The acronym EEP, coding for transurethral Endoscopic Enucleation of the Prostate, was introduced in 2016 by the European Association of Urology (EAU) guidelines panel on management of non-neurogenic male lower urinary tract symptoms (LUTS) and benign prostatic obstruction (BPO). Since then, a laser-based treatment, Holmium Laser Enucleation of the Prostate (HoLEP), and the current-based treatment of bipolar enucleation of the prostate (BipoLEP) are equally appreciated as valuable options for the management of benign prostatic obstruction (BPO). This was mainly inspired by the results of two meta-analyses on randomized controlled trials, comparing open prostatectomy with either Holmium Laser Enucleation of the Prostate (HoLEP) or bipolar enucleation of the prostate (BipoLEP). Prior to that, HoLEP was embraced as the only valid option for transurethral enucleation, although evidence for equivalence existed as early as 2006, but was not recognized due to a plethora of acronyms for bipolar energy-based treatments and practiced HoLEP-centrism. On the other hand, the academic discourse focused on different (other) laser approaches that came up, led by Thulium:Yttrium-Aluminum-Garnet (Tm:YAG) Vapoenucleation (ThuVEP) in 2009 and, finally, transurethral anatomical enucleation with Tm:YAG support (thulium laser enucleation of the prostate, ThuLEP) in 2010. Initially, the discourse on lasers focused on the different properties of lasers rather than technique or surgical anatomy, respectively. In and after 2016, the discussion ultimately moved towards surgical technique and accepting anatomical preparation as the common of all EEP techniques (AEEP). Since then, the unspoken question has been raised, whether lasers are still necessary to perform EEP in light of existing evidence, given the total cost of ownership (TCO) for these generators. This article weighs the current evidence and comes to the conclusion that no evidence of superiority of one modality over another exists with regard to any endpoint. Therefore, in the sense of critical importance, AEEP can be safely and effectively performed without laser technologies and without compromise.

Background: Water vapor thermal therapy (Rezum) is a minimally invasive treatment for benign prostatic enlargement (BPE). Studies reporting urodynamic results regarding the procedure are rare. Our study aimed to assess the effectiveness of Rezum on urinary outcome parameters in a consecutive series of patients and compare urodynamic data before and after treatment. Methods: We retrospectively evaluated all the patients treated with Rezum between 07/2017 and 12/2023 at our institution. Patients who had more than one Rezum intervention, those who were unable to void (i.e., catheter-dependent patients), and those with insufficient data were excluded from the data analysis. Descriptive outcomes, such as symptom scores (IPSS, IPSS-QoL), peak flow in uroflowmetry (Qmax), post-micturition residual urine volume (PVR), and prostate volume (PVol), were analyzed. If available, preoperative and postoperative urodynamic results were evaluated. Results: In total, 250 Rezum procedures were performed during the observational period. After applying the exclusion criteria, the data from 193 patients were included in the analysis. Patients achieved significant symptom relief as measured using the IPSS (46% reduction) and IPSS-QoL scores (41% reduction). Qmax improved by 4.8 ml/s, as the mean PVR significantly decreased by 50%. PVol and PSA values decreased by 30% and 27.5%, respectively. In 19/193 patients with a urodynamic evaluation, pre- and postoperative data analysis showed a significant reduction in the bladder outlet obstruction index (BOOI) by approximately 70%. Conclusions: Rezum is effective and can improve urinary symptoms. In appropriate patients, Rezum can significantly reduce the bladder outlet obstruction (BOO).

The understanding of tissue damage by laser radiation is very important for the safety in the application of surgical lasers. The objective of this study is to evaluate cutting, vaporization and coagulation properties of the 2 µm Tm:YAG laser (LISA Laser Products OHG, GER) in comparison to the 2.1 µm Ho:YAG laser (Coherent Medical Group, USA) at different laser power settings in an in vitro model of freshly harvested porcine kidneys. Laser radiation of both laser generators was delivered by using a laser fiber with an optical core diameter of 550 µm (RigiFib, LISA Laser GER). Freshly harvested porcine kidneys were used as tissue model. Experiments were either performed in ambient air or in aqueous saline. The Tm:YAG laser was adjusted to 5 W for low and 120 W for the high power setting. The Ho:YAG laser was adjusted to 0.5 J and 10 Hz (5 W average power) for low power setting and to 2.0 J and 40 Hz (80 W average power) for high power setting, accordingly. The specimens of the cutting experiments were fixed in 4 % formalin, embedded in paraffin and stained with Toluidin blue. The laser damage zone was measured under microscope as the main evaluation criteria. Laser damage zone consists of an outer coagulation zone plus a further necrotic zone. In the ambient air experiments the laser damage zone for the low power setting was 745 ± 119 µm for the Tm:YAG and 614 ± 187 µm for the Ho:YAG laser. On the high power setting, the damage zone was 760 ± 167 µm for Tm:YAG and 715 ± 142 µm for Ho:YAG. The incision depth in ambient air on the low power setting was 346 ± 199 µm for Tm:YAG, 118 ± 119 µm for Ho:YAG. On the high power setting incision depth was 5083 ± 144 µm (Tm:YAG) and 1126 ± 383 µm (Ho:YAG) respectively. In the saline solution experiments, the laser damage zone was 550 ± 137 µm (Tm:YAG) versus 447 ± 65 µm (Ho:YAG), on the low power setting and 653 ± 137 µm (Tm:YAG) versus 677 ± 134 µm (Ho:YAG) on the high power setting. Incision depth was 1214 ± 888 µm for Ho:YAG whereas Tm:YAG did not cut tissue at 5 W in saline solution. On the high power setting, the incision depth was 4050 ± 1058 µm for Tm:YAG and 4083 ± 520 µm for Ho:YAG. Both lasers create similar laser damage zones of <1 mm in ambient air and in saline solution. These in vitro experiments correspond well with in vivo experiments. Thereby, Tm:YAG offers a cutting performance, coagulation and safety profile similar to the standard Ho:YAG lasers in urological surgery.