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Laser Fragmentation of Ureteral Calculi
Accepted 289
290
CO LASER VAPOURISATION OF URETHRAL STRICTURES. *T.A. Mc~icholas, *J. Calles, *S.G. Bown, London and Edinburgh, UK. (Presentation to be made by Dr. McNicholas). Endoscopic optical urethrotomy (OU) is a successful treatment for most simple short strictures ~f the urethra. In 10-25% results are unsatisfactory. In these cases, usually complex and long strictures, the only surgical treatment option remaining is urethroplasty. These complex strictures are generally characterised by extensive periurethral fibrosis. (Dilatation or OU cannot be expected to alter this). It has been suggested that removal of the fibrous plaque by CO2 laser vapourisation might improve results and reduce the need for urethroplasty. We have assessed this possibility by designing and testing an experimental CO2 laser cystoscope. Conventional endoscopic delivery of CO2 lasers is restricted to relatively wide devices allowing free propagation of the beam to the distal end and thus is not appropriate to the narrow bore urethroscope. We have therefore devised a novel approach utilising beam coupling at the proximal end to a narrow bore beam guiding tube that passes down the instrument channel of a modified small bore nephroscope. The outer diameter of the ceramic guide is 3 mm and the beam d.iameter ( 1-2mm) is maintained along its 250mm length to the distal tip. CO2 gas flow and suction are balanced to provide low pressure insufflation of the urethra and bladder. High transmission (approximately 95%) ensures up to 15w are available at the endoscope tip from a relatively small CO2 laser system. The system~s been tested on a canine model for urethral strictures. In 5 animals strictures have been
PROGRESS REPORT ON THE APPLICATION OF THE ENDOSCOPIC ULTRASONIC ASPIRATOR TO REMOVE PROSTATE, BLADDER TUMORS AND STONES IN HUMANS. Donald R.
vapourised without complications or recurrence in a foll0w
up of two months. CO2 laser vapourisation of urethral strictures using a small bore endoscope is possible. rurther modifications to improve performance are being made.
Krawitt, •'•Louis Katz, M.S.E.E., 1rDavid Wuchinich,M.S.E.E.,
Valhalla, N.Y. (Presented by Dr. Krawitt) The initial application of the use of ultrasonic aspiration on the prostate, bladder and stones in dogs was presented in 1984 during the
Atlanta meeting.
This was followed by the report
of early use of the ultrasonic endoscope in humans, at the N.Y. meeting last year. The objective of this subsequent work was to perfect an ultrasonic aspirator that would act as a scalpel to remove human prostate, bladder tumors and stones endoscopically in a manner which would prove more advantageous than the present method of electro-resection. The progressive step9 to incorporate all the assets of present day electro-resection of the
prostate and bladder plus the advantages of ultrasonic aspiration and the step by step development of the transurethral endoscopic instrument is explained. A series of human Subjects who were selected for transurethral ultrasonic aspiration of the prostate in the same way as thoseselected for electro-resection of the prostate were used. Complete pre-operative, intra-operative and postoperative monitoring was carried out. This included pre-operative I.V.P., cystoscopy, complete blood studies, continuous electrolyte monitoring pre, peri and post operatively. The results are presented arid the aforementioned advantages of continuous surgery, retrograde cutting, comparative reduction of intra-operative bleeding, post-operative care and overall results including hospitalization dime are also described.
291
292
CONTACT ND-YAC LASER IRRADIATION FOR BLADDER CANCER. H. Washidat H. Sakagamit Y. Iwaset S. Sasaki*and N. Daikuzonot Anjo Japan. (Presentation to be made by Dr. H. Washida) The Nd:YAG laser has been successfully applied in endoscopic urology for bladder cancer. The non-contact system, however, has serious limitations. We have succeeded in developing a new contact laser probe for transurethral endoscopic laser surgery. This special new probe, made from a ceramic material, has a diameter of 2.2 mm. Trans Urethral Laser Destruction (TULD) of bladder tumors has been performed 75 times in 54 cases with these contact probes. TULD has the advantages of accurate bloodless destruction of large tumors (over 3 cm.) with low laser wattage. In addition, these new probes provide less thermal damage to normal surrounding tissue than the non-contact approach. We are impressed that this newly developed contact system is supe_rior to previously developed non-contact laser instrumentation. Endoscopic color photographs of the procedure and serial follow up pictures will be shown.
LASER FRAGMENTATION OF URETERAL CALCULI. Stephen P. Dretler, Boston, MA (Presentation to be made by Dr. Dretler) The pulsed dye laser emitting at wavelength 504 NM for 1 microsecond at a frequency of 5-10 Hz transmitted via a 250 micron silica coated quartz fiber was used as the method of ureteral stone fragmentation in 60 patients from 9/85 to 10/86. The calculi treated were those not amenable to ESWL and too large for direct ureteroscopic extraction.
The technique used was
predominantly the rigid (9.5F) ureteroscope (56 patients). Preliminary ureteral dilatation was necessary in 60% of patients. The 250 micron laser fiber was placed inside a 4F ureteral catheter and passed via the working element of the 9.5F ureteroscope. If direct application of laser pulsation was successful in total stone fragmentation (60%), no other method was used. If the stone was hard and not easily fragmented (40%), a newly developed "laser basket" (a stone basket with a hole drilled along the length of the wire to allow a laser fiber) allowed partial fragmentation and extraction of the remaining portion.
In
4 patients, successful stone fragmentation was achieved using the laser via a flexible 9F ureteroscope. Fifty-eight of 60 patients had successful treatment. The advantages of the laser are its small fiber size, the absence of local tissue injury and the possibility for use of small calib0r flexible ureteral instruments for stone treatment. Specific cases in which it is clearly
superior to other methods include: stones impacted in the tunnel, large calculi in small caliber ureters, as a method of disimpaction prior to ESWL and for distal ureteral dislodgement of "steinstrasse".
176A
290
CO LASER VAPOURISATION OF URETHRAL STRICTURES. *T.A. Mc~icholas, *J. Calles, *S.G. Bown, London and Edinburgh, UK. (Presentation to be made by Dr. McNicholas). Endoscopic optical urethrotomy (OU) is a successful treatment for most simple short strictures ~f the urethra. In 10-25% results are unsatisfactory. In these cases, usually complex and long strictures, the only surgical treatment option remaining is urethroplasty. These complex strictures are generally characterised by extensive periurethral fibrosis. (Dilatation or OU cannot be expected to alter this). It has been suggested that removal of the fibrous plaque by CO2 laser vapourisation might improve results and reduce the need for urethroplasty. We have assessed this possibility by designing and testing an experimental CO2 laser cystoscope. Conventional endoscopic delivery of CO2 lasers is restricted to relatively wide devices allowing free propagation of the beam to the distal end and thus is not appropriate to the narrow bore urethroscope. We have therefore devised a novel approach utilising beam coupling at the proximal end to a narrow bore beam guiding tube that passes down the instrument channel of a modified small bore nephroscope. The outer diameter of the ceramic guide is 3 mm and the beam d.iameter ( 1-2mm) is maintained along its 250mm length to the distal tip. CO2 gas flow and suction are balanced to provide low pressure insufflation of the urethra and bladder. High transmission (approximately 95%) ensures up to 15w are available at the endoscope tip from a relatively small CO2 laser system. The system~s been tested on a canine model for urethral strictures. In 5 animals strictures have been
PROGRESS REPORT ON THE APPLICATION OF THE ENDOSCOPIC ULTRASONIC ASPIRATOR TO REMOVE PROSTATE, BLADDER TUMORS AND STONES IN HUMANS. Donald R.
vapourised without complications or recurrence in a foll0w
up of two months. CO2 laser vapourisation of urethral strictures using a small bore endoscope is possible. rurther modifications to improve performance are being made.
Krawitt, •'•Louis Katz, M.S.E.E., 1rDavid Wuchinich,M.S.E.E.,
Valhalla, N.Y. (Presented by Dr. Krawitt) The initial application of the use of ultrasonic aspiration on the prostate, bladder and stones in dogs was presented in 1984 during the
Atlanta meeting.
This was followed by the report
of early use of the ultrasonic endoscope in humans, at the N.Y. meeting last year. The objective of this subsequent work was to perfect an ultrasonic aspirator that would act as a scalpel to remove human prostate, bladder tumors and stones endoscopically in a manner which would prove more advantageous than the present method of electro-resection. The progressive step9 to incorporate all the assets of present day electro-resection of the
prostate and bladder plus the advantages of ultrasonic aspiration and the step by step development of the transurethral endoscopic instrument is explained. A series of human Subjects who were selected for transurethral ultrasonic aspiration of the prostate in the same way as thoseselected for electro-resection of the prostate were used. Complete pre-operative, intra-operative and postoperative monitoring was carried out. This included pre-operative I.V.P., cystoscopy, complete blood studies, continuous electrolyte monitoring pre, peri and post operatively. The results are presented arid the aforementioned advantages of continuous surgery, retrograde cutting, comparative reduction of intra-operative bleeding, post-operative care and overall results including hospitalization dime are also described.
291
292
CONTACT ND-YAC LASER IRRADIATION FOR BLADDER CANCER. H. Washidat H. Sakagamit Y. Iwaset S. Sasaki*and N. Daikuzonot Anjo Japan. (Presentation to be made by Dr. H. Washida) The Nd:YAG laser has been successfully applied in endoscopic urology for bladder cancer. The non-contact system, however, has serious limitations. We have succeeded in developing a new contact laser probe for transurethral endoscopic laser surgery. This special new probe, made from a ceramic material, has a diameter of 2.2 mm. Trans Urethral Laser Destruction (TULD) of bladder tumors has been performed 75 times in 54 cases with these contact probes. TULD has the advantages of accurate bloodless destruction of large tumors (over 3 cm.) with low laser wattage. In addition, these new probes provide less thermal damage to normal surrounding tissue than the non-contact approach. We are impressed that this newly developed contact system is supe_rior to previously developed non-contact laser instrumentation. Endoscopic color photographs of the procedure and serial follow up pictures will be shown.
LASER FRAGMENTATION OF URETERAL CALCULI. Stephen P. Dretler, Boston, MA (Presentation to be made by Dr. Dretler) The pulsed dye laser emitting at wavelength 504 NM for 1 microsecond at a frequency of 5-10 Hz transmitted via a 250 micron silica coated quartz fiber was used as the method of ureteral stone fragmentation in 60 patients from 9/85 to 10/86. The calculi treated were those not amenable to ESWL and too large for direct ureteroscopic extraction.
The technique used was
predominantly the rigid (9.5F) ureteroscope (56 patients). Preliminary ureteral dilatation was necessary in 60% of patients. The 250 micron laser fiber was placed inside a 4F ureteral catheter and passed via the working element of the 9.5F ureteroscope. If direct application of laser pulsation was successful in total stone fragmentation (60%), no other method was used. If the stone was hard and not easily fragmented (40%), a newly developed "laser basket" (a stone basket with a hole drilled along the length of the wire to allow a laser fiber) allowed partial fragmentation and extraction of the remaining portion.
In
4 patients, successful stone fragmentation was achieved using the laser via a flexible 9F ureteroscope. Fifty-eight of 60 patients had successful treatment. The advantages of the laser are its small fiber size, the absence of local tissue injury and the possibility for use of small calib0r flexible ureteral instruments for stone treatment. Specific cases in which it is clearly
superior to other methods include: stones impacted in the tunnel, large calculi in small caliber ureters, as a method of disimpaction prior to ESWL and for distal ureteral dislodgement of "steinstrasse".
176A