Mynderse, Lance A.

Objectives To evaluate short‐term outcomes of holmium laser enucleation of the prostate ( HoLEP ) and photoselective vaporisation of the prostate ( PVP ) in patients with benign prostatic hyperplasia (BPH) and chronic urinary retention ( CUR ). Patients and Methods A retrospective chart review was performed of all patients with CUR who underwent HoLEP or PVP at our institution over a 3‐year period. CUR was defined as a persistent post‐void residual urine volume ( PVR ) of >300 mL or refractory urinary retention requiring catheterisation. Results We identified 72 patients with CUR who underwent HoLEP and 31 who underwent PVP . Preoperative parameters including median catheterisation duration (3 vs 5 months, P = 0.71), American Urological Association Symptom Index score ( AUASI ; 18 vs 21, P = 0.24), and PVR (555 vs 473 mL, P = 0.096) were similar between the HoLEP and PVP groups. The HoLEP group had a larger prostate volume (88.5 vs 49 mL, P < 0.001) and higher PSA concentration (4.5 vs 2.4 ng/mL, P = 0.001). At median 6‐month follow‐up, 71 (99%) HoLEP patients and 23 (74%) PVP patients were catheter‐free ( P < 0.001). Of the voiding patients, postoperative AUASI (3 vs 4, P = 0.06), maximum urinary flow rate (23 vs 18 mL/s, P = 0.28) and PVR (56.5 vs 54 mL, P = 1.0) were improved in both groups. Conclusions Both HoLEP and PVP are effective at improving urinary parameters in men with CUR . Despite larger prostate volumes, HoLEP had a 99% successful deobstruction rate, thus rendering patients catheter‐free.

Bladder compliance is defined as bladder’s ability to expand in volume without a significant change in pressure. The bladder wall is a multi-layered structure including a muscular layer and fibrous connective tissue. As the percent of connective tissue in the bladder interstitium increases compared to smooth muscle, the bladder becomes more rigid and less capable of expanding during filling. Currently, urodynamic studies (UDS) are considered as the clinical gold standard for bladder compliance assessment. This procedure is invasive and is associated with patient discomfort and is expensive. Ultrasound bladder vibrometry (UBV) is a novel acoustic-radiation-forced-based method for noninvasive assessment of bladder compliance. In UBV, an impulsive acoustic radiation force is focused on the bladder wall (under B-mode ultrasound image guidance) to induce vibrations which may be modeled by as a Lamb wave. High frame rate ultrasound is then utilized to detect the induced waves. This wave motion is then used to estimate the viscoelastic properties and the compliance of the bladder wall. Our results reveal a remarkable agreement between UBV and UDS cystometry measures, suggesting the potential of UBV as a viable clinical tool for the assessment of bladder compliance.

Transurethral needle ablation (TUNA) is an accepted and effective therapy for the treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). ProstivaTM(Medtronic, Shoreview, MN) is the newest-generation device, which includes a new needle design and radio frequency (RF) generator. This device creates temperatures of 120°C and necrotic lesions in less than 2.5 min. Using previously described techniques, we analyzed dynamic, gadolinium-enhanced MRIs to characterize the ablative properties of the new ProstivaTMRF device.Ten men with LUTS due to BPH were treated with the standard ProstivaTMmanufacturer–recommended protocol. The bladder neck and lateral lobes received treatment based on prostate volume and prostatic urethral length. Gadolinium-enhanced MRI sequences were obtained prior to and 1 week post-treatment. Analyze® software (Mayo Clinic Biomedical Imaging Resource, Rochester, MN) was used to evaluate MRIs. New gadolinium defects were seen in all patients following ProstivaTMtreatments. All lesions coalesced within the prostate. No defects were seen beyond the prostate, and the urethra was spared in all patients. The mean volume of necrosis was 7.56 cc, representing a mean of 11.28% of total prostate volume.Dynamic, gadolinium-enhanced MRIs demonstrate new vascular defects representing necrosis caused by ProstivaTMRF therapy of the prostate. The standard ProstivaTMRF protocol produces lesions that coalesce to create larger lesions in the bladder neck and lateral lobes. Compared to the TUNA® Precision PlusTMdevice, the ablative lesions appear comparable while produced with a shorter burn time.