Risk Factors And Mechanism For Bladder Neck Contracture After Photoselective Vaporization Of The Prostate(PVP)

ObjectivesWe investigated potential risk factors for development of BNC after Photoselective Vaporization of the Prostate(PVP) and mechanism underlying it histologically.MethodsA retrospective review of 460 consecutive patients (39-93,mean age 68.8years) undergoing PVP surgery between 2012.01 and 2015.05 in Minimally Invasive Center of Shandong Provincial Hospital was performed,and 24 of them turned into bladder neck contracture after surgery (57-83, mean age 69 years).The relationship between risk factors and BNC (age,diabetes mellitus, hypertension, urinary infection, retention, neurogenic bladder, prostate volume, PSA, operation time, catheter removal time)was determined.Factors were evaluated for their ability to predict BNC using both univariate and multivariate analysis. Treatment results for BNC were also assessed.Immunohistochemical experiments were performed to see the expression of Collagen I, and Alpha-SMA, and TGF-beta in bladder neck issue between patients with and without BNC after PVPResults(1) The mean onset time of BNC after PVP was 6.4 months (2-22).18 of 24 cases were within 6 months,while 6 more than 6 months.18 of them accepted Transurethral dilatation (≦ 3 times 16 cases,> 3 times 2 cases),6 cases Transurethral bladder neck resection. No symptoms of urinary incontinence was observed as a result of the surgery.(2)Higher morbidity of BNC occurred in patients of cigarette smoking and urological infection. In multivariate analysis, cigarette smoking and urological infection was the predictor of BNC and independent of other factors (P<0.05). Other factors such as age,diabetes mellitus, hypertension, urinary infection, retention, neurogenic bladder, prostate volume, PSA, operation time, catheter removal time made no difference on the effects (P>0.05).(3)The expression of TGF-P and Collagen I were significantly different between the bladder neck issue duiring and after PVP(P<0.05).ConclusionCigarette smoking and urinary tract infections are independent risk factors of BNC after PVP. TGF-β may play an pivotal role in the development of BNC after PVP.