Melman A, Serels S
Department of Urology, Montefiore Medical Center/Albert Einstein College of Medicine, Bronx, New York 10467, USA.
Int J Impot Res. 2000 Oct;12 Suppl 4:S133-9. doi: 10.1038/sj.ijir.3900592.
Priapism is a prolonged, painful, penile erection that fails to subside despite orgasm. An erection lasting longer than 4-6 h is considered to be priapic; nevertheless, pain does not usually ensue until 6-8 h have elapsed. Priapism is considered a failure of the detumescence mechanism, which may be due to excess release of contractile neurotransmitters, obstruction of draining venules, malfunction of the intrinsic detumescence mechanism, or prolonged relaxation of intracavernosal smooth muscle. There are essentially two main types of priapism: high flow (non-ischemic) and low flow (ischemic). Low flow priapism is the more common form, and it is associated with a decrease in venous outflow and vascular stasis that, in turn, cause tissue hypoxia and acidosis. This form of priapism is usually quite painful because of tissue ischemia. Penile blood aspirated from cavernous spaces appears dark in color. Immediate treatment is necessary or penile fibrosis will ensue. High flow priapism is usually due to trauma, although, on rare occasions it has been idiopathic or due to sickle cell disease. The hallmark of this type of priapism is an increase in arterial inflow in the setting of normal venous outflow. Aspirated penile blood is noted to be bright red and has a high pO(2). This form of priapism is not usually painful because it is non-ischemic. Treatment is dependent on the wishes of the patient but is not mandatory. International Journal of Impotence Research (2000) 12, Suppl 4, S133-S139.
阴茎异常勃起是一种持续时间长且伴有疼痛的阴茎勃起状态，即便经历性高潮也不会消退。勃起持续时间超过4 - 6小时即被视为阴茎异常勃起；不过，通常在6 - 8小时后才会出现疼痛。阴茎异常勃起被认为是阴茎消肿机制出现故障，其原因可能是收缩性神经递质释放过多、引流小静脉受阻、内在消肿机制功能异常或海绵体内平滑肌长时间松弛。阴茎异常勃起主要有两种类型：高流量型（非缺血性）和低流量型（缺血性）。低流量型阴茎异常勃起更为常见，它与静脉流出减少和血管淤滞相关，进而导致组织缺氧和酸中毒。这种类型的阴茎异常勃起通常因组织缺血而非常疼痛。从海绵体空间抽取的阴茎血液颜色较深。必须立即进行治疗，否则会导致阴茎纤维化。高流量型阴茎异常勃起通常由外伤引起，不过，极少数情况下也可能是特发性的或由镰状细胞病导致。这种类型阴茎异常勃起的特征是在静脉流出正常的情况下动脉流入增加。抽取的阴茎血液呈鲜红色，氧分压较高。这种类型的阴茎异常勃起通常不会疼痛，因为它是非缺血性的。治疗取决于患者的意愿，但并非强制要求。《国际阳痿研究杂志》（2000年）12卷，增刊4，S133 - S139。
