Department of Radiology, Addenbrooke's Hospital and University of Cambridge, Cambridge, CB2 0QQ, UK.
CamPARI Clinic, Addenbrooke's Hospital and University of Cambridge, Cambridge, CB2 0QQ, UK.
Eur Radiol. 2017 Dec;27(12):5236-5243. doi: 10.1007/s00330-017-4905-x. Epub 2017 Jul 4.
To prospectively investigate the longitudinal effect of ejaculatory abstinence on MRI-measured seminal vesicle (SV) volume and whole-prostate ADC over consecutive days.
15 healthy male volunteers (mean 35.9 years, range 27-53) underwent 3-T MRI at baseline and 1, 2 and 3 days post-ejaculation. Prostate and SV volumes were derived by volume segmentation and whole-gland apparent diffusion coefficient (ADC) values calculated. A mixed-effects linear regression compared ADC values and prostate/seminal vesicle volumes in each volunteer between studies in a pairwise manner.
All subjects completed the four MRIs. Mean prostate volume was 22.45 cm (range 13.04-31.21 cm), with no change between the four studies (p = 0.89-0.99). 13/15 subjects showed SV volume reduction from baseline to day 1, with group-mean decreasing from 6.45 to 4.80 cm (-25.6%, p < 0.001), and a significant reduction from baseline to day 2 (-18.1%, p = 0.002). There was a significant volume increase from both day 1 (+21.3%, p = 0.006) and day 2 (+10.2%, p = 0.022) to day 3 post-ejaculation. There was a significant reduction in ADC from 1.105 at baseline to 1.056 × 10 mm/s at day 1 (mean -4.3%, p = 0.009).
The longitudinal effect of ejaculation on SV volume was demonstrated. Significant reductions in SV volume and whole-gland ADC were observed post-ejaculation, supporting a 3-day period of abstinence before prostate MRI.
• Seminal vesicle volume significantly reduced 24 h post-ejaculation remaining reduced at day 2 • Seminal vesicle fluid volume significantly increased from day 1 to day 3 post-ejaculation • There was a significant reduction in whole-gland prostate ADC values day 1 post-ejaculation • 3-day abstinence from ejaculation is required to ensure maximal seminal vesicle distension.
前瞻性研究连续几天内射精禁欲对 MRI 测量的精囊（SV）体积和整个前列腺 ADC 的纵向影响。
15 名健康男性志愿者（平均年龄 35.9 岁，范围 27-53 岁）在基线和射精后 1、2 和 3 天进行 3-T MRI。通过体积分割得出前列腺和 SV 体积，计算整个腺体表观扩散系数（ADC）值。混合效应线性回归比较了每个志愿者在两次研究之间的 ADC 值和前列腺/精囊体积。
所有受试者均完成了 4 次 MRI。平均前列腺体积为 22.45 cm（范围 13.04-31.21 cm），四次研究之间无变化（p = 0.89-0.99）。13/15 名受试者的 SV 体积从基线到第 1 天减少，组平均值从 6.45 减少到 4.80 cm（减少 25.6%，p < 0.001），从基线到第 2 天减少（减少 18.1%，p = 0.002）。从第 1 天（增加 21.3%，p = 0.006）和第 2 天（增加 10.2%，p = 0.022）到射精后第 3 天，SV 体积显著增加。从基线的 1.105 到第 1 天的 1.056×10 mm/s（平均减少 4.3%，p = 0.009），ADC 显著降低。
射精对 SV 体积的纵向影响得到了证明。射精后 SV 体积和整个腺体 ADC 显著减少，支持在前列腺 MRI 前禁欲 3 天。
• 射精后 24 小时 SV 体积显著减少，第 2 天仍减少• 射精后第 1 天至第 3 天 SV 内液体积显著增加• 射精后第 1 天整个前列腺 ADC 值显著降低• 需要 3 天的射精禁欲以确保最大程度的精囊扩张。
