BPH is a common disease in aged men that affects quality of life. In the Baltimore Longitudinal Study of Aging, >60% of men aged ≥60 years have some degree of obstructive symptoms caused by BPH . TURP is regarded as the reference standard in the surgical treatment of BPH . Lately, surgical extirpative techniques using lasers, such as holmium and thulium lasers, have been gaining attention as a treatment option for symptomatic BPH. Since Gilling et al.  first reported on HoLEP in 1996, it has been proven to be one of the most strictly analyzed surgical treatments for the obstructive symptoms of BPH. More than four randomized controlled trials on this modality have been published [14–17]. More recent descriptions of various approaches to en bloc procedures have been published, mainly to address the goals of improving the effectiveness of enucleation, better visualization on the surgical plane, and optimal safety relative to those of the traditional three-lobe method [18–20]. However, the arduous surgical learning curve and potential long operative times of en bloc HoLEP have been obstacles to its extensive use, despite its obvious advantages. Thus, identifying patient groups and tissue characteristics that may increase operative times may help in appropriate patient selection, proper scheduling of the operating room time, and matching the surgeons’ experience level to the expected difficulty.
Generally, en bloc ‘no-touch’ enucleation involves an “outside-in” procedure that starts at the apex and completely uses a Ho:YAG laser to remove the transitional zone of the prostate. Moreover, the Ho:YAG laser in the vaporization procedure is manipulated as a cutting device. Enucleation time significantly depends on visualization, gland size, and recognition of the dissection plane. Enucleated adenoma weight is predicted to largely affect enucleation times. Several previous studies have reported that the HoLEP operative efficiency increases with larger prostate volumes [21, 23]. In our current series, as expected, regardless of enucleated tissue weight or prostate volume on TRUS, the increase in efficiency was shown by a positive slope on the plots of efficiency versus prostate volume.
Giorgio et al.  evaluated the effect of chronic inflammation of the prostate and found that patients with a history of chronic prostatic inflammation have an apparent higher risk of retention. Chronic urinary catheterization and recurrent UTI can hypothetically increase prostate inflammation, which may change the natural morphological architecture, increase gland volume, and obscure the natural plane between the prostate capsule and adenoma. These inflamed prostate tissues may also cause bleeding or oozing during surgery, resulting in poorer visualization and more complicated dissection during en bloc ‘no-touch’ enucleation. In our study, history of UTI history was associated with a 24-min increase in enucleation time (Table 3). However, a Foley in-dwelling catheter at the time of HoLEP was not associated with increased time in the surgical steps of enucleation.
Recent studies have assessed the safety of HoLEP in patients who were taking antiplatelet agents long term and concluded that HoLEP was not a danger to this particular population . This conclusion is expected because the Ho:YAG laser coagulates the bleeding of enucleated tissue with efficiency . We examined whether long-term antiplatelet agents would influence enucleation time and initially hypothesized that because long-term antiplatelet agents could increase bleeding and negatively influence visualization of the operative field, it may increase enucleation time. As expected, our study found that history of long-term chronic antiplatelet agents was related to an apparent increase in enucleation time (Table 3).
Monn. et al.  published a retrospective cohort analysis which included a total of 960 patients between 1998 and 2013 illustrating predictor of enucleation and morcellation time during conventional three-lobe HOLEP method. The authors concluded that a history of UTI is associated with an increase in operative time whereas anticoagulation is related to decrease in operative time. The difference impact on the role of antiplatelet agents in surgical time between our present study and the previous published report, in our opinion, is based on difference techniques. The application of en bloc method allows complete adenoma enucleation following surgical capsule at any time, and non-optimal visibility by oozing in patients of long-term antiplatelet agents might lead to increase enucleation time. However, the overall efficiency in the present study (0.5 g/min) indicated no obvious inferior difference compared with earlier randomized clinical trials on the efficiency of retrieval (0.48 g/min) . We believed laminar irrigation between the capsule and enucleated adenoma in en bloc ‘no-touch’ technique help to maintain visualization throughout the procedure compared with chaotic irrigation in the classic 3-lobe method.
The influence of 5ARi use on prostate tissue quality is known to alter the glandular-to-stromal ratio and reduce the volume of overall glandular tissue [26, 27]. For this reason, hypothetically, long-term 5ARi use might increase the prostate fibrous content, which could lead to more difficult enucleation. However, Sandfeldt et al.  found that blood loss volume decreased during TURP after using finasteride for 3 months preoperatively. This might decrease bleeding and positively effect visualization during surgery, leading to a faster enucleation rate. Nevertheless, in our study, we found that history of 5ARi use was not actually related to faster enucleation rate . Warner et al.  reported the influence of 5ARi use on HoLEP and found that it did not affect HoLEP operative times or outcomes, which is consistent with our study results. In the current study, we found no clear evidence of a relationship between overall HoLEP surgical time and 5ARi use.
We examined whether presence of “beach ball” and previous TURP would impact enucleation operative time. It is believed that beach balls are easy to enucleate relatively. However, multiple beach balls located diffusely in the peripheral edges of adenoma might cause difficult recognition of the dissection plane, and prolong the operative time. The factor of previous TURP might result in hard to identify the correct plane because of natural anatomical structure undermined. We assumed that each factor mentioned above might have a potential role in the prostatic tissue histological architecture and natural plane. Interestingly, neither previous TURP nor presence of beach ball during surgery had a notable effect on enucleation efficiency. Identification of factors associated with development of these difficult prostate tissues is worth studying in the future. We speculate that because of anticipated concerns regarding the effect of dense tissue or a complicated plane, surgeon's great surgical experience could reduce the effect of difficult recognition of the plane between the capsule and enucleated adenoma on overall operative time.
In the current study, all complications after en bloc ‘no-touch’ HoLEP were evenly distributed among the groups according to the HoLEP specimen weight. A prospective larger randomized trial of 61 men with prostate sizes of 40–200 g was reported by Tan et al.  in which 30 and 31 patients underwent TURP had HoLEP, respectively. This randomized trial reported that mean Foley in-dwelling time and hospital stay were shorter in HoLEP than in TURP. Outcomes and complication rates were similar in both procedures. The above study supports the statement of Kuntz et al.  that HoLEP voiding improvement and perioperative morbidity are not based on prostate gland size. There were rather high range of enucleation time(up to 220 minutes) and morcellation time (up to 130 minutes) been noted in the present study. Although relative longer operation time, we didn’t divided procedure into stages or delayed morcellation, since we believe that this will ultimately accelerate patient recovery. No elevated urethral stricture rate in long operation time group of en bloc ‘no-touch’ HoLEP. At the time of the study, our en bloc ‘no-touch’ HoLEP method had been applied for only 1.5 years. Consequently, no long-term follow up data were practicable for interpretation.
This study had some limitations. First, because of its retrospective design, it was intrinsically limited despite inclusion of consecutive patients to avert potential selection bias. Subsequently, we did not consider whether energy usage changed according to the different patient characteristics, but enucleation efficiency may vary depending on the amount of laser energy used. Kim et al.  reported a new parameter combining enucleation time and energy consumption to estimate enucleation skills of the operators. It demonstrate that energy consumption decreases as the enucleation technique of a surgeon develops. This trend suggests that as the surgeon’s surgical enucleation skill progresses, less energy is used and efficiency is increased. Lastly, surgeries in the study patient group were performed by a single surgeon. Therefore, we recommend that this enucleation time prediction model of en bloc ‘no-touch’ HoLEP should be examined by multiple surgeons hereafter to determine if it is generally reproducible and acceptable. Despite these limitations, this study examined how preoperative characteristics may affect enucleation times in patients undergoing en bloc ‘no-touch’ HoLEP for BPH and provided a possible enucleation time prediction model. Additionally, the study also found that prostate gland size was not associated with increases in complications after HoLEP.