Electrocoagulation Accounts for a Significant Portion of Discrepancy Between Preoperative Ultrasonography Prostate Size Estimation and Resected Tissue Weight

Overview of Benchtop Models for Comparison of Surgical Treatments for Benign Prostatic Hyperplasia

PURPOSE OF REVIEW

Benign prostatic hyperplasia (BPH) is a disease of the lower urinary tract which often requires surgical treatment. Recently, there has been a deluge of new treatment options, rarely validated or compared to current treatments on a benchtop model. The purpose of this review is to examine the literature and report which benchtop models are currently being used, which therapies have been tested on them, and what outcomes are being studied on each model.

RECENT FINDINGS

There are various benchtop models to choose from, each with their unique benefits and drawbacks. Perfused porcine kidney models are used to assess bleeding on the benchtop, ex-vivo human prostate helps to see specific interactions of devices with the prostatic tissue, and all other models have evaluated tissue ablation rates and depth of coagulation. There are currently no synthetic or non-animal tissues being used for this purpose, and surgical techniques such as enucleation, water-jet ablation, prostate stents, and water vapor thermal therapy have no representation in these benchtop tests. Benchtop testing serves an important role in the evaluation and comparison of surgical treatments for BPH. This testing allows these therapies to be objectively compared to one another, helping novel medical devices in their path to market and urologists make treatment decisions. Future directions may include further validation of the animal models currently being used and development of synthetic models which mimic the prostate on the benchtop.

Utilizing Preoperative Magnetic Resonance Imaging to Self-assess Enucleation Ratio in Holmium Laser Enucleation of the Prostate

OBJECTIVE

To determine if transition zone (TZ) volume as measured by magnetic resonance imaging (MRI) correlates closely with specimen weight and postoperative prostate-specific antigen (PSA) and to determine if this correlation improved with increased experience. We hypothesize that information from a preoperative MRI can be leveraged to self-assess competency in holmium laser enucleation of the prostate (HoLEP).

METHODS

From August 2018 to June 2021 567 men were identified who underwent HoLEP by a single surgeon and had their data entered into a database. Ninety-seven men were identified who had an MRI in our image archives. A radiologist blinded to the specimen weight measured the transition zone (TZ) using image analysis software. TZ volume was then correlated with specimen weight for the entire study period and subdivided into four consecutive periods. Preoperative and Postoperative PSA data was analyzed.

RESULTS

Seventeen percent of men who underwent HoLEP at our institution had an MRI preoperatively. The TZ to total prostate volume ratio was 70%. The overall correlation coefficient between TZ volume and specimen weight was 0.914 (P-value <.001). There was no statistically significant improvement in correlation coefficient over time when divided into four equal subgroups. Median PSA reduction was 91% (7.9-0.7 ng/dL).

CONCLUSION

Preoperative MRI derived TZ volume correlates closely with specimen weight. We present a reference cohort from a high volume HoLEP center to facilitate HoLEP learners to self-assess competency. Lack of increased correlation over time is likely due to an experienced HoLEP surgeon who is on the flatter portion of his learning curve.