Brief Answer:
not all prostate enlargement obstruct urine,but many can obstruct.

Detailed Answer:
Hello and welcome to Ask A Doctor services.
I have read your query and here is my advise.

* As per my surgical experience, there are various presentations of prostate
enlargement depending upon the lobe size, compression over the prostatic urethra and
other anatomic features.

* In general, if the prostate is of sufficiently large size to occlude the lumen caliber of
prostatic urethra, lobe enlargement with intra vesical extension causing compression
over the internal urethral sphincter - these are the most likely conditions present with
urinary obstruction.

* Initial presentation is of weak stream of urine, lag period to start urination, night
frequency of urine and later on there can be increase frequency of above with acute
retention of urine in some cases.

Hope this information will help you to understand the query.
Do feel free to discuss further regarding the same.

Thanks.
Dr Bhagyesh ( MS consultant surgeon )

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