Urethral Calculi Managed With Transurethral Holmium Laser Ablation By Brady R. Walker and Blake D. Hamilton Salt Lake City, Utah
In situ Holmium laser lithotripsy is a safe, effective procedure for the treatment of impacted urethral stones. This procedure can be performed transurethrally as an outpatient with minimal tissue trauma and render patients stone free. The authors utilized this procedure in 2 patients whose anatomy did not allow the calculi to be manipulated into the urinary bladder in a retrograde manner. Because of its successful use elsewhere in the urinary tract, we believe that Holmium
laser lithotripsy may be the treatment of choice for impacted urethral stones. J Pediatr Surg 36:E16. Copyright © 2001 by W.B. Saunders Company.
RETHRAL CALCULI are uncommon, the majority are of upper tract or bladder origin and migrate into the urethra.1 Native urethral stones may develop with associated anatomic abnormalities or postsurgical changes. In general, the most common abnormalities associated with urethral stones include urethral strictures, diverticula, foreign bodies, and chronic infection.1-3 The frequently associated urethral abnormalities complicate management and may cause excessive urethral trauma. Treatment of urethral stones depends on the size, location, and mobility of the calculi. Historically, treatment consisted of either open removal or retrograde manipulation with intravesical fragmentation. We describe the use of a 365-m Holmium laser to fragment impacted urethral stones transurethrally. CASE REPORTS
Case 1 A 13-year-old boy with previous reconstruction of the exstrophyepispadias complex was found on plain abdominal roentgenogram to have a 20-mm urethral calculus (Fig 1). Preoperative retrograde urethrogram showed a large filling defect in the posterior urethra (Fig 2). Transurethral Holmium laser lithotripsy with a 365-m fiber through a pediatric cystoscope successfully fragmented this calculus in situ. The nidus for calculus formation was found to be a patch of hair-bearing epithelium that was included in his previous epispadias reconstruction. He was rendered stone free (Fig 2) and discharged home at the completion of the procedure.
From the Division of Urology, University of Utah School of Medicine, Salt Lake City, UT. Address reprint requests to Blake D. Hamilton, MD, University of Utah School of Medicine, Urology, 50 N Medical Dr, Room 3B-420, Salt Lake City, UT 84132. Copyright © 2001 by W.B. Saunders Company 1531-5037/01/3609-0031$35.00/0 doi:10.1053/jpsu.2001.26398 16
INDEX WORDS: Urethral calculi, Holmium laser, lithotripsy, urolithiasis.
A 10-year-old boy with anoxic brain injury and neurogenic bladder was found to have a 10-mm asymptomatic prostatic urethral stone. He also had a history of multiple recurrent urinary tract infections and urinary stasis. Cystoscopic examination showed an impacted posterior urethral stone that was fragmented completely with transurethral in situ Holmium laser lithotripsy. This patient also was rendered stone free and treated as an outpatient.
Urethral calculi are quite uncommon and are the least common form of urinary calculus disease in the United States. These stones can be classified as either migrant or native with the former being responsible for roughly 90% of all stones.1 Migrant stones originate in the bladder or upper tracts and generally become impacted in the posterior urethra. The presentation generally is one of acute urinary retention with subsequent edema of the posterior urethra.1,3 In contrast, native urethral stones form in the urethra and are associated with strictures, urethral diverticula, chronic infection, and urethral foreign bodies.1-3 The presentation of native stones may be more subtle because this appears to be a gradual, chronic process. We encountered 2 pediatric patients with impacted posterior urethral calculi. Risk factors in these patients included hair-bearing epithelium in a boy who had undergone numerous reconstructive procedures for his exstrophy-epispadias complex and in a boy with a neurogenic bladder. Management options in treating these patients depend on the size, location and mobility of the stones. Historically, treatment options consisted primarily of open surgical removal or retrograde manipulation and intravesical fragmentation. We chose to perform in situ Holmium laser lithotripsy in our patients because of the Journal of Pediatric Surgery, Vol 36, No 9 (September), 2001: E16
HOLMIUM LASER FOR URETHRAL CALCULI
perceived difficulty in manipulating these into the urinary bladder. The Holmium laser has been used to treat renal, ureteral, and bladder stones safely and effectively.4-6 Utilizing a pediatric cystoscope and a 365-m laser fiber we were able to treat 2 patients with impacted posterior urethral calculi. In both patients transurethral in situ Holmium laser lithotripsy was performed safely in an outpatient setting rendering both patients stone free. Holmium laser lithotripsy is an excellent alternative for treating urethral stones. It is especially useful in patients with anatomic constraints or significant edema, which precludes retrograde manipulation into the urinary bladder. REFERENCES
Fig 1. Preoperative radiograph shows a 20-mm radioopaque posterior urethral calculus.
1. Paulk SC, Khan AU, Malek RS, et al: Urethral calculi. J Urol 116:436-439, 1976 2. Koga S, Matsuoka AM, Ohyama C: Urethral calculi. Br J Urol 65:288-289, 1990 3. Amin AA: Urethral Calculi. Br J Urol 45:192-199, 1973 4. Scarpa RM, De Lisa A, Porru D, et al: Holmium:YAG laser ureterolithotripsy. Eur Urol 35:233-238, 1999 5. Grasso M, Chalik Y: Principles and applications of laser lithotripsy: Experience with the Holmium laser lithotrite. J Clin Laser Med Surg 16:3-7, 1998 6. McIver BD, Griffin KP, Harris JM, et al: Cystoscopic Holmium lithotripsy of large bladder calculi. Tech Urol 2:65-67, 1996
Fig 2. (A) Intraoperative retrograde urethrogram shows a 20-mm ﬁlling defect in the posterior urethra. (B) Postoperative retrograde urethrogram shows no evidence of ﬁlling defects or residual stone.