Editing Benign prostatic hyperplasia (section)

===Imaging and other investigations===
Uroflowmetry is done to measure the rate of urine flow and total volume of urine voided when the subject is urinating.<ref name="pmid30614059">{{cite journal | vauthors = Gammie A, Drake MJ | title = The fundamentals of uroflowmetry practice, based on International Continence Society good urodynamic practices recommendations | journal = Neurourology and Urodynamics | volume = 37 | issue = S6 | pages = S44–S49 | date = August 2018 | pmid = 30614059 | doi = 10.1002/nau.23777 | s2cid = 58586667 | doi-access = free }}</ref>

Abdominal ultrasound examination of the prostate and [[kidney]]s is often performed to rule out [[hydronephrosis]] and hydroureter. Incidentally, cysts, tumours, and stones may be found on ultrasound. [[Urinary retention#Diagnosis|Post-void residual volume]] of more than 100 ml may indicate significant obstruction.<ref>{{Cite journal | vauthors = Foo KT |date=June 2013 |title=The Role of Transabdominal Ultrasound in Office Urology |journal=Proceedings of Singapore Healthcare |language=en |volume=22 |issue=2 |pages=125–130 |doi=10.1177/201010581302200208 |s2cid=74205747 |issn=2010-1058|doi-access=free }}</ref> Prostate size of 30 cc or more indicates enlargement of the prostate.<ref name="pmid31340802">{{cite journal | vauthors = Aprikian S, Luz M, Brimo F, Scarlata E, Hamel L, Cury FL, Tanguay S, Aprikian AG, Kassouf W, Chevalier S | title = Improving ultrasound-based prostate volume estimation | journal = BMC Urology | volume = 19 | issue = 1 | pages = 68 | date = July 2019 | pmid = 31340802 | pmc = 6657110 | doi = 10.1186/s12894-019-0492-2 | doi-access = free }}</ref>

[[Prostatic calculi|Prostatic calcification]] can be detected through transrectal ultrasound (TRUS). Calcification is due to solidification of prostatic secretions or calcified [[corpora amylacea]] ([[hyaline]] masses on the prostate gland). Calcification is also found in a variety of other conditions such as prostatitis, [[Chronic prostatitis/chronic pelvic pain syndrome|chronic pelvic pain syndrome]], and prostate cancer.<ref>{{cite journal | vauthors = Kitzing YX, Prando A, Varol C, Karczmar GS, Maclean F, Oto A | title = Benign Conditions That Mimic Prostate Carcinoma: MR Imaging Features with Histopathologic Correlation | journal = Radiographics | volume = 36 | issue = 1 | pages = 162–175 | date = January 2016 | pmid = 26587887 | pmc = 5496681 | doi = 10.1148/rg.2016150030 }}</ref><ref>{{cite journal | vauthors = Singh S, Martin E, Tregidgo HF, Treeby B, Bandula S | title = Prostatic calcifications: Quantifying occurrence, radiodensity, and spatial distribution in prostate cancer patients | journal = Urologic Oncology | volume = 39 | issue = 10 | pages = 728.e1–728.e6 | date = October 2021 | pmid = 33485763 | pmc = 8492071 | doi = 10.1016/j.urolonc.2020.12.028 }}</ref> For those with elevated levels of PSA, TRUS guided biopsy is performed to take a sample of the prostate for investigation.<ref name="pmid20199941">{{cite journal | vauthors = Mitterberger M, Horninger W, Aigner F, Pinggera GM, Steppan I, Rehder P, Frauscher F | title = Ultrasound of the prostate | journal = Cancer Imaging | volume = 10 | issue = 1 | pages = 40–48 | date = March 2010 | pmid = 20199941 | pmc = 2842183 | doi = 10.1102/1470-7330.2010.0004 }}</ref> Although MRI is more accurate than TRUS in determining prostate volume, TRUS is less expensive and almost as accurate as MRI. Therefore, TRUS is still preferred to measure prostate volume.<ref name="pmid17495490">{{cite journal | vauthors = Lee JS, Chung BH | title = Transrectal ultrasound versus magnetic resonance imaging in the estimation of prostate volume as compared with radical prostatectomy specimens | journal = Urologia Internationalis | volume = 78 | issue = 4 | pages = 323–327 | date = 2007 | pmid = 17495490 | doi = 10.1159/000100836 | s2cid = 10731245 }}</ref>