- Email: [email protected]
A New Laser Platform for Holmium Laser Enucleation of the Prostate: Does the Lumenis Pulse 120H Laser Platform Improve Enucleation Efficiency?
Accepted Manuscript Title: A New Laser Platform for Holmium Laser Enucleation of the Prostate: Does the Lumenis Pulse 120H Laser Platform Improve Enucleation Efficiency? Author: Karen L. Stern, Sean B. McAdams, Stephen S. Cha, Haidar M. AbdulMuhsin, Mitchell R. Humphreys PII: DOI: Reference:
S0090-4295(16)30968-2 http://dx.doi.org/doi: 10.1016/j.urology.2016.12.022 URL 20200
To appear in:
Urology
Received date: Accepted date:
28-9-2016 14-12-2016
Please cite this article as: Karen L. Stern, Sean B. McAdams, Stephen S. Cha, Haidar M. AbdulMuhsin, Mitchell R. Humphreys, A New Laser Platform for Holmium Laser Enucleation of the Prostate: Does the Lumenis Pulse 120H Laser Platform Improve Enucleation Efficiency?, Urology (2016), http://dx.doi.org/doi: 10.1016/j.urology.2016.12.022. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
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[Category: Prostatic Diseases and Male Voiding Dysfunction] A New Laser Platform for Holmium Laser Enucleation of the Prostate: Does the Lumenis Pulse 120H Laser Platforma Improve Enucleation Efficiency? Karen L. Stern, MD Sean B. McAdams, MD Stephen S. Cha Haidar M. Abdul-Muhsin, MB, ChB Mitchell R. Humphreys, MD
Author Affiliations: Department of Urology (Drs Stern, McAdams, Abdul-Muhsin, and Humphreys), Mayo Clinic Hospital, Phoenix, Arizona, and Biostatistics (Mr Cha), Mayo Clinic, Scottsdale, Arizona. a
Mayo Clinic does not endorse specific products or services included in this
article. Reprints: Mitchell R. Humphreys, MD, Department of Urology, Mayo Clinic Hospital, 5777 E Mayo Blvd, Phoenix, AZ 85054 ([email protected]). Presented in abstract form at the 33rd World Congress of the Endourology and SWL, London, United Kingdom, October 1-4, 2015. Keywords: benign prostatic hyperplasia; holmium; laser; obstruction; prostate Acknowledgment: The authors did not receive any financial support. Research Support and Conflict of Interest: The authors did not receive any research support. No competing financial interests exist. Text word count: 1,745 Abstract word count: 247 No. of tables: 2 No. of figures: 0
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Running title: Enucleation Efficiency in HoLEP Publisher: To expedite proof approval, send proof via email to [email protected]. ©2016 Mayo Foundation for Medical Education and Research Abstract Objectives: To determine whether the recently introduced Lumenis Pulse 120H laser platform, which offers a dual-pedal footswitch and preset energy modes to easily switch among laser settings, facilitates a more efficient process in holmium laser enucleation of the prostate (HoLEP) for surgical treatment of benign prostatic hyperplasia. Methods: Patients at a single institution who underwent HoLEP with the new Lumenis Pulse 120H laser platform were matched 1:2 with patients who underwent the procedure with the previously used 100-watt VersaPulse single-pedal laser platform. Matching was performed by using propensity scores calculated by a logistic model that considered preoperative transrectal ultrasound prostate volume and patient age. The primary outcome was enucleation efficiency of each platform, determined by the weight of prostate tissue resected and enucleation time. The McNemar test and a conditional logistic model were used to associate predictors and cases. Results: Twenty-nine patients who underwent HoLEP with the Lumenis Pulse 120H platform were matched with 58 patients who underwent the procedure with the 100-watt platform. We observed statistically significant differences in operating room total time, procedure time, and enucleation time. Other perioperative and postoperative outcomes were comparable between the 2 groups. Enucleation efficiency was similar between the 2 laser platforms (0.89 g per minute in the control group vs 0.84 g per minute in the Lumenis Pulse 120H group). Conclusions: The efficiency of the new Lumenis Pulse 120H laser platform is comparable to the 100-watt VersaPulse laser platform in HoLEP when comparing grams of tissue enucleated per minute.
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Abbreviations BPH, benign prostatic hyperplasia HoLEP, holmium laser enucleation of the prostate OR, operating room TRUS, transrectal ultrasonography
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Introduction Benign prostatic hyperplasia (BPH) affects approximately 50% of men older than 50 years and 88% of men age 80 through 89 years, often leading to decreased quality of life and ultimately requiring treatment (1,2). Holmium laser enucleation of the prostate (HoLEP) has been suggested as the gold standard for surgical treatment for BPH (1,3). First described in 1996 by Gilling et al (4), HoLEP has been shown to benefit men with obstructive symptoms independent of prostate size and to have durable results (1,4,5). Multiple technological and procedural advances have been made over the past several years to improve the efficacy and efficiency of the procedure, including new morcellators, compatibility with multiple scope manufacturers, alterations in technique to allow more persons to learn the technique, and the recent delivery of a new 120H laser platform (Lumenis Pulse; Lumenis Ltd) (6). The platform allows for preset energy modes, and a dual foot pedal allows the surgeon to switch between 2 laser settings easily. Typically, lower energy settings are used for hemostasis and near the prostatic apex; higher energy settings are used for most of the enucleation. Theoretically, the dual foot pedal should allow the enucleation portion of the procedure to proceed more efficiently. It also should allow better hemostasis secondary to ease of switching the laser to hemostatic settings using the foot pedal instead of requiring a laser-trained technician to input settings. The present study compares the enucleation efficiency of HoLEP (measured as g of tissue enucleated per minute of enucleation time) performed using the 120H laser platform vs the older 100-watt holmium laser platform (VersaPulse PowerSuite 100 Watt; Lumenis). Patients and Methods Patients at a single institution who underwent HoLEP for lower urinary tract symptoms or urinary retention from BPH using the new 120H laser platform were
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identified from a prospectively maintained database. Each patient was matched with 2 patients who underwent HoLEP with the single-pedal 100-watt laser, on the basis of propensity score matching with a logistic model fitted by age and preoperative transrectal ultrasonography (TRUS) prostate volume. All HoLEPs were performed by or under the supervision of a sole endourology fellowship-trained surgeon (initials withheld for anonymous review). HoLEPs in both groups were performed with similar laser settings, adjusting the power (Joules [J]) and frequency (Hertz [Hz]) for hemostasis and dissection. A setting of 40 Hz and 2 J was used for most of the enucleation. Dissection around the apex and hemostasis were done with a setting of 30 Hz and 1.5 J on the 120H laser and 20 Hz and 2 J on the 100-watt machine. The standard 3-lobe technique previously described in detail (7) was used for patients with trilobar hyperplasia, adjusting to a 2-lobe technique for patients with bilobar hyperplasia. Enucleation time was recorded for each case. With the 100-watt system, enucleation time started at the beginning of the dissection and ended after the final lobe was pushed into the bladder. Hemostasis was typically done after the final lobe was enucleated. Enucleation time with the 120H laser platform started at the beginning of the dissection and included the hemostasis performed throughout the procedure. This difference in time calculation is discussed below. A morcellator system (Lumenis) was used for all cases. Preoperative baseline characteristics of the patients included age, American Society of Anesthesiologists score, body mass index, TRUS prostate volume, and hemoglobin concentration. Operative details included total operative time, enucleation time, and total energy used. Postoperative details included hemoglobin level, weight of resected tissue, and pathologic findings. Complications were reported in both groups.
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The primary outcome for this study was the evaluation of enucleation efficiency of each laser platform, using the weight of resected prostate tissue for this calculation. Secondary outcomes included complications, need for blood transfusion, and total operative time. Basic statistics—frequency and percentage for categorical data and mean and standard deviation for continuous data—were used to summarize the data. McNemar test and conditional logistic model were used to associate predictors and cases. A P value of <.05 was considered statistically significant. All statistical analyses were performed by SAS version 9.4 software (SAS Institute Inc). Results In total, 29 patients who underwent HoLEP with the 120H platform (mean age, 69.5 years) were matched with 58 patients who underwent HoLEP with the 100-watt platform (mean age, 69.5 years) (Table 1). Both groups were similar after matching for propensity score. No significant difference was found in age, TRUS prostate volume, American Society of Anesthesiologists score, body mass index, prostate anatomy (eg, bilobar, trilobar, regrowth), prior BPH operation, prior BPH medication, or final pathologic results. Statistically significant differences were seen in total operating room (OR) time, total operating procedure time, and enucleation time (Table 2). Mean total OR time in the control group was 133.2 minutes; in the 120H platform group, it was 165.8 minutes (P=.005). Mean operating procedure time was 102.2 minutes in the control group vs 124.5 minutes in the experimental group (P=.04). Mean enucleation time was 54.98 minutes in the control group vs 68.79 minutes in the experimental group (P=.03). Mean resected weight was 46.44 g in the control group vs 58.48 g in the experimental group (P=.25). Other outcome variables showed no statistically significant difference, however. Enucleation efficiency, the primary outcome, was similar between the 2 laser platforms at 0.89 g per minute in the control group vs 0.84 g per minute in the 120H group (P=.72).
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Postoperative outcomes were also similar between the groups (Table 2). The percentage of patients who needed a blood transfusion (P=.21) and the hemoglobin decrease from preoperative to postoperative phases (P=.36) were similar. No significant change in sodium occurred, an expected result since the laser irrigant is sodium chloride. The control group had 6 minor complications (Clavien-Dindo Classification grade I or II) and 4 major complications (Clavien-Dindo grade III or IV) at 30 days. One major complication (Clavien-Dindo class III or IV) occurred in the control group at 90 days; no complications of Clavien-Dindo classes II through V were found in the 120H group. Pathologic findings were similar, with 6% of the control group having Gleason score 6 prostate cancer vs 14% of the 120H group (P=.25). Discussion HoLEP is often suggested as the gold standard for surgical treatment of BPH, especially for a large prostate (1,8). The guidelines of both the American Urological Association and the European Association of Urology list HoLEP as a preferred treatment of BPH (9,10). Recent literature on the long-term reoperation rates after HoLEP indicates that HoLEP is a durable operation with a reoperation-free rate of 95% at 10 years (11). Multiple advances have been made in HoLEP over the past several years, including the introduction of more powerful laser platforms, as well as improved morcellations (12,13). Ideally, the newer laser platform offers increased efficiency. The dual foot pedal allows the surgeon to switch easily and quickly between 2 laser settings. Theoretically, this capability allows the enucleation portion of the procedure to proceed more efficiently and with less blood loss since the surgeon does not have to wait for a laser technician to switch the settings for hemostasis. This study did not show a difference in enucleation efficiency or change in hemoglobin concentration between the 2 laser platforms: More tissue was enucleated but in a longer period. However, the
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enucleation efficiency of the experimental group may have been underestimated since hemostasis time was generally not included in the recorded enucleation time for the control group. The difference in time recording and calculation is due to technological differences between the platforms, and we acknowledge this as a potential bias of the outcomes. In the single-pedal 100-watt unit, hemostasis requires manual manipulation of the laser setting down to 1.5 J and 30 Hz, which is done at the conclusion of the case. This historically was not considered a part of the enucleation time since the tissue was already enucleated. In contrast, with the new 120H unit, its 2 foot pedals can be set at different energy levels so that 1 pedal can be at the enucleation setting of 2 J and 40 H and the other set at the hemostatic setting of 1.5 J and 30 Hz. In the later cases, hemostasis was obtained at the time it was encountered, rather than at the end of the procedure. Hence, this hemostasis time was included in the enucleation time and thus potentially influenced the overall efficiency. This cannot be corrected because of the limitations of the current data set. It should be noted, however, that in general, the time for hemostasis after enucleation with the 100-watt platform was estimated to take only an additional 30 to 90 seconds per procedure. The cost of the new 120H laser platform is approximately $175,000 on average. Compared with other BPH treatment modalities, laser prostatectomies have been cost-effective (14). The initial cost of the laser and morcellator can be great, but the procedure uses similar materials as in such urologic procedures as transurethral resection of the prostate and stone removal (8). HoLEP is associated with shorter hospital stays, which contribute to a lower cost, and it has been described as more cost-effective than transurethral resection of the prostate as a single procedure and less expensive than open surgery (8). Although the newer laser platform did not prove to be more efficient when evaluating enucleation specifically, the greater costs of the 120H laser platform possibly
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could be returned through other procedures done with the laser, such as laser lithotripsy and holmium laser ablation. In addition, the increased total energy available with the new system has not been used in our practice. We have not found a benefit of higher energy, but perhaps surgeons who enucleate at 2 J and 60 Hz may find improved efficiency with this system. Of note, an episode occurred with the 120H laser platform in which it caught fire; the machine was promptly replaced by the company. Limitations of this study include its small sample size. The patients who had HoLEP with the 100-watt platform usually did not have hemostasis time included in their enucleation times, although the hemostasis time is usually minimal. The learning curve should not be substantial with the new platform, but increased time possibly was spent getting used to the dual pedal template. More research should be done to compare the 2 systems and to compare the new laser platform with other surgical BPH treatment modalities. Conclusion The efficiency of the new 120H laser platform is comparable with the 100watt holmium laser platform in HoLEP tissue enucleation.
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References 1. van Rij S, Gilling PJ. In 2013, holmium laser enucleation of the prostate (HoLEP) may be the new ‘gold standard.’ Curr Urol Rep. 2012 Dec;13(6):427-32. 2. Stern K, Satyanarayan A, Funk JT. Recent advances and emerging technology in the surgical management of BPH-related voiding dysfunction. Curr Bladder Dysfunct Rep. 2014 Jun;9(2):129-33. Epub 2014 Mar 1. 3. Lee MH, Yang HJ, Kim DS, Lee CH, Jeon YS. Holmium laser enucleation of the prostate is effective in the treatment of symptomatic benign prostatic hyperplasia of any size including a small prostate. Korean J Urol. 2014 Nov;55(11):737-41. Epub 2014 Nov 4. 4. Gilling PJ, Cass CB, Cresswell MD, Fraundorfer MR. Holmium laser resection of the prostate: preliminary results of a new method for the treatment of benign prostatic hyperplasia. Urology. 1996 Jan;47(1):48-51. 5. Elzayat EA, Habib EI, Elhilali MM. Holmium laser enucleation of the prostate: a size-independent new “gold standard.” Urology. 2005 Nov;66(5 Suppl):108-13. 6. Elshal AM, Mekkawy R, Laymon M, El-Assmy A, El-Nahas AR. Towards optimizing prostate tissue retrieval following holmium laser enucleation of the prostate (HoLEP): assessment of two morcellators and review of the literature. Can Urol Assoc J. 2015 Sep-Oct;9(9-10):E618-25. 7. Humphreys MR, Miller NL, Handa SE, Terry C, Munch LC, Lingeman JE. Holmium laser enucleation of the prostate: outcomes independent of prostate size? J Urol. 2008 Dec;180(6):2431-5. Epub 2008 Oct 19. 8. Vincent MW, Gilling PJ. HoLEP has come of age. World J Urol. 2015 Apr;33(4):487-93. Epub 2014 Nov 22.
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9. American Urological Association. AUA guidelines & policies [Internet]. Linthicum (MD): American Urological Association. [cited 2016 May 20]. Available from: https://www.auanet.org/education/aua-guidelines.cfm. 10. European Association of Urology. EAU guidelines [Internet]. The Netherlands: European Association of Urology. c2016 [cited 2016 May 20]. Available from: https://uroweb.org/guidelines/. 11. Elkoushy MA, Elshal AM, Elhilali MM. Reoperation after holmium laser enucleation of the prostate for management of benign prostatic hyperplasia: assessment of risk factors with time to event analysis. J Endourol. 2015 Jul;29(7):797-804. Epub 2015 Apr 2. 12. Lumenis: energy to healthcare. Lumenis pulse 120H [Internet]. San Jose (CA): Lumenis. c2016 [cited 2016 May 20]. Available from: http://www.lumenis.com/Solutions/Surgical/lumenis-pulse-120H. 13. El Tayeb MM, Borofsky MS, Paonessa JE, Lingeman JE. Wolf Piranha versus lumenis versacut prostate morcellation devices: a prospective randomized trial. J Urol. 2016 Feb;195(2):413-7. Epub 2015 Aug 22. 14. Wilson LC, Gilling PJ, Williams A, Kennett KM, Frampton CM, Westenberg AM, et al. A randomised trial comparing holmium laser enucleation versus transurethral resection in the treatment of prostates larger than 40 grams: results at 2 years. Eur Urol. 2006 Sep;50(3):569-73. Epub 2006 May 2.
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Table 1. Baseline Patient Characteristics Laser Platform Group Variablea
100-Watt (n=58)
120H (n=29)
OR (95% CI)
P Value
Age, y
69.5 (9.10)
69.5 (9.45)
1.078 (0.560-2.075)
.82
TRUS prostate volume, cm3
87.8 (54.78)
94.0 (42.22)
1.002 (0.994-1.011)
.59
ASA score
2.37 (0.56)
2.28 (0.70)
0.716 (0.306-1.678)
.44
BMI
27.3 (4.35)
27.9 (5.37)
1.033 (0.935-1.141)
.52
0.629 (0.269-1.473)
.29
BPH, No. (%) Bilobar
23 (43)
17 (59)
Trilobar
29 (54)
12 (41)
4 (8)
2 (11)
1.686 (0.232-12.232)
.61
Prior BPH medication, No. (%)
36 (80)
23 (92)
4.541 (0.534-38.656)
.17
Urinary catheter, No. (%)
14 (29)
9 (43)
2.393 (0.670-8.542)
.18
Prior BPH operation, No. (%)
Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; BPH, benign prostatic hyperplasia; OR, odds ratio; TRUS, transrectal ultrasonography. a
Categorical data are presented as frequency and percentage; continuous data are presented as mean and
standard deviation.
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-13Table 2. Intraoperative and Postoperative Differences Laser Platform Group Outcomesa
100-Watt (n=58)
120H (n=29)
P Value
OR
133.2 (49.02)
165.8 (41.42)
.005
OP
102.2 (46.64)
124.5 (43.50)
.04
Enucleation
54.98 (27.66)
68.79 (24.81)
.03
Morcellation
16.17 (18.32)
21.45 (19.45)
.23
Resected prostate weight, g
46.44 (39.33)
58.48 (34.29)
.17
Preop Hb, g/dL
14.03 (1.58)
13.93 (1.61)
.79
Postop Hb, g/dL
12.34 (1.69)
12.29 (1.93)
.92
Change in Hb, g/dL
1.92 (1.32)
1.64 (1.12)
.36
Preop sodium, mmol/L
139.1 (3.20)
139.5 (2.34)
.55
Postop sodium, mmol/L
138 (2.55)
138.8 (3.44)
.25
Change in sodium, mmol/L
1.16 (3.05)
2.5 (2.22)
.11
Transfusion needed, No. (%)
3 (6)
0 (0)
.21
Gleason score 6, No. (%)
3 (6)
4 (14)
.16
Time, min
Abbreviations: Hb, hemoglobin; OP, operative; OR, operating room; postop, postoperative; preop, preoperative. a
Values are presented as mean (SD) unless specified otherwise.
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S0090-4295(16)30968-2 http://dx.doi.org/doi: 10.1016/j.urology.2016.12.022 URL 20200
To appear in:
Urology
Received date: Accepted date:
28-9-2016 14-12-2016
Please cite this article as: Karen L. Stern, Sean B. McAdams, Stephen S. Cha, Haidar M. AbdulMuhsin, Mitchell R. Humphreys, A New Laser Platform for Holmium Laser Enucleation of the Prostate: Does the Lumenis Pulse 120H Laser Platform Improve Enucleation Efficiency?, Urology (2016), http://dx.doi.org/doi: 10.1016/j.urology.2016.12.022. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
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[Category: Prostatic Diseases and Male Voiding Dysfunction] A New Laser Platform for Holmium Laser Enucleation of the Prostate: Does the Lumenis Pulse 120H Laser Platforma Improve Enucleation Efficiency? Karen L. Stern, MD Sean B. McAdams, MD Stephen S. Cha Haidar M. Abdul-Muhsin, MB, ChB Mitchell R. Humphreys, MD
Author Affiliations: Department of Urology (Drs Stern, McAdams, Abdul-Muhsin, and Humphreys), Mayo Clinic Hospital, Phoenix, Arizona, and Biostatistics (Mr Cha), Mayo Clinic, Scottsdale, Arizona. a
Mayo Clinic does not endorse specific products or services included in this
article. Reprints: Mitchell R. Humphreys, MD, Department of Urology, Mayo Clinic Hospital, 5777 E Mayo Blvd, Phoenix, AZ 85054 ([email protected]). Presented in abstract form at the 33rd World Congress of the Endourology and SWL, London, United Kingdom, October 1-4, 2015. Keywords: benign prostatic hyperplasia; holmium; laser; obstruction; prostate Acknowledgment: The authors did not receive any financial support. Research Support and Conflict of Interest: The authors did not receive any research support. No competing financial interests exist. Text word count: 1,745 Abstract word count: 247 No. of tables: 2 No. of figures: 0
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Running title: Enucleation Efficiency in HoLEP Publisher: To expedite proof approval, send proof via email to [email protected]. ©2016 Mayo Foundation for Medical Education and Research Abstract Objectives: To determine whether the recently introduced Lumenis Pulse 120H laser platform, which offers a dual-pedal footswitch and preset energy modes to easily switch among laser settings, facilitates a more efficient process in holmium laser enucleation of the prostate (HoLEP) for surgical treatment of benign prostatic hyperplasia. Methods: Patients at a single institution who underwent HoLEP with the new Lumenis Pulse 120H laser platform were matched 1:2 with patients who underwent the procedure with the previously used 100-watt VersaPulse single-pedal laser platform. Matching was performed by using propensity scores calculated by a logistic model that considered preoperative transrectal ultrasound prostate volume and patient age. The primary outcome was enucleation efficiency of each platform, determined by the weight of prostate tissue resected and enucleation time. The McNemar test and a conditional logistic model were used to associate predictors and cases. Results: Twenty-nine patients who underwent HoLEP with the Lumenis Pulse 120H platform were matched with 58 patients who underwent the procedure with the 100-watt platform. We observed statistically significant differences in operating room total time, procedure time, and enucleation time. Other perioperative and postoperative outcomes were comparable between the 2 groups. Enucleation efficiency was similar between the 2 laser platforms (0.89 g per minute in the control group vs 0.84 g per minute in the Lumenis Pulse 120H group). Conclusions: The efficiency of the new Lumenis Pulse 120H laser platform is comparable to the 100-watt VersaPulse laser platform in HoLEP when comparing grams of tissue enucleated per minute.
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Abbreviations BPH, benign prostatic hyperplasia HoLEP, holmium laser enucleation of the prostate OR, operating room TRUS, transrectal ultrasonography
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Introduction Benign prostatic hyperplasia (BPH) affects approximately 50% of men older than 50 years and 88% of men age 80 through 89 years, often leading to decreased quality of life and ultimately requiring treatment (1,2). Holmium laser enucleation of the prostate (HoLEP) has been suggested as the gold standard for surgical treatment for BPH (1,3). First described in 1996 by Gilling et al (4), HoLEP has been shown to benefit men with obstructive symptoms independent of prostate size and to have durable results (1,4,5). Multiple technological and procedural advances have been made over the past several years to improve the efficacy and efficiency of the procedure, including new morcellators, compatibility with multiple scope manufacturers, alterations in technique to allow more persons to learn the technique, and the recent delivery of a new 120H laser platform (Lumenis Pulse; Lumenis Ltd) (6). The platform allows for preset energy modes, and a dual foot pedal allows the surgeon to switch between 2 laser settings easily. Typically, lower energy settings are used for hemostasis and near the prostatic apex; higher energy settings are used for most of the enucleation. Theoretically, the dual foot pedal should allow the enucleation portion of the procedure to proceed more efficiently. It also should allow better hemostasis secondary to ease of switching the laser to hemostatic settings using the foot pedal instead of requiring a laser-trained technician to input settings. The present study compares the enucleation efficiency of HoLEP (measured as g of tissue enucleated per minute of enucleation time) performed using the 120H laser platform vs the older 100-watt holmium laser platform (VersaPulse PowerSuite 100 Watt; Lumenis). Patients and Methods Patients at a single institution who underwent HoLEP for lower urinary tract symptoms or urinary retention from BPH using the new 120H laser platform were
Page 4 of 13
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identified from a prospectively maintained database. Each patient was matched with 2 patients who underwent HoLEP with the single-pedal 100-watt laser, on the basis of propensity score matching with a logistic model fitted by age and preoperative transrectal ultrasonography (TRUS) prostate volume. All HoLEPs were performed by or under the supervision of a sole endourology fellowship-trained surgeon (initials withheld for anonymous review). HoLEPs in both groups were performed with similar laser settings, adjusting the power (Joules [J]) and frequency (Hertz [Hz]) for hemostasis and dissection. A setting of 40 Hz and 2 J was used for most of the enucleation. Dissection around the apex and hemostasis were done with a setting of 30 Hz and 1.5 J on the 120H laser and 20 Hz and 2 J on the 100-watt machine. The standard 3-lobe technique previously described in detail (7) was used for patients with trilobar hyperplasia, adjusting to a 2-lobe technique for patients with bilobar hyperplasia. Enucleation time was recorded for each case. With the 100-watt system, enucleation time started at the beginning of the dissection and ended after the final lobe was pushed into the bladder. Hemostasis was typically done after the final lobe was enucleated. Enucleation time with the 120H laser platform started at the beginning of the dissection and included the hemostasis performed throughout the procedure. This difference in time calculation is discussed below. A morcellator system (Lumenis) was used for all cases. Preoperative baseline characteristics of the patients included age, American Society of Anesthesiologists score, body mass index, TRUS prostate volume, and hemoglobin concentration. Operative details included total operative time, enucleation time, and total energy used. Postoperative details included hemoglobin level, weight of resected tissue, and pathologic findings. Complications were reported in both groups.
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The primary outcome for this study was the evaluation of enucleation efficiency of each laser platform, using the weight of resected prostate tissue for this calculation. Secondary outcomes included complications, need for blood transfusion, and total operative time. Basic statistics—frequency and percentage for categorical data and mean and standard deviation for continuous data—were used to summarize the data. McNemar test and conditional logistic model were used to associate predictors and cases. A P value of <.05 was considered statistically significant. All statistical analyses were performed by SAS version 9.4 software (SAS Institute Inc). Results In total, 29 patients who underwent HoLEP with the 120H platform (mean age, 69.5 years) were matched with 58 patients who underwent HoLEP with the 100-watt platform (mean age, 69.5 years) (Table 1). Both groups were similar after matching for propensity score. No significant difference was found in age, TRUS prostate volume, American Society of Anesthesiologists score, body mass index, prostate anatomy (eg, bilobar, trilobar, regrowth), prior BPH operation, prior BPH medication, or final pathologic results. Statistically significant differences were seen in total operating room (OR) time, total operating procedure time, and enucleation time (Table 2). Mean total OR time in the control group was 133.2 minutes; in the 120H platform group, it was 165.8 minutes (P=.005). Mean operating procedure time was 102.2 minutes in the control group vs 124.5 minutes in the experimental group (P=.04). Mean enucleation time was 54.98 minutes in the control group vs 68.79 minutes in the experimental group (P=.03). Mean resected weight was 46.44 g in the control group vs 58.48 g in the experimental group (P=.25). Other outcome variables showed no statistically significant difference, however. Enucleation efficiency, the primary outcome, was similar between the 2 laser platforms at 0.89 g per minute in the control group vs 0.84 g per minute in the 120H group (P=.72).
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Postoperative outcomes were also similar between the groups (Table 2). The percentage of patients who needed a blood transfusion (P=.21) and the hemoglobin decrease from preoperative to postoperative phases (P=.36) were similar. No significant change in sodium occurred, an expected result since the laser irrigant is sodium chloride. The control group had 6 minor complications (Clavien-Dindo Classification grade I or II) and 4 major complications (Clavien-Dindo grade III or IV) at 30 days. One major complication (Clavien-Dindo class III or IV) occurred in the control group at 90 days; no complications of Clavien-Dindo classes II through V were found in the 120H group. Pathologic findings were similar, with 6% of the control group having Gleason score 6 prostate cancer vs 14% of the 120H group (P=.25). Discussion HoLEP is often suggested as the gold standard for surgical treatment of BPH, especially for a large prostate (1,8). The guidelines of both the American Urological Association and the European Association of Urology list HoLEP as a preferred treatment of BPH (9,10). Recent literature on the long-term reoperation rates after HoLEP indicates that HoLEP is a durable operation with a reoperation-free rate of 95% at 10 years (11). Multiple advances have been made in HoLEP over the past several years, including the introduction of more powerful laser platforms, as well as improved morcellations (12,13). Ideally, the newer laser platform offers increased efficiency. The dual foot pedal allows the surgeon to switch easily and quickly between 2 laser settings. Theoretically, this capability allows the enucleation portion of the procedure to proceed more efficiently and with less blood loss since the surgeon does not have to wait for a laser technician to switch the settings for hemostasis. This study did not show a difference in enucleation efficiency or change in hemoglobin concentration between the 2 laser platforms: More tissue was enucleated but in a longer period. However, the
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enucleation efficiency of the experimental group may have been underestimated since hemostasis time was generally not included in the recorded enucleation time for the control group. The difference in time recording and calculation is due to technological differences between the platforms, and we acknowledge this as a potential bias of the outcomes. In the single-pedal 100-watt unit, hemostasis requires manual manipulation of the laser setting down to 1.5 J and 30 Hz, which is done at the conclusion of the case. This historically was not considered a part of the enucleation time since the tissue was already enucleated. In contrast, with the new 120H unit, its 2 foot pedals can be set at different energy levels so that 1 pedal can be at the enucleation setting of 2 J and 40 H and the other set at the hemostatic setting of 1.5 J and 30 Hz. In the later cases, hemostasis was obtained at the time it was encountered, rather than at the end of the procedure. Hence, this hemostasis time was included in the enucleation time and thus potentially influenced the overall efficiency. This cannot be corrected because of the limitations of the current data set. It should be noted, however, that in general, the time for hemostasis after enucleation with the 100-watt platform was estimated to take only an additional 30 to 90 seconds per procedure. The cost of the new 120H laser platform is approximately $175,000 on average. Compared with other BPH treatment modalities, laser prostatectomies have been cost-effective (14). The initial cost of the laser and morcellator can be great, but the procedure uses similar materials as in such urologic procedures as transurethral resection of the prostate and stone removal (8). HoLEP is associated with shorter hospital stays, which contribute to a lower cost, and it has been described as more cost-effective than transurethral resection of the prostate as a single procedure and less expensive than open surgery (8). Although the newer laser platform did not prove to be more efficient when evaluating enucleation specifically, the greater costs of the 120H laser platform possibly
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could be returned through other procedures done with the laser, such as laser lithotripsy and holmium laser ablation. In addition, the increased total energy available with the new system has not been used in our practice. We have not found a benefit of higher energy, but perhaps surgeons who enucleate at 2 J and 60 Hz may find improved efficiency with this system. Of note, an episode occurred with the 120H laser platform in which it caught fire; the machine was promptly replaced by the company. Limitations of this study include its small sample size. The patients who had HoLEP with the 100-watt platform usually did not have hemostasis time included in their enucleation times, although the hemostasis time is usually minimal. The learning curve should not be substantial with the new platform, but increased time possibly was spent getting used to the dual pedal template. More research should be done to compare the 2 systems and to compare the new laser platform with other surgical BPH treatment modalities. Conclusion The efficiency of the new 120H laser platform is comparable with the 100watt holmium laser platform in HoLEP tissue enucleation.
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References 1. van Rij S, Gilling PJ. In 2013, holmium laser enucleation of the prostate (HoLEP) may be the new ‘gold standard.’ Curr Urol Rep. 2012 Dec;13(6):427-32. 2. Stern K, Satyanarayan A, Funk JT. Recent advances and emerging technology in the surgical management of BPH-related voiding dysfunction. Curr Bladder Dysfunct Rep. 2014 Jun;9(2):129-33. Epub 2014 Mar 1. 3. Lee MH, Yang HJ, Kim DS, Lee CH, Jeon YS. Holmium laser enucleation of the prostate is effective in the treatment of symptomatic benign prostatic hyperplasia of any size including a small prostate. Korean J Urol. 2014 Nov;55(11):737-41. Epub 2014 Nov 4. 4. Gilling PJ, Cass CB, Cresswell MD, Fraundorfer MR. Holmium laser resection of the prostate: preliminary results of a new method for the treatment of benign prostatic hyperplasia. Urology. 1996 Jan;47(1):48-51. 5. Elzayat EA, Habib EI, Elhilali MM. Holmium laser enucleation of the prostate: a size-independent new “gold standard.” Urology. 2005 Nov;66(5 Suppl):108-13. 6. Elshal AM, Mekkawy R, Laymon M, El-Assmy A, El-Nahas AR. Towards optimizing prostate tissue retrieval following holmium laser enucleation of the prostate (HoLEP): assessment of two morcellators and review of the literature. Can Urol Assoc J. 2015 Sep-Oct;9(9-10):E618-25. 7. Humphreys MR, Miller NL, Handa SE, Terry C, Munch LC, Lingeman JE. Holmium laser enucleation of the prostate: outcomes independent of prostate size? J Urol. 2008 Dec;180(6):2431-5. Epub 2008 Oct 19. 8. Vincent MW, Gilling PJ. HoLEP has come of age. World J Urol. 2015 Apr;33(4):487-93. Epub 2014 Nov 22.
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9. American Urological Association. AUA guidelines & policies [Internet]. Linthicum (MD): American Urological Association. [cited 2016 May 20]. Available from: https://www.auanet.org/education/aua-guidelines.cfm. 10. European Association of Urology. EAU guidelines [Internet]. The Netherlands: European Association of Urology. c2016 [cited 2016 May 20]. Available from: https://uroweb.org/guidelines/. 11. Elkoushy MA, Elshal AM, Elhilali MM. Reoperation after holmium laser enucleation of the prostate for management of benign prostatic hyperplasia: assessment of risk factors with time to event analysis. J Endourol. 2015 Jul;29(7):797-804. Epub 2015 Apr 2. 12. Lumenis: energy to healthcare. Lumenis pulse 120H [Internet]. San Jose (CA): Lumenis. c2016 [cited 2016 May 20]. Available from: http://www.lumenis.com/Solutions/Surgical/lumenis-pulse-120H. 13. El Tayeb MM, Borofsky MS, Paonessa JE, Lingeman JE. Wolf Piranha versus lumenis versacut prostate morcellation devices: a prospective randomized trial. J Urol. 2016 Feb;195(2):413-7. Epub 2015 Aug 22. 14. Wilson LC, Gilling PJ, Williams A, Kennett KM, Frampton CM, Westenberg AM, et al. A randomised trial comparing holmium laser enucleation versus transurethral resection in the treatment of prostates larger than 40 grams: results at 2 years. Eur Urol. 2006 Sep;50(3):569-73. Epub 2006 May 2.
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Table 1. Baseline Patient Characteristics Laser Platform Group Variablea
100-Watt (n=58)
120H (n=29)
OR (95% CI)
P Value
Age, y
69.5 (9.10)
69.5 (9.45)
1.078 (0.560-2.075)
.82
TRUS prostate volume, cm3
87.8 (54.78)
94.0 (42.22)
1.002 (0.994-1.011)
.59
ASA score
2.37 (0.56)
2.28 (0.70)
0.716 (0.306-1.678)
.44
BMI
27.3 (4.35)
27.9 (5.37)
1.033 (0.935-1.141)
.52
0.629 (0.269-1.473)
.29
BPH, No. (%) Bilobar
23 (43)
17 (59)
Trilobar
29 (54)
12 (41)
4 (8)
2 (11)
1.686 (0.232-12.232)
.61
Prior BPH medication, No. (%)
36 (80)
23 (92)
4.541 (0.534-38.656)
.17
Urinary catheter, No. (%)
14 (29)
9 (43)
2.393 (0.670-8.542)
.18
Prior BPH operation, No. (%)
Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; BPH, benign prostatic hyperplasia; OR, odds ratio; TRUS, transrectal ultrasonography. a
Categorical data are presented as frequency and percentage; continuous data are presented as mean and
standard deviation.
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-13Table 2. Intraoperative and Postoperative Differences Laser Platform Group Outcomesa
100-Watt (n=58)
120H (n=29)
P Value
OR
133.2 (49.02)
165.8 (41.42)
.005
OP
102.2 (46.64)
124.5 (43.50)
.04
Enucleation
54.98 (27.66)
68.79 (24.81)
.03
Morcellation
16.17 (18.32)
21.45 (19.45)
.23
Resected prostate weight, g
46.44 (39.33)
58.48 (34.29)
.17
Preop Hb, g/dL
14.03 (1.58)
13.93 (1.61)
.79
Postop Hb, g/dL
12.34 (1.69)
12.29 (1.93)
.92
Change in Hb, g/dL
1.92 (1.32)
1.64 (1.12)
.36
Preop sodium, mmol/L
139.1 (3.20)
139.5 (2.34)
.55
Postop sodium, mmol/L
138 (2.55)
138.8 (3.44)
.25
Change in sodium, mmol/L
1.16 (3.05)
2.5 (2.22)
.11
Transfusion needed, No. (%)
3 (6)
0 (0)
.21
Gleason score 6, No. (%)
3 (6)
4 (14)
.16
Time, min
Abbreviations: Hb, hemoglobin; OP, operative; OR, operating room; postop, postoperative; preop, preoperative. a
Values are presented as mean (SD) unless specified otherwise.
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