Objective To compare the efficacy, safety and durability of transurethral electrovaporiza-tion of the prostate (EVP) and transurethral resection of the prostate (TURP) for benign prostatic hyperplasia (BPH).
Patients and Methods Between September 1999 and January 2002, thirty patients pre-senting to Cairo University Hospital with moderately to severely symptomatic BPH and a prostate weight between 30 and 60 gram were randomized to EVP (16 patients, mean age 62.5 years) or TURP (14 pa-tients, mean age 58 years). Pre and post-operative international prostatic symptom score (IPSS), maximum flow rates (Qmax), postvoid residual urine and complications were recorded in each patient.
Results In the vaporized group, there was a shorter mean catheterization time (EVP 2.1 days vs. TURP 3.4 days) and a shorter

mean hospital stay (EVP 3.2 days vs. TURP 4.9 days). Follow-up data at one year showed a comparable significant improvement in mean IPSS (EVP 4.6 ± 1.2 vs. TURP 4.5 ± 1.3) and Qmax (EVP 17 ml/sec vs. TURP 20 ml/sec) in both groups. In both groups none of the patients demonstrated sphincteric incontinence, but one in each group had a urethral stricture at the bulbomembraneous region requiring visual internal urethrotomy. One patient in each group required operation for residual adenoma.
Conclusion Our results at one year follow-up suggest that EVP is as effective as standard TURP in the management of BPH with a comparable durability.
Key Words benign prostatic hyperplasia, electrovaporization

INTRODUCTION

Benign prostatic hyperplasia (BPH) is one of the most common age-related disorders in men, being present in one out of seven men aged between 40 and 49 years, and in half of the men aged between 60 and 69 years1. Transurethral resection of the prostate (TURP) remains the gold standard treatment for patients with symptomatic BPH with subjective and objective success rates of 85% to 90%2,3. Although success rates are excellent, signi-ficant morbidity is associated with the proce-dure. This includes bleeding, transurethral re-section syndrome, infection, retrograde ejacu-lation, impotence and incontinence3,4. The therapeutic modalities in the management of BPH have changed dramatically over the past 5 years. They include both medical and mini-mally invasive alternative therapies such as microwave thermotherapy, transurethral need-le ablation (TUNA), laser prostatectomy and electrovaporization of the prostate5. All these procedures have evolved in an attempt to
Table 1: Baseline Patient Characteristics

Table 2: Comparison of Operative Time, Mean Catheterization Time and Mean Hospital Stay

research to undergo transurethral electro-vaporization (EVP) or transurethral resection (TURP). Sixteen patients aged between 50 and 70 years (mean age 62.5 years) under-went EVP (Group I), while 14 patients aged between 55 and 70 years (mean age 58 years) underwent (Group II). Preoperatively, all patients were evaluated by history taking, phy-sical examination including digital rectal exa-mination and laboratory evaluation (urine ana-lysis and culture, serum electrolytes, urea, creatinine, blood profile, complete blood pic-ture, blood sugar and assay of PSA level). Voiding symptoms were graded according to the international prostate symptom score (IPSS). The prostate volume was measured by transrectal ultrasonography.

The maximum flow rates (Qmax) were recorded pre and postoperatively (voided volume >150 ml) (Menuet, Dantec, Denmark). The postvoid residual urine volume (PVR) was measured by ultrasonography.

In this study inclusion criteria were an IPSS score >14, a Qmax of < 15 ml/sec and a prostate size ranging from 30 to 60 gram as measured by TRUS (Table 1). Patients with a

Table 3: Changes in IPSS in the TURP and EVP Groups

Table 4: Changes in Qmax (ml/s) in the TURP and EVP Groups

TURP was done with the same principles as described by Nesbit and Mebust2. It is vital that the urologist maintains a three-dimen-sional mental image of the key anatomic land-marks throughout the procedure, the ureteral orifices, the bladder neck, the length and configuration of the prostate (which can be extremely variable in the different patients), the location of the verumontanum, the location of the external urethral sphincter and the relation-ship of these landmarks to the position of the resectoscope and the surgical loop. Resection should be done only when there is orientation of the foregoing and never when the surgeon is uncertain or is lost.

The operation should be undertaken syste-mically, completing resection and haemostasis in one area of the fossa before moving to the next. At the end of the procedure, a 22 Fr. three-way Foley catheter was placed, with con-tinuous saline irrigation. The catheters were removed from all patients when the urine had become clear.

Table 5: Postoperative Complications

The marked increase in Qmax was maintained in both groups but was comparable between the two groups at all assessments. In the EVP group the mean Qmax at 12 months was 17.9 ± 2.8 ml/s compared to the baseline mean of 8.7 ± 2.6 ml/s (102% increase). In the TURP group the mean Qmax at 12 months was 20.5 ± 3.2 ml/s compared to the baseline mean of 9.1 ± 2.8 ml/s (118 % increase) (Table 4).

In both groups, a significant reduction of postvoid residual urine (PVR) compared to the baseline could be noticed at all follow-up assessments and was maintained in both groups, with no significant differences between the groups.

After removal of the urethral catheter, the post-operative irritative symptoms, usually in the form of frequency, were more severe in patients treated with EVP (6 patients) than than in those treated with TURP (4 patients). But in all groups these symptoms lasted for an average of 12 days.

None of the patients demonstrated sphinc-teric incontinence or bladder neck contrac-tures in either group, but one patient in each group had a urethral stricture at the bulbomem-branous region requiring direct visual internal urethrotomy. One patient in each group expe-rienced postoperative obstructive symptoms and required reoperation for residual adenoma.
dies the reported operation time for EVP was in the same range as for TURP13.

In the present study, all patients were de-catheterized when the urine was clear. In the EVP group the mean catheterization time (2-1 days) was significantly shorter than that in the TURP group (3-4 days). Similarly, other in-vestigators reported shorter catheterization times for EVP6,7. Recent studies on TURP reported a mean of 4 days of catheterization in 78% of patients9. The shorter catheterization time in the vaporized group lead to a signify-cantly shorter hospital stay (3-2 days com-pared to 4-9 days for the resected group). Similar results were reported in other TURP and EVP studies2,6,7.

The changes in the haemoglobin (EVP 0.8 gm/ml vs. TURP 1-3 gm/ml) and haemotocrit values (EVP 0.8 ml/dl vs. TURP 1.9 ml/dl) at one day postoperatively were significantly dif-ferent between the two groups. The drop in haemoglobin and haemotocrit in the TURP group was significantly higher than that in the EVP group, which indicates that there was less perioperative bleeding during EVP. The reason for the minimal bleeding in EVP patients is the sufficient contact time between the vaportrode and the underlying prostate tissue which pro-duces a coagulation zone.

A urethral stricture requiring internal ureth-rotomy developed in one patient in each group at the bulbomembraneous region. One patient in each group had postoperative obstructive symptoms and required reoperation for resi-dual adenoma. Kaplan et al.6 reported no reoperation rate after EVP in 114 patients, 79 of them completed one year follow up9,12.

Sphincteric incontinence was not noted in any patient in either group in this study nor in other large EVP studies9. One disadvantage of EVP is the lack of tissue for histological analysis, however, if such tissue is needed, the vaportrode can be exchanged by a routine transurethral resection loop to obtain chips.

In this study, impotence was reported after EVP by 3 of 14 previously potent patients, whereas 2 of 13 TURP potent patients were impotent postoperatively. The difference bet-ween the two groups was not significant. In the UK National Prostatectany Audit’s studies14, the incidence of erectile dysfunction was reported to be 31% while other investigators

7. Temari A, Narayan P. Electrovaporization of the prostate. Br J Urol 1996, 78:667.

8. Gallucci M, Puppo P, Fortunato P, Mauro M, Vincenzoni A, Zaccara A. Transurethral vaporiza-tion of the prostate with the vaportrode VE-B. Eur Urol 1996, 29:450.

9. Wassan JH, Reda DJ, Bruskewitz RC. Complications of transurethral surgery with watch-ful waiting for moderate symptoms of benign prostatic hyperplasia. N Engl J Med 1995, 332:75.

10. Bush IM, Malters E, Bush J. Transurethral vaporization of the prostate. New Horizon Abstract. Soc Min Invas Ther 1993, 2:98.
All correspondence to be sent to:

Ahmed M. Shelbaia, M.D.
Department of Urology
Cairo University Hospital
Cairo
Egypt

decrease the morbidity associated with standard TURP while attempting to mimic its symptomatic results.

Recently, electrovaporization has become popular for the treatment of BPH. The tech-nique of vaporization is not new. It employs an electrode that uses existing electrosurgical generator sources and is capable of producing synchronous vaporization and coagulation of the prostate. Several studies have been performed to assess the efficacy and safety of this procedure in treating bladder outlet ob-struction due to BPH6,7. We conducted this study to compare the efficacy, safety and dura-bility of EVP with conventional TURP in the treatment of men with BPH.

PATIENTS AND METHODS

Between September 1999 and January 2002, 30 patients with moderately to severely symptomatic BPH were included in this

known neurogenic bladder, cancer of the prostate, bladder stones, urethral stricture, or prior history of prostate surgery were excluded from this study. Cases with urine retention were also excluded as the Qmax is a para-meter for postoperative assessment when compared to the preoperative Qmax.

The patients and procedures were evaluat-ed regarding the duration of the operation, postoperative catheterization time and hospital stay, the requirement of blood transfusion and early postoperative complications. Haemo-globin, the haematocrit value and serum sodium were measured one day after the operative procedures and compared with the baseline values. After discharge from the hospital, the follow-up visits were scheduled at 1, 3, 6 and 12 months. The variables evaluated at follow up included IPSS, Qmax, PVR and sexual dysfunction.

Operative technique:

The standard transurethral resection equip-ment was used for both EVP and TURP groups including the Karl Storz 24 Fr. resecto-scope. EVP was performed using the vapor-trode (grooved roller electrode). Electro-vaporization was accomplished at a cutting current with a 25 % to 75 % higher power than standard TURP. The average setting was 250-300 watt for cutting and 60 – 80 watt for coagulation.

Prior to electrovaporization of the prostate, a standard cystourethroscopy was done. The procedure was performed under continuous glycine irrigation. The use of the vaportrode electrode for EVP required no special skills other than those of performing a conventional TURP.

We first vaporized the middle lobe from the area of the bladder neck to the verumontanum. Lateral lobe vaporization was then accomplish-ed in overlapping sweeps from the bladder neck to the level of the verumontanum from the 1 o’clock position to the 5 o’clock position and counter clockwise from the 11 o’clock to the 7 o’clock position until the desired amount of tissue was removed. This was continued until the crossing white fibres of the surgical cap-sule were seen. If tissue was needed, a sampling resection could be performed by just changing to a standard loop electrode during the procedure.

RESULTS

At baseline, the patients in both groups were of comparable age, size of the prostate as measured by TRUS, symptom score, Qmax and PVR. The duration of follow up was also comparable in both groups (Table 1).

The mean operative time in Group I was 54.5 minutes (range 35-70 minutes), while it was 49.5 minutes (range 45-70 minutes) in Group II with no statistically significant differ-ence (P>0.05). None of the patients in either group experienced TUR syndrome or signi-ficant bleeding requiring blood transfusion.

Transient haematuria was noted in three patients after TURP and in two after EVP, all resolving within two weeks of the procedure. The mean catheterization time was significant-ly longer after TURP than after EVP (EVP 2.1 days vs. TURP 3.4 days). The mean hospital stay was also significantly longer after TURP than after EVP (EVP 3.2 days vs. TURP 4.9 days) (Table 2).

The difference between baseline and post- operative haematocrit (mean change in EVP 0.8 ml/dl and in TURP 1.9 ml/dL, P< 0.001) and haemoglobin (mean change in EVP 0.8 gm/ml and in TURP 1.3 gm/ml) was significant in both groups.

There was no significant change between baseline and mean postoperative serum so-dium in either group (EVP 1.3 mEq / l and TURP 1.6 mEq / l).

Compared with the baseline values, the postoperative symptom scores (IPSS) improv-ed significantly in both groups at all follow-up assessments, and the significant improvement was maintained in both groups during the entire follow-up period. There was no signi-ficant difference in symptom scores between the two groups at any of the follow-up assess-ments. In the TURP group the mean IPSS at 12 months was 4.5 ± 1.3 compared to the baseline mean of 19.4 ± 1.2 representing a mean difference of 14.5 (75.2 % reduction, P < 0.001 ). In the EVP group the mean IPSS at 12 months was 4.6 ± 1.2 representing a mean difference of 13.4 (71.1 % reduction P < 0.001) (Table 3).

The difference in Qmax in both groups was significant at all follow-up assessments when compared with the baseline values (P < 0.001).

Before treatment, 13 TURP patients and 14 EVP patients had reported an erectile function sufficient to achieve penetration during inter-course. Of those, two patients of the TURP group and three of the EVP group complained of impotence after treatment. Ten potent patients of the TURP group complained of re-trograde ejaculation and 9 potent patients of the EVP group complained of retrograde eja-culation (Table 5).

DISCUSSION

Transurethral resection of the prostate (TURP) is still the gold standard treatment for patients with bladder outlet obstruction due to BPH, with subjective and objective success rates of 85-90%3. However, large studies on TURP have reported significant morbidity rates as high as 18% including bleeding, TUR syn-drome, urethral stricture, bladder neck ste-nosis, incontinence and impotence8,9. In 1993, Bush et al.10, described transurethral electro-vaporization of the prostate using the grooved ball electrode. We conducted a randomized trial to compare the efficacy, safety and dura-bility of EVP with standard TURP in patients with moderate to severe symptomatic BPH.

In this study the patients of both groups showed a comparable significant improvement which was maintained at one year follow-up. This parallels and complements the findings reported by other investigators6,7,11 and indi-cates that EVP is as effective as TURP in the treatment of symptomatic BPH with a similar durability. There was a statistically significant decrease in mean IPSS in both groups.

At one year follow up, there was no signi-ficant difference in symptom scores between the two groups (EVP 4.6 ± 1.2 vs. TURP 4.5 ± 1.3)9. Smilar results were noted in other studies comparing TURP and EVP6,7,12. In this study, a statistically significant improvement was also obtained in mean Qmax in both groups. The improvement of the mean Qmax in EVP patients reported in the literature was 110-140%5,11 compared to 102% in this study. In the TURP group this value was reported to be 125% in the literature5. We found it to be
118 % in our TURP group.

The mean operative time for the TURP group was 54.5 minutes while it was 49.5 minutes for the EVP group with no statistically significant difference. However, in other stu-

did not report any erectile dysfunction after EVP6,7,11.

Based on our preliminary findings, a low intraoperative and perioperative morbidity, a rapid convalescence time and short hospital stay and the simplicity of the procedure make EVP a potentially useful, safe and versatile tool in the therapeutic armamentarium of BPH. Because of its unique electrosurgical pro-perties, higher risk patients, especially those on anticoagulation therapy can be treated suc-cessfully by this technique.

It should be emphasized that electrovapo-rization should be viewed as an alternative me-thod to be used beside the gold standard transurethral resection of the prostate. The prostate size in our two groups was <60 gm, and both EVP and TURP were found comparable for prostates < 60 gm. TURP may, however, be advantageous in large prostates.

Our early experience leaves us cautiously optimistic, however, a longer follow up with a larger number of patients will be essential to determine the durability of EVP as a treatment for symptomatic BPH.

REFERENCES

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2. Mebust WK, Holtgrewe HL, Cockett AT, Peters PC. Transurethral prostatectomy. Immediate and postoperative complications. A co-operative study of 13 participating institutions evaluating 3885 patients. J Urol 1989, 141:243.

3. Holtgrewe HL, Mebust WK, Dowd HB, Cockett AT, Peters PC, Proctor C. Transurethral prostatectomy procedure. Aspects of dominant operation in American Urology. J Urol 1989, 141:228.

4. Ross NP, Mennberg JE, Maleka DJ et al. Mortality and reoperation after open and transurethral resection of the prostate for BPH. N Engl Med J 1989, 320:1120.

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6. Kaplan S, Santorosa P, Te AE. Transurethral electrovaporization of the prostate. One year experience. Urology 1996, 48:876.

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12. Narayan P, Temari A, Grazotto M. Transurethral electrovaporization of prostate. Physical principles, results and complications. Urology 1996, 47:505.

13. Kaplan SA. Transurethral electrovaporization of the prostate. A novel method for treating men with benign prostatic hyperplasia. Urology 1995, 45:566.

14. Neal DE. National Prostatectomy Audit. Br J Urol 1997, 79:69.