Introduction and objectives:
To assess whether the recovery of urinary continence after holmium laser enucleation of the prostate (HoLEP) is associated with preoperative magnetic resonance imaging MRI factors.
Methods:
From Jan. 2016 to Mar. 2018, there were 126 patients underwent HoLEP in our hospital because of LUTs caused by BPH. All the procedures were performed by a single surgeon with more than 200 HoLEP experience(Prof. Xiao). Perioperative data were recorded including PSA, IPSS score, volume measured by ultrasound, operation time and estimated blood loss. We performed MRI to every patients preoperatively, we measured the following factors: length (LP), width (WP), height (HP) and volume (PV) of the prostate,membranous urethral length (MUL), intravesical prostatic protrusion length(IPPL), urethral wall thickness (UWT), levator ani muscle (LAM) and obturator internus muscle (OIM) thickness. The membranous urethral length (MUL) was measured on coronal magnetic resonance imaging (MRI) images of each patient and was defined as the distance from the prostatic apex to the entry of the urethra into the penile bulb. IPPL was measured on MRI as the vertical distance from the tip of the protruding prostate to the base of the urinary bladder. The recovery of urinary continence was recorded postoperatively, during an 8 weeks follow up.
Results:
The continent rate of 2, 4, 8 weeks postoperatively were 81.0%, 89.7%, and 96.6%, respectively. Univariate obtained differences in Age, PV, MUL, and IPLL after 2 weeks of the operation. Multivariate analysis showed Age (P=0.001), MUL (P= 0.001) and IPLL (P= 0.012) were the independence factors for the recovery of continence of 2 weeks after surgery. Univariate obtained differences in PV, MUL, and IPLL after 4 weeks of the operation. Multivariate analysis showed Age (P=0.001) and MUL (P= 0.013) were the independence factors for the recovery of continence of 4 weeks after surgery. No significant association except age (P=0.012) was found between MRI factors to the recovery of continence of 8 weeks after surgery.
Conclusions:
MRI is a useful tool to predict UI after RP in early stage (1 month) after the procedure. The MUL and IPPL are well-identified structures that are involved in incontinence after HoLEP.
