膀胱出口阻塞症狀（ＢＯＯ）是一種常見的老年疾病，而現今在臨床上的診斷依據卻又都是用非侵入式的檢測方式，這不僅影響病人的身心健康，還會有感染傳染病的危險。此計畫希望能夠透過實驗方式來驗證數值方法，發展一套非侵入式的診斷方法來協助醫師診斷膀胱出口阻塞症狀。

研究方法方面，著重在找出尿道流場中影響壓力損失的最主要因素。本研究透過醫學影像分析，利用影像資料配合影像處理技術，搭配計算流體力學驗證出有效相當於真實人體下泌尿道外形的精簡對稱的模型，並使用CNC製造方式產生。並配合實驗驗證與2維計算流體力學模擬，呈現其流場內的壓力與速度分布情形。

此外，透過本實驗方式，也可以驗證現階段計算流體力學在模擬人體排尿狀況時的準確性。也由於模型的簡化與對稱性，可透過較精密的網格與2維計算方式得到較佳的模擬結果。目的協助醫師判斷病因，並同時可減輕病人在診斷時不論心理或生理上的不適。

In order to provide reliable measured data to validate the CFD predictions, a lower urinary tract system model is fabricated based on the reconstruction of the CT images of patients with BOO. The measured data will help to identify the underlying cause of this difference between the CFD results and the clinical data. Due to the fabricational complexity of the real 3-D urethral model, the adopted model is a straight axi-symmetrical model, but having the same cross-sectional area of the real urethral. To investigate the effects of this simplification, computational study will also be directed to investigate the influences of the 2-D (axi-symmetric) and 3-D geometry on the pressure distributions.

Since the present study is to clarify through experimental measurements the cause of the mismatch between the CFD prediction and the clinical data, with the latter being 10 times larger than the former one. Based on the present measurements, this difference might not be caused by the minor loss due to the change of geometry. Instead, other mechanism, which is not accounted for in the present CFD simulation, could be presented. The likely cause is that an opening pressure should be present to open the elastic regions of the prostate and sphincter. This region is in general closed to prevent the urine from leaking from bladder. For a BOO patient, the opening pressure required is even higher.

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