Holmium laser enucleation of the prostate can be taught: the first learning experience

Transcription

1 Blackwell Science, LtdOxford, UK BJUBJU International BJU International 909December LEARNING HoLEP A. EL-HAKIM and M.M. ELHILALI /j x Original Article863869BEES SGML BJU International (2002), 90, doi: /j x Holmium laser enucleation of the prostate can be taught: the first learning experience A. EL-HAKIM and M.M. ELHILALI Department of Urology, McGill University Faculty of Medicine, Montreal, Quebec, Canada Objective To present the initial experience of a senior urology resident with holmium laser enucleation of the prostate (HoLEP) and to address the difficulties encountered while learning this technique, describing the detailed operative technique and pitfalls. Patients and methods Between July and August 2001, 27 patients were treated using HoLEP administered by one senior urology resident (A.H.) under the supervision of an experienced urologist (M.M.E.). Patients were assessed before and 1 month after HoLEP by the International Prostate Symptom Score (IPSS), the associated quality-of-life (QoL) score, and measurements of maximum urinary flow rate (Q max ) and postvoid residual urine (PVR) volume. The prostate volume was measured before HoLEP using transrectal ultrasonography. The 27 patients were compared retrospectively with 118 who underwent HoLEP by the supervising urologist. Each of the 27 procedures was taped and reviewed. Results The mean (range) prostate size was 54.8 (21 122) ml (A.H.) and 61.7 ( ) ml (M.M.E.). The mean operative duration was 98 (50 175) min and the mean enucleation time 68 (29 108) min. The improvements in IPSS, QoL score, Q max and PVR were highly significant (P < 0.001), with mean values before and after HoLEP of 16.8 and 8.2, 3.1 and 1.4, 7.7 and 20.8 ml/s, and 232 and 41.3 ml, respectively. Of the 27 patients, 23 (85%) were catheter-free on the first day after HoLEP; the mean hospital stay was 1.8 days. All these results were comparable with the results of 118 patients treated by M.M.E. The two most difficult technical steps identified were the initial apical enucleation and the incision of the remaining antero-apical mucosal attachment of the lateral lobes. The operator became adept with the HoLEP technique after a mean of 20 patients. Conclusion HoLEP can be learnt but requires longer training than standard transurethral resection. Extensive experience with transurethral surgery and the supervision of an experienced urologist are prerequisites for success. Keywords lasers, holmium, benign prostatic hyperplasia, training Introduction Accepted for publication 18 September 2002 The use of the holmium:yag laser for treating BPH has developed substantially over the last decade. The Ho:YAG laser was initially used as a vaporization tool for treating BPH [1,2]. In 1994, Gilling et al. [3,4] then developed a new concept of resection (holmium laser resection of the prostate) and later a true enucleation of the prostatic adenoma (HoLEP) [5,6]. Currently the Ho:YAG laser offers a revolutionary way of treating BPH; its wavelength (2140 nm) is highly absorbed in a fluid environment, with a depth of tissue penetration of only 0.4 mm. It can be used to cut tissue by vaporization and coagulate blood vessels simultaneously at a depth of 1 2 mm, generating minimal histological tissue damage [7]. These intrinsic properties of the laser combined with the enucleation concept gives HoLEP an advantage over TURP in several aspects [8], i.e. decreased bleeding, decreased hospitalization, catheter time and bladder irrigation, no prostate size limitation [9] and no TUR syndrome. Consequently HoLEP has aroused a great deal of interest in the urological community, and efforts to learn and adopt this promising technique are being made. One of the major disadvantages is the perception that HoLEP is a difficult procedure to learn; it has been estimated that about 20 cases are required to achieve basic competence in the procedure [9,10] but there is no published study that has addressed specifically the learning and teaching issues. In addition to the difficulty inherent in this technique, the operative techniques described to date are concise and lack pertinent operative details that are of utmost importance, especially for the novice surgeon and resident [6,11]. We present the first teaching experience and a comprehensive technical description of HoLEP BJU International 863

2 864 A. EL-HAKIM and M.M. ELHILALI Patients and methods A senior urology resident (A.H.) watched ª 10 HoLEP procedures and participated initially in the enucleation during seven cases. When he was judged to be reasonably confident with the technical dynamics, a prospective study was designed to assess his progress in learning HoLEP. Between July and August 2001, 27 consecutive patients with symptomatic BPH were managed by HoLEP using a high-powered holmium laser (100 W) and tissue morcellation by the resident (A.H.), under the supervision of an experienced urologist (M.M.E.). Patients were assessed before and 1 month after HoLEP using the IPSS, the associated Quality-of-Life score (QoL), and measurements of the maximum urinary flow rate (Q max ), postvoid residual urine (PVR) volume, routine serum biochemical and haematological variables, and PSA. Prostate volume was measured using TRUS and urine samples cultured. Data were collected during HoLEP, i.e. the total operative duration, enucleation time, morcellation time, and the total amount of energy used. The total duration was defined as the interval between introducing the resectoscope and inserting the catheter. The time to catheter removal, duration of hospital stay, the need for bladder irrigation, and the type (intermittent vs continuous) and duration of bladder irrigation, if needed, were also recorded. Any decrease in serum sodium and haemoglobin after HoLEP was noted. The morcellated specimen was weighed and all pathology reports reviewed to record the subtypes of hyperplasia (nodular, glandular, fibromuscular) and components of prostatitis. Urine and blood samples were cultured after HoLEP if the patient s temperature was > 38 C. After 1 month, in addition to the variables assessed, all patients were questioned about stress and urge incontinence, haematuria and other relevant information. These 27 patients were compared retrospectively with 118 who underwent HoLEP by the supervising urologist (M.M.E) [8]. Each of the 27 procedures was taped and reviewed, and technical points highlighted. Technique Some of the technical surgical aspects adopted at our institution are presented, with several modifications that could facilitate HoLEP and render it a comprehensive and reproducible method. The fully detailed description of the technique is submitted jointly with the Indiana group. The technical points detailed herein were thought to be helpful during the overall learning and teaching experience, acquired at our institution for > 300 HoLEP procedures. The equipment needed is: a Ho:YAG laser ( W); a 550 mm end-firing laser fibre; a modified continuous-flow resectoscope with distal bridge; a 7 F catheter with proximal valve to stabilize the fibre; a rigid indirect nephroscope; a tissue morcellator; and a video system. For further details, see Fong and Elhilali, this issue, p Three-lobe technique This technique involves enucleating the median lobe initially, followed by the lateral lobes; it is applicable whenever there is a significantly large and well-defined median lobe. (i) The incisions at the 5 and 7 o clock positions (Fig. 1a); these incisions are located lateral to the median lobe, extending from a point distal to the ureteric orifices to each side of the verumontanum. They are started at the bladder neck and deepened to the level of the surgical capsule. The tip of the resectoscope must be kept pointing downward in the groove created between the median and the lateral lobe. The surgeon should avoid deviating laterally and incising the inferior aspect of the lateral lobe, a common initial mistake. (ii) Median lobe enucleation (Fig. 1b); the incisions at the 5 and 7 o clock positions are joined distally in front of the verumontanum, and once the plane of enucleation is identified, the tip of the scope is pushed beneath the distal aspect of the median lobe. The adenoma is enucleated retrogradely toward the bladder neck, comprising a combination of sharp dissection (incising with a soft sweeping movement) and blunt dissection (torque movement with the tip of the resectoscope). Care must be taken to avoid undermining the trigone. For better orientation, the surgeon should work back and forth from one lateral incision to the other, keeping the same depth of dissection. Once the median lobe is lifted almost completely, a helpful manoeuvre to detach it safely from the bladder neck is to shave the remaining ridge of tissue in a medial direction, starting laterally from the proximal end of the 5 or 7 o clock incision. (iii) Lateral lobe, inferior enucleation. One critical point of the surgery is to develop the proper plane at the apical aspect of the adenoma off the striated sphincter. The latter is identified distal to the verumontanum. The distal end of the 5 or 7 o clock incision is carried laterally beneath the apex of the lateral lobe, remaining inside the sphincter. The small space created should allow the tip of the resectoscope below the adenoma (Fig. 1c). This is accomplished by a combination of small cutting and blunt dissecting movements. A common mistake at this level is to avoid the sphincter and not be deep enough to the level of the capsule. At this point, the apical incision is carried circumferentially toward the 3 or 9 o clock positions, detaching the lower aspect of the apex from the inner

3 LEARNING HoLEP 865 a e b f c g d Fig. 1. The stages of HoLEP in the three-lobe technique. 5 o clock incision: thinned capsule (arrow). b, Median lobe enucleation: the 5 and 7 o clock incisions are joined in a retrograde manner. c, Apical dissection: the adenoma (black arrow) is enucleated off the inner surface of the sphincter (arrowhead); capsule (white arrow). d, Interior enucleation: the lateral lobe (arrow) is enucleated off the capsule (arrow head). e, 12 o clock incision. f, Superior enucleation. g, Superiorapical attachment incision: the right lateral lobe (white arrow) remains attached by a thin mucosal bridge (black arrow); sphincter (arrowhead).

4 866 A. EL-HAKIM and M.M. ELHILALI surface of the sphincter, by rotating the sheath progressively up to 90 (clockwise on the right and anticlockwise on the left), with the camera adapter always being held stationary and perpendicular to the floor. The laser fibre should always point to the capsular side. The enucleation then progresses in retrogradely to the bladder neck (Fig. 1d). It is important not to over-resect in a deep hole but to conserve the full range of motion of the resectoscope within the predefined boundaries. We recommend the complete enucleation of one lateral lobe at a time; it is very important to maintain a three-dimensional orientation even though operating with twodimensional vision. (iv) The incision at the 12 o clock position (Fig. 1e). One anterior incision is made at the 12 o clock position from the bladder neck to the level of the verumontanum. This is deepened down to the capsule, involving a 180 rotation of the sheath. Two difficulties are encountered; recognising the adequate depth and the length of the incision. These dimensions may seem greater than they really are for the novice surgeon; a single incision is sufficient. (v) Lateral lobe superior enucleation (Fig. 1f). The aim of this step is to join the 12 o clock incision to the previously started inferior enucleation, by extending circumferentially the 12 o clock incision around the anterior surface of the adenoma. It is important to move over the lobe and backward from the bladder neck to the verumontanum. Both upper and lower incisions need not necessarily join at this point. (vi) Supero-apical attachment incision (Fig. 1g). At this stage, the lateral lobe remains suspended distally by a strip of mucosa between the ª 2 and 12 o clock (or 10 and 12 o clock) positions. This must be incised judiciously because of the proximity of the sphincter. Withdrawing the resectoscope inside the sphincter allows a better view of the remaining attachments. These are incised either medially or laterally, and once the mucosa is divided, efforts should be made to move over the apex and forward to the bladder neck. A frequent mistake is to leave behind antero-apical tissue that may be difficult to trim or evaporate at the end. All three lobes are then placed in the bladder and morcellated. Two-lobe technique This is a modification of the three-lobe technique and is suitable whenever there is no, or only a small, median lobe. Occasionally the median lobe has ill-defined borders and seems to be fused with the lateral lobes; in this case a two-lobe technique is preferred. One initial incision is required at the 5 or 7 o clock position. The lateral lobe enucleation is similar on the side of the incision. The small median lobe is then enucleated along with the remaining lateral lobe. Tissue morcellation A standard tissue morcellator with reciprocating blades is introduced through the offset of a 27 F nephroscope that has a single irrigation channel, or using an adapted offset lens through the resectoscope sheath, which is less convenient. The morcellation is best achieved in the prostatic fossa, which significantly decreases the chance of bladder injury. Normal saline is used throughout the procedure and frusemide administered (20 mg/h of enucleation, intravenously), which almost always coincides with the end of the enucleation. In patients with larger glands repeated doses of frusemide may be required to avoid fluid overload. A 20 F two-way catheter is inserted and connected to straight drainage unless the degree of haematuria requires bladder irrigation. Intermittent bladder irrigation is delivered through a Y-connector without changing the catheter. In the rare event where haematuria persists despite intermittent irrigation, continuous irrigation is instituted using a three-way catheter. Results For the first 15 patients, the resident performed on average 85% of the operation and the attending staff intervened whenever difficulty arose. The last 12 patients were managed completely by the resident and the staff urologist did not intervene. The patients characteristics are shown in Table 1; there was a slight difference in mean prostate size but all other variables were similar. The overall mean (range) PSA level was 3.30 ( ) ng/ml. All patients had symptomatic BPH and three (11%) had re-growth after initial TURP. One patient (4%) had bladder stones which were treated in the same setting. Four patients (15%) were taking anticoagulant but the warfarin was stopped 4 days before HoLEP. One patient had Von-Willebrand disease and was treated in hospital with desmopressin for 3 days before surgery. Three patients (11%) were admitted 1 day before surgery for medical re-assessment. One patient in retention with an indwelling catheter had a UTI and was treated with oral ciprofloxacin. Two patients (7%) were in complete retention; one was managed with intermittent catheterization and one with an indwelling catheter. The operative data are also shown in Table 1; the overall mean (range) operative duration was 98 (50 175) min and the weight of the specimen retrieved 23.3 (9 74) g. The mean morcellation efficacy was ª 2.6 g/min. Comparison between the first 15 and the last 12 patients showed

5 LEARNING HoLEP 867 Table 1 The baseline characteristics of the patients and the results during and after surgery for the two groups of patients treated by the resident (A.H.) or experienced urologist (M.M.E.) Variable A.H. M.M.E. No. of patients Baseline Mean (range): patient age, years 66.9 (57 82) 68.3 (52 89) prostate size, ml 54.8 (21 122) 61.7 (21 172) IPSS 16.8 (3 32) 17 (5 35) QoL score 3.1 (0 6) 3.3 (0 6) Q max, ml/s 7.7 (0 16.9) 8.2 (2 18) PVR, ml 232 (0 616) 181 (0 777) Operative duration, min 98 (50 175) 115 (35 255) energy used, J 146 ( ) 187 (18 431) enucleation time, min 68 (29 108) NA morcellation time, min 9 (2 22) NA weight of specimen, g 23.3 (9 74) 24.7 (1 114) After HoLEP, n (%) Bladder irrigation: none 20 (74) 92 (78) intermittent (< 24 h) 6 (22) NA continuous (< 24 h) 1 (4) 18 (15) catheterization (< 24 h) 23 (85) 95 (85) catheterization (> 48 h) 2 (7) NA Mean (range): hospitalization, days 1.8 (1 8) 1.7 (1 25) decrease in Na +, mmol/l 2.6 (0 7) 1.7 (0 7) decrease in haemoglobin, 10.2 (0 30) 11.6 (0 73) g/l One-month follow-up No. of patients Mean (range): IPSS 8.2 (1 27) 8.4 (2 27) QoL score 1.4 (0 5) 1.8 (0 6) Q max, ml/s 20.8 ( ) 20.7 (6 43) PVR, ml 41.3 (0 199) 43.4 (0 200) no significant differences in patient characteristics or operative variables. The results after HoLEP are also shown in Table 1; three quarters of the patients required no bladder irrigation and 85% were sent home catheter-free < 24 h after HoLEP. Seven patients (25%) required bladder irrigation, six of whom (22%) were on intermittent and only one (4%) on continuous irrigation. The mean hospital stay was 1.8 days, the mean decrease in haemoglobin 10.2 (0 30) g/l, and the mean decrease in serum sodium 2.6 (0 7) mmol/l. No patient developed TUR syndrome and none required a blood transfusion. One patient with chronic active hepatitis B required platelet transfusion for thrombocytopenia secondary to splenomegaly, and developed a post-obstructive diuresis, which required catheterization for 6 days and a hospital stay of 8 days. One patient (4%) was re-catheterized on the first day and the catheter removed successfully 15 days after HoLEP. Before HoLEP, this patient had a Q max of 8.7 ml/s, a PVR of 275 ml and a prostate volume of 35 ml. No attempt was made to remove his catheter earlier because of clinical scheduling delays. Two patients had their catheter removed 2 days after HoLEP. No patient developed a UTI but four (15%) had a transient fever of > 38 C with negative urine and blood cultures. No patient had cardiovascular, pulmonary, or thrombo-embolic complications. The final pathology reports showed no prostate adenocarcinoma, and a variety of hyperplasia subtypes, i.e. 12 nodular, five glandular, four glandular and fibromuscular, three nodular with chronic prostatitis, and two glandular and fibromuscular with chronic prostatitis. The assessment at 1 month after HoLEP is also shown in Table 1; data from 23 of the 27 patients (85%) were available at 1 month. There was a dramatic improvement in all variables assessed, i.e. a 205% decrease in the mean IPSS, a 221% decrease in the mean QoL score, a 270% increase in mean Q max and a 562% decrease in mean PVR (Table 1). One patient (4%) had mixed urinary incontinence associated with irritative symptoms. These symptoms were already present since a previous TURP 9 years earlier. He was started on oral tolterodine (intolerant to oxybutynin). Three additional patients (11%) had irritative symptoms and were treated expectantly. One patient developed a urethral stricture requiring urethrotomy at 4 months. No patient had sustained haematuria, including those who resumed anticoagulation. All patients were satisfied (QoL score 0 2) except the patient with a urethral stricture and one with irritative symptoms (QoL score 5). Discussion HoLEP is an ideal way of treating BPH; the enucleation of the adenoma is an old concept used in open prostatectomy in large glands. HoLEP is suitable for any size of prostate and preserves minimal invasiveness [8,9]. The laser fibre with the resectoscope sheath form a unit that could be compared to the surgeon s finger enucleating the adenoma. The working plane is the same and the movements are similar (circumferential and sweeping). The advantage of this technique is direct-vision monitoring and simultaneous coagulation of virtually all bleeding vessels encountered. Moreover, the dissection could be sharp or blunt; about half of the enucleation is blunt. The movements of the resectoscope sheath around the adenoma configure to its shape; the larger the adenoma the wider are the angles. Patients with hip mobility problems secondary to degenerative disease, who cannot be placed in an adequate lithotomy position, are a relative contraindication for HoLEP. Throughout the operation the surgeon should mentally reproduce the three-dimensional configuration of the adenoma, according to the preoperative evaluation and intra-

6 868 A. EL-HAKIM and M.M. ELHILALI operative findings. Three-dimensional awareness and hand-eye coordination are crucial in this process, similar to laparoscopic surgery. Visibility in HoLEP, compared with standard TURP, is much better because of the bloodless field and the greater image magnification. The latter is a result of the shorter working distance in HoLEP because the tip of the fibre is only a few millimetres from the optic. In addition, the working space is smaller. This image magnification could initially cause disorientation; the wide operative field perspective is replaced by a closer view. Many efforts at reorientation could be timeconsuming and moreover, the visibility is altered when the laser is on; the fibre vibration and tissue evaporation create a blurred image. Another caveat is tissue recognition; there are three entities that need to be readily identified, i.e. the adenoma, the capsule and the plane of enucleation. The adenoma is a distinctive yellow-brown when cut, and is slightly more consistent and resistant. It is uncommon for the beginner to recognize this subtle difference. The surgical capsule is whitish, with several layers of concentric fibres. A network of vessels runs on the inner surface of the capsule and sends perforating vessels to the adenoma. The capsule gives the impression of being very thin or even perforated, which is not the case most of the time. The plane of enucleation is characterized by flimsy transverse or diagonal fibres with vessels running between the capsule and the adenoma. It is easily developed with blunt dissection and offers the least resistance. Dissecting away from the capsule results in several false planes. The holmium laser is a cutting and coagulating tool, depending on the distance and angle of the fibre from the tissue and the energy used. Varying these factors allows better haemostasis. Tissue is coagulated by aiming at the bleeding vessel from a slight distance (defocused at 1 2 mm), until the tissue blanches. Firing at an angle could also achieve haemostasis. The red laser aiming beam is useful to align precisely the fibre with its target only in the final phase of haemostasis, but not throughout the procedure, as it changes the colour perception during enucleation. We have tested various combinations of energy levels and found that the best for coagulation is 1.5 J 30 Hz = 45 W. The same energy can be used for removing small residual tissue in areas where precision is required (i.e. near the sphincter) to prevent thermal injury. A few technical points need emphasis; tissue morcellation inside the prostatic fossa significantly reduces the risk of bladder injury. There were no bladder injuries in the present patients. The indirect nephroscope used does not project the irrigation solution from small orifices at its distal extremity; rather, the water flow is distributed evenly within the nephroscope sheath. Consequently it does not push away tissue fragments and therefore avoids having to chase them with excessive suction, and risking bladder mucosal entrapment. At the end of the morcellation small round tissue fragments may persist. These beach balls are sometimes difficult to morcellate because they dislodge from the morcellator blades, but could be irrigated out or removed with the serrated loop. When they persist, incising the surface with the laser fibre renders them irregular enough for morcellation. It takes longer to learn HoLEP than TURP and the technical challenge is greater. Pre-requisites for success include extensive experience with TURP using the video camera, analytical observation of about 10 cases, and then progressively performing parts of the surgery. Smaller glands are initially easier to manage. Condensing the learning process into a short period is also important; an average of cases are needed for the trainee to feel confident. The key to success is the direct supervision of an experienced urologist; we recommend video recording the procedures so that the residents can review them alone and identify problem areas to be addressed during the next case. This is inexpensive and allows the procedure to be replayed among the resident staff. All technical pitfalls and caveats described were encountered, to varying extent, by the resident during training. However, there were no significant differences between the first 15 and following 12 cases, because the supervising urologist coached and directed the resident s movements, and intervened when necessary to help in difficult situations only in the first 15 cases. The attending staff would indicate the correct tissue plane, comment on the depth of incisions, show an alternative movement if there was no progression, and encourage the resident to proceed if he was making the appropriate manoeuvres. The supervisor would take over if the plane of dissection was lost, if there was bleeding hampering vision and if there was difficulty with the initial apical dissection or the final antero-apical incision of mucosal attachments. The morcellation technique was acquired quickly by the resident and the supervisor did not need to interfere at any time during this process. The overall results of this series were comparable with those reported by the supervisor [8]. Gilling et al. [6], in their updated HoLEP series, reported a shorter enucleation time (46.9 min) for a slightly larger mean gland size (75.3 ml), but their results at 1 month were similar to the present, with a reported IPSS of 8.6, and a Q max of 23.4 ml/s [6]. The percentage of tissue retrieved in the present cohort was 42.5% (23.3 g/54.8 ml), compared with 47% (35.5 g/75.3 ml) in the earlier series [6]. One patient developed a urethral stricture; this was reported in 2.3% in another study [9]. One patient had stress urinary incontinence in addition to irritative symptoms, which were present before HoLEP after a previous TURP 9 years earlier; a similar rate of 4.6% (two of 43) with stress urinary incontinence was reported by others

7 LEARNING HoLEP 869 [9]. The most tissue retrieved was 74.4 g from a prostate with a volume on TRUS of 122 g. There were four prostates of > 80 g; the resident did not find these more difficult to enucleate than the other glands, but the operation took longer and good technique became very important. Most of the patients (85%) were discharged catheter-free on the first day after HoLEP and two (7%) required prolonged catheterization. The catheter could have been removed on the same day in many patients, but as all preferred to stay in hospital for the first night, we elected to keep the catheter in until hours the following day. In conclusion, HoLEP can be learnt but requires more training than for TURP. By following a validated technique, under the supervision of an experienced urologist, the learning process is improved and shortened. References 1 Kabalin JN. Holmium:YAG laser prostatectomy canine feasibility study. Lasers Surg Med, 1996; 18: Kabalin JN. Holmium:YAG laser prostatectomy: results of U.S. pilot study. J Endourol 1996; 10: Gilling PJ, Cass CB, Malcolm AR, Fraundorfer MR. Combination holmium and Nd:YAG laser ablation of the prostate: initial clinical experience. J Endourol 1995; 9: 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; 47: Fraundorfer MR, Gilling PJ. Holmium:YAG laser enucleation of the prostate combined with mechanical morcellation: preliminary results. Eur Urol 1998; 33: Gilling PJ, Kennett K, Das AK, Thompson D, Fraundorfer MR. Holmium laser enucleation of the prostate (HoLEP) combined with transurethral tissue morcellation: an update on the early clinical experience. J Endourol 1998; 12: Das A, Kennett KM, Sutton T, Fraundorfer MR, Gilling PJ. Histologic effects of holmium:yag laser resection versus transurethral resection of the prostate. J Endourol 2000; 14: Stephenson AJ, Savard J, Morehouse DD, Taguchi Y, Elhilali MM. Holmium laser enucleation of the prostate with tissue morcellation: a new gold standard for the treatment of benign prostatic hyperplasia?. J Urol 2001; 165 (Suppl.): Gilling PJ, Kennett KM, Fraundorfer MR. Holmium laser enucleation of the prostate for glands larger than 100 g: an endourologic alternative to open prostatectomy. J Endourol 2000; 14: Kabalin JN. Editorial comment. J Endourol 1999; 13: Bukala B, Denstedt JD. Holmium:YAG laser resection of the prostate. J Endourol 1999; 13: Authors A. El-Hakim, MD, FRCS(C), Urology Resident. M.M. Elhilali, MD, PhD, FRCS(C), Chair of Urology. Correspondence: M.M. Elhilali, Royal Victoria Hospital, 687 Pine Avenue West, S6.95 Montreal, Quebec, H3A 1A1, Canada. mostafa.elhilali@muhc.mcgill.ca Abbreviations: HoLEP, holmium laser enucleation of the prostate; QoL, quality-of-life (score); Q max, maximum urinary flow rate; PVR, postvoid residual urine volume.