Efficacy of Pneumatic Lithoclast in the Management of Urolithiasis in Upper, Middle and Lower Ureter

Litrature review reveals prevalence of urinary stones for ages as proved by different archeological studies. Renal and blaader stones were also discovered in Egypsian Mummies. Urolithiasis was associated with worst morbidity and mortality, although Egypsians were expert in conservative treatment but did not have enough expertise to take out urinary calculi [1,2]. Stone disease is on rise worldwide primarily as a result of increase in prosperity and changing dietary habits in almost all social groups of the world. Afro-Asian belt includes the United Arab Emirates, Sudan, Indonesia, Philippine, Saudi Arabia, Islamic Republic of Iran, Egypt, India, Myanmar, Thailand and Pakistan. The reported incidence of stone disease in these regions has been found to be 4-20% for all age groups [3,4,5]. In Pakistan prevalence of kidney stones is 16% as quoted by Rizvi et al. Incidence (100,000) as extrapolated by operating room statistics varies in different geographical locations. It varies from 0.2-9.4 in the North, 10.5 in North Sindh, 200 in South Sindh and 11.1 to 28 in Balochistan [6] Pathophysiology of stone formation is an inter-play between promoters and inhibitors of crystallization, along with urine PH and urine flow rate.


Introduction
Litrature review reveals prevalence of urinary stones for ages as proved by different archeological studies. Renal and blaader stones were also discovered in Egypsian Mummies. Urolithiasis was associated with worst morbidity and mortality, although Egypsians were expert in conservative treatment but did not have enough expertise to take out urinary calculi [1,2]. Stone disease is on rise worldwide primarily as a result of increase in prosperity and changing dietary habits in almost all social groups of the world. Afro-Asian belt includes the United Arab Emirates, Sudan, Indonesia, Philippine, Saudi Arabia, Islamic Republic of Iran, Egypt, India, Myanmar, Thailand and Pakistan. The reported incidence of stone disease in these regions has been found to be 4-20% for all age groups [3,4,5]. In Pakistan prevalence of kidney stones is 16% as quoted by Rizvi et al. Incidence (100,000) as extrapolated by operating room statistics varies in different geographical locations. It varies from 0. 2-9.4 in the North, 10.5 in North Sindh, 200 in South Sindh and 11.1 to 28 in Balochistan [6] Pathophysiology of stone formation is an inter-play between promoters and inhibitors of crystallization, along with urine PH and urine flow rate. stone symptoms mimick lower urinary tract infection symtoms, pain may radiates to tip of penis in male, other symptoms may be hematurea or infection related manifestations, in certain percentage stones are picked as incidental finding. Decision to treat kidney/ ureteric stone depends upon stone composition, size location and expertise of the surgeon. Not only various surgical techniques have evolved over the years but various lithotriptic techniques are in use for decades which includes shock wave lithotripsy, laser lithotripsy, and electro hydraulic and pneumatic lithotripsy. These techniques may be used through intra corporeal or extracorporeal method [9,10]. Comparing these methods in terms of safety, efficacy and cost effectiveness Pneumatic lithotripsy has been found to be most suitable choice.
Objective: To determine the efficacy and safety of pneumatic Lithoclast in the management of ureteric calculi in upper, middle and lower part of the Ureter.

Patients and Methods
This was comparative interventional longitudinal study, conducted at Department of Urology, Mayo Hospital Lahore over a period of 02 years from Jan 2015 till Jan 2017. 140 patients with ureteric calculi were taken on the basis of 95% confidence level, 10% prevalence of urolithiasis and 5% margin of error. Inclusion criteria were ureteric calculi, diagnosed on the basis of pain, lower urinary tract symptoms and symptoms suggestive of obstructive uropathy. Diagnosis was confirmed by X-ray KUB (kidney Ureter bladder), intra venous Urography and ultrasonography. Patints having age <12 years, Skeleton deformity, non functioning kidneys, patients with ureteric pathology and ureteroscopic failure were excluded from the study. Out of total 156 patients 16 were excluded and 140 were finally enrolled. These 140 patients were divided into 3 groups depending on the location of ureteric stone. Group included patients with stone in upper Ureter, while Group B and C in middle and lower third of Ureter.
Selected patints underwent ureteroscopic Pneumatic lithotripsy under spinal or general anesthesia with the help of Wolf 8.5 for rigid Ureteroscopic and Wolf 2mm pneumatic Lithoclast probe. At the end 4 frureteric stent was placed for 24 hours. Post operatively pain was managed with pain killers, Stone clearance was assessed by KUB on next day, cases where stone clearance was not complete, was assessed again at 6 weeks. Retained fragments at 6 weeks were labeled as failure of procedure and other modalities were used for fragments removal. Complications like fever, hematurea and stone migration was noted. Data was analyzed through SPSS 22.0. All qualitative data was presented as frequency and percentages and quantitative variable as mean + SD .ANOVA was applied for quantitative and Chi-square for qualitative variable. A p-value of <0.05 was taken as significant. Mean age of 140 patients was 37.27 + 9.95 years, minimum and maximum age of patients was 18 and 55 respectively. Overall gender distribution shows that there was female preponderance, 65 were males and 75 were female patients. 60 patients were assigned to group A, 37 to group B and 43 to group C (Table 1)

Discussion
Urologic management has changed considerably over last 20 years. Various techniques of ureteroscopic and lithotripsy have been used Pneumatic lithotripsy has been most widely used method of stone disintegration [11]. Whatever the mode of lithotripsy used for ureteric stones, there is always a risk of stone migration upward. Pneumatic lithotripsy is more popular amongst urologist because of its low cost, high success rate, low complication rates and well established efficacy for different types of stones including calcium, oxalate monohydrate and cystine stones [12]. Overall success rate quoted for Pneumatic lithotripsy ranges from 70.7-96.8% [13]. In this study overall success rate was 88.57%, success rate for upper ureteric stones was 77.33%, while it was 100% for middle and lower Ureter. Murtadhsa in his study reported success rate of 71.66%, age range in his study was 17-52 years with male predominance (M: F ratio 1.4:1) [14].
Comparing success rates with other local studies reveal success rate of 92% by Shahid et al which is higher than our study and 87.9% by Hussain et al from Ziaudin hospital Karachi [15]. Study by Mareno et al reported overall success rate of stone clearance by 90%, location wise it was 91.3% for upper Ureter and 88.9% for middle and lower Ureter [16]. Another local study by Akhtar et al reported complete fragmentation of 71.1% for upper ureteric stone, 97% for middle and 99.1% for lower ureteric stones [17]. Success rate for upper ureteric stone in our study is lower than study by Mareno et al but higher than study by Akhtar et al, while clearance of middle and lower ureteric stone in our study is higher than other studies. Complication rate in our study was 28.57% comparable to other studies. For upper ureteric stones complication rate was 18.33% while for middle and lower ureteric stone it was 35.13% and 37.20% respectively. Most studies published between 1996 and 2003 narrate an overall ureteroscopic complication as low as 7%. Incidence of minor complication in our study was 4.5% as compared to 0-35% in other studies. Prophylactic antiobiotics were used routinely in all cases to cover pre and post operative complications [18][19][20][21].

Conclusion
Pneumatic lithotripsy is found to be safe and effective procedure with overall success rate of 88.57% which is in line reported by other studies. The only appreciable disadvantages of Pneumatic lithotripsy were the limitations of pro rigidity leading to hematurea and potential proximal stone migration during treatment.