Clinical Experience with the Swiss Lithoclast Master in Treatment of Bladder Calculi

Abstract

Background and Purpose:

Bladder calculi account for 5% of urinary tract calculi in the Western world, and many different treatment modalities have been presented throughout the decades. We report our clinical experience using the Swiss LithoClast® Master (SLM).

Materials and Methods:

The SLM is a rigid, hand-held endourologic probe including a pneumatic lithotriptor and an ultrasonic lithotriptor. Attached to the ultrasonic modality is a suction system. The two lithotriptor modalities are controlled by a footswitch and can be activated separately or simultaneously. The SLM is used via a rigid endoscope. Indications for treatment were medical complaints such as hematuria, lower urinary tract symptoms, pain, recurrent urinary tract infections, recurrent bursts of balloon in indwelling catheters, and difficulties performing clean intermittent self-catheterization.

Results:

From August 1, 2009, to August 1, 2011, 27 patients were treated for bladder calculi (24 men). Five had a neurogenic voiding dysfunction, 3 had prostate cancer, and 19 had benign prostatic enlargement or detrusor muscle insufficiency. Median age was 74 years (range 45–86 years). Stone clearance was obtained in 26 (96%) patients. Stone burden was one or multiple bladder calculi. Median stone size of the largest stone in each patient was 20 (5–40) mm. Under the same anesthesia, two patients underwent a transurethral resection of the prostate because of a very large prostate. Median lithotripsy time was 60 (range 20–144) minutes. All patients were discharged within 24 hours.

Conclusion:

The method described is a safe and quick method for endoscopic lithotripsy of bladder calculi rendering the patients stone free in the vast majority of cases. The procedure can be performed as day-case surgery.

Introduction

The formation of bladder calculi has been known since the earliest of times. The oldest reported bladder stone is estimated to be more than 7000 years old¹ and was found in the pelvis of a skeleton of a predynastic Egyptian boy. Also, the management of stones has been known in very early times, performed by Hindu surgeons and by the Egyptians.

Today, bladder stones account for approximately 5% of all urinary tract calculi in the Western world. They are known to be caused by infection, bladder outlet obstruction (BOO), neurogenic voiding dysfunction, foreign bodies, and bladder-augmentation surgery using the ileum or colon.² In third-world countries, bladder calculi are still seen to be caused by nutritional deficiencies, especially in children.

Many different treatment modalities have been used in the past, originating with open surgery and progressing further to percutaneous vesicolithotomy and then urethroscopic manipulation and extraction. Noninvasive extracorporeal shockwave lithotripsy (SWL) is also a treatment modality for bladder calculi in selected patient groups. The disadvantage of noninvasive stone fragmentation is the potential risk of not clearing the stone material, especially in patients with incomplete bladder emptying.

During the past 10 to 15 years, endourologic techniques have improved significantly. Some of the current modalities for cystoscopic lithotripsy include mechanical, ultrasonic, electrohydraulic, and laser lithotripsy, as well as the relatively new ballistic Swiss LithoClast® system (EMS).³ This system has been further developed into the Swiss LithoClast Master (SLM) (Fig. 1), which consists of three modalities: A pneumatic device, an ultrasound device, and a suction device, all incorporated in one handpiece.

FIG. 1.

The Swiss LithoClast® Master.

The pneumatic, the ultrasound lithotripsy, and the suction unit are controlled by a single unit hooked up to the hospital power supply, the air pressure system, and a vacuum pump. It is controlled by a foot switch with two pedals either activating the pneumatic part (right pedal) or the ultrasound and the suction part together (left pedal). By activating the two pedals simultaneously, both the pneumatic and ultrasound modality including suction are activated.

The pneumatic part can be activated at a low frequency, gently fragmenting large hard stones into smaller pieces that then can be removed easily at the same time. This enhances the surgical comfort in avoiding numerous movements.

In this study, we present our experience with the SLM in a consecutive series of patients treated for bladder calculi. To the best of our knowledge, this is the first study in the English literature on pneumatic lithotripsy of bladder calculi using only the SLM.

Patients and Methods

At Aarhus University Hospital in Denmark, endoscopic management of bladder stones from August 1, 2009, to August 1, 2011 was evaluated retrospectively. Inclusion criteria were bladder stones >1.5 cm or multiple calculi treated only with the SLM. Twenty-seven consecutive patients were included in this study: 24 men and 3 women. Indications for treatment were based on a variety of medical complaints including gross hematuria (12), recurrent urinary tract infections (5), lower urinary tract symptoms (LUTS) (2), pain (2), recurrent burst of the balloon in suprapubic and indwelling catheters (4), difficulties performing clean intermittent self-catheterization (1), stone found by coincidence because of control program for sigmoid cancer (1). Several patients had more than one of the above-mentioned symptoms. In sum, 16 patients had LUTS at inclusion.

Five of the 27 patients had a neurogenic voiding dysfunction (1 with multiple sclerosis, 2 tetraplegic, 1 paraplegic, and 1 with Parkinsonism). The median age was 74 years (range 45–86 years).

All calculi were diagnosed or verified by cystoscopy. Patients with hematuria also underwent a CT scan that further confirmed the presence of bladder calculi, and the exact size of the largest stone was measured. Stone measurement for patients not undergoing a CT scan was made by the surgeon performing the cystoscopy and bladder stone removal. All procedures were performed by two experienced endourologists.

Urine culture was performed for all patients preoperatively, and infections were treated with appropriate antibiotics. Prophylactic antibiotics were administered during the procedure in all cases (gentamicin 240 mg and ampicillin 3 g).

The procedure was performed under general anesthesia with the patient in the lithotomy position. Initially, cystoscopy was performed to confirm the number and size of stones and also to assess any pathology of the bladder.

In the female patients, a minipercutaneous scope (2F) was used. Because of the length of the male urethra, a longer scope was used in the male patients (a 26F rigid nephroscope [Storz]). Through this, the SLM was introduced. A 2-mm LithoClast probe was used, transmitting compressed-air driving ballistic energy to the calculus at a frequency of 12 cycles per second. The ultrasound device/suction device was used simultaneously and sometimes separately. All smaller fragments were removed by use of the suction device or by bladder irrigation (Ellik evacuator). Larger fragments were extracted from the bladder using a nitinol tipless stone extractor (Perc NCircle® (Cook Medical)). Stone analysis was not performed.

Results

Patient characteristics and operative results are shown in Table 1.

Table 1.

Patient Data and Operative Results

Patient (sex/age)	Stone etiology	No. and size of largest stone (cm)	OR time (min)	Complications and stone clearance	Hospital stay (days)
M (46)	NGB	2 (3.0)	90	None/Yes	0
M (75)	BPE	Multiple (0.5)	20	None/Yes	0
F (70)	NGB	1 (>1.5)	115	None/Yes	1
M (71)	BPE	1 (2.5)	40	None/Yes	1
M (69)	BPE	2 (2.2)	44	None/Yes	0
M (79)	BPE	4 (1.5)	75	None/Yes	0
M (57)	BPE	1 (3.0)	60	None/Yes	0
M (84)	PCA	Multiple (small)	38	None/Yes	0
M (60)	NGB	5 (small)	20	None/Yes	0
F (45)	NGB	Multiple (2.0)	35	Yes/Yes	1
M (83)	PCA	1 (>1.5)	47	None/Yes	1
M (75)	BPE	1 (2.0)	27	None/Yes	0
M (79)	BPE	2 (2.0)	132	Yes/Yes	1
M (48)	NGB	Multiple (2.0)	35	None/Yes	0
M (69)	BPE	2 (2.0)	22	None/Yes	0
M (81)	BPE	1 (2.0)	35	None/Yes	1
M (67)	BPE	12 (2.0)	105	None/Yes	0
M (79)	BPE	2 (4.0)	140	None/Yes	0
M (82)	CUR	4 (1.5)	54	None/Yes	1
M (70)	BPE	4 (2.0)	65	None/Yes	1
M (64)	BPE	3 (2.0)	92	None/Yes	0
M (76)	PCA	6 (2.0)	95	None/Yes	1
M (75)	BPH	40 (2.0)	87	None/Yes	1
F (48)	CUR	1 (2.5)	70	None/Yes	0
M (86)	BPE	15 (2.0)	70	None/Yes	0
M (74)	BPH	4 (1.7)	25	None/Yes	1
M (77)	BPE	1 (3.0)	144	None/Yes	0

OR=operating room; NGB=neurogenic bladder; BPE=benign prostate enlargement; PCA=prostate cancer with bladder outlet obstruction; CUR=chronic urinary retention; BPH=benign prostatic hyperplasia.

Twenty-seven procedures were performed with a median operative time of 60 minutes (range 20–144 min). Eight patients had only one stone, five patients had two stones, five patients had three to four stones, and nine patients had >4 stones. The largest stone size was a median of 2.0 cm (range 0.5–4.0 cm).

All patients except one obtained bladder stone clearance after one procedure (26/27=96%). Two patients underwent transurethral resection of the prostate (TURP) during the same anesthesia because of a very large prostate.

The only intraoperative complication was because of a fragment stuck in the tip of the nephroscope in the navicular fossa. The stone was removed after making an incision of the external orifice to extract the stone. This prolonged the operative time and caused minor bleeding from the urethral incision. Two minor fragments were left in the bladder, and a second procedure was planned. The patient was given an indwelling catheter to be removed after 10 days.

One patient also having a ureteral stone had a Double-J-stent placed. She was admitted to the hospital 2 days later with urosepsis and was treated with relevant antibiotics. No other intraoperative or postoperative complications were reported.

Sixteen patients were discharged from hospital the same day, and 11 patients were discharged the day after. Overall, the majority of patients were discharged within 24 hours of the procedure, including the three patients who had TURP or a meatotomy performed.

Patients with LUTS were followed up 1 to 2 months postoperatively including evaluation of flow and postvoid residual urine (PVR) volume and also, in relevant cases, booked for a urodynamic evaluation. The majority of patients with LUTS before bladder stone removal had no symptoms after the procedure and wished no further follow-up (11 patients). Four patients had a further follow-up at 6 months (two patients for whom an alpha-blocker was prescribed and the two patients having TURP performed at the same time as bladder stone removal). All were without further LUTS, and the follow-up was ended. One patient was designated to have TURP performed at a later session.

Three patients with prostate cancer continued their outpatient control and treatment regime. Patients with a neurogenic voiding dysfunction (5) or chronic urinary retention (2) continued their catheterization regime. Two patients died because of other illnesses before further follow-up, including the patient for whom a meatotomy was performed.

Discussion

For many years, the gold standard in treating patients with bladder stones was open surgery. The often significant postoperative convalescence associated with this procedure, however, has led to the development of less invasive options and endoscopic devices for transurethral fragmentation and extraction: Mechanical, laser lithotripsy, ultrasound, electrohydraulic, and SWL. The Swiss LithoClast was developed in the early 1990s as a new ballistic lithotripsy device and supplemented the above-mentioned well documented methods of lithotripsy.³

Over time, these different treatment modalities have been evaluated and compared in terms of therapeutic efficacy and adverse effects, and each holds its advantages and limitations.

Mechanical crushing lithotriptors (eg, the Mauermeyer) are able to fragment stones effectively but have limitations in the treatment of large and hard stones. Furthermore, this technique includes heavy and large instruments, the need for a greater degree of skill, and the visual field is limited. The risk of injuries to the urethra, bladder perforation, and significant postoperative hematuria are also major drawbacks.^4,5

Laser lithotripsy is widely used and frequently described in the literature.^3,5,6 Results regarding stone clearance are good.^2,6 Possible drawbacks are the risk of bladder perforation and limitations in fragmenting very hard stones.^3,7

Ultrasonic lithotriptors are largely untraumatic, but the procedure can be time consuming, and hard stones may be resistant to fragmentation. Electrohydraulic lithotripsy represents the earliest form of nonmechanical lithotripsy (late 1950s). It has a very high fragmentation rate but can cause extensive tissue injury, including bladder perforation. In addition, electrode-tip breakage has been reported.^3,4

SWL has been reported to be successful in the management of most upper urinary tract calculi, but in the management of bladder calculi, it is recommended to use endourologic treatment modalities because of the risk of injury to the gonads and the prostate.² In addition, the efficacy is influenced by calculus size, and the passage of fragments may be troublesome.

The number of viable treatment modalities reflects that effective treatment of large and hard calculi in the bladder constitute a major problem. This can, to some extent, be resolved by using the SLM. The LithoClast has been reported to be the most effective endoscopic lithotriptor judged by stone fragmentation,^8,9 and its clinical effectiveness in fragmenting stones of various compositions throughout the urinary tract either transurethrally^{3,5,6,8

–17} or percutaneously^{14,18

–25} has been well documented. It has been shown to be a fast and effective method and has proven to be safe and cause very little tissue damage demonstrated both macroscopically and microscopically in pig models.^7,26

The LithoClast has been further developed to consist of three modalities: An ultrasonic device, a pneumatic device, and a suction device all incorporated in one handpiece–the SLM. The combination of the LithoClast and ultrasound counteracts the weaknesses of each method used individually and, also, the two combined with a suction device makes it highly effective. The suction device facilitates contact with the stone and enables removal of small stone fragments.

Not many have reported on the newly improved version, except Haupt and associates⁸ in 2001, who used a previous version of the SLM. In their study, they managed to demonstrate handling of renal calculi. They did not show the benefits of the SLM on bladder calculi. In our study, we have demonstrated the benefit of using the SLM on bladder stones.

In our series of 27 consecutive patients, the median operative time of 60 minutes is quite acceptable, bearing in mind that some of the patients had a rather large stone burden. Patients with a stone burden up to three stones or less had a median operative time of 60 minutes, whereas patients with more than three calculi had a median operative time of 75 minutes. All 27 patients had successful stone disintegration, and after only one procedure, 26 patients were stone free. No major complications occurred during the procedure or postoperatively, but longer follow-up is needed on a larger scale to ascertain the true urethral stricture rate potentially caused by the relatively large nephroscope used in male patients.

The majority of patients (16) were discharged on the day of the operation and the remaining the day after. All patients were discharged within 24 hours. This makes it possible to treat this patient type on an outpatient basis in a day surgery unit, and this has just recently been launched at our institution. Cost reduction is a major concern at any health care unit and makes this option attractive.

Many studies on management of bladder stones discuss possible advantages of performing a TURP at the same time. Patients in the present study were not sampled on the basis of having LUTS, and therefore our results cannot answer this question. The patients with recurrent urinary tract infections, LUTS, and complications from an indwelling catheter as a cause of bladder stone formation, however, could have an underlying nonneurogenic obstructive voiding dysfunction.

We did, however, in our consecutive series not routinely perform TURP during the same anesthesia, even though one could suspect infravesical obstruction caused by benign prostatic enlargement or prostate cancer. In two patients, we chose to perform TURP in the same session because of a very large prostate. The reason we chose this approach is based on the conviction that patient complication rates^{13,16,20,27,28} are increased if the two procedures are performed simultaneously, and the hospital stay and thereby the overall costs are increased.

Furthermore, recent studies have questioned the traditional teaching^29,30 that bladder lithiasis constitutes an absolute indication for prostate surgery based on the assumption that there is a strong association between BOO and bladder lithiasis. Millan-Rodriguez and colleagues³⁰ in 2004 published a study based on the urodynamic findings before and after noninvasive management of bladder calculi and demonstrated that only 50% of patients who presented with bladder calculi had urodynamic evidence of BOO. Furthermore, the urodynamic findings consistently persisted after achieving stone clearance, so they were not influenced by the presence of bladder calculi.

In 2002, O'Connor and coworkers²⁸ presented a retrospective study of 23 men with bladder calculi secondary to benign prostatic hyperplasioa (BPH). All patients were treated with transurethral stone removal. Subsequently, they were medically treated for BPH (alpha-blocker and 5-alpha reductase inhibitor) and had a 30-month follow-up. Of the entire group of 23 patients, a 48.6% reduction in the International Prostate Symptom score was observed and a 49% decrease in the postvoid residual (PVR) urine volume. Only a total of 14 complications were reported. These occurred within the same patient group involving only five patients. The vast majority of these patients were successfully treated with a combination of stone removal and medical treatment.

In addition, the American Urological Association guidelines do not consider bladder stones as a complication of BPH because the vast majority of patients with high PVR do not form bladder calculi.³⁰ This is also the case in the European Association of Urology 2009 guidelines for transurethral resection of the prostate.³¹

TURP in combination with intracorporeal lithotripsy is still somewhat controversial, because some studies have shown no significant postoperative morbidity or increased complication rate when patients are treated for bladder calculi in combination with TURP.^5,14 At present, it is our conviction that using the SLM in a single procedure without performing TURP may be the best and safest procedure. This allows the patient to be discharged stone free within 24 hours and subsequently perform a follow-up on an outpatient basis for diagnosing possible causes of LUTS.

Conclusion

The SLM is a modern, safe, fast, and cost-effective treatment for patients with bladder calculi. Further advantages include its simplicity, reliability, and ease of use for the physician and nursing personnel.¹⁰

Disclosure Statement

No competing financial interests exist.

Footnotes

Abbreviations Used

References

Riches

. The history of lithotomy and lithotrity. Arnott Demonstration delivered at the Royal College of Surgeons of England on January 24, 1967; 185–199. Available at http://pubmedcentralcanada.ca/pmcc/articles/PMC2312308/pdf/annrcse00257-0003.pdf. Accessed on February 26, 2013 .

Papatsoris

, Varkarakis

, Dellis

, Deliveliotis

. Bladder lithiasis: From open surgery to lithotripsy. Urol Res, 2006; 34:163–167.

Zheng

, Denstedt

. Intracorporeal lithotripsy: Update on technology. Urol Clin North Am, 2000; 27:301–313.

Razvi

, Song

, Denstedt

. Management of vesical calculi: Comparison of lithotripsy devices. J Endourol, 1996; 10:559–563.

Sinik

, Isen

, Biri

, et al. Combination of pneumatic lithotripsy and transurethral prostatectomy in bladder stones with benign prostatic hyperplasia. J Endourol, 1998; 12:381–384.

Kara

, Resorlu

, Cicekbilek

, Unsal

. Transurethral cystolithotripsy with holmium laser under local anaesthesia in selected patients. Urology, 2009; 74:1000–1003.

Piergiovanni

, Janssen

, Cochand-Priolett

, et al. Ureteral and bladder lesions after ESWL, with Swiss Lithoclast, electrohydralic shocks, laser Holmium-YAG and Ultrasound: An experimental study. J Endourol, 1993; 7:R10.

Haupt

, Sabrodina

, Orlovski

, et al. Endoscopic lithotripsy with a new device combining ultrasound and lithoclast. J Endourol, 2001; 15:9:929–935.

Hofbauer

, Hobarth

, Marberger

. Lithoclast: New and inexpensive mode of intracorporeal lithotripsy. J Endourol, 1992; 6:429–432.

10.

Denstedt

, Eberwin

, Singh

. The Swiss Lithoclast: A new device for intracorporeal lithotripsy. J Urol, 1992; 148:1088–1090.

11.

Wadhwa

, Hemal

, Sharma

. Intracorporeal lithotripsy with the Swiss Lithoclast. Br J Urol, 1994; 74:699–702.

12.

Terai

, Takeuchi

, Terachi

, et al. Intracorporeal lithotripsy with the Swiss Lithoclast. Int J Urol, 1996; 3:184–186.

13.

Chtourou

, Ben Younes

, Binous

, et al. Combination of ballistic lithotripsy and transurethral prostatectomy in bladder stones with benign prostatic hyperplasia: Report of 120 cases. J Endourol, 2001; 15:851–853.

14.

Tugcu

, Polat

, Ozbay

, et al. Percutaneus versus transurethral cystolithotripsy. J Endourol, 2009; 23:237–241.

15.

Schock

, Barsky

, Pietras

. Urolithiasis update: Clinical experience with the Swiss LithoClast. J Am Oseopath Assoc, 2001; 101:437–440.

16.

Asci

, Aybek

, Sarikaya

, et al. The management of vesical calculi with combined optical mechanical cystolithotripsy and transurethral prostatectomy: Is it safe and effective?. BJU Int, 1999; 84:32–36.

17.

Shah

, Hegde

, Shah

, et al. Simultaneous transurethral cystolithotripsy with holmium laser enucleation of the prostate: A prospective feasibility study and review of literature. BJU Int, 2006; 99:595–600.

18.

Zhu

, Xi

, Wang

, et al. Percutaneous nephrolithotomy for proximal ureteral calculi with severe hydronephrosis: Assessment of different lithotriptors. J Endourol, 2010; 24:201–205.

19.

Franzoni

, Decter

. Percutaneous vesicolithotomy: An alternative to open bladder surgery in patients with an impassable or surgically ablated urethra. J Urol, 1999; 162:777–778.

20.

Richter

, Ringel

, Sluzker

. Combined cystolithotomy and transurethral resection of prostate: Best management of infravesical obstruction and massive or multiple bladder stones. Urology, 2002; 59:688–691.

21.

Aron

, Goel

, Gautam

, et al. Percutaneous versus transurethral cystolithotripsy and TURP for large prostates and large vesical calculi: Refinement of technique and updated data. Int Urol Nephrol, 2007; 39:173–177.

22.

Wollin

, Singal

, Whelan

, et al. Percutaneous suprapubic cystolithotripsy for treatment of large bladder calculi. J Endourol, 1999; 13:739–744.

23.

Sofer

, Kaver

, Greenstein

, et al. Refinements in treatment of large bladder calculi: Simultaneous percutaneous suprapubic and transurethral cystolithotripsy. Urology, 2004; 64:651–654.

24.

Kamat

. Transurethral resection of prostate and suprapubic ballistic vesicolithotrity for benign prostatic hyperplasia with vesical calculi. J Endourol, 2003; 17:505–509.

25.

Rai

, Patrulu

, Rai

, et al. Lithoclast Master in intracorporeal lithotripsy during percutaneous nephrolithotomy: Our experience. MJAFI, 2008; 64:232–233.

26.

Denstedt

, Razvi

, Rowe

, et al. Investigation of the tissue effects of a new device for intracorporeal lithotripsy—the Swiss Lithoclast. J Urol, 1995; 153:535–537.

27.

Nseyo

, Rivard

, Garlick

, Bennett

. Management of bladder stones: Should transurethral prostatic resection be performed in combination with cystolitholapaxy?. Urology, 1987; 29:265–267.

28.

O'Connor

, Laven

, Bales

, Gerber

. Nonsurgival management of benign prostatic hyperplasia in men with bladder calculi. Urology, 2002; 60:288–291.

29.

Millán-Rodríguez

, Izqueirdo-Latorre

, Montlleo-Gonzales

, et al. Treatment of bladder stones without associated prostate surgery: Results of a prospective study. Urology, 2005; 66:505–509.

30.

Millán-Rodríguez

, Errando-Smet

, Rousaud-Barón

, et al. Urodynamic findings before and after noninvasive management of bladder calculi. BJU Int, 2004; 93:1267–1270.

31.

Marszalek

, Ponholzer

, Ousman

, et al. Transurethral resection of the prostate. Eur Urol Suppl, 2009; 8:504–512.