Symptomatic small non-obstructing lower ureteric calculi: comparison of ureteroscopy and extra corporeal shock wave lithotripsy.MG Andankar, PN Maheshwari, AL Saple, V Mehta, A Varshney, B Bansal
R. G. Stone Urological Research Institute, Mumbai and New Delhi, India., India
OBJECTIVE: To compare the success, efficacy and complications of ureteroscopy (URS) and extra corporeal shock wave lithotripsy (ESWL) for the treatment of symptomatic small non obstructing lower ureteric calculi. SUBJECTS AND METHODS: This prospective non-randomised study was conducted simultaneously at two urological referral centres, included 280 patients with symptomatic small (4-10 mm) lower ureteric calculi (situated below the sacroiliac joint), with good renal function on intravenous urography. Patients were offered both the treatment options. One hundred and sixty patients chose ureteroscopy, whereas 120 patients were treated by ESWL. Standard techniques of ureteroscopy and ESWL were employed. Patients were followed-up to assess the success rates and complications of the two procedures. RESULTS: Ureteroscopy achieved complete stone clearance in one session in 95% of patients. In six patients ureteroscopy had failed initially and was later accomplished in second session improving the success rate to 98.7%. Two patients had a proximal migration of calculus that needed ESWL. Of the 120 patients treated by ESWL, 90% achieved stone free status at three months. Ureteroscopy was needed for twelve patients (10%) where ESWL failed to achieve stone clearance. There were no significant ESWL related complications. ESWL was administered on outpatient basis, while patients needed hospitalisation and anaesthesia for ureteroscopy. CONCLUSION: ESWL can be the primary mode of treatment for symptomatic small non-obstructing lower ureteric calculi as it is minimally invasive and safe. Ureteroscopy can be offered to patients who demand immediate relief or when ESWL fails.
Keywords: Adolescent, Adult, Aged, Comparative Study, Female, Human, Lithotripsy, Male, Middle Age, Prospective Studies, Treatment Outcome, Ureteral Calculi, therapy,Ureteroscopy,
The changes that have taken place in the management of urinary calculus disease within the last decade and a half have been truly remarkable. Whereas, in the past the urologist was faced with only two management options, to operate or not to operate, the numbers of therapeutic choices now have vastly increased. The development of newer endourological instruments meant that calculi could now be managed by lesser invasive means. The ultimate concept of management of stones, ‘non invasion’, has become possible with the increasing use of extra corporeal shock wave lithotripsy (ESWL) worldwide.
Following the report by Perez Castro and Martinez Piniero, transurethral ureteroscopy has rapidly replaced surgery in the treatment of ureteric stone. Since calculi located in the upper ureter lie within the reach of conventional extra corporeal shock wave treatment, ureteroscopy has gained wider acceptance for stones situated distally in the iliac or pelvic ureter. Although very high success rate may be achieved with ureteroscopy, serious complications can be encountered in about 2% of patients.
Over the past few years there have been several studies comparing ureteroscopy and ESWL for the management of lower ureteric calculi. Studies have shown that ESWL has satisfactory results in the management of lower ureteric calculi. Ureteroscopy has an edge in the patients who have large and obstructing calculi with poor renal function. This study was planned in a select group of patients with symptomatic but small and non obstructing lower ureteric calculi.
In this prospective study carried over a period of three years from February 98 to January 01, patients with symptomatic small lower ureteric calculi (4 10 mm), with good renal function on intravenous urography were chosen for treatment. Patients with calculi less than 6 mm. were initially given a trial of conservative treatment. Those patients having persistent pain or not showing movement of the stone on six-week follow up were offered intervention. Only the calculi situated below the sacroiliac joint as seen radiologically were selected in this study. The calculi less than 4 mm or more than 10 mm or those in children and in patients with poor renal status, active urinary tract infection, hydronephrosis and ureteric obstruction were excluded from the study.
After defining the indications of treatment, the patients were made aware of both the modalities of treatment and their probable complications. The pros and cons of ureteroscopy and ESWL were explained. The need for anaesthesia, stent, urethral manipulation, possible complications, need for repeated follow up especially after ESWL, and the cost factor involved, was explained to the patient. The patients were then asked to choose the mode of treatment.
Ureteroscopy was performed with rigid 8 Fr Wolf ureteroscope following dilatation of ureteric orifice. The calculus was fragmented with ballistic energy or holmium laser. Ureteric catheter or a JJ stent was kept in all the patients for 24 hours to 3 weeks. All patients were administered prophylactic antibiotic. ESWL was administered on a ‘Siemens Lithostar’ electromagnetic lithotriptor. Patients who were anxious or could not tolerate the discomfort were given sedatives and analgesics. ESWL was administered in prone position.
Successful treatment was defined as complete stone clearance. After ESWL, complete stone clearance was assessed at three months follow up. The follow up schedule was similar in both the groups of patients. Plain X-rays were obtained 1, 2 and 6 weeks after discharge and thereafter if residual fragments persisted.
One hundred and sixty patients were treated with ureteroscopy (Male/Female = 102/58), while 120 patients were treated by ESWL (Male/Female = 82/38). The patient’s age varied between 18 and 70 years, with maximum number of patients between 21 to 30 years of age.
Ureteroscopy was performed under general or spinal anaesthesia. ESWL did not need anaesthesia, although 24 patients (20%) needed sedation or analgesia for ESWL. After ureteroscopy, ureteric catheter or stent was kept in all patients for 24 hours to 3 weeks. Only four patients required JJ stents in ESWL group. These patients presented with ureteric colic not responding to conservative treatment. Here stents were placed initially for management of colic and the patients later chose ESWL as their treatment option. A total of 120 patients required 224 sessions of lithotripsy with average number of 3500 shock waves at 3.0 kV.
The stone clearance rate was 95% in first session of ureteroscopy. Repeat ureteroscopy was however required in six patients after four weeks. In these patients the initial attempt of ureteroscopy failed due to failure to adequately dilate the ureteric orifice in five and submucosal dissection with false passage in one patient. The proximal migration of calculus occurred in two patients. These patients were treated by ESWL.
ESWL achieved 90% stone free rate at three months. There were no major complications, although two patients developed fever and infection. Seven patients needed analgesics for one day for pain after ESWL. Twelve patients (10%) where ESWL failed were treated by ureteroscopy. The mean hospital stay in ureteroscopy was two days. ESWL was administered on out-patient basis but all patients needed frequent visits for follow-up.
The management of distal ureteric stone continues to invoke controversy. Although the best results emerge from the “marriage of ESWL to ureteroscopy” says Robert Reihle, not all centres can afford this alliance. Nevertheless, the question remains as to what constitutes the current algorithm of management for lower ureteric calculi? Surely, no definite answer exists today.
Ureteroscopy is preferably done under regional or general anaesthesia. General anaesthesia is preferred, as patients perceive pain due to over distension of the pelvi-calyceal system when under spinal or local anesthesia.,
The treatment with ESWL on Siemens Lithostar electromagnetic lithotriptor however, does not require anaesthesia. Patients who are anxious or perceive pain were given intravenous sedation or local anaesthesia in form of lidocaine cream.,
In our study, general or spinal anaesthesia was opted for ureteroscopy in all 160 patients. ESWL did not need anaesthesia, although 24 patients required sedation or analgesics during the procedure.
The stone size in our series ranged from 4 mm to 10 mm, with a majority of patients in 6 to 8 mm group. Patients with stones larger than 10 mm were treated by ureteroscopy and were not included in this study. Success rate for larger stone is definitely better with ureteroscopy, than with shock wave lithotripsy. The number of sessions, radiation exposure, time required for evacuation of fragments, increases in ESWL with increase in size of a calculus.
The routine use of stents after ureteroscopy is somewhat debatable. Weinberg et al recommended keeping a ureteric catheter for 24 to 48 hours after the procedure to prevent colic and to allow minor mucosal perforations to heal. Others have recommended the use of a stent to prevent long term complications and to decrease postoperative morbidity. We have routinely placed stents in all ureteroscopy patients as some ureteric oedema causing upper tract dilatation and dysfunction is expected. Ureteric catheters were placed for 24 to 48 hours in all patients. JJ stents for approximately 3 weeks were kept in patients with impacted calculi, and in patients with prolonged duration of procedure or mucosal injuries.
It has been shown that JJ stents do not necessarily improve the results of ESWL. The insertion of stents not only incurs an additional expense, but also is an invasive procedure associated with complications. We have reserved stents for patients who presented with ureteric colic not responding to conservative treatment.
The success is with regard to the total stone clearance. In our series, ureteroscopy succeeded in the first attempt in 152 (95%). Six patients needed a second session of ureteroscopy improving the success rate to 98.7%. In ESWL, a success rate of 60% was achieved after the first session, which increased to 90% in three sessions.
The reasons for failure in ureteroscopy group were minor ureteric perforation in one, submucosal dissection with false passage in two patients and failure of adequate dilation of ureteric orifice in three patients. Repeat procedure after four weeks succeeded in all these patients. In ESWL group, 12 patients (10%) failed to fragment or evacuate their calculi. The failure in ESWL group was probably related to the stone composition.
Ureteroscopy failed to remove calculus in two patients as the stone migrated up. These were treated with ESWL. Ureteroscopy is an invasive procedure and complications are known in it. Huffman et al described one ureteric reimplantation and eight pyelonephritis and mucosal tears, while Thomas has reported two cases of partial ureteric avulsion and nine mucosal tears in his series. Puppo et al has described a case of ureteric reimplantation for ureteric avulsion that happened in an attempt to overcome a ureteric stenosis.
None of the patients in ESWL group had any major complications although minor complications like pain and fever were observed in nine patients.
In this study, ureteroscopy is found to have marginally higher success rate compared to ESWL. However, ureteroscopy is more invasive. In addition, it has a potential for complications that can be serious. Ureteroscopy needs hospital stay and anaesthesia while ESWL can be done on outpatient basis thereby reducing inconvenience due to hospital admission. We suggest ESWL should be offered as a primary mode of treatment in patients with small and non obstructive lower ureteric calculi, as it is minimally invasive and safe. Ureteroscopy can be offered to patients who demand immediate relief and cannot be kept on follow up of those who fail treatment by ESWL.
[Table - 1], [Table - 2]