World J Mens Health.  2018 Jan;36(1):79-86. 10.5534/wjmh.17039.

Enucleated Weight/Enucleation Time, Is It Appropriate for Estimating Enucleation Skills for Holmium Laser Enucleation of the Prostate? A Consideration of Energy Consumption

• Kim KH
• Kim KT
• Oh JK
• Chung KJ
• Yoon SJ
• Jung H
• Kim TB

• KMID: 2399175
• DOI: http://doi.org/10.5534/wjmh.17039

Abstract

PURPOSE
To date, the parameters for evaluating enucleation efficiency have only considered enucleation time, although operators simultaneously consume both time and energy during holmium laser enucleation of the prostate. This study was undertaken to find a better way of assessing enucleation skills, considering both enucleation time and consumed energy.
MATERIALS AND METHODS
One hundred (n=100) consecutive patients who underwent holmium laser enucleation of the prostate from April 2012 to April 2014 by a single surgeon were enrolled. Ten groups of 10 consecutive cases were used to analyze the parameters of enucleation efficiency.
RESULTS
The mean enucleation time, consumed energy, and enucleated weight were 41.3±19.2 minutes, 66.2±36.0 kJ, and 26.6±21.8 g, respectively. Concerning learning curves, like enucleation time-efficacy (=enucleated weight/enucleation time), enucleation energy-efficacy (=enucleated weight/consumed energy) also had an increasing tendency. Enucleation ratio efficacy (=enucleated weight/transitional zone volume/enucleation time) plateaued after 30 cases. However, enucleation time-energy-efficacy (=enucleated weight/enucleation time/consumed energy) continued to increase after 30 cases and plateaued at 61 to 70 cases. Furthermore, one-way analysis of variance showed that group means for enucleation time-energy-efficacy (F=3.560, p=0.001) were significantly different, but that those of enucleation ratio efficacy (F=1.931, p=0.057) were not.
CONCLUSIONS
When both time and energy were considered, enucleation skills continued to improve even after 30 cases and plateaued at 61 to 70 cases. Therefore, we propose that enucleation time-energy-efficacy should be used as a more appropriate parameter than enucleation ratio efficacy for evaluating enucleation skills.

Keyword

Lasers, solid-state; Learning curve; Prostatic hyperplasia

MeSH Terms

Holmium*
Humans
Lasers, Solid-State*
Learning Curve
Prostate*
Prostatic Hyperplasia
Holmium

Figure

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  Fig. 1 Enucleated weight and enucleation ratio (ER). ER had a lower standard deviation (SD) than enucleated weight, because ER was designed to reduce the variance shown by enucleated weight. In particular, in cases 41~50 (group 5), the SD of ER was much smaller than that of enucleated weight. The 100 patients were divided into 10 groups of 10 consecutive cases, as follows: cases 1~10 as groups 1, cases 11~20 as group 2, cases 21~30 as group 3, cases 31~40 as group 4, cases 41~50 as group 5, cases 51~60 as group 6, cases 61~70 as group 7, cases 71~80 as group 8, cases 81~90 as group 9, and cases 91~100 as group 10.

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  Fig. 2 Enucleation time and consumed energy. Gradual decreases in both enucleation time and consumed energy were observed. Like enucleation time, consumed energy also showed a decreasing trend even after 20 cases (group 2) and plateaued at 61~70 cases (group 7).

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  Fig. 3 Enucleation time-efficacy (ETE) and enucleation energy-efficacy (EEE). Gradual improvements in ETE and EEE were observed. Like ETE, EEE also tended to increase.

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  Fig. 4 Enucleation ratio efficacy (ERE) and enucleation time-energy-efficacy (ETEE). ERE plateaued after 30 cases (group 3). However, ETEE continued to increase even after 30 cases (group 3) and plateaued at 61~70 cases (group 7). This means that even after 30 cases (group 3), the operator's enucleation skills continued to increase.

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