioned in the perineal area under the scrotum. 

Direct identification of the arterial-lacunar fistula is obtained with Doppler techniques. Color Doppler ultrasonography allows identification of the lesion in virtually all patients only one case has been reported in which the fistula was not detected both at color Doppler and at angiography, but became evident only after empiric selective embolization of the contralateral internal pudendal artery (Ankem et al. 2001). 

Postraumatic penile arterial obstruction characteristically involves the proximal portion of the dorsal penile and cavernosal arteries and the distal internal pudendal artery at the level of the urogenital diaphragm. The integrity of arterial vascular supply to the penis can be assessed by Doppler interrogation of the cavernosal arteries. A peak systolic velocity of 25 cm/s or less after prostaglandin El intracavernosal injection reflects arterial insufficiency (Fig. 12.11). 

Fig. 12.11a-c. Postraumatic erectile dysfunction. A 32-year-old patient who received pelvic bone fractures during a traffic accident, a Doppler interrogation of the cavernosal arteries shows low velocity flows of 12 cm/s, consistent with postraumatic arterial insufficiency, b Left internal pudendal arteriogram shows interruption of the vascular supply to the penis with no opacification of the cavernosal artery, c MDCT angiography demonstrates the same vascular features non-invasively... 

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