الفهرس 
? Anatomy of the prostateOnly 14 pages are availabe for public view
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Abstract
Benign Prostatic Hyperplasia (BPH) is a histological diagnosis that refers to the proliferation of smooth muscle and epithelial cells within the prostatic transition zone. Bladder outlet obstruction (BOO) and/or changes in smooth muscle tone and resistance that accompany BPH often result in lower urinary tract symptoms (LUTS). (Roehrborn et al., 2008)
About half of men with BPH develop an enlarged prostate gland, called benign prostatic enlargement (BPE), and among these, about half BOO. LUTS are storage disturbances, such as daytime urinary urgency and nocturia and/or voiding disturbances, such as urinary hesitancy, weak stream, straining and prolonged voiding. Urinary hesitancy, weak stream, and nocturia are the most commonly reported LUTS. LUTS/ BPH negatively impact the quality of life. (Hollingsworth et al .2014)
Trends in medical management of LUTS/ BPH have progressed over the last 25 years. In the early 1990s, the food and Drug Administration (FDA) approval of medications for LUTS/ BPH shifted from a condition requiring a surgical intervention to a chronic condition that could be successfully managed medically. The first commonly used medications are alpha blockers (AB) and 5-alpha reductase inhibitors (5-ARIs). (Filson et al., 2013)
The American Urological Association (AUA) guideline on the management of BPH suggests that AB as alfuzosin, doxazosin, tamsulosin, and terazosin are an effective treatment options for men with LUTS/BPH. Monotherapy with 5-ARI agents as finasteride and dutasteride is another option for LUTS/BPH. Systematic reviews demonstrate that 5-ARIs are safe and effective and may be better than AB in preventing disease progression. The AUA guideline also lists AB/5-ARI combinations as appropriate and effective treatment options for men with LUTS/BPH and prostate enlargement. Newer drugs and other drug classes have shown promise in treating LUTS/BPH. A new selective AB, Silodosin, was approved by the FDA for the treatment of BPH in 2008. (Kaplan, 2013)
The mechanism of action of PDE-5 inhibitors Tadalafil in treatment of LUTS secondary to BPH is believed to be associated with increased activity of nitric oxide (NO), cyclic guanosine mono phosphate via inhibition of PDE-5 isoenzymes in different tissues of lower urinary tract causing relaxation of smooth muscle in bladder, urethra, prostate and supporting vasculature which decrease tension in the smooth muscle of the prostatic stroma and capsule. This muscle relaxation results in bladder neck opening and improvement in voiding function and it decreases detrusor muscle over activity in the bladder walls and bladder neck. (Andersson et al., 2011)