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Sample records for endoscopic laser lithotripsy

  1. Endoscopically controlled laser lithotripsy of sialoliths

    NASA Astrophysics Data System (ADS)

    Gundlach, Peter; Hopf, Juergen U. G.; Linnarz, Marietta; Leege, Nils; Scherer, Hans H.; Tschepe, Johannes; Mueller, Gerhard J.

    1992-08-01

    Among the diseases of the major salivary glands, sialolithiasis is a frequent clinical picture. Until now the condition has nearly always had to be treated surgically. In rare cases, discharge can be achieved by acid stimulation of secretion. If located distally in the excretory duct, concrements may be removed by enoral lancing. If it is close to glands, e.g., in the knee of Wharton's duct or in the ductal part of the submandibular gland, extirpation of the gland including the stone is unavoidable. Besides wound healing problems and the occurrence of salivary fistulas, the main risk of surgery is injury to the nerves around the major salivary glands, e.g., the n. facialis or one of its branches, the n. hypoglossus, or the n. lingualis with consecutive paresis. Based on the clinical results of lithotripsy by laser-induced shock waves (LIL) applied to renal stones and ureteroliths as well as bilary duct and pancreas stones, we investigated the suitability of endoscopically controlled laser therapy for sialolithiasis.

  2. Lithotripsy

    MedlinePlus

    ... Laser lithotripsy; Percutaneous lithotripsy; Endoscopic lithotripsy; ESWL; Renal calculi-lithotripsy ... Lingeman JE. Surgical management of upper urinary tract calculi. In: Wein AJ, ed. Campbell-Walsh Urology . 10th ...

  3. Endoscopic Holmium:YAG laser-assisted lithotripsy: A Preliminary Report.

    PubMed

    Su, C H; Lee, K S; Tseng, T M; Hung, S H

    2015-01-01

    Laser-assisted lithotripsy under sialendoscopy has the potential to overcome the limitations of traditional sialendoscopic lithotripsy when facing salivary stones. In this preliminary study, we report our experience with Holmium:YAG laser-assisted lithotripsy. Data from 11 Asian patients receiving sialendoscopies for laser-assisted lithotripsy performed in our department from August 2013 to June 2014 were recorded and reviewed. A total of 18 procedures were performed in 11 Taiwanese patients with symptoms of obstructive sialoadenitis who were diagnosed with sialolithiasis. The sizes of the stones ranged between 3 mm and 13 mm. The endoscopic lithotomy procedures were performed in all 11 patients, and stone fragmentation with the Holmium:YAG laser was done successfully in all patients. All patients were followed for a minimum of 3 months, and there was no evidence of complications or recurrences over the follow up period. The Holmium:YAG laser allowed successful fragmentation of stones in all 11 patients. Our experience with this procedure supports the use of Holmium:YAG laser-assisted lithotripsy through sialendoscopy in Asian patients.

  4. Percutaneous endoscopic holmium laser lithotripsy for management of complicated biliary calculi.

    PubMed

    Healy, Kelly; Chamsuddin, Abbas; Spivey, James; Martin, Louis; Nieh, Peter; Ogan, Kenneth

    2009-01-01

    Advances in endoscopic techniques have transformed the management of urolithiasis. We sought to evaluate the role of such urological interventions for the treatment of complex biliary calculi. We conducted a retrospective review of all patients (n=9) undergoing percutaneous holmium laser lithotripsy for complicated biliary calculi over a 4-year period (12/2003 to 12/2007). All previously failed standard techniques include ERCP with sphincterotomy (n=6), PTHC (n=7), or both of these. Access to the biliary system was obtained via an existing percutaneous transhepatic catheter or T-tube tracts. Endoscopic holmium laser lithotripsy was performed via a flexible cystoscope or ureteroscope. Stone clearance was confirmed intra- and post-operatively. A percutaneous transhepatic drain was left indwelling for follow-up imaging. Mean patient age was 65.6 years (range, 38 to 92). Total stone burden ranged from 1.7 cm to 5 cm. All 9 patients had stones located in the CBD, with 2 patients also having additional stones within the hepatic ducts. All 9 patients (100%) were visually stone-free after one endoscopic procedure. No major perioperative complications occurred. Mean length of stay was 2.4 days. At a mean radiological follow-up of 5.4 months (range, 0.5 to 21), no stone recurrence was noted. Percutaneous endoscopic holmium laser lithotripsy is a minimally invasive alternative to open salvage surgery for complex biliary calculi refractory to standard approaches. This treatment is both safe and efficacious. Success depends on a multidisciplinary approach.

  5. Endoscopically controlled laser lithotripsy of salivary gland calculi and the problem of fiber wear

    NASA Astrophysics Data System (ADS)

    Tschepe, Johannes; Gundlach, Peter; Leege, Nils; Hopf, Juergen U. G.; Mueller, Gerhard J.; Scherer, Hans H.

    1992-08-01

    Seventy-three patients suffering from sialolithiasis were treated by endoscopically controlled, laser-induced lithotripsy (LIL). The non-sedated patients were treated under local anaesthetic with specially developed endoscopes with a diameter < 1.8 mm. A laser fiber was then positioned on the concrement which was finally fragmented while being monitored using a pulsed excimer laser (308 nm), a dye laser (504 nm), and an Alexandrite laser (755 nm). In all cases a complete fragmentation of the stone was achieved. This approach to laser lithotripsy of salivary gland calculi with endoscopic monitoring represents a novel method which permits an out-patient treatment under local anaesthetic with a minimum inconvenience to the patient. In `in vitro' experiments the effectiveness of the stone destruction (plasma formation rate, the number of pulses required to fragment the stone, and fragment size) were tested. The quantitative assessment of the fiber end surface during direct contact and the determination of the shape and size of the broken fiber pieces have been tested. A possibility to avoid the fiber wear was developed. It's called `Index Matching' and needs a special endoscopic integrated flushing system.

  6. Percutaneous Endoscopic Holmium Laser Lithotripsy for Management of Complicated Biliary Calculi

    PubMed Central

    Healy, Kelly; Chamsuddin, Abbas; Spivey, James; Martin, Louis; Nieh, Peter

    2009-01-01

    Background and Objectives: Advances in endoscopic techniques have transformed the management of urolithiasis. We sought to evaluate the role of such urological interventions for the treatment of complex biliary calculi. Methods: We conducted a retrospective review of all patients (n=9) undergoing percutaneous holmium laser lithotripsy for complicated biliary calculi over a 4-year period (12/2003 to 12/2007). All previously failed standard techniques include ERCP with sphincterotomy (n=6), PTHC (n=7), or both of these. Access to the biliary system was obtained via an existing percutaneous transhepatic catheter or T-tube tracts. Endoscopic holmium laser lithotripsy was performed via a flexible cystoscope or ureteroscope. Stone clearance was confirmed intra- and postoperatively. A percutaneous transhepatic drain was left indwelling for follow-up imaging. Results: Mean patient age was 65.6 years (range, 38 to 92). Total stone burden ranged from 1.7 cm to 5 cm. All 9 patients had stones located in the CBD, with 2 patients also having additional stones within the hepatic ducts. All 9 patients (100%) were visually stone-free after one endoscopic procedure. No major perioperative complications occurred. Mean length of stay was 2.4 days. At a mean radiological follow-up of 5.4 months (range, 0.5 to 21), no stone recurrence was noted. Conclusions: Percutaneous endoscopic holmium laser lithotripsy is a minimally invasive alternative to open salvage surgery for complex biliary calculi refractory to standard approaches. This treatment is both safe and efficacious. Success depends on a multidisciplinary approach. PMID:19660213

  7. Endoscopically controlled electrohydraulic intracorporal shock wave lithotripsy as a new therapy for sialolithiasis: first clinical experiences in comparison to the results of laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Koenigsberger, Rainer; Feyh, Jens; Goetz, Alwin E.; Kastenbauer, E.

    1992-06-01

    The endoscopically controlled electrohydraulic shock wave lithotripsy (EISL) of salivary stones was performed on 29 patients with submandibular duct stones as a new non-surgical treatment of sialolithiasis. Under local anesthesia, a flexible fiberscope with an additional probe to generate shock waves is placed into the submandibular duct. Under endoscopic monitoring the fiberscope is advanced until the stone is identified. For stone disintegration, the probe must be situated 1 mm in front of the concrement. The fragmentation itself is performed by pressure waves generated by a sparkover at the tip of the probe. By means of the endoscopically controlled shock wave lithotripsy (EISL), it was possible to achieve complete stone fragmentation in 20 of 29 patients without serious side effects. In 3 patients only partial stone fragmentation could be achieved due to the stone quality. The endoscopically controlled electrohydraulic intracorporal shock wave lithotripsy (EISL) represents a novel non-invasive therapy for endoscopically accessible salivary gland stones. This therapy is performed on an outpatient basis with little inconvenience to the patient. The advantage in comparison to the endoscopically controlled laser lithotripsy will be discussed.

  8. Direct cholangioscopy-based holmium laser lithotripsy of difficult bile duct stones by using an ultrathin upper endoscope without a separate biliary irrigating catheter.

    PubMed

    Lee, Tae Yoon; Cheon, Young Koog; Choe, Won Hyeok; Shim, Chan Sup

    2012-01-01

    We investigated the impact of direct peroral cholangioscopy (POC)-based holmium laser lithotripsy using an ultrathin endoscope with direct irrigation via a 2-mm-diameter working channel to remove difficult common bile duct (CBD) stones without a separate biliary catheter. Few clinical studies have reported the successful removal of difficult CBD stones by direct POC-based laser lithotripsy using an ultrathin upper endoscope. Previous studies used a separate biliary catheter to ensure continuous irrigation. Ten patients (6 males; mean age 63.3 years) with difficult CBD stones who were not amenable to conventional endoscopic procedures were examined. Direct POC using an ultrathin upper endoscope was performed in all patients. Holmium laser lithotripsy with direct saline irrigation via the operating channel of an ultrathin endoscope was performed until stone fragments were captured in a basket. The overall success rate of bile duct clearance was 90% (9 of 10 patients) and the mean number of treatment sessions was 1.2 (range, 1-2). Mechanical lithotripsy was performed to complete stone removal in one patient (10%) who had a distal CBD stricture. One patient experienced mild cholangitis following laser lithotripsy. Holmium laser lithotripsy under direct POC using an ultrathin upper endoscope may be an effective and safe technique for removal of difficult CBD stones. Direct irrigation via the 2-mm-diameter working channel of the ultrathin endoscope provides sufficient fluid medium and affords good endoscopic viewing to assure stone fragmentation without any need for a separate biliary catheter.

  9. Percutaneous transhepatic endoscopic holmium laser lithotripsy for intrahepatic and choledochal biliary stones.

    PubMed

    Ierardi, Anna Maria; Fontana, Federico; Petrillo, Mario; Floridi, Chiara; Cocozza, Eugenio; Segato, Sergio; Abou El Abbas, Hatem; Mangano, Alberto; Carrafiello, Gianpaolo; Dionigi, Renzo

    2013-01-01

    To report our experience in treating complicated biliary calculi by percutaneous transhepatic endoscopic biliary holmium laser lithotripsy (PTBL). Ten symptomatic patients with intrahepatic or common bile duct calculi underwent PTBL. Six of these patients had previously undergone unsuccessful endoscopic treatment; four patients were declared not suitable for endoscopic procedure. PTBL was performed with a flexible choledochoscopy inserted by way of the percutaneous access sheath. A holmium laser was used to fragment the biliary stones. Sphincteroplasty was performed when considered necessary and an occlusion balloon for the clearance of common bile duct (CBD) calculi was used when continuous warm saline irrigation at high pressure was not sufficient. Clinical follow up was performed by the referring physician. Technical success, clinical success and complications were evaluated. Technical success rate was 100%. The overall clinical success rate was 100%. No patients underwent additional procedures for retained stones or developed de novo strictures or other complications related to the procedure. Hospital stay was no more than 4 days after the procedure. Duration of follow-up was 6-25 months (mean 12.6). One patient died from unrelated causes. During this period, no recurrence and/or complications related to procedure were observed. No major complications were registered. Minor complications like temporary abdominal pain were considered not significant by the patients. Complicated or large biliary calculi can be treated successfully using PTBL. In selected patients, this approach should become the first choice of treatment after other treatments are rejected. Copyright © 2013 Elsevier Ltd and Surgical Associates Ltd. All rights reserved.

  10. Percutaneous Transhepatic Endoscopic Holmium Laser Lithotripsy for Intrahepatic and Choledochal Biliary Stones

    SciTech Connect

    Rimon, Uri; Kleinmann, Nir; Bensaid, Paul; Golan, Gil; Garniek, Alexander; Khaitovich, Boris; Winkler, Harry

    2011-12-15

    Purpose: To report our approach for treating complicated biliary calculi by percutaneous transhepatic endoscopic biliary holmium laser lithotripsy (PTBL). Patients and Methods: Twenty-two symptomatic patients (11 men and 11 women, age range 51 to 88 years) with intrahepatic or common bile duct calculi underwent PTBL. Nine patients had undergone previous gastrectomy and small-bowel anastomosis, thus precluding endoscopic retrograde cholangiopancreatography. In the other 13 patients, stone removal attempts by ERCP failed due to failed access or very large calculi. We used a 7.5F flexible ureteroscope and a 200-{mu}m holmium laser fiber by way of a percutaneous transhepatic tract, with graded fluoroscopy, to fragment the calculi with direct vision. Balloon dilatation was added when a stricture was seen. The procedure was performed with the patient under general anaesthesia. A biliary drainage tube was left at the end of the procedure. Results: All stones were completely fragmented and flushed into the small bowel under direct vision except for one patient in whom the procedure was aborted. In 18 patients, 1 session sufficed, and in 3 patients, 2 sessions were needed. In 7 patients, balloon dilatation was performed for benign stricture after Whipple operation (n = 3), for choledochalenteric anastomosis (n = 3), and for recurrent cholangitis (n = 1). Adjunctive 'balloon push' (n = 4) and 'rendezvous' (n = 1) procedures were needed to completely clean the biliary tree. None of these patients needed surgery. Conclusion: Complicated or large biliary calculi can be treated successfully using PTBL. We suggest that this approach should become the first choice of treatment before laparoscopic or open surgery is considered.

  11. Percutaneous transhepatic endoscopic holmium laser lithotripsy for intrahepatic and choledochal biliary stones.

    PubMed

    Rimon, Uri; Kleinmann, Nir; Bensaid, Paul; Golan, Gil; Garniek, Alexander; Khaitovich, Boris; Winkler, Harry

    2011-12-01

    To report our approach for treating complicated biliary calculi by percutaneous transhepatic endoscopic biliary holmium laser lithotripsy (PTBL). Twenty-two symptomatic patients (11 men and 11 women, age range 51 to 88 years) with intrahepatic or common bile duct calculi underwent PTBL. Nine patients had undergone previous gastrectomy and small-bowel anastomosis, thus precluding endoscopic retrograde cholangiopancreatography. In the other 13 patients, stone removal attempts by ERCP failed due to failed access or very large calculi. We used a 7.5F flexible ureteroscope and a 200-μm holmium laser fiber by way of a percutaneous transhepatic tract, with graded fluoroscopy, to fragment the calculi with direct vision. Balloon dilatation was added when a stricture was seen. The procedure was performed with the patient under general anaesthesia. A biliary drainage tube was left at the end of the procedure. All stones were completely fragmented and flushed into the small bowel under direct vision except for one patient in whom the procedure was aborted. In 18 patients, 1 session sufficed, and in 3 patients, 2 sessions were needed. In 7 patients, balloon dilatation was performed for benign stricture after Whipple operation (n = 3), for choledochalenteric anastomosis (n = 3), and for recurrent cholangitis (n = 1). Adjunctive "balloon push" (n = 4) and "rendezvous" (n = 1) procedures were needed to completely clean the biliary tree. None of these patients needed surgery. Complicated or large biliary calculi can be treated successfully using PTBL. We suggest that this approach should become the first choice of treatment before laparoscopic or open surgery is considered.

  12. A comparison of efficacies of holmium YAG laser, and pneumatic lithotripsy in the endoscopic treatment of ureteral stones

    PubMed Central

    Akdeniz, Ekrem; İrkılata, Lokman; Demirel, Hüseyin Cihan; Saylık, Acun; Bolat, Mustafa Suat; Şahinkaya, Necmettin; Zengin, Mehmet; Atilla, Mustafa Kemal

    2014-01-01

    Objective: We aimed to compare the effectiveness of holmium YAG laser and pneumatic lithotripsy in the treatment of ureteral stones. Material and methods: A total of 216 patients who had established indications of ureteroscopy between November 2011 and June 2012 were included in this study. Patients’ files were retrospectively reviewed by dividing cases as groups that underwent pneumatic (PL) or laser lithotripsy (LL) procedures. Age, sex, stone burden and localization, duration of follow-up, operative times were evaluated. Stone-free rates were evaluated by ureteroscopical examination, postoperative scout films and ultrasonography. Results: Group PL consisted of 109 and group LL of 107 patients. Median age was 43.93±15.94 years in Group PL and 46.15±14.54 years in Group LL. Male to female ratio, stone burden and localization were similar for both groups. Overall success rate was 89.9% in Group PL and 87.9% in Group LL, respectively (p<0.791). With the aid of additional procedures, success rate was 100% for both groups at the end of the first month. Groups were not different as for operative time, rate of insertion of an ureteral catheter and its removal time. Hospitalization period was apparently somewhat shorter in Group LL (p=0.00). Conclusion: Pneumatic lithotripsy can be as efficacious as laser lithotripsy and be used safely in the endoscopic management of ureteral stone. In comparison of both methods, we detected no differences as to operative time, success of operation and the time to removal of the catheter, however, hospitalization period was shorter in Group LL. PMID:26328167

  13. A comparison of efficacies of holmium YAG laser, and pneumatic lithotripsy in the endoscopic treatment of ureteral stones.

    PubMed

    Akdeniz, Ekrem; İrkılata, Lokman; Demirel, Hüseyin Cihan; Saylık, Acun; Bolat, Mustafa Suat; Şahinkaya, Necmettin; Zengin, Mehmet; Atilla, Mustafa Kemal

    2014-09-01

    We aimed to compare the effectiveness of holmium YAG laser and pneumatic lithotripsy in the treatment of ureteral stones. A total of 216 patients who had established indications of ureteroscopy between November 2011 and June 2012 were included in this study. Patients' files were retrospectively reviewed by dividing cases as groups that underwent pneumatic (PL) or laser lithotripsy (LL) procedures. Age, sex, stone burden and localization, duration of follow-up, operative times were evaluated. Stone-free rates were evaluated by ureteroscopical examination, postoperative scout films and ultrasonography. Group PL consisted of 109 and group LL of 107 patients. Median age was 43.93±15.94 years in Group PL and 46.15±14.54 years in Group LL. Male to female ratio, stone burden and localization were similar for both groups. Overall success rate was 89.9% in Group PL and 87.9% in Group LL, respectively (p<0.791). With the aid of additional procedures, success rate was 100% for both groups at the end of the first month. Groups were not different as for operative time, rate of insertion of an ureteral catheter and its removal time. Hospitalization period was apparently somewhat shorter in Group LL (p=0.00). Pneumatic lithotripsy can be as efficacious as laser lithotripsy and be used safely in the endoscopic management of ureteral stone. In comparison of both methods, we detected no differences as to operative time, success of operation and the time to removal of the catheter, however, hospitalization period was shorter in Group LL.

  14. Outcome analysis of holmium laser and pneumatic lithotripsy in the endoscopic management of lower ureteric calculus in pediatric patients: a prospective study

    PubMed Central

    Jhanwar, Ankur; Bansal, Ankur; Sankhwar, Satyanarayan; Kumar, Manoj; Kanodia, Gautam; Prakash, Gaurav

    2016-01-01

    ABSTRACT Objective: To analyse outcomes of holmium laser and pneumatic lithotripsy in treatment of lower ureteric calculus in pediatric patients. Materials and methods: Prospective study conducted between August 2013 and July 2015. Inclusion criteria were lower ureteric calculus with stone size ≤1.5cms. Exclusion criteria were other than lower ureteric calculus, stone size ≥1.5cms, congenital renal anomalies, previous ureteral stone surgery. Patients were divided into two groups. Group A underwent pneumatic and group B underwent laser lithotripsy procedure. Patient's baseline demographic and peri-operative data were recorded and analysed. Post operatively X-ray/ultrasound KUB (Kidney, ureter and bladder) was performed to assess stone free status. Results: A total of 76 patients who met the inclusion criteria to ureteroscopic intracorporeal lithotripsy were included. Group A and B included 38 patients in each. Mean age was 12.5±2.49 in Group A and 11.97±2.74 years in Group B respectively (p=0.38). Overall success rate was 94.73% in Group A and 100% in Group B, respectively (p=0.87). Conclusion: Holmium Laser lithotripsy is as efficacious as pneumatic lithotripsy and can be used safely for the endoscopic management of lower ureteric calculus in pediatric patients. However, holmium laser requires more expertise and it is a costly alternative. PMID:27622283

  15. Thulium Fiber Laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Blackmon, Richard Leious, Jr.

    The Thulium Fiber Laser (TFL) has been studied as a potential alternative to the conventional Holmium:YAG laser (Ho:YAG) for the treatment of kidney stones. The TFL is more ideally suited for laser lithotripsy because of the higher absorption coefficient of the emitted wavelength in water, the superior Gaussian profile of the laser beam, and the ability to operate at arbitrary temporal pulse profiles. The higher absorption of the TFL by water helps translate into higher ablation of urinary stones using less energy. The Gaussian spatial beam profile allows the TFL to couple into fibers much smaller than those currently being used for Ho:YAG lithotripsy. Lastly, the ability of arbitrary pulse operation by the TFL allows energy to be delivered to the stone efficiently so as to avoid negative effects (such as burning or bouncing of the stone) while maximizing ablation. Along with these improvements, the unique properties of the TFL have led to more novel techniques that have currently not been used in the clinic, such as the ability to control the movement of stones based on the manner in which the laser energy is delivered. Lastly, the TFL has led to the development of novel fibers, such as the tapered fiber and removable tip fiber, to be used for lithotripsy which can lead to safer and less expensive treatment of urinary stones. Overall, the TFL has been demonstrated as a viable alternative to the conventional Ho:YAG laser and has the potential to advance methods and tools for treatment of kidney stones.

  16. Calculus fragmentation in laser lithotripsy.

    PubMed

    Welch, A J; Kang, H W; Lee, H; Teichman, J M H

    2004-03-01

    The intracorporeal treatment of urinary calculi with lasers is presented, which describes laser-calculus interactions associated with lithotripsy. Reliable fragmentation of calculi with diverse compositions and minimal collateral tissue damage are primarily contingent upon laser parameters (wavelength, pulse duration, and pulse energy) and physical properties of calculi (optical, mechanical, and chemical). The pulse duration governs the dominant mechanism in calculi fragmentation, which is either photothermal or photoacoustical/photomechanical. Lasers with long pulse durations (i.e. > tens of micros) induce a temperature rise in the laser-affected zone with minimal acoustic waves; material is removed by means of vaporization, melting, mechanical stress, and/or chemical decomposition. Short-pulsed laser ablation (i.e. < 10 micros), on the other hand, produces shock waves, and the resultant mechanical energy fragments calculi. Work continues throughout the world to evaluate the feasibility of advanced lasers in lithotripsy and to optimize laser parameters and light delivery systems pertinent to efficient fragmentation of calculi.

  17. Bubble Dynamics in Laser Lithotripsy

    NASA Astrophysics Data System (ADS)

    Mohammadzadeh, Milad; Martinez Mercado, Julian; Ohl, Claus-Dieter

    2015-12-01

    Laser lithotripsy is a medical procedure for fragmentation of urinary stones with a fiber guided laser pulse of several hundred microseconds long. Using high-speed photography, we present an in-vitro study of bubble dynamics and stone motion induced by Ho:YAG laser lithotripsy. The experiments reveal that detectable stone motion starts only after the bubble collapse, which we relate with the collapse-induced liquid flow. Additionally, we model the bubble formation and dynamics using a set of 2D Rayleigh-Plesset equations with the measured laser pulse profile as an input. The aim is to reduce stone motion through modification of the temporal laser pulse profile, which affects the collapse scenario and consequently the remnant liquid motion.

  18. Successful endoscopic treatment of colonic gallstone ileus using electrohydraulic lithotripsy.

    PubMed

    Zielinski, Martin D; Ferreira, Lincoln E; Baron, Todd H

    2010-03-28

    The surgical management of gallstone ileus is complex and potentially highly morbid. Initial management requires enterolithotomy and is generally followed by fistula resection at a later date. There have been reports of gallstone extraction using various endoscopic modalities to relieve the obstruction, however, to date, there has never been a published case of endoscopic stone extraction from the colon using electrohydraulic lithotripsy. In this report, we present the technique employed to successfully perform an electrohydraulic lithotripsy for removal of a large gallstone impacted in the sigmoid colon. A cavity was excavated in an obstructing 4.1 cm lamellated stone in the sigmoid colon using electrohydraulic lithotripsy. A screw stent retractor and stent extractor bored a larger lumen which allowed for guidewire advancement and stone fracture via serial pneumatic balloon dilatation. The stone fragments were removed. Electrohydraulic lithotripsy is a safe and effective method to treat colonic obstruction in the setting of gallstone ileus.

  19. Combined external lithotripsy and endoscopic techniques for advanced sialolithiasis cases.

    PubMed

    Nahlieli, Oded; Shacham, Rachel; Zaguri, Ami

    2010-02-01

    To assess a combined external lithotripsy-sialoendoscopy method developed for advanced salivary gland sialolithiasis. A total of 94 patients (43 males and 51 females) underwent these treatment methods. Of these 94 patients, 60 had pathologic features in the submandibular gland and 34 in the parotid gland. A miniature external lithotripter was used, combined with multifunctional sialoendoscopes and endoscopic-assisted techniques, to achieve effective removal/elimination of the stones in these difficult cases. Total elimination of the stone using lithotripsy alone was achieved in 32% of the cases; in 29%, intraductal endoscopic assistance was needed. In the remaining 39%, the removal of a stone was achieved with the help of an endoscopy-assisted extraductal approach (37 cases). At 6 months of follow-up, all patients who had undergone lithotripsy or lithotripsy plus intraductal endoscopy had an absence of symptoms. Of the 37 patients who had undergone an endoscopy-assisted extraductal approach, 35 (95%) remained asymptomatic. Lithotripsy plus intraductal or extraductal endoscopic treatment of sialolithiasis is a highly effective surgical method of eliminating/removing salivary stones, especially those attached to the surrounding tissue and in the secondary ducts. This method helps to avoid resection of the salivary glands and represents an additional development of minimal invasive surgical techniques. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Erbium: YAG laser lithotripsy mechanism.

    PubMed

    Chan, Kin Foong; Lee, Ho; Teichman, Joel M H; Kamerer, Angela; McGuff, H Stan; Vargas, Gracie; Welch, Ashley J

    2002-08-01

    We tested the hypothesis that the mechanism of long pulse erbium:YAG laser lithotripsy is photothermal. Human urinary calculi were placed in deionized water and irradiated with erbium:YAG laser energy delivered through a sapphire optical fiber. Erbium:YAG bubble dynamics were visualized with Schlieren flash photography and correlated to acoustic emissions measured by a polyvinylidene fluoride needle hydrophone. The sapphire fiber was placed either parallel or perpendicular to the calculus surface to assess the contribution of acoustic transients to fragmentation. Stones were irradiated using desiccated stone irradiated in air, hydrated stone irradiated in air and hydrated stone irradiated in water. Ablation crater sizes were compared. Uric acid stones were irradiated in water and the water was assayed for cyanide. During the early phase of vapor bubble expansion, acoustic transients had minimal effects on calculus fragmentation. Fragmentation occurred due to direct absorption of laser energy transmitted to the calculus through the vapor channel between the sapphire fiber tip and calculus. The forward axial expansion of the bubble occurred more rapidly than the radial expansion. A parallel oriented fiber on the calculus surface produced no fragmentation but generated larger amplitude acoustic transients compared to perpendicular orientation. In perpendicular orientation the erbium:YAG laser did not generate any collapse acoustic waves but fragmentation occurred. Crater width was greatest for desiccated stones irradiated in air (p <0.03). Cyanide production increased as erbium:YAG irradiation of uric acid calculi increased, (r2 = 0.98). The erbium:YAG laser fragments stones through a photothermal mechanism.

  1. Therapy and Prevention of Postoperative Urosepsis of Ureter Endoscopic Lithotripsy for Non-infection.

    PubMed

    Shen, Jun; Sun, Fa; Chen, Fang-Min; Wu, Zhi-Ping; Li, Sheng-Wen

    2016-03-20

    Objective To analyze the risk factors causing postoperative urosepsis in ureter endoscopic lithotripsy without infection preoperatively, in order to make a more effective and safer preventive and therapeutic strategy.Methods From January 2010 to January 2015, 5 ureteral calculus patients undergoing ureter endoscopic lithotripsy with holmium laser were retrospectively enrolled in this clinical study. These patients suffered urosepsis postoperatively confirmed by the clinical presentations and laboratory Results, while they had no infection in their blood and urine preoperatively. Without delay, 5 patients were treated by anti-inflammation and anti-shock.Results The vasopressor drug was stopped gradually after 12-36 hours. The body temperature was recovered to normal in 2 or 3 days, and the blood and urine test Results were not abnormal in 7 days. At last, 5 patients were all cured.Conclusions Stone and operation themselves are potential factors to cause urosepsis after ureter endoscopic lithotripsy. Especially for patients who had not presented infection preoperatively, careful preparation preoperatively, corrective manipulation, low pressure irrigation, drainage and controlling time during operation, and early diagnosis, appropriate treatment postoperatively are the key to cure and prevent urosepsis.

  2. Prospective randomized controlled trial comparing laser lithotripsy with pneumatic lithotripsy in miniperc for renal calculi.

    PubMed

    Ganesamoni, Raguram; Sabnis, Ravindra B; Mishra, Shashikant; Parekh, Narendra; Ganpule, Arvind; Vyas, Jigish B; Jagtap, Jitendra; Desai, Mahesh

    2013-12-01

    The energy source used for stone fragmentation is important in miniperc. In this study, we compared the stone fragmentation characteristics and outcomes of laser lithotripsy and pneumatic lithotripsy in miniperc for renal calculi. After Institutional Review Board approval, 60 patients undergoing miniperc for renal calculi of 15 to 30 mm were equally randomized to laser and pneumatic lithotripsy groups. Miniperc was performed using 16.5F Karl Storz miniperc sheath and a 12F nephroscope. Laser lithotripsy was performed using a 550-μm laser fiber and 30 W laser with variable settings according to the need. Pneumatic lithotripsy was performed using the EMS Swiss lithoclast. Patient demographics, stone characteristics, intraoperative parameters, and postoperative outcomes were analyzed. The baseline patient demographics and stone characteristics were similar in both groups. The total operative time (P = 0.433) and fragmentation time (P=0.101) were similar between the groups. The surgeon assessed that the Likert score (1 to 5) for fragmentation was similar in both groups (2.1 ± 0.8 vs 1.9 ± 0.9, P=0.313). Stone migration was lower with the laser (1.3 ± 0.5 vs 1.7 ± 0.8, P=0.043), and fragment removal was easier with the laser (1.1 ± 0.3 vs 1.7 ± 1.1, P=0.011). The need for fragment retrieval using a basket was significantly more in the pneumatic lithotripsy group (10% vs 37%, P=0.002). The hemoglobin drop, complication rates, auxiliary procedures, postoperative pain, and stone clearance rates were similar between the groups (P>0.2). Both laser lithotripsy and pneumatic lithotripsy are equally safe and efficient stone fragmentation modalities in miniperc. Laser lithotripsy is associated with lower stone migration and easier retrieval of the smaller fragments it produces.

  3. Endoscopic removal of an enterolith causing afferent loop syndrome using electrohydraulic lithotripsy.

    PubMed

    Kim, Hwa Jong; Moon, Jong Ho; Choi, Hyun Jong; Koo, Hyun Cheol; Park, Sung Jin; Cheon, Young Koog; Cho, Young Deok; Lee, Moon Sung; Shim, Chan Sup

    2010-07-01

    Electrohydraulic lithotripsy is a very useful method for fragmenting biliary stones and it can be used for endoscopic removal of difficult biliary stones. Acute afferent loop syndrome induced by enterolith is very rare, and surgical treatment is the usual choice for this condition. We describe a patient with acute afferent loop syndrome, which was induced by an enterolith after a Billroth II gastrectomy. We used electrohydraulic lithotripsy to endoscopically remove the enterolith.

  4. Endoscopic-assisted electrohydraulic shockwave lithotripsy in standing sedated horses.

    PubMed

    Röcken, Michael; Fürst, Anton; Kummer, Martin; Mosel, Gesine; Tschanz, Theo; Lischer, Christoph J

    2012-07-01

    To report use of transendoscopic electrohydraulic shockwave lithotripsy for fragmentation of urinary calculi in horses. Case series. Male horses (n = 21). Fragmentation of cystic calculi (median, 6 cm diameter; range, 4-11 cm diameter) was achieved by transurethral endoscopy in standing sedated horses using an electrohydraulic shockwave fiber introduced through the biopsy channel of an endoscope. The fiber was advanced until it contacted the calculus. Repeated activation of the fiber was used to disrupt the calculus into fragments <1 cm diameter. Visibility within the bladder was maintained by repeated lavage with saline solution. Complete calculus removal was achieved in 20 horses (95%) with mean total surgical time of 168.6 minutes (range, 45-450). In the 20 horses with single calculi, 1-6 sessions were required to completely fragment the calculus. Except for 1 horse, in which perineal urethrotomy was eventually performed for complete fragment removal, fragments calculi were excreted via the urethra. Postoperative complications included hematuria because of severe mucosal erosion (n = 2), dysuria because of a trapped urethral fragment (2), small amount of urinary debris (1). One horse was euthanatized because of bladder rupture. Complete clearance of calculi and urinary debris was confirmed endoscopically 20 (3-45) days after the last session. Telephone follow-up (mean, 18.8 months; range, 7-24 months) revealed that horses had returned to previous activity levels without recurrence of clinical signs. Transendoscopic electrohydraulic lithotripsy appears to be an effective method for fragmentation of low-density calcium carbonate cystic calculi in male horses. Copyright 2012 by The American College of Veterinary Surgeons.

  5. Holmium laser lithotripsy of bladder calculi

    NASA Astrophysics Data System (ADS)

    Beaghler, Marc A.; Poon, Michael W.

    1998-07-01

    Although the overall incidence of bladder calculi has been decreasing, it is still a significant disease affecting adults and children. Prior treatment options have included open cystolitholapaxy, blind lithotripsy, extracorporeal shock wave lithotripsy, and visual lithotripsy with ultrasonic or electrohydraulic probes. The holmium laser has been found to be extremely effective in the treatment of upper tract calculi. This technology has also been applied to the treatment of bladder calculi. We report our experience with the holmium laser in the treatment of bladder calculi. Twenty- five patients over a year and a half had their bladder calculi treated with the Holmium laser. This study was retrospective in nature. Patient demographics, stone burden, and intraoperative and post-operative complications were noted. The mean stone burden was 31 mm with a range of 10 to 60 mm. Preoperative diagnosis was made with either an ultrasound, plain film of the abdomen or intravenous pyelogram. Cystoscopy was then performed to confirm the presence and determine the size of the stone. The patients were then taken to the operating room and given a regional or general anesthetic. A rigid cystoscope was placed into the bladder and the bladder stone was then vaporized using the holmium laser. Remaining fragments were washed out. Adjunctive procedures were performed on 10 patients. These included transurethral resection of the prostate, transurethral incision of the prostate, optic internal urethrotomy, and incision of ureteroceles. No major complications occurred and all patients were rendered stone free. We conclude that the Holmium laser is an effective and safe modality for the treatment of bladder calculi. It was able to vaporize all bladder calculi and provides a single modality of treating other associated genitourinary pathology.

  6. Free electron laser lithotripsy: threshold radiant exposures.

    PubMed

    Chan, K F; Hammer, D X; Choi, B; Teichman, J M; McGuff, H S; Pratisto, H; Jansen, E D; Welch, A J

    2000-03-01

    To determine the threshold radiant exposures (J/cm2) needed for ablation or fragmentation as a function of infrared wavelengths on various urinary calculi and to determine if there is a relation between these thresholds and lithotripsy efficiencies with respect to optical absorption coefficients. Human calculi composed of uric acid, calcium oxalate monohydrate (COM), cystine, or magnesium ammonium phosphate hexahydrate (MAPH) were used. The calculi were irradiated in air with the free electron laser (FEL) at six wavelengths: 2.12, 2.5, 2.94, 3.13, 5, and 6.45 microm. Threshold radiant exposures increased as optical absorption decreased. At the near-infrared wave-lengths with low optical absorption, the thresholds were >1.5 J/cm2. The thresholds decreased below 0.5 J/cm2 for regions of high absorption for all the calculus types. Thresholds within the high-absorption regions were statistically different from those in the low-absorption regions, with P values much less than 0.05. Optical absorption coefficients or threshold radiant exposures can be used to predict lithotripsy efficiencies. For low ablation thresholds, smaller radiant exposures were required to achieve breakdown temperatures or to exceed the dynamic tensile strength of the material. Therefore, more energy is available for fragmentation, resulting in higher lithotripsy efficiencies.

  7. Successful Treatment of Mirizzi’s Syndrome Using SpyGlass Guided Laser Lithotripsy

    PubMed Central

    Issa, Hussain; Bseiso, Bahaa; Almousa, Fadel; Al-Salem, Ahmed H.

    2012-01-01

    The majority of common bile duct stones can be effectively treated by endoscopic sphincterotomy and stone extraction using basket or balloon extractor. Stones more than 2 cm in diameter on the other hand require mechanical, electrohyraulic lithotripsy and sphincterotomy and balloon dilation. Mechanical lithotripsy may not be successful because of the size, consistency and site of the stones. In these cases, laser lithotripsy is the treatment of choice. This however requires direct visualization of the stone which may not be feasible for impacted cystic duct stones. This report describes the successful treatment of difficult cystic duct stones in two patients with Mirizzi’s syndrome type I using per oral Spyglass and intraductal holmium: YAG Laser Lithotripter. PMID:27785198

  8. [Endoscopic contact lithotripsy--modern alternative in the therapy of patients with large stones of the common bile duct].

    PubMed

    Ohorodnyk, P V; Kolomiĭtsev, V I; Kushniruk, O I; Deĭnychenko, A H; Khrystiuk, D I

    2013-09-01

    The peculiarities of therapeutic ERCP and contact lithotripsy in patients with choledocholithiasis were studied. 6516 patients (age from 11 to 94 years old) with choledocholithiasis were examined Endoscopic sphincterotomy/balloon dilation with stone extraction was effective in 5507 (84.5%), in 539 (8.8%)--we achieved bile ducts clearance by using mechanical or electrohydraulic lithotripsy. Additional usage of contact lithotripsy increased the effectiveness of therapeutic ERCP to 93.2%. Contact lithotripsy decreased number of specific for ERCP complication from 7.83% to 1.57% in patients with large (> 25mm) stones. Electrohydraulic lithotripsy was successful in destruction of hard bile stones, when mechanical lithotripsy failed.

  9. Laser lithotripsy with the Ho:YAG laser: fragmentation process revealed by time-resolved imaging

    NASA Astrophysics Data System (ADS)

    Schmidlin, Franz R.; Beghuin, Didier; Delacretaz, Guy P.; Venzi, Giordano; Jichlinski, Patrice; Rink, Klaus; Leisinger, Hans-Juerg; Graber, Peter

    1998-07-01

    Improvements of endoscopic techniques have renewed the interest of urologists in laser lithotripsy in recent years. Laser energy can be easily transmitted through flexible fibers thereby enabling different surgical procedures such as cutting, coagulating and lithotripsy. The Ho:YAG laser offers multiple medical applications in Urology, among them stone fragmentation. However, the present knowledge of its fragmentation mechanism is incomplete. The objective was therefore to analyze the fragmentation process and to discuss the clinical implications related to the underlying fragmentation mechanism. The stone fragmentation process during Ho:YAG laser lithotripsy was observed by time resolved flash video imaging. Possible acoustic transient occurrence was simultaneously monitored with a PVDF-needle hydrophone. Fragmentation was performed on artificial and cystine kidney stones in water. We observed that though the fragmentation process is accompanied with the formation of a cavitation bubble, cavitation has only a minimal effect on stone fragmentation. Fragment ejection is mainly due to direct laser stone heating leading to vaporization of organic stone constituents and interstitial water. The minimal effect of the cavitation bubble is confirmed by acoustic transients measurements, which reveal weak pressure transients. Stone fragmentation with the Holmium laser is the result of vaporization of interstitial (stone) water and organic stone constituents. It is not due to the acoustic effects of a cavitation bubble or plasma formation. The fragmentation process is strongly related with heat production thereby harboring the risk of undesired thermal damage. Therefore, a solid comprehension of the fragmentation process is needed when using the different clinically available laser types of lithotripsy.

  10. Time-resolved imaging of cavitation effects during laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Siano, Salvatore; Pini, Roberto; Salimbeni, Renzo; Vannini, Matteo

    1995-01-01

    We devised a diagnostic technique based on a pump-and-probe scheme that provided time- resolved imaging of photofragmentation effects during laser lithotripsy. The evolution of the cavitation bubble induced on kidney stone samples by underwater irradiation with a XeCl excimer laser is presented and analyzed.

  11. Subcapsular hematoma after ureteroscopy and laser lithotripsy.

    PubMed

    Chiu, Peter Ka-Fung; Chan, Chun-Ki; Ma, Wai-kit; To, Kim-Chung; Cheung, Fu-Keung; Yiu, Ming-kwong

    2013-09-01

    Renal hematoma after ureteroscopic lithotripsy (URSL) using holmium:yttrium-aluminum-garnet (Ho:YAG) laser is a rare complication. We aimed to review our center's experience of post-URSL subcapsular hematoma. From 2007 to 2012, 1114 URSLs using 7.5F semi-rigid ureteroscopes were performed. Patients with post-URSL symptomatic renal hematoma were reviewed. Perioperative information on patients' preoperative morbidity, renal function, stone characteristics, and degree of hydronephrosis were reviewed. Operative information, postoperative presentation of symptoms, changes in blood parameters, CT findings, and subsequent management were documented. Post-URSL subcapsular hematoma was diagnosed in 4 of 1114 (0.36%) patients, who ranged in age from 43 to 63 years. Preoperative imaging showed that all four patients had obstructing proximal ureteral stones ranging in size from 0.7 to 2.1 cm, and three of them had thin renal cortices. Pressure bags were not used, and Double-J ureteral stents were inserted in all cases. All four patients had the triad of loin pain, fever, and significant hemoglobin drop necessitating transfusion. Three patients presented within 2 days of URSL, and one patient presented on day 20. One patient was treated conservatively and recovered with bed rest and antibiotics. Urgent angiography was performed on one patient in view of a significant drop in hemoglobin, but no embolization was needed. One patient underwent ultrasonography-guided drainage of the hematoma, and another had an emergency open clot evacuation because of significant compression on the kidney by the hematoma. Follow-up CT scans confirmed the resolution of the hematoma in all cases. Post-URSL subcapsular hematoma is a rare but potentially serious complication. A high index of suspicion is needed when patients present with significant loin pain and fever after URSL for obstructing proximal ureteral stones with thin renal cortices. The management of post-URSL subcapsular hematomas needs

  12. Laser lithotripsy of salivary stones: Correlation with physical and radiological parameters.

    PubMed

    Schrötzlmair, Florian; Müller, Mona; Pongratz, Thomas; Eder, Matthias; Johnson, Thorsten; Vogeser, Michael; von Holzschuher, Vanessa; Zengel, Pamela; Sroka, Ronald

    2015-04-01

    Sialolithiasis is a common disease of the major salivary glands. Owing to the variety of conservative and minimally invasive techniques, it is now possible to treat most cases of sialolithiasis without removal of the affected salivary gland. One treatment option is the endoscopic removal of the calculi. In cases of larger concretions, intraductal disintegration using laser-induced shock waves can be appropriate to allow endoscopic removal. In the present study, we investigated whether physical and radiological parameters of salivary stones can effectively predict the applicability of laser lithotripsy. Furthermore, we determined to what extent the applied laser energy resulted in tissue damage. In addition to basic parameters like size and density, we analysed 47 salivary stones using fluorescence spectroscopy, infrared spectroscopy, Raman spectroscopy, and dual-energy computed tomography. Subsequent fragmentation of all stones was performed with a Ho:YAG laser in a near-contact manner. Fragmentation rates were calculated and correlated with the previously measured physical and radiological parameters. Finally, to test for tissue damage, we performed HE-histology of salivary duct mucosa treated with the same laser energy used for stone fragmentation. Blue light excitation induced either green or red fluorescence emission. Dual-energy CT resulted in evidence of calcium-containing material. Infrared spectroscopy and Raman spectroscopy, both identified carbonate apatite as the main component of salivary stones. Disintegration into pieces smaller than 2 mm was possible in all cases. Fragmentation rates depended on the energy per pulse applied but not on any of the analysed physical and radiological parameters. In contrast to lithotripsy with 500 mJ per pulse, which was associated with no tissue damage, lithotripsy with 1,000 mJ per pulse resulted in damage of salivary duct mucosa. This suggests that the optimal laser energy for stone fragmentation is between 500

  13. Laser and acoustic lens for lithotripsy

    DOEpatents

    Visuri, Steven R.; Makarewicz, Anthony J.; London, Richard A.; Benett, William J.; Krulevitch, Peter; Da Silva, Luiz B.

    2002-01-01

    An acoustic focusing device whose acoustic waves are generated by laser radiation through an optical fiber. The acoustic energy is capable of efficient destruction of renal and biliary calculi and deliverable to the site of the calculi via an endoscopic procedure. The device includes a transducer tip attached to the distal end of an optical fiber through which laser energy is directed. The transducer tip encapsulates an exogenous absorbing dye. Under proper irradiation conditions (high absorbed energy density, short pulse duration) a stress wave is produced via thermoelastic expansion of the absorber for the destruction of the calculi. The transducer tip can be configured into an acoustic lens such that the transmitted acoustic wave is shaped or focused. Also, compressive stress waves can be reflected off a high density/low density interface to invert the compressive wave into a tensile stress wave, and tensile stresses may be more effective in some instances in disrupting material as most materials are weaker in tension than compression. Estimations indicate that stress amplitudes provided by this device can be magnified more than 100 times, greatly improving the efficiency of optical energy for targeted material destruction.

  14. Holmium:YAG laser lithotripsy for the management of urolithiasis in small ruminants and pot-bellied pigs

    NASA Astrophysics Data System (ADS)

    Halland, Spring K.; House, John K.; George, Lisle

    2001-05-01

    Obstructive urolithiasis is a common problem in small ruminants and pot-bellied pigs. The most common site of urinary tract obstruction in these species is the urethra. Surgical procedures developed to relieve obstructions, in our experience have been effective in approximately 75% of cases. Urethral stricture is a common complication if the mucosa of the urethra is disrupted. The objective of this project was to evaluate endoscopy guided laser lithotripsy as a therapeutic modality to relieve urethral obstructions in small ruminants and pot-bellied pigs. The study population consisted of patients presented to the Veterinary Medical Teaching Hospital at the University of California Davis with obstructive urolithiasis. Lithotripsy was performed using a Holmium:YAG laser via a 200-micron low water quartz fiber passed through a flexible mini-endoscope. Two types of urinary calculi were managed with this technique, calcium carbonate and calcium hydroxyphosphate. Laser lithotripsy was effective at relieving obstructions caused by both types of calculi when conventional methods had failed. Laser lithotripsy performed via urethral endoscopy is a safe and effective therapeutic modality for management of obstructive urolithiasis in small ruminants and pot-bellied pigs and reduces the risk of post procedural urethral stricture.

  15. Laparoscopic Transcystic Treatment Biliary Calculi by Laser Lithotripsy

    PubMed Central

    Jin, Lan; Zhang, Zhongtao

    2016-01-01

    Background and Objectives: Laparoscopic transcystic common bile duct exploration (LTCBDE) is a complex procedure requiring expertise in laparoscopic and choledochoscopic skills. The purpose of this study was to investigate the safety and feasibility of treating biliary calculi through laparoscopic transcystic exploration of the CBD via an ultrathin choledochoscope combined with dual-frequency laser lithotripsy. Methods: From August 2011 through September 2014, 89 patients at our hospital were treated for cholecystolithiasis with biliary calculi. Patients underwent laparoscopic cholecystectomy and exploration of the CBD via the cystic duct and the choledochoscope instrument channel. A dual-band, dual-pulse laser lithotripsy system was used to destroy the calculi. Two intermittent laser emissions (intensity, 0.12 J; pulse width 1.2 μs; and pulse frequency, 10 Hz) were applied during each contact with the calculi. The stones were washed out by water injection or removed by a stone-retrieval basket. Results: Biliary calculi were removed in 1 treatment in all 89 patients. No biliary tract injury or bile leakage was observed. Follow-up examination with type-B ultrasonography or magnetic resonance cholangiopancreatography 3 months after surgery revealed no instances of retained-calculi–related biliary tract stenosis. Conclusion: The combined use of laparoscopic transcystic CBD exploration by ultrathin choledochoscopy and dual-frequency laser lithotripsy offers an accurate, convenient, safe, effective method of treating biliary calculi. PMID:27904308

  16. Laser lithotripsy for ureteric calculi: results in 250 patients.

    PubMed Central

    Kelly, J. D.; Keane, P. F.; Johnston, S. R.; Kernohan, R. M.

    1995-01-01

    Two hundred and fifty patients with 290 stones presenting to the Department of Urology were treated with the Candela MDL 2000 Laser Lithotripter. Overall stone clearance rate was 95%. The more proximal the calculus the lower the success rate. Ninety eight percent of stones in the lower ureter, 95% of mid ureteric and 91% of upper ureteric stones were cleared. The major complication was perforation which occurred in 6% of cases. This procedure is a safe and effective treatment for ureteric calculi and is associated with a low complication rate and a high clearance rate. Laser lithotripsy is the optimum ureteroscopic method of treating ureteric calculi and is complimentary to extra corporeal shock wave lithotripsy. PMID:8533176

  17. Influence of Saline on Temperature Profile of Laser Lithotripsy Activation

    PubMed Central

    Silva, Igor N.; Donalisio da Silva, Rodrigo; Gustafson, Diedra; Sehrt, David; Kim, Fernando J.

    2015-01-01

    Abstract Purpose: We established an ex vivo model to evaluate the temperature profile of the ureter during laser lithotripsy, the influence of irrigation on temperature, and thermal spread during lithotripsy with the holmium:yttrium-aluminum-garnet (Ho:YAG) laser. Materials and Methods: Two ex vivo models of Ovis aries urinary tract and human calcium oxalate calculi were used. The Open Ureteral Model was opened longitudinally to measure the thermal profile of the urothelium. On the Clinical Model, anterograde ureteroscopy was performed in an intact urinary system. Temperatures were measured on the external portion of the ureter and the urothelium during lithotripsy and intentional perforation. The lithotripsy group (n=20) was divided into irrigated (n=10) and nonirrigated (n=10), which were compared for thermal spread length and values during laser activation. The intentional perforation group (n=10) was evaluated under saline flow. The Ho:YAG laser with a 365 μm laser fiber and power at 10W was used (1J/Pulse at 10 Hz). Infrared Fluke Ti55 Thermal Imager was used for evaluation. Maximum temperature values were recorded and compared. Results: On the Clinical Model, the external ureteral wall obtained a temperature of 37.4°C±2.5° and 49.5°C±2.3° (P=0.003) and in the Open Ureteral Model, 49.7°C and 112.4°C with and without irrigation, respectively (P<0.05). The thermal spread along the external ureter wall was not statically significant with or without irrigation (P=0.065). During intentional perforation, differences in temperatures were found between groups (opened with and without irrigation): 81.8°±8.8° and 145.0°±15.0°, respectively (P<0.005). Conclusion: There is an increase in the external ureteral temperature during laser activation, but ureteral thermal values decreased when saline flow was applied. Ureter thermal spread showed no difference between irrigated and nonirrigated subgroups. This is the first laser lithotripsy thermography study

  18. Influence of saline on temperature profile of laser lithotripsy activation.

    PubMed

    Molina, Wilson R; Silva, Igor N; Donalisio da Silva, Rodrigo; Gustafson, Diedra; Sehrt, David; Kim, Fernando J

    2015-02-01

    We established an ex vivo model to evaluate the temperature profile of the ureter during laser lithotripsy, the influence of irrigation on temperature, and thermal spread during lithotripsy with the holmium:yttrium-aluminum-garnet (Ho:YAG) laser. Two ex vivo models of Ovis aries urinary tract and human calcium oxalate calculi were used. The Open Ureteral Model was opened longitudinally to measure the thermal profile of the urothelium. On the Clinical Model, anterograde ureteroscopy was performed in an intact urinary system. Temperatures were measured on the external portion of the ureter and the urothelium during lithotripsy and intentional perforation. The lithotripsy group (n=20) was divided into irrigated (n=10) and nonirrigated (n=10), which were compared for thermal spread length and values during laser activation. The intentional perforation group (n=10) was evaluated under saline flow. The Ho:YAG laser with a 365 μm laser fiber and power at 10W was used (1J/Pulse at 10 Hz). Infrared Fluke Ti55 Thermal Imager was used for evaluation. Maximum temperature values were recorded and compared. On the Clinical Model, the external ureteral wall obtained a temperature of 37.4°C±2.5° and 49.5°C±2.3° (P=0.003) and in the Open Ureteral Model, 49.7°C and 112.4°C with and without irrigation, respectively (P<0.05). The thermal spread along the external ureter wall was not statically significant with or without irrigation (P=0.065). During intentional perforation, differences in temperatures were found between groups (opened with and without irrigation): 81.8°±8.8° and 145.0°±15.0°, respectively (P<0.005). There is an increase in the external ureteral temperature during laser activation, but ureteral thermal values decreased when saline flow was applied. Ureter thermal spread showed no difference between irrigated and nonirrigated subgroups. This is the first laser lithotripsy thermography study establishing the framework to evaluate the temperature

  19. Intracorporeal lithotripsy with the holmium:YAG laser

    NASA Astrophysics Data System (ADS)

    Denstedt, John D.; Razvi, Hassan A.; Chun, Samuel S.; Sales, Jack L.

    1995-05-01

    A variety of devices are currently available for intracorporeal stone fragmentation. Recently a new wavelength of laser, the Holmium:YAG, has demonstrated a variety of potential urologic applications including ablation of soft tissue lesions as well as stone fragmentation. This laser has a wavelength of 2100 nm and operates in a pulsed mode. Energy is delivered through a 400 um quartz end-firing fiber. In this presentation we review our clinical experience with the Holmium:YAG laser for the treatment of renal and ureteral calculi. Over a 23 month period, 63 patients underwent 67 procedures. Seven procedures consisted of percutaneous nephrolithotripsy for large or staghorn renal calculi. Sixty procedures were performed for ureteral stones. Procedures for proximal ureteral stones (6) employed a retrograde approach using flexible ureteroscopes (8.5 or 9.8). Stones in the mid ureter (12) and distal ureter (42) were approached transurethrally using a 6.9 rigid ureteroscope. Complete stone fragmentation without the need for additional procedures was achieved in 82% of cases. Treatment failures included 1 stone migration into the renal pelvis during laser activation, 6 patients who had incomplete fragmentation and 3 patients in which laser malfunction precluded complete fragmentation. Stone analysis available in 23 patients revealed calcium oxalate monohydrate (15), calcium oxalate dihydrate (2), cystine (2), uric acid (3) and calcium phosphate (1). A single complication of ureteral perforation occurred when the laser was fired without direct visual guidance. Radiographic follow-up at an average of 16 weeks is available in 22 patients and has identified 2 patients with ureteral strictures that are not believed to be related to laser lithotripsy. In summary, we have found the Holmium:YAG laser to be a reliable and versatile device for intracorporeal lithotripsy. Its safety and efficacy make it a suitable alternative for performing intracorporeal lithotripsy of urinary

  20. Laser-induced shock-wave lithotripsy of canine urocystoliths and nephroliths

    NASA Astrophysics Data System (ADS)

    Woods, J. P.; Bartels, Kenneth E.; Stair, Ernest L.; Schafer, Steven A.; Nordquist, Robert E.

    1997-05-01

    Urolithiasis is a common disease affecting dogs which can sometimes be treated with dietary and medical protocols. In many cases, however, medical management cannot be employed because the dietary restrictions are contraindicated, effective medical dissolution protocols for the calculi (uroliths) do not exist, or obstruction by the calculi may result in deterioration of renal function during the time required for medical dissolution. At present, the management of medically untreatable calculi has been surgical removal which may result in temporary but dramatic decrease in renal function, irreversible loss of damaged nephrons, and significant risk, particularly for bilateral or recurrent nephroliths. An innovative technique for the removal of these uroliths would involve laser lithotripsy which transforms light energy into acoustical energy generating a shock wave sufficient to fragment stones (photoacoustic ablation). The laser is transmitted via quartz fibers which are small and flexible and can be used under direct vision through endoscopes resulting in effective fragmentation with little surrounding tissue damage. Lasers are becoming increasingly more utilized in veterinary medicine, in contrast to the limited availability of other non-invasive methods of treatment of nephroliths (i.e. extracorporeal shock-wave lithotripsy).

  1. Efficacy of retrograde ureteropyeloscopic holmium laser lithotripsy for intrarenal calculi >2 cm.

    PubMed

    Bader, M J; Gratzke, C; Walther, S; Weidlich, P; Staehler, M; Seitz, M; Sroka, R; Reich, O; Stief, C G; Schlenker, B

    2010-10-01

    The objectives of this study are to assess the efficacy and safety of retrograde ureteroscopic holmium laser lithotripsy for intrarenal calculi greater than 2 cm in diameter. A total of 24 patients with a stone burden >2 cm were treated with retrograde ureteroscopic laser lithotripsy. Primary study endpoints were number of treatments until the patient was stone free and perioperative complications with a follow-up of at least 3 months after intervention. In 24 patients (11 women and 13 men, 20-78 years of age), a total of 40 intrarenal calculi were treated with retrograde endoscopic procedures. At the time of the initial procedure, calculi had an average total linear diameter of 29.75 ± 1.57 mm and an average stone volume of 739.52 ± 82.12 mm(3). The mean number of procedures per patient was 1.7 ± 0.8 (range 1-3 procedures). The overall stone-free rate was 92%. After 1, 2 and 3 procedures 54, 79 and 92% of patients were stone free, respectively. There were no major complications. Minor postoperative complications included pyelonephritis in three cases (7.5%), of whom all responded immediately to parenteral antibiotics. In one patient the development of steinstrasse in the distal ureter required ureteroscopic fragment disruption and basketing. Ureteroscopy with holmium laser lithotripsy represents an efficient treatment option and allows the treatment of large intrarenal calculi of all compositions and throughout the whole collecting system even for patients with a stone burden of more than 2 cm size.

  2. Endoscopic Salivary Stone Fragmentation with Pneumatic Lithotripsy in a Simulation Model.

    PubMed

    Hoffman, Henry T; Walvekar, Rohan R; Tracy, Chad R; Kolenda, Jack; Pagedar, Nitin

    2016-03-01

    To evaluate the endoscopic fragmentation and removal of human salivary stones by employing intracorporeal pneumatic lithotripsy in a clinical simulation model of the submandibular gland. Simulation model evaluating endoscopic management of human salivary stones. Laboratory. A flexible nitinol contact probe adapted to a CO2-driven handheld salivary pneumatic lithotripter was deployed through a sialendoscope to disrupt parotid (n = 1) and submandibular (n = 8) stones embedded in separate 3-dimensionally printed plastic models of the mouth and submandibular glands. Simulation included endoscopic removal of small stone fragments by standard basket retrieval supplement by irrigation and suction through a salivary duct introducer system. Correlations were made between stone volume and density with the duration of the procedures and number of pneumatic pulses required to disrupt and remove stone fragments. Among the 8 stones fragmented sufficiently to permit either full endoscopic removal (n = 7) or removal of the central portion leaving an adherent rind to the duct (n = 1), the average procedure time (32 minutes) and the average number of pneumatic pulses (98) correlated with stone density (range, 0.4-1.5 g/mL) and stone volume (range, 0.05-0.4 mL). One stone was sufficiently resistant to fragmentation as to prevent successful removal. Modification to the evolving technology of intracorporeal pneumatic management of nephrolithiasis was successfully applied in an ex vivo model to simulate management of sialolithiasis. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  3. Thulium fiber laser lithotripsy in an in vitro ureter model.

    PubMed

    Hardy, Luke A; Wilson, Christopher R; Irby, Pierce B; Fried, Nathaniel M

    2014-12-01

    Using a validated in vitro ureter model for laser lithotripsy, the performance of an experimental thulium fiber laser (TFL) was studied and compared to the clinical gold standard holmium:YAG laser. The holmium laser (λ = 2120 nm) was operated with standard parameters of 600 mJ, 350 μs, 6 Hz, and 270-μm-core optical fiber. The TFL (λ=1908 nm) was operated with 35 mJ, 500 μs, 150 to 500 Hz, and a 100-μm-core fiber. Urinary stones (60% calcium oxalate monohydrate/40% calcium phosphate) of uniform mass and diameter (4 to 5 mm) were laser ablated with fibers through a flexible video-ureteroscope under saline irrigation with flow rates of 22.7 and 13.7 ml/ min for the TFL and holmium laser, respectively. The temperature 3 mm from the tube's center and 1 mm above the mesh sieve was measured by a thermocouple and recorded throughout each experiment for both lasers. Total laser and operation times were recorded once all stone fragments passed through a 1.5-mm sieve. The holmium laser time measured 167±41 s (n=12). TFL times measured 111±49, 39±11, and 23±4 s, for pulse rates of 150, 300, and 500 Hz, respectively (n=12 each). Mean peak saline irrigation temperatures reached 24±1°C for holmium, and 33±3°C, 33±7°C, and 39±6°C, for TFL at pulse rates of 150, 300, and 500 Hz, respectively. To avoid thermal buildup and provide a sufficient safety margin, TFL lithotripsy should be performed with pulse rates below 500 Hz and/or increased saline irrigation rates. The TFL rapidly fragmented kidney stones due in part to its high pulse rate, high power density, high average power, and observation of reduced stone retropulsion and may provide a clinical alternative to the conventional holmium laser for lithotripsy.

  4. Thulium fiber laser lithotripsy in an in vitro ureter model

    NASA Astrophysics Data System (ADS)

    Hardy, Luke A.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

    2014-12-01

    Using a validated in vitro ureter model for laser lithotripsy, the performance of an experimental thulium fiber laser (TFL) was studied and compared to the clinical gold standard holmium:YAG laser. The holmium laser (λ=2120 nm) was operated with standard parameters of 600 mJ, 350 μs, 6 Hz, and 270-μm-core optical fiber. The TFL (λ=1908 nm) was operated with 35 mJ, 500 μs, 150 to 500 Hz, and a 100-μm-core fiber. Urinary stones (60% calcium oxalate monohydrate/40% calcium phosphate) of uniform mass and diameter (4 to 5 mm) were laser ablated with fibers through a flexible video-ureteroscope under saline irrigation with flow rates of 22.7 and 13.7 ml/min for the TFL and holmium laser, respectively. The temperature 3 mm from the tube's center and 1 mm above the mesh sieve was measured by a thermocouple and recorded throughout each experiment for both lasers. Total laser and operation times were recorded once all stone fragments passed through a 1.5-mm sieve. The holmium laser time measured 167±41 s (n=12). TFL times measured 111±49, 39±11, and 23±4 s, for pulse rates of 150, 300, and 500 Hz, respectively (n=12 each). Mean peak saline irrigation temperatures reached 24±1°C for holmium, and 33±3°C, 33±7°C, and 39±6°C, for TFL at pulse rates of 150, 300, and 500 Hz, respectively. To avoid thermal buildup and provide a sufficient safety margin, TFL lithotripsy should be performed with pulse rates below 500 Hz and/or increased saline irrigation rates. The TFL rapidly fragmented kidney stones due in part to its high pulse rate, high power density, high average power, and observation of reduced stone retropulsion and may provide a clinical alternative to the conventional holmium laser for lithotripsy.

  5. Thulium fiber laser lithotripsy using a muzzle brake fiber tip

    NASA Astrophysics Data System (ADS)

    Hutchens, Thomas C.; Gonzalez, David A.; Irby, Pierce B.; Fried, Nathaniel M.

    2017-02-01

    The Thulium fiber laser (TFL) is being explored as an alternative to Holmium:YAG laser for lithotripsy. TFL beam profile allows coupling of higher power into smaller fibers than multimode Holmium laser beam, without proximal fiber tip degradation. A smaller fiber provides more space in ureteroscope working channel for increased saline irrigation and allows maximum ureteroscope flexion. However, distal fiber tip burnback increases as fiber diameter decreases. Previous studies utilizing hollow steel sheaths around recessed distal fiber tips reduced fiber burnback, but increased retropulsion. In this study, a "fiber muzzle brake" was tested for reducing fiber burnback and stone retropulsion. TFL lithotripsy studies were performed at 1908 nm, 35 mJ, 500 μs, and 300 Hz using a 100-μm-core fiber. The optimal stainless steel muzzle brake tip tested consisted of a 1-cm-long, 560-μm-OD, 360-μm-ID tube with 275-μm thru hole located 250-μm from the distal end. The fiber tip was recessed a distance of 500 μm. Stone phantom retropulsion, fiber tip burnback, and calcium oxalate stone ablation studies were performed, ex vivo. Small stones with a mass of 40 +/- 4 mg and 4-mm-diameter were ablated over a 1.5-mm sieve in 25 +/- 4 s (n=10), without distal fiber tip burnback. Reduction in stone phantom retropulsion distance by 50% and 85% was observed when using muzzle brake tips versus 100-μm-core bare fibers and hollow steel tip fibers. The muzzle brake fiber tip provided efficient stone ablation, reduced stone retropulsion, and minimal fiber degradation during TFL lithotripsy.

  6. Miniature ureteroscope tip designs for use in thulium fiber laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Kennedy, Joshua D.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

    2017-02-01

    A miniature ureteroscope has the potential to eliminate need for full anesthesia and dilation, increase comfort and safety of laser lithotripsy via ureteroscopy, and reduce hospital costs via an office based procedure. A prototype, 4.5 Fr (1.5-mm-OD), five channel ureteroscope tip was developed, housing a 200-μm-ID central channel for insertion of small, 100-μm-core fibers and four surrounding channels, each with 510-μm-ID for instrumentation, irrigation, imaging, and illumination, respectively. Common urological instruments (including fibers, guidewires, and stone baskets) were inserted through tip's working channels to demonstrate feasibility. Low irrigation rates were measured, revealing a need for manual pump-assisted irrigation. Imaging was conducted using 3k, 6k, and 10k pixel miniature flexible endoscopes with 0.4, 0.6, and 0.9 mm outer diameters, respectively. The 3k pixel endoscope with integrated illumination was inserted through the prototype unimpeded, and successfully demonstrated ability to differentiate between hard tissues (e.g. kidney stones) and soft tissues (e.g. ureter wall), for visibility and safety during potential clinical application. Based on both image quality and instrument diameter, the 6k pixel endoscope provided an optimal solution for miniature ureteroscopy.

  7. Laser lithotripsy of a urethral calculus via ischial urethrotomy in a steer.

    PubMed

    Streeter, R N; Washburn, K E; Higbee, R G; Bartels, K E

    2001-09-01

    A steer examined because of obstructive urolithiasis and urethral rupture underwent laser lithotripsy, using a chromium-thulium-holmium:yttrium-aluminum-garnet (Ho:YAG) laser inserted through an ischial urethrotomy. Procedures were performed with caudal epidural anesthesia. Six months after surgery, the urethra was patent with no clinical evidence of urethral stricture or fistula. Ischial urethrotomy provided rapid access to the bladder for catheterization and to the obstructive urolith for lithotripsy. Laser lithotripsy was a rapid and effective means of urolith removal in this steer.

  8. Cavitation bubble dynamics during thulium fiber laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Hardy, Luke A.; Kennedy, Joshua D.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

    2016-02-01

    The Thulium fiber laser (TFL) is being explored for lithotripsy. TFL parameters differ from standard Holmium:YAG laser in several ways, including smaller fiber delivery, more strongly absorbed wavelength, low pulse energy/high pulse rate operation, and more uniform temporal pulse structure. High speed imaging of cavitation bubbles was performed at 105,000 fps and 10 μm spatial resolution to determine influence of these laser parameters on bubble formation. TFL was operated at 1908 nm with pulse energies of 5-75 mJ, and pulse durations of 200-1000 μs, delivered through 100-μm-core fiber. Cavitation bubble dynamics using Holmium laser at 2100 nm with pulse energies of 200-1000 mJ and pulse duration of 350 μs was studied, for comparison. A single, 500 μs TFL pulse produced a bubble stream extending 1090 +/- 110 μm from fiber tip, and maximum bubble diameters averaged 590 +/- 20 μm (n=4). These observations are consistent with previous studies which reported TFL ablation stallout at working distances < 1.0 mm. TFL bubble dimensions were five times smaller than for Holmium laser due to lower pulse energy, higher water absorption coefficient, and smaller fiber diameter used.

  9. Safety and efficacy of holmium:YAG laser lithotripsy in patients with bleeding diatheses

    NASA Astrophysics Data System (ADS)

    Watterson, James D.; Girvan, Andrew R.; Cook, Anthony J.; Beiko, Darren T.; Nott, Linda; Auge, Brian K.; Preminger, Glenn M.; Denstedt, John D.

    2003-06-01

    Purpose: To assess the safety and efficacy of ureteroscopy and holmium:YAG (yttrium-aluminum-garnet) laser lithotripsy in the treatment of upper urinary tract calculi in patients with known and uncorrected bleeding diatheses. Materials and Methods: A retrospective chart review from 2 tertiary stone centers was performed to identify patients with known bleeding diatheses who were treated with holmium:YAG laser lithotripsy for upper urinary tract calculi. Twenty-five patients with 29 upper urinary tract calculi were treated with ureteroscopic holmium laser lithotripsy. Bleeding diatheses identified were coumadin administration for various conditions (17), liver dysfunction (3), thrombocytopenia (4), and von Willebrand's disease (1). Mean international normalized ratio (INR), platelet count and bleeding time were 2.3, 50 x 109/L, and > 16 minutes, for patients receiving coumadin or with liver dysfunction, thrombocytopenia, or von Willebrand's disease, respectively. Results: Overall, the stone-free rate was 96% (27/28) and 29 of 30 procedures were completed successfully without significant complication. One patient who was treated concomitantly with electrohydraulic lithotripsy (EHL) had a significant retroperitoneal hemorrhage that required blood transfusion. Conclusions: Treatment of upper tract urinary calculi in patients with uncorrected bleeding diatheses can be safely performed using contemporary small caliber ureteroscopes and holmium laser as the sole modality of lithotripsy. Ureteroscopic holmium laser lithotripsy without preoperative correction of hemostatic parameters limits the risk of thromboembolic complications and costs associated with an extended hospital stay. Avoidance of the use of EHL is crucial in reducing bleeding complications in this cohort of patients.

  10. Experience with endoscopic holmium laser in the pediatric population

    NASA Astrophysics Data System (ADS)

    Merguerian, Paul A.; Reddy, Pramod P.; Barrieras, Diego; Bagli, Darius J.; McLorie, Gordon A.; Khoury, Antoine E.

    1999-06-01

    Introduction: Due to the unavailability of suitable endoscopic instruments, pediatric patients have not benefited fully from the technological advances in the endoscopic management of the upper urinary tract. This limitation may be overcome with the Holmuim:Yttrium-Aluminum-Garnet(Ho:YAG) laser delivered via small instruments. To date, there is no published report on the use of this modality in children. Purpose: We evaluated the indications, efficacy, and complications of endourological Ho:YAG laser surgery in the treatment of pediatric urolithiasis, posterior urethral valves, ureterocele and ureteropelvic junction obstruction. Methods: The patient population included 10 children with renal, ureteral and bladder calculi, 2 children with posterior urethral valves, 2 children with obstructing ureteroceles, 2 children with ureteropelvic junction obstruction and 1 child with a urethral stricture. Access to the lesions was either antegrade via a percutaneous nephrostomy tract or retrograde via the urethra. A solid state Ho:YAG laser with maximum output of 30 watts (New Star lasers, Auburn, CA) was utilized as the energy source. Results: A total of 10 patients underwent laser lithotripsy. The means age of the patients was 9 yrs (5-13 yrs). The average surface area of the calculi as 425.2 mm2 (92-1645 mm2). 8 of the patients required one procedure to render them stone free, one patient had a staghorn calculus filling every calyx of a solitary kidney requiring multiple treatments and one other patient with a staghorn calculus required 2 treatments. There were no complications related to the laser lithotripsy. Two newborn underwent successful ablation of po sterious urethral valves. Two infants underwent incision of obstructing ureteroceles with decompression of the ureterocele on postoperative ultrasound. Two children underwent endypyelotomy for ureteropelvic junction obstruction. One was successful an done required an open procedure to correct the obstruction. One child

  11. [Laser in gastroenterologic endoscopic therapy].

    PubMed

    Naveau, S; Chaput, J C

    1991-01-21

    Endoscopic gastrointestinal laser therapy was originally inspired by the haemostatic properties of the laser beam and was subsequently used to destroy tumours. In endoscopic gastroenterology, the most commonly used type of laser is the neodyme+-doped yttrium aluminium garnet (Nd:YAG) laser. Endoscopic Nd:YAG laser therapy of obstructive cancers of the oesophagus and cardia rapidly reduces dysphagia in 70 to 100% of the patients. In the treatment of colorectal cancers, the intestinal transit returns to normal in 57 to 83% of the cases, and rectal haemorrhages are controlled in 38 to 92% of the cases. However, sustained results can only be obtained by a maintenance treatment with at least one application every 4 weeks. The Nd:YAG laser makes it possible to destroy villose tumours in patients who cannot, or will not, be operated upon; the number of applications depends on the size of the tumour. Finally, the Nd:YAG laser seems to be able to control bleeding due to gastrointestinal angiodysplasia and to stabilize the course of Rendu-Osler-Weber disease.

  12. Endoscopic treatment of Bouverets syndrome in an extremely elderly patient with Holmium: YAG laser.

    PubMed

    Chang, Kao-Chi; Chen, Wei-Ming; Wei, Kuo-Liang

    2016-01-01

    Bouveret's syndrome is a rare presentation of duodenal obstruction or gastric outlet obstruction caused by a large gallstone migrating through a cholecystoduodenal or choledochoduodenal fistula. Most patients are elderly and often have underlying comorbidities, complicating surgery. Endoscopic therapy should be used as first-line treatment for these patients who are not good surgical candidates. We report a case of a 98-year-old Chinese female who presented with vomiting for three days. Esophagogastroduodenoscopy and computed tomography confirmed the diagnosis of Bouveret's syndrome. The patient successfully underwent endoscopic lithotripsy with the Holmium: Yttrium- Aluminum-Garnet (Ho: YAG) laser. Ho: YAG laser lithotripsy has been used to treat Bouveret's syndrome in four case reports. It can be recommended in patients with Bouveret's syndrome who are poor candidates for surgery.

  13. Holmium laser intrarenal lithotripsy in pyelocaliceal lithiasis treatment: to dust or to extractable fragments?

    PubMed

    Mulţescu, R; Geavlete, B; Georgescu, D; Geavlete, P; Chiuţu, L

    2014-01-01

    Pyelocaliceal calculi flexible ureteroscopic approach raises problems related to operative time, associated morbidity and costs, especially by potential endoscope damage. 5 series, each of 20 patients with single pyelocaliceal lithiasis, were analyzed: Group I with calculi 1 cm fragmented to dust, Group II with calculi 1 cm with lithotripsy in fragments, Group III with calculi of 1-2 cm fragmented to dust, Group IV with calculi of 1-2 cm with lithotripsy in fragments, Group V with calculi of 1-2 cm fragmented to dust until they reached 1 cm, and lithotripsy in fragments afterwards. In all cases Ho:YAG lithotripsy was used. Ureteral access sheath was used in 70% of the cases. Mean operating time was 39 min in group I, 21 min in Group II, 112 min in group III, 72 min in group IV and 51 min in group V. Minor complications occurred in 7 cases,while a single major complication occurred in group IV. The optimal lithotripsy method for calculi 1cm seems to be in extractable fragments. Larger calculi should be fragmented to dust until they reach 1 cm and then the lithotripsy should be continued into extractable fragments. Ho: YAG - Holmium: Yttrium Aluminium Garnet, Hz - Hertz, mJ - milli joule. Celsius.

  14. Video. Laparoscopic common bile duct exploration and holmium laser lithotripsy: a novel approach to the management of common bile duct stones.

    PubMed

    Varban, Oliver; Assimos, Dean; Passman, Corey; Westcott, Carl

    2010-07-01

    Endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic common bile duct exploration (LCBDE) have proved to be safe and effective ways of managing common bile duct (CBD) stones. Clearance of large or impacted CBD stones by routine endoscopic maneuvers can be challenging, often requiring more invasive techniques such as open CBD exploration, which increases morbidity. This report presents a novel approach to managing impacted CBD stones using laparoscopic transcystic common bile duct exploration and holmium laser lithotripsy with favorable outcomes. This retrospective review analyzes five patients who underwent laparoscopic cholecystectomy with intraoperative management of impacted CBD stones via LCBDE and holmium laser lithotripsy. The technique is described, and outcomes are measured. Data via chart review and use of intraoperative video were obtained with institutional review board approval. Stone clearance from the CBD was achieved for all the patients. The median age of the patients was 39 years. The diameters of the CBDs ranged from 10 to 20 mm, and the median number of stones was one. No mortality was associated with this procedure, and the median hospital stay was 2 days. Laparoscopic CBD exploration via a transcystic approach together with holmium laser lithotripsy is a safe and effective way to clear large solitary or impacted CBD stones. This technique also avoids choledochotomy and may be used in concert with other methods such as ERCP, percutaneous cholangioscopy, and open exploration.

  15. Endoscopic laser therapy in gastroenterology.

    PubMed

    Pritikin, J; Weinman, D; Harmatz, A; Young, H

    1992-07-01

    Endoscopic laser therapy has become an important and widely used tool in gastroenterology. It has become important for outpatient palliative therapy for ablating obstructing gastrointestinal neoplasms. This method has often circumvented the need for major palliative surgical resections. Caution must be applied to laser therapy for potentially curable malignant neoplasms because, with vaporization of the target tissue, no tissue specimen is available to assure that local or invasive residual carcinoma is excluded. Therefore, in good surgical candidates, surgical resection of potentially curable cancers is always recommended. In the future, however, the combination of refined endoscopic ultrasonography and laser fluorescence techniques may lead to earlier detection, more precise localization, and even curative ablation of gastrointestinal malignancy.

  16. Endoscopic laser therapy in gastroenterology.

    PubMed Central

    Pritikin, J; Weinman, D; Harmatz, A; Young, H

    1992-01-01

    Endoscopic laser therapy has become an important and widely used tool in gastroenterology. It has become important for outpatient palliative therapy for ablating obstructing gastrointestinal neoplasms. This method has often circumvented the need for major palliative surgical resections. Caution must be applied to laser therapy for potentially curable malignant neoplasms because, with vaporization of the target tissue, no tissue specimen is available to assure that local or invasive residual carcinoma is excluded. Therefore, in good surgical candidates, surgical resection of potentially curable cancers is always recommended. In the future, however, the combination of refined endoscopic ultrasonography and laser fluorescence techniques may lead to earlier detection, more precise localization, and even curative ablation of gastrointestinal malignancy. Images PMID:1413743

  17. Management of upper ureteral stones exceeding 15 mm in diameter: Shock wave lithotripsy versus semirigid ureteroscopy with holmium:yttrium–aluminum–garnet laser lithotripsy

    PubMed Central

    Aboutaleb, Hamdy; Omar, Mohamed; Salem, Shady; Elshazly, Mohamed

    2016-01-01

    Objectives: We conducted a retrospective study to evaluate the efficacy and outcome of shock wave lithotripsy versus semirigid ureteroscopy in the management of the proximal ureteral stones of diameter exceeding 15 mm. Methods: During the 2009−2014 study period, 147 patients presenting with the proximal ureteral stones exceeding 15 mm in diameter were treated. Both shock wave lithotripsy and ureteroscopy with laser lithotripsy were offered for our patients. A 6/8.9 Fr semirigid ureteroscope was used in conjunction with a holmium:yttrium–aluminum–garnet laser. The stone-free rate was assessed at 2 weeks and 3 months post-treatment. All patients were evaluated for stone-free status, operation time, hospital stay, perioperative complications, and auxiliary procedures. Results: Of the 147 patients who took part in this study, 66 (45%) had undergone shock wave lithotripsy and 81 (55%) underwent ureteroscopy. At the 3-month follow-up, the overall stone-free rate in the shock wave lithotripsy group was 39/66 (59%) compared to 70/81 (86.4%) in the ureteroscopic laser lithotripsy group. Ureteroscopic laser lithotripsy achieved a highly significant stone-free rate (p = 0.0002), and the mean operative time, auxiliary procedures, and postoperative complication rates were comparable between the two groups. Conclusion: In terms of the management of proximal ureteral stones exceeding 15 mm in diameter, ureteroscopy achieved a greater stone-free rate and is considered the first-line of management. Shock wave lithotripsy achieved lower stone-free rate, and it could be used in selected cases. PMID:28348743

  18. Efficacy and safety of novel digital single-operator peroral cholangioscopy-guided laser lithotripsy for complicated biliary stones

    PubMed Central

    Wong, John CT; Tang, Raymond SY; Teoh, Anthony YB; Sung, Joseph JY; Lau, James YW

    2017-01-01

    Background/study aims Laser lithotripsy can effectively fragment complicated biliary stones, but current cholangioscopes are limited by fragility, restricted mobility or moderate visual resolution. The efficacy and safety of a new digital single-operator peroral cholangioscope to guide laser lithotripsy were evaluated. Patients and methods In this prospective single-center series, consecutive patients with complicated biliary stones, defined as impacted stones > 1.5 cm in size and wider than the more distal common bile duct, or stones that failed extraction by basket mechanical lithotripsy, underwent ERCP and SpyGlass DS peroral cholangioscope (Boston Scientific, Marlborough, United States)-guided laser lithotripsy. Stone clearance rate and incidence of adverse events were determined. Results Seventeen patients (10 men, 7 women; median age 76 years) with a median biliary stone size of 2 cm underwent predominantly holmium:yttrium aluminum garnet laser lithotripsy, achieving a 94 % stone clearance rate over 1 median procedure. Lithotripsy was performed in 8 of 17 patients due to an impacted biliary stone. The remaining patients underwent lithotripsy due to prior failure of the basket mechanical lithotripter to capture or crush their stones. Post lithotripsy, 2 patients developed cholangitis and 1 patient with underlying COPD developed respiratory distress, all resolved with conservative management. There were no hemobilia, perforations, pancreatitis nor any deaths. Conclusion SpyGlass DS peroral cholangioscopy-guided laser lithotripsy is an efficient and safe modality for management of complicated biliary stones. PMID:28337482

  19. Laser lithotripsy: experience with different laser systems in the treatment of urinary calculi

    NASA Astrophysics Data System (ADS)

    Muschter, Rolf; Knipper, Ansgar; Maghraby, Hisham; Thomas, Stephen

    1990-06-01

    Two different systems for laserlithotripsy - the Q-switched Nd:YAG laser with an optomechanical coupler and the flashlamp pumped dye laser with integrated optical feedback mechanism are in clinical use for the treatment of urinary calculi at the Department of Urology of the Medical University of LUbeck. Seventy-five patients with ureteral calculi have been treated by laser lithotripsy. Eleven of 15 treatments using the Nd:YAG laser have been performed under visual control with the help of a rigid ureteroscope of 11.5 F. Thirty-five of 42 treatments with the dye laser were carried out with the help of a rigid ureteroscope of 9.5 F. Four patients with the Nd:YAG laser and 7 patients with the dye laser, respectively, have been treated without visual control using a flexible application system and fluoroscopy alone. Both systems showed excellent results. Fourteen of 15 laser lithotripsies with the Nd:YAG laser were successful showing complete (4 cases) or partial (10 cases) fragmentation. The analysis of the failure showed calcium oxalate monohydrate. Thirty-eight of 42 laser 1 ithotripsies with the dye laser were successful. Fragmentation was complete in 26 and partial in 12 cases. The 4 calculi which proved to be failures were all of pale color and 2 of them consisted of cystine alone. Both laser systems are suitable for the treatment of ureteral calculi under visual control or by blind application using fluoroscopy. No serious side effects of the treatment have been observed. Treatment results are satisfactory. Problems may occur in calculi of hard structure using the Nd:YAG laser due to its limited energy and in pale-colored stones using the dye laser due to poor absorption of the laser energy.

  20. Thulium fiber laser lithotripsy using small spherical distal fiber tips

    NASA Astrophysics Data System (ADS)

    Wilson, Christopher R.; Hardy, Luke A.; Kennedy, Joshua D.; Irby, Pierce B.; Fried, Nathaniel M.

    2016-02-01

    This study tests a 100-μm-core fiber with 300-μm-diameter ball tip during Thulium fiber laser (TFL) lithotripsy. The TFL was operated at 1908 nm wavelength with 35-mJ pulse energy, 500-μs pulse duration, and 300-Hz pulse rate. Calcium oxalate/phosphate stone samples were weighed, laser procedure times measured, and ablation rates calculated for ball tip fibers, with comparison to bare tip fibers. Photographs of ball tips were taken before and after each procedure to observe ball tip degradation and determine number of procedures completed before need to replace fiber. Saline irrigation rates and ureteroscope deflection were measured with and without TFL fiber present. There was no statistical difference (P > 0.05) between stone ablation rates for single-use ball tip fiber (1.3 +/- 0.4 mg/s) (n=10), multiple-use ball tip fiber (1.3 +/- 0.5 mg/s) (n=44), and conventional single-use bare tip fibers (1.3 +/- 0.2 mg/s) (n=10). Ball tip durability varied widely, but fibers averaged > 4 stone procedures before decline in stone ablation rates due to mechanical damage at front surface of ball tip. The small fiber diameter did not impact ureteroscope deflection or saline flow rates. The miniature ball tip fiber may provide a cost-effective design for safe fiber insertion through the ureteroscope working channel and the ureter without risk of scope damage or tissue perforation, and without compromising stone ablation efficiency during TFL ablation of kidney stones.

  1. Treatment of ureteral calculus obstruction with laser lithotripsy in an Atlantic bottlenose dolphin (Tursiops truncatus).

    PubMed

    Schmitt, Todd L; Sur, Roger L

    2012-03-01

    An adult female bottlenose dolphin (Tursiops truncatus) presented with acute anorexia secondary to progressive azotemia (blood urea nitrogen = 213 mg/dl, creatinine [Cr] = 9.5 mg/dl) and electrolyte abnormalities (K = 7.4 mEq/L). It was later diagnosed with postrenal obstruction secondary to bilaterally obstructing ureteral calculi seen on ultrasound. Treatment of the obstruction required two endoscopic procedures, cystoscopy for ureteral stent placement and ureteroscopy to perform intracorporeal lithotripsy on the obstructing calculi. Before the first procedure, the dolphin's azotemia was stabilized with aggressive fluid therapy, peritoneal dialysis, and treatment for acidosis. Diuresis subsequent to the fluid therapy enabled passage of the right obstructing urolith. For both endoscopic procedures, the dolphin was placed in left lateral recumbency due to the peritoneal dialysis catheter in the right retroperitoneal region. For the first procedure, a 12-French (Fr) flexible cystoscope was inserted retrograde into the bladder via the urethra, whereupon a calculus was seen obstructing the left ureteral orifice. A 4.8-Fr, 26-cm double-pigtail ureteral stent was placed up the left ureter to relieve the postrenal obstruction. Inadvertent proximal migration of the left ureteral stent occurred during the procedure. However, renal parameters (serum Cr = 5.8, K = 5.4) improved significantly by the next day. For the second procedure, 28 hr later, ureteroscopy was performed to treat the calculus and replace the existing stent with a longer stent. The left ureteral calculus was pulverized into tiny fragments by using a holmium:yttrium-aluminum-garnet laser inserted through a 6.9-Fr semirigid ureteroscope. The migrated stent was visualized in the distal left ureter and replaced with a 90-cm single-pigtail ureteral stent that was sutured exterior to the urogenital slit and removed 3 days later. Renal function normalized over the next several days, and the dolphin recovered over

  2. Single-operator cholangioscopy-guided laser lithotripsy in patients with difficult biliary and pancreatic ductal stones (with videos).

    PubMed

    Maydeo, Amit; Kwek, Boon Eu Andrew; Bhandari, Suryaprakash; Bapat, Mukta; Dhir, Vinay

    2011-12-01

    Scant data exist on the utility of the holmium:yttrium-aluminum-garnet laser for the treatment of biliary or pancreatic duct stones. To evaluate the efficacy and safety of fiberoptic probe and catheter system-guided holmium laser lithotripsy of difficult biliary and pancreatic duct stones. Prospective study. Tertiary-care referral center. This study involved 64 patients who underwent holmium laser stone fragmentation. A total of 64 patients (60 bile duct stones, 4 pancreatic duct stones) underwent endoscopic retrograde stone fragmentation with a holmium laser and a fiberoptic probe and catheter system. The inclusion criterion for bile duct stones was stones not amenable to retrieval by mechanical lithotripsy and/or balloon sphincteroplasty or standard techniques. Pancreatic duct stones included in this study were not amenable to removal by stone retrieval basket or balloon. Rates of ductal clearance and procedural complications. All 64 patients had successful fragmentation of biliary and pancreatic duct stones with the holmium laser. Fifty of 60 patients (83.3%) had complete biliary duct clearance after a single session; 10 patients required an additional session. All pancreatic duct stones were fragmented in a single session. Mean duration of ERCP sessions was 45.9 minutes (range 30-90 minutes). Complications were mild and were encountered in 13.5% of patients; fever (n = 3), transient abdominal pain (n = 4), and biliary stricture (n = 1). No comparative treatment group. The fiberoptic probe and catheter system facilitates transpapillary access for holmium laser fragmentation of difficult biliary and pancreatic duct stones. The technique is safe and highly effective for single-setting duct clearance. Complications are minimal and transient. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  3. Differentiation of tissue and kidney stones for laser lithotripsy using different spectroscopic approaches

    NASA Astrophysics Data System (ADS)

    Lange, Birgit; Cordes, Jens; Brinkmann, Ralf

    2015-07-01

    Holmium lasers are nowadays the gold standard for endoscopic laser lithotripsy. However, there is a risk of damaging or perforating the ureter or kidney tissue when the vision is poor. An automatic tissue/stone differentiation would improve the handling and safety of the procedure. To achieve this objective, an easy and robust real-time discrimination method has to be found which can be used to realize a feedback loop to control the laser system. Two possible approaches have been evaluated: White light reflectance and fluorescence spectroscopy. In both cases, we use the treatment fiber for detection and evaluate the possibility to decide whether the fiber is placed in front of tissue or calculus by the signal that is delivered by the surface in front of it. White light reflectance spectroscopy uses the standard light source for endourologic surgeries: Radiation of a Xenon light source is coupled to the ureteroscope via a liquid light guide. The part of the white light that is reflected back into the fiber is spectroscopically analyzed. In a clinical proof of concept study reflection signals were measured in vivo in 8 patients. For differentiation of stone and tissue via autofluorescence, excitation as well as detection was done via the treatment fiber. A suitable excitation wavelength was chosen with in vitro measurements (UV / visible) on several human renal calculi and porcine tissues. For verification of the positive results with green excitation in a clinical proof of concept study, a measurement set-up was realized which allows the recording of fluorescence signals during an endourological intervention.

  4. Diode laser and endoscopic laser surgery.

    PubMed

    Sullins, Kenneth E

    2002-05-01

    Two functionally important differences exist between the diode laser and the carbon dioxide (CO2) laser (used more commonly in small animal surgery). Diode laser energy is delivered through a quartz fiber instead of being reflected through an articulated arm or waveguide. Quartz fibers are generally more flexible and resilient than waveguides and can be inserted through an endoscope for minimally invasive procedures. Laser-tissue interaction is the other significant difference. The CO2 laser is completely absorbed by water, which limits the effect to visible tissue. The diode wavelength is minimally absorbed by water and may affect tissue as deep as 10 mm below the surface in the free-beam mode. With proper respect for the tissue effect, these differences can be used to the advantage of the patient.

  5. Ureteropyeloscopy and homium: YAG laser lithotripsy for treatment of ureteral calculi (report of 356 cases)

    NASA Astrophysics Data System (ADS)

    Wu, Zhong; Din, Qiang; Jiang, Hao-wen; Zen, Jing-cun; Yu, Jiang; Zhang, Yuanfang

    2005-07-01

    Objective: To evaluate the efficacy and safety of holmium YAG laser lithotripsy for the treatment of ureteral calculi. Methods: A total of 356 patients underwent ureteropyeloscopic lithotripsy using holmium YAG laser with a semirigid uretesopyeloscope, 93 upper, 135 middle, and 128 lower ureteral stones were treated. Results: The overall successful fragmentation rate for all ureteral stones in a single session achieved 98% (349/356). The successful fragmentation rate stratified by stone location was 95% 88/93 in the upper ureter, 99% (134/135) in the mid ureter , and 99%(127/128) in the distal ureter. 12 cases with bilateral ureteral stones which caused acute renal failure and anuria were treated rapidly and effectively by the holmium YAG laser lithotripsy. No complications such as perforation and severe trauma were encountered during the operations. 2 weeks 17months (with an average of 6.8 month ) follow up postoperatively revealed that the overall stone-free rate was 98%(343/349) and no ureteral stenosis was found. Conclusions Holmium YAG laser lithotripsy is a highly effective, minimally invasive and safe therapy for ureteral calculi. It is indicated as a first choice of treatment for patients with ureteral calculi, especially for the ones with mid- lower levels of ureteral calculi.

  6. Cost-effectiveness comparison of ureteral calculi treated with ureteroscopic laser lithotripsy versus shockwave lithotripsy.

    PubMed

    Cone, Eugene B; Pareek, Gyan; Ursiny, Michal; Eisner, Brian

    2017-01-01

    To evaluate the cost-effectiveness of shockwave lithotripsy (SWL) versus ureteroscopic lithotripsy (URS) for patients with ureteral stones less than 1.5 cm in diameter. Patient age, stone diameter, stone location, and stone-free status were recorded for patients treated with SWL or URS for ureteral stones under 1.5 cm over a 1 year period. Institutional charges were obtained from in-house billing. A decision analysis model was constructed to compare the cost-effectiveness of SWL and URS using our results and success rates for modeling. Three separate models were created to reflect differing practice patterns. A total of 113 patients were included-51 underwent SWL and 62 underwent URS as primary treatment. Single procedure stone-free rates for SWL and URS were 47.1 and 88.7 %, respectively (p < 0.002). Decision analysis modeling demonstrated cost-effectiveness of SWL when SWL single procedure stone-free rates (SFR) were greater than or equal to 60-64 % or when URS single procedure SFRs were less than or equal to 57-76 %, depending on practice patterns. This retrospective study revealed superior SFR for ureteral stones less than 1.5 cm treated with URS compared to SWL. Our decision analysis model demonstrated that when SFR for SWL is less than 60-64 % or is greater than 57-76 % for URS, SWL is not a cost-effective treatment option. Based on these findings, careful stratification and selection of stone patients may enable surgeons to increase the cost-effectiveness of SWL.

  7. New tunable flashlamp-pumped solid state Ti:sapphire laser for laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Jiang, Zhi X.; Giannetas, V.; Charlton, Andrew; King, Terence A.

    1993-05-01

    Laser pulses from a flashlamp pumped, solid state Ti:sapphire laser (Vuman, free running untuned wavelength 792 nm, 2 microseconds pulse width and up to 240 mJ pulse energy) have been successfully and efficiently coupled into thin optical fibers. The coupling efficiency can be up to 67% for 300 micron and 43% for 200 micron core diameter optical fibers. With these two optical fibers in vitro laser lithotripsy has been performed successfully on various human calculi including gall bladder, kidney, ureter and salivary duct stones. The bright white flash of the induced plasma emission, strong shock waves, fiber recoil and stone propulsion and the splattering of the stone chips have been observed during the calculi fragmentation.

  8. Holmium-YAG laser for gall stone fragmentation: an endoscopic tool.

    PubMed Central

    Blomley, M J; Nicholson, D A; Bartal, G; Foster, C; Bradley, A; Myers, M; Man, W; Li, S; Banks, L M

    1995-01-01

    A systematic review of the 2.1 mu holmium-YAG laser for gall stone lithotripsy was undertaken. This infrared laser, which can be used endoscopically and percutaneously, has safety advantages over other lasers and has potential as a general purpose vascular and surgical tool. Twenty nine gall stones (mean mass 1.3 g) were fragmented in vitro using pulse energies of 114 to 159 mJ/pulse at 5 Hz with a 0.6 mm fibre, while being held in an endoscopy basket. All stones were successfully fragmented, requiring an average of 566 pulses with a 5 Hz pulse repetition frequency. The number of pulses required increased with gall stone size and mass (p < 0.01), and decreased with both pulse energy (p < 0.01) and operator experience (p < 0.05). The biochemical content of the stone did not significantly affect the number of pulses needed. The potential hazard of the laser to the biliary endothelium was investigated. At the pulse energies used, five pulses at close contact penetrated into the serosa of fresh gall bladder wall. No damage was seen when two pulses were fired. This laser shows considerable promise in gall stone lithotripsy. Until further safety data are available, however, its use with endoscopic vision is advised. Images Figure 3 Figure 4 PMID:7698706

  9. EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY AND ENDOSCOPIC URETERAL STENT PLACEMENT IN AN ASIAN SMALL-CLAWED OTTER (AONYX CINEREA) WITH NEPHROLITHIASIS.

    PubMed

    Wojick, Kimberlee B; Berent, Allyson C; Weisse, Chick W; Gamble, Kathryn C

    2015-06-01

    Urolithiasis is a significant disease concern in Asian small-clawed otters (Aonyx cinerea), with over 60% of captive animals affected. Bilateral ureteral stent placement, using endoscopic and fluoroscopic guidance, and extracorporeal shock wave lithotripsy (ESWL) were performed as salvage procedures in a 13-yr-old intact female Asian small-clawed otter following a 7-yr history of nephrolithiasis and progressive renal insufficiency. Following the procedure, radiographs revealed a slight shifting of urolith position, although a decrease in urolith mass was not observed. As a result of declining quality of life related to severe osteoarthritis, the otter was euthanized 5 wk after the procedure. While this treatment approach was unsuccessful in this case, the technique was clinically feasible, so ESWL and ureteral stent placement may remain a consideration for other individuals of this species presented earlier in the course of this disease.

  10. The Efficacy of Percutaneous Nephrolithotomy Using Pneumatic Lithotripsy vs. the Holmium Laser: a Randomized Study.

    PubMed

    Liu, Chaoying; Zhou, Houyong; Jia, Weisheng; Hu, Hua; Zhang, Heng; Li, Longkun

    2017-08-01

    The objective of the study is to compare the efficacy of percutaneous nephrolithotomy using holmium laser vs pneumatic lithotripsy. From August 2010 to March 2014, 200 patients with double kidney and single kidney stones without previous operations or other diseases were randomized into two groups according to the type of lithotripter used: pneumatic (n = 100) and laser (n = 100). The preoperative, intraoperative, and post-operative follow-up findings were analyzed and compared. The average stone size was similar in both the pneumatic and holmium laser lithotripsy groups (202.8 ± 52.6 mm(2) vs. 200.3 ± 50.8 mm(2)). No significant difference was found between the operation time for the two groups (55.9 ± 16.5 min vs. 62.4 ± 17.6 min). The concentrations of creatinine in both groups increased 2-24 h after the operation and decreased to a normal level 1-4 days after the operation in both groups. Renal diuretic scan revealed that the peak and the renal index were both abnormal after the operation but became normal 4 days after the operation in both groups. No significant difference of creatinine concentration or the diuresis renogram was observed between the two groups. However, two cases in the holmium laser group had almost lost the renal function of the operated kidney 1 year later. Both pneumatic and holmium laser lithotripsy can be associated with acute renal injury in some patients after the operation without any significant difference. However, some infrequent severe renal function damage in laser lithotripsy should be noted.

  11. Traumatic aniridia during endoscopic laser cycloablation.

    PubMed

    Gayton, J L

    1998-01-01

    Endoscopic laser cycloablation can be effective in treating glaucoma. The Micro probe endoscopic laser permits excellent visualization of the ciliary processes. However, the surgeon can not simultaneously view through the probe and see the probe's location in the eye through the surgical microscope. An iris adhesion with the probe led to total aniridia in the case reported. Having an assistant watch the operative monitor or devising a system that allows the surgeon to watch both monitors could prevent this complication.

  12. Pneumatic versus laser ureteroscopic lithotripsy: a comparison of initial outcomes and cost.

    PubMed

    Demir, Aslan; Karadağ, Mert Ali; Ceçen, Kurşat; Uslu, Mehmet; Arslan, Omer Erkam

    2014-11-01

    To audit the cost of laser versus pneumatic semirigid ureteroscopic lithotripsy and to analyze their relative initial outcomes and cost. Hundred and eighty-seven patients who underwent semirigid ureteroscopic lithotripsy were analyzed retrospectively in terms of age and sex of the patients; location and size of the stones; the type of probe and ancillary equipment such as guide wire, basket catheter, JJ stent requirements; irrigation amount; operation time; the cost of the anesthesia and further treatments such as a JJ stent removal operation and shock wave lithotripsy requirements and their costs. Two groups were formed based on this type of lithotripters, pneumatic and laser lithotripsy. Operation times (min.) in terms of the stone size, for stones <100 and >100 mm(2) were 20.75 ± 10.78 and 25.82 ± 14.23, respectively (p = 0.007). Operation times for the pneumatic and laser groups were 33.05 ± 11.36 and 15.25 ± 6.14, respectively (p < 0.05).The stone-free rates for pneumatic and laser groups were 89.6 % (n = 69) and 98.2 % (n = 108), respectively (p = 0.01). The mean cost of the operations for each of the study groups was 261.5 ± 66.13 and 311.7 ± 51.97 US$, respectively (p = 0.001). The mean cost in terms of the stone size, for stones <100 and >100 mm(2), was 272.86 ± 53.05 and 323.71 ± 66.88 US$, respectively (p = 0.01). It seems that usage of laser lithotripsy (LL) in patients with ureteral stones is more effective than pneumatic lithotripsy (PL) in terms of operation time and SF rate. On the other hand, the mean cost of LL seems to be more expensive than PL. Urologists should think these parameters before the choice of these two treatment modalities. The higher the effectiveness, the greater the cost.

  13. Transurethral holmium-YAG laser lithotripsy for large symptomatic prostatic calculi: initial experience.

    PubMed

    Goyal, Neeraj Kumar; Goel, Apul; Sankhwar, Satyanarayan

    2013-08-01

    Symptomatic prostatic calculi are a rare clinical entity with wide range of management options, however, there is no agreement about the preferred method for treating these symptomatic calculi. In this study we describe our experience of transurethral management of symptomatic prostatic calculi using holmium-YAG laser lithotripsy. Patients with large, symptomatic prostatic stones managed by transurethral lithotripsy using holmium-YAG laser over 3-year duration were included in this retrospective study. Patients were evaluated for any underlying pathological condition and calculus load was determined by preoperative X-ray KUB film/CT scan. Urethrocystoscopy was performed using 30° cystoscope in lithotomy position under spinal anesthesia, followed by transurethral lithotripsy of prostatic calculi using a 550 μm laser fiber. Stone fragments were disintegrated using 100 W laser generators (VersaPulse PowerSuite 100 W, LUMENIS Surgical, CA). Larger stone fragments were retreived using Ellik's evacuator while smaller fragments got flushed under continuous irrigation. Five patients (median age 42 years) with large symptomatic prostatic calculi were operated using the described technique. Three patients had idiopathic stones while rest two had bulbar urethral stricture and neurogenic bladder, respectively. Median operative time was 62 min. All the patients were stone free at the end of procedure. Median duration of catheterization was 2 days. Significant improvement was observed in symptoms score and peak urinary flow and none of the patient had any complication. Transurethral management using holmium-YAG laser lithotripsy is a safe and highly effective, minimally invasive technique for managing symptomatic prostatic calculi of all sizes with no associated morbidity.

  14. Effectiveness and Safety of Ureteroscopic Holmium Laser Lithotripsy for Upper Urinary Tract Calculi in Elderly Patients.

    PubMed

    Yoshioka, Takashi; Otsuki, Hideo; Uehara, Shinya; Shimizu, Toshihiro; Murao, Wataru; Fujio, Koji; Fujio, Kei; Wada, Koichiro; Araki, Motoo; Nasu, Yasutomo

    2016-06-01

    Upper urinary tract calculi are common; however, there is no recommended treatment selection for elderly patients. Ureteroscopic holmium laser lithotripsy (URS lithotripsy) is minimally invasive, and it provides a high stone-free rate (SFR) treatment for upper urinary tract calculi. Here, we retrospectively evaluated the surgical outcomes of URS lithotripsy after dividing the 189 cases into 3 groups by patient age: the '<65 group' (<65 years old, n=108), the '65-74 group' (65-74 years old, n=42), and the ' 75 group' ( 75 years old, n=39). The patients' characteristics, stone status, and perioperative outcomes were assessed. The 65-74 group and the 75 group had a significantly higher prevalence of hypertension compared to the<65 group. Compared to the<65 group, the 65-74 group had a significantly higher prevalence of hyperlipidemia, and the 75 group had significantly higher the American Society of Anesthesiologists (ASA) scores. Despite these preoperative risk factors, SFR and postoperative pyelonephritis in the 65-74 group and the 75 group were similar to those of the<65 group. In conclusion, URS lithotripsy is the preferred treatment for upper urinary tract calculi, even for elderly patients who have multiple preoperative risk factors.

  15. Use of NTrap during ureteroscopic Holmium:YAG laser lithotripsy of upper ureteral calculi.

    PubMed

    Feng, Chenchen; Ding, Qiang; Jiang, Haowen; Gao, Peng; Wen, Hui; Gu, Bin; Wu, Zhong

    2012-03-01

    We investigated the effectiveness of NTrap in prevention of stone retropulsion during ureteroscopic Ho:YAG laser lithotripsy of upper ureteral calculi. A total of 308 patients with upper ureteral stones treated by semirigid ureteroscopic Ho:YAG laser were stratified into two groups in which 152 patients without NTrap use were assigned to Group I and 156 patients with NTrap use were assigned to Group II. Patient gender, age, stone size, operative time, and parameters for stone migration were compared between the two groups. The difference in patient gender, age, and stone size were insignificant between the two groups. Longer operative duration (P = 0.000) was observed in Group II. Group II showed a higher intraoperative success rate of lithotripsy (P = 0.000) and a lower postoperative stone residual rate (P = 0.070) compared with Group I. The overall success rate was higher in Group II (P = 0.000). NTrap is an effective occlusive device against upper ureteral calculi retropulsion during ureteroscopic Ho:YAG laser lithotripsy.

  16. Determinants of holmium:yttrium-aluminum-garnet laser time and energy during ureteroscopic laser lithotripsy.

    PubMed

    Molina, Wilson R; Marchini, Giovanni S; Pompeo, Alexandre; Sehrt, David; Kim, Fernando J; Monga, Manoj

    2014-04-01

    To evaluate the association of preoperative noncontrast computed tomography stone characteristics, laser settings, and stone composition with cumulative holmium:yttrium-aluminum-garnet (Ho:YAG) laser time/energy. We retrospectively reviewed patients who underwent semirigid/flexible ureteroscopy and Ho:YAG laser lithotripsy (200 or 365 μm laser fiber; 0.8-1.0 J energy; and 8-10 Hz rate) at 2 tertiary care centers (April 2010-May 2012). Studied parameters were as follows: patient's characteristics; stone characteristics (location, burden, hardness, and composition); total laser time and energy; and surgical outcomes. One hundred patients met our inclusion criteria. Mean stone size was 1.01 ± 0.42 cm and volume 0.33 ± 0.04 cm(3). Mean stone radiodensity was 990 ± 296 HU, and Hounsfield units density 13.8 ± 6.0 HU/mm. All patients were considered stone free. Stone size and volume had a significant positive correlation with laser energy (R = 0.516, P <.001; R = 0.621, P <.001) and laser time (R = 0.477, P <.001; R = 0.567, P <.001). When controlling for stone size, only the correlation between HU and laser time was significant (R = 0.262, P = .011). In the multivariate analysis, with exception of stone composition (P = .103), all parameters significantly increased laser energy (R(2) = 0.524). Multivariate analysis revealed a positive significant association of laser time with stone volume (P <.001) and Hounsfield units density (P <.001; R(2) = 0.512). In multivariate analysis for laser energy, only calcium phosphate stones required less energy to fragment compared with uric acid stones. No significant differences were found in the multivariate laser time model. Ho:YAG laser cumulative energy and total time are significantly affected by stone dimensions, hardness location, fiber size, and power. Kidney location, laser fiber size, and laser power have more influence on the final laser energy than on the total laser time. Calcium phosphate stones require less laser

  17. Stone/tissue differentiation for Holmium laser lithotripsy using autofluorescence: Clinical proof of concept study.

    PubMed

    Lange, Birgit; Jocham, Dieter; Brinkmann, Ralf; Cordes, Jens

    2017-04-01

    Holmium laser lithotripsy is the gold standard for intracorporeal fragmentation of urinary calculi. Usually, a visible beam is superimposed on the IR treatment laser as an aiming beam to guide the surgeon. In vitro tests showed that this aiming beam (532 nm, power <1 mW) excites strong fluorescence on human calculi. Tissue, in contrast, emitted much weaker fluorescence. If this is verified in vivo, the fluorescence signal induced by the aiming beam could be used to implement a feedback loop, preventing the Holmium laser being fired on tissue. Fluorescence signals of 67 tissue and 68 stone spots were measured in a clinical proof of concept study with eight patients. For this, a modulated excitation/detection scheme (lock-in technique) was implemented. A frequency-doubled, diode-pumped solid-state laser module (532 nm, modulation frequency 66 Hz, average power 0.3 mW) was coupled via a dichroic mirror with the Holmium lithotripsy laser into the treatment fiber. The fluorescence signal entering the treatment fiber was detected via another dichroic mirror with a photodiode and a lock-in amplifier. In most instances (94%), the calculus of a patient gave a signal which was at least twice the maximum signal of ureteral tissue. The results of our proof of concept study indicate that measuring the fluorescence signal of a green aiming beam could be used to implement a feedback loop for Holmium laser lithotripsy. Preventing the laser being fired on tissue, this would increase the safety of the procedure. Lasers Surg. Med. 49:361-365, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. Percutaneous nephroscopic with holmium laser and ultrasound lithotripsy for complicated renal calculi.

    PubMed

    Gu, Zhengqin; Qi, Jun; Shen, Haibo; Liu, Jianhe; Chen, Jianhua

    2010-07-01

    The aim of this work is to validate the clinical efficacy of the high-power holmium:YAG laser with percutaneous nephrolithotripsy (PCNL) in combination with ultrasound lithotripsy for complicated renal calculi. From November 2006 to December 2007, 60 patients with complicated renal calculi were treated with PCNL, where an F24 standard renal access tract was established by percutaneous renal puncture under the guidance of B-mode ultrasound, and stones were fragmented and cleared by high-power holmium laser in combination with ultrasound under an F20.8 nephroscope. Of the 60 patients with complicated renal calculi, 20 were complete staghorn calculi and 30 were partial staghorn calculi, of which six patients were accompanied with renal insufficiency; two were solitary calculi, and eight were caliceal diverticular calculi. Calculi were removed by one attempt in 49 patients and by two attempts in 11 patients; through one tract in 50 patients and through two and three tracts in ten patients. The stone-free rate was 81.7%. No injury to the pleura and abdominal organs occurred during the intraoperative puncture. No postoperative blood transfusion was needed in any patient, nor did fever and secondary hemorrhage occur. The mean operation duration was 98 min (range, 60-150 min), and the mean lithotripsy time was 45 min (range, 30-85 min). Additional postoperative extracorporeal shock wave lithotripsy (ESWL) was performed on six patients. High-power holmium laser PCNL in combination with ultrasound lithotripsy is safe, effective, and minimally invasive, with a high stone-free rate, especially for complicated renal calculi.

  19. Combining ultrasonography and noncontrast helical computerized tomography to evaluate Holmium laser lithotripsy

    PubMed Central

    Mi, Jia; Li, Jie; Zhang, Qinglu; Wang, Xing; Liu, Hongyu; Cao, Yanlu; Liu, Xiaoyan; Sun, Xiao; Shang, Mengmeng; Liu, Qing

    2016-01-01

    Abstract The purpose of the study was to establish a mathematical model for correlating the combination of ultrasonography and noncontrast helical computerized tomography (NCHCT) with the total energy of Holmium laser lithotripsy. In this study, from March 2013 to February 2014, 180 patients with single urinary calculus were examined using ultrasonography and NCHCT before Holmium laser lithotripsy. The calculus location and size, acoustic shadowing (AS) level, twinkling artifact intensity (TAI), and CT value were all documented. The total energy of lithotripsy (TEL) and the calculus composition were also recorded postoperatively. Data were analyzed using Spearman's rank correlation coefficient, with the SPSS 17.0 software package. Multiple linear regression was also used for further statistical analysis. A significant difference in the TEL was observed between renal calculi and ureteral calculi (r = –0.565, P < 0.001), and there was a strong correlation between the calculus size and the TEL (r = 0.675, P < 0.001). The difference in the TEL between the calculi with and without AS was highly significant (r = 0.325, P < 0.001). The CT value of the calculi was significantly correlated with the TEL (r = 0.386, P < 0.001). A correlation between the TAI and TEL was also observed (r = 0.391, P < 0.001). Multiple linear regression analysis revealed that the location, size, and TAI of the calculi were related to the TEL, and the location and size were statistically significant predictors (adjusted r2 = 0.498, P < 0.001). A mathematical model correlating the combination of ultrasonography and NCHCT with TEL was established; this model may provide a foundation to guide the use of energy in Holmium laser lithotripsy. The TEL can be estimated by the location, size, and TAI of the calculus. PMID:27930563

  20. [Management of calyceal diverticular calculi with stenotic infundibulum by flexible ureteroscopic holmium laser infundibulectomy and lithotripsy].

    PubMed

    Liu, Ke; Xiao, Chun-lei; Liu, Yu-qing; Hao, Yi-chang; Zhang, Shu-dong; Tian, Yu; Ma, Lu-lin

    2015-08-18

    To evaluate the efficacy and safety of flexible ureteroscopic holmium laser lithotripsy in treating calyceal diverticular calculi with stenotic infundibulum and to present our initial experience. From Nov. 2012 to Nov. 2014, 10 patients with stone-bearing calyceal diverticulum and stenotic infundibulum underwent flexible ureteroscopic holmium laser lithotripsy in our hospital, including 3 female patients and 7 male patients with an average age of 36.9 years (range: 20 to 62 years). There were 6 patients with right side while 4 patients with left side calyceal diverticular calculi. The average cumulative stone size was (1.33±0.43) cm. Five patients underwent extracorporeal shock wave lithotripsy (ESWL) before hospital admission but no stone was discharged. All the patients received intravenous urography (IVU) and CT-urography (CTU) preoperatively and underwent double-J stents placement 2 weeks before operations. A digital-fiber flexible ureteroscopy and 200 μm holmium laser fiber were used for treatment. Surgeries began with routine flexible ureteroscopy and methylene blue injection was used to identify the small ostium of infundibulum. Then infundibulectomy followed by lithotripsy was performed. All the patients receive double-J stents placement and traditional Chinese medicine for 1 to 3 months after operations. The stone clearance was estimated by kidney ureter bladder (KUB) within 3 months' follow up. The locations of calyceal diverticulum were upper pole in 7 patients, and interpolar regions in 4 patients. The average operation time was (123.7±59.6) min, and the average estimated blood loss was (29.3±32.1) mL. Successful flexible ureteroscopic holmium laser infundibulectomies were performed in all the 10 patients. Success rate was 100%. The stone clearance rates for 1 and 3 months after surgery were 50.0% and 80.0%, respectively, which were observed by KUB follow-up. Two patients had serious post-operative fever (>38.0 °C) in coexistence with chills. The

  1. Laser scanning endoscope for diagnostic medicine

    NASA Astrophysics Data System (ADS)

    Ouimette, Donald R.; Nudelman, Sol; Spackman, Thomas; Zaccheo, Scott

    1990-07-01

    A new type of endoscope is being developed which utilizes an optical raster scanning system for imaging through an endoscope. The optical raster scanner utilizes a high speed, multifaceted, rotating polygon mirror system for horizontal deflection, and a slower speed galvanometer driven mirror as the vertical deflection system. When used in combination, the optical raster scanner traces out a raster similar to an electron beam raster used in television systems. This flying spot of light can then be detected by various types of photosensitive detectors to generate a video image of the surface or scene being illuminated by the scanning beam. The optical raster scanner has been coupled to an endoscope. The raster is projected down the endoscope, thereby illuminating the object to be imaged at the distal end of the endoscope. Elemental photodetectors are placed at the distal or proximal end of the endoscope to detect the reflected illumination from the flying spot of light. This time sequenced signal is captured by an image processor for display and processing. This technique offers the possibility for very small diameter endoscopes since illumination channel requirements are eliminated. Using various lasers, very specific spectral selectivity can be achieved to optimum contrast of specific lesions of interest. Using several laser lines, or a white light source, with detectors of specific spectral response, multiple spectrally selected images can be acquired simultaneously. The potential for co-linear therapy delivery while imaging is also possible.

  2. Use of the Moses Technology to Improve Holmium Laser Lithotripsy Outcomes: A Preclinical Study

    PubMed Central

    Badaan, Shadie; Ibrahim, Ahmed; Andonian, Sero

    2017-01-01

    Abstract Objective: To evaluate in vitro and in vivo effects of Moses technology in Holmium laser and to compare it with the Regular mode in terms of lithotripsy efficiency and laser-tissue interactions. Methods: The Lumenis® Pulse™ P120H holmium laser system together with Moses D/F/L fibers were used to compare the Regular mode with the Moses modes in stone retropulsion by using a high-speed camera, and stone ablation efficiency. In addition, a porcine ureteroscopy model was used to assess stone fragmentation and dusting as well as laser-tissue interaction with the ureteral wall. Results: After a laser pulse, in vitro stone displacement experiments showed a significant reduction in retropulsion when using the Moses mode. The stone movement was reduced by 50 times at 0.8 J and 10 Hz (p < 0.01). The pronounced reduction of retropulsion in the Moses mode was clearly observed during fragmentation setting (high energy) and dusting (low energy, high Hz). In addition, stone fragmentation tests showed that the Moses modes resulted in a significantly higher ablation volume when compared with the Regular mode (160% higher; p < 0.001). In vivo assessment also supported the reduction in retropulsion when treating stones in the porcine kidney. Histological analysis of the porcine ureter after direct lasing in the Moses mode suggested less damage than in the Regular mode. Conclusions: The Moses technology resulted in more efficient laser lithotripsy, in addition to significantly reduced stone retropulsion, and displayed a margin of safety that may result in a shorter procedural time and safer lithotripsy. PMID:28340540

  3. Study of cavitation bubble dynamics during Ho:YAG laser lithotripsy by high-speed camera

    NASA Astrophysics Data System (ADS)

    Zhang, Jian J.; Xuan, Jason R.; Yu, Honggang; Devincentis, Dennis

    2016-02-01

    Although laser lithotripsy is now the preferred treatment option for urolithiasis, the mechanism of laser pulse induced calculus damage is still not fully understood. This is because the process of laser pulse induced calculus damage involves quite a few physical and chemical processes and their time-scales are very short (down to sub micro second level). For laser lithotripsy, the laser pulse induced impact by energy flow can be summarized as: Photon energy in the laser pulse --> photon absorption generated heat in the water liquid and vapor (super heat water or plasma effect) --> shock wave (Bow shock, acoustic wave) --> cavitation bubble dynamics (oscillation, and center of bubble movement , super heat water at collapse, sonoluminscence) --> calculus damage and motion (calculus heat up, spallation/melt of stone, breaking of mechanical/chemical bond, debris ejection, and retropulsion of remaining calculus body). Cavitation bubble dynamics is the center piece of the physical processes that links the whole energy flow chain from laser pulse to calculus damage. In this study, cavitation bubble dynamics was investigated by a high-speed camera and a needle hydrophone. A commercialized, pulsed Ho:YAG laser at 2.1 mu;m, StoneLightTM 30, with pulse energy from 0.5J up to 3.0 J, and pulse width from 150 mu;s up to 800 μs, was used as laser pulse source. The fiber used in the investigation is SureFlexTM fiber, Model S-LLF365, a 365 um core diameter fiber. A high-speed camera with frame rate up to 1 million fps was used in this study. The results revealed the cavitation bubble dynamics (oscillation and center of bubble movement) by laser pulse at different energy level and pulse width. More detailed investigation on bubble dynamics by different type of laser, the relationship between cavitation bubble dynamics and calculus damage (fragmentation/dusting) will be conducted as a future study.

  4. Microscopic analysis of laser-induced proximal fiber tip damage during holmium:YAG and thulium fiber laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Wilson, Christopher R.; Hardy, Luke A.; Irby, Pierce B.; Fried, Nathaniel M.

    2016-04-01

    The thulium fiber laser (TFL) is being studied as an alternative to the standard holmium:YAG laser for lithotripsy. The TFL beam originates within an 18-μm-core thulium-doped silica fiber, and its near single mode, Gaussian beam profile enables transmission of higher laser power through smaller (e.g., 50- to 150-μm core) fibers than possible during holmium laser lithotripsy. This study examines whether the more uniform TFL beam profile also reduces proximal fiber tip damage compared with the holmium laser multimodal beam. Light and confocal microscopy images were taken of the proximal surface of each fiber to inspect for possible laser-induced damage. A TFL beam at a wavelength of 1908 nm was coupled into 105-μm-core silica fibers, with 35-mJ energy, and 500-μs pulse duration, and 100,000 pulses were delivered at each pulse rate setting of 50, 100, 200, 300, and 400 Hz. For comparison, single use, 270-μm-core fibers were collected after clinical holmium laser lithotripsy procedures performed with standard settings (600 mJ, 350 μs, 6 Hz). Total laser energy, number of laser pulses, and laser irradiation time were recorded, and fibers were rated for damage. For TFL studies, output pulse energy and average power were stable, and no proximal fiber damage was observed at settings up to 35 mJ, 400 Hz, and 14 W average power (n=5). In contrast, confocal microscopy images of fiber tips after holmium lithotripsy showed proximal fiber tip degradation, indicated by small ablation craters on the scale of several micrometers in all fibers (n=20). In summary, the proximal fiber tip of a 105-μm-core fiber transmitted up to 14 W of TFL power without degradation, compared to degradation of 270-μm-core fibers after transmission of 3.6 W of holmium laser power. The smaller and more uniform TFL beam profile may improve fiber lifetime, and potentially translate into lower costs for the surgical disposables as well.

  5. Nonstented versus routine stented ureteroscopic holmium laser lithotripsy: a prospective randomized trial.

    PubMed

    Shao, Yi; Zhuo, Jian; Sun, Xiao-Wen; Wen, Wei; Liu, Hai-Tao; Xia, Shu-Jie

    2008-10-01

    We conducted a prospective, randomized study to evaluate whether postoperative ureteral stenting is necessary after ureteroscopic holmium laser lithotripsy. A total of 115 consecutive patients with distal or middle ureteral calculi amenable to ureteroscopic holmium laser lithotripsy were prospectively randomized into stented group (n = 58) and nonstented group (n = 57). The stent was routinely placed in the treated ureter for 2 weeks. The outcomes were measured with postoperative patient symptoms, stone-free rates, early and late postoperative complications, and cost-effectiveness. The postoperative symptoms were measured with Ureteral Stent Symptom Questionnaire (USSQ). All patients completed a 12-week follow-up. There was no significant difference between two groups with respect to the patient age, stone size, stone location and mean operative time. According to the USSQ, the symptoms of the stented group were significantly worse compared to the nonstented group (P = 0.0001). In the stented group, two patients had high fever for 1 week after the operation, stent migration was found in two patients, and the stents had to be removed earlier in five patients because of severe pain or hematuria. The cost of the stented group was significantly higher than the nonstented group. The stone-free rate was 100% in both groups. No hydronephrosis or ureteral stricture was detected by intravenous pyelogram in the 12th week postoperative follow-up. In conclusion, we believe that routine stenting after ureteroscopic intracorporeal lithotripsy with the holmium laser is not necessary as long as the procedure is uncomplicated for distal or middle ureteral calculis less than 2 cm.

  6. Gallbladder stone inspection and identification for laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Makdisi, Yacob; Kokaj, Jahja O.

    1999-03-01

    Using high speed imaging techniques, the gall bladder stone immersed in liquid is detected and identified. The detection of the shock waves induced by laser power is reached by using interferometry technique. Using gall bladder and tissue images obtained by ultra-fast photography and time resolved laser fluorescence the correlation of correlation is performed. The tissue image is used to perform the correlation filter. Hence lower correlation output is used for firing of the laser power.

  7. Anti-reflection coated optical fibers for use in thulium fiber laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Wilson, Christopher R.; Kennedy, Joshua D.; Irby, Pierce B.; Fried, Nathaniel M.

    2017-02-01

    The Thulium fiber laser (TFL) is being studied as an alternative to Holmium:YAG laser for lithotripsy. The near single mode TFL beam profile enables transmission of higher laser power through smaller optical fibers than possible during Holmium laser lithotripsy. Current free-space coupling of collimated TFL output beam into a disposable silica fiber for ureteroscopy is limited by back-reflected light from the fiber input surface, which may result in laser shutoff or damage, if left unchecked. This study examines whether anti-reflection (AR) coated fibers may sufficiently reduce back-reflected light to prevent laser shutoff, increase fiber optic transmission, and potentially increase laser stone ablation rates as well. Fiber optic transmission and stone ablation studies were conducted comparing uncoated and AR-coated 105- and 200-μm-core fibers. Magnified images of proximal fiber surfaces were taken before and after each trial to examine for AR-coating damage. TFL wavelength of 1908 nm was coupled into silica fibers, with incrementally increasing pulse energy (5-35 mJ), fixed 500-μs pulse duration, and pulse rates of 50-300 Hz. For each pulse rate, 100,000 pulses were also delivered through the fibers to examine for potential damage. Back-reflection at proximal fiber surface was reduced from 3.25% with uncoated fibers to 0.06% with AR coated fibers. For both fiber diameters, output power was stable, and no proximal fiber damage was observed after delivery of 100,000 pulses at 35 mJ, 300 Hz, and 10.5 W average power. There was no significant difference in stone ablation rates between fiber diameters (105 vs. 200 μm) or bare or AR-coated fibers. Laser shutdown was not observed using AR-coated fibers, which reduce back-reflection and improve energy transmission, but do not improve stone ablation rates.

  8. Endoscopic laser recanalisation of presaccal canalicular obstruction

    PubMed Central

    Kuchar, A.; Novak, P.; Pieh, S.; Fink, M.; Steinkogler, F. J.

    1999-01-01

    AIM—To document the results of erbium (Er)-YAG laser treatment in presaccal canalicular obstruction in combination with the use of a flexible endoscope.
METHODS—For the first time an Er-YAG laser (Schwind, Sklerostom) was attached to a flexible endoscope (Schwind, Endognost) and used to recanalise a stenosis of the upper, lower, or common canaliculus. In 17 patients (mean age 41.5 (SD 11.9) years), 19 treatments (two bilateral) were performed. In all cases the scar was observed using the endoscope and was excised by laser ablation. A silicone intubation was performed in all cases. In addition to the endoscopy an irrigation was performed to prove the intactness of the lacrimal pathway system after laser treatment.
RESULTS—Membranous obstructions with a maximum length of 2.0 mm (14 procedures) in the canaliculus were opened easily using the laser, and the silicone intubation was subsequently performed without difficulty. Scars thicker than 2.0 mm could not be opened safely without canaliculus penetration (five procedures). Irrigation was positive in all cases up to the end of a 6 month period, providing the tubes remained in place. The maximum follow up is now 17 months (minimum 8 months) and in 16 cases (84.2%) the canaliculi are still intact.
CONCLUSION—Endoscopic laser treatment combined with silicone intubation enables us to recanalise presaccal stenoses of canaliculi under local anaesthesia up to a scar thickness of 2.0 mm. Best results can be achieved in cases where much tissue can be saved. Under such conditions this procedure can substitute for more invasive surgical techniques, especially a conjunctivo-dacryocystorhinostomy (CDCR).

 Keywords: laser recanalisation; presaccal canalicular obstruction; endoscopy PMID:10434867

  9. Advantages of laser application in endoscopic surgery.

    PubMed

    Hunter, J G

    1993-08-01

    This article discusses the various kinds of laser therapy used in endoscopic surgery and their respective indications. Following a brief introduction into the basics of laser-tissue-interaction it is shown how less expensive treatment modalities have narrowed the range of laser applications to very specific purposes. In upper gastrointestinal bleeding argon and KTP lasers are mainly used for treatment of pigmented gut lesions. In malignant disease the combined use of balloon dilatation and laser irradiation has proved efficient in restoring patency to the gastrointestinal tract. Argon and CO2 lasers are used by gynaecologists for ablation of endometrioma. In an assessment of future prospects it is concluded that the lasting value of the laser lies in its ability to selectively destroy pigmented pathologic tissues.

  10. Is flexible ureterorenoscopy and laser lithotripsy the new gold standard for lower pole renal stones when compared to shock wave lithotripsy: Comparative outcomes from a University hospital over similar time period

    PubMed Central

    Burr, Jacob; Ishii, Hiro; Simmonds, Nick

    2015-01-01

    Introduction Renal lower pole stones pose difficulty in management due to anatomical variation, stone size, hardness and patient demographics. Flexible ureterorenoscopy and laser lithotripsy (FURSL) and shock wave lithotripsy (SWL) are preferred for stones 1-2 cm in size. We wanted to compare the outcomes of FURSL and SWL for lower pole stones during the same time period. Material and methods All patients who were treated for lower pole stones with FURSL and SWL during a 19-month period were included. The stone free rate (SFR) was defined as ≤3 mm fragments on follow-up imaging or stone free endoscopically. Data was recorded in an excel spreadsheet with SPSS version 21 used for statistical analysis. Results A total of 161 lower pole procedures were done (93 SWL and 63 FURSL). The mean stone size for SWL (7.4 mm; range: 4-16 mm) was significantly smaller than for FURSL (13.4 mm; 4-53 mm). The mean operating time and hospital stay for FURSL was 65 minutes (range: 30-160 minutes) and 0.5 days (range: 0-7 days) respectively. The SFR was significantly better (p <0.001) for FURSL (n = 63, 93%) compared to SWL (n = 23, 25%). There were 4 (6%) complications (3 Clavien II and 1 Clavien I) in the FURSL group (2 urosepsis, 1 UTI and 1 stent pain). Three patients in the SWL group (Clavien I) were readmitted with renal colic but there were no other complications. Conclusions FURSL for lower pole stones seems to be a much better alternative than SWL with a high SFR even for larger stones and seems to be the new gold standard for lower pole stone management. PMID:26251738

  11. Outcomes of retrograde flexible ureteroscopy and laser lithotripsy for stone disease in patients with anomalous kidneys.

    PubMed

    Ugurlu, İbrahim Mesut; Akman, Tolga; Binbay, Murat; Tekinarslan, Erdem; Yazıcı, Özgür; Akbulut, Mehmet Fatih; Özgör, Faruk; Müslümanoğlu, Ahmet Yaser

    2015-02-01

    Due to the presence of structural and anatomical differences that accompany anomalous kidneys, currently available endourological modalities such as SWL and PNL may be insufficient, or additional laparoscopic assistance may be required. The present study aims to evaluate the efficacy and safety of retrograde flexible ureterorenoscopic stone treatment in patients with kidney anomalies. Over the last 3 years, 25 patients with renal stones in anomalous kidneys were consecutively treated by flexible ureterorenoscopy and holmium:YAG laser lithotripsy. Among the 25 patients, fiberoptic or digital flexible ureterorenoscopies were performed for the management of horseshoe kidneys (n = 3), cross-fused ectopic kidney (n = 1), renal ectopies [n = 13; associated with pelvic (n = 6) or lumbar kidneys (n = 7)], renal malrotations (n = 4), and duplicate ureters (n = 4). For lithotripsy, 200 or 273 µm probes were used, and for stone retraction 1.3-1.9 Fr ZeroTip baskets were used. Success was defined as the complete absence of stones as evaluated with a CT scan 1 month after the operation. The mean patient age was 39.4 ± 15.75 years, and the mean stone size was 194.64 ± 103.93 mm(2) (range 50-393). Complete stone clearance was achieved in 16 patients (64%) after a single session. Seven of the patients with residual stones underwent a second session and the remaining three patients were subsequently treated with SWL. The overall complete clearance rate was 88% (22 patients) with ancillary procedures. There were no serious postoperative complications except for one case (4%) of urosepsis. Flexible ureterorenoscopy with holmium laser lithotripsy is a safe option for the treatment of renal stones in anomalous kidneys with satisfactory success rates.

  12. Ureteroscopy and holmium:YAG laser lithotripsy: an emerging definitive management strategy for symptomatic ureteral calculi in pregnancy

    NASA Astrophysics Data System (ADS)

    Watterson, James D.; Girvan, Andrew R.; Beiko, Darren T.; Nott, Linda; Wollin, Timothy A.; Razvi, Hassan A.; Denstedt, John D.

    2003-06-01

    Objectives: Symptomatic urolithiasis in pregnancy that does not respond to conservative measures has traditionally been managed with ureteral stent insertion or percutaneous nephrostomy (PCN). Holmium:yttrium-aluminum-garnet (YAG) laser lithotripsy using state-of-the-art ureteroscopes represents an emerging strategy for definitive stone management in pregnancy. The purpose of this study was to review the results of holmium laser lithotripsy in a cohort of patients who presented with symptomatic urolithiasis in pregnancy. Methods: A retrospective analysis was conducted at 2 tertiary stone centers from January 1996 to August 2001 to identify pregnant patients who were treated with ureteroscopic holmium laser lithotripsy for symptomatic urolithiasis or encrusted stents. Eight patients with a total of 10 symptomatic ureteral calculi and 2 encrusted ureteral stents were treated. Mean gestational age at presentation was 22 weeks. Mean stone size was 8.1 mm. Stones were located in the proximal ureter/ureteropelvic junction (UPJ) (3), mid ureter (1), and distal ureter (6). Results: Complete stone fragmentation and/or removal of encrusted ureteral stents were achieved in all patients using the holmium:YAG laser. The overall procedural success rate was 91%. The overall stone-free rate was 89%. No obstetrical or urological complications were encountered. Conclusions: Ureteroscopy and holmium laser lithotripsy can be performed safely in all stages of pregnancy providing definitive management of symptomatic ureteral calculi. The procedure can be done with minimal or no fluoroscopy and avoids the undesirable features of stents or nephrostomy tubes.

  13. Fragmentation process during Ho:YAG laser lithotripsy revealed by time-resolved imaging

    NASA Astrophysics Data System (ADS)

    Beghuin, Didier; Delacretaz, Guy P.; Schmidlin, Franz R.; Rink, Klaus

    1998-01-01

    The stone fragmentation process induced during Ho:YAG laser lithotripsy was observed by time-resolved flash video imaging. Possible acoustic transient occurrence was simultaneously monitored with a PVDF needle hydrophone. We used artificial and cystine kidney stones. We observed that, although the fragmentation process is accompanied with the formation of a cavitation bubble, cavitation has a minimal incidence on stone fragmentation. Fragment ejection is mainly due to a direct laser stone heating and vaporization of stone organic constituents and interstitial water. The minimal effect of the cavitation bubble for fragmentation is confirmed by acoustic transients measurements, which reveal weak pressure transients. This is in contrast with the fragmentation mechanisms induced by laser of shorter pulse duration.

  14. Detachable fiber optic tips for use in thulium fiber laser lithotripsy.

    PubMed

    Hutchens, Thomas C; Blackmon, Richard L; Irby, Pierce B; Fried, Nathaniel M

    2013-03-01

    The thulium fiber laser (TFL) has recently been proposed as an alternative to the Holmium:YAG (Ho:YAG) laser for lithotripsy. The TFL's Gaussian spatial beam profile provides higher power transmission through smaller optical fibers with reduced proximal fiber tip damage, and improved saline irrigation and flexibility through the ureteroscope. However, distal fiber tip damage may still occur during stone fragmentation, resulting in disposal of the entire fiber after the procedure. A novel design for a short, detachable, distal fiber tip that can fit into an ureteroscope's working channel is proposed. A prototype, twist-lock, spring-loaded mechanism was constructed using micromachining methods, mating a 150-μm-core trunk fiber to 300-μm-core fiber tip. Optical transmission measuring 80% was observed using a 30-mJ pulse energy and 500-μs pulse duration. Ex vivo human calcium oxalate monohydrate urinary stones were vaporized at an average rate of 187  μg/s using 20-Hz modulated, 50% duty cycle 5 pulse packets. The highest stone ablation rates corresponded to the highest fiber tip degradation, thus providing motivation for use of detachable and disposable distal fiber tips during lithotripsy. The 1-mm outer-diameter prototype also functioned comparable to previously tested tapered fiber tips.

  15. Endoscopic management of difficult common bile duct stones

    PubMed Central

    Trikudanathan, Guru; Navaneethan, Udayakumar; Parsi, Mansour A

    2013-01-01

    Endoscopy is widely accepted as the first treatment option in the management of bile duct stones. In this review we focus on the alternative endoscopic modalities for the management of difficult common bile duct stones. Most biliary stones can be removed with an extraction balloon, extraction basket or mechanical lithotripsy after endoscopic sphincterotomy. Endoscopic papillary balloon dilation with or without endoscopic sphincterotomy or mechanical lithotripsy has been shown to be effective for management of difficult to remove bile duct stones in selected patients. Ductal clearance can be safely achieved with peroral cholangioscopy guided laser or electrohydraulic lithotripsy in most cases where other endoscopic treatment modalities have failed. Biliary stenting may be an alternative treatment option for frail and elderly patients or those with serious co morbidities. PMID:23345939

  16. Compact laser illumination system for endoscopic interventions.

    PubMed

    Blase, Bastian

    2015-08-01

    External cold light sources as well as LEDs are commonly used for abdominal illumination in minimally invasive surgery. Still, both feature certain disadvantages. A new illumination system for endoscopes based on laser diodes is placed in the handle. No external light cables are needed. High conversion and coupling efficiencies and small package size allow for several diodes to be integrated, enabling color mixing and the adjustment of color temperatures. An optical module to collimate and combine the light is described. The heat to be dissipated is stored in a passive latent heat storage based on phase change materials surrounding the optical module. Thereby, operation time is considerably extended, as the handle's temperature is stabilized. To reduce the negative effect of coherent light on optical rough surfaces leading to patterns of spots, several devices for speckle reduction are developed and tested. By combining these components, an assembly of a powerful RGB laser light module for the integration in standard sized endoscopes is formed.

  17. Endoscopic laser stereotaxis: management of brain lesions

    NASA Astrophysics Data System (ADS)

    Zamorano, Lucia J.; Chavantes, Maria C.; Moure, Federico; Diaz, Fernando

    1994-05-01

    Image-guided stereotaxis is an accurate and safe method of directing therapy to target volumes defined in 2D multi-planes or 3D perspectives using computer reconstruction of image data. The major limitations of stereotactic techniques are the lack of intraoperative visualization and the ability to directly monitor the procedures, and changes of intracranial coordinates after decompression of cystic lesions or aspiration of cerebrospinal fluid in the management of intraventricular lesions. Stereotactic neuroendoscopy involves integration of rigid-flexible endoscopy and the Nd-YAG laser in 2D/3D multiplanar image-guided stereotactic procedures. The major advantages of endoscopic laser surgery include being minimally invasive (burrhole or small craniotomy surgery), direct intraoperative visualization, hemostasis, evacuation or resection assessment, and wide exploration of intracranial cavities or ventricles. We used endoscopic laser surgery in the management of 202 patients undergoing biopsy, aspiration, resection, and internal decompression of deep and subcortical intracranial lesions, and for different types of fenestration procedures. Image-guidance combined with endoscopic techniques may offer a safe, accurate alternative to conventional neurosurgical procedures in treating small solid, cystic, intraventricular lesions, and in fenestration procedures.

  18. Investigation on the impact of pulse duration for laser induced lithotripsy

    NASA Astrophysics Data System (ADS)

    Sroka, Ronald; Kiris, Tugba; Fiedler, Sebastian; Scheib, Gabriel; Kuznetsova, Julia; Pongratz, Thomas

    2014-03-01

    Objective: In-vitro investigation of Ho:YAG-laser induced stone fragmentation was performed to identify potential impacts of different pulse durations on stone fragmentation characteristics. Materials and Methods: An innovative Ho:YAG laser system (Swiss LaserClast, EMS S.A., Nyon, Switzerland) with selectable long- or short pulse mode was tested with regard to its fragmentation properties. The pulse duration depends on the specific laser parameter used. Fragmentation tests (hand held, hands free, single pulse induced crater) on artificial BEGO-Stones and fiber burn back tests were performed under reproducible experimental conditions. Additionally, the repulsion of long versus short laser pulses was compared using the pendulum set-up. Results: Differences in fragmentation rates between the two pulse duration regimes were seen. The difference was, however, not statistically significant. Using long pulse mode, the fiber burn back is nearly negligible while in short pulse mode an increased burn back was seen. The results of the pendulum test showed that the deviation induced by the momentum of shorter pulses is increased compared to longer pulses. Conclusion: Long pulse-mode showed reduced side effects like repulsion and fiber burn back in comparison to short pulse-mode while fragmentation rates remained at a comparable level. Lower push back and reduced burn back of longer laser pulses may results in better clinical outcome of laser lithotripsy and more convenient handling during clinical use.

  19. Ureteroscopy and holmium: YAG laser lithotripsy as emergency treatment for acute renal failure caused by impacted ureteral calculi.

    PubMed

    Jiang, Haowen; Wu, Zhong; Ding, Qiang

    2008-09-01

    To present our clinical outcomes in managing acute renal failure caused by impacted ureteral calculi with ureteroscopy and holmium: yttrium-aluminum-garnet laser lithotripsy as emergency treatment. A series of 27 patients with acute postrenal failure were treated from November 2002 to December 2005. Impacted calculi were located in bilateral ureters in 22 patients and unilateral ureters in 5 patients with a solitary or single functioning kidney. Acute renal failure was demonstrated with oliguria or anuria and a significant increase in serum creatinine and blood urea nitrogen. Patients were treated emergently with ureteroscopy and holmium:yttrium-aluminum-garnet laser lithotripsy in the hospital within 24 hours. Ureteral stenting was performed in all cases. Postoperative renal function, electrolytes, and urine volume were monitored daily for 7 days. Radiography and/or ultrasonography were performed at a follow-up visit in 4 weeks. Ureteroscopy and laser lithotripsy were successfully performed in all patients. The mean operative time was 29.2 minutes (range 15-60). The successful fragmentation rate in the ureteroscopic procedure was 93.9% (46 of 49), and the overall stone-free rate was 88.9% (24 of 27). Shock wave lithotripsy was used in 3 patients after recovery of renal function. Of the 27 patients, 26 (96.3%) returned to normal renal function within 7 days. One patient (3.7%) had significant improvement of renal function, but it had not returned to normal at 12 weeks of follow-up. No intraoperative complications or postoperative ureteral stricture occurred. Emergency ureteroscopy and holmium: yttrium-aluminum-garnet laser lithotripsy can be safely and successfully performed by skilled endourologists for acute renal failure caused by impacted ureteral calculi.

  20. Impact of pulse duration on Ho:YAG laser lithotripsy: fragmentation and dusting performance.

    PubMed

    Bader, Markus J; Pongratz, Thomas; Khoder, Wael; Stief, Christian G; Herrmann, Thomas; Nagele, Udo; Sroka, Ronald

    2015-04-01

    In vitro investigations of Ho:YAG laser-induced stone fragmentation were performed to identify potential impacts of different pulse durations on stone fragmentation characteristics. A Ho:YAG laser system (Swiss LaserClast, EMS S.A., Nyon, Switzerland) with selectable long or short pulse mode was tested with regard to its fragmentation and laser hardware compatibility properties. The pulse duration is depending on the specific laser parameters. Fragmentation tests (hand-held, hands-free, single-pulse-induced crater) on artificial BEGO stones were performed under reproducible experimental conditions (fibre sizes: 365 and 200 µm; laser settings: 10 W through combinations of 0.5, 1, 2 J/pulse and 20, 10, 5 Hz, respectively). Differences in fragmentation rates between the two pulse duration regimes were detected with statistical significance for defined settings. Hand-held and motivated Ho:YAG laser-assisted fragmentation of BEGO stones showed no significant difference between short pulse mode and long pulse mode, neither in fragmentation rates nor in number of fragments and fragment sizes. Similarly, the results of the hands-free fragmentation tests (with and without anti-repulsion device) showed no statistical differences between long pulse and short pulse modes. The study showed that fragmentation rates for long and short pulse durations at identical power settings remain at a comparable level. Longer holmium laser pulse duration reduces stone pushback. Therefore, longer laser pulses may result in better clinical outcome of laser lithotripsy and more convenient handling during clinical use without compromising fragmentation effectiveness.

  1. Use of holmium laser in conjunction with electrohydraulic lithotripsy in the treatment of bladder calculi

    NASA Astrophysics Data System (ADS)

    Terranova, Steven A.; Despradel, Vidal M.; Mian, Badar M.; Averch, Timothy D.

    2001-05-01

    Drawbacks to the treatment of bladder calculi demolition include excessive mucosal trauma and bleeding with the use of the electrohydraulic lithotripsy (EHL) and prolonged operating room times with the low wattage holmium laser (HOL). The outcome of bladder stones treated by combining the use of HOL and the EHL is reported. Via the cystoscope, the bladder stones were identified in five male patients and the HOL was used to bore to the center of each stone. The EHL probe was then inserted into each borehole and was used to fragment the stones into pieces which could be removed with an Ellik evacuator. All the stones were fragmented to pieces, which were removed without difficulty. Upon completion, minimal mucosal trauma and stone dust were visualized. No complications were observed.

  2. Flexible ureteroscopic laser lithotripsy for upper urinary tract stone disease in patients with spinal cord injury.

    PubMed

    Tepeler, Abdulkadir; Sninsky, Brian C; Nakada, Stephen Y

    2015-11-01

    The objective of this study is to present the outcomes of flexible ureteroscopic laser lithotripsy (URS) for upper urinary tract stone disease in spinal cord injury (SCI) patients performed by a single surgeon. A retrospective analysis was performed for SCI patients treated with flexible URS for proximal ureter and kidney stone disease by a single surgeon between 2003 and 2013. Patient characteristics, operative outcomes, metabolic evaluation, and stone analyses were assessed in detail. A total of 27 URS procedures were performed for urolithiasis in 21 renal units of 19 patients. The mean age was 52.1 ± 15.6 years (16-72) and mean BMI was 29.2 ± 7.3 kg/m(2) (20-45.7). Etiology of SCI was trauma (n: 10), multiple sclerosis (n: 6), cerebrovascular accident (n: 1), or undetermined (n: 2). The mean stone size was 15.9 ± 8.6 (6-40) mm. In the 27 URS procedures, stones were located in the ureter (n: 5), the kidney (n: 14), and both areas (n: 8). Mean hospitalization time was 2.0 ± 2.4 (0-10) days. Postoperative complications were observed in 6 cases (22.2%). Three major complications included urosepsis (n: 1) and respiratory failure (n: 2), that were observed postoperatively and required admission to the intensive care unit. The 2 minor complications were hypotension, fever and UTI, and required medical treatment. Fourteen (66.6%) of the 21 renal units were stone free. Calcium phosphate carbonate (n: 9) and struvite (n: 5) were the primary stone compositions detected. Hypocitraturia (n: 6), hypercalciuria (n: 5), hypernaturia (n: 5), hyperoxaluria (n: 4), and hyperuricosuria (n: 1) were common abnormalities in 24-h urine analysis. Ureteroscopic laser lithotripsy can be an effective treatment modality for SCI patients with upper urinary tract calculi.

  3. Alternative infrared lasers for endoscopic surgery

    NASA Astrophysics Data System (ADS)

    Bass, Lawrence S.; Font, David E.; Oz, Mehmet C.; Trokel, Stephen L.; Treat, Michael R.

    1990-06-01

    There are substantial technical problems attendant to the removal of sessile polyps from the lumen of thin walled gastrointestinal organs such as the colon. A laser system which is capable of precise and circumscribed mucosal tissue vaporization would be useful for this task. Because of technical shortcomings of existing medical laser systems, we investigated the possibilities of mid-infrared lasers which could take advantage of large water absorption peaks in the 2 micron region to produce precise vaporization while retaining fiberoptic transmissibility. In addition to a high absorption wavelength, pulsed energy delivery contributes to precise vaporizing capabilities. The laser system that best fits our criteria is the 2.15 micron thulium-holmium- chromium:YAG which produces 200 microsecond pulses of energies up to 1 joule at firing rates up to 6 Hz. The laser output is transmitted efficiently via low hydroxyl quartz fibers. Ablative efficiency, defined here as the slope of the vaporization depth versus energy, reveals that the THC:YAG produces approximately 3 times greater depth of vaporization per joule than the cw Nd:YAG. On average, the Nd:YAG produced 1.5 times the amount of thermal damage as the THC:YAG for a given depth of vaporization. The THC:YAG laser should have an important clinical role since its use could reduce the risk of perforation in endoscopic laser procedures such as the removal of sessile polyps.

  4. [Holmium: yttrium-aluminum-garnet (Ho: YAG) laser lithotripsy in the treatment of broncholithiasis].

    PubMed

    Cheng, Y; Zhang, W; Zhang, H; Liu, Y; Li, N; Cao, J; Wang, G F

    2017-01-12

    Objective: To assess the effectiveness of Ho: YAG Laser in the treatment of broncholithiasis. Methods: We retrospectively reviewed the clinical data of 6 patients who underwent Ho: YAG Laser lithotripsy in Peking University First Hospital during May 2012 to October 2015. 4 females and 2 males, with a median age of 60 years, were enrolled. Among 6 patients, persistent cough(n=2), hemoptysis(n=2), recurrent pneumonia(n=2) were the main clinical symptoms. Broncholiths were found in the left side in 1 patient and right side in 5 patients. 2 broncholiths were located in main bronchus and 4 in segmental bronchus. There were 2 patients with intraluminal broncholiths and 4 with transbranchial broncholiths. All 6 patients received Ho: YAG Laser(0.8-1.2 J pulse energies, 5-10 Hz frequencies, 365 μm laser fibers) under rigid bronchoscopy in general anesthesia and experienced relief of symptoms. Results: Complete removal of broncholith was accomplished in intraluminal broncholith group and 1 patient in transbracnhial broncholith group, the other 3 transbracnhial broncholiths were partly removed. Complications included perioperative massive hemolysis(n=1), bronchoesophageal fistula(n=1) and postoperative pneumonia (n=2), no long term complications were encounted. Conclusion: The Ho: YAG were associated with acute complications including fistula, perioperative massive hemolysis, infections and no long-term side effects. It represents a safe and effective therapy option for broncholithiasis.

  5. Combined cataract and glaucoma surgery: trabeculectomy versus endoscopic laser cycloablation.

    PubMed

    Gayton, J L; Van Der Karr, M; Sanders, V

    1999-09-01

    To determine whether combined cataract surgery with endoscopic laser cycloablation produces less inflammation than cataract surgery combined with a filtering procedure. Taylor Regional Hospital (surgeries) and EyeSight Associates (examinations), Warner Robins, Georgia, USA. A randomized prospective study was conducted of 58 eyes of 58 patients comparing endoscopic laser cycloablation performed through a cataract incision at the time of cataract surgery with combined trabeculectomy and cataract surgery. Mean follow-up was 2 years. At the final available visit, 30% of endoscopic laser patients achieved intraocular pressure control (below 19 mm Hg) without medication and 65% with medication. Forty percent of trabeculectomy patients achieved control without medication and 52% with medication. Four endoscopic laser patients (14%) and 3 trabeculectomy patients (10%) were considered treatment failures (required additional surgical intervention). Endoscopic laser cycloablation performed through a cataract incision was a reasonably safe and effective alternative to combined cataract and trabeculectomy surgery, providing an option for cataract patients who have glaucoma requiring surgical intervention.

  6. In vitro investigations of repulsion during laser lithotripsy using a pendulum set-up.

    PubMed

    Sroka, Ronald; Haseke, Nicolas; Pongratz, Thomas; Hecht, Volkmar; Tilki, Derya; Stief, Christian G; Bader, Markus Jürgen

    2012-05-01

    Ureteroscopic laser lithotripsy is a commonly used technique to treat ureteral calculi.The type of energy source used is one of the main influences of retrograd calculi propulsion. Using a momentum pendulum under-water set-up the induced momentum and the initial velocity were investigated. Pulsed laser light from three different clinically available laser systems, including a Ho:YAG laser, a frequency-doubled double-pulse (second harmonic generation, SHG) Nd:YAG laser and a flash-lamp pumped dye (FLPD) laser, were transmitted via flexible fibres of different core diameter to the front of the pendulum sinker. Single pulses at variable pulse energy, according to the clinical laser parameter settings, were applied to the target sinker, thus causing a repulsion-induced deflection which was documented by video recording. The maximum deflection was determined. Solving the differential equation of a pendulum gives the initial velocity, the laser-induced momentum and the efficiency of momentum transfer. The induced deflection as well as the starting velocity of the two short-duration pulsed laser systems (SHG Nd:YAG, FLPD) were similar (s (max) = 2-3.6 cm and v (0) = 150-200 mm/s, respectively), whereas both values were lower using the Ho:YAG laser with a long pulse duration (s (max) = 0.9--1.6 cm and v (0) = 60-105 mm/s, respectively). The momentum I induced by the Ho:YAG laser was only 50% and its transfer efficacy η (Repuls) was reduced to less than 5% of the values of the two short-pulsed laser systems. This investigation clearly showed the variable parts and amounts of repulsion using different pulsed lasers in an objective and reproducible manner. The momentum transfer efficiency could be determined without any physical friction problems. Further investigations are needed to compare stone fragmentation techniques with respect to laser repulsion and its clinical impact.

  7. Integrated Multipoint-Laser Endoscopic Airway Measurements by Transoral Approach

    PubMed Central

    Neitsch, Marie; Horn, Iris-Susanne; Hofer, Mathias; Dietz, Andreas; Fischer, Miloš

    2016-01-01

    Objectives. Optical and technical characteristics usually do not allow objective endoscopic distance measurements. So far no standardized method for endoscopic distance measurement is available. The aim of this study was to evaluate the feasibility and accuracy of transoral airway measurements with a multipoint-laser endoscope. Methods. The semirigid endoscope includes a multipoint laser measurement system that projects 49 laser points (wavelength 639 nm, power < 5 mW) into the optical axis of the endoscopic view. Distances, areas, and depths can be measured in real-time. Transoral endoscopic airway measurements were performed on nine human cadavers, which were correlated with CT measurements. Results. The preliminary experiment showed an optimum distance between the endoscope tip and the object of 5 to 6 cm. There was a mean measurement error of 3.26% ± 2.53%. A Spearman correlation coefficient of 0.95 (p = 0.01) was calculated for the laryngeal measurements and of 0.93 (p < 0.01) for the tracheal measurements compared to the CT. Using the Bland-Altman-Plot, the 95% limits of agreement for the laryngeal measurements were satisfactory: −0.76 and 0.93. Conclusions. Integrated multipoint-laser endoscopic measurement is a promising technical supplement, with potential use in diagnostic endoscopy and transoral endoscopic surgery in daily practice. PMID:27022612

  8. Ureteroscopy and holmium laser lithotripsy: is this procedure safe in pregnant women with ureteral stones at different locations?

    PubMed

    Adanur, Senol; Ziypak, Tevfik; Bedir, Fevzi; Yapanoglu, Turgut; Aydın, Hasan Riza; Yılmaz, Mehmet; Aksoy, Mehmet; Ozbey, Isa

    2014-06-30

    The aim of this study was to assess the safety and effectiveness of ureteroscopy and Holmium: Yttrium-Aluminum-Garnet lithotripsy for the treatment of ureteral stones with different localizations in symptomatic pregnant women. A retrospective analysis was performed on 19 pregnant patients referred to our center between January 2005 and December 2012 with symptomatic hydronephrosis requiring surgical intervention. 7.5 F and 9.5 F semirigid ureterorenoscopy with Holmium laser lithotripsy was used for treatment in all patients. Complications were stratified according to modified Clavien criteria. The mean age of patients was 25.4 (18-41) years, and the mean gestation duration was 24.8 (7-33) weeks. Six cases (31.5%) had a history of stone. Solitary kidney secondary to previous nephrectomy was observed in 2 patients and 1 patient had a hypoplastic kidney. Abdominal ultrasonography was used as the main diagnostic tool. Mean stone size was 9.2 mm (6-13). The location of the stones was the lower, middle, and upper ureter in 8 (42.1%), 5 (26.3%) and 6 (31.5%) cases, respectively. All stones were fragmented with Holmium laser lithotripsy. Of the 19 patients, 11 (57.8%) required double J stent insertion peroperatively. Intraoperative urological and obstetric complications were not observed. Postoperatively two complications were noted. According to Clavien criteria a complication was level 1, and the other was level 2. For treatment of pregnant women with symptomatic ureteral stones in every location, Holmium laser lithotripsy with a semirigid ureteroscopy can be used as judicious treatment. This approach is effective and safe with an acceptable complication rate.

  9. Collateral damage to the ureter and Nitinol stone baskets during thulium fiber laser lithotripsy.

    PubMed

    Wilson, Christopher R; Hardy, Luke A; Irby, Pierce B; Fried, Nathaniel M

    2015-07-01

    The experimental Thulium fiber laser (TFL) is currently being studied as a potential alternative lithotripter to the clinical gold standard Holmium:YAG laser. Safety studies characterizing undesirable Holmium:YAG laser-induced damage to ureter tissue and stone baskets have been previously reported. Similarly, this study characterizes TFL induced ureter and stone basket damage. A TFL beam with energy of 35 mJ per pulse, pulse duration of 500 µs, and variable pulse rates of 50-500 Hz, was delivered through 100-µm-core optical fibers, to either porcine ureter wall, in vitro, or a standard 1.9-Fr Nitinol stone basket wire. Ureter perforation times were measured and gross, histological, and optical coherence tomography images of the ablation area were acquired. Stone basket damage was graded as a function of pulse rate, number of pulses, and working distance. TFL operation at 150, 300, and 500 Hz produced mean ureter perforation times of 7.9, 3.8, and 1.8 seconds, respectively. Collateral damage widths averaged 510, 370, and 310 µm. Nitinol wire damage decreased with working distance and was non-existent at distances greater than 1.0 mm. In contact mode, 500 pulses delivered at pulse rates ≥300 Hz (≤1.5 seconds) were sufficient to cut Nitinol wires. The TFL, operated in low pulse energy and high pulse rate mode, may provide a greater safety margin than the standard Holmium:YAG laser for lithotripsy, as evidenced by longer TFL ureter perforation times and shorter non-contact working distances for stone basket damage than previously reported with Holmium:YAG laser. © 2015 Wiley Periodicals, Inc.

  10. Holmium:YAG (lambda = 2,120 nm) versus thulium fiber (lambda = 1,908 nm) laser lithotripsy.

    PubMed

    Blackmon, Richard L; Irby, Pierce B; Fried, Nathaniel M

    2010-03-01

    The holmium:YAG laser is currently the most common laser lithotripter. However, recent experimental studies have demonstrated that the thulium fiber laser is also capable of vaporizing urinary stones. The high-temperature water absorption coefficient for the thulium wavelength (mu(a) = 160 cm(-1) at lambda = 1,908 nm) is significantly higher than for the holmium wavelength (mu(a) = 28 cm(-1) at lambda = 2,120 nm). We hypothesize that this should translate into more efficient laser lithotripsy using the thulium fiber laser. This study directly compares stone vaporization rates for holmium and thulium fiber lasers. Holmium laser radiation pulsed at 3 Hz with 70 mJ pulse energy and 220 microseconds pulse duration was delivered through a 100-microm-core silica fiber to human uric acid (UA) and calcium oxalate monohydrate (COM) stones, ex vivo (n = 10 each). Thulium fiber laser radiation pulsed at 10 Hz with 70 mJ pulse energy and 1-millisecond pulse duration was also delivered through a 100-microm fiber for the same sets of 10 stones each. For the same number of pulses and total energy (126 J) delivered to each stone, the mass loss averaged 2.4+/-0.6 mg (UA) and 0.7+/-0.2 mg (COM) for the holmium laser and 12.6+/-2.5 mg (UA) and 6.8+/-1.7 (COM) for the thulium fiber laser. UA and COM stone vaporization rates for the thulium fiber laser averaged 5-10 times higher than for the holmium laser at 70 mJ pulse energies. With further development, the thulium fiber laser may represent an alternative to the conventional holmium laser for more efficient laser lithotripsy.

  11. Endoscopic laser incision of the prostate

    NASA Astrophysics Data System (ADS)

    Gilbert, Peter T. O.

    1998-07-01

    To reduce morbidity and costs of transurethral incision of the prostate in cases with bladder neck obstruction and insignificant prostatic hyperplasia, a Nd:YAG laser, wavelength 1064 nm, was used for endoscopic tissue vaporization. Twenty seven patients suffering from severe urinary obstructive symptoms due to a high-riding vesical neck, were operated on under general anesthesia. Under endoscopic control and by means of a 600 micrometer lateral- firing quartz fiber two incisions were performed, starring at the 7 o'clock and 5 o'clock position, respectively, of the bladder neck and following the floor of the prostatic urethra to either side of the verumontanum. Vaporization was achieved with the fiber in permanent tissue contact and the laser working at 60 W power in continuous mode. Total energy averaged 10,000 J. No catheter was inserted and all patients were discharged on the same day after the first micturition. Anti-inflammatory agents were administered for two weeks. No serious complications were encountered postoperatively. Results were evaluated by means of clinical examination, uroflowmetry, sonographic measurement of residual urine and the International Prostate Symptom Score (IPSS) questionnaire. Considering a mean follow up of 15 months, all patients experienced considerable improvement of their obstruction, their urinary peak flow averaging 21 ml/s and their IPSS score 6.7 (preoperatively 12.2 ml/s and 21.8, respectively). As compared to the Collings knife, laser-incision of the prostate carries no risk of bleeding, thus obviating the need of catheterization. It can safely be done in an outpatient setting, probably as well under local as under general anesthesia.

  12. Efficacy and safety of Ho:YAG Laser Lithotripsy for ureteroscopic removal of proximal and distal ureteral calculi

    PubMed Central

    2014-01-01

    Background Laser lithotripsy is an established endourological modality. Ho:YAG laser have broadened the indications for ureteroscopic stone managements to include larger stone sizes throughout the whole upper urinary tract. Aim of current work is to assess efficacy and safety of Ho:YAG laser lithotripsy during retrograde ureteroscopic management of ureteral calculi in different locations. Methods 88 patients were treated with ureteroscopic Ho:YAG laser lithotripsy in our institute. Study endpoint was the number of treatments until the patient was stone-free. Patients were classified according to the location of their stones as Group I (distal ureteric stones, 51 patients) and group II (proximal ureteral stones, 37). Group I patients have larger stones as Group II (10.70 mm vs. 8.24 mm, respectively, P = 0.020). Results Overall stone free rate for both groups was 95.8%. The mean number of procedures for proximal calculi was 1.1 ± 0.1 (1–3) and for distal calculi was 1.0 ± 0.0. The initial treatment was more successful in patients with distal ureteral calculi (100% vs. 82.40%, respectively, P = 0.008). No significant difference in the stone free rate was noticed after the second laser procedure for stones smaller versus larger than 10 mm (100% versus 94.1%, P = 0.13). Overall complication rate was 7.9% (Clavien II und IIIb). Overall and grade-adjusted complication rates were not dependant on the stone location. No laser induced complications were noticed. Conclusions The use of the Ho:YAG laser appears to be an adequate tool to disintegrate ureteral calculi independent of primary location. Combination of the semirigid and flexible ureteroscopes as well as the appropriate endourologic tools could likely improve the stone clearance rates for proximal calculi regardless of stone-size. PMID:25107528

  13. Efficacy and safety of Ho:YAG laser lithotripsy for ureteroscopic removal of proximal and distal ureteral calculi.

    PubMed

    Khoder, Wael Y; Bader, Markus; Sroka, Ronald; Stief, Christian; Waidelich, Raphaela

    2014-08-08

    Laser lithotripsy is an established endourological modality. Ho:YAG laser have broadened the indications for ureteroscopic stone managements to include larger stone sizes throughout the whole upper urinary tract. Aim of current work is to assess efficacy and safety of Ho:YAG laser lithotripsy during retrograde ureteroscopic management of ureteral calculi in different locations. 88 patients were treated with ureteroscopic Ho:YAG laser lithotripsy in our institute. Study endpoint was the number of treatments until the patient was stone-free. Patients were classified according to the location of their stones as Group I (distal ureteric stones, 51 patients) and group II (proximal ureteral stones, 37). Group I patients have larger stones as Group II (10.70 mm vs. 8.24 mm, respectively, P = 0.020). Overall stone free rate for both groups was 95.8%. The mean number of procedures for proximal calculi was 1.1 ± 0.1 (1-3) and for distal calculi was 1.0 ± 0.0. The initial treatment was more successful in patients with distal ureteral calculi (100% vs. 82.40%, respectively, P = 0.008). No significant difference in the stone free rate was noticed after the second laser procedure for stones smaller versus larger than 10 mm (100% versus 94.1%, P = 0.13). Overall complication rate was 7.9% (Clavien II und IIIb). Overall and grade-adjusted complication rates were not dependent on the stone location. No laser induced complications were noticed. The use of the Ho:YAG laser appears to be an adequate tool to disintegrate ureteral calculi independent of primary location. Combination of the semirigid and flexible ureteroscopes as well as the appropriate endourologic tools could likely improve the stone clearance rates for proximal calculi regardless of stone-size.

  14. Hollow steel tips for reducing distal fiber burn-back during thulium fiber laser lithotripsy.

    PubMed

    Hutchens, Thomas C; Blackmon, Richard L; Irby, Pierce B; Fried, Nathaniel M

    2013-07-01

    The use of thulium fiber laser (TFL) as a potential alternative laser lithotripter to the clinical holmium:YAG laser is being studied. The TFL's Gaussian spatial beam profile provides efficient coupling of higher laser power into smaller core fibers without proximal fiber tip degradation. Smaller fiber diameters are more desirable, because they free up space in the single working channel of the ureteroscope for increased saline irrigation rates and allow maximum ureteroscope deflection. However, distal fiber tip degradation and "burn-back" increase as fiber diameter decreases due to both excessive temperatures and mechanical stress experienced during stone ablation. To eliminate fiber tip burn-back, the distal tip of a 150-μm core silica fiber was glued inside 1-cm-long steel tubing with fiber tip recessed 100, 250, 500, 1000, or 2000 μm inside the steel tubing to create the hollow-tip fiber. TFL pulse energy of 34 mJ with 500-μs pulse duration and 150-Hz pulse rate was delivered through the hollow-tip fibers in contact with human calcium oxalate monohydrate urinary stones during ex vivo studies. Significant fiber tip burn-back and degradation was observed for bare 150-μm core-diameter fibers. However, hollow steel tip fibers experienced minimal fiber burn-back without compromising stone ablation rates. A simple, robust, compact, and inexpensive hollow fiber tip design was characterized for minimizing distal fiber burn-back during the TFL lithotripsy. Although an increase in stone retropulsion was observed, potential integration of the hollow fiber tip into a stone basket may provide rapid stone vaporization, while minimizing retropulsion.

  15. Endoscopic laser palliation for advanced malignant dysphagia.

    PubMed Central

    Bown, S G; Hawes, R; Matthewson, K; Swain, C P; Barr, H; Boulos, P B; Clark, C G

    1987-01-01

    Palliative treatment of malignant dysphagia aims to optimise swallowing for the maximum time possible with the minimum of general distress to these seriously ill patients. Thirty four patients considered unsuitable for surgery because of advanced malignancy, other major pathology or in whom previous surgery had been unsuccessful were treated endoscopically with the Nd YAG laser. Significant improvement was achieved in 29 (85%). On a scale of 0-4 (0 = normal swallowing; 4 = dysphagia for all fluids), mean improvement was 1.7, with 25 patients (74%) able to swallow most, or all solids after treatment. With increasing experience, the average number of treatment sessions required for each patient became less; initial time in hospital became comparable to that needed for intubation. Failures were caused by inappropriate patient selection (3), or laser related perforation (2). The mean survival in the whole group was 19 weeks (range 2-44). Eighteen patients needed further treatment for recurrent dysphagia, a mean of six weeks (range 2-15) after initial therapy. Ten of these responded, but eight eventually required insertion of a prosthetic tube. The duration of good palliation was very variable after initial laser therapy. Images Fig. 3 PMID:2443431

  16. An integrated fiber and stone basket device for use in Thulium fiber laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Wilson, Christopher R.; Hutchens, Thomas C.; Hardy, Luke A.; Irby, Pierce B.; Fried, Nathaniel M.

    2014-03-01

    The Thulium fiber laser (TFL) is being explored as an alternative laser lithotripter to the Holmium:YAG laser. The TFL's superior near-single mode beam profile enables higher power transmission through smaller fibers with reduced proximal fiber tip damage. Recent studies have also reported that attaching hollow steel tubing to the distal fiber tip decreases fiber degradation and burn-back without compromising stone ablation rates. However, significant stone retropulsion was observed, which increased with pulse rate. In this study, the hollow steel tip fiber design was integrated with a stone basket to minimize stone retropulsion during ablation. A device was constructed consisting of a 100-μm-core, 140-μm-OD silica fiber outfitted with 5-mm-long stainless steel tubing at the distal tip, and integrated with a 1.3-Fr (0.433-mm-OD) disposable nitinol wire basket, to form an overall 1.9-Fr (0.633-mm- OD) integrated device. This compact design may provide several potential advantages including increased flexibility, higher saline irrigation rates through the ureteroscope working channel, and reduced fiber tip degradation compared to separate fiber and stone basket manipulation. TFL pulse energy of 31.5 mJ with 500 μs pulse duration and pulse rate of 500 Hz was delivered through the integrated fiber/basket device in contact with human uric acid stones, ex vivo. TFL stone ablation rates measured 1.5 +/- 0.2 mg/s, comparable to 1.7 +/- 0.3 mg/s (P > 0.05) using standard bare fiber tips separately with a stone basket. With further development, this device may be useful for minimizing stone retropulsion, thus enabling more efficient TFL lithotripsy at higher pulse rates.

  17. Large subcapsular hematoma following ureteroscopic laser lithotripsy of renal calculi in a spina bifida patient: lessons we learn

    PubMed Central

    Vaidyanathan, Subramanian; Samsudin, Azi; Singh, Gurpreet; Hughes, Peter L; Soni, Bakul M; Selmi, Fahed

    2016-01-01

    Introduction Paraplegic patients are at greater risk of developing complications following ureteroscopic lithotripsy because of urine infection associated with neuropathic bladder, difficulties in access due to altered anatomy of urinary bladder and urethra, spinal curvature, spasticity, and contractures. We report the occurrence of large subcapsular hematoma following ureteroscopy and discuss lessons we learn from this case. Case report A 48-year-old male patient with spina bifida underwent ureteroscopy with laser lithotripsy and ureteric stenting for left ureteric stone and staghorn calculus with hydronephrosis; laser lithotripsy was repeated after 3 months; both procedures were performed by a senior urologist and did not result in any complications. Ureteroscopic laser lithotripsy was performed 5 months later by a urological trainee; it was difficult to negotiate the scope as vision became poor because of bleeding (as a result of the procedure). Postoperatively, hematuria persisted; temperature was 39°C. Cefuroxime was given intravenously followed by gentamicin for 5 days; hematuria subsided gradually; he was discharged home. Ten days later, this patient developed temperature, the urine culture grew Pseudomonas aeruginosa, and ciprofloxacin was given orally. Computed tomography (CT) of the urinary tract, performed 4 weeks after ureteroscopy, revealed a 9×7 cm subcapsular collection on the left kidney compressing underlying parenchyma. Percutaneous drainage was not feasible because of severe curvature of spine. Isotope renogram revealed deterioration in left renal function from 30% to 17%. Follow-up CT revealed reduction in the size of subcapsular hematoma, no hydronephrosis, and several residual calculi. Conclusion Risk of subcapsular hematoma following ureteroscopic lithotripsy can be reduced by avoiding prolonged endoscopy and performing ureteroscopy under low pressure. When a paraplegic patient develops features of infection after ureteroscopy, renal

  18. Large subcapsular hematoma following ureteroscopic laser lithotripsy of renal calculi in a spina bifida patient: lessons we learn.

    PubMed

    Vaidyanathan, Subramanian; Samsudin, Azi; Singh, Gurpreet; Hughes, Peter L; Soni, Bakul M; Selmi, Fahed

    2016-01-01

    Paraplegic patients are at greater risk of developing complications following ureteroscopic lithotripsy because of urine infection associated with neuropathic bladder, difficulties in access due to altered anatomy of urinary bladder and urethra, spinal curvature, spasticity, and contractures. We report the occurrence of large subcapsular hematoma following ureteroscopy and discuss lessons we learn from this case. A 48-year-old male patient with spina bifida underwent ureteroscopy with laser lithotripsy and ureteric stenting for left ureteric stone and staghorn calculus with hydronephrosis; laser lithotripsy was repeated after 3 months; both procedures were performed by a senior urologist and did not result in any complications. Ureteroscopic laser lithotripsy was performed 5 months later by a urological trainee; it was difficult to negotiate the scope as vision became poor because of bleeding (as a result of the procedure). Postoperatively, hematuria persisted; temperature was 39°C. Cefuroxime was given intravenously followed by gentamicin for 5 days; hematuria subsided gradually; he was discharged home. Ten days later, this patient developed temperature, the urine culture grew Pseudomonas aeruginosa, and ciprofloxacin was given orally. Computed tomography (CT) of the urinary tract, performed 4 weeks after ureteroscopy, revealed a 9×7 cm subcapsular collection on the left kidney compressing underlying parenchyma. Percutaneous drainage was not feasible because of severe curvature of spine. Isotope renogram revealed deterioration in left renal function from 30% to 17%. Follow-up CT revealed reduction in the size of subcapsular hematoma, no hydronephrosis, and several residual calculi. Risk of subcapsular hematoma following ureteroscopic lithotripsy can be reduced by avoiding prolonged endoscopy and performing ureteroscopy under low pressure. When a paraplegic patient develops features of infection after ureteroscopy, renal imaging should be carried out promptly

  19. Transurethral lithotripsy with holmium-YAG laser of a large exogenous prostatic calculus.

    PubMed

    Hasegawa, Masanori; Ohara, Rei; Kanao, Kent; Nakajima, Yosuke

    2011-04-01

    Prostatic calculi are classified into two types, endogenous and exogenous calculi, based on their origin. Endogenous calculi are commonly observed in elderly men; however, exogenous prostatic calculi are extremely rare. We report here the case of a 51-year-old man who suffered incontinence and pollakiuria with a giant exogenous prostatic calculus almost completely replacing the prostatic tissue. X-rays and computed tomography demonstrated a large calculus of 65 × 58 mm in the small pelvic cavity. The patient underwent a transurethral lithotripsy with a holmium-YAG laser and a total of 85 g of disintegrated stones was retrieved and chemical stone analysis revealed the presence of magnesium ammonium phosphate. The incontinence improved and the voiding volume increased dramatically, and no stone recurrence in the prostatic fossa occurred at the 2 years follow-up. The etiology of this stone formation seemed to be based on some exogenous pathways combined with urinary stasis and chronic urinary infection due to compression fracture of the lumbar vertebra.

  20. Comparison between extracorporeal shock wave lithotripsy and semirigid ureterorenoscope with holmium:YAG laser lithotripsy for treating large proximal ureteral stones.

    PubMed

    Wu, Ching-Fang; Shee, Jia-Jen; Lin, Wei-Yu; Lin, Chun-Liang; Chen, Chih-Shou

    2004-11-01

    Management of large impacted upper ureteral calculi remains challenging for urologists. These calculi are frequently associated with obstructive uropathy and deteriorated renal function. Extracorporeal shock wave lithotripsy (SWL) is the least invasive treatment but its success rate is decreased for large impacted upper ureteral calculi. According to the American Urological Association guidelines on ureteral stones published in 1997, the appropriateness of ureteroscopy decreases when stone size exceeds 1 cm. However, the application of advanced ureteroscopy and techniques has increased the success rate of treating proximal ureter calculi. In this study we compared the safety and efficacy of ureterorenoscopic holmium:YAG laser lithotripsy (URSL) with SWL for large impacted proximal ureteral stones. This study evaluated 82 patients with large impacted upper ureteral stones. Two patients were excluded from study owing to conversion to open surgery. SWL and URSL were performed in 41 and 39 patients, respectively. Those in the SWL group were treated on an outpatient basis with Medispec Econolith 2000 (Medispec, Germantown, Maryland) under intravenous sedation. The URSL was performed with a 6/7.5Fr semirigid tapered ureterorenoscope and holmium:YAG laser with the patient under spinal anesthesia on an inpatient basis. Successful outcome was defined as the patient being stone-free on radiography 1 month after treatment. Stone size, success rate, postoperative complications and cost were analyzed in each group. A total of 80 patients were enrolled in this study. Hematuria and flank pain were the most common complaints in each group. Mean stone size +/- SD was 1.28 +/- 0.04 cm in the SWL group and 1.51 +/- 0.05 cm in URSL group (p = 0.0009). Accessibility of the semirigid ureterorenoscope for impacted upper ureteral stones was 95.1% (39 of 41) and the stone-free rate achieved after 1 sitting was 92% (36 of 39). The initial stone-free rate of in situ SWL was 61% (25 of 41

  1. A comparison of the FREDDY and holmium lasers during ureteroscopic lithotripsy.

    PubMed

    Yates, Jennifer; Zabbo, August; Pareek, Gyan

    2007-09-01

    Two laser devices that are used today in endoscopic treatment of renal and ureteral calculi are the frequency-doubled double-pulse neodynium:YAG (FREDDY) and Holmium:YAG lasers. The mechanism of action of these lasers differs, thus conferring potentially different safety and efficacy profiles. The in vitro efficacy of these lasers in treating urinary stones has been explored, but to our knowledge no study compares the in vivo efficacy. The purpose of this study is to compare the stone-free and complication rates of the FREDDY and holmium lasers. Subjects were included in the study (from January 2004 to September 2006) if they had adequate documentation of stone size and location, postoperative stone burden, and perioperative complications. Stone-free status was determined based on intraoperative findings and postoperative imaging. Complications included bleeding, ureteral perforation, any intraoperative event necessitating termination of the procedure, ureteral stricture, hydronephrosis, and admission to the hospital with a diagnosis related to the procedure. Sixty patients with adequate follow-up were identified. Thirty patients were treated with FREDDY and 30 patients with Holmium laser. Fisher's exact test was employed for statistical analysis. There was no significant difference in the average stone size between the FREDDY and Holmium groups, which were 6.7 mm and 6.1 mm, respectively. Stone-free rates in the FREDDY and Holmium groups were 76.7% and 93.3%, respectively, P = 0.149. The complication rates were 17.4% in the FREDDY group and 10% in the Holmium group, P = 0.667. The complication and stone-free rates did not significantly differ between the FREDDY and Holmium lasers, though there was a trend toward a higher stone-free rate and lower complication rate with the holmium laser. Holmium laser may be more effective than the FREDDY laser in fragmenting calcium oxalate monohydrate stones. The device and laser fiber costs were comparable. 2007 Wiley-Liss, Inc

  2. Impact of pulse duration on Ho:YAG laser lithotripsy: treatment aspects on the single-pulse level.

    PubMed

    Sroka, Ronald; Pongratz, Thomas; Scheib, Gabriel; Khoder, Wael; Stief, Christian G; Herrmann, Thomas; Nagele, Udo; Bader, Markus J

    2015-04-01

    Holmium-YAG (Ho:YAG) laser lithotripsy is a multi-pulse treatment modality with stochastic effects on the fragmentation. In vitro investigation on the single-pulse-induced effects on fiber, repulsion as well as fragmentation was performed to identify potential impacts of different Ho:YAG laser pulse durations. A Ho:YAG laser system (Swiss LaserClast, EMS S.A., Nyon, Switzerland) with selectable long- or short-pulse mode was tested with regard to fiber burn back, the repulsion capacity using an underwater pendulum setup and single-pulse-induced fragmentation capacity using artificial (BEGO) stones. The laser parameters were chosen in accordance with clinical application modes (laser fiber: 365 and 200 µm; output power: 4, 6 and 10 W in different combinations of energy per pulse and repetition rate). Evaluation parameters were reduction in fiber length, pendulum deviation and topology of the crater. Using the long-pulse mode, the fiber burn back was nearly negligible, while in short-pulse mode, an increased burn back could be observed. The results of the pendulum test showed that the deviation induced by the momentum of short pulses was by factor 1.5-2 higher compared to longer pulses at identical energy per pulse settings. The ablation volumes induced by single pulses either in short-pulse or long-pulse mode did not differ significantly although different crater shapes appeared. Reduced stone repulsion and reduced laser fiber burn back with longer laser pulses may result in a more convenient handling during clinical application and thus in an improved clinical outcome of laser lithotripsy.

  3. Fiber optic muzzle brake tip for reducing fiber burnback and stone retropulsion during thulium fiber laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Hutchens, Thomas C.; Gonzalez, David A.; Irby, Pierce B.; Fried, Nathaniel M.

    2017-01-01

    The experimental thulium fiber laser (TFL) is being explored as an alternative to the current clinical gold standard Holmium:YAG laser for lithotripsy. The near single-mode TFL beam allows coupling of higher power into smaller optical fibers than the multimode Holmium laser beam profile, without proximal fiber tip degradation. A smaller fiber is desirable because it provides more space in the ureteroscope working channel for increased saline irrigation rates and allows maximum ureteroscope deflection. However, distal fiber tip burnback increases as fiber diameter decreases. Previous studies utilizing hollow steel sheaths around recessed distal fiber tips reduced fiber burnback but increased stone retropulsion. A "fiber muzzle brake" was tested for reducing both fiber burnback and stone retropulsion by manipulating vapor bubble expansion. TFL lithotripsy studies were performed at 1908 nm, 35 mJ, 500 μs, and 300 Hz using a 100-μm-core fiber. The optimal stainless steel muzzle brake tip tested consisted of a 1-cm-long, 560-μm-outer-diameter, 360-μm-inner-diameter tube with a 275-μm-diameter through hole located 250 μm from the distal end. The fiber tip was recessed a distance of 500 μm. Stone phantom retropulsion, fiber tip burnback, and calcium oxalate stone ablation studies were performed ex vivo. Small stones with a mass of 40±4 mg and 4-mm-diameter were ablated over a 1.5-mm sieve in 25±4 s (n=10) without visible distal fiber tip burnback. Reduction in stone phantom retropulsion distance by 50% and 85% was observed when using muzzle brake tips versus 100-μm-core bare fibers and hollow steel tip fibers, respectively. The muzzle brake fiber tip simultaneously provided efficient stone ablation, reduced stone retropulsion, and minimal fiber degradation during TFL lithotripsy.

  4. Holmium Laser Lithotripsy with Semi-Rigid Ureteroscopy: A First-Choice Treatment for Impacted Ureteral Stones in Children?

    PubMed Central

    Adanur, Senol; Aydin, Hasan Riza; Ozkaya, Fatih; Ziypak, Tevfik; Polat, Ozkan

    2014-01-01

    Background We aimed to assess the effectiveness of semi-rigid ureteroscopy and holmium laser lithotripsy in the treatment of impacted ureteral stones in children. Material/Methods We evaluated a total of 32 children under the age of 18 years treated with ureteroscopic holmium laser lithotripsy for impacted ureteral stones between January 2005 and July 2013. Their stone-free state was defined as the absence of any residual stone on radiologic evaluation performed 4 weeks postoperatively. Complications were evaluated according to the modified Clavien classification. Result The mean patient age was 9.5±5.1 years (range 1–18 years). Seven (21.8%) of the stones were located in the proximal ureter, 9 (28.2%) were in the mid-ureter, and 16 (50%) were in the distal ureter. The mean stone size was calculated as being 10.46±3.8 mm2 (range 5–20). The stone-free rate was 93.75% (30/32 patients) following primary URS. Additional treatment was required for only 2 (6.25%) of the patients. After the procedure, a D-J stent was placed in all the patients. The total complication rate was 15.6% (5 patients). The 10 total complications in these 5 patients were 5 (15.6%) Grade I, 1 (3.1%) Grade II, 2 (6.25%) Grade IIIa, and 2 (6.25%) Grade IIIb. The mean follow-up period was 16.5 months (range 3–55). Conclusions For the treatment of impacted ureteral stones in children, holmium laser lithotripsy with semi-rigid ureteroscopy, with its low retreatment requirement and acceptable complication rates, is an effective and reliable method in experienced and skilled hands as a first-choice treatment approach. PMID:25415256

  5. Gallstone disease: Symptoms, diagnosis and endoscopic management of common bile duct stones.

    PubMed

    Caddy, Grant R; Tham, Tony C K

    2006-01-01

    Bile duct stones (BDS) are often suspected on history and clinical examination alone but symptoms may be variable ranging from asymptomatic to complications such as biliary colic, pancreatitis, jaundice or cholangitis. The majority of BDS can be diagnosed by transabdominal ultrasound, computed tomography, endoscopic ultrasound or magnetic resonance cholangiography prior to endoscopic or laparoscopic removal. Approximately 90% of BDS can be removed following endoscopic retrograde cholangiography (ERC)+sphincterotomy. Most of the remaining stones can be removed using mechanical lithotripsy. Patients with uncorrected coagulopathies may be treated with ERC+pneumatic dilatation of the sphincter of Oddi. Shockwave lithotripsy (intraductal and extracorporeal) and laser lithotripsy have also been used to fragment large bile duct stones prior to endoscopic removal. The role of medical therapy in treatment of BDS is currently uncertain. This review focuses on the clinical presentation, investigation and current management of BDS.

  6. Retrograde intrarenal surgery with holmium-YAG laser lithotripsy in the primary treatment of renal lithiasis.

    PubMed

    Redondo, C; Ramón de Fata, F; Gimbernat, H; Meilán, E; Andrés, G; Angulo, J C

    2015-06-01

    retrograde intrarenal surgery (RIRS) appears as a safe and effective technique as well as a good therapeutic alternative to extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PNL). descriptive study in 50 patients surgically treated between November 2012 and April 2013. Demographic, operative and postoperative data as well as early and late complications data were collected. The minimum follow-up of patients was one year. Surgery was performed under general anesthesia. Flexible ureteroscopy with ureteral access sheath and laser fragmentation were employed. Surgery success was defined as stone free rate in postoperative control test and at three months after surgery (simple radiography, abdominal ultrasound or CT without contrast). mean age was 51.1±15.5 years old. The highest-frequency location was the lower calyceal group (26%), single stones were described in 58% of patients whilst multiple lithiasis were found in the 42%. Regarding the stone burden in 44% of the patients was low (<2 cm), and high (>3 cm) in 22% of the patients. The stone clearance rate was 89.7±17.5. Average surgery time was 96.6±35.2min. Complications were reported in 4 patients (8%), all of them early ones and minor in nature. RIRS is an effective and safe option whose results are comparable to ESWL and PCNL. RIRS can be considered as first-line treatment. These results are corroborated by numerous studies. To strengthen these findings, prospective studies focusing on quality of life, length of stay, complications and cost-effectiveness of different treatments are needed. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  7. Fluoroscopy free flexible ureteroscopy with holmium: Yttrium-aluminium-garnet laser lithotripsy for removal of renal calculi.

    PubMed

    Aboutaleb, Hamdy

    2016-06-01

    To evaluate the feasibility of access sheath insertion and ureteric stent placement without image guidance in flexible ureteroscopic lithotripsy with holmium:yttrium-aluminium-garnet laser for renal stones. Between March 2014 and October 2015, 80 patients with renal stones treated with flexible ureteroscopic laser lithotripsy were evaluated. Indications for surgery were renal obstruction, failed shockwave lithotripsy (SWL), stones in polycystic kidneys, and mal-rotated kidneys. A 6.5-F Cobra flexible ureteroscope was used in all cases with an access sheath of 12 F, 35/45 cm in length. Fluoroscopy was not intended for use in all cases and postoperative JJ stenting was optional. The perioperative complications were listed and the collected data were analysed. The study included 80 patients (66 male, 14 female), with a mean (SD; range) age of 48.2 (8; 28-54) years and a stone burden of 13 (3.5; range 6-23) mm. In all, 26 patients had a stone burden of >15 mm and 48 patients had lower calyceal stones. The mean (SD; range) operative time was 71.5 (20; 25-130) min. Overall, 76 (95%) access sheath insertions were performed successfully without the use of fluoroscopy. JJ stenting was used in 22 patients (27.5%). The mean (SD; range) hospital stay was 10 (8.5; 10-36) h. After one session, a stone-free rate (SFR) of 87.5% was achieved (93.3% for stones of <15 mm). A single session was successful in 87.9% of cases with lower calyceal stones, with a SFR of 91.7% for post-SWL failure cases. The perioperative complication rate was 15%. Access sheath insertion without fluoroscopic guidance is feasible. This technique reduces radiation exposure in patients requiring flexible ureteroscopy.

  8. Evaluation of pneumatic versus holmium:YAG laser lithotripsy for impacted ureteral stones.

    PubMed

    Binbay, Murat; Tepeler, Abdulkadir; Singh, Avinash; Akman, Tolga; Tekinaslan, Erdem; Sarilar, Omer; Baykal, Murat; Muslumanoglu, Ahmet Yaser

    2011-12-01

    We prospectively analyzed and compared the effectiveness and complications of pneumatic lithotripter with a holmium:yttrium-aluminum-garnet (Ho:YAG) laser for the ureterorenoscopic management of impacted ureteral stones. From January 2006 to January 2008, we performed retrograde endoscopic treatment in 288 patients with ureteral stones in our clinic. The patients with impacted stones were randomized into two groups according to the lithotripter used to fragment the stone: pneumatic (n = 40) and laser (n = 40). The preoperative, operative, and post-operative follow-up findings were analyzed and compared. The average stone size was similar in both groups (118.8 ± 58.3 mm(2) vs. 110.7 ± 54.4 mm(2)). The calculi were located in the distal ureter in most of the patients in both groups (65% in pneumatic group and 52.5% in laser group). The operation time was significantly diminished in the laser group (P = 0.001). The stone-free rates after a single ureteroscopic procedure were 80 and 97.5% in the pneumatic and laser groups, respectively (P = 0.03). Auxiliary treatments were needed in seven patients in the pneumatic group, while only one patient in the laser group (P = 0.05) needed this treatment. After the additional procedures, a 100% success rate was achieved in both groups. The rate of double J stent insertion was significantly higher in the pneumatic group (P = 0.01). In the pneumatic group, four cases of stone up-migration and one case of post-operative stricture were seen, whereas only one case of stone up-migration was noted in the laser group. Our comparative study has shown that the use of Ho:YAG as an intracorporeal lithotripter during ureteroscopic management of impacted ureteral stones is highly efficient with high success rates, regardless of the stone location.

  9. Comparison of Ho:YAG laser and pneumatic lithotripsy in the treatment of impacted ureteral stones: an analysis of risk factors.

    PubMed

    Degirmenci, Tansu; Gunlusoy, Bulent; Kozacioglu, Zafer; Arslan, Murat; Koras, Omer; Arslan, Burak; Minareci, Suleyman

    2014-03-01

    The aim was to compare pneumatic and holmium:yttrium-aluminum-garnet laser in the treatment of impacted ureteral stones with different locations and to identify the risk factors for complications. Between March 2005 and November 2012, a total of 230 patients underwent ureteroscopic lithotripsy for impacted stones. Of the patients, 117 had pneumatic and 113 had laser lithotripsy for the fragmentation of the stones. Treatment outcomes based on evidence of being stone free were evaluated. Preoperative, operative, and postoperative follow-up findings were analyzed and compared. There was a difference between the two groups according to overall stone clearance rate (93.8% vs. 80.3%, p = 0.002). There was no statistically significant difference for distal location between the laser and pneumatic groups (96.8% vs. 91.7%, p =0.288). For 10 patients with intrarenally migrated stones who were managed with flexible ureterorenoscopy in the same session, laser lithotripsy was more successful than pneumatic for proximal ureteral stone (94.4% vs. 67.9%, p = 0.007). The overall complication rate was 26.1%. There was no statistically significant difference between the two groups (29% vs. 23%, p = 0.296). Multivariate logistic regression analysis revealed that the proximal location was a statistically significant parameter for the occurrence of complications in both groups (p = 0.001 for PL, p = 0.004 for laser). The pneumatic and holmium:yttrium-aluminum-garnet laser lithotripsy are effective in the treatment of distal impacted stones. Both treatments with semirigid ureteroscopy are acceptable for proximal impacted ureteral stones, but holmium laser lithotripsy has an advantage of use with flexible ureteroscope for intrarenally migrated stone. Copyright © 2013. Published by Elsevier B.V.

  10. Effectiveness of oral litholysis therapy for improving glucose intolerance and malnutrition in patients with poor results following endoscopic therapy and extracorporeal shock wave lithotripsy for calcified pancreatic stones.

    PubMed

    Ashizawa, Nobuo; Hamano, Koichi; Noda, Aiji

    2015-10-01

    We report a case of pancreatolithiasis in which glucose intolerance and malnutrition were significantly improved after starting oral litholysis therapy (OLT) with use of trimethadione. A 43-year-old female with multiple calcified stones in the main and peripheral pancreatic ducts had experienced recurrent and severe attacks of pain for 7 years (from 21 to28 years of age). Impaired glucose tolerance was first noted at the age of 32 years. We started OLT after interventional endoscopic therapy combined with extracorporeal shock wave lithotripsy failed because of kink and stenosis of the main pancreatic duct (MPD). Over the next 9 years, a significant decrease in total pancreatic calcified stone volume was shown by computer analysis of follow-up computed tomography images. Larger stones completely disappeared without attacks of pain. In addition, both glucose intolerance and insulin secretion were significantly ameliorated, followed by improvement of malnutrition. OLT may induce intraductal decompression by dissolving stones in the peripheral ducts as well as the MPD, with resulting preservation of endocrine function and improvement of malnutrition. Since the present results were obtained in a single case, further clinical trials are necessary to evaluate the value of performing OLT under various conditions to eliminate stones.

  11. [Flexible ureterorenoscopy and laser lithotripsy for upper urinary tract stones in neurologic patients with severe motor disability].

    PubMed

    Madec, F-X; Suply, E; Luyckx, F; Nedelec, M; Chowaniec, Y; Branchereau, J; Le Normand, L; Glemain, P

    2017-05-01

    The study's objective was to evaluate the effectiveness and morbidity of flexible ureterorenoscopy and laser lithotripsy for upper urinary tract stones in patients with a nervous system pathology including severe motor disability. Between 2006 and 2013, we retrospectively analyzed 83 flexible ureterorenoscopy to treat 63 kidneys in 42 patients. Stone free (SF) kidneys defined as an absence of stones on computerized tomography, renal ultrasound, X-ray or direct ureterorenoscopy, were considered a surgical success. Complications were classified according to the Clavien-Dindo system. Success rates were 49.2 %, 57.1 % and 58.7 %, respectively after first, second and third flexible ureterorenoscopy procedure. Clearance after one procedure was achieved in 64.3 % of cases involving less than 20mm stones. No major complication (Clavien-Dindo>2) was described (0 %). Complication rates were 44.7 %, with 31.6 % Clavien-Dindo 2. The main complication was urosepsis, which occurred in 27.6 % of cases. Flexible ureteroscopy and laser lithotripsies for upper urinary tract stones in neurologic patients with severe motor disability are associated with a lower success rate and some frequent low grade complications compared to overall population. In clinical practice, the indications of flexible ureterorenoscopy for these patients seem restricted. 5. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Characterization of calculus migration during Ho:YAG laser lithotripsy by high speed camera using suspended pendulum method

    NASA Astrophysics Data System (ADS)

    Zhang, Jian James; Rajabhandharaks, Danop; Xuan, Jason Rongwei; Chia, Ray W. J.; Hasenberg, Tom

    2014-03-01

    Calculus migration is a common problem during ureteroscopic laser lithotripsy procedure to treat urolithiasis. A conventional experimental method to characterize calculus migration utilized a hosting container (e.g. a "V" grove or a test tube). These methods, however, demonstrated large variation and poor detectability, possibly attributing to friction between the calculus and the container on which the calculus was situated. In this study, calculus migration was investigated using a pendulum model suspended under water to eliminate the aforementioned friction. A high speed camera was used to study the movement of the calculus which covered zero order (displacement), 1st order (speed) and 2nd order (acceleration). A commercialized, pulsed Ho:YAG laser at 2.1 um, 365-um core fiber, and calculus phantom (Plaster of Paris, 10×10×10mm cube) were utilized to mimic laser lithotripsy procedure. The phantom was hung on a stainless steel bar and irradiated by the laser at 0.5, 1.0 and 1.5J energy per pulse at 10Hz for 1 second (i.e., 5, 10, and 15W). Movement of the phantom was recorded by a high-speed camera with a frame rate of 10,000 FPS. Maximum displacement was 1.25+/-0.10, 3.01+/-0.52, and 4.37+/-0.58 mm for 0.5, 1, and 1.5J energy per pulse, respectively. Using the same laser power, the conventional method showed <0.5 mm total displacement. When reducing the phantom size to 5×5×5mm (1/8 in volume), the displacement was very inconsistent. The results suggested that using the pendulum model to eliminate the friction improved sensitivity and repeatability of the experiment. Detailed investigation on calculus movement and other causes of experimental variation will be conducted as a future study.

  13. Endoscopic laser scalpel for head and neck cancer surgery

    NASA Astrophysics Data System (ADS)

    Patel, Snehal; Rajadhyaksha, Milind; Kirov, Stefan; Li, Yongbiao; Toledo-Crow, Ricardo

    2012-02-01

    Minimally invasive surgical (MIS) techniques, such as laparoscopic surgery and endoscopy, provide reliable disease control with reduced impact on the function of the diseased organ. Surgical lasers can ablate, cut and excise tissue while sealing small blood vessels minimizing bleeding and risk of lymphatic metastases from tumors. Lasers with wavelengths in the IR are readily absorbed by water causing minimal thermal damage to adjacent tissue, ideal for surgery near critical anatomical structures. MIS techniques have largely been unable to adopt the use of lasers partly due to the difficulty in bringing the laser into the endoscopic cavity. Hollow waveguide fibers have been adapted to bring surgical lasers to endoscopy. However, they deliver a beam that diverges rapidly and requires careful manipulation of the fiber tip relative to the target. Thus, the principal obstacle for surgical lasers in MIS procedures has been a lack of effective control instruments to manipulate the laser in the body cavity and accurately deliver it to the targeted tissue. To overcome this limitation, we have designed and built an endoscopic laser system that incorporates a miniature dual wedge beam steering device, a video camera, and the control system for remote and /or robotic operation. The dual wedge Risley device offers the smallest profile possible for endoscopic use. Clinical specifications and design considerations will be presented together with descriptions of the device and the development of its control system.

  14. A Prospective Randomized Trial Comparing Pneumatic Lithotripsy and Holmium Laser for Management of Middle and Distal Ureteral Calculi.

    PubMed

    Li, Linjin; Pan, Yue; Weng, Zhiliang; Bao, Wenshuo; Yu, Zhixian; Wang, Feng

    2015-08-01

    The aim of this study was to compare the efficacy and safety between pneumatic and holmium:yttrium-aluminum-garnet (Ho:YAG) laser in the treatment of patients with ureteral stones located in the middle and distal ureter. We conducted a prospective study in recruiting 982 eligible patients from 2009 to 2012. Patients were randomly divided into two groups-the pneumatic lithotripsy (PL) group or the Ho:YAG laser lithotripsy (LL) group. Patient demographics, stone characteristics, intraoperative parameters, and postoperative complications were evaluated and analyzed. The baseline demographics of patients and stone characteristics were similar in the two groups. The LL group showed significant benefits compared with the PL group in terms of mean operative time (28±9.2 vs 41±12.4 min, P=0.001) and early stone-free rate (80.8% vs 91.3%, P=0.04), but there was no statistically significant difference at the third month (92.6% vs 95.5%, P=0.15). In the LL group, 24 postoperative cases of stricture were seen, whereas only 5 cases occurred in the PL group (P=0.02). The other complications, such as perforation, bleeding, and mucosal injury, were comparable in the two groups. The average postoperative stay was also similar (1.7±2.4 days for PL and 1.5±3.1 days for LL (P=0.62). Both PL and LL are effective in the management of middle and distal impacted stones. Ho:YAG laser has advantages in better efficacy of stone fragmentation and a higher early stone-free rate but seems to have to face the increased risks of postoperative stricture.

  15. Endoscopic laser treatment of subglottic and tracheal stenosis

    NASA Astrophysics Data System (ADS)

    Correa, Alex J.; Garrett, C. Gaelyn; Reinisch, Lou

    1999-06-01

    The ideal laser produces discrete wounds in a reproducible manner. The CO2 laser with its 10.6 micron wavelength is highly absorbed by water, its energy concentrated at the point of impact and the longer wavelength creates less scatter in tissue. The development of binocular endoscopic delivery system for use with binocular microlaryngoscopes have aided in using CO2 laser to treat patients with subglottic and tracheal stenosis. Often, patients with these disease processes require multiple endoscopic or open reconstructive procedures and my ultimately become tracheotomy dependent. The canine model of subglottic stenosis that has been develop allows testing of new agents as adjuncts to laser treatment. Mitomycin-C is an antibiotic with antitumor activity used in chemotherapy and also in ophthalmologic surgery due to its known inhibition of fibroblast proliferation. Current studies indicate this drug to have significant potential for improving our current management of this disease process.

  16. Does stone entrapment with ″Uro-Net″ improve Ho:YAG laser lithotripsy efficiency in percutaneous nephrolithotomy and cystolithopaxy?: an in vitro study.

    PubMed

    Marchini, Giovanni Scala; Rai, Aayushi; De, Shubha; Sarkissian, Carl; Monga, Manoj

    2013-01-01

    to test the effect of stone entrapment on laser lithotripsy efficiency. Spherical stone phantoms were created using the BegoStone® plaster. Lithotripsy of one stone (1.0 g) per test jar was performed with Ho:YAG laser (365 µm fiber; 1 minute/trial). Four laser settings were tested: I-0.8 J,8 Hz; II-0.2J,50 Hz; III-0.5 J,50 Hz; IV-1.5 J,40 Hz. Uro-Net (US Endoscopy) deployment was used in 3/9 trials. Post-treatment, stone fragments were strained though a 1mm sieve; after a 7-day drying period fragments and unfragmented stone were weighed. Uro-Net nylon mesh and wire frame resistance were tested (laser fired for 30s). All nets used were evaluated for functionality and strength (compared to 10 new nets). Student's T test was used to compare the studied parameters; significance was set at p < 0.05. Laser settings I and II caused less damage to the net overall; the mesh and wire frame had worst injuries with setting IV; setting III had an intermediate outcome; 42% of nets were rendered unusable and excluded from strength analysis. There was no difference in mean strength between used functional nets and non-used devices (8.05 vs. 7.45 lbs, respectively; p = 0.14). Setting IV was the most efficient for lithotripsy (1.9 ± 0.6 mg/s; p < 0.001) with or without net stabilization; setting III was superior to I and II only if a net was not used. Laser lithotripsy is not optimized by stone entrapment with a net retrieval device which may be damaged by high energy laser settings.

  17. Endoscopic laser reshaping of rabbit tracheal cartilage: preliminary investigations

    NASA Astrophysics Data System (ADS)

    Tsang, Walter; Lam, Anthony; Protsenko, Dmitry; Wong, Brian J.

    2005-04-01

    Background: Tracheal cartilage deformities due to trauma, prolonged endotracheal intubation or infection are difficult to correct. Current treatment options such as dilation, laser ablation, stent placement, and segmental resection are only temporary or carry significant risks. The objectives of this project were to design and test a laser activated endotracheal stent system that can actively modify the geometry of tracheal cartilage, leading to permanent retention of a new and desirable tracheal geometry. Methods: Ex vivo rabbit tracheal cartilage (simulating human neonate trachea) were irradiated with an Er: Glass laser, (λ= 1.54um, 0.5W-2.5W, 1 sec to 5 sec). Shape change and gross thermal injury were assessed visually to determine the best laser power parameters for reshaping. A rigid endoscopic telescope and hollow bronchoscope were used to record endoscopic images. The stent was constructed from nitinol wire, shaped into a zigzag configuration. An ex vivo testing apparatus was also constructed. Results: The best laser power parameter to produce shape change was 1 W for 6-7 seconds. At this setting, there was significant shape change with only minimal thermal injury to the tracheal mucosa, as assessed by visual inspection. The bronchoscopy system functioned adequately during testing in the ex vivo testing apparatus. Conclusion: We have successfully designed instrumentation and created the capability to endoscopically reshape tracheal cartilage in an ex vivo rabbit model. The results obtained in ex vivo tracheal cartilage indicated that reshaping using Er: Glass laser can be accomplished.

  18. The study of laser pulse width on efficiency of Ho:YAG laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Zhang, Jian J.; Rutherford, Jonathan; Solomon, Metasebya; Cheng, Brian; Xuan, Jason R.; Gong, Jason; Yu, Honggang; Xia, Michael; Yang, Xirong; Hasenberg, Thomas; Curran, Sean

    2017-02-01

    When treating ureteral calculi, retropulsion can be reduced by using a longer pulse width without compromising fragmentation efficiency (from the studies by David S. Finley et al. and Hyun Wook Kang et al.). In this study, a lab build Ho:YAG laser was used as the laser pulse source, with pulse energy from 0.2J up to 3.0 J, and electrical pump pulse width from 150 us up to 1000 us. The fiber used in the investigation is a 365 μm core diameter fiber, SureFlexTM, Model S-LLF365. Plaster of Paris calculus phantoms were ablated at different energy levels (0.2, 0.5, 1, 2, 3J) and with different number of pulses (1, 3, 10) using different electrical pump pulse width (333, 667, 1000 μs). The dynamics of the recoil action of a calculus phantom was monitored using a high-speed camera with frame rate up to 1 million frame per second (Photron Fastcam SA5); and the laser-induced craters were evaluated with a 3-D digital microscope (Keyence VHX-900F). A design of experiment software (DesignExpert-10, Minneapolis, MN, USA) is used in this study for the best fit of surface response on volume of dusting and retropulsion amplitude. The numerical formulas for the response surfaces of dusting speed and retropulsion amplitude are generated. More detailed investigation on the optimal conditions for dusting of other kinds of stone samples and the fiber size effect will be conducted as a future study.

  19. Noncontact laser fiber delivery system for endoscopic medical applications

    NASA Astrophysics Data System (ADS)

    Denisov, Nikolay A.; Griffin, Stephen E.

    1999-02-01

    The objective of the study was to design and to investigate laser fiber delivery system for treatment of obstructed human internal tubular organs using endoscopic techniques. This system eliminates the main disadvantages of both applied contact and non-contact probes, namely surface contamination with concomitant hydrothermal probe deterioration and large beam divergence with poor energy density, respectively. Proposed silica or sapphire probes produce quasi-collimated beam with specific outside diameter and power distribution. To provide comparative analysis of laser delivery systems' optical properties with non-contact endoscopic probes 'steady beam distance' (SBD) and 'steady beam ratio' (SBR) coefficients are proposed. The calculation results are presented in the form of the plots of the SBR - coefficients and SBDs for a 2.0 mm specific outside beam diameter versus laser wavelength, delivery fiber core diameter and its numerical aperture for both probe material. Additionally, the cross power distributions along the SBD were studied. Results obtained could provide a useful tool to designers of non-contact fiber delivery systems intended for a variety of medical applications, including endoscopic surgery with cw or pulse laser tissue irradiation, skin de-epithelialization, laser-induced fluorescence and photodynamic therapy.

  20. A Miniaturized, 1.9F Integrated Optical Fiber and Stone Basket for Use in Thulium Fiber Laser Lithotripsy.

    PubMed

    Wilson, Christopher R; Hutchens, Thomas C; Hardy, Luke A; Irby, Pierce B; Fried, Nathaniel M

    2015-10-01

    The thulium fiber laser (TFL) is being explored as an alternative laser lithotripter to the standard holmium:yttrium-aluminum-garnet laser. The more uniform beam profile of the TFL enables higher power transmission through smaller fibers. In this study, a 100-μm core, 140-μm outer-diameter (OD) silica fiber with 5-mm length hollow steel tip was integrated with 1.3F (0.433-mm OD) nitinol wire basket to form a 1.9F (0.633-mm OD) device. TFL energy of 30 mJ, 500 μs pulse duration, and 500 Hz pulse rate was delivered to human uric acid stones, ex vivo. Stone ablation rates measured 1.5 ± 0.2 mg/s, comparable to 1.7 ± 0.3 mg/s using bare fiber tips separately with stone basket. With further development, this device may minimize stone retropulsion, allowing more efficient TFL lithotripsy at higher pulse rates. It may also provide increased flexibility, higher saline irrigation rates through the ureteroscope working channel, reduce fiber degradation compared with separate fiber and basket manipulation, and reduce laser-induced nitinol wire damage.

  1. Laser lithotripsy of gallstones: alexandrite and rhodamine-6G versus coumarin dye laser: fragmentation and fiber burn-off in vitro

    NASA Astrophysics Data System (ADS)

    Hochberger, Juergen; Bredt, Marion; Mueller, Gudrun; Hahn, Eckhart G.; Ell, Christian

    1993-05-01

    In the following study three different pulsed laser lithotripsy systems were compared for the fine fragmentation of identical sets of natural and synthetic gallstones `in vitro.' Using a pulsed coumarin dye laser (504 nm), a pulsed rhodamine 6G dye laser (595 nm), and a pulsed Alexandrite laser (755 nm) a total of 184 concrements of known chemical composition, size, and weight were disintegrated to a fragment size of laser parameters. All stones could be reliably disintegrated using the three laser systems at the different settings tested. Even though in our experimental set up the rhodamine 6G dye laser showed the best results, theses were not statistically significant to results obtained with the coumarin dye and the Alexandrite laser at high pulse energies. The mean fiber burn-off of the Alexandrite laser at 80 mJ (Do80:195 mm/cm3 stone vol.) was however 5 to 81 fold higher than with all other laser systems, a fact of clinical relevance as far as possible side effects of the quartz material in the bile duct are not yet known.

  2. Color vision deficits during laser lithotripsy using safety goggles for coumarin green or alexandrite but not with holmium:YAG laser safety goggles.

    PubMed

    Teichman, J M; Johnson, A J; Yates, J T; Angle, B N; Dirks, M S; Muirhead, J T; Thompson, I M; Pearle, M S

    1998-03-01

    Laser lithotripsy requires urologists to wear laser eye protection. Laser eye protection devices screen out specific light wavelengths and may distort color perception. This study tests whether urologists risk color confusion when wearing laser eye protection devices for laser lithotripsy. Urologists were tested with the Farnsworth Dichotomous Test for Color Blindness (D-15) and the Farnsworth-Munsell 100-Hue Test (FM-100) without (control) and with laser eye protection devices for coumarin green, alexandrite and holmium:YAG lasers. Error scores were tabulated. The pattern of color deficits was characterized with confusion angles, confusion index (C-index), scatter index (S-index) and color axes. Laser eye protection devices were tested with spectrophotometry for spectral transmittance and optical density. The D-15 transposition errors (mean plus or minus standard deviation) for control, holmium:YAG, alexandrite and coumarin green laser eye protection were 0 +/- 0, 0 +/- 0, 0.3 +/- 0.5 and 6.4 +/- 1.6, respectively (p = 0.0000001). The FM-100 error scores (mean plus or minus standard deviation) were 20 +/- 15, 20 +/- 14, 91 +/- 32 and 319 +/- 69, respectively (p = 0.0001). The confusion index scores indicated a mild color confusion for the alexandrite and pronounced color confusion for the coumarin green laser eye protection. The confusion angles and scatter indexes mimicked a congenital blue-yellow deficit for coumarin green laser eye protection. Color axes showed no significant deficits for control or holmium:YAG laser eye protection in any subject, red-green axis deficits in 3 of 6 tested with alexandrite and blue-yellow axis deficits in 12 of 12 tested with coumarin green (p < 0.001). Spectrophotometry showed that laser eye protection for coumarin green blocks light less than 550 nm., alexandrite blocks light greater than 650 nm. and holmium:YAG blocks light greater than 825 nm. Laser eye protection for coumarin green causes pronounced blue-yellow color

  3. Calculus migration characterization during Ho:YAG laser lithotripsy by high-speed camera using suspended pendulum method.

    PubMed

    Zhang, Jian James; Rajabhandharaks, Danop; Xuan, Jason Rongwei; Chia, Ray W J; Hasenberg, Thomas

    2017-07-01

    Calculus migration is a common problem during ureteroscopic laser lithotripsy procedure to treat urolithiasis. A conventional experimental method to characterize calculus migration utilized a hosting container (e.g., a "V" grove or a test tube). These methods, however, demonstrated large variation and poor detectability, possibly attributed to the friction between the calculus and the container on which the calculus was situated. In this study, calculus migration was investigated using a pendulum model suspended underwater to eliminate the aforementioned friction. A high-speed camera was used to study the movement of the calculus which covered zero order (displacement), first order (speed), and second order (acceleration). A commercialized, pulsed Ho:YAG laser at 2.1 μm, a 365-μm core diameter fiber, and a calculus phantom (Plaster of Paris, 10 × 10 × 10 mm(3)) was utilized to mimic laser lithotripsy procedure. The phantom was hung on a stainless steel bar and irradiated by the laser at 0.5, 1.0, and 1.5 J energy per pulse at 10 Hz for 1 s (i.e., 5, 10, and 15 W). Movement of the phantom was recorded by a high-speed camera with a frame rate of 10,000 FPS. The video data files are analyzed by MATLAB program by processing each image frame and obtaining position data of the calculus. With a sample size of 10, the maximum displacement was 1.25 ± 0.10, 3.01 ± 0.52, and 4.37 ± 0.58 mm for 0.5, 1, and 1.5 J energy per pulse, respectively. Using the same laser power, the conventional method showed <0.5 mm total displacement. When reducing the phantom size to 5 × 5 × 5 mm(3) (one eighth in volume), the displacement was very inconsistent. The results suggested that using the pendulum model to eliminate the friction improved sensitivity and repeatability of the experiment. A detailed investigation on calculus movement and other causes of experimental variation will be conducted as a future study.

  4. Comparison of holmium:YAG and thulium fiber laser lithotripsy: ablation thresholds, ablation rates, and retropulsion effects.

    PubMed

    Blackmon, Richard L; Irby, Pierce B; Fried, Nathaniel M

    2011-07-01

    The holmium:YAG (Ho:YAG) laser lithotriptor is capable of operating at high pulse energies, but efficient operation is limited to low pulse rates (∼10 Hz) during lithotripsy. On the contrary, the thulium fiber laser (TFL) is limited to low pulse energies, but can operate efficiently at high pulse rates (up to 1000 Hz). This study compares stone ablation threshold, ablation rate, and retropulsion for the two different Ho:YAG and TFL operation modes. The TFL (λ = 1908 nm) was operated with pulse energies of 5 to 35 mJ, 500-μs pulse duration, and pulse rates of 10 to 400 Hz. The Ho:YAG laser (λ = 2120 nm) was operated with pulse energies of 30 to 550 mJ, 350-μs pulse duration, and a pulse rate of 10 Hz. Laser energy was delivered through 200- and 270-μm-core optical fibers in contact mode with human calcium oxalate monohydrate (COM) stones for ablation studies and plaster-of-Paris stone phantoms for retropulsion studies. The COM stone ablation threshold for Ho:YAG and TFL measured 82.6 and 20.8 J∕cm(2), respectively. Stone retropulsion with the Ho:YAG laser linearly increased with pulse energy. Retropulsion with TFL was minimal at pulse rates less than 150 Hz, then rapidly increased at higher pulse rates. For minimal stone retropulsion, Ho:YAG operation at pulse energies less than 175 mJ at 10 Hz and TFL operation at 35 mJ at 100 Hz is recommended, with both lasers producing comparable ablation rates. Further development of a TFL operating with both high pulse energies of 100 to 200 mJ and high pulse rates of 100 to 150 Hz may also provide an alternative to the Ho:YAG laser for higher ablation rates, when retropulsion is not a primary concern.

  5. Comparison of holmium:YAG and thulium fiber laser lithotripsy: ablation thresholds, ablation rates, and retropulsion effects

    NASA Astrophysics Data System (ADS)

    Blackmon, Richard L.; Irby, Pierce B.; Fried, Nathaniel M.

    2011-07-01

    The holmium:YAG (Ho:YAG) laser lithotriptor is capable of operating at high pulse energies, but efficient operation is limited to low pulse rates (~10 Hz) during lithotripsy. On the contrary, the thulium fiber laser (TFL) is limited to low pulse energies, but can operate efficiently at high pulse rates (up to 1000 Hz). This study compares stone ablation threshold, ablation rate, and retropulsion for the two different Ho:YAG and TFL operation modes. The TFL (λ = 1908 nm) was operated with pulse energies of 5 to 35 mJ, 500-μs pulse duration, and pulse rates of 10 to 400 Hz. The Ho:YAG laser (λ = 2120 nm) was operated with pulse energies of 30 to 550 mJ, 350-μs pulse duration, and a pulse rate of 10 Hz. Laser energy was delivered through 200- and 270-μm-core optical fibers in contact mode with human calcium oxalate monohydrate (COM) stones for ablation studies and plaster-of-Paris stone phantoms for retropulsion studies. The COM stone ablation threshold for Ho:YAG and TFL measured 82.6 and 20.8 J/cm2, respectively. Stone retropulsion with the Ho:YAG laser linearly increased with pulse energy. Retropulsion with TFL was minimal at pulse rates less than 150 Hz, then rapidly increased at higher pulse rates. For minimal stone retropulsion, Ho:YAG operation at pulse energies less than 175 mJ at 10 Hz and TFL operation at 35 mJ at 100 Hz is recommended, with both lasers producing comparable ablation rates. Further development of a TFL operating with both high pulse energies of 100 to 200 mJ and high pulse rates of 100 to 150 Hz may also provide an alternative to the Ho:YAG laser for higher ablation rates, when retropulsion is not a primary concern.

  6. Kidney stone ablation times and peak saline temperatures during Holmium:YAG and Thulium fiber laser lithotripsy, in vitro, in a ureteral model

    NASA Astrophysics Data System (ADS)

    Hardy, Luke A.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

    2015-02-01

    Using a validated in vitro ureter model for laser lithotripsy, the performance of an experimental Thulium fiber laser (TFL) was studied and compared to clinical gold standard Holmium:YAG laser. The Holmium laser (λ = 2120 nm) was operated with standard parameters of 600 mJ, 350 μs, 6 Hz, and 270-μm-core optical fiber. TFL (λ = 1908 nm) was operated with 35 mJ, 500 μs, 150-500 Hz, and 100-μm-core fiber. Urinary stones (60% calcium oxalate monohydrate / 40% calcium phosphate), of uniform mass and diameter (4-5 mm) were laser ablated with fibers through a flexible video-ureteroscope under saline irrigation with flow rates of 22.7 ml/min and 13.7 ml/min for the TFL and Holmium laser, respectively. The temperature 3 mm from tube's center and 1 mm above mesh sieve was measured by a thermocouple and recorded during experiments. Total laser and operation times were recorded once all stone fragments passed through a 1.5-mm sieve. Holmium laser time measured 167 +/- 41 s (n = 12). TFL times measured 111 +/- 49 s, 39 +/- 11 s, and 23 +/- 4 s, for pulse rates of 150, 300, and 500 Hz (n = 12 each). Mean peak saline irrigation temperatures reached 24 +/- 1 °C for Holmium, and 33 +/- 3 °C, 33 +/- 7 °C, and 39 +/- 6 °C, for TFL at pulse rates of 150, 300, and 500 Hz. To avoid thermal buildup and provide a sufficient safety margin, TFL lithotripsy should be performed with pulse rates below 500 Hz and/or increased saline irrigation rates. The TFL rapidly fragmented kidney stones due in part to its high pulse rate, high power density, high average power, and reduced stone retropulsion, and may provide a clinical alternative to the conventional Holmium laser for lithotripsy.

  7. Endoscopic laser therapy for obstructing tracheobronchial lesions.

    PubMed

    Beamis, J F; Vergos, K; Rebeiz, E E; Shapshay, S M

    1991-05-01

    The Lahey Clinic experience using laser bronchoscopy for relief of obstructive tracheobronchial lesions during a 7-year period from 1982 to 1989 involves 269 patients treated with 400 procedures. The carbon dioxide (CO2) laser was used for tracheal stenosis and granulation tissue. The neodymium:yttrium-aluminum-garnet (Nd:YAG) laser was used for all obstructing endobronchial neoplasms. Indications for therapy included severe dyspnea, hemoptysis, and postobstructive pneumonitis. All patients had relatively central lesions. A rigid bronchoscope was used to treat 88% of patients, and 12% of patients were treated with a flexible bronchoscope. One death occurred during the intraoperative period. Eleven deaths occurred within 1 week of therapy and were related to the presence of extensive malignant lesions or to coronary artery disease. Our experience indicates that bronchoscopic application of the CO2 or Nd:YAG laser affords effective palliation for patients with obstructive tracheobronchial lesions. The Nd:YAG laser is recommended for patients with bulky vascular endobronchial neoplasms, and the CO2 laser is best reserved for patients with benign tracheal stenosis and granulation tissue.

  8. Endoscopic diode laser therapy for chronic radiation proctitis.

    PubMed

    Polese, Lino; Marini, Lucia; Rizzato, Roberto; Picardi, Edgardo; Merigliano, Stefano

    2017-09-11

    The purpose of this study is to determine the effectiveness of endoscopic diode laser therapy in patients presenting rectal bleeding due to chronic radiation proctitis (CRP). A retrospective analysis of CRP patients who underwent diode laser therapy in a single institution between 2010 and 2016 was carried out. The patients were treated by non-contact fibers without sedation in an outpatient setting. Fourteen patients (median age 77, range 73-87 years) diagnosed with CRP who had undergone high-dose radiotherapy for prostatic cancer and who presented with rectal bleeding were included. Six required blood transfusions. Antiplatelet (three patients) and anticoagulant (two patients) therapy was not suspended during the treatments. The patients underwent a median of two sessions; overall, a mean of 1684 J of laser energy per session was used. Bleeding was resolved in 10/14 (71%) patients, and other two patients showed improvement (93%). Only one patient, who did not complete the treatment, required blood transfusions after laser therapy; no complications were noted during or after the procedures. Study findings demonstrated that endoscopic non-contact diode laser treatment is safe and effective in CRP patients, even in those receiving antiplatelet and/or anticoagulant therapy.

  9. Endoscopic submucosal dissection using a carbon dioxide laser with submucosally injected laser absorber solution (porcine model).

    PubMed

    Obata, Daisuke; Morita, Yoshinori; Kawaguchi, Rinna; Ishii, Katsunori; Hazama, Hisanao; Awazu, Kunio; Kutsumi, Hiromu; Azuma, Takeshi

    2013-11-01

    Recently, endoscopic submucosal dissection (ESD) has been performed to treat early gastric cancer. The en bloc resection rate of ESD has been reported to be higher than that of conventional endoscopic mucosal resection (EMR), and ESD can resect larger lesions than EMR. However, ESD displays a higher complication rate than conventional EMR. Therefore, the development of devices that would increase the safety of ESD is desired. Lasers have been extensively studied as a possible alternative to electrosurgical tools. However, laser by itself easily resulted in perforation upon irradiation of the gastrointestinal tract. We hypothesized that performing ESD using a CO2 laser with a submucosal laser absorber could be a safe and simple treatment for early gastric cancer. To provide proof of concept regarding the feasibility of ESD using a CO2 laser with submucosally injected laser absorber solution, an experimental study in ex vivo and in vivo porcine models was performed. Five endoscopic experimental procedures using a carbon dioxide (CO2) laser were performed in a resected porcine stomach. In addition, three endoscopic experimental procedures using a CO2 laser were performed in living pigs. In the ex vivo study, en bloc resections were all achieved without perforation and muscular damage. In addition, histological evaluations could be performed in all of the resected specimens. In the in vivo study, en bloc resections were achieved without perforation and muscular damage, and uncontrollable hemorrhage did not occur during the procedures. Endoscopic submucosal dissection using a CO2 laser with a submucosal laser absorber is a feasible and safe method for the treatment of early gastric cancer.

  10. Endoscopic photodynamic therapy of tumors using gold vapor laser

    NASA Astrophysics Data System (ADS)

    Kuvshinov, Yury P.; Poddubny, Boris K.; Mironov, Andrei F.; Ponomarev, Igor V.; Shental, V. V.; Vaganov, Yu. E.; Kondratjeva, T. T.; Trofimova, E. V.

    1996-01-01

    Compact sealed-off gold vapor laser (GVL) with 2 W average power and 628 nm wavelength was used for endoscopic photodynamic therapy in 20 patients with different tumors in respiratory system and upper gastrointestinal tract. Russian-made hematoporphyrin derivative (Hpd) `Photohem' was used as a photosensitizer. It was given intravenously at a dose of 2 - 2.5 mg/kg body weight 48 hours prior to tumor illumination with 628 nm light from GVL. Intermittent irradiation with GVL was done through flexible endoscope always under local anaesthesia at a power of 200 - 400 mW/sm2 and a dose of 150 - 400 J/sm2. 80% patients showed complete or partial response depending on stage of tumor. In cases of early gastric cancer all patients had complete remission with repeated negative biopsies. No major complication occurred.

  11. Holmium:YAG laser ureteroscopic lithotripsy for ureteric calculi in children: predictive factors for complications and success.

    PubMed

    Elsheemy, Mohammed S; Maher, Ahmed; Mursi, Khaled; Shouman, Ahmed M; Shoukry, Ahmed I; Morsi, Hany A; Meshref, Alaa

    2014-08-01

    To evaluate the impact of age, stone size, location, radiolucency, extraction of stone fragments, size of ureteroscope and presence and degree of hydronephrosis on the efficacy and safety of holmium:YAG (Ho:YAG) laser lithotripsy in the ureteroscopic treatment of ureteral stones in children. Between October 2011 and May 2013, a total of 104 patients were managed using semirigid Ho:YAG ureterolithotripsy. Patient age, stone size and site, radiolucency, use of extraction devices, degree of hydronephrosis and size of ureteroscope were compared for operative time, success and complications. In all, 128 URS were done with a mean age of 4.7 years. The mean stones size was 11 mm. Success rate was 81.25 %. Causes of failure were 12.5 % access failure, 1.5 % extravasation and 4.7 % stone migration. Overall complications were 23.4 %. Failure of dilatation and extravasation were detected only in children <2 years old. Extravasation was significantly higher in smaller ureters and cases with stone size >15 mm. Stone migration was significantly higher in upper ureteric stones. Failure and complications rates in Ho:YAG ureterolithotripsy were significantly affected by younger age (<2 years), upper ureteric stones and smaller ureters but were not related to stone radiolucency or degree of hydronephrosis. Larger stones (>15 mm) were associated with increased complications. After multivariate analysis, the age of the patients remained significant predictor for failure of dilatation and stone migration, while size of the ureter was the only significant predicting factor for failure.

  12. Endoscope

    MedlinePlus

    An endoscope is a medical device with a light attached. It is used to look inside a body cavity ... sigmoidoscopy . A medical procedure using any type of endoscope is called an endoscopy . See also: Colonoscopy Cystourethroscopy ...

  13. Moderate high power 1 to 20μs and kHz Ho:YAG thin disk laser pulses for laser lithotripsy

    NASA Astrophysics Data System (ADS)

    Renz, Günther

    2015-02-01

    An acousto-optically or self-oscillation pulsed thin disk Ho:YAG laser system at 2.1 μm with an average power in the 10 W range will be presented for laser lithotripsy. In the case of cw operation the thin disk Ho:YAG is either pumped with InP diode stacks or with a thulium fiber laser which leads to a laser output power of 20 W at an optical-to-optical efficiency of 30%. For the gain switched mode of operation a modulated Tm-fiber laser is used to produce self-oscillation pulses. A favored pulse lengths for uric acid stone ablation is known to be at a few μs pulse duration which can be delivered by the thin disk laser technology. In the state of the art laser lithotripter, stone material is typically ablated with 250 to 750 μs pulses at 5 to 10 Hz and with pulse energies up to a few Joule. The ablation mechanism is performed in this case by vaporization into stone dust and fragmentation. With the thin disk laser technology, 1 to 20 μs-laser pulses with a repetition rate of a few kHz and with pulse energies in the mJ-range are available. The ablation mechanism is in this case due to a local heating of the stone material with a decomposition of the crystalline structure into calcium carbonate powder which can be handled by the human body. As a joint process to this thermal effect, imploding water vapor bubbles between the fiber end and the stone material produce sporadic shock waves which help clear out the stone dust and biological material.

  14. [Diode laser surgery in the endoscopic treatment of laryngeal paralysis].

    PubMed

    Ferri, E; García Purriños, F J

    2006-01-01

    Several surgical procedures have been proposed for the treatment of respiratory distress secondary to bilateral vocal cord paralysis. The aim of all surgical techniques used is to restore a glottic lumen sufficient to guarantee adequate breathing through the natural airway, without tracheotomy and preserving an acceptable phonatory quality. In this study we present our experience from 1998 to 2004 concerning the use of the diode contact laser for a modified Dennis-Kashima posterior endoscopic cordectomy (extended to the false homolateral chord in 3 cases and to the homolateral arytenoid vocal process in 6 cases). 18 patients (15 male, 3 female) were treated; the age range was 35-84 years. The etiology of paralysis varied: iatrogenic post-thyroidectomy and post-thoracic surgery in 5 cases (28%), post-traumatic in 2 cases (11%), secondary to a central lesion in 11 (61%). The operation was carried out with a diode contact laser (60W; 810 nm). Follow-up was 20 months. Dyspnea improved in all patients; the 9 tracheostomized patients were decannulated within 2 months after surgery. Final voice quality was subjectively good in 16 patients (88%). None of patients had any complications after surgery. In conclusion, the endoscopic posterior cordectomy performed by contact diode laser is an effective and reliable method for the treatment of dyspnea secondary to bilateral laryngeal paralysis, guaranteing a sufficient airway without impairing swallowing and maintaining acceptable voice quality.

  15. Endoscopic and interstitial Nd:YAG laser therapy to control duodenal and periampullary carcinoma

    NASA Astrophysics Data System (ADS)

    Barr, Hugh; Fowler, Aiden L.

    1996-12-01

    Duodenal and periampullary cancer present with jaundice, bleeding and obstruction. Many patients are unsuitable for radical surgery. Endoscopic palliation of jaundice can be achieved using endoscopic sphincterotomy or stent insertion. However, the problems of bleeding and obstruction can be difficult to manage. Ten patients were treated using superficial Nd:YAG laser ablation and lower power interstitial laser therapy. After initial outpatient endoscopic therapy, treatment was repeated at 4 monthly intervals to prevent recurrent symptoms. Bleeding was controlled in all patients and only one patient developed obstructive symptoms between treatment sessions. This responded to further endoscopic laser therapy. The median survival was 21 months. Laser treated patients were compared with a historical series of 22 patients treated with endoscopic sphincterotomy or stent insertion. The complication rate was less in patients treated with the laser.

  16. Single-session ureteroscopy with holmium laser lithotripsy for multiple stones.

    PubMed

    Takazawa, Ryoji; Kitayama, Sachi; Tsujii, Toshihiko

    2012-12-01

    Multiple stones are found in 20-25% of patients with urolithiasis. The stone multiplicity is a powerful adverse factor influencing the treatment outcome after shockwave lithotripsy, although guidelines for the treatment of multiple stones have not been well established yet. Herein we report our most recent experience of a single-session ureteroscopy for multiple stones. Between September 2008 and December 2011, 51 patients with multiple stones (total 146 stones) in different locations (37unilateral, 14 bilateral) underwent a total of 65 ureteroscopic procedures. Operative time, stone-free rates and complications were evaluated. Stone-free status was defined as no fragments in the ureter and the absence of >2 mm fragments in the kidney. The mean stone number per patient was 2.9 ± 1.7 and the mean stone burden (cumulative stone length) was 21.5 ± 11.6 mm. The mean number of procedures was 1.3 ± 0.6. Overall, the stone-free rate after a single session was 80% (41/51). In patients with stone burden <20 mm and ≥20 mm, stone-free rates after a single session were 92% (23/25) and 69% (18/26), respectively. Multivariate analysis showed that the stone burden and the presence of impacted stones were the factors significantly influencing the treatment outcome. Stone location did not have a strong influence on the outcome. No major intraoperative complications were identified. Our findings suggest that ureteroscopy is an efficient treatment for multiple stones. For patients with stone burden <20 mm, either unilaterally or bilaterally, a single session of ureteroscopy is a favorable treatment option with a high stone-free rate.

  17. Expanding endourology for biliary stone disease: the efficacy of intracorporeal lithotripsy on refractory biliary calculi.

    PubMed

    Sninsky, Brian C; Sehgal, Priyanka D; Hinshaw, J Louis; McDermott, John C; Nakada, Stephen Y

    2014-07-01

    We evaluated the efficacy of ureteroscopic therapy (electrohydraulic lithotripsy [EHL] and intraductal laser lithotripsy [ILL]) in patients with challenging biliary stones secondary to anatomic variations resulting from a previous surgical procedure, including liver transplantation. A retrospective chart review was performed for all patients with previous surgical alteration of the gastrointestinal (GI) tract who underwent EHL or ILL via peroral or percutaneous access for choledocholithiasis by a single surgeon at our institution from 2000 to 2012. A database containing clinical and surgical variables was created, and long-term follow-up was conducted (3-138 months; median, 99 months). Thirteen patients (51.7±20.0 years; M:F, 10:3) in whom endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangiography (PTHC), or both failed were identified. Failure of ERCP/PTHC was because of inaccessibility of the calculi in all cases. Stone clearance was achieved in 12/13 (93%) patients; 8/12 (62%) after one procedure, and 4/12 (31%) after two procedures. One patient with biliary cast syndrome needed four interventions over 9 years. Major complications were low, with only one patient with hypotension and cholangitis that resolved with 24 hours of administration of intravenous fluids and antibiotics. Both endoscopic and percutaneous lithotripsies are effective treatments for refractory biliary calculi resulting from the post-surgical GI tract. Although a staged second procedure may be necessary in patients with significant stone burden, this is significantly better than extensive open surgery.

  18. Integrated and miniaturized endoscopic devices for use during high power infrared fiber laser surgery

    NASA Astrophysics Data System (ADS)

    Wilson, Christopher Ryan

    The Thulium Fiber Laser (TFL) is currently being studied as a potential alternative to the conventional, solid-state Holmium:YAG laser (Ho:YAG) for the treatment of kidney stones. The TFL is an ideal candidate to replace the Ho:YAG for laser lithotripsy due to a higher absorption coefficient in water of the emitted wavelength, an ability to operate at high pulse rates, and a near single mode, Gaussian spatial beam profile. The higher absorption of the TFL wavelength by water translates to a decrease in ablation threshold by a factor of four. High pulse rate operation allows higher ablation rates than the Ho:YAG, thus decreasing operation time necessary to ablate the urinary stone. The Gaussian spatial beam profile allows the TFL to couple higher laser power into smaller optical fibers than those currently being used for Ho:YAG lithotripsy. This decrease in fiber diameter translates into a potential decrease in the size of ureteroscope working channel, higher saline irrigation rates for improved visibility and safety, and may also extend to a decrease in overall ureteroscope diameter. Furthermore, the improved spatial beam profile reduces the risk of damage to the input end of the fiber. Therefore, the trunk fiber, minus the distal fiber tip, may be preserved and re-used, resulting in significant cost savings. This thesis details rapid TFL lithotripsy at high pulse rates up to 500 Hz, both with and without the aid of a stone retrieval basket, in order to demonstrate the TFL's superior ablation rates over the Ho:YAG. Collateral damage testing of the TFL effect on the ureter wall and Nitinol stone baskets were conducted to ensure patient safety for future clinical use. Proximal fiber end damage testing was conducted to demonstrate fiber preservation, critical for permanent fiber integration. Optical fibers were fitted with fabricated hollow steel tips and integrated with stone retrieval baskets for testing. Ball tipped optical fibers were tested to maintain ablation

  19. Influence of Pelvicaliceal Anatomy on Stone Clearance After Flexible Ureteroscopy and Holmium Laser Lithotripsy for Large Renal Stones.

    PubMed

    Inoue, Takaaki; Murota, Takashi; Okada, Shinsuke; Hamamoto, Shuzo; Muguruma, Kouei; Kinoshita, Hidefumi; Matsuda, Tadashi

    2015-09-01

    This study was performed to evaluate the impact of pelvicaliceal anatomy on stone clearance in patients with remnant fragments in the lower pole after flexible ureteroscopy and holmium laser lithotripsy (fURSL) for renal stones >15 mm. This retrospective study included 67 patients with radiopaque residual fragments (>2 mm) in the lower pole after fURSL for large renal stones (>15 mm). The preoperative infundibular length (IL), infundibular width (IW), infundibulopelvic angle (IPA), and caliceal pelvic height (CPH) were measured using intravenous urography. Multivariate analysis was performed to determine whether any of these measurements affected stone clearance. Of the 67 patients, 55 (82.1%) were stone free (SF) 3 months after fURSL. The anatomic factors significantly favorable for an SF status were a short IL, broad IW, wide IPA, and low CPH. On multivariate analysis, the IPA had a significant influence on an SF status after fURSL (p=0.010). An IPA <30° was a negative risk factor (p=0.019). Postoperative complications occurred in nine patients (13.4%), including Clavien grade I complications in two patients (2.9%), grade II in six patients (8.9%), and grade IIIa in one patient (1.8%). Almost all complications were minor. An IPA <30° is the only negative risk factor for stone clearance after fURSL for large renal stones according to our multivariate analysis. Additional studies are required to further evaluate the characteristics of the pelvicaliceal anatomy influencing stone clearance.

  20. Study of fiber-tip damage mechanism during Ho:YAG laser lithotripsy by high-speed camera and the Schlieren method

    NASA Astrophysics Data System (ADS)

    Zhang, Jian J.; Getzan, Grant; Xuan, Jason R.; Yu, Honggang

    2015-02-01

    Fiber-tip degradation, damage, or burn back is a common problem during the ureteroscopic laser lithotripsy procedure to treat urolithiasis. Fiber-tip burn back results in reduced transmission of laser energy, which greatly reduces the efficiency of stone comminution. In some cases, the fiber-tip degradation is so severe that the damaged fiber-tip will absorb most of the laser energy, which can cause the tip portion to be overheated and melt the cladding or jacket layers of the fiber. Though it is known that the higher the energy density (which is the ratio of the laser energy fluence over the cross section area of the fiber core), the faster the fiber-tip degradation, the damage mechanism of the fibertip is still unclear. In this study, fiber-tip degradation was investigated by visualization of shockwave, cavitation/bubble dynamics, and calculus debris ejection with a high-speed camera and the Schlieren method. A commercialized, pulsed Ho:YAG laser at 2.12 um, 273/365/550-um core fibers, and calculus phantoms (Plaster of Paris, 10x10x10 mm cube) were utilized to mimic the laser lithotripsy procedure. Laser energy induced shockwave, cavitation/bubble dynamics, and stone debris ejection were recorded by a high-speed camera with a frame rate of 10,000 to 930,000 fps. The results suggested that using a high-speed camera and the Schlieren method to visualize the shockwave provided valuable information about time-dependent acoustic energy propagation and its interaction with cavitation and calculus. Detailed investigation on acoustic energy beam shaping by fiber-tip modification and interaction between shockwave, cavitation/bubble dynamics, and calculus debris ejection will be conducted as a future study.

  1. [Contribution of endoscopic laser coagulation in the treatment of multicentric sinonasal inverted papilloma. A case report].

    PubMed

    Jawhar, S S; Gassab, E; Kermani, W; Gassab, A

    2007-01-01

    To describe a new method of treatment of multicentric sinonasal inverted papilloma by laser endoscopic coagulation. We report a case of multicentric sinonasal inverted papilloma involving the nasopharynx in a 62-year-old man. The treatment was a laser diod cauterisation. The evolution was favourable without complications or recurrence after a 16 months follow-up period. Laser endoscopic coagulation seems to be an effective treatment for multicentric sinonasal inverted papilloma especially for lesions with a difficult surgical access.

  2. Flexible laser endoscope for minimally invasive photodynamic diagnosis (PDD) and therapy (PDT) toward efficient tumor removal.

    PubMed

    Hu, Y; Masamune, K

    2017-07-10

    Photodynamic diagnosis (PDD) provides valuable assistance in distinguishing tumor from the normal tissue using fluorescent colors. These colors are affected by the illumination and the photosensitizer, and PDD may be applied during operation. After the diagnosis, photodynamic therapy (PDT) could destroy tiny lesion without removing the tissue, something that considerably reduces the possibility of tumor recurrence. However, the present endoscope technologies cannot realize PDD and PDT using the same endoscope. The use of different endoscopes presents three main disadvantages. First, the intra-operation diagnosis cannot be realized unless endoscopes are the different during operation; use of different endoscopes further burdens of the surgeon and the patients. Second, it is very difficult to find the exact same area via the PDT endoscope, one that is confirmed as tumor or cancer by the PDD endoscope, when different endoscopes are used just as present applied. Third, the laser irradiation field cannot be controlled with present technologies, something that may hurt the surrounding healthy tissue or blood vessels, thus leading to serious complications. To resolve the above-mentioned problems, we propose a new flexible laser endoscope, which integrates PDD and PDT, and provides a controllable laser irradiation field for the surgeon. Experimental results proved that the resolution of both diagnosis and therapy images were five times higher than that of standard laparoscopy, the laser power density was high enough for PDT for a distance of 20 to 50 mm away from the target tumor, and the position accuracy of the presented system was half of the required errors. Moreover, the in-vitro experiments further verified the effectiveness of the laser endoscope system. Therefore, this new flexible laser endoscope is potentially suitable for future in-vivo experiments or clinical applications.

  3. Predictive value of attenuation coefficients measured as Hounsfield units on noncontrast computed tomography during flexible ureteroscopy with holmium laser lithotripsy: a single-center experience.

    PubMed

    Ito, Hiroki; Kawahara, Takashi; Terao, Hideyuki; Ogawa, Takehiko; Yao, Masahiro; Kubota, Yoshinobu; Matsuzaki, Junichi

    2012-09-01

    To assess the utility of attenuation coefficients as predictors of surgical outcome after a single flexible ureteroscopy (URS) with holmium laser lithotripsy. Many reports indicate that the efficacy of extracorporeal shockwave lithotripsy (SWL) can be predicted by the target's radiofrequency attenuation, measured as Hounsfield units (HUs) on noncontrast CT (NCCT). Studies of flexible URS, however, have not assessed the predictive value of attenuation coefficients on NCCT. Patients with renal stones who were treated by flexible URS with holmium laser lithotripsy between December 2009 and October 2011 at a single institute were retrospectively evaluated. Stone-free (SF) status was determined by kidneys-ureters-bladder (KUB) radiography at postoperative month 3. Correlations of possible predictors with SF status were analyzed using a logistic regression model. The comparison between groups with low and high HUs was examined using the Mann-Whitney U test. There were 219 eligible procedures. According to the logistic regression model, the maximum attenuation coefficient (P=0.105) and average attenuation coefficient (P=0.175) did not significantly, independently predict SF status. Fragmentation efficiency was significantly different between cases with low and high attenuation coefficients (P=0.001). In groups with less than 20.0-mm diameter stones, overall operative time (P<0.001 and P=0.001) and the time from starting fragmentation (P<0.001 and P=0.002) were significantly high in both attenuation groups. In groups with stones greater than 20.0 mm diameter, the two definitions of operative time revealed no differences between the low and high attenuation groups. The retrospective study design was the major limitation of this study. We found that both the maximum and average attenuation coefficients on NCCT are significantly related to the fragmentation efficiency. In addition, this study showed that, in patient groups with stone a burden <20.0 mm in diameter, both the

  4. High-speed photography during laser-based gall bladder stone lithotripsy

    NASA Astrophysics Data System (ADS)

    Kokaj, Jahja O.

    2001-04-01

    Shadowgraphy of gall bladder stone, which is held by a basket and immersed in a civete is performed. The exposure time is determined by the time of a N-Dye laser pulse used as a lightening source for photography. The shadowgram is projected in the objective of a camera which is connected to a microscope. The light coming from the laser, illuminates the civete collecting optical information of the stone and physical phenomena appearing above the stone. On top of the stone a tip of optical fiber is fixed, which is used for transmitting Ho:Yag laser power to the stone. Using a computer and time delay the laser pulses used for destruction and illumination are synchronized. Since the N-Dye laser pulse is pico-second range and the Ho:Yag laser pulse is in the range of micro-second, many image frames are obtained within the time of one pulse applied during the destruction. It is known that in the process of stone destruction several phenomena like plume, plasma, shock wave and bubble formation take place. However, the physical mechanism of the stone destruction is not yet completely understood. From the obtained results the above phenomena are studied which gives new information and clue for understanding some of the mentioned phenomena. The laser power which is guided by an optical fiber into the gall bladder or kidney of the human body can damage the living tissue and cause some serious health problems. For this reason the fiber needs to be oriented properly during the action of the laser power.

  5. Studies On Endoscopic Local Hyperthermia Using Nd-YAG Laser

    NASA Astrophysics Data System (ADS)

    Tsunekawa, H.; Kanemaki, N.; Furusawa, A.; Hotta, M.; Kuroiwa, A.; Nishida, M.; Mori, N.; Watanabe, Y.; Morise, K.; Iizuka, A.

    1987-03-01

    Attempting a new method of laser irradiation for depressed gastric carcinoma, using a newly developed interstitial probe and laser attenuator, we applied local hyperthermia with prolonged low watt contact irradiation. Experimental studies were performed with this probe, using BDF1 mice injected hypodermically with Lewis lung carcinoma. A laser power of 2.0 w at the tip of fiber produced the most desirable temperature curve, about 43 - 60°C at the irradiation site. Clinical applications were carried out on 15 patients with early gastric carcinoma (mainly depressed), 10 preoperative pilot cases and 5 inoperable cases. In follow-up operations and biopsies gastric carcinoma was found to have completely dis-appeared in 2 of the preoperative and 4 of the inoperable cases. In the remaining 8 preoperative cases residual traces of carcinoma were found at the margin of the laser ulcer, but not at the bottom of it. We propose that endoscopic local hyperthermia using interstitial probe and low power irradiation (2.0 W) is the safest and most suitable method of dealing with depressed carcinoma.

  6. Photoactive dye enhanced tissue ablation for endoscopic laser prostatectomy

    NASA Astrophysics Data System (ADS)

    Ahn, Minwoo; Nguyen, Trung Hau; Nguyen, Van Phuc; Oh, Junghwan; Kang, Hyun Wook

    2015-02-01

    Laser light has been widely used as a surgical tool to treat benign prostate hyperplasia with high laser power. The purpose of this study was to validate the feasibility of photoactive dye injection to enhance light absorption and eventually to facilitate tissue ablation with low laser power. The experiment was implemented on chicken breast due to minimal optical absorption Amaranth (AR), black dye (BD), hemoglobin powder (HP), and endoscopic marker (EM), were selected and tested in vitro with a customized 532-nm laser system with radiant exposure ranging from 0.9 to 3.9 J/cm2. Light absorbance and ablation threshold were measured with UV-VIS spectrometer and Probit analysis, respectively, and compared to feature the function of the injected dyes. Ablation performance with dye-injection was evaluated in light of radiant exposure, dye concentration, and number of injection. Higher light absorption by injected dyes led to lower ablation threshold as well as more efficient tissue removal in the order of AR, BD, HP, and EM. Regardless of the injected dyes, ablation efficiency principally increased with input parameter. Among the dyes, AR created the highest ablation rate of 44.2+/-0.2 μm/pulse due to higher absorbance and lower ablation threshold. Preliminary tests on canine prostate with a hydraulic injection system demonstrated that 80 W with dye injection yielded comparable ablation efficiency to 120 W with no injection, indicating 33 % reduced laser power with almost equivalent performance. In-depth comprehension on photoactive dye-enhanced tissue ablation can help accomplish efficient and safe laser treatment for BPH with low power application.

  7. Water content contribution in calculus phantom ablation during Q-switched Tm:YAG laser lithotripsy.

    PubMed

    Zhang, Jian J; Rajabhandharaks, Danop; Xuan, Jason Rongwei; Wang, Hui; Chia, Ray W J; Hasenberg, Tom; Kang, Hyun Wook

    2015-01-01

    Q-switched (QS) Tm:YAG laser ablation mechanisms on urinary calculi are still unclear to researchers. Here, dependence of water content in calculus phantom on calculus ablation performance was investigated. White gypsum cement was used as a calculus phantom model. The calculus phantoms were ablated by a total 3-J laser pulse exposure (20 mJ, 100 Hz, 1.5 s) and contact mode with N=15 sample size. Ablation volume was obtained on average 0.079, 0.122, and 0.391  mm3 in dry calculus in air, wet calculus in air, and wet calculus in-water groups, respectively. There were three proposed ablation mechanisms that could explain the effect of water content in calculus phantom on calculus ablation performance, including shock wave due to laser pulse injection and bubble collapse, spallation, and microexplosion. Increased absorption coefficient of wet calculus can cause stronger spallation process compared with that caused by dry calculus; as a result, higher calculus ablation was observed in both wet calculus in air and wet calculus in water. The test result also indicates that the shock waves generated by short laser pulse under the in-water condition have great impact on the ablation volume by Tm:YAG QS laser.

  8. Laser induced shock wave lithotripsy--biologic effects of nanosecond pulses

    SciTech Connect

    Hofmann, R.; Hartung, R.; Geissdoerfer, K.A.; Ascherl, R.; Erhardt, W.; Schmidt-Kloiber, H.; Reichel, E.

    1988-05-01

    Laser energy of a Nd-YAG laser (1064 nm. wave length, 8 nsec pulse duration) was directed against various tissue cultures and the urothelium of the ureter, bladder and kidney parenchyma in pigs. Single pulse energy was 50 to 120 mJ with a repetition rate of 20 Hz. Urothelium and kidney parenchyma were irradiated in seven pigs. Tissue samples were examined histologically and electron microscopically directly, two, four, eight and 12 days after irradiation. No macroscopic lesion could be found. Maximum energy caused a small rupture cone of 40 micron. depth. No thermic effects or necrosis resulted, so that no harm is to be expected with unintentional irradiation during laser stone disintegration.

  9. Q-switched Nd:glass-laser-induced acoustic pulses in lithotripsy

    NASA Astrophysics Data System (ADS)

    D'yakonov, G. I.; Mikhailov, B. A.; Pak, S. K.; Shcherbakov, Ivan A.; Andreev, Valeri G.; Rudenko, O. V.; Sapozhnikov, A. V.

    1991-07-01

    This paper describes preliminary experimental data of kidney stone fragmentation by the laser induced shock acoustic pulses. Acoustic pulses were produced in a thin layer of liquid as a result of absorption process of 1.06 micrometers radiation pulses. The phosphate Nd:glass laser operated in a pulse Q-switched regime with the pulse energy up to 10 J and pulse duration $OM 30 ns. The pressure induced by acoustic pulses on stones surface was reached up to 1-2 kbar in focal area, that was sufficient for stone destruction.

  10. Combined Endoscopic Optical Coherence Tomography and Laser Induced Fluorescence

    NASA Astrophysics Data System (ADS)

    Barton, Jennifer K.; Tumlinson, Alexandre R.; Utzinger, Urs

    Optical coherence tomography (OCT) and laser-induced fluorescence (LIF) are promising modalities for tissue characterization in human patients and animal models. OCT detects coherently backscattered light, whereas LIF detects fluorescence emission of endogenous biochemicals, such as reduced nicotinamide adenine dinucleotide (NADH), flavin adenine dinucleotide (FAD), collagen, and fluorescent proteins, or exogenous substances such as cyanine dyes. Given the complementary mechanisms of contrast for OCT and LIF, the combination of the two modalities could potentially provide more sensitive and specific detection of disease than either modality alone. Sample probes for both OCT and LIF can be implemented using small diameter optical fibers, suggesting a particular synergy for endoscopic applications. In this chapter, the mechanisms of contrast and diagnostic capability for both OCT and LIF are briefly examined. Evidence of complementary capability is described. Example published combined OCT-LIF systems are reviewed, one successful commercial instrument is discussed, and example applications are provided.

  11. Ureteroscopic Lithotripsy

    PubMed Central

    Bagley, Demetrius H.

    1997-01-01

    There is a wide array of endoscopic lithotriptors presently available. Each of these has its own advantages and disadvantages. No single lithotriptor is suitable for all applications and none can meet the goal of fragmenting all calculi while remaining harmless to tissue. PMID:18493444

  12. Endoscopic Nd:YAG laser treatment of rectosigmoid cancer.

    PubMed Central

    Loizou, L A; Grigg, D; Boulos, P B; Bown, S G

    1990-01-01

    Forty nine patients with rectosigmoid carcinoma considered unsuitable for surgery underwent endoscopic Nd:YAG laser treatment for palliation of symptoms and tumour eradication, if feasible. Altogether 25 (51%) of the lesions had distal margins less than 7 cm from the anus and 36 (73%) extended above the peritoneal reflection. In seven patients with tumours less than 3 cm in diameter, symptomatic improvement was achieved in all (mean follow up 16 months) and complete tumour eradication in three. In the remaining 42 patients with larger tumours (34 greater than 2/3 circumferential, mean length 5.5 cm), symptomatic improvement was achieved with repeated treatments (average 3.4) in 31 (74%) over a mean follow up of 19 weeks. Of the parameters assessed, only circumferential tumour extent proved significant in predicting functional outcome after treatment. All treatment failures (eight initial, three late) occurred in patients with extensive tumours, and only seven of these patients were considered fit for colostomy. Bowel perforation occurred in two patients (5%) but there was no treatment-related mortality. Mean stay in hospital for all laser treatments was nine days (30% were outpatient attendances). These results suggest that laser therapy may be the palliative treatment of choice in patients with rectal carcinoma unsuitable for surgery. PMID:1695161

  13. Transconjunctival dacryocystorhinostomy: scarless surgery without endoscope and laser assistance.

    PubMed

    Kaynak-Hekimhan, Pelin; Yilmaz, Omer Faruk

    2011-01-01

    To evaluate the efficacy of a novel external dacryocystorhinostomy technique with transconjunctival approach to avoid facial scarring without the use of endoscope and/or laser. In this prospective interventional case series, 25 eyes of 22 patients with epiphora due to primary nasolacrimal duct obstruction were included. Lower eyelid conjunctival inferomedial vestibular incision was used to access the lacrimal sac and nasal mucosa. Bone apertures were created with burr and rongeurs, and saccal and nasal flaps were anastomosed. Bicanalicular silicone intubation was done. Conjunctival wound edges were apposed and left unsutured. Intraoperative difficulties and complications are noted. Patients were followed up postoperatively for an average period of 11 months. Criteria for success were relief of epiphora and patency to irrigation. In 12 (48%) eyes, the surgeries were completed without complications with the formation of both the anterior and posterior flaps. Epiphora resolved in 18 of 19 eyes (94.7%) in which transconjunctival dacryocystorhinostomy could be completed. In 7 eyes (28%), only anterior flaps could be sutured. The authors needed to convert to external dacryocystorhinostomy in 6 patients (34%) during whose surgeries the nasal mucosa could not be exposed adequately via the transconjunctival route. Epiphora and failure to irrigation started in one eye (5.3%) at the postoperative fourth month and required reoperation. No complications occurred, except granuloma formation at the conjunctival incision site in 2 eyes (10.6%) and a 1-mm-long lower eyelid margin laceration in one eye (5.3%). Epiphora resolved in the remaining 6 eyes that underwent external DCR. Transconjunctival dacryocystorhinostomy, which is performed without endoscope and/or laser assistance, has a high success rate comparable to external DCR and does not leave a visible facial scar.

  14. In vitro fragmentation efficiency of holmium: yttrium-aluminum-garnet (YAG) laser lithotripsy--a comprehensive study encompassing different frequencies, pulse energies, total power levels and laser fibre diameters.

    PubMed

    Kronenberg, Peter; Traxer, Olivier

    2014-08-01

    To assess the fragmentation (ablation) efficiency of laser lithotripsy along a wide range of pulse energies, frequencies, power settings and different laser fibres, in particular to compare high- with low-frequency lithotripsy using a dynamic and innovative testing procedure free from any human interaction bias. An automated laser fragmentation testing system was developed. The unmoving laser fibres fired at the surface of an artificial stone while the stone was moved past at a constant velocity, thus creating a fissure. The lithotripter settings were 0.2-1.2 J pulse energies, 5-40 Hz frequencies, 4-20 W power levels, and 200 and 550 μm core laser fibres. Fissure width, depth, and volume were analysed and comparisons between laser settings, fibres and ablation rates were made. Low frequency-high pulse energy (LoFr-HiPE) settings were (up to six times) more ablative than high frequency-low pulse energy (HiFr-LoPE) at the same power levels (P < 0.001), as they produced deeper (P < 0.01) and wider (P < 0.001) fissures. There were linear correlations between pulse energy and fragmentation volume, fissure width, and fissure depth (all P < 0.001). Total power did not correlate with fragmentation measurements. Laser fibre diameter did not affect fragmentation volume (P = 0.81), except at very low pulse energies (0.2 J), where the large fibre was less efficient (P = 0.015). At the same total power level, LoFr-HiPE lithotripsy was most efficient. Pulse energy was the key variable that drove fragmentation efficiency. Attention must be paid to prevent the formation of time-consuming bulky debris and adapt the lithotripter settings to one's needs. As fibre diameter did not affect fragmentation efficiency, small fibres are preferable due to better scope irrigation and manoeuvrability. © 2013 The Authors. BJU International © 2013 BJU International.

  15. First experience with blind lithotripsy of ureteral calculi by ruby laser

    NASA Astrophysics Data System (ADS)

    Pupkova, Ludmila S.; Reznikov, Leonid L.; Sokolovsky, Alexander A.; Mursin, A. G.; Soms, Leonid N.; Berenberg, Vladimir A.; Polikarpov, Sergey S.; Parkhomchuk, N. A.; Voskresensky, M. A.

    1994-05-01

    For the last two years we have applied continuous dual-wavelength Nd:YAG 20 - 60 W power laser to various urologic operations. Transmission of laser irradiation via a flexible quartz fiber permitted operating at any depth of the wound. High-intensity irradiation of 1.06 mkm wavelength was effective in making thin incisions into a variety of tissues, including skin, subcutaneous fat, aponeurosis, muscles, urinary bladder wall, prostate gland, renal pelvis, renal capsule and parenchyma, and urethra. The incisions were especially effective if the contact method was used. Operational access was accomplished in 3 - 5 minutes. At the same time, hemostasis occurred in small diameter vessels. More reliable hemostasis could be achieved by means of 1.32 mkm wavelength. With the present laser device, we carried out 57 different urologic operations in our clinic. Examples of such operations include prostatectomy, pyelolithotomy, ureterolithotomy, nephrectomy, resection of renal cysts, condylomata acuminata of the urogenital organs, and papilloma of the urethra and bladder. The results suggest that a combination of these two wavelengths may prove most effective. Advantages of this approach include a decreased blood loss and decreased surgical time, asepsis, good short- and long-term results, and no complications.

  16. Proteus mirabilis viability after lithotripsy of struvite calculi

    NASA Astrophysics Data System (ADS)

    Prabakharan, Sabitha; Teichman, Joel M. H.; Spore, Scott S.; Sabanegh, Edmund; Glickman, Randolph D.; McLean, Robert J. C.

    2000-05-01

    Urinary calculi composed of struvite harbor urease-producing bacteria within the stone. The photothermal mechanism of holmium:YAG lithotripsy is uniquely different than other lithotripsy devices. We postulated that bacterial viability of struvite calculi would be less for calculi fragmented with holmium:YAG irradiation compared to other lithotripsy devices. Human calculi of known struvite composition (greater than 90% magnesium ammonium phosphate hexahydrate) were incubated with Proteus mirabilis. Calculi were fragmented with no lithotripsy (controls), or shock wave, intracorporeal ultrasonic, electrohydraulic, pneumatic, holmium:YAG or pulsed dye laser lithotripsy. After lithotripsy, stone fragments were sonicated and specimens were serially plated for 48 hours at 38 C. Bacterial counts and the rate of bacterial sterilization were compared. Median bacterial counts (colony forming units per ml) were 8 X 106 in controls and 3 X 106 in shock wave, 3 X 107 in ultrasonic, 4 X 105 in electrohydraulic, 8 X 106 in pneumatic, 5 X 104 in holmium:YAG and 1 X 106 in pulsed dye laser lithotripsy, p less than 0.001. The rate of bacterial sterilization was 50% for holmium:YAG lithotripsy treated stones versus 0% for each of the other cohorts, p less than 0.01. P. mirabilis viability is less after holmium:YAG irradiation compared to other lithotripsy devices.

  17. Stone Attenuation Values Measured by Average Hounsfield Units and Stone Volume as Predictors of Total Laser Energy Required During Ureteroscopic Lithotripsy Using Holmium:Yttrium-Aluminum-Garnet Lasers.

    PubMed

    Ofude, Mitsuo; Shima, Takashi; Yotsuyanagi, Satoshi; Ikeda, Daisuke

    2017-04-01

    To evaluate the predictors of the total laser energy (TLE) required during ureteroscopic lithotripsy (URS) using the holmium:yttrium-aluminum-garnet (Ho:YAG) laser for a single ureteral stone. We retrospectively analyzed the data of 93 URS procedures performed for a single ureteral stone in our institution from November 2011 to September 2015. We evaluated the association between TLE and preoperative clinical data, such as age, sex, body mass index, and noncontrast computed tomographic findings, including stone laterality, location, maximum diameter, volume, stone attenuation values measured using average Hounsfield units (HUs), and presence of secondary signs (severe hydronephrosis, tissue rim sign, and perinephric stranding). The mean maximum stone diameter, volume, and average HUs were 9.2 ± 3.8 mm, 283.2 ± 341.4 mm(3), and 863 ± 297, respectively. The mean TLE and operative time were 2.93 ± 3.27 kJ and 59.1 ± 28.1 minutes, respectively. Maximum stone diameter, volume, average HUs, severe hydronephrosis, and tissue rim sign were significantly correlated with TLE (Spearman's rho analysis). Stepwise multiple linear regression analysis defining stone volume, average HUs, severe hydronephrosis, and tissue rim sign as explanatory variables showed that stone volume and average HUs were significant predictors of TLE (standardized coefficients of 0.565 and 0.320, respectively; adjusted R(2) = 0.55, F = 54.7, P <.001). Stone attenuation values measured by average HUs and stone volume were strong predictors of TLE during URS using Ho:YAG laser procedures. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. [Endoscopic CO2 laser treatment for the decannulation difficulty after vertical laryngectomy].

    PubMed

    Huang, Z; Han, D; Bian, Y

    1996-01-01

    Sixteen patients with the decannulation difficulty after vertical laryngectomy were treated by endoscopic CO2 laser. The rate of decannulation was 87.5% (14/16). The curative effect was stable after 1-3 years. The causes of the decannulation difficulty included the over growth of granulation tissue, scar formation and bulky of the muscle flap. The result showed that endoscopic CO2 laser is an effective modality in the treatment of the decannulation difficulty after vertical laryngectomy.

  19. Proof-of-concept of a laser mounted endoscope for touch-less navigated procedures

    PubMed Central

    Kral, Florian; Gueler, Oezguer; Perwoeg, Martina; Bardosi, Zoltan; Puschban, Elisabeth J; Riechelmann, Herbert; Freysinger, Wolfgang

    2013-01-01

    Background and Objectives During navigated procedures a tracked pointing device is used to define target structures in the patient to visualize its position in a registered radiologic data set. When working with endoscopes in minimal invasive procedures, the target region is often difficult to reach and changing instruments is disturbing in a challenging, crucial moment of the procedure. We developed a device for touch less navigation during navigated endoscopic procedures. Materials and Methods A laser beam is delivered to the tip of a tracked endoscope angled to its axis. Thereby the position of the laser spot in the video-endoscopic images changes according to the distance between the tip of the endoscope and the target structure. A mathematical function is defined by a calibration process and is used to calculate the distance between the tip of the endoscope and the target. The tracked tip of the endoscope and the calculated distance is used to visualize the laser spot in the registered radiologic data set. Results In comparison to the tracked instrument, the touch less target definition with the laser spot yielded in an over and above error of 0.12 mm. The overall application error in this experimental setup with a plastic head was 0.61 ± 0.97 mm (95% CI −1.3 to +2.5 mm). Conclusion Integrating a laser in an endoscope and then calculating the distance to a target structure by image processing of the video endoscopic images is accurate. This technology eliminates the need for tracked probes intraoperatively and therefore allows navigation to be integrated seamlessly in clinical routine. However, it is an additional chain link in the sequence of computer-assisted surgery thus influencing the application error. Lasers Surg. Med. 45:377–382, 2013. © 2013 Wiley Periodicals, Inc. PMID:23737122

  20. Photoactive dye-enhanced tissue ablation for endoscopic laser prostatectomy.

    PubMed

    Ahn, Minwoo; Hau, Nguyen Trung; Van Phuc, Nguyen; Oh, Junghwan; Kang, Hyun Wook

    2014-11-01

    Laser light has been widely used as a surgical tool to treat benign prostate hyperplasia (BPH) over 20 years. Recently, application of high laser power up to 200 W was often reported to swiftly remove a large amount of prostatic tissue. The purpose of this study was to validate the feasibility of photoactive dye injection to enhance light absorption and eventually to facilitate tissue vaporization with low laser power. Chicken breast tissue was selected as a target tissue due to minimal optical absorption at the visible wavelength. Four biocompatible photoactive dyes, including amaranth (AR), black dye (BD), hemoglobin powder (HP), and endoscopic marker (EM), were selected and tested in vitro with a customized 532 nm laser system with radiant exposure ranging from 0.9 to 3.9 J/cm(2) . Light absorbance and ablation threshold were measured with UV-Vis spectrometer and Probit analysis, respectively, and compared to feature the function of the injected dyes. Ablation performance with dye-injection was evaluated in light of radiant exposure, dye concentration, and number of injection. Higher light absorption by injected dyes led to lower ablation threshold as well as more efficient tissue removal in the order of AR, BD, HP, and EM. Regardless of the injected dyes, ablation efficiency principally increased with radiant exposure, dye concentration, and number of injection. Among the dyes, AR created the highest ablation rate of 44.2 ± 0.2 µm/pulse due to higher absorbance and lower ablation threshold. High aspect ratios up to 7.1 ± 0.4 entailed saturation behavior in the tissue ablation injected with AR and BD, possibly resulting from plume shielding and increased scattering due to coagulation. Preliminary tests on canine prostate with a hydraulic injection system demonstrated that 80 W with dye injection yielded comparable ablation efficiency to 120 W with no injection, indicating 33% reduced laser power with almost equivalent performance. Due to

  1. [Endoscopic treatment of pielo-uretheral lithiasis with Holmium-YAG laser. Two years of experience].

    PubMed

    Palmero Martí, J L; Budía Alba, A; Pontones Moreno, J L; Broseta Rico, E; Boronat Tormo, F; Jiménez Cruz, J F

    2005-06-01

    To show the efficiency and safety of Holmium laser in the treatment of pyeloureteral lithiasis, based on our own experience since the introduction of this source of energy in our department. From January 2002 to February 2004, we have carried out 198 ureterorenoscopies using Holmium laser to treat lithiasis located in the upper urinary tract. In all cases, a previous radiological study demonstrated the stone. Follow-up, where the efficacy of the treatment was assessed, was done with a scout x-ray after 3-4 weeks. We evaluated the localization and features of the lithiasis, technical aspects, results and complications of our series. The most common localization of the lithiasis was the pelvic ureter (59%), with the number of treated cases in both the iliac and lumbar ureter being similar (16%). 70% of the lithiasis had a size between 0.5 and 1.5 cm, and 15% showed a diameter bigger than 1.5 cm. In 61.8% of cases, laser lithotripsy was carried out under spinal anaesthesia, being the average of the pulses used 2532 (confidence interval 95%), using a working power of 1 J in all cases. The overall efficacy of the procedure in terms of size and localization was 95.5%. The complication rate was scarce (2.19%). Holmium laser lithotripsy is a very effective and safe procedure since in our experience it is 95.5% efficient for pyeloureteral lithiasis treatment and has a low rate of complications.

  2. Proof-of-concept of a laser mounted endoscope for touch-less navigated procedures.

    PubMed

    Kral, Florian; Gueler, Oezguer; Perwoeg, Martina; Bardosi, Zoltan; Puschban, Elisabeth J; Riechelmann, Herbert; Freysinger, Wolfgang

    2013-08-01

    During navigated procedures a tracked pointing device is used to define target structures in the patient to visualize its position in a registered radiologic data set. When working with endoscopes in minimal invasive procedures, the target region is often difficult to reach and changing instruments is disturbing in a challenging, crucial moment of the procedure. We developed a device for touch less navigation during navigated endoscopic procedures. A laser beam is delivered to the tip of a tracked endoscope angled to its axis. Thereby the position of the laser spot in the video-endoscopic images changes according to the distance between the tip of the endoscope and the target structure. A mathematical function is defined by a calibration process and is used to calculate the distance between the tip of the endoscope and the target. The tracked tip of the endoscope and the calculated distance is used to visualize the laser spot in the registered radiologic data set. In comparison to the tracked instrument, the touch less target definition with the laser spot yielded in an over and above error of 0.12 mm. The overall application error in this experimental setup with a plastic head was 0.61 ± 0.97 mm (95% CI -1.3 to +2.5 mm). Integrating a laser in an endoscope and then calculating the distance to a target structure by image processing of the video endoscopic images is accurate. This technology eliminates the need for tracked probes intraoperatively and therefore allows navigation to be integrated seamlessly in clinical routine. However, it is an additional chain link in the sequence of computer-assisted surgery thus influencing the application error. Copyright © 2013 Wiley Periodicals, Inc.

  3. Modular flexible ureteroscopy and holmium laser lithotripsy for the treatment of renal and proximal ureteral calculi: A single-surgeon experience of 382 cases.

    PubMed

    Yan, Zejun; Xie, Guohai; Yuan, Hesheng; Cheng, Yue

    2015-10-01

    To determine the safety and efficacy of modular flexible ureteroscopy and holmium laser lithotripsy for the treatment of renal and proximal ureteral calculi, a retrospective chart review of a single surgeon's 3-year modular flexible ureteroscopy experience was performed. All of the patients were treated with modular flexible ureteroscopy and holmium laser lithotripsy by a single surgeon. Stone-free status was defined as no fragments or a single fragment ≤4 mm in diameter at the 3-month follow-up. The procedure number, operative time, stone-free rates, repeat usage of the multilumen catheter, and perioperative complications were documented. The present study included 215 male patients and 167 female patients, with an average age of 48.5±13.7 years (range, 17-84 years). The mean stone size was 11.5±4.1 mm (range, 4-28 mm), and the mean total stone burden was 17.5±5.7 mm (range 15-46 mm). A total of 305 patients (79.8%) had a stone burden ≤20 mm, and 77 patients (20.2%) had a stone burden >20 mm. The mean number of primary procedures was 1.3±0.2 (range, 1-3). The stone-free rate following the first and the second procedure was 73.4 and 86.9%, respectively. The mean postoperative hospital stay was 3.1±1.2 days (range, 2-6 days). The highest clearance rates were observed for proximal ureteral stones (100%) and renal pelvic stones (88.7%), whereas the lowest clearance rates were observed for lower calyx stones (76.7%) and multiple calyx stones (77.8%). The higher the initial stone burden, the lower the postoperative stone-free rate (≤20 vs. >20 mm; 89.8 vs. 75.3%). The overall complication rate was 8.1%. The results of the present study suggest that modular flexible ureteroscopy with holmium laser lithotripsy may be considered the primary method for the treatment of renal and proximal ureteral calculi in select patients, due to its acceptable efficacy, low morbidity, and relatively low maintenance costs.

  4. Treatment for residual stones using flexible ureteroscopy and holmium laser lithotripsy after the management of complex calculi with single-tract percutaneous nephrolithotomy.

    PubMed

    Chen, L; Sha, M-L; Li, D; Zhuo, J; Jiang, C-Y; Zhu, Y-P; Xia, S-J; Lu, J; Shao, Y

    2017-04-01

    This study validated the effectiveness and safety of the treatment for residual stones using flexible ureteroscopy (fURS) and holmium laser (0.6-1.2 J, 20-30 Hz) lithotripsy via a fiber with a 200-μm core diameter and 0.22 numerical aperture (NA) after the management of complex calculi with single-tract percutaneous nephrolithotomy (PCNL). Between January 2014 and June 2016, 27 consecutive patients with complex calculi underwent fURS and holmium laser lithotripsy after a planned single-tract PCNL. Among the 27 patients with complex calculi, 9 had full staghorn calculi, 7 had partial staghorn calculi, and 11 had multiple calculi. After the first single-tract PCNL session, the mean stone size and mean stone surface area were 18.0 ± 10.7 mm and 181.9 ± 172.2 mm(2), respectively. Treatment for residual stones with fURS and holmium laser lithotripsy was successfully completed and was performed without intraoperative complications. The mean operative time of the fURS procedure was 69.1 ± 23.6 min, and the mean hospital stay was 5.3 ± 2.4 days. The mean decrease in the hemoglobin level was 7.3 ± 6.5 g/l. After the fURS procedure, the overall stone-free rate was 88.9%. The overall postoperative complication rate was 14.8% (Clavien grade I 11.1%; Clavien grade II 3.7%). The current approach tested here combines the advantages of both PCNL and fURS and effectively manages complex calculi with a high stone-free rate (SFR) (88.9%). This approach also reduced the number of treatment sessions, the number of percutaneous access tracts, and the blood loss and potential morbidity associated with multiple tracts.

  5. State of the art extracorporeal shock wave lithotripsy

    SciTech Connect

    Kandel, L.B. ); Harrison, L.H.; McCullough, D.L. )

    1987-01-01

    This book contains 16 chapters. Some of the topics that are covered are: Extracorporeal Shock Wave Lithotripsy Development; Laser-Generated Extracorporeal Shock Wave Lithotripter; Radiation Exposure during ESWL; Caliceal Calculi; and Pediatric ESWL.

  6. Use of pneumatic lithotripsy for managing difficult CBD calculi.

    PubMed

    Farooq Qadri, Syed Javid; Khan, Muneer; Khan, Naveed

    2011-01-01

    About 7-12% of patients who harbor gallbladder calculi concomitant common bile duct (CBD) calculi are present. The treatment of gallbladder calculi has standardized in the form of laparoscopic cholecystectomy but management of CBD calculi is still evolving. Endoscopic removal of CBD calculi <2 cm in diameter is successful in 90-100% of cases but patients harboring stones >2 cm in diameter high failure rates can be seen. Traditionally, laparoscopically one can achieve success rate comparable to endoscopic surgery but large and impacted calculi may cause failures. If one uses pneumatic lithotripsy during laparoscopic management of CBD calculi one can achieve 100% stone clearance irrespective of size, degree of hardness and impaction. This study evaluates the feasibility of using pneumatic lithotripsy for CBD calculi. To our knowledge this is the 1st reported series of using pneumatic lithotripsy for CBD calculi. From June 2002 to June 2010 96 laparoscopic CBD explorations (LCBDE) were done for CBD calculi. Patients having choledocholithiasis with CBD diameter of >10 mm were taken for LCBDE while in patients with CBD diameter of <10 mm were referred for endoscopic clearance. Additionally ERCP failure cases were also subjected to LCBDE. Rigid nephroscope was used for LCBDE and usually calculi were removed by forceps only. In patients having large, hard &/or impacted calculi pneumatic lithotripsy were used for fragmentation. Out of the 96 patients in 12 (12.5%) cases pneumatic lithotripsy was used for stone fragmentation. Out of these 12 cases 5 (41.6%) were ERCP failure cases. At a mean hospital stay of 2.5 days 100% stone clearance was achieved in all cases with no perioperative complication. The present study shows how successfully pneumatic lithotripsy can be used to fragment large, hard &/or impacted CBD calculi. Pneumatic lithotripsy being user friendly easily available can reliably fragment CBD calculi in one session. Copyright © 2010 Surgical Associates

  7. A noncontact laser-guided system for endoscopic computer-assisted sinus surgery.

    PubMed

    Khan, Martin; Kosmecki, Barotsz; Reutter, Andreas; Ozbek, Christopher; Keeve, Erwin; Olze, Heidi

    2012-09-01

    The limited size of the nose leads to frequent instrument changes in navigated endonasal sinus surgery. Tracked instruments provide limited accuracy, and the pointer gives no navigation information during tissue removal. To overcome information loss, laser triangulation was integrated into navigation information. Accuracy and reliability of the laser-assisted distance-measuring system were evaluated within the distance of 0 and 20 mm. System accuracy of the laser endoscope was compared with a standard pointer using registration via bone screws and surface matching. Accuracy of the laser was 0.12 mm ± 0.12 mm with a reliability of 0.2 mm. The system accuracy of the laser endoscope was 0.59 mm ± 0.16 mm using bone screw registration and 0.64 mm ± 0.22 mm using surface matching. Additionally, laser endoscope is more accurate compared with the pointer using bone screw registration. Overall, navigation information was successfully integrated into an endoscope by laser triangulation with encouraging results.

  8. A comparative study to analyze the efficacy and safety of flexible ureteroscopy combined with holmium laser lithotripsy for residual calculi after percutaneous nephrolithotripsy

    PubMed Central

    Xu, Gang; Wen, Jiaming; Li, Zhongyi; Zhang, Zhewei; Gong, Xiuqing; Chen, Jimin; Du, Chuanjun

    2015-01-01

    A certain proportion of patients with initial Percutaneous nephrolithotripsy (PCNL) management require ancillary procedures to increase the stone-free rate. In this study, we aim to analyze the efficacy and safety of flexible ureteroscopy combined with holmium laser lithotripsy (F-UL) for treatment of residual calculi after PCNL by comparison with extracorporeal shockwave lithotripsy (SWL). Total of 96 patients with residual renal calculi (4 mm to 20 mm) after PCNL was enrolled from May 2010 to March 2013. They were randomly divided into two groups: US Group: patients were treated with F-UL; SWL Group: patients were treated with SWL. Follow-up was made one month and three months after treatment. The mean residual stone size after PCNL was 12.4 ± 4.3 mm in US group compared with 11.9 ± 4.5 in SWL group. The stone-free rate was 84.7% one month after surgical procedure in US group, this rate increased to 91.3% in the third months, while the stone-free rate in SWL group is 64.6% one month after treatment and 72.9% in the third month. For residual stone in lower calyx, the stone-free rate three month after treatment was 90.4% in US group compared to 65.2% in SWL group (P < 0.05). The overall complication rate was low in both groups, no severe complication was found. Both F-UL and SWL are safe and effective methods for residual calculi after PCNL, without severe complications. F-UL provided significantly higher stone-free rate compared with SWL, especially for low-pole calculi. PMID:26064375

  9. Endoscopic treatment of Zenker’s diverticulum by carbon dioxide laser

    PubMed Central

    Peretti, G; Piazza, C; Del Bon, F; Cocco, D; De Benedetto, L; Mangili, S

    2010-01-01

    Summary The management of Zenker’s diverticulum remains controversial, as both external and endoscopic procedures are potentially associated with post-operative complications and risks. The endoscopic approach is based on cricopharyngeal myotomy or myectomy by laser, cautery or stapling. A retrospective chart review has been made from December 1994 to April 2009 of all patients with Zenker’s diverticulum treated by endoscopic cricopharyngeal myectomy using CO2 laser at the Department of Otorhinolaryngology – Head and Neck Surgery of the University of Brescia, Italy. Of the 28 patients (19 males, 9 females; mean age, 64 years; range, 46-95) scheduled for the trans-oral procedure, 27 (96%) were endoscopically treated. Diagnosis was based on the patient’s history, flexible fiberoptic examination of the larynx, hypopharynx, and oesophagus, and videofluoroscopy with barium. Exclusion criteria included severe medical co-morbidities, impossibility to endoscopically expose the diverticulum, and small (< 2 cm) or large (> 6 cm) diverticula. The endoscopic procedure was performed using a CO2 laser to section the cricopharyngeal muscle and remove the posterior part in order to obtain partial myectomy. Major complications occurred in 2 (7%) patients. No cases of recurrent nerve paralysis, pharyngo-cutaneous fistula, neck emphysema, post-operative bleeding, mediastinitis or aspiration pneumonia were observed in the present series. A swallow survey was obtained by telephone: 85% of patients reported improved swallowing (without symptoms in 11 and with moderate dysphagia in 7). Based on the present series, endoscopic CO2 laser cricopharyngeal myectomy for Zenker’s diverticulum can be considered an effective and safe procedure, with reduced hospitalization time and complication rate. PMID:20559466

  10. Application Of Endoscopic Lasers For Operations In Gastro-Intestinal Tract

    NASA Astrophysics Data System (ADS)

    Skobelkin, O. K.; Saphronov, A. M.; Shapovalov, A. M.; Zaharov, P. I.

    1988-06-01

    We have described our experience in the application of high energy argon and Nd:YAG lasers for endoscopic surgical manipulations. Laser was used for the removal of polyps with a wide base, villi tumours in colon, for the elimination of scar strictures in colon anastomosis, for the formation of primary-delayed colon anastomosis and for the removal of timoral stenosis in esophagus and in colon. Laser therapy has certain advantages over other endoscopic manipulations: long-term and immediate results are better. One can use this therapy in combination with others (radial therapy, surgical treatment). We have worked out a classification of polyps and stenosing tumours in the digestive system to determine indications for laser endoscopy and to choose the best parameters of laser irradiation.

  11. Evaluation of endoscopic laser excision of polypropylene mesh/sutures following anti-incontinence procedures.

    PubMed

    Davis, N F; Smyth, L G; Giri, S K; Flood, H D

    2012-11-01

    We reviewed our experience with and outcome of the largest series to our knowledge of patients who underwent endoscopic laser excision of eroded polypropylene mesh or sutures as a complication of previous anti-incontinence procedures. A total of 12 female patients underwent endoscopic laser excision of suture/mesh erosions at 1 center during a 10-year period. Primary outcome variables were the requirement of additional endoscopic or open surgery to remove mesh/sutures. Secondary outcome variables were persistence of urinary symptoms, postoperative complications, continence status and requirement of additional anti-incontinence procedures. The mean interval from previous surgery to erosion was 59 months (range 7 to 144) and the duration of presenting symptoms ranged from 3 to 84 months (mean 19). Ten patients underwent endoscopic excision of the mesh/suture with the holmium:YAG laser and 2 underwent excision with the thulium laser. Mean operative duration was 19 minutes (range 10 to 25) and followup was 65.5 months (range 6 to 134). Postoperatively 6 patients remain asymptomatic and 2 required a rectus fascial sling for recurrent stress urinary incontinence. Four patients underwent a second endoscopic excision due to minor persistence of erosion. Only 1 patient ultimately required open cystotomy to remove the eroded biomaterial. No intraoperative complications were recorded and all patients are currently asymptomatic. Endoscopic laser excision is an acceptable first line approach for the management of eroded biomaterials due to its high long-term success rate and minimally invasive nature. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  12. Increased Risk of New-Onset Hypertension After Shock Wave Lithotripsy in Urolithiasis: A Nationwide Cohort Study.

    PubMed

    Huang, Shi-Wei; Tsai, Chung-You; Wang, Jui; Pu, Yeong-Shiau; Chen, Pei-Chun; Huang, Chao-Yuan; Chien, Kuo-Liong

    2017-10-01

    Although shock wave lithotripsy is minimally invasive, earlier studies argued that it may increase patients' subsequent risk of hypertension and diabetes mellitus. This study evaluated the association between shock wave lithotripsy and new-onset hypertension or diabetes mellitus. The Taiwanese National Health Insurance Research Database was used to identify 20 219 patients aged 18 to 65 years who underwent the first stone surgical treatment (shock wave lithotripsy or ureterorenoscopic lithotripsy) between January 1999 and December 2011. A Cox proportional model was applied to evaluate associations. Time-varying Cox models were applied to evaluate the association between the number of shock wave lithotripsy sessions and the incidence of hypertension or diabetes mellitus. After a median follow-up of 74.9 and 82.6 months, 2028 and 688 patients developed hypertension in the shock wave lithotripsy and ureterorenoscopic lithotripsy groups, respectively. Patients who underwent shock wave lithotripsy had a higher probability of developing hypertension than patients who underwent ureterorenoscopic lithotripsy, with a hazard ratio of 1.20 (95% confidence interval, 1.10-1.31) after adjusting for covariates. The risk increased as the number of shock wave lithotripsy sessions increased. However, the diabetes mellitus risk was similar in the shock wave lithotripsy and ureterorenoscopic lithotripsy groups. Furthermore, the hazard ratio did not increase as the number of shock wave lithotripsy sessions increased. Shock wave lithotripsy consistently increased the incidence of hypertension on long-term follow-up. Therefore, alternatives to urolithiasis treatment (eg, endoscopic surgery or medical expulsion therapy) could avoid the hypertension risk. Furthermore, avoiding multiple sessions of shock wave lithotripsy could also evade the hypertension risk. © 2017 American Heart Association, Inc.

  13. Bacteria Inactivation During Lithotripsy

    NASA Astrophysics Data System (ADS)

    del Sol Quintero, María; Mora, Ulises; Gutiérrez, Jorge; Mues, Enrique; Castaño, Eduardo; Fernández, Francisco; Loske, Achim M.

    2006-09-01

    The influence of extracorporeal and intracorporeal lithotripsy on the viability of bacteria contained inside artificial kidney stones was investigated in vitro. Two different bacteria were exposed to the action of one extracorporeal shock wave generator and four intracorporeal lithotripters.

  14. Lithotripsy procedure (image)

    MedlinePlus

    Extracorporeal shock wave lithotripsy (ESWL) is a procedure used to shatter simple stones in the kidney or upper urinary tract. Ultrasonic waves are passed through the body until they strike the dense stones. Pulses of ...

  15. Clearance of refractory bile duct stones with extracorporeal shockwave lithotripsy

    PubMed Central

    Ellis, R; Jenkins, A; Thompson, R; Ede, R

    2000-01-01

    BACKGROUND—Extracorporeal shockwave lithotripsy (ESWL) has been used since the mid-1980s to fragment bile duct stones which cannot be removed endoscopically. Early machines required general anaesthesia and immersion in a waterbath.
AIMS—To investigate the effectiveness of the third generation Storz Modulith SL20 lithotriptor in fragmenting bile duct stones that could not be cleared by mechanical lithotripsy.
METHODS—Eighty three patients with retained bile duct stones were treated. All patients received intravenous benzodiazepine sedation and pethidine analgesia. Stones were targeted by fluoroscopy following injection of contrast via a nasobiliary drain or T tube. Residual fragments were cleared at endoscopic retrograde cholangiopancreatography.
RESULTS—Complete stone clearance was achieved in 69 (83%) patients and in 18 of 24 patients (75%) who required more than one ESWL treatment. Stone clearance was achieved in all nine patients (100%) with intrahepatic stones and also in nine patients (100%) referred following surgical exploration of the bile duct. Complications included six cases of cholangitis and one perinephric haematoma which resolved spontaneously.
CONCLUSION—Using the Storz Modulith, 83% of refractory bile duct calculi were cleared with a low rate of complications. These results confirm that ESWL is an excellent alternative to surgery in those patients in whom endoscopic techniques have failed.


Keywords: lithotripsy; bile duct calculi; extracorporeal lithotripsy PMID:11034593

  16. Endoscopic management of radio-opaque bile duct stones.

    PubMed

    Bhandari, Suryaprakash; Maydeo, Amit

    2015-11-01

    Majority of the bile duct stones (BDS) are radiolucent (RL) and are amenable to conventional endoscopic extraction techniques. There is no publication that specifically discusses the optimal management of radio-opaque (RO) BDS and makes a distinction from the strategy followed for RL BDS. Data of patients with BDS managed endoscopically from January 2009 till June 2015 were retrospectively reviewed. Diagnosis of RO stone was established during initial fluoroscopy, just prior to obtaining a cholangiogram. Endoscopic retrograde cholangiopancreatography (ERCP) was done using therapeutic duodenoscope. Stone extraction was attempted initially using conventional techniques. Balloon sphincteroplasty or mechanical lithotripsy (ML) or both were done if conventional techniques failed. Cholangioscopy-guided intracorporeal holmium laser lithotripsy (LL) was done when all the above techniques failed. Fifteen patients were found to have RO stones in the bile duct during the study period. ERCP was successful in all patients. Discrepancy of the stone size in relation to the lower CBD diameter was seen in eight patients (53.34 %). Stone extraction with conventional techniques was successful in 2/15 patients (13 %). Successful controlled radial expansion (CRE) balloon sphincteroplasty/ML was possible in 5/15 patients (33 %). Cholangioscopy guided LL was done in eight patients (53.34 %) with successful pulverization of RO BDS (100 %). RO bile duct stones provide unique challenges for endoscopic management with success of conventional techniques in only about half of them (46 %). RO stones detected on fluoroscopy are extremely hard and difficult to crush with lithotripsy basket probably due to high calcium content. Cholangioscopy guided LL provides an excellent alternative management strategy.

  17. Endoscopic laser-assisted dacryocistorhinostomy DCR with the placement of a customised silicone and Teflon bicanalicular stent Endoscopic laser-assisted dacryocystorhinostomy (DCR).

    PubMed

    D'Ecclesia, A; Cocchi, R F; Giordano, F; Mazzilli, E; Longo, C; Laborante, A

    We present our experience in endoscopic laser assisted dacryocystorhinostomy (DCR) analyzing the results obtained with a new technique that involves placing bicanalicolar silicone stent more Teflon tube, in combination with paraseptal silastic sheet. In our study 49 of 57 patients (85%) at a mean follow up of at least 12 months have not reported epiphora or more episodes of acute dacryocystitis. 49 out of the 57 patients (85%) in our group reported no additional epiphora or episodes of acute dacryocystitis. Endoscopic DCR is currently the gold standard for sac and post-sac stenosis given the minimal invasiveness of the procedure and the long-term results that appear comparable to those obtained with extrinsic DCR. The principal problem is cicatricial stenosis that can occlude the stoma over time.

  18. Correction method of bending loss in the hollow optical fiber for endoscopic submucosal dissection using carbon dioxide laser

    NASA Astrophysics Data System (ADS)

    Kusakari, Daisuke; Hazama, Hisanao; Awazu, Kunio

    2015-03-01

    Endoscopic submucosal dissection using carbon dioxide laser is a promising treatment of early digestive cancer because it can avoid the risk of perforation. Although a hollow optical fiber transmitting mid-infrared light has been used, it was observed that the irradiation effect was influenced by bending a gastrointestinal gastrointestinal endoscope due to the change in transmittance by the bending loss. Therefore, we quantitatively evaluated the change in the irradiation effect by bending the hollow optical fiber in the gastrointestinal endoscope and proposed a correction method to stabilize the irradiation effect. First, the relationship between the irradiated laser energy density and the incision depth for porcine stomach was measured by bending the head of the gastrointestinal endoscope. Next, the relationship between the bending angle of the head of the gastrointestinal endoscope and the temperature rise of the hollow optical fiber in the head of the gastrointestinal endoscope was measured during the laser irradiation. As a result, the laser energy density and the incision depth decreased as the bending angle increased, and linear correlation between the laser energy density and the incision depth was observed. It was found that the bending angle can be estimated by the ratio of the setting laser power to time derivative of the temporal profile of the temperature of the hollow optical fiber. In conclusion, it is suggested that the correction of the laser energy density and stabilization of the incision capability is possible by measuring the temporal profile of the temperature of the hollow optical fiber.

  19. Combined retrograde flexible ureteroscopic lithotripsy with holmium YAG laser for renal calculi associated with ipsilateral ureteral stones.

    PubMed

    Cocuzza, Marcello; Colombo, Jose R; Ganpule, Arvind; Turna, Burak; Cocuzza, Antonio; Dhawan, Divyar; Santos, Bruno; Mazzucchi, Eduardo; Srougi, Miguel; Desai, Mahesh; Desai, Mihir

    2009-02-01

    The purpose of this study was to evaluate the effectiveness of combined ureteroscopic holmium YAG lithotripsy for renal calculi associated with ipsilateral ureteral stones. Between August 2002 and March 2007, retrograde flexible ureteroscopic stone treatment was attempted in 351 cases. Indication for treatment was concurrent symptomatic ureteral stones in 63 patients (group I). Additional operative time and perioperative complication rates were compared to a group of 39 patients submitted to ureteroscopic treatment for ureteral calculi exclusively (group II). Mean ureteral stone size was 8.0 +/- 2.6 mm and 8.1 +/- 3.4 mm for groups I and II, respectively. Mean operative time for group I was 67.9 +/- 29.5 minutes and for group 2 was 49.3 +/- 13.2 minutes (p < 0.001). Flexible ureteroscopic therapy for renal calculi increased 18 minutes in the mean operative time. The overall complication rate was 3.1% and 2.5% for groups I and II, respectively (p = 0.87). Mean renal stone size was 10.7 +/- 6.4 mm, overall stone free rate in group I was 81%. However, considering only patients with renal stones smaller than 15 mm, the stone free rate was 88%. Successful treatment occurred in 81% of patients presenting lower pole stones, but only 76% of patients with multiple renal stones became stone free. As expected, stone free rate showed a significant negative correlation with renal stone size (p = 0.03; r = -0.36). Logistic regression model indicated an independent association of renal stones smaller than 15 mm and stone free rate (OR = 13.5; p = 0.01). Combined ureteroscopic treatment for ureteral and ipsilateral renal calculi is a safe and attractive option for patients presenting for symptomatic ureteral stone and ipsilateral renal calculi smaller than 15 mm.

  20. Extracorporeal piezoelectric lithotripsy for complicated bile duct stones.

    PubMed

    Weber, J; Adamek, H E; Riemann, J F

    1991-02-01

    Today, common bile duct stones are extracted endoscopically. After endoscopic sphincterotomy, nearly 90% of all stones can be removed with a Dormia basket or a mechanical lithotripter. Problems are encountered if there are larger stones or a duct stenosis. New conservative therapies do serve as an alternative to surgical intervention for those few patients in whom endoscopic measures have failed. Stone fragmentation can be achieved by extracorporeal shock wave lithotripsy, and remaining fragments can be removed endoscopically. So far, authors of most reports on the successful disintegration of common bile duct stones used the Dornier lithotripter. Stone localization is thus achieved with x-rays, and the shock waves are generated by an underwater spark discharge. We report on our experiences and results with extracorporeal piezoelectric shock wave lithotripsy (EPL) in 19 patients with complicated bile duct stones. With this lithotripter, stones are visualized by ultrasound, and shock waves are produced by a piezoelectric acoustic generator. Fragmentation was achieved in 84.2%, and complete stone removal in 78.9%. These results show that piezoelectric lithotripsy is also a useful method for the treatment of complicated bile duct stones, as has already been proved for the electrohydraulic- and electromagnetic-generated shock waves systems. However, the renunciation of general anesthesia and the need for analgesia or sedation in only 25% of the treatments render this lithotripter system attractive, especially for elderly and frail patients.

  1. Experimental Study Of Laser Induced Byperthermia (Laserthermia); Comparative Histological Study Between Prototype System And New System, And Clinical Applications Of Endoscopic Laserthermia

    NASA Astrophysics Data System (ADS)

    Aoki, Jun; Suzuki, Sohtaro; Shilina, Yasubuilmi; Miwa, Takeshi; Daikuzono, Norio; Joffe, Stephen N.

    1988-06-01

    Since 19843 we have been studying endoscopic laser induced hyperthermia (laserthermia) with SLT frosted contact probe and low power Nd-YAG laser irradiation under 5 watts" The endoscopic laserthermia have been reported endoscopically such as tumor reduction3. In this paper, we would like to discuss the comparative histological studies between the first prototype laserthermia system. with Medilas(M..B.B.) Nd-YAG laser and the new laser-thermia system with SLT Contact Laser on canine stomach, and report clinical application of endoscopic laserthermia to the gastric cancers. The computer controlled laserthermia will be possible to apply for the treatment of the malignant tumor in the gastrointestinal (GI) tract.

  2. Experimental Studies Of Endoscopic Local Hyperthermia With Contact Nd-YAG Laser

    NASA Astrophysics Data System (ADS)

    Suzuki, Sohtaro; Aoki, Jun; Shiina, Yasubumi; Miwa, Takeshi; Daikuzono, Norio; Joffe, Stephen N.

    1987-03-01

    We have been studying experimentally and clinically to evaluate the histological effects and safety of the therapeutic Nd-YAG laser endoscopy by the contact method with new ceramic endoprobes comparing wit Li those by the non-contact method with single quartz fiber. In this paper, we would like to discuss possibilities of clinical application of endoscopic local hyperthermia using Nd-YAG laser (Laserthermia) with computer control system. Newly developed computer controlled Laserthermia may possible to apply for the treatment of the malignant tumor in the gastrointestinal (GI) tract.

  3. Towards endoscopic ultrafast laser microsurgery of vocal folds

    NASA Astrophysics Data System (ADS)

    Hoy, Christopher L.; Everett, W. Neil; Yildirim, Murat; Kobler, James; Zeitels, Steven M.; Ben-Yakar, Adela

    2012-03-01

    Vocal fold scarring is a predominant cause of voice disorders yet lacks a reliable treatment method. The injection of soft biomaterials to improve mechanical compliance of the vocal folds has emerged as a promising treatment. Here, we study the use of precise femtosecond laser microsurgery to ablate subsurface voids, with a goal of eventually creating a plane in dense subepithelial scar tissue into which biomaterials can be injected for their improved localization. Specifically, we demonstrate the ablation of small subepithelial voids in porcine vocal fold tissue up to 120 µm below the surface such that larger voids in the active area of vocal fold mucosa (~3×10 mm2) can eventually be ablated in about 3 min. We use sub-µJ, 776-nm pulses from a compact femtosecond fiber laser system operating at a 500-kHz repetition rate. The use of relatively high repetition rates, with a small number of overlapping pulses, is critical to achieving ablation in a very short time while still avoiding significant heat deposition. Additionally, we use the same laser for nonlinear optical imaging to provide visual feedback of tissue structure and to confirm successful ablation. The ablation parameters, including pulse duration, pulse energy, spot size, and scanning speed, are comparable to the specifications in our recently developed miniaturized femtosecond laser surgery probes, illustrating the feasibility of developing an ultrafast laser surgical instrument.

  4. Current state of clinical lithotripsy

    NASA Astrophysics Data System (ADS)

    Lingeman, James E.

    2003-10-01

    Extracorporeal shock wave lithotripsy (ESWL) has revolutionized the treatment of urolithiasis. Because of the clinical success of the original lithotriptor, the Dornier HM3, numerous manufacturers introduced different approaches to lithotripsy based on empiricism rather than an understanding of the fundamental mechanisms of this new technology. Our understanding of shock wave physics and the physiologic effects of shock waves has progressed greatly over the last decade resulting in insights that hopefully will be reflected favorably in future lithotriptor designs and lithotripsy techniques.

  5. Experimental Study And Clinical Application Of New Ceramic Endoprobe With Nd-YAG Laser; Endoscopic Hemostasis, Pyloroplasty And Cutting Biopsy

    NASA Astrophysics Data System (ADS)

    Aoki, Jun; Suzuki, Sohtaro; Shiina, Yasubumi; Miwa, Takeshi; Daikuzono, Norio; Joffe, Stephen N.

    1987-03-01

    We have been studying endoscopic Nd-YAG laser therapies since 1979. In consequence, advantages of the contact method by using ceramic endoprobes were revealed123. Various endoprobes were developed by our studies, and the experimental studies and clinical applications of ceramic frosted probe and chisel probe with Nd-YAG laser were studied. Frosted probe was able to thrombose in the artery of the canine gastric submucosal layer by Nd-YAG laser irra-diation, and was applied to endoscopic hemostasis. Chisel probe was able to cut canine gastric mucosa at the power of 20watts and duration of 2.Osec. with Nd-YAG laser, and was applied to endoscopic pyloroplasty and cutting complete biopsy of submucosal tumor.

  6. Diode laser endoscopic cyclophotocoagulation in the normal equine eye.

    PubMed

    Harrington, Jay T; McMullen, Richard J; Cullen, John M; Campbell, Nigel B; Gilger, Brian C

    2013-03-01

    To determine the clinical and histologic effects of diode endoscopic cyclophotocoagulation (ECP) in the phakic equine eye. Phase I: 10 equine cadaver eyes. Phase II: four normal adult horses. Phase I: ECP probe angle of reach (AR) was determined. Multiple ECP energy levels: 0.75, 0.90, 1.05, 1.20, 1.35, 1.50 J, and the resulting visible and histologic ciliary process changes were evaluated. Phase II: Ocular quadrants were treated with ECP at 0.90, 1.14, 1.38 J, and a control. The contralateral eye underwent a sham operation. Tissue changes (clinical and histologic) were evaluated. Phase I: Mean combined AR was 162 ± 29 degrees. Mean visible tissue scores: 2.60 ± 0.58 (0.75 J) to 5.04 ± 0.30 (1.50 J) from possible total of 6. Tissue 'popping' was observed at 1.50 J. Histologic ciliary tissue damage was present at all settings. Phase II: Mean visible tissue scores: 2.90 ± 0.48 (0.90 J), 3.61 ± 0.57 (1.14 J), and 4.52 ± 0.56 (1.38 J). Tissue 'popping' was observed at 1.38 J. Histologic ciliary tissue damage was present at all settings. Clinical effects included acute inflammation, intraocular pressure reduction, cataract formation, corneal edema, corneal ulceration, and postoperative ocular hypertension. Diode ECP between 0.90 and 1.14 J is a potential treatment option for glaucoma in horses based on visible tissue effects and target ciliary epithelium damage. Iatrogenic cataract development may limit the use of an anterior chamber approach in phakic horses. Supported in part by an ACVO VAF grant. © 2012 American College of Veterinary Ophthalmologists.

  7. An endoscopic laser Doppler flowmetry of a gastroduodenal mucosa at bleeding ulcer

    NASA Astrophysics Data System (ADS)

    Shapkin, U. G.; Kapralov, C. V.; Gogolev, A. A.; Lychagov, V. V.; Tuchin, V. V.

    2006-08-01

    One of the important problems of a bleeding gastroduodenal ulcer surgery is a prognosis of the recurrent hemorrhage and appraisal of endoscopic hemostasis quality. Endoscopic Laser Doppler Flowmetry of a mucous coat of stomach and a duodenum was made on 34 patients for the purpose of investigation of features of microcirculation. Analogous researches are made on 30 patients with a peptic ulcer and on 28 practically healthy people. Analysis of LDF-grams has shown certain differences in regional microcirculations in stomach and duodenal at normal and at a pathology. Increase of regional perfusion in periulcerose zone with its pathology disbalance can serve as a criterion for activities of an alteration processes in gastroduodenal ulcer defining the risk of possible hemorrhage.

  8. Endoscopic laser range scanner for minimally invasive, image guided kidney surgery

    NASA Astrophysics Data System (ADS)

    Friets, Eric; Bieszczad, Jerry; Kynor, David; Norris, James; Davis, Brynmor; Allen, Lindsay; Chambers, Robert; Wolf, Jacob; Glisson, Courtenay; Herrell, S. Duke; Galloway, Robert L.

    2013-03-01

    Image guided surgery (IGS) has led to significant advances in surgical procedures and outcomes. Endoscopic IGS is hindered, however, by the lack of suitable intraoperative scanning technology for registration with preoperative tomographic image data. This paper describes implementation of an endoscopic laser range scanner (eLRS) system for accurate, intraoperative mapping of the kidney surface, registration of the measured kidney surface with preoperative tomographic images, and interactive image-based surgical guidance for subsurface lesion targeting. The eLRS comprises a standard stereo endoscope coupled to a steerable laser, which scans a laser fan beam across the kidney surface, and a high-speed color camera, which records the laser-illuminated pixel locations on the kidney. Through calibrated triangulation, a dense set of 3-D surface coordinates are determined. At maximum resolution, the eLRS acquires over 300,000 surface points in less than 15 seconds. Lower resolution scans of 27,500 points are acquired in one second. Measurement accuracy of the eLRS, determined through scanning of reference planar and spherical phantoms, is estimated to be 0.38 +/- 0.27 mm at a range of 2 to 6 cm. Registration of the scanned kidney surface with preoperative image data is achieved using a modified iterative closest point algorithm. Surgical guidance is provided through graphical overlay of the boundaries of subsurface lesions, vasculature, ducts, and other renal structures labeled in the CT or MR images, onto the eLRS camera image. Depth to these subsurface targets is also displayed. Proof of clinical feasibility has been established in an explanted perfused porcine kidney experiment.

  9. Endoscopic laser-induced steam generator: a new method of treatment for early gastric cancer

    NASA Astrophysics Data System (ADS)

    Hayashi, Takuya; Arai, Tsunenori; Tajiri, Hisao; Nogami, Yashiroh; Hino, Kunihiko; Kikuchi, Makoto

    1996-05-01

    The minimum invasive endoscopic treatment for early gastric cancer has been popular in Japan. The endoscopic mucosal resection and laser coagulation by Nd:YAG laser irradiation has been the popular treatment method in this field. However, the submucosal cancer has not been successfully treated by these methods. To treat the submucosal cancer endoscopically, we developed a new coagulation therapy using hot steam generated by Nd:YAG laser. The steam of which temperature was over 10 deg. in Celsius was generated by the laser power of 30 W with 5 ml/min. of saline. The steam was emitted to canine gastric wall under laparotomy or endoscopy for 50 s respectively. Follow up endoscopy was performed on 3, 7, 14, 28 days after the treatment. Histological examination was studied on 7, 28 days, and just after the emission. In the acute observation, the submucosal layer was totally coagulated. On the 7th day, ulceration with white coat was seen. The mucosal defect, submucosal coagulation, and marked edema without muscle degeneration were found by the histological study. On the 14th day, the ulcer advanced in the scar stage. On the 28th day, it completely healed into white scar with mucosal regeneration and mucosal muscle thickening. We could obtain reproducible coagulation up to deep submucosal layer with large area in a short operation time. Moreover there were no degeneration of proper muscle. This treatment effectiveness could be easily controlled by the steam temperature and emission duration. We think that this method can be applied to early gastric cancer including the submucosal cancer, in particular poor risk case for operation. Further study should be done to apply this method to clinical therapy.

  10. Angular effect of optical fiber movement on endoscopic laser prostatectomy.

    PubMed

    Rajabhandharaks, Danop; Kang, Hyun Wook; Oh, Junghwan

    2012-10-01

    The optimal fiber manipulation during laser prostatectomy has been highlighted as a critical element to achieve desirable clinical outcomes. However, scientific understanding of the physical interplay between fiber movement and ablative tissue response is still lacking. The objective of this study was to quantitatively investigate the effect of angular movement of an optical fiber on tissue ablation performance. Porcine kidney was employed as a tissue model in vitro. A 180 W 532 nm surgical laser with 750 µm side-firing fibers was utilized to mimic clinical laser prostatectomy. The effect of fiber manipulation parameters on the tissue such as irradiance, number of overlapping pulses (OP), and beam path length (BPL) was assessed at various fiber sweeping (rotational) angles ranging from 0° to 120°. Morphological properties of the post-irradiated tissue were also evaluated in light of ablation depth, coagulative necrosis, and volumetric ablation density (VAD). As sweeping angle (SA) increased, both laser irradiance and number of OP decreased but BPL increased. Ablation depth was maximized (5.4 ± 1.0 mm) at SAs less than 30° but decreased at higher SAs. The SAs of 15° and 30° demonstrated the minimal thickness of denaturized tissue (0.74 ± 0.14 mm) and VAD (total laser energy/ablation volume (AV) ≈ 4.6 ± 0.46 J/mm(3) ). Decreasing depth and increasing tissue coagulation associated with increasing SA resulted from substantial reduction in both beam irradiance and number of OP, eventually impeding ablation process. Excessive tissue denaturation also occurred when no rotational motion was applied to the fiber possibly due to plume shielding. Inefficient tissue ablation could lead to adverse post-operative complications due to unwanted thermal injury to peripheral tissue. A SA of 30° was found to be desirable for effective tissue ablation, and further clinical investigations will validate the current findings. Copyright © 2012

  11. [Endoscopic laser surgery in combined nasopharyngeal and middle ear pathology in children with conductive hypoacusis].

    PubMed

    Kotov, R V; Polunin, M M; Garashchenko, T I; Rakhmanova, I V

    2007-01-01

    Endoscopic laser surgery on lymphoid structures of the nasopharynx near the pharyngeal opening of the auditory tube was made with Lazon-10P laser in 67 children aged 3 to 14 years with documented exudative otitis media (EOM). All the children had conductive hypoacusis. Children who had tympanogram of type B and in whom otoscopy detected exudate behind the tympanic membrane were subjected to one-stage laser tympanostomy in the anteroinferior quadrant of the tympanic membrane followed by transtympanic drug introduction into the tympanic cavity. Tympanostoma closed spontaneously 3 weeks later. Normal hearing recovered in all the children. Diagnostic endoscopy of the nasopharynx can reveal causes underlying dysfunction of the auditory tube. The results demonstrate high efficacy of the methods allowing elimination of mechanical occlusion of the auditory tube in the region of its pharyngeal opening with one-stage intervention on the middle ear.

  12. Innovations in Lithotripsy Technology

    NASA Astrophysics Data System (ADS)

    Zhong, Pei

    2007-04-01

    The introduction of shock wave lithotripsy (SWL) in the early 1980's revolutionized the surgical management for kidney stone disease. Since then, although numerous 2nd- and 3rd-generation lithotripters have been developed using various means for shock wave generation, focusing, patient coupling and stone localization, the technical improvements in these devices were largely made based on practical concerns for user convenience and multifunctionality of the system rather than a clear understanding of the working principles of SWL. In this paper, the fundamental mechanisms of stone comminution and tissue injury in SWL revealed by basic studies in the past two decades are first reviewed. This is followed by a summary of the innovations in SWL technology developed in recent years that have been demonstrated to provide improved stone comminution with concomitantly reduced tissue injury both in vitro using phantom systems and in vivo in animal models. Furthermore, the role of treatment strategy in determining the overall outcome of clinical lithotripsy is emphasized, and future prospects for lithotripsy research and technological innovations are discussed.

  13. Endoscopic laser speckle contrast imaging system using a fibre image guide

    NASA Astrophysics Data System (ADS)

    Song, Lipei; Elson, Daniel

    2011-03-01

    There are several challenges when fibre image guides (FIG) are used for endoscopic speckle acquisition: cross talk between fibre cores, FIG fixed pattern noise, the small probe diameter and low sensitivity and resolution due to the decreased number of speckles and their low transmission through the FIG. In this paper, an endoscopic laser speckle contrast analysis system (ELASCA) based on a leached fibre image guide (LFIG) is presented. Different methods of acquiring LASCA images through LFIGs were investigated including the effect of changing the number of speckles per fibre, defocusing the FIG image onto the CCD and processing speckle images with masks and Butterworth filters to deal with the LFIG fixed pattern and noise from the cladding. The experimental results based on a phantom consisting of intralipid suspension pumped at varying speed showed that this system could detect speed changes and that in the case of multiple speckles per fibre the Nyquist frequency criterion need not be applied since the speckle may be transferred through the fibres to some extent. In contrast to the previously reported ELASCA results, this system can both give a map of the observed area and the temporal change in flow. An additional benefit is the small size of the LFIG, which is compatible with current endoscopic instrument channels and may allow additional surgical applications.

  14. Safety and feasibility of day case ureteroscopy and laser lithotripsy (URSL) in patients with a solitary kidney

    PubMed Central

    Ghosh, Anngona

    2016-01-01

    Introduction The management of nephrolithiasis in patients with a solitary kidney poses a treatment challenge. The study aimed to evaluate the outcomes of ureteroscopy and laser stone fragmentation (URSL) for renal stones in these patients treated in our university teaching hospital. Material and methods Between July 2012 and December 2014, seventeen cases of URSL for stones in a solitary kidney were reviewed. Patient demographics, stone dimensions, perioperative and post-operative outcomes were recorded in a prospectively maintained database. Serum creatinine levels pre-procedure and at follow-up were also compared. Results Seventeen cases of URSL were conducted with a mean age of 52.9 ±19.9 years. 8 of the 17 (47%) patients had stones in multiple locations and 13 (76%) were in the lower pole. The mean ± SD stone size and BMI were 13.0 ±8.9 mm and 31.6 ±5.8 kg/m2, respectively. The stone free rate (SFR) was 82.5%. Fourteen (82.5%) patients were discharged the same day and 16 cases (94%) were discharged within 24 hours. For patients with deranged pre-operative serum creatinine, the mean serum creatinine level improved from 131.2 ±68.3 µmol/L pre-URSL to 106.5 ±36.7 µmol/L at follow-up. There was one Clavien grade II complication with a patient requiring additional antibiotics for post-operative urinary tract infection. There were no other major or minor complications. Conclusions Day case ureteroscopy for stone disease in a solitary kidney is safe and feasible with a low complication rate and an overall improvement in renal function. PMID:27123333

  15. Low cost and compact nonlinear (SHG/TPE) laser scanning endoscope for bio-medical application

    NASA Astrophysics Data System (ADS)

    Liu, Jiayun; Lim, Ken Choong; Li, Hao; Seck, Hon Luen; Yu, Xia; Kok, Shaw Wei; Zhang, Ying

    2015-03-01

    Two-photon fluorescence (TPE) and second harmonic generation (SHG) can been used to extract biological information from tissues at the molecular level, which is blind to traditional microscopes. Through these two image contrast mechanisms, a nonlinear laser scanning endoscope (NLSE) is able to image tissue cells and the extra cellular matrix (ECM) through a special fiber and miniaturized scanner without the requirement of poisonous chemical staining. Therefore, NLSE reserves high potential for in-vivo pathological study and disease diagnosis. However, the high cost and bulky size of a NLSE system has become one of the major issues preventing this technology from practical clinical operation. In this paper, we report a fiber laser based multi-modality NLSE system with compact size and low cost, ideal for in-vivo applications in clinical environments. The demonstration of the developed NLSE nonlinear imaging capability on different bio-structures in liver, retina and skin are also presented.

  16. Automatic Tracking Algorithm in Coaxial Near-Infrared Laser Ablation Endoscope for Fetus Surgery

    NASA Astrophysics Data System (ADS)

    Hu, Yan; Yamanaka, Noriaki; Masamune, Ken

    2014-07-01

    This article reports a stable vessel object tracking method for the treatment of twin-to-twin transfusion syndrome based on our previous 2 DOF endoscope. During the treatment of laser coagulation, it is necessary to focus on the exact position of the target object, however it moves by the mother's respiratory motion and still remains a challenge to obtain and track the position precisely. In this article, an algorithm which uses features from accelerated segment test (FAST) to extract the features and optical flow as the object tracking method, is proposed to deal with above problem. Further, we experimentally simulate the movement due to the mother's respiration, and the results of position errors and similarity verify the effectiveness of the proposed tracking algorithm for laser ablation endoscopy in-vitro and under water considering two influential factors. At average, the errors are about 10 pixels and the similarity over 0.92 are obtained in the experiments.

  17. Switched pattern laser projection for real-time depth extraction and visualization through endoscopes

    NASA Astrophysics Data System (ADS)

    Keller, Kurtis; Ackerman, Jeremy D.; Fuchs, Henry

    2002-09-01

    Gathering depth information through an endoscope or laparoscope during surgical or other procedures is quite difficult. There are stereo laparoscopes but generating three-dimensional models with them is very difficult. Accurate real-time generation of three-dimensional models through a laparoscope is a needed technology to enable a wide range of surgical applications. We have designed a miniature laparoscopic optical system consisting of a single laser whose pattern is modulated and uses the laparoscope as the optical display path into the body. Two cameras, one sensitive to the laser light and the other for full color imaging share this same tube as the laser projector but use the light from the opposite direction. The images gathered by the laser sensitive camera are used to generate a three dimensional map, and the color image is used to acquire the corresponding texture map. High-speed image processing hardware is used to generate 3D information using a structured light technique. The user can then re-render the acquired scene in 3D. The optical system is divided into a removable upper half consisting of the cameras, laser, digital light switches and combining optics. The lower half is the laparoscope or endocope that can be sterilized. There can be several variations in the configuration of the laparoscope optical half that tailor to different procedures.

  18. Extracorporeal piezoelectric lithotripsy for retained bile duct stones.

    PubMed

    Weber, J; Adamek, H E; Riemann, J F

    1992-05-01

    Extracorporeal piezoelectric shock wave lithotripsy (EPL) was performed in 35 patients with endoscopically non-extractable stones. With this lithotripter, stones are visualized by ultrasound and shock waves are produced by a piezoelectric acoustic generator. The stones could be localized in 32 out of 35 patients. Fragmentation was achieved in 91.4% and complete stone removal in 77.1%. These results show that piezoelectric lithotripsy is also a useful method for the treatment of complicated bile duct stones, as already demonstrated for the electrohydraulically and electromagnetically generated shock waves systems. The piezoelectric system is especially useful in elderly and frail patients because no general anesthesia is needed and only 14% of cases require analgesia or sedation.

  19. [Contact lithotripsy. Advantages and disadvantages].

    PubMed

    Iglesias Prieto, J I; Pérez-Castro Ellendt, E

    2001-11-01

    To review the different methods of contact lithotripsy by intracavitary direct contact or very close approximation of different rigid and flexible energy-transmitting devices (probes, fibers, etc.). The systems commonly used, as well as those that have fallen into disuse or have not been developed further, are briefly described. Although no contact lithotripsy system is clearly superior over another, in our experience the electrokinetic system (Walz) is highly effective and simple to use. Contact lithotripsy permits stone disintegration and removal of fragments during the same surgical procedure. It improves the rate of completeness of stone removal and permits earlier functional recovery of the obstructed renal unit.

  20. Histologic effects of different technologies for dissection in endoscopic surgery: Nd:YAG laser, high frequency and water-jet.

    PubMed

    Schurr, M O; Wehrmann, M; Kunert, W; Melzer, A; Lirici, M M; Trapp, R; Kanehira, E; Buess, G

    1994-01-01

    Precise cutting combined with reliable coagulation of the margins of the lesion is an important requirement for dissection techniques in endoscopic surgery. These requirements are met by the two most common ancillary energy sources applied for endoscopic dissection today, electrosurgery and "thermal lasers", mostly the Nd:YAG. For the comparison of the histological effects of monopolar and bipolar high frequency with the Nd:YAG laser an experimental in vitro and in vivo study has been performed. In order to evaluate the advantages of non thermal dissection for endoscopic procedures, a water jet cutting system was included in the in vitro study. In parenchymatous tissue the water jet was found to be the least traumatic technique, followed by bipolar high frequency, laser and monopolar high frequency. The water jet was not applicable for intestinal dissection since uncontrolled bloating of the rectal wall with uncontrolled disruption of the tissue layers occurred. A general disadvantage is that secure haemostasis in the line of incision is hard to achieve. In the microscopic comparison of the shape of the incision, the Nd:YAG laser produced the smoothest lesions with well-defined margins. The monopolar technique was more often associated with irregular and sometimes fissured margins. These results were confirmed in the in vivo part of the study (Transanal Endoscopic Microsurgery).

  1. Laser induced fluorescence as a diagnostic tool integrated into a scanning fiber endoscope for mouse imaging

    NASA Astrophysics Data System (ADS)

    Brown, Christopher M.; Maggio-Price, Lillian; Seibel, Eric J.

    2007-02-01

    Scanning fiber endoscope (SFE) technology has shown promise as a minimally invasive optical imaging tool. To date, it is capable of capturing full-color 500-line images, at 15 Hz frame rate in vivo, as a 1.6 mm diameter endoscope. The SFE uses a singlemode optical fiber actuated at mechanical resonance to scan a light spot over tissue while backscattered or fluorescent light at each pixel is detected in time series using several multimode optical fibers. We are extending the capability of the SFE from a RGB reflectance imaging device to a diagnostic tool by imaging laser induced fluorescence (LIF) in tissue, allowing for correlation of endogenous fluorescence to tissue state. Design of the SFE for diagnostic imaging is guided by a comparison of single point spectra acquired from an inflammatory bowel disease (IBD) model to tissue histology evaluated by a pathologist. LIF spectra were acquired by illuminating tissue with a 405 nm light source and detecting intrinsic fluorescence with a multimode optical fiber. The IBD model used in this study was mdr1a-/- mice, where IBD was modulated by infection with Helicobacter bilis. IBD lesions in the mouse model ranged from mild to marked hyperplasia and dysplasia, from the distal colon to the cecum. A principle components analysis (PCA) was conducted on single point spectra of control and IBD tissue. PCA allowed for differentiation between healthy and dysplastic tissue, indicating that emission wavelengths from 620 - 650 nm were best able to differentiate diseased tissue and inflammation from normal healthy tissue.

  2. Endoscopic laser Doppler flowmetry in the experiment and in the bleeding gastric and duodenal ulcer clinic

    NASA Astrophysics Data System (ADS)

    Kapralov, S. V.; Shapkin, Y. G.; Lychagov, V. V.; Tuchin, V. V.

    2007-05-01

    One of the most complex problems of emergency surgery is the choice of surgical tactics to deal with bleeding peptic ulcer. Endoscopic hemostasis is prescribed to patients with continuing bleedings and prerelapse syndrome. But till nowdays the objective verification of the prerelapse condition had not been worked out. What is more there are no objective criteria to judge the effectiveness of the carried endohemostasis. The aim of the study was to work out a new objective diagnostic method of pre-recurrence syndrome that can be able to make prognosis for possible gastroduodenal ulcer bleeding recurrence more precise. Laser Doppler flowmetry was the method of studies the regional perfusion. The device used in this work was made at the Optics and Biophysics Department of Saratov State University.

  3. Endoscopic endonasal transsphenoidal surgery using a skull reference array and laser surface scanning.

    PubMed

    Greenfield, J P; Howard, B M; Huang, C; Boockvar, J A

    2008-08-01

    Lesions of the skull base are increasingly being resected via the endoscopic, endonasal, transphenoidal approach. We have successfully treated 33 consecutive patients with pituitary lesions using this technique in combination with BrainLAB skull reference array and laser surface scanning for surgical navigation. This technique affords several advantages over neuronavigation based on adhesive-mounted fiducial registration. Rigid fixation in a Mayfield clamp is not required, which allows for flexibility with respect to positioning of the head during the procedure. This is particularly important as extension and flexion of the head provide greater exposure to the clivus and anterior skull base respectively. Also, this technique obviates the need for additional preoperative MRI, thereby reducing cost and delays.

  4. Endoscopic laser fragmentation and removal of a nonremovable metal esophageal stent for persistent dysphagia: a technical note.

    PubMed

    Coomber, Ross S; Patel, Pranav H; Dhir, Anubhav; Livingstone, Jeremy I

    2012-06-01

    Self-expanding metal stents are widely used in the palliation of esophageal diseases (Todd, N Engl J Med 344(22):1681-1687, 2001). The majority are inserted for end-stage malignancy and are not designed to be removed. We report the first recorded successful endoscopic removal of an "irremovable" stent by laser fragmentation after its placement became redundant. A 72-year-old man who had persistent dysphagia after esophageal stent insertion for Boerhaave's syndrome had his stent removed by Nd-YAG laser fragmentation at staged endoscopies. The stent was removed in its entirety and the patients' symptoms resolved. We describe a successful technique for the removal of a nonretrievable stent using laser fracture and endoscopic retrieval. This method of stent removal has not been previously reported.

  5. Endoscopic cystoventriculostomy and ventriculo-cysternostomy using a 2.0 micron fiber guided cw laser in children with hydrocephalus

    NASA Astrophysics Data System (ADS)

    Ludwig, Hans C.; Kruschat, Thomas; Knobloch, Torsten; Rostasy, Kevin M.; Teichmann, Heinrich O.; Buchfelder, Michael

    2005-08-01

    Preterm infants have a high incidence of post hemorrhagic or post infectious hydrocephalus often associated with ventricular or arachnoic cysts which carry a high risk of entrapment of cerebrospinal fluid (CSF). In these cases fenestration and opening of windows within the separating membranes are neurosurgical options. In occlusive hydrocephalus caused by aquaeductal stenosis 3rd ventriculostomy is the primary choice of the operative procedures. Although Nd:YAG and diode lasers have already been used in neuroendoscopic procedures, neurosurgeons avoid the use of high energy lasers in proximity to vital structures because of potential side effects. We have used a recently developed diode pumped solid state (DPSS) laser emitting light at a wavelength of 2.0 micron (Revolix TM LISA laser products, Katlenburg, Germany), which can be delivered through silica fibres towards endoscopic targets. From July 2002 until May 2005 22 endoscopic procedures in 20 consecutive patients (age 3 months to 12 years old) were performed. Most children suffered from complex post hemorrhagic and post infectious hydrocephalus, in whom ventriculoperitoneal shunt devices failed to restore a CSF equilibrium due to entrapment of CSF pathways by the cysts. We used two different endoscopes, a 6 mm Neuroendoscope (Braun Aesculap, Melsungen, Germany) and a 4 mm miniature Neuroscope (Storz, Tuttlingen, Germany). The endoscopes were connected to a standard camera and TV monitor, the laser energy was introduced through a 365 micron core diameter bare ended silica fibre (PercuFib, LISA laser products, Katlenburg, Germany) through the endoscope's working channel. The continuous wave laser was operated at power levels from 5 to 15 Watt in continuous and chopped mode. The frequency of the laser in chopped mode was varied between 5 and 20 Hz. All patients tolerated the procedure well. No immediate or long term side effects were noted. In 3 patients with cystic compression of the 4th ventricle, insertion of

  6. [The complications after CO2 laser endoscopic surgery for early glottic cancer].

    PubMed

    Bruzgielewicz, Antoni; Osuch-Wójcikiewicz, Ewa; Januszek, Grzegorz; Szwedowicz, Paweł; Domeracka-Kołodziej, Anna; Zawadzka, Renata; Niemczyk, Kazimierz

    2011-09-01

    CO(2) laser endoscopic surgery, introduction in the treatment of early glottic malignancies in the early seventies is the method has been well studied in such cases, and its utility for these lesions is well-established. Transoral resection with the CO(2) laser, open partial laryngectomy and radiotherapy are the main options for treatment of early laryngeal cancer. As all the therapies are all equally effective in controlling an early glottic cancer the choice of treatment must consider such factors as possible complications, functional outcome and patient compliance. For properly selected patients the laser therapy provides equivalent oncologic outcomes when compared to traditional surgical therapies while improving the functional aspects of postoperative speech, voice and swallowing. Its advantages over open surgery include quicker recovery, less morbidity, fewer side effects and greater cost-effectiveness too. The disadvantages of radiotherapy are: duration of treatment, loss of time for work and social activities, higher rate of other possible complications, and partial preclusion of further conservative salvage surgery. Some authors report radiotherapy offers the better quality of voice but further investigations are needed to compare the voice following endoscopic resections with that obtained after radiotherapy. The aim of the study was to analyze the character of the peri- and postoperative complications after CO(2) laser endoscopic surgery for the early glottis cancer. [corrected] This was a retrospective study of a files of 55 patients (7 female and 48 male) in age range 38-85 with early glottic carcinoma (Tis - T2) treated by cordectomy. Diagnosis was based on histopathological examination of the biopsy specimen of the lesion and ultrasonographical examination of the lymphonodules of the neck. Videolaryngostroboscopy and acustic analize of the voice was complicated. All of them underwent one of the types of cordectomy using a CO(2) laser, between 2007

  7. Clinical assessment of diode laser-assisted endoscopic intrasphenoidal vidian neurectomy in the treatment of refractory rhinitis.

    PubMed

    Lai, Wen-Sen; Cheng, Sheng-Yao; Lin, Yuan-Yung; Yang, Pei-Lin; Lin, Hung-Che; Cheng, Li-Hsiang; Yang, Jinn-Moon; Lee, Jih-Chin

    2017-10-03

    For chronic rhinitis that is refractory to medical therapy, surgical intervention such as endoscopic vidian neurectomy (VN) can be used to control the intractable symptoms. Lasers can contribute to minimizing the invasiveness of ENT surgery. The aim of this retrospective study is to compare in patients who underwent diode laser-assisted versus traditional VN in terms of operative time, surgical field, quality of life, and postoperative complications. All patients had refractory rhinitis with a poor treatment response to a 6-month trial of corticosteroid nasal sprays and underwent endoscopic VN between November 2006 and September 2015. They were non-randomly allocated into either a cold instrument group or a diode laser-assisted group. Vidian nerve was excised with a 940-nm continuous wave diode laser through a 600-μm silica optical fiber, utilizing a contact mode with the power set at 5 W. A visual analog scale (VAS) was used to grade the severity of the rhinitis symptoms for quality of life assessment before the surgery and 6 months after. Of the 118 patients enrolled in the study, 75 patients underwent cold instrument VN and 43 patients underwent diode laser-assisted VN. Patients in the laser-assisted group had a significantly lower surgical field score and a lower postoperative bleeding rate than those in the cold instrument group. Changes in the VAS were significant in preoperative and postoperative nasal symptoms in each group. The application of diode lasers for vidian nerve transection showed a better surgical field and a lower incidence of postoperative hemorrhage. Recent advancements in laser application and endoscopic technique has made VN safer and more effective. We recommend this surgical approach as a reliable and effective treatment for patients with refractory rhinitis.

  8. Endoscopic laser dacryocystorhinostomy. An unusual post-operative finding: re-opening of the nasolacrimal duct.

    PubMed

    Arullendran, P; Robson, A K; Bearn, M

    2001-12-01

    Endoscopic laser dacryocystorhinostomy (DCR) is a recognized technique for the surgical treatment of epiphora. Nasolacrimal duct obstruction is surgically bypassed by creating a passage from the lacrimal sac to the nasal cavity (rhinostomy). Some patients have undergone endonasal laser-assisted DCR, and were found to have an obstructed rhinostomy at follow-up. However, they reported a subjective improvement in their symptoms. Five such patients, at six months follow-up, were found to have a non-functioning rhinostomy with fluorescein dye emerging from under the inferior turbinate. These five patients along with four controls had post-operative macrodacryocystograms (MDCG) to delineate the anatomical passage by which tears were entering the nasal cavity. In the control group, clear passage of contrast into the middle meatus was demonstrated in three of the four subjects. In the study group, passage of dye to the inferior meatus, via the nasolacrimal duct was demonstrated in four of the five subjects. It is well recognized that a proportion of patients suffering from epiphora will have a natural resolution of their symptoms. Our results demonstrate that the resolution of epiphora in some operated patients was due to a re-opening of the nasolacrimal duct, and not because of a patent rhinostomy.

  9. Should anyone perform percutaneous endoscopic laser diskectomy and percutaneous lumbar disc decompressions?

    PubMed Central

    Epstein, Nancy E.

    2016-01-01

    Background: Increasingly, pain management specialists (P-S) (e.g., anesthesiologists, radiologists, or physiatrists), who are not spinal surgeons, are performing percutaneous endoscopic laser diskectomy (PELD), percutaneous lumbar disc decompression (PLDD), and target percutaneous laser disc decompression (T-PLDD) in patients with minimal/mild disc herniations. Here, theoretically, the laser vaporizes/shrinks a small portion of disc tissue that lowers intradiscal pressure/volume, and thereby provides “symptomatic relief” (e.g., low back pain/radiculopathy). Nevertheless, the vast majority of these patients experience spontaneous relief of their complaints over several months without any intervention. Methods: A literature review revealed that P-S specialists are performing PELD/PLDD/T-PLDD to address minimal/mild disc herniations. However, multiple well-designed studies confirmed that PELD/PLDD/T-PLDD were ineffective for managing acute/chronic pain in these patients. Results: Several randomized clinical trials documented the lack of clinical efficacy of PELD/PLDD/T-PLLD procedures over microdiskectomy. PELD/PLDD/T-PLDD correlated with only 60–70% success rates with higher reoperation rates (e.g., up to 38%) vs. 90% success rates for routine microdiskectomy (e.g., with faster recovery and only 16% reoperation rates). Nevertheless, without surgical training, P-S are performing these procedures and are, therefore, unable to adddress perioperative/postoperative PELD/PLDD/T-PLDD surgical complications. Conclusions: Pain management specialists, who are not trained spinal surgeons, should not perform PELD/PLDD/T-PLDD surgery to treat minimal/mild disc herniations. Not only do most of these discs resolve spontaneously over several months but also they are largely ineffective. Furthermore, there is no evidence to support the superiority of PELD/PLDD/T-PLDD procedures over microdiskectomy even if performed by spinal specialists. PMID:28144489

  10. Salivary Stone Pneumatic Lithotripsy in a Live Porcine Model.

    PubMed

    Walvekar, Rohan R; Hoffman, Henry T; Kolenda, Jack; Hernandez, Stephen

    2016-06-01

    The purpose of this study is to evaluate the efficacy of endoscopic fragmentation and removal of artificial calculi in a live porcine model employing intracorporeal pneumatic lithotripsy. In this experimental study, 7 submandibular ducts were accessed and artificial calculi placed. A salivary pneumatic lithotripter probe was inserted through an interventional sialendoscope to fragment the calculi. A salivary duct catheter was then used to flush stone fragments, followed by endoscopy to assess complete fragmentation and ductal trauma. Ultimately, 7 artificial stones (3-10 mm, 4F/5F) were successfully fragmented without causing significant endoluminal trauma. Number of pulses for adequate stone fragmentation averaged 20 (range, 5-31). In all cases, stone fragments were successfully flushed out with the salivary duct catheter. Postprocedure endoscopy confirmed ductal integrity in all 7 ducts. While more studies are needed, this preliminary animal model demonstrates efficacy of endoscopic pneumatic lithotripsy for the management of sialolithiasis. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  11. Blue Laser Imaging-Bright Improves Endoscopic Recognition of Superficial Esophageal Squamous Cell Carcinoma

    PubMed Central

    Tomie, Akira; Yagi, Nobuaki; Kitae, Hiroaki; Majima, Atsushi; Horii, Yusuke; Kitaichi, Tomoko; Onozawa, Yuriko; Suzuki, Kentaro; Kimura-Tsuchiya, Reiko; Okayama, Tetsuya; Kamada, Kazuhiro; Katada, Kazuhiro; Uchiyama, Kazuhiko; Ishikawa, Takeshi; Takagi, Tomohisa; Naito, Yuji; Itoh, Yoshito

    2016-01-01

    Background/Aims. The aim of this study was to evaluate the endoscopic recognition of esophageal squamous cell carcinoma (ESCC) using four different methods (Olympus white light imaging (O-WLI), Fujifilm white light imaging (F-WLI), narrow band imaging (NBI), and blue laser imaging- (BLI-) bright). Methods. We retrospectively analyzed 25 superficial ESCCs that had been examined using the four different methods. Subjective evaluation was provided by three endoscopists as a ranking score (RS) of each image based on the ease of detection of the cancerous area. For the objective evaluation we calculated the color difference scores (CDS) between the cancerous and noncancerous areas with each of the four methods. Results. There was no difference between the mean RS of O-WLI and F-WLI. The mean RS of NBI was significantly higher than that of O-WLI and that of BLI-bright was significantly higher than that of F-WLI. Moreover, the mean RS of BLI-bright was significantly higher than that of NBI. Furthermore, in the objective evaluation, the mean CDS of BLI-bright was significantly higher than that of O-WLI, F-WLI, and NBI. Conclusion. The recognition of superficial ESCC using BLI-bright was more efficacious than the other methods tested both subjectively and objectively. PMID:27738428

  12. Endoscopic cystoventriculostomy and ventriculocysternostomy using a recently developed 2.0-micron fiber-guided high-power diode-pumped solid state laser in children with hydrocephalus

    NASA Astrophysics Data System (ADS)

    Ludwig, Hans C.; Kruschat, Thomas; Knobloch, Torsten; Rostasy, Kevin; Buchfelder, Michael

    2005-04-01

    Preterm infants have a high incidence of post hemorrhagic or post infectious hydrocephalus often associated with ventricular or arachnoic cysts which carry a high risk of entrapment of cerebrospinal fluid (CSF). In these cases fenestration and opening of windows within the separating membranes are neurosurgical options. Although Nd:YAG- and diode-lasers have already been used in neuroendoscopic procedures, neurosurgeons avoid the use of high energy lasers in proximity to vital structures because of potential side effects. We have used a recently developed diode pumped solid state (DPSS) laser emitting light at a wavelength of 2.0 μm (Revolix TM LISA laser products, Katlenburg, Germany), which can be delivered through silica fibres towards endoscopic targets. From July 2002 until June 2004 fourteen endoscopic procedures in 12 consecutive patients (age 3 months to 12 years old) were performed. Most children suffered from complex post hemorrhagic and post infectious hydrocephalus, in whom ventriculoperitoneal shunt devices failed to restore a CSF equilibrium due to entrapment of CSF pathways by the cysts. We used two different endoscopes, a 6 mm Neuroendoscope (Braun Aesculap, Melsungen, Germany; a 4 mm miniature Neuroscope (Storz, Tuttlingen, Germany). The endoscopes were connected to a standard camera and TV monitor, the laser energy was introduced through a 365 μm core diameter bare ended silica fibre (PercuFib, LISA laser products, Katlenburg, Germany) through the endoscope"s working channel. The continuous wave laser was operated at power levels from 5 to 15 Watt in continuous and chopped mode. The frequency of the laser in chopped mode was varied between 5 and 20 Hz. All patients tolerated the procedure well. No immediate or long term side effects were noted. In 3 patients with cystic compression of the 4th ventricle, insertion of a shunt device could be avoided. The authors conclude that the use of the new RevolixTM laser enables safe and effective procedures

  13. Laser-induced fluorescence endoscopic imaging for detection of colonic dysplasia

    NASA Astrophysics Data System (ADS)

    Wang, Thomas D.; Wang, Yang; Van Dam, Jacques; Crawford, James M.; Preisinger, Elizabeth; Feld, Michael S.

    1995-03-01

    We are studying the use of the laser-induced fluorescence (LIF) endoscopic images of colonic mucosa for detection of pre-malignant lesions. LIF images were collected through a fiber optic colonoscope, and adenomatous polyps were used as a model of dysplasia. A total of 12 tissue samples containing 29 adenomas, obtained from colectomy specimens from 3 familial adenomatous polyposis patients, were studied. Regions of colonic mucosa were illuminated by a quartz optical fiber with near-UV light from an argon-ion laser. Autofluorescence between 400 and 700 nm was detected by means of an intensified CID camera. In the LIF images, adenomatous polyps appeared lower in intensity than normal mucosa by about a factor of 2. The LIF images were processed by dividing the raw image by a spatially averaged one to correct for differences in the distance to the tissue and in the light collection efficiency of the optics. Relative intensity thresholds were set at values varying between 55% and 90% compared to the spatial average to determine likely areas of disease. The results were compared to histology taken at 2 mm intervals along several transverse cross-sections of the specimens. At a threshold of 75%, 26 true positives, 256 true negatives, 22 false positives, and 3 false negatives were identified, resulting in a sensitivity, specificity, positive predictive value and percentage of correct determinations of 90%, 92%, 54%, and 92%, respectively. These values are comparable to results of independent diagnoses by two pathologists, demonstrating the potential of LIF to guide biopsy.

  14. Ultrasonic lithotripsy of bladder stones.

    PubMed

    Cetin, S; Ozgür, S; Yazicioğlu, A; Unsal, K; Ilker, Y

    1988-01-01

    In the second half of 1985, 15 patients with 25 bladder stones were treated with Lutzeyer's Ultrasonic Lithotriptor. Of the patients 13 underwent additional operations, mostly transurethral resection of the prostate. The average duration of lithotripsy was 30.5 minutes. Some difficulties were experienced especially when drilling hard stones and as a complication late urethral bleeding occurred in one patient.

  15. Wound healing enhancement of colonic anastomoses after endoscopic irradiation with low-power He-Ne laser: an experimental study after mechanical obstruction

    NASA Astrophysics Data System (ADS)

    Asencio-Arana, Francisco; Garcia-Fons, Vicente; Moloina-Andreu, E.

    1992-06-01

    We have tested the strength and collagen concentration of high-risk anastomoses of the rat colon after endoscopic irradiation by He-Ne laser. Repeated He-Ne laser irradiation (1.9 J/cm2) increases the bursting strength of the anastomoses by almost 100% on the fourth postoperative day. This effect is not observed by increasing the radiation dose (6.4 J/cm2). Differences in collagen (hydroxyproline) concentration did not reach statistical significance. Our study suggests that repeated endoscopic irradiation with He-Ne laser enhances the early phases of anastomotic healing in high risk colonic anastomoses.

  16. Endoscopic submucosal dissection using a thulium laser: preliminary results of a new method for treatment of gastric epithelial neoplasia.

    PubMed

    Cho, Jun-Hyung; Cho, Joo Young; Kim, Mi-Young; Jeon, Seong Ran; Lee, Tae Hee; Kim, Hyun Gun; Jin, So Young; Hong, Su Jin

    2013-09-01

    This study aimed to evaluate the feasibility of a novel laser system for endoscopic submucosal dissection (ESD) of gastric epithelial neoplasia. A total of 10 patients underwent ESD by a single expert endoscopist. A thulium 2-μm wavelength laser system was used for ESD procedures. Instead of using endoscopy knives, a 550-μm flexible silica fiber was inserted through the working channel of the endoscope. In all patients, ESD was completed using only the thulium laser, without the need for endoscopy knives. The median total procedure time was 49 minutes (range 35 - 203). In 8 /10 patients (80 %), no active bleeding was observed during ESD. The final pathologic mapping revealed low-grade dysplasia (n = 4), differentiated adenocarcinoma (n = 5), and signet ring cell carcinoma (n = 1). Curative resection was achieved in 9 /10 patients (90 %). There were no significant complications, such as delayed bleeding or perforation. The thulium laser system was feasible in ESD of gastric epithelial neoplasia. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Endoscopic treatment of sessile rectal adenomas: comparison of Nd:YAG laser therapy and injection-assisted piecemeal polypectomy.

    PubMed

    De Palma, G D; Caiazzo, C; Di Matteo, E; Capalbo, G; Catanzano, C

    1995-06-01

    This prospective study was carried out in order to compare endoscopic laser therapy with injection-assisted piecemeal polypectomy for treatment of sessile rectal adenomas. We randomized 94 patients with rectal sessile adenomas to either of the two treatments. The adenomas were classified according to size as extensive or intermediate. Of the patients with extensive adenomas, a complete ablation was achieved in 63.6% with laser versus 33.3% with piecemeal snaring (p < .01). For the intermediate adenomas, the rates of permanent ablation were 81.2% with laser versus 86.6% with piecemeal snaring polypectomy (difference not statistically significant). The complication rates were acceptable in both the laser and piecemeal snaring groups. (One case of perforation and one case of stenosis were observed in the laser group, both probably related to prior electroresection.) Our study suggests that the specific indication for laser therapy should be extensive lesions; with intermediate adenomas, laser therapy and injection-assisted piecemeal polypectomy are equally efficacious for achieving complete ablation. However, the duration of initial treatment differs: 6.3 weeks for laser therapy versus 2.4 weeks for piecemeal polypectomy; moreover, about 70% of the intermediate adenomas were eradicated with a single session of piecemeal polypectomy.

  18. Optimal power settings for Holmium:YAG lithotripsy.

    PubMed

    Sea, Jason; Jonat, Lee M; Chew, Ben H; Qiu, Jinze; Wang, Bingqing; Hoopman, John; Milner, Thomas; Teichman, Joel M H

    2012-03-01

    We determined the optimal Ho:YAG lithotripsy power settings to achieve maximal fragmentation, minimal fragment size and minimal retropulsion. Stone phantoms were irradiated in water with a Ho:YAG laser using a 365 μm optical fiber. Six distinct power settings were tested, including 0.2 to 2.0 J and 10 to 40 Hz. For all cohorts 500 J total radiant energy were delivered. A seventh cohort (0.2 J 40 Hz) was tested post hoc to a total energy of 1,250 J. Two experimental conditions were tested, including with and without phantom stabilization. Total fragmentation, fragment size and retropulsion were characterized. In mechanism experiments using human calculi we measured crater volume by optical coherence tomography and pressure transients by needle hydrophone across similar power settings. Without stabilization increased pulse energy settings produced increased total fragmentation and increased retropulsion (each p <0.0001). Fragment size was smallest for the 0.2 J cohorts (p <0.02). With stabilization increased pulse energy settings produced increased total fragmentation and increased retropulsion but also increased fragment size (each p <0.0001). Craters remained symmetrical and volume increased as pulse energy increased. Pressure transients remained modest at less than 30 bars even at 2.0 J pulse energy. Holmium:YAG lithotripsy varies as pulse energy settings vary. At low pulse energy (0.2 J) less fragmentation and retropulsion occur and small fragments are produced. At high pulse energy (2.0 J) more fragmentation and retropulsion occur with larger fragments. Anti-retropulsion devices produce more efficient lithotripsy, particularly at high pulse energy. Optimal lithotripsy laser dosimetry depends on the desired outcome. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  19. Voice quality after endoscopic laser surgery and radiotherapy for early glottic cancer: objective measurements emphasizing the Voice Handicap Index

    PubMed Central

    Caminero Cueva, Maria Jesús; Señaris González, Blanca; Llorente Pendás, José Luis; Gorriz Gil, Carmen; López Llames, Aurora; Alonso Pantiga, Ramón; Suárez Nieto, Carlos

    2007-01-01

    We analyzed the functional outcome and self-evaluation of the voice of patients with T1 glottic carcinoma treated with endoscopic laser surgery and radiotherapy. We performed an objective voice evaluation, as well as a physical, emotional and functional well being assessment of 19 patients treated with laser surgery and 18 patients treated with radiotherapy. Voice quality is affected both by surgery and radiotherapy. Voice parameters only show differences in the maximum phonation time between both treatments. Results in the Voice Handicap Index show that radiotherapy has less effect on patient voice quality perception. There is a reduced impact on the patient’s perception of voice quality after radiotherapy, despite there being no significant differences in vocal quality between radiotherapy and laser cordectomy. PMID:17999074

  20. Endoscopic ultrasound-guided needle-based confocal laser endomicroscopy in solid pancreatic masses.

    PubMed

    Giovannini, Marc; Caillol, Fabrice; Monges, Geneviève; Poizat, Flora; Lemaistre, Anne-Isabelle; Pujol, Bertrand; Lucidarme, Damien; Palazzo, Laurent; Napoléon, Bertrand

    2016-10-01

    The differential diagnosis of solid pancreatic masses by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is currently suboptimal in centers that are not equipped with rapid on-site evaluation. Needle-based confocal laser endomicroscopy (nCLE) enables real-time in vivo microscopic imaging during endoscopy. This study aimed to describe nCLE interpretation criteria for the characterization of pancreatic masses, with histopathological correlation, and to perform the first validation of these criteria. A total of 40 patients were evaluated by EUS-FNA combined with nCLE for the diagnosis of pancreatic masses. Final diagnosis was based on EUS-FNA histology and follow-up at 1 year. Five unblinded examiners defined nCLE criteria for adenocarcinoma, chronic pancreatitis, and neuroendocrine tumor (NET) using a set of video sequences from 14 patients with confirmed pathology (Step 1). These criteria were retrospectively validated by four independent, blinded examiners using sequences from 32 patients (Step 2). nCLE criteria were described for adenocarcinoma (dark cell aggregates, irregular vessels with leakages of fluorescein), chronic pancreatitis (residual regular glandular pancreatic structures), and NET (black cell aggregates surrounded by vessels and fibrotic areas). These criteria correlated with the histological features of the corresponding lesions. In the validation review, a conclusive nCLE result was obtained in 75 % of cases (96 % correct). Statistical evaluation provided promising results, with high specificity, and negative and positive predictive values for all types of pancreatic masses. Considering the low negative predictive value of EUS-FNA, nCLE could help to rule out malignancy after a previous inconclusive EUS-FNA. Larger studies are required to confirm these findings and to establish the role of nCLE in the diagnosis of pancreatic masses. ClinicalTrials.gov (NCT01563133). © Georg Thieme Verlag KG Stuttgart · New York.

  1. Transurethral endoscopic treatment of patients with upper tract urothelial carcinomas using neodymium-YAG and/or holmium-YAG laser ablation.

    PubMed

    Tada, Yasuhiro; Yokomizo, Akira; Koga, Hirohumi; Seki, Naruhito; Kuroiwa, Kentaro; Tatsugami, Katsunori; Yamaguchi, Akito; Naito, Seiji

    2010-08-01

    To report our experience of treating patients with original and recurrent upper tract urothelial carcinomas (UC) using endoscopic lasers, with holmium-YAG and/or neodymium-YAG laser ablation, and for whom tumour stage and grade were obtained by endoscopic biopsy. From March 2003 to March 2007, 15 patients with upper tract UC were treated with endoscopic laser ablation as the primary management. Patients were followed up by intravenous urography, computed tomography, urine cytology and/or ureteroscopic surveillance at 3- to 12-month intervals. The median (range) follow-up was 25.5 (13-51) months. Of the 15 patients, five had an upper tract recurrence during the follow-up. Three of these were treated with total nephroureterectomy and two had a progression in tumour stage or grade. Three patients had residual tumours; they were treated with repeated endoscopic laser treatments and had no recurrence over a median (range) of 24 (13-26) months. The renal preservation rate was 12/15 and the local recurrence rate was six/15 after the initial endoscopy. The median operative duration and tumour size were 60 min and 10 mm, respectively. Patients with low-grade and -stage disease and normal contralateral kidneys also benefit from this approach, if there is an adequate endoscopic biopsy. As the operative duration tended to be associated with the maximum tumour size, this treatment is potentially available for a maximum tumour size of <4 cm; if the tumour is <4 cm surgery will require <120 min.

  2. Feasibility of endoscopic laser speckle imaging modality in the evaluation of auditory disorder: study in bone-tissue phantom

    NASA Astrophysics Data System (ADS)

    Yu, Sungkon; Jang, Seulki; Lee, Sangyeob; Park, Jihoon; Ha, Myungjin; Radfar, Edalat; Jung, Byungjo

    2016-03-01

    This study investigates the feasibility of an endoscopic laser speckle imaging modality (ELSIM) in the measurement of perfusion of flowing fluid in optical bone tissue phantom(OBTP). Many studies suggested that the change of cochlear blood flow was correlated with auditory disorder. Cochlear microcirculation occurs under the 200μm thickness bone which is the part of the internal structure of the temporal bone. Concern has been raised regarding of getting correct optical signal from hard tissue. In order to determine the possibility of the measurement of cochlear blood flow under bone tissue using the ELSIM, optical tissue phantom (OTP) mimicking optical properties of temporal bone was applied.

  3. A multicenter, randomized, controlled trial of transureteral and shock wave lithotripsy--which is the best minimally invasive modality to treat distal ureteral calculi in children?

    PubMed

    Basiri, Abbas; Zare, Samad; Tabibi, Ali; Sharifiaghdas, Farzaneh; Aminsharifi, Alireza; Mousavi-Bahar, Seyed Habibollah; Ahmadnia, Hassan

    2010-09-01

    Since there is insufficient evidence to determine the best treatment modality in children with distal ureteral calculi, we designed a multicenter, randomized, controlled trial to evaluate the efficacy and complications of transureteral and shock wave lithotripsy in these patients. A total of 100 children with distal ureteral calculi were included in the study. Of the patients 50 were randomized consecutively to undergo shock wave lithotripsy using a Compact Delta II lithotriptor (Dornier MedTech, Kennesaw, Georgia), and 50 were randomized to undergo transureteral lithotripsy with holmium laser and pneumatic lithotriptor between February 2007 and October 2009. Stone-free, complication and efficiency quotient rates were assessed in each group. Mean +/- SD patient age was 6.5 +/- 3.7 years (range 1 to 13). Mean stone surface was 35 mm(2) in the transureteral group and 37 mm(2) in the shock wave lithotripsy group. Stone-free rates at 2 weeks after transureteral lithotripsy and single session shock wave lithotripsy differed significantly, at 78% and 56%, respectively (p = 0.004). With 2 sessions of shock wave lithotripsy the stone-free rate increased to 72%. Efficiency quotient was significantly higher for transureteral vs shock wave lithotripsy (81% vs 62%, p = 0.001). Minor complications were comparable and negligible between the groups. Two patients (4%) who underwent transureteral lithotripsy sustained a ureteral perforation. In the short term it seems that transureteral and shock wave lithotripsy are acceptable modalities for the treatment of distal ureteral calculi in children. However, transureteral lithotripsy has a higher efficacy rate when performed meticulously by experienced hands using appropriate instruments. 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  4. Use of endoscopic distal attachment cap to enhance image stabilization in probe-based confocal laser endomicroscopy in colorectal lesions*

    PubMed Central

    Ussui, Vivian; Xu, Can; Crook, Julia E.; Diehl, Nancy N.; Hardee, Joy; Staggs, Estela G.; Shahid, Muhammad W.; Wallace, Michael B.

    2015-01-01

    Background and study aims: Colorectal cancer can be prevented through the use of colonoscopy with polypectomy. Most colon polyps are benign or low grade adenomas. However, currently all lesions need histopathologic analysis, which increases diagnostic costs and delays the final diagnosis. Confocal laser endomicroscopy (CLE) is a new technology that enables real-time endomicroscopy. However, there are challenges to maintaining a stable image with currently available systems. We conducted a small study to obtain a preliminary assessment of whether the use of an endoscopic distal attachment cap may enhance image quality of CLE in comparison with images obtained with free-hand acquisition. Patients and methods: Forty outpatients underwent colonoscopy for evaluation of colon polyps in a single academic medical center. Patients were assigned randomly to 1 of 2 study arms on the basis of whether an endoscopic distal attachment cap was used (n = 21, Cap Used) or not used (n = 19, No Cap) in the procedure. The quality of confocal images and probe stabilization was summarized. Results: A total of 81 polyps were identified. The proportion of polyps with images of high quality was 74 % (28/38) in the Cap Used group and 79 % (30/38) in the No Cap arm. Image stability was also similar with and without a cap. Diagnostic accuracy was estimated to be slightly higher in the Cap Used group for probe-based confocal laser endomicroscopy (pCLE; 78 % vs 70 %). This was also true for white-light and narrow-band imaging. Conclusions: This preliminary study did not yield any evidence to support that the use of an endoscopic distal attachment cap improves the quality of images obtained during CLE. PMID:26528511

  5. Use of endoscopic distal attachment cap to enhance image stabilization in probe-based confocal laser endomicroscopy in colorectal lesions.

    PubMed

    Ussui, Vivian; Xu, Can; Crook, Julia E; Diehl, Nancy N; Hardee, Joy; Staggs, Estela G; Shahid, Muhammad W; Wallace, Michael B

    2015-10-01

    Colorectal cancer can be prevented through the use of colonoscopy with polypectomy. Most colon polyps are benign or low grade adenomas. However, currently all lesions need histopathologic analysis, which increases diagnostic costs and delays the final diagnosis. Confocal laser endomicroscopy (CLE) is a new technology that enables real-time endomicroscopy. However, there are challenges to maintaining a stable image with currently available systems. We conducted a small study to obtain a preliminary assessment of whether the use of an endoscopic distal attachment cap may enhance image quality of CLE in comparison with images obtained with free-hand acquisition. Forty outpatients underwent colonoscopy for evaluation of colon polyps in a single academic medical center. Patients were assigned randomly to 1 of 2 study arms on the basis of whether an endoscopic distal attachment cap was used (n = 21, Cap Used) or not used (n = 19, No Cap) in the procedure. The quality of confocal images and probe stabilization was summarized. A total of 81 polyps were identified. The proportion of polyps with images of high quality was 74 % (28/38) in the Cap Used group and 79 % (30/38) in the No Cap arm. Image stability was also similar with and without a cap. Diagnostic accuracy was estimated to be slightly higher in the Cap Used group for probe-based confocal laser endomicroscopy (pCLE; 78 % vs 70 %). This was also true for white-light and narrow-band imaging. This preliminary study did not yield any evidence to support that the use of an endoscopic distal attachment cap improves the quality of images obtained during CLE.

  6. Introduction of an ultrathin and flexible laser scanning endoscope for color imaging and integrated PDD and future PDT

    NASA Astrophysics Data System (ADS)

    Seibel, Eric J.; Kenerson, Heidi L.; Lee, Cameron M.; Melville, C. David; Johnston, Richard S.; Yeung, Raymond S.

    2009-06-01

    The scanning fiber endoscope (SFE), an ultrathin laser scanning endoscope capable of producing 500-line color images at 30-Hz frame rate, has been developed at the University of Washington. The SFE probe is a 1-mm diameter by 9-mm long rigid scanner at the tip of a highly flexible and robust tether (minimum bend radius < 8- mm), comprised of helically wound optical fibers and electrical wires within a protective sheath. The unique physical characteristics of this system have allowed the camera to navigate narrow passages where other technologies have suffered from reduced image quality and fragility, such as imaging the peripheral airways and bile duct. The scanning engine of the SFE allows for laser-based imaging and potential applications of pixel-accurate therapy in remote regions of the body. In this study, the standard SFE operation has been tailored to create widefield fluorescence images for photodynamic detection. A kidney with renal cell carcinoma was excised from an Eker rat after post-mortem in situ perfusion with 0.4 mM hypericin. The 442-nm blue and 532-nm green laser illumination sources were used for both standard reflectance imaging and fluorescence excitation, while the red 635- nm illumination was disabled. Red detection signal gain was increased to amplify the red fluorescence signal from the photomultiplier tube and within the computer image display. Results show green and blue reflectance images overlaid with red fluorescence signal in tumor regions of the kidney. These imaging capabilities portend future adoption of laser-based SFE imaging for real-time PDD.

  7. Novel device for tissue cooling during endoscopic laryngeal laser surgery: thermal damage study in an ex vivo calf model.

    PubMed

    Koo, Hae Jin; Burns, James A; Kobler, James B; Heaton, James T; Zeitels, Steven M

    2012-07-01

    Minimizing collateral thermal damage during endoscopic laryngeal laser surgery remains a priority, and tissue cooling is one way to achieve this goal. Cooling systems utilizing compressed air have been shown to reduce the extent of thermal trauma on the vocal folds, but these units are not ideal for endoscopic applications because cooling is inefficient at the low airflows needed. We examined whether a novel vortex cooling device that generates cooled air at low flow rates would provide a cooling benefit beyond that which could be obtained by using room-temperature air for cooling tissue or by using no cooling during simulated laryngeal laser surgery. A continuous-wave thulium laser was used to incise glottic tissue in 12 calf vocal folds. Cooling was achieved with a prototype vortex cooler (9 degrees C air output; flow rate, 3 L/min), and tissue temperature measurements were compared to those with room-air cooling and no cooling. Thermal damage was analyzed histologically by measuring the depth of lactate dehydrogenase inactivation surrounding the mucosal incision. The cooling conditions were tested during time-constant cuts (8 seconds) and depth-constant cuts (into the thyroarytenoid muscle). During time-constant cuts, comparison between vortex cooling and room-air cooling revealed that vortex cooling resulted in a thermal damage zone that was 14% smaller (519 versus 603 microm; p < 0.05). During depth-constant cuts, vortex cooling created a thermal damage zone that was 32% smaller than that created with no cooling (p <0.01) and 9% smaller than that created with room-air cooling (p < 0.01). Vortex cooling reduces thermal damage more effectively than room-air cooling or no cooling during both time-constant and depth-constant thulium laser cuts.

  8. Extracorporeal shockwave lithotripsy of gallstones. Possibilities and limitations.

    PubMed Central

    Vergunst, H; Terpstra, O T; Brakel, K; Laméris, J S; van Blankenstein, M; Schröder, F H

    1989-01-01

    Recently extracorporeal shockwave lithotripsy (ESWL) has been introduced as a nonoperative treatment for gallstone disease. Except for lung damage, no significant adverse effects of ESWL of gallbladder stones have been observed in animals. In clinical use ESWL of gallbladder stones is now confined to 15% to 30% of symptomatic patients. To achieve complete stone clearance, ESWL of gallbladder stones must be supplemented by an adjuvant therapy. ESWL of bile duct stones is highly effective and can be considered in patients in whom primary endoscopic or surgical stone removal fails. Second generation lithotriptors allow anesthesia-free (outpatient) treatments, but the clinical experience with most of these ESWL devices is still limited. The likelihood of gallbladder stone recurrence is a major disadvantage of ESWL treatment, which raises the issue of cost-effectiveness. ESWL for cholelithiasis is a promising treatment modality with good short-term and unknown long-term results. PMID:2684058

  9. Endoscopic Cyclophotocoagulation

    PubMed Central

    Seibold, Leonard K.; SooHoo, Jeffrey R.; Kahook, Malik Y.

    2015-01-01

    In recent years, many new procedures and implants have been introduced as safer alternatives for the surgical treatment of glaucoma. The majority of these advances are implant-based with a goal of increased aqueous drainage to achieve lower intraocular pressure (IOP). In contrast, endoscopic cyclophotocoagulation (ECP) lowers IOP through aqueous suppression. Although ciliary body ablation is a well-established method of aqueous suppression, the novel endoscopic approach presents a significant evolution of this treatment with marked improvement in safety. The endoscope couples a light source, video imaging, and diode laser to achieve direct visualization of the ciliary processes during controlled laser application. The result is an efficient and safe procedure that can achieve a meaningful reduction in IOP and eliminate or reduce glaucoma medication use. From its initial use in refractory glaucoma, the indications for ECP have expanded broadly to include many forms of glaucoma across the spectrum of disease severity. The minimally-invasive nature of ECP allows for easy pairing with phacoemulsification in patients with coexisting cataract. In addition, the procedure avoids implant or device-related complications associated with newer surgical treatments. In this review, we illustrate the differences between ECP and traditional cyclophotocoagulation, then describe the instrumentation, patient selection, and technique for ECP. Finally, we summarize the available clinical evidence regarding the efficacy and safety of this procedure. PMID:25624669

  10. Endoscopic treatment of pancreatic calculi.

    PubMed

    Kim, Yong Hoon; Jang, Sung Ill; Rhee, Kwangwon; Lee, Dong Ki

    2014-05-01

    Chronic pancreatitis is a progressive inflammatory disease that destroys pancreatic parenchyma and alters ductal stricture, leading to ductal destruction and abdominal pain. Pancreatic duct stones (PDSs) are a common complication of chronic pancreatitis that requires treatment to relieve abdominal pain and improve pancreas function. Endoscopic therapy, extracorporeal shock wave lithotripsy (ESWL), and surgery are treatment modalities of PDSs, although lingering controversies have hindered a consensus recommendation. Many comparative studies have reported that surgery is the superior treatment because of reduced duration and frequency of hospitalization, cost, pain relief, and reintervention, while endoscopic therapy is effective and less invasive but cannot be used in all patients. Surgery is the treatment of choice when endoscopic therapy has failed, malignancy is suspected, or duodenal stricture is present. However, in patients with the appropriate indications or at high-risk for surgery, endoscopic therapy in combination with ESWL can be considered a first-line treatment. We expect that the development of advanced endoscopic techniques and equipment will expand the role of endoscopic treatment in PDS removal.

  11. [Quantitative renal DMSA scintigraphy after extracorporeal lithotripsy].

    PubMed

    Coulange, C; Siles, S; Rossi, D; Vaillant, J L; Soler, B; Kaphan, G; Rampal, M

    1990-01-01

    This study reports the results of renal DMSA isotope scan before and after EDAP extracorporeal lithotripsy in 106 patients. An isotope scan was performed before lithotripsy and on the fourth day after lithotripsy and again on the 90th day when alterations were observed on the first post-lithotripsy scan. The assessment of any sequelae was based on the scale of colours of the spectrum, which revealed three types of modifications. The analysis of the results is divided into three periods according to the development in our lithotripsy technique: high firing rates had a success rate of only 40%, with renal scars on isotope scans in 2/3 of cases; low frequency firing rates had a 55% success rate and induced minor changes which were virtually always reversible; in contrast, low frequency firing rates during the 3rd period had a 60% success rate with scars on isotope scans in 1/3 of cases. These isotope scan modifications also depended on the site of the stone. In conclusion, lithotripsy definitely induces renal modifications. The renal parenchyma cannot remain indifferent to lithotripsy beyond a certain threshold. A homogeneous multicentre study with a common protocol is necessary to compare the various lithotriptors and to define cautious and coherent indications for each lithotriptor in the treatment of renal stones.

  12. Endoscopic holmium laser excision of intravesical tension-free vaginal tape and polypropylene suture after anti-incontinence procedures.

    PubMed

    Giri, Subhasis K; Drumm, John; Flood, Hugh D

    2005-10-01

    We report on our technique of endoscopic excision of intravesical tension-free vaginal tape procedure and polypropylene sutures using the holmium laser following various anti-incontinence procedures. Three patients who previously underwent the tension-free vaginal tape, Burch colposuspension and Stamey vesicopexy, respectively, presented with a range of symptoms including hematuria, recurrent urinary tract infection, frequency, urgency and urinary incontinence. Patients were evaluated with history and examination, and all 3 were found to have nonabsorbable intravesical material. There was obvious encrustation over the eroded polypropylene material within the bladder. A 365 microm tip firing holmium laser fiber was inserted through the working channel of the flexible cystoscope. The tape and sutures were successfully excised using a holmium laser output of 1.0 J per pulse at a rate of 10 Hz. Mean operative time was 15 minutes. Holmium laser excision of intravesical polypropylene tape or suture is a minimally invasive solution to the problem of intravesical perforation or erosion following anti-incontinence procedures.

  13. Endoscopic disconnection of hypothalamic hamartomas: safety and feasibility of robot-assisted, thulium laser-based procedures.

    PubMed

    Calisto, Amedeo; Dorfmüller, Georg; Fohlen, Martine; Bulteau, Christine; Conti, Alfredo; Delalande, Olivier

    2014-12-01

    Hypothalamic hamartomas (HH) may induce drug-resistant epilepsy (DRE), thereby requiring surgical treatment. Conventionally, treatment is aimed at removing the lesion, but a disconnection procedure has been shown to be safer and at least as effective. The thulium laser (Revolix) has been recently introduced in urological endoscopy because of its ability to deliver a smooth cut with good control of the extent of tissue damage. The authors sought to analyze the safety and efficacy of the thulium 2-μm laser applied through navigated, robot-assisted endoscopy in disconnection surgery for HHs. Twenty patients with HH who were drug resistant were treated during a 12-month period. Conventional disconnection by monopolar coagulation (endoscopic electrode) was performed in 13 patients, and thulium laser disconnection was performed in the remaining 7 patients. The endoscope was inserted into the ventricle contralateral to the attachment of the HH on the third ventricular wall. Results in terms of safety, efficacy, and ease of use of the instrument were analyzed. All 20 patients achieved a satisfactory postoperative Engel score (Classes I-III). At 12 months, the Engel class was I or II in 8 of 13 patients (61.5%) who underwent monopolar coagulation and in 6 of 7 patients (85.7%) who underwent laser disconnection (p = 0.04). Seven of 13 patients (53.8%) who underwent monopolar coagulator disconnection and 2 of 7 patients (28.6%) who underwent laser disconnection had immediate postoperative complications. At the 3-month follow-up, only 2 patients (15.4%) treated by coagulation still experienced mild surgery-related recent memory deficits. No complications persisted at the 12-month follow-up. The disconnection procedure is a safe and effective treatment strategy to treat drug-resistant epilepsy in patients with HHs. With the limitations of initial experience and a short-term follow-up, it appears that the thulium 2-μm laser has the technical features to replace the standard

  14. Cervical Deuk Laser Disc Repair®: A novel, full-endoscopic surgical technique for the treatment of symptomatic cervical disc disease

    PubMed Central

    Deukmedjian, Ara J.; Cianciabella, Augusto; Cutright, Jason; Deukmedjian, Arias

    2012-01-01

    Background: Cervical Deuk Laser Disc Repair® is a novel full-endoscopic, anterior cervical, trans-discal, motion preserving, laser assisted, nonfusion, outpatient surgical procedure to safely treat symptomatic cervical disc diseases including herniation, spondylosis, stenosis, and annular tears. Here we describe a new endoscopic approach to cervical disc disease that allows direct visualization of the posterior longitudinal ligament, posterior vertebral endplates, annulus, neuroforamina, and herniated disc fragments. All patients treated with Deuk Laser Disc Repair were also candidates for anterior cervical discectomy and fusion (ACDF). Methods: A total of 142 consecutive adult patients with symptomatic cervical disc disease underwent Deuk Laser Disc Repair during a 4-year period. This novel procedure incorporates a full-endoscopic selective partial decompressive discectomy, foraminoplasty, and posterior annular debridement. Postoperative complications and average volume of herniated disc fragments removed are reported. Results: All patients were successfully treated with cervical Deuk Laser Disc Repair. There were no postoperative complications. Average volume of herniated disc material removed was 0.09 ml. Conclusions: Potential benefits of Deuk Laser Disc Repair for symptomatic cervical disc disease include lower cost, smaller incision, nonfusion, preservation of segmental motion, outpatient, faster recovery, less postoperative analgesic use, fewer complications, no hardware failure, no pseudoarthrosis, no postoperative dysphagia, and no increased risk of adjacent segment disease as seen with fusion. PMID:23230523

  15. Sialendoscopy with holmium:YAG laser treatment for multiple large sialolithiases of the Wharton duct: a case report and literature review.

    PubMed

    Sun, Yu-Ting; Lee, Kuo-Sheng; Hung, Shih-Han; Su, Chin-Hui

    2014-12-01

    Sialolithiasis is defined as calcified stone(s) in the salivary duct or glands. Submandibular gland sialolithiasis is the most common (80 to 90%), followed by parotid gland sialolithiasis (5 to 15%). The typical clinical presentation is salivary gland swelling after eating. As the swelling persists, symptoms owing to local inflammation, such as pain and trismus, emerge. In severe cases, cellulitis and even abscess formation occur and subsequently lead to salivary gland atrophy or fistula formation if the sialolithiasis remains untreated. The most common treatment is complete excision of the affected gland together with the stone(s). In some cases, intraoral sialolithotomy is performed when the stone is solitary and easily palpable through the oral cavity. Sialendoscopy is increasingly performed because of its minimal invasiveness. The major limitation of endoscopic laser lithotripsy of the salivary glands is the size of the stone. Often, for a stone larger than 4 mm, multiple fragmentations of the stone into small pieces is necessary before the pieces can be removed by wire basket or grasping forceps. Recently, the holmium:YAG laser has been reported as quite effective in removing larger salivary gland stones. However, sialoendoscopic laser lithotripsy is a very time-consuming procedure and in most cases, when there are multiple large stones in a single gland, entire gland excision is recommended. This report describes a male patient diagnosed with multiple large stones in his left submandibular gland who was successfully treated under sialendoscopy with holmium:YAG laser lithotripsy.

  16. Experimental application of pulsed laser-induced water jet for endoscopic submucosal dissection: mechanical investigation and preliminary experiment in swine.

    PubMed

    Sato, Chiaki; Nakano, Toru; Nakagawa, Atsuhiro; Yamada, Masato; Yamamoto, Hiroaki; Kamei, Takashi; Miyata, Go; Sato, Akira; Fujishima, Fumiyoshi; Nakai, Masaaki; Niinomi, Mitsuo; Takayama, Kazuyoshi; Tominaga, Teiji; Satomi, Susumu

    2013-05-01

    A current drawback of endoscopic submucosal dissection (ESD) for early-stage gastrointestinal tumors is the lack of instruments that can safely assist with this procedure. We have developed a pulsed jet device that can be incorporated into a gastrointestinal endoscope. Here, we investigated the mechanical profile of the pulsed jet device and demonstrated the usefulness of this instrument in esophageal ESD in swine. The device comprises a 5-Fr catheter, a 14-mm long stainless steel tube for generating the pulsed water jet, a nozzle and an optical quartz fiber. The pulsed water jet was generated at pulse rates of 3 Hz by irradiating the physiological saline (4°C) within the stainless steel tube with an holmium-doped yttrium-aluminum-garnet (Ho:YAG) laser at 1.1 J/pulse. Mechanical characteristics were evaluated using a force meter. The device was used only for the part of submucosal dissection in the swine ESD model. Tissues removed using the pulsed jet device and a conventional electrocautery device, and the esophagus, were histologically examined to assess thermal damage. The peak impact force was observed at a stand-off distance of 40 mm (1.1 J/pulse). ESD using the pulsed jet device was successful, as the tissue specimens showed precise dissection of the submucosal layer. The extent of thermal injury was significantly lower in the dissected bed using the pulsed jet device. The results showed that the present endoscopic pulsed jet system is a useful alternative for a safe ESD with minimum tissue injury. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

  17. Comparison of the clinical efficacy and safety of retroperitoneal laparoscopic ureterolithotomy and ureteroscopic holmium laser lithotripsy in the treatment of obstructive upper ureteral calculi with concurrent urinary tract infections.

    PubMed

    Jiang, Jun-Tao; Li, Wei-Guo; Zhu, Yi-Ping; Sun, Wen-Lan; Zhao, Wei; Ruan, Yuan; Zhong, Chen; Wood, Kristofer; Wei, Hai-Bin; Xia, Shu-Jie; Sun, Xiao-Wen

    2016-07-01

    The aim of this study is to compare the clinical efficacy and safety of retroperitoneal laparoscopic ureterolithotomy (RPLU) and ureteroscopic holmium laser lithotripsy (UHLL) as two minimally invasive procedures in managing obstructive upper ureteral calculi with concurrent urinary tract infections (UTI). The retrospective study included 189 patients who underwent unilateral obstructive upper ureteral stones with concurrent UTI from January 2007 to November 2014 at our institution. Patients received RPLU (81 cases) or UHLL (108 cases). All patients received preoperative anti-infection treatment (indwelling ureteral stent and/or preoperative antibiotics). Collected data, including sex, age, stone size, success rate, operation duration, post-operation hospitalization time, and post-operation complications, were compared. All patients were followed up for more than 6 months after surgeries, and no ureterostenosis occurred. The study included 189 patients, 41 (21.7 %) females and 148 (78.3 %) males with a medium age of 52 years (range 22-81 years). All surgeries were successfully performed without conversion to open surgery. Stone size in the RPLU group was larger than that of the UHLL group (16.1 ± 1.4 vs. 10.4 ± 1.6 mm, P = 0.012). Operative duration (P = 0.009) and hospitalization time (P < 0.001) in the UHLL group were significantly shorter than those in the RPLU group, whereas stone clearance rate was significantly higher in the RPLU group (100 vs. 88.9 %, P = 0.002). Of note, postoperative fever was more common in patients treated with UHLL (15 cases) versus RPLU (4 cases) (13.9 vs. 4.9 %, P = 0.043). Moreover, in the UHLL group, three patients without a preoperative indwelling ureteral stent were complicated with sepsis, which was not seen in RPLU group. In our study, the safety and stone clearance rate of RPLU are better than those of UHLL in the treatment of unilateral upper ureteric calculi with concurrent UTI

  18. Preventing stone retropulsion during intracorporeal lithotripsy.

    PubMed

    Elashry, Osama M; Tawfik, Ahmad M

    2012-12-01

    Several studies of ureteroscopic treatment for ureteral stones have reported that most stone clearance failures can be attributed to stone fragment retropulsion. Stone retropulsion can result in increased operative time and cost-resulting from the need to change from the semi-rigid ureteroscope to a flexible instrument to chase migrated calculi-and additional procedures to treat residual migrated fragments are often required. The degree of migration depends mainly on the energy source used for lithotripsy; pneumatic and electrohydraulic lithotripters are associated with a greater degree of retropulsion than lasers. Different stone-trapping strategies and devices have been developed to minimize stone migration. Novel devices include the Lithovac(®) suction device, the Passport(™) balloon, the Stone Cone(™), the PercSys Accordion(®), the NTrap(®), and stone baskets such as the LithoCatch(™), the Parachute(™), and the Escape(®). Some authors have also reported on the use of lubricating jelly and BackStop(®) gel (a reverse thermosensitive polymeric plug); these devices are instilled proximal to the stone prior to the application of kinetic energy in order to prevent retrograde stone migration.

  19. Our experience with transcanalicular laser-assisted endoscopic dacryocystorhinostomy (TCLADCR) in patients of chronic dacryocystitis with deviated nasal septum.

    PubMed

    Goel, Ruchi; Nagpal, Smriti; Kumar, Sushil; Kamal, Saurabh; Dangda, Sonal; Bodh, Sonam Angmo

    2015-12-01

    The purpose of this study is to study the operative difficulties and success rate of transcanalicular laser-assisted endoscopic dacryocystorhinostomy in patients of chronic dacryocystitis with deviated nasal septum (DNS). A prospective interventional clinical study of 36 consecutive patients suffering from chronic dacryocystitis with nasolacrimal duct obstruction with DNS undergoing primary TCLADCR from March to June 2011 was carried out. Diode laser was used to create a 16-mm(2) ostium which was enlarged to 64 mm(2) using Blakesley's forceps. Success was defined as anatomical patency and absence of symptoms at 12 months of follow-up. Out of the 36 patients, 25 were females with ages 20-72 years, and 19 were left sided. There were 12 high, 12 mid and 12 basal DNS towards the side of surgery, mild to moderate in severity. Intraoperatively there was difficulty in visualising the aiming beam in the nose, tedious manipulation of endoscope and excessive bleeding in 3 patients. Increased bleeding and failures were significantly higher in high DNS (Fisher exact test-2 tailed: 0.0045). The procedure was successful in 94.4 % cases with average ostium size of 21.94 mm(2) at 12 months and no statistically significant difference in success rates between mild and moderate DNS (Fisher exact test-2 tailed: 1.000). Also there was no difference in the complication rate between mild and moderate DNS (Fisher exact test-2 tailed: 0.0841). TCLADCR is an effective procedure in patients with mild to moderate mid and basal DNS and obviates the need for multiple procedures and a cutaneous scar.

  20. Variable-focus side-firing endoscopic device

    NASA Astrophysics Data System (ADS)

    Lemberg, Vladimir G.; Black, Michael

    1996-05-01

    Conventional side-firing fiber technology exhibits performance limitations and utilizes expensive single-use only devices which often require multiple fibers for laser prostatectomy. Another limitation of existing side-firing fiber technology is its inability to focus the beam to create incisions for urologic applications such as laser TURP (transurethral resectional prostatectomy), tumor necrosis, lithotripsy, genital warts, and photodynamic therapy. Newly introduced variable-focus side-firing endoscopic device utilizes either one or two lenses and a mirror, onto a single cylinder of molded glass. The laser beam exits the optical fiber, passes through the lens, strikes the cylindrical mirror, and traverses the cylindrical surface. Depending on the design, the laser beam is reflected at the angles ranging from 30 degrees to 120 degrees out of the cylindrical lens. A second lens can be formed onto the side of the cylindrical surface at the beam's exit point. Another advantage of the innovative side-firing device is its capability to provide versatile matching to multiple laser wavelengths from 360 nm to 2.5 microns, and achieve power densities great enough to perform vaporization, incision and coagulation of tissue. Precise focusing of the laser beam results in reduced tissue necrosis of surrounding the treatment area as well as in decreased laser radiation back-scattering. Surgeons can very the focus by adjusting the distance from the tip to the target area. The variable focus side-firing device provides a focused beam at the range of 1.0 to 1.5 mm, for incision. Outside this range, it produces a defocused beam for coagulation.

  1. A review of Thulium fiber laser ablation of kidney stones

    NASA Astrophysics Data System (ADS)

    Fried, Nathaniel M.; Blackmon, Richard L.; Irby, Pierce B.

    2011-02-01

    The clinical solid-state Holmium:YAG laser lithotripter (λ=2120 nm) is capable of operating at high pulse energies, but its efficient operation is limited to low pulse rates during lithotripsy. The diode-pumped experimental Thulium Fiber Laser (λ=1908 nm) is limited to low pulse energies, but can operate at high pulse rates. This review compares stone ablation threshold, ablation rate, and retropulsion effects for Ho:YAG and TFL. Laser lithotripsy complications also include optical fiber bending failure resulting in endoscope damage and low irrigation rates leading to poor visibility. Both problems are related to fiber diameter and limited by Ho:YAG laser multimode spatial beam profile. This study exploits TFL spatial beam profile for higher power transmission through smaller fibers. A short taper is also studied for expanding TFL beam at the distal tip of a small-core fiber. Stone mass loss, stone crater depths, fiber transmission losses, fiber burn-back, irrigation rates, and deflection through a flexible ureteroscope were measured for tapered fiber and compared with conventional fibers. The stone ablation threshold for TFL was four times lower than for Ho:YAG. Stone retropulsion with Ho:YAG increased linearly with pulse energy. Retropulsion with TFL was minimal at pulse rates < 150 Hz, then rapidly increased at higher pulse rates. TFL beam profile provides higher laser power through smaller fibers than Ho:YAG laser, potentially reducing fiber failure and endoscope damage and allowing greater irrigation rates for improved visibility and safety. Use of a short tapered distal fiber tip also allows expansion of the laser beam, resulting in decreased fiber tip damage compared to conventional fibers, without compromising fiber bending, stone ablation efficiency, or irrigation rates.

  2. Extracorporeal shock wave lithotripsy in childhood

    SciTech Connect

    Kroovand, R.L.; Harrison, L.H.; McCullough, D.L.

    1987-10-01

    Extracorporeal shock wave lithotripsy is the treatment of choice for the majority of upper urinary calculi in adults. Technical limitations, including patient size and concerns over post-treatment stone fragment passage, have made the application of extracorporeal shock wave lithotripsy in children less clearly defined. We report the successful application of the Dornier lithotriptor in the management of 18 children (22 kidneys) with upper urinary calculi.

  3. Does a retropulsion prevention device equalize the surgical success of Ho:YAG laser and pneumatic lithotripters for upper ureteral stones? A prospective randomized study.

    PubMed

    Bagbanci, Sahin; Dadali, Mumtaz; Dadalı, Yeliz; Emir, Levent; Gorgulu, Ozkan; Karabulut, Ayhan

    2016-10-19

    To establish if a retropulsion prevention device for ureteral stones equalizes surgical success and push-back rates of Ho:YAG laser and pneumatic lithotripters for upper ureteral stones. Patients with upper ureteral stones (n = 267) were treated endoscopically at the Department of Urology between April 2014 and December 2015. Patients were randomly assigned to pneumatic and Ho:YAG laser lithotripters as group-1 and group-2, respectively. Lithotripsy was performed with Stone Cone(TM) in both groups. The surgical success rate on the first postoperative day was 81.5 % (n = 106) and 90.6 % (n = 116) for group-1 and group-2, respectively, and the difference between the groups was statistically significant (p < 0.05). The relation between stone size and surgical success was statistically significant for both groups (p < 0.01). Surgical success for the stones closer than 2 cm to the UPJ was 23.1 % for the pneumatic group versus 64 % for the laser group (p < 0.01). Lithotripsy time was significantly longer in group-2 (16.48 ± 4.74 min) than group-1 (12.24 ± 3.95 min) (p < 0.01). Ho:YAG laser lithotripsy is more successful than pneumatic lithotripsy for upper ureteral stones and a retropulsion prevention device does not equalize the surgical success of Ho:YAG laser and pneumatic lithotripters for upper ureteral stones on the first postoperative day and one month after surgery. Although the success rate of the first month after surgery is higher in group-2, the difference is not statistically significant.

  4. CO(2) laser versus cold steel margin analysis following endoscopic excision of glottic cancer.

    PubMed

    Makki, Fawaz M; Rigby, Matthew H; Bullock, Martin; Brown, Timothy; Hart, Robert D; Trites, Jonathan; Hinni, Michael L; Taylor, S Mark

    2014-02-06

    To compare the suitability of CO2 laser with steel instruments for margin excision in transoral laser microsurgery. Prospective randomized blinded study. Patients with glottic cancer undergoing laser resection were randomized to margin excision by either steel instruments or CO2 laser. Margins were analyzed for size, interpretability and degree of artifact by a pathologist who was blinded to technique. 45 patients were enrolled in the study with 226 total margins taken. 39 margins taken by laser had marked artifact and 0 were uninterpretable. 20 margins taken by steel instruments had marked artifact, and 2 were uninterpretable. Controlling for margin size, the laser technique was associated with increasing degrees of margin artifact (p = 0.210), but there was no difference in crude rates of uninterpretability (p = 0.24). Laser margin excision is associated with a greater degree of artifact than steel instrument excision, but was not associated with higher rate of uninterpretability.

  5. Analgesia for shock wave lithotripsy.

    PubMed

    Parkin, John; Keeley FX, Francis X; Timoney, Anthony G

    2002-04-01

    We evaluated the effectiveness of and patient preference for analgesia used during shock wave lithotripsy by comparing diclofenac alone with a combination of diclofenac and patient controlled analgesia, that is alfentanil. A total of 64 patients were treated using a Lithotriptor S (Dornier Medical Systems, Marietta, Georgia) and randomized to receive diclofenac alone or combined with an alfentanil patient controlled analgesia pump. If treated twice, they crossed over to the alternative form of analgesia. A record was maintained of the site and size of the stone, maximum power achieved, number of shocks, amount of alfentanil used and need for additional analgesia. After treatment patients scored on a visual analog scale the maximum level of pain and satisfaction with analgesia. There was no difference in the mean size of the stone treated (8.6 and 7.5 mm.), energy level (71% and 71% or approximately 17 kV.) or number of shocks (3,000 and 2,900, respectively) in the groups. Only 2 patients in the diclofenac group required additional analgesia and there were no significant side effects from either treatment. The mean pain scores were not significantly different in the diclofenac and patient controlled analgesia groups (3.54 and 2.93, respectively, (p = 0.34), although those on patient controlled analgesia were more satisfied (7.72 versus 9.14, p = 0.04). Of the 38 patients who presented twice 58% preferred diclofenac alone. This study suggests that there is no significant difference in the level of pain experienced with diclofenac alone or when combined with an alfentanil patient controlled analgesia pump during shock wave lithotripsy. However, patients are more satisfied with treatment when a patient controlled analgesia pump is available.

  6. [Rigid ureteroscopy and the pulsed laser. Apropos of 325 treated calculi].

    PubMed

    Gautier, J R; Leandri, P; Rossignol, G; Quintens, H; Caissel, J

    1990-01-01

    A pulsed dye laser (Candela) was used in our lithiasis treatment center during the period 02/88-09/89 to remove 325 calculi in 278 patients, requiring 285 endoscopic instrumentations. The pulsed laser allowed to obtain fragmentation of 318 calculi, 238 of which were reduced to thin sand and 80 to coarser fragments. The latter were either cleared using a Dormia probe or further disintegrated by electrohydrolytic shock wave treatment or extracorporeal shock wave lithotripsy (ESWL). No complication imputable to laser stone fragmentation was noted. Failure of stone clearance was chiefly due to the nature and shape of the stone (black, smooth monohydrated calcium oxalate calculi). The thinness of the laser fiber has made it possible to use small caliber ureteroscopes, thereby increasing the reliability of ureteroscopy. Coupled with ESWL (EDAP LT01), this technique has caused the rate of open surgical removal of ureter confined calculi to fall from 11% to 1%.

  7. Functional results of endoscopic laser surgery in advanced head and neck tumors

    NASA Astrophysics Data System (ADS)

    Sadick, Haneen; Baker-Schreyer, Antonio; Bergler, Wolfgang; Maurer, Joachim; Hoermann, Karl

    1998-01-01

    Functional results following lasersurgery of minor laryngeal carcinomas were very encouraging. The indication for lasersurgical intervention was then extended to larger carcinomas of the larynx and hypopharynx. The purpose of this study was to assess vocal function and swallowing ability after endoscopic lasersurgery and to compare the results with conventional surgical procedures. From January 1994 to December 1996, 72 patients with advanced squamous cell carcinoma of the larynx and hypopharynx were examined prospectively. The patients underwent endoscopic lasersurgery instead of laryngopharyngectomy. The voice quality was evaluated pre- and postoperatively by subjective assessment, registration of voice parameters and sonegraphic classification. The swallowing ability was judged according to individual scores. The necessity of tracheostomy and nasogastric tube were registered and the duration of hospitalization was documented. The results showed that laryngeal phonation and swallowing ability were significantly better 12 months after lasersurgery compared to the preoperative findings whereas the recurrence rate was similar or even better after conventional pharyngolaryngectomy. Lasersurgery as an alternative surgical procedure to laryngectomy enables patients to retain a sufficient voice function and swallowing ability.

  8. Endoscopic endonasal cranial base surgery simulation using an artificial cranial base model created by selective laser sintering.

    PubMed

    Oyama, Kenichi; Ditzel Filho, Leo F S; Muto, Jun; de Souza, Daniel G; Gun, Ramazan; Otto, Bradley A; Carrau, Ricardo L; Prevedello, Daniel M

    2015-01-01

    Mastery of the expanded endoscopic endonasal approach (EEA) requires anatomical knowledge and surgical skills; the learning curve for this technique is steep. To a great degree, these skills can be gained by cadaveric dissections; however, ethical, religious, and legal considerations may interfere with this paradigm in different regions of the world. We assessed an artificial cranial base model for the surgical simulation of EEA and compared its usefulness with that of cadaveric specimens. The model is made of both polyamide nylon and glass beads using a selective laser sintering (SLS) technique to reflect CT-DICOM data of the patient's head. It features several artificial cranial base structures such as the dura mater, venous sinuses, cavernous sinuses, internal carotid arteries, and cranial nerves. Under endoscopic view, the model was dissected through the nostrils using a high-speed drill and other endonasal surgical instruments. Anatomical structures around and inside the sphenoid sinus were accurately reconstructed in the model, and several important surgical landmarks, including the medial and lateral optico-carotid recesses and vidian canals, were observed. The bone was removed with a high-speed drill until it was eggshell thin and the dura mater was preserved, a technique very similar to that applied in patients during endonasal cranial base approaches. The model allowed simulation of almost all sagittal and coronal plane EEA modules. SLS modeling is a useful tool for acquiring the anatomical knowledge and surgical expertise for performing EEA while avoiding the ethical, religious, and infection-related problems inherent with use of cadaveric specimens.

  9. Transoral Endoscopic Head and Neck Surgery and Its Role Within the Multidisciplinary Treatment Paradigm of Oropharynx Cancer: Robotics, Lasers, and Clinical Trials.

    PubMed

    Holsinger, F Christopher; Ferris, Robert L

    2015-10-10

    Transoral endoscopic head and neck surgery is a new approach for the treatment of oropharyngeal tumors. Using either a robotic system and/or laser, surgeons gain access through the mouth via minimally invasive technique and thus have improved visualization of the tumors of the oropharynx, without disfiguring incisions. This transoral route of access minimizes long-term speech and swallowing dysfunction. Surgeons view this approach as a considerable technologic advance, analogous to the evolution in radiation therapy from conventional two- and three-dimensional conformal techniques to intensity-modulated techniques. Although the use of radiation with or without chemotherapy to treat oropharyngeal cancer (OPC) is supported by evidence from prospective clinical trials, there are no prospective data supporting the use of this new surgical approach for OPC. Here, we review the fundamentals of transoral endoscopic head and neck surgery, with robotics and laser technology, and discuss ongoing clinical trials for patients with OPC. © 2015 by American Society of Clinical Oncology.

  10. Transoral Endoscopic Head and Neck Surgery and Its Role Within the Multidisciplinary Treatment Paradigm of Oropharynx Cancer: Robotics, Lasers, and Clinical Trials

    PubMed Central

    Holsinger, F. Christopher; Ferris, Robert L.

    2015-01-01

    Transoral endoscopic head and neck surgery is a new approach for the treatment of oropharyngeal tumors. Using either a robotic system and/or laser, surgeons gain access through the mouth via minimally invasive technique and thus have improved visualization of the tumors of the oropharynx, without disfiguring incisions. This transoral route of access minimizes long-term speech and swallowing dysfunction. Surgeons view this approach as a considerable technologic advance, analogous to the evolution in radiation therapy from conventional two- and three-dimensional conformal techniques to intensity-modulated techniques. Although the use of radiation with or without chemotherapy to treat oropharyngeal cancer (OPC) is supported by evidence from prospective clinical trials, there are no prospective data supporting the use of this new surgical approach for OPC. Here, we review the fundamentals of transoral endoscopic head and neck surgery, with robotics and laser technology, and discuss ongoing clinical trials for patients with OPC. PMID:26351337

  11. Complications and Failures of Office-Based Endoscopic Angiolytic Laser Surgery Treatment.

    PubMed

    Del Signore, Anthony G; Shah, Rupali N; Gupta, Nikita; Altman, Kenneth W; Woo, Peak

    2016-11-01

    Although office-based laser surgery applications for benign and premalignant lesions of the larynx are appealing, there are scant data on their complications and failures. We review office-based angiolytic laser surgery in patients with benign laryngeal pathology for rates of complication and failure. Retrospective chart review. Two hundred fifty-five patients who underwent in-office angiolytic laser surgery treatment over 4 years were reviewed. The criteria for complications and failures were based on postprocedure stroboscopy and clinical findings. The majority of patients had unilateral disease, which included polyps (46%), leukoplakia (14%), papilloma (13%), scar (12%), and varix (11%). There were 382 laser treatments, of which 56% were by pulsed potassium titanyl phosphate laser. Average energy delivery was lesion specific, with papilloma receiving the most (mean 351 J) and varices receiving the least (mean 53 J) energy. Most in-office treatments were tolerated well. Four percent of patients had complications including stiffness, atrophy, and transient but prolonged hyperemia. Twenty-seven percent of patients required multiple laser treatments. Multiple treatments were more likely in papilloma and leukoplakia. While in-office laser therapy for benign vocal fold lesions is appealing, repeated treatment due to incomplete resolution may be needed. Risks of transient and long-term complications are low but real. Patient selection and standardized laser energy parameters may help in decreasing complications and need for repeat procedures. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  12. Cleaning of endodontic root canal by ultrasonics and Nd:YAG laser beam with fiber optic delivery: scanning electron microscopy, endoscopic and microradiographic analysis

    NASA Astrophysics Data System (ADS)

    Berna, Norberto; Melis, Marco; Benvenuti, Alessandro; Tosto, Sebastiano; Pierdominici, Fabrizio

    1997-05-01

    12 teeth have been extracted and treated 'in vitro' by ultrasonics and Nd:YAG pulsed laser with fiber optic delivery to compare the cleaning efficiency of the root canal. The optic fiber was equipped with a water-air coaxial cooling system. The ultrasonic device was equipped with a 3 percent NaCl solution douche system. The samples have been prepared according to the technical specifications of the suppliers of laser and ultrasonics and observed by an endodontic endoscope. Cross sections of the samples have been utilized for microradiographic investigations and scanning electron microscopy observations. Local melting has been observed after laser irradiation.Also, vitrification preferentially occurred in the apical zones. The occurrence of vitrification was found strongly dependent on the translation velocity of the laser beam inside the root canal. The laser beam has shown a cleaning efficiency greater than that obtained by ultrasonic procedure.

  13. Confocal Laser Endomicroscopy in the Management of Endoscopically Treated Upper Urinary Tract Transitional Cell Carcinoma: Preliminary Data.

    PubMed

    Villa, Luca; Cloutier, Jonathan; Cotè, Jean-Francois; Salonia, Andrea; Montorsi, Francesco; Traxer, Olivier

    2016-02-01

    To describe our initial experience with confocal laser endomicroscopy (CLE) for the evaluation and treatment of patients with upper urinary tract transitional cell carcinoma (UUT-TCC). Preliminary data were analyzed from 11 patients with suspicion of UUT-TCC scheduled for flexible ureteroscopy (f-URS) and consensual holmium-YAG laser tumor ablation. CLE was performed before endoscopic biopsy and laser photoablation of the suspected lesion using a 3F-diameter flexible probe UroFlex™ B (Cellvizio® system; Mauna Kea Technologies, Paris, France), which allows to obtain microscopic resolution imaging (3.5 μm), with a field of view of 325 μm and a depth of tissue imaging of 40 to 70 μm. Video sequences were analyzed offline and thereafter compared with histopathologic findings. CLE technique was feasible and showed good quality imaging in all patients. Overall, the Cellvizio system provided reliable images of healthy urothelium when the probe was pointed toward normal tissue, showing umbrella cells on the surface and vessels in the lamina propria. Moreover, CLE displayed the characteristic features of high-density cellular aggregates and fibrovascular stalks in four patients with pathologically confirmed low-grade UUT-TCC. In the patient with pathologically confirmed high-grade UUT-TCC, more distorted microarchitecture and tortuous vessels were clearly recognized with CLE. These preliminary data showed the feasibility of CLE technique when applied to the diagnosis of UUT-TCC. Further clinical studies are required to confirm CLE accuracy in distinguishing healthy urothelial tissue from malignant lesions, thus helping clinicians in targeting ureteroscopic biopsy and improving the conservative management of UUT-TCC patients.

  14. Nd:YAG laser treatment for benign lesions of vocal cord through fiber endoscope

    NASA Astrophysics Data System (ADS)

    Pin, Wei-Zheng

    1993-03-01

    This paper describes 120 cases with benign lesions of the vocal cord, such as the polyp and the nodule, treated by laser irradiation and application of Nd:YAG laser and optical fiber carried out through fiber laryngoscope under surface anaesthesia. One-hundred-eleven of the cases were cured, 9 improved, and 0 failed. This method is superior to other methods and has the following features: accuracy, rapidity, non-bleeding, painlessness, easy operation, rare complication, and good effect.

  15. Oncological and complication assessment of CO2 laser-assisted endoscopic surgery for T1-T2 glottic tumours: clinical experience.

    PubMed

    Galli, A; Giordano, L; Sarandria, D; Di Santo, D; Bussi, M

    2016-06-01

    Several therapeutic options are used for treatment of early stage glottic carcinoma (Tis/T1/T2): open partial laryngectomy (OPL), radiotherapy and CO2 laser-assisted endoscopic surgery. Laser surgery has gradually gained approval in the management of laryngeal cancer. We present our experience in endoscopic laser surgery for early stage glottic carcinomas. This was a retrospective analysis of 72 patients with T1-T2 glottic cancer treated with laser cordectomy between 2006 and 2012. All patients had at least a 36-month follow-up period. Percentages for disease-specific survival, disease-free survival (DFS) and laryngeal preservation rates were 98.6%, 84.7% and 97.2% respectively. Considering neoplastic features that could predict long-term oncological outcome, tumoural involvement of anterior commissure and pathological staging (pT) significantly correlate with local recurrence (p = 0.021 and p = 0.035) and with a lowered DFS (p = 0.017 and p = 0.023). Other variables such as clinical staging, type of cordectomy, involvement of other structures and surgical margin status showed no significant impact on oncological endpoints. CO2 laser surgery is a reliable technique for T1-T2 glottic cancer considering oncological outcomes. The recurrence rate seems to be affected by involvement of anterior commissure and pT stage.

  16. Perspective on Lithotripsy Adverse Effects

    NASA Astrophysics Data System (ADS)

    Knoll, Thomas; Wendt-Nordahl, Gunnar

    2008-09-01

    Shock wave lithotripsy (SWL) is an effective and without any doubt the least invasive procedure to treat upper urinary tract calculi. Acute complications are rarely reported and do not require specific treatment in most cases. However, one should be aware that energy levels sufficient for stone breakage are capable of damaging tissue as well, and significant hematoma—not only in the kidney but as well in surrounding organs—has been observed. Furthermore, only little is known about the long-term effects of SWL. Some authors have reported an increased incidence of hypertension and possibly also diabetes mellitus. Such chronic diseases—if indeed related to prior SWL—may be a late result of acute SWL-related trauma but the discussion on the underlying pathogenesis is controversial. Many factors have to be considered, such as the natural history of recurrent stone formers, technical principles of SWL, and differences in treatment protocols. Promising studies are currently underway to optimize stone breakage while limiting potential collateral damage. With this progress, SWL remains a safe treatment option for most urinary calculi.

  17. Cavitation in shock wave lithotripsy

    NASA Astrophysics Data System (ADS)

    Bailey, Michael R.; Crum, Lawrence A.; Sapozhnikov, Oleg A.; Evan, Andrew P.; McAteer, James A.; Colonius, Tim; Cleveland, Robin O.

    2003-10-01

    A case is presented for the important role of cavitation in stone comminution and tissue injury in shock wave lithotripsy (SWL). Confocal hydrophones and a coincidence algorithm were used to detect cavitation in kidney parenchyma. Elevated hydrostatic pressure dissolved cavitation nuclei and suppressed cell injury and stone comminution in vitro. A low-insertion-loss, thin, mylar film nearly eliminated stone erosion and crack formation only when in direct contact with the stone. This result indicates not only that cavitation is important in both cracking and erosion but also that bubbles act at the surface. Time inversion of the shock wave by use of a pressure-release reflector reduced the calculated pressure at bubble collapse and the measured depth of bubble-induced pits in aluminum. Correspondingly tissue injury in vivo was nearly eliminated. Cavitation was localized and intensified by the use of synchronously triggered, facing lithotripters. This dual pulse lithotripter enhanced comminution at its focus and reduced lysis in surrounding blood samples. The enhancement of comminution was lost when stones were placed in glycerol, which retarded bubble implosion. Thus, cavitation is important in comminution and injury and can be controlled to optimize efficacy and safety. [Work supported by NIH DK43381, DK55674, and FIRCA.

  18. Extracorporeal shock wave lithotripsy today

    PubMed Central

    Tailly, Geert G

    2013-01-01

    Even 32 years after its first introduction shockwave lithotripsy (SWL) remains a matter of discussion and controversy. Since the first SWL in 1980, millions of treatments have been performed worldwide. To this day SWL remains the least invasive of all stone treatments and is considered the treatment modality of first choice for the majority of urinary stones. Despite the massive scale on which SWL is performed in a wide range of indications, complication rate has always remained very low and usually limited to minor side effects and complications. The introduction of affordable multifunctional lithotripters has made SWL available to more and more departments of urology worldwide. Still many centers are disappointed with the treatment results and concerned about the adverse tissue effects. In this SWL proves to be the victim of its uninvasiveness and its apparent ease of practice. Urologists need proper skill and experience; however, to adequately administer shockwaves in order to improve outcome. This aspect is too often minimized and neglected. Apart from this the power of shockwaves often is underestimated by operators of shockwave machines. Basic knowledge of the physics of shockwaves could further reduce the already minimal adverse tissue effects. Good training and coaching in the administration of shockwaves would no doubt lead to a renaissance of SWL with better treatment results and minimal adverse tissue effects. PMID:24082441

  19. Extracorporeal shock wave lithotripsy today.

    PubMed

    Tailly, Geert G

    2013-07-01

    Even 32 years after its first introduction shockwave lithotripsy (SWL) remains a matter of discussion and controversy. Since the first SWL in 1980, millions of treatments have been performed worldwide. To this day SWL remains the least invasive of all stone treatments and is considered the treatment modality of first choice for the majority of urinary stones. Despite the massive scale on which SWL is performed in a wide range of indications, complication rate has always remained very low and usually limited to minor side effects and complications. The introduction of affordable multifunctional lithotripters has made SWL available to more and more departments of urology worldwide. Still many centers are disappointed with the treatment results and concerned about the adverse tissue effects. In this SWL proves to be the victim of its uninvasiveness and its apparent ease of practice. Urologists need proper skill and experience; however, to adequately administer shockwaves in order to improve outcome. This aspect is too often minimized and neglected. Apart from this the power of shockwaves often is underestimated by operators of shockwave machines. Basic knowledge of the physics of shockwaves could further reduce the already minimal adverse tissue effects. Good training and coaching in the administration of shockwaves would no doubt lead to a renaissance of SWL with better treatment results and minimal adverse tissue effects.

  20. Endoscopic palliation of esophageal and cardial cancer: Nd:YAG laser and prosthesis

    NASA Astrophysics Data System (ADS)

    Norberto, Lorenzo; Ranzato, Riccardo; Marino, Saverio; Angriman, Imerio; Vella, Vincenzo; Donadi, Michele; D'Amico, D. F.

    1997-12-01

    From November 1, 1992 to January 31, 1997, 227 patients with inoperable esophageal and cardial carcinomas were treated with Nd:YAG laser therapy and prosthesis intubation. The retrograde technique was used in most cases. The tumor involved in 75 pts the Cardia, in 65 the middle thoracic esophagus, in 47 pts the lower thoracic esophagus, in 23 in the upper thoracic esophagus and in 17 in the cervical esophagus. The indications for palliative Nd:YAG laser and prosthesis intubation were a locally advanced or metastatic tumor in 146 pts (64.4%) and poor surgical risk in 81 pts (35.6%). The quality of palliation was evaluated according to the ability to swallow. The mean survival rate of the patients during the follow up was 22 weeks for the laser therapy and 16 weeks for the prosthesis intubation.

  1. Diode laser-assisted endoscopic dacryocystorhinostomy: a comparison of three different combinations of adjunctive procedures.

    PubMed

    Dogan, Remzi; Meric, Aysenur; Ozsütcü, Mustafa; Yenigun, Alper

    2013-08-01

    Chronic dacryocystitis is a frequently encountered condition which can be corrected by dacryocystorhinostomy. Today, the diode laser is increasingly put to use in such corrective operations. This study aims to answer the questions of which adjunctive procedures and which combinations of such procedures are necessary and effective in securing more successful outcomes in diode laser dacryocystorhinostomy. This prospective randomized study included eighty patients (13 male, 67 female) who underwent dacryocystorhinostomy in our hospital during the 2 year period of January 2009-January 2011. The patients were selected consecutively and were randomly allocated to three groups. Group 1 (30): diode laser + mitomycin C + silicone intubation; Group 2 (27): diode laser + silicone intubation; Group 3 (23): diode laser + mitomycin C. All patients were evaluated postoperatively on day 1, week 1, and on the 1st, 3rd, 6th, 12th, 18th, and 24th months. The postoperative evaluation consisted of preoperative and postoperative ostium measurements, recording postoperative complications, and calculating and comparing success rates and operative times. The mean ages of the patients were 63.4 for Group 1, 60.7 for Group 2, and 61.8 for Group 3. No statistically significant difference was found among the groups regarding pre- and postoperative ostium measurements. The success rates were 84.3, 80, and 76.9 % for Groups 1, 2, and 3, respectively. Complications noted in Group 1 were restenosis (3), premature silicone tube loss (1), development of granulation tissue (3), synechia (2), infection (2), and hemorrhage (3). Those for Group 2 were restenosis (5), premature tube loss (2), granulation (8), synechia (6), infection (3), and hemorrhage (4). Group 3 had 6 cases with stenosis, 5 with granulation, 3 with infection, 6 with synechia, and 5 with hemorrhage. The operative times of the groups were 25.5, 15.3, and 18.1 min, respectively, for Group 1, 2, and 3. All three groups had statistically

  2. Flexible ureteroscopic lithotripsy for the treatment of upper urinary tract calculi in infants

    PubMed Central

    Li, Jun; Han, Tiandong; Tian, Ye; Wang, Wenying; Du, Yuan

    2016-01-01

    We evaluated the clinical value of flexible ureteroscopic lithotripsy for the treatment of upper urinary tract calculi in infants. Fifty-five infants with upper urinary tract calculi were included in this study: 41 males and 14 females. Retrograde intrarenal surgery was performed by an 8 Fr/30 cm flexible ureterorenoscope (POLY®) combined with a holmium laser. CT scanning or radiography of the kidneys, ureters, and bladder region was performed one month after the operation to confirm the clearance of calculi. All the 55 infants with calculi in 74 sides underwent 66 flexible ureteroscopic lithotripsy procedures. The median operation time was 30 min. The median amount of flushing fluid was 500 mL. The stone-free rate after a single session treatment was 94.6%, within which 10 infants underwent simultaneous bilateral flexible ureteroscopy lithotripsy. Catheters were retained in 45 infants for 24–48 h after the operation. Continuous high fever due to reflux was present in two cases. Flushing fluid extravasation was found in one infant. Some patients with minor complications, such as mild hematuria, irritation symptoms, and low fever, recovered without treatment. The duration of hospitalization time after the operation was approximately 1–5 days. Flexible ureteroscopic lithotripsy is a safe, highly efficient, minimally invasive, and reproducible operation for removal of upper urinary tract calculi in infants. This technique is a convenient method for postoperative management of patients that enhances their rapid recovery. It is a promising option for therapy of infants ineffectively treated by extracorporeal shockwave lithotripsy. PMID:27633576

  3. Flexible ureteroscopic lithotripsy for the treatment of upper urinary tract calculi in infants.

    PubMed

    Li, Jun; Xiao, Jing; Han, Tiandong; Tian, Ye; Wang, Wenying; Du, Yuan

    2017-01-01

    We evaluated the clinical value of flexible ureteroscopic lithotripsy for the treatment of upper urinary tract calculi in infants. Fifty-five infants with upper urinary tract calculi were included in this study: 41 males and 14 females. Retrograde intrarenal surgery was performed by an 8 Fr/30 cm flexible ureterorenoscope (POLY®) combined with a holmium laser. CT scanning or radiography of the kidneys, ureters, and bladder region was performed one month after the operation to confirm the clearance of calculi. All the 55 infants with calculi in 74 sides underwent 66 flexible ureteroscopic lithotripsy procedures. The median operation time was 30 min. The median amount of flushing fluid was 500 mL. The stone-free rate after a single session treatment was 94.6%, within which 10 infants underwent simultaneous bilateral flexible ureteroscopy lithotripsy. Catheters were retained in 45 infants for 24-48 h after the operation. Continuous high fever due to reflux was present in two cases. Flushing fluid extravasation was found in one infant. Some patients with minor complications, such as mild hematuria, irritation symptoms, and low fever, recovered without treatment. The duration of hospitalization time after the operation was approximately 1-5 days. Flexible ureteroscopic lithotripsy is a safe, highly efficient, minimally invasive, and reproducible operation for removal of upper urinary tract calculi in infants. This technique is a convenient method for postoperative management of patients that enhances their rapid recovery. It is a promising option for therapy of infants ineffectively treated by extracorporeal shockwave lithotripsy.

  4. Miniaturized optical fiber endoscope without inertial scan for simultaneous imaging and laser microsurgery

    NASA Astrophysics Data System (ADS)

    Adam, Jost; Metz, Philipp; Gerken, Martina; Jalali, Bahram

    2013-09-01

    The current autostereoscopic projection system is accomplished by array projectors. It is easy to realize optically but has a drawback with size. Another type is to place the shutter on the screen. It saves the volume but reduces the efficiency depending on how many views are produced. The shutter in the lens aperture has the same efficiency problem, too. To overcome these problems, a full HD autostereoscopic projector based on the lens aperture switching type is proposed. It has RGB laser sources and can produce 16-views or even higher stereoscopic images. This system removes the shutter in the lens aperture by the opti-mechanism itself. The specific light on the lens aperture coming from the point on the DMD is reflected to different angles. The proper angle of light is generated in the object side by the relay and folding system. The UHP lamps or the LED rays are difficult to constrain in a relative small cone angle. For this reason, the laser is applied to the design. The very small etendue of the laser is good for this architecture. The rays are combined by dichroic filter from RGB laser sources then forming and expanding to the mirror. The mirror is synchronized with DMD by the DSP control system. The images of different views are generated by DMD and specific position of the mirror. By the double lenticular screen, the lens aperture is imaged to the observer's viewing zone and the 3D scene is created.

  5. Retrospective measures on applying endoscopic YAG laser to treat alimentary canal diseases from 1983 to 1995

    NASA Astrophysics Data System (ADS)

    Wang, Rui-Zhong; Wu, Ning-Xiao; Gao, Su-ping; Rong, Zeng-Qin

    1996-05-01

    It was in 1983 when we started to apply YAG laser to do experiments on animal and fresh internal organs off the body to confirm its effectiveness. Then we started to use it in clinical practice. Up to October 1995, in the twelve years, we treated 1075 cases, 2574 person times. Seven-hundred-seventy-nine cases of various esophagostenosis. Four-hundred-fifty-six of them were malignant stenosis, 295 anastomostenosis, 15 stenosis after radiotherapeutics, 7 corrosive anastomostenosis, 6 inflammatory anastomostenosis, plus we cured 5 cardia losses of relax, and 241 polyps in the alimentary canal. Among the 2154 polyps cured, 6 were that of esophagus, 6 that of cardia, 25 that of stomach, 10 that of duodenum, 194 that of large intestine. In addition, we treated 15 alimentary canal bleeding and 35 malignant colon and tectum cancers. Our experience in laser operating on the coelom has become richer and richer. The methods we used are being widened. The range of our laser application is being enlarged. We have gained our own experience in preventing complications and keeping the endoscopy from being damaged. The cure rate of the non-malignant had raised up to 98.7%. Cure rate of the malignant had raised up to 91%. The alimentary canal polyps can be cured perfectly. It is hard to tell whether YAG laser or high frequency electroresection has the advantage over the other. Besides, this paper is going to put forward several questions to discuss.

  6. The value of extracorporeal shock-wave lithotripsy in the management of bile duct stones.

    PubMed

    Lee, S H; Fache, J S; Burhenne, H J

    1990-10-01

    We evaluated the role of biliary extracorporeal shock-wave lithotripsy in treating 70 symptomatic patients with bile duct stones in whom endoscopic or percutaneous radiologic attempts at basket extraction had failed. Forty-four patients had common bile and/or common hepatic duct stones, 21 patients had cystic duct stones, and five patients had intrahepatic duct stones. A total of 43 patients (61%) had complete elimination of stone fragments during the initial treatment period. If patients in whom stones were successfully fragmented yet not totally eliminated on initial hospital treatment but who were asymptomatic at follow-up times of 8-22 months are included, the overall successful treatment rate was 83%. Stones were cleared in 26 of 44 common bile/hepatic duct stone patients, spontaneously in seven patients and after endoscopic or percutaneous radiologic intervention in 19 patients. Fifteen (71%) of 21 patients had cystic duct stones successfully cleared. The fragments in two of five patients with intrahepatic duct stones also were cleared. Five patients (7%) had minor side effects. Seven (10%) of 70 patients went on to have surgery. Complications after 30 days occurred in five patients (7%); two required repeated endoscopy with fragment extraction, two required placement of an endoprosthesis, and one died. We conclude that biliary extracorporeal shock-wave lithotripsy is valuable as an adjuvant to standard interventional techniques for removing bile duct stones.

  7. Clinical experience in applying endoscopic Nd:YAG laser to treat 451 esophagostenotic cases

    NASA Astrophysics Data System (ADS)

    Wang, Rui-Zhong; Wang, Zhen-he; Lu, Kuang-sheng; Yang, Xiao-zhi; Lu, Bo-kao

    1991-07-01

    This paper is to report and analyze our clinical experience in ap].ying endosoopi. c Nd:YAG laser to treat 451 esophagostenoses (1197 peraon times) including all kinds of then. All kinds of esophagostexiosis were mainly characterized by having difficulties swallowing foods. Some of their esophagus were even oompletely obstructed and could not drink even a drop of water On the basis of experint&xts in animals, fresh organs of the body, we started to treat all kinds of esophagostenosis with endoscopio Nd:YAG laser in 1985. By the end of 1989, 451 patients bad been treated in our hospital. Boh the patients and we felt satisfactory with the results we gain.

  8. Endoscopic mucosal incision by diode laser for early cancer treatment in the alimentary tract: effect of submucosal indocyanine green solution injection

    NASA Astrophysics Data System (ADS)

    Hayashi, Takuya; Arai, Tsunenori; Nakamura, Naoko; Tajiri, Hisao; Miura, Soichiro; Kikuchi, Makoto

    1999-06-01

    Mucosal incision technique by diode laser ablation was studied to ensure the operation of endoscopic mucosal resection (EMR), which is gold standard method for early gastric cancer with little/no risk of lymphnode metastasis. Our method was designed to facilitate grasping a large lesion by hitching the snaring wire on the incised mucosal groove around the lesion. We employed local submucosal injection of indocyanine green (ICG) solution. ICG solution was used to prevent direct laser light penetration to the muscularis propriae owing to strong absorption of 805nm light (absorption coefficent at 805 nm is about 200cm-1). We used diode laser radiation with an output of 25W by contact (0.1, 0.5, 1.0 kg/cm2) and non-contact irradiation methods. In the preliminary experiment with resected porcine stomach, muscularis propriae was intact by the 60s non-contact irradiation or the 8s contact irradiation with contact pressure of 1kg/cm2. In the endoscopic experiment we used 3 dogs. Using conical contact probe, we successfully demonstrated 3cm diameter circular incision with sharp groove in 10 minutes. We could place the snaring wire on the incised groove. Histology of the endoscopically incised canine stomach revealed that the submucosal layer welled up to 6mm in thickness and the bottom of the incision groove reached 1.9mm at deepest below the mucosal muscle. The thickness of the coagulation layer around the incised groove was up to 1.8mm. No damage was seen a the muscularis propriae. We demonstrate easy as well as sure snaring by using our laser incision technique. We think our technique may be available to enhance the efficacy of EMR for early gastric cancer including the lesion over 2cm in diameter.

  9. Treatment for intranasal synechiae by CO2 laser under endoscopic visualization

    NASA Astrophysics Data System (ADS)

    Feng, Yunhai; Yin, Shankai

    2005-07-01

    Endonasal low intensity laser therapy (ELILT) began in China in 1998. Now in China it is widely applied to treat hyperlipidemia and brain diseases such as Alzheimer's disease, Parkinson's disease, insomnia, poststroke depression, intractable headache, ache in head or face, cerebral thrombosis, acute ischemic cerebrovascular disease, migraine, brain lesion and mild cognitive impairment. There are four pathways mediating EILILT, Yangming channel, autonomic nervous systems and blood cells. Two unhealth acupoints of Yangming channal inside nose might mediate the one as is low intensity laser acupuncture. Unbalance autonomic nervous systems might be modulated. Blood cells might mediate the one as is intravascular low intensity laser therapy. These three pathways are integrated in ELILT so that serum amyloid β protein, malformation rate of erythrocyte, CCK-8, the level of viscosity at lower shear rates and hematocrit, or serum lipid might decrease, and melanin production/SOD activity or β endorphin might increase after ELILT treatment. These results indicate ELILT might work, but it need to be verified by randomized placebo-controlled trial.

  10. Uncovering the Secret of Shock Wave Lithotripsy

    NASA Astrophysics Data System (ADS)

    Zhong, P.

    Shock wave lithotripsy (SWL) is an engineering innovation that has revolutionized the treatment of kidney stone disease since the early 1980s [1] - [3]. Today, SWL is the first-line therapy for millions of patients worldwide with renal and upper urinary stones [3, 4].

  11. [Medical and Economic Aspects of Extracorporeal Shock Wave Lithotripsy].

    PubMed

    Knoll, T; Fritsche, H-M; Rassweiler, J

    2011-11-01

    Extracorporeal shock wave lithotripsy (ESWL) is the method of choice for most renal and ureteral calculi. However, endoscopic procedures such as ureteroscopy or percutaneous nephrolithotomy are being more and more performed as primary treatment alternatives in clinical routine. This development may result from the sometimes unsatisfying results of ESWL. While this is often explained by a lower efficacy of last-generation machines, an often unrecognized explanation is the impact of a less well trained urologist. To achieve best results it is mandatory that fundamental knowledge about shock wave physics and disintegration mechanisms are available. In Germany, the reimbursement system between outpatient and inpatient departments is totally separate. This leads to difficulties in clinical practice. We believe that patients at risk for complications, such as ureteral stones, urinary tract infections or high age, benefit from inpatient treatment, while uncomplicated renal stones can safely be treated on an outpatient basis. Regular application and training of ESWL will aid an optimization of its results and acceptance.

  12. A prospective randomized trial evaluating endoscopic Nd:YAG laser prostate ablation with or without potassium titanyl phosphate (KTP) laser bladder neck incision.

    PubMed

    Langley, S E; Gallegos, C R; Moisey, C U

    1997-12-01

    To investigate whether performing a potassium titanyl phosphate (KTP) laser bladder neck incision (BNI) in conjunction with a Nd:YAG endoscopic ablation of the prostate (ELAP) compared with an ELAP alone, improves early post-operative voiding rates and clinical outcome. A prospective randomized trial that was both double-blind and power-determined (80%) compared 88 patients with benign prostatic enlargement undergoing ELAP and those undergoing KTP BNI and ELAP. A dual-wavelength KTP/532TM (Laserscope) laser was used with Add/Stat side-firing fibres. A urethral catheter was inserted post-operatively and was removed after 18 h. Patients unable to void at this stage were then re-catheterized, discharged and readmitted 2 weeks later for catheter removal. Patients were followed up at 3 month intervals. Post-operatively, 80% of the patients undergoing KTP BNI and ELAP were able to void on catheter removal at 18 h, compared with only 57% of the patients undergoing ELAP alone (P < 0.05, chi-square). After 1 month, two patients from the former and four from the latter group failed to void and required further surgery. At 3 months, there was a significant improvement in the post-void residual volume, maximum flow rate, symptom and quality-of-life scores compared to the pre-operative values for both groups (P < 0.005). However, there was a greater improvement in the flow rate and symptom score in patients undergoing KTP BNI and ELAP (P < 0.05). This study shows the benefit of performing a KTP BNI with ELAP in terms of early voiding rates and initial clinical outcome, and this treatment is recommended.

  13. Dependence of calculus retropulsion dynamics on fiber size and radiant exposure during Ho:YAG lithotripsy.

    PubMed

    Lee, Ho; Ryan, Robert T; Kim, Jeehyun; Choi, Bernard; Arakeri, Navanit V; Teichman, Joel M H; Welch, A J

    2004-08-01

    During pulsed laser lithotripsy, the calculus is subject to a strong recoil momentum which moves the calculus away from laser delivery and prolongs the operation. This study was designed to quantify the recoil momentum during Ho:YAG laser lithotripsy. The correlation among crater shape, debris trajectory, laser-induced bubble and recoil momentum was investigated. Calculus phantoms made from plaster of Paris were ablated with free running Ho:YAG lasers. The dynamics of recoil action of a calculus phantom was monitored by a high-speed video camera and the laser ablation craters were examined with Optical Coherent Tomography (OCT). Higher radiant exposure resulted in larger ablation volume (mass) which increased the recoil momentum. Smaller fibers produced narrow craters with a steep contoured geometry and decreased recoil momentum compared to larger fibers. In the presence of water, recoil motion of the phantom deviated from that of phantom in air. Under certain conditions, we observed the phantom rocking towards the fiber after the laser pulse. The shape of the crater is one of the major contributing factors to the diminished recoil momentum of smaller fibers. The re-entrance flow of water induced by the bubble collapse is considered to be the cause of the rocking of the phantom.

  14. Combination of extracorporeal lithotripsy and flexible ureterorenoscopy optimize renal lithiasis therapy.

    PubMed

    Pérez-Lanzac, A; Parra-Serván, P; León-Delgado, C; Okhunov, Z; Lusch, A; Álvarez-Ossorio, J L

    2017-04-01

    Describe our initial experience in the treatment of renal lithiasis with extracorporeal lithotripsy controlled by simultaneous flexible ureterorenoscopy and combined with holmium laser lithotripsy. We performed this novel technique in a previously selected patient with left renal lithiasis, two in the superior calix, two in the medium calix and two in the inferior calix, the biggest of which was placed in medium calix and was 6mm long. We proceeded to an extracorporeal shock wave lithotripsy and a simultaneous flexible ureterorenoscopy for better controlling the fragmentation of the lithiasis with the use of a holmium laser. In the immediate post-operative, an ultrasound was performed and, one month later, a computerized tomography (CT) was done. The complete fragmentation of all the lithiasis was obtained and a double-J catheter was placed. After the assessment of the absence of stone fragments by CT the catheter was removed. No intra-operative or post-operative complications were described. The technique described is novel, safe and reproducible. The good result obtained through this combined technique increases our interest in continuing with its application and consider it as an option for the treatment of renal lithiasis in our patients. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. Minimizing endoscopic thoracic sympathectomy for primary palmar hyperhidrosis: guided by palmar skin temperature and laser Doppler blood flow.

    PubMed

    Li, Xu; Tu, Yuan-Rong; Lin, Min; Lai, Fan-Cai; Chen, Jian-Feng; Miao, Hui-Weng

    2009-02-01

    Limiting the extent of sympathectomy in palmar hyperhidrosis was recently recognized as an effective method to minimize the incidence and severity of troublesome compensatory sweating. However, the levels at which transection should be performed remain controversial. In this study, we proposed that the level of ablation varies and should be adjusted for each individual patient. Guided by palmar skin temperature and laser Doppler blood flow, we try to find the correct target level in each case. Fifty patients with severe primary palmar hyperhidrosis received bilateral endoscopic thoracic sympathectomy. Different levels of transection from T4 to T2 were performed step by step until the successful extirpation was implied by the intraoperative monitoring. The results of the operations were studied. All patients were followed up and evaluated for symptom resolution, postoperative complication, levels of satisfaction, and severity of compensatory sweating. Of a total of 100 lateral procedures, 76 laterals (76%) ended the procedure at the T4 level, 23 laterals (23%) ended the procedure at the T3 level, and 1 lateral (1%) ended the procedure at the T2 level. The postoperative complication was minor, and no Horner's syndrome was detected. The rate of symptom resolution was 100% and no recurrence was found. The satisfaction rate was 92%, and the incidence of mild, moderate, and severe compensatory sweating were 12%, 8%, and 6%, respectively. Concerning the sympathectomy for palmar hyperhidrosis, there is a possibility that the level of the transection varies and should be adjusted for each individual patient. Intraoperative monitoring of temperature and blood flow may be a useful tool in establishing a kind of standardized reference for finding the correct target level.

  16. Extracorporeal shockwave lithotripsy in pediatrics.

    PubMed

    D'Addessi, Alessandro; Bongiovanni, Luca; Sasso, Francesco; Gulino, Gaetano; Falabella, Roberto; Bassi, Pierfrancesco

    2008-01-01

    Since its introduction in 1980, extracorporeal shockwave lithotripsy (SWL) has become the first therapeutic option in most cases of upper-tract urolithiasis, and the technique has been used for pediatric renal stones since the first report of success in 1986. Lithotripter effectiveness depends on the power expressed at the focal point. Closely correlated with the power is the pain produced by the shockwaves. By reducing the dimensions of the focus, it becomes possible to treat the patient without anesthesia or analgesia but at the cost of a higher re-treatment rate. Older children often tolerate SWL under intravenous sedation, and minimal anesthesia is applicable for most patients treated with second- and third-generation lithotripters. Ureteral stenting before SWL has been controversial. Current data suggest that preoperative stent placement should be reserved for a few specific cases. Stone-free rates in pediatric SWL exceed 70% at 3 months, with the rate reaching 100% in many series. Even the low-birth-weight infant can be treated with a stone-free as high as 100%. How can one explain the good results? Possible explanations include the lesser length of the child's ureter, which partially compensates for the narrower lumen. Moreover, the pediatric ureter is more elastic and distensible, which facilitates passage of stone fragments and prevents impaction. Another factor is shockwave reproduction in the body: there is a 10% to 20% damping of shockwave energy as it travels through 6 cm of body tissue, so the small body volume of the child allows the shockwaves to be transmitted with little loss of energy. There are several concerns regarding the possible detrimental effect of shockwaves on growing kidneys. Various renal injures have been documented with all type of lithotripters. On the other hand, several studies have not shown adverse effects. In general, SWL is considered to be the method of choice for managing the majority of urinary stones in children of all

  17. Thulium Laser Endoscopic En Bloc Enucleation of Nonmuscle-Invasive Bladder Cancer.

    PubMed

    Migliari, Roberto; Buffardi, Andrea; Ghabin, Hassan

    2015-11-01

    To evaluate if thulium laser enucleation of bladder tumor (ThuLEBT) offers any advantage over monopolar resection of nonmuscle-invasive bladder cancer (NMIBC) without increasing complications. From February 2012 to September 2013, 58 patients (41 males and 17 females) newly diagnosed with having a single papillary bladder tumor more than 1 cm in diameter were selected for this prospective study on ThuLEBT. A similar historical cohort of 61 patients who underwent traditional monopolar resection (TURB-T) of NMIBC (Group B) was used to compare the two procedures. Mean tumor diameter in the ThuLEBT group was 2.5 cm (range 0.5-4.5). Mean operative time was 25 minutes (range 12-30). Re-resection and cold cup biopsy of the tumor base (in 90 days) were negative for bladder cancer (BC) persistence or recurrence in all patients with NMIBC treated with ThuLEBT. In Group B, seven patients were found with disease persistence. In eight cases of TURB-T patients, no detrusor muscle was identified, while it was always easily identified in the ThuLEBT group. No patient in Group A experienced obturator nerve reflection intraoperatively and no bladder perforation was evidenced in dome-located neoplasm; when involved, ureteral meatus was sharply excised without subsequent postoperative evidence of distortion. No significant intraoperative or postoperative bleeding occurred in all but one patient in the two groups. ThuLEBT may represent a potential alternative to TURB-T, which nowadays is considered the standard for diagnosis and treatment of NMBIC. In our study, ThuLEBT allowed accurate reporting of neoplastic depth invasion, suggesting the possibility to avoid a second-look resection at 90 days. All the different intravesical sites of the BC may be enucleated with the thulium laser, which offers advantages over the monopolar energy, especially when the tumor is located in the lateral bladder wall, at the bladder dome, or in the perimeatal zone.

  18. The Acoustics of Shock Wave Lithotripsy

    NASA Astrophysics Data System (ADS)

    Cleveland, Robin O.

    2007-04-01

    The shock waves employed in lithotripsy are high amplitude acoustics waves. As they propagate through the body to the stone that are affected by coupling to the body and the presence of tissue through which they must pass. Once the shock wave arrives at the stone there is a complex transmission of energy into the stone as the shock wave can couple into compression and shear waves in the stone and produce cavitation in the surrounding fluid. The surrounding tissue is also subject to large physical forces that can result in damage. Physical phenomena that play a role include: generation of sound, nonlinear distortion, attenuation, diffraction, coupling into the body, transmission and mode conversion into the stone. This paper gives a synopsis of some of the relevant physics that applies to shock wave lithotripsy.

  19. Optimizing Shock Wave Lithotripsy: A Comprehensive Review

    PubMed Central

    McClain, Paul D; Lange, Jessica N; Assimos, Dean G

    2013-01-01

    Shock wave lithotripsy is a commonly used procedure for eradicating upper urinary tract stones in patients who require treatment. A number of methods have been proposed to improve the results of this procedure, including proper patient selection, modifications in technique, adjunctive therapy to facilitate elimination of fragments, and changes in lithotripter design. This article assesses the utility of these measures through an analysis of contemporary literature. PMID:24082843

  20. [Ureterorenoscopy combined with extracorporeal shockwave lithotripsy].

    PubMed

    González Cabrera, L A; Oro Ortiz, J

    1989-01-01

    In May 1986, extracorporeal shock wave lithotripsy and endourologic procedures became available in the treatment of lithiasis at the "Hermanos Ameijeiras" Hospital. The present study describes our experience and the results achieved during a 12-month period using endourologic procedures. During this period 65 URS procedures were performed to treat post-ESWL ureteral obstruction, and 22 to push the stone up to the kidney for subsequent ESWL treatment.

  1. Endoscopic septoplasty.

    PubMed

    Getz, Anne E; Hwang, Peter H

    2008-02-01

    Successful septoplasty involves accurate assessment of septal pathology and sound technique to avoid persistent symptoms and new complications. This review highlights endoscopic septoplasty techniques and instrumentation, as well as the indications for and advantages of endoscopic septoplasty as compared with traditional headlight septoplasty. Isolated lesions such as septal spurs and contact points may be better addressed with limited endoscopic techniques. Powered instrumentation has been utilized with reported success. Operative time and outcomes of endoscopic septoplasty are at least commensurate with, and at times superior to, traditional techniques. Endoscopic technology greatly enhances visualization during septoplasty. Discrete septal pathologies such as isolated deflection, spurs, perforations, and contact points can be addressed in a directed fashion. These advantages can be especially important in revision cases. Endoscopic technique in conjunction with video imaging is valuable for the education of residents and staff.

  2. Selective mucosal ablation using CO2 laser for the development of novel endoscopic submucosal dissection: comparison of continuous wave and nanosecond pulsed wave

    NASA Astrophysics Data System (ADS)

    Ishii, K.; Watanabe, S.; Obata, D.; Hazama, H.; Morita, Y.; Matsuoka, Y.; Kutsumi, H.; Azuma, T.; Awazu, K.

    2010-02-01

    Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment technique for small early gastric cancers. Procedures are carried out using some specialized electrosurgical knifes with a submucosal injection solution. However it is not widely used because its procedure is difficult. The objective of this study is to develop a novel ESD method which is safe in principle and widely used by using laser techniques. In this study, we used CO2 lasers with a wavelength of 10.6 μm for mucosal ablation. Two types of pulse, continuous wave and pulsed wave with a pulse width of 110 ns, were studied to compare their values. Porcine stomach tissues were used as a sample. Aqueous solution of sodium hyaluronate (MucoUpR) with 50 mg/ml sodium dihydrogenphosphate is injected to a submucosal layer. As a result, ablation effect by CO2 laser irradiation was stopped because submucosal injection solution completely absorbed CO2 laser energy in the invasive energy condition which perforates a muscle layer without submucosal injection solution. Mucosal ablation by the combination of CO2 Laser and a submucosal injection solution is a feasible technique for treating early gastric cancers safely because it provides a selective mucosal resection and less-invasive interaction to muscle layer.

  3. How to improve lithotripsy and chemolitholysis of brushite-stones: an in vitro study.

    PubMed

    Heimbach, D; Jacobs, D; Hesse, A; Müller, S C; Zhong, P; Preminger, G M

    1999-08-01

    Because of their resistance to fragmentation, treatment of brushite stones is a big problem. This study was performed to look for an improvement in therapeutic strategies by using artificial stones made of brushite (Bon(n)-stones), which are comparable to their natural counterparts. Using an ultrasound transmission technique, longitudinal wave propagation speeds were measured at different time intervals during treatment with hemiacidrin. From these and density measurements, transverse wave speed, wave impedance and dynamic mechanical properties of the artificial stones were calculated. Moreover, the microhardness of artificial stones was measured and investigations on shock wave lithotripsy (SWL) combined with initial chemolytic treatment of the stones were performed. The suggestion was confirmed that stone fragility and thus SWL can be improved by varying the physical properties of brushite stones through treatment with hemiacidrin. Additionally, we demonstrated the efficacy of Suby G in dissolving artificial brushite stones using an experimental arrangement simulating the physiological conditions in the upper urinary tract. Moreover, the efficacy of four different intracorporeal lithotripsy devices (electrohydraulic, pneumatic, laser and ultrasound) was tested and it was shown that electrohydraulic lithotripsy seems to be the best system for comminution of brushite stones.

  4. Massive steinstrasse without lithotripsy: a rare case report

    PubMed Central

    Abdulmajed, Mohamed Ismat; Anandaram, Pallavoor Sudarsanam; Wyn Jones, Vaughan; Shergill, Iqbal Singh

    2013-01-01

    The accumulation of ureteric stone fragments causing ureteric blockage is known as ‘Steinstrasse’ or ‘Stone Street’ and is usually described as a complication of shock-wave lithotripsy (SWL). We herein present a rare case of massive Steinstrasse in a young male patient with no previous history of urolithiasis or lithotripsy. PMID:26328081

  5. [Treatment of renoureteral lithiasis using extracorporeal shockwave lithotripsy. Experience in Cuba].

    PubMed

    Larrea Masvidal, E; García Serrano, C; Hernández Silverio, D; Castillo Rodríguez, M; Casals Armada, J; Valdés Gómez, C; Báez Hernández, D

    1989-01-01

    Herein we present our experience in 5,000 cases of reno-ureteral lithiasis submitted to treatment at the Extracorporeal Lithotripsy Unit of Hermanos Ameijeiras Hospital in Havana, Cuba, from April 1986 and during a period spanning 30 months. Treatment was exclusively by extracorporeal shock wave lithotripsy (ESWL) in 85.5% of the patients and in combination with other procedures in 14.5% (endoscopic maneuvers in 5.9%, percutaneous nephrostomy 4.4%, open surgery 3.6%, and percutaneous nephrolithotripsy 0.6%). Complications were observed in 7% of the cases: ureteric obstruction (6.4%) with or without infection, perirenal hematoma (0.4%), and obstructive anuria (0.2%); acute urinary infection of different clinical types, some of which were very severe, were observed concomitantly in 2.6% of these patients. Two months following treatment, 86% of the cases were completely stone-free. At 6 months 96.2% were completely stone-free; the remaining 3.8% were classed as residual lithiasis. The pathologic conditions that put patients at high therapeutic risk and the possible complications that could arise were identified. The efficacy of the Dornier HM-3 lithotripter and the health care system that permits its extensive use are highlighted.

  6. The efficacy and safety of the flexible fiber CO2 laser delivery system in the endoscopic management of pediatric airway problems: Our long term experience.

    PubMed

    Lee, Gi Soo; Irace, Alexandra; Rahbar, Reza

    2017-06-01

    To report the use of flexible fiber CO2 laser in the endoscopic management of pediatric airway cases. A retrospective review was conducted of patients who underwent CO2 laser-assisted airway procedures between September 2007 and January 2014 at a tertiary pediatric hospital. Sixty-eight patients underwent 80 procedures utilizing flexible fiber CO2 laser. Procedures included supraglottoplasty (n = 32), laryngeal cleft repair (type I [n = 10], type II [n = 7], type III [n = 6]), suprastomal granuloma excision (n = 6), cordotomy (n = 4), laryngeal neurofibroma excision (n = 4), laryngeal granulomatous mass excision (n = 1), subglottic stenosis excision (n = 6), division of glottic web (n = 2), subglottic cyst excision (n = 1), and supraglottic biopsy (n = 1). Ages ranged from 8 days to 21 years (median 11 months). No intraoperative or postoperative complications related to the use of laser were noted. The flexible fiber CO2 laser can be safely and effectively used to address a variety of pediatric airway lesions. Previously, the use of CO2 laser in minimally invasive airway surgery has been limited due to the articulating arm carrier, absence of a hand piece, and the direct line-of sight view required. The fiber allows the cutting beam to be directed at the site of the lesion and bypasses limitations posed by other laser systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Endoscopic septoplasty.

    PubMed

    Sautter, Nathan B; Smith, Timothy L

    2009-04-01

    Endoscopic septoplasty has gained popularity since Lanza and colleagues and Stammberger first described the technique. This technique has several advantages over the traditional "headlight" septoplasty. These advantages include superior visualization, accommodation of limited and minimally invasive septoplasty, and usefulness as an effective teaching tool. This article reviews and illustrates the endoscopic septoplasty technique and discusses its limitations and advantages.

  8. Outcome of probe-based confocal laser endomicroscopy (pCLE) during endoscopic retrograde cholangiopancreatography: A single-center prospective study in 45 patients

    PubMed Central

    Lönnebro, Ragnar; Stigliano, Serena; Haas, Stephan L; Swahn, Fredrik; Enochsson, Lars; Noel, Rozh; Segersvärd, Ralf; Chiaro, Marco Del; Verbeke, Caroline S; Arnelo, Urban

    2015-01-01

    Background Diagnosis of pre-malignant and malignant lesions in the bile duct and the pancreas is sometimes cumbersome. This applies in particular to intraductal papillary mucinous neoplasia (IPMN) and bile duct strictures in primary sclerosing cholangitis (PSC). Aims To evaluate in a prospective cohort study the sensitivity and specificity of probe-based confocal laser microscopy (pCLE) during endoscopic retrograde cholangiopancreatography (ERCP). Methods We performed pCLE together with mother-baby endoscopy (SpyGlass) during 50 ERCP sessions in 45 patients. The Miami and Paris criteria were applied. Clinical diagnosis via imaging was compared to pCLE and the final pathological diagnosis from surgically-resected, biopsy, or cytology specimens. Patients were followed up for at least 1 year. Results We were able to perform pCLE in all patients. Prior to endoscopy, the diagnosis was benign in 23 patients and undetermined (suspicious) in 16 patients, while six patients had an unequivocal diagnosis of malignancy. Sensitivity was 91% and specificity 52%. The positive (PPV) and negative predictive value (NPV) was 82% and 100%, respectively. Apart from mild post-ERCP pancreatitis in two patients, no complications occurred. Conclusions Our study showed that pCLE is a safe, expert endoscopic method with high technical feasibility, high sensitivity and high NPV. It provided diagnostic information that can be helpful for decisions on patient management, especially in the case of IPMN and unclear pancreatic lesions, in individuals whom are at increased risk for pancreatic cancer. PMID:26668748

  9. Fabrication of a chirped artificial compound eye for endoscopic imaging fiber bundle by dose-modulated laser lithography and subsequent thermal reflow

    NASA Astrophysics Data System (ADS)

    Deng, Shengfeng; Lyu, Jinke; Sun, Hongda; Cui, Xiaobin; Wang, Tun; Lu, Miao

    2015-03-01

    A chirped artificial compound eye on a curved surface was fabricated using an optical resin and then mounted on the end of an endoscopic imaging fiber bundle. The focal length of each lenslet on the curved surface was variable to realize a flat focal plane, which matched the planar end surface of the fiber bundle. The variation of the focal length was obtained by using a photoresist mold formed by dose-modulated laser lithography and subsequent thermal reflow. The imaging performance of the fiber bundle was characterized by coupling with a coaxial light microscope, and the result demonstrated a larger field of view and better imaging quality than that of an artificial compound eye with a uniform focal length. Accordingly, this technology has potential application in stereoscopic endoscopy.

  10. Superior Mesenteric Artery Dissection after Extracorporeal Shockwave Lithotripsy

    PubMed Central

    Bakoyiannis, Christos; Anastasiou, Ioannis; Koutsoumpelis, Andreas; Fragiadis, Evangelos; Felesaki, Eleni; Kafeza, Marina; Georgopoulos, Sotirios; Tsigris, Christos

    2012-01-01

    The use of shockwave lithotripsy is currently the mainstay of treatment in renal calculosis. Several complications including vessel injuries have been implied to extracorporeal shockwave lithotripsy. We report an isolated dissection of the superior mesenteric artery in a 60-year-old male presenting with abdominal pain which occurred three days after extracorporeal shockwave lithotripsy. The patient was treated conservatively and the abdominal pain subsided 24 hours later. The patient's history, the course of his disease, and the timing may suggest a correlation between the dissection and the ESWL. PMID:23304627

  11. Endoscopic ultrasound

    MedlinePlus

    ... Pancreatitis References Lee LS. Endoscopic ultrasound. In: McNalley PR, ed. GI/Liver Secrets Plus . 5th ed. Philadelphia, ... member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www. ...

  12. Patient and personnel exposure during extracorporeal lithotripsy.

    PubMed

    Glaze, S; LeBlanc, A D; Bushong, S C; Griffith, D P

    1987-12-01

    Extracorporeal shock wave lithotripsy (ESWL) has provided a nonsurgical approach to treatment of renal stones. The Dornier lithotripter uses dual image intensified x-ray systems to center the stone before treatment. Three imaging modes are offered: a fluoroscopic mode and two video spot filming modes. The average entrance exposure to the stone side of the typical patient at our facility is 2.6 X 10(-3) C kg-1 (10 R) [range: 0.5-7.7 X 10(-3) C kg-1 (2-30 R)] which is comparable and often much less than that reported for percutaneous lithotripsy. Recommendations are made for minimizing patient exposure. Scattered radiation levels in the lithotripter room are presented. We have determined that Pb protective apparel is not required during this procedure provided x-ray operation is temporarily halted should personnel be required to lean directly over the tub to attend to the patient. If the walls of the ESWL room are greater than 1.83 m (6 feet) from the tub, shielding in addition to conventional construction is not required.

  13. Patient and personnel exposure during extracorporeal lithotripsy

    SciTech Connect

    Glaze, S.; LeBlanc, A.D.; Bushong, S.C.; Griffith, D.P.

    1987-12-01

    Extracorporeal shock wave lithotripsy (ESWL) has provided a nonsurgical approach to treatment of renal stones. The Dornier lithotripter uses dual image intensified x-ray systems to center the stone before treatment. Three imaging modes are offered: a fluoroscopic mode and two video spot filming modes. The average entrance exposure to the stone side of the typical patient at our facility is 2.6 X 10(-3) C kg-1 (10 R) (range: 0.5-7.7 X 10(-3) C kg-1 (2-30 R)) which is comparable and often much less than that reported for percutaneous lithotripsy. Recommendations are made for minimizing patient exposure. Scattered radiation levels in the lithotripter room are presented. We have determined that Pb protective apparel is not required during this procedure provided x-ray operation is temporarily halted should personnel be required to lean directly over the tub to attend to the patient. If the walls of the ESWL room are greater than 1.83 m (6 feet) from the tub, shielding in addition to conventional construction is not required.

  14. [The history of extracorporeal shockwave lithotripsy in Spain].

    PubMed

    Ruíz Marcellán, Francisco Javier; Ibarz Servio, Luis

    2007-10-01

    We give a historical outline of urinary lithiasis with emphasis in the alternative therapeutic options to surgery. We expose the previous steps that led to the birth of extracorporeal shockwave lithotripsy and its implementation in our country.

  15. Statistical Case Study of Extracorporeal Shock Wave Lithotripsy

    DTIC Science & Technology

    2007-11-02

    Shock Wave Lithotripsy (ESWL) is one of the recent, most common ways of treating patients with urinary (renal and ureteric) stones through non...Page 1 of 3 Statistical Case Study of Extracorporeal Shock Wave Lithotripsy Hani M. Amasha1 and Basel M. Al-Eideh2 1Department of...invasive destruction of stones [1]. Many reports and studies have shown its safety and success. It offers the patient less pain; much less discomfort and

  16. Axial-Stereo 3-D Optical Metrology for Inner Profile of Pipes Using a Scanning Laser Endoscope.

    PubMed

    Gong, Yuanzheng; Johnston, Richard S; Melville, C David; Seibel, Eric J

    As the rapid progress in the development of optoelectronic components and computational power, 3D optical metrology becomes more and more popular in manufacturing and quality control due to its flexibility and high speed. However, most of the optical metrology methods are limited to external surfaces. This paper proposed a new approach to measure tiny internal 3D surfaces with a scanning fiber endoscope and axial-stereo vision algorithm. A dense, accurate point cloud of internally machined threads was generated to compare with its corresponding X-ray 3D data as ground truth, and the quantification was analyzed by Iterative Closest Points algorithm.

  17. Axial-Stereo 3-D Optical Metrology for Inner Profile of Pipes Using a Scanning Laser Endoscope

    PubMed Central

    Gong, Yuanzheng; Johnston, Richard S.; Melville, C. David; Seibel, Eric J.

    2015-01-01

    As the rapid progress in the development of optoelectronic components and computational power, 3D optical metrology becomes more and more popular in manufacturing and quality control due to its flexibility and high speed. However, most of the optical metrology methods are limited to external surfaces. This paper proposed a new approach to measure tiny internal 3D surfaces with a scanning fiber endoscope and axial-stereo vision algorithm. A dense, accurate point cloud of internally machined threads was generated to compare with its corresponding X-ray 3D data as ground truth, and the quantification was analyzed by Iterative Closest Points algorithm. PMID:26640425

  18. A comparison of Stone Cone versus lidocaine jelly in the prevention of ureteral stone migration during ureteroscopic lithotripsy

    PubMed Central

    Bastawisy, Mohamed; Gameel, Tarek; Radwan, Mohamed; Ramadan, Ahmed; Alkathiri, Mutie; Omar, Adel

    2011-01-01

    Background: Intracorporeal lithotripsy modalities and stone removal devices have been created to facilitate endoscopic management of ureteral stones. These devices, along with improved techniques, have resulted in stone-free rates greater than 95% with low morbidity. However, problems remain that preclude consistent 100% stone-free rates with endoscopic treatment of ureteral calculi. Retrograde migration during ureteroscopic procedures remains a significant problem. Objectives: The aim of this study was to compare the Stone Cone device and instillation of lubricating lidocaine jelly as two methods to prevent retrograde stone migration during ureteroscopic lithotripsy. Patients and methods: This study included patients suffering from ureteral stones that were treated with intracorporeal lithotripsy using the pneumatic Lithoclast. These patients were divided into two groups. In group I, the Stone Cone device was used, while in group II, lidocaine jelly 2% concentration was used. Results: This study included 40 patients with a mean age of 38.6 ± 9.3 years (20 patients in each group). There was no significant difference between the groups with regards to stone site, size or state of the upper urinary tract by excretory urography. The pneumatic Lithoclast allowed successful fragmentation of all calculi into small fragments. Upward stone migration did not occur in patients in the Stone Cone group, while in the lidocaine jelly group it occurred in three patients (15%). The operative time in the Stone Cone group ranged between 30 and 55 minutes (mean, 41.8 ± 5.3), while in the lidocaine jelly group it ranged between 40 and 71 minutes (mean, 51.4 ± 3.4), and this difference was statistically significant (p < 0.05). Conclusion: The Stone Cone is safe and efficient in preventing proximal stone migration during ureteroscopic pneumatic lithotripsy. It maintained continuous ureteral access and demonstrated a statistically significant advantage over the

  19. Does extracorporeal shockwave lithotripsy cause hypertension?

    PubMed

    Montgomery, B S; Cole, R S; Palfrey, E L; Shuttleworth, K E

    1989-12-01

    Several series have suggested that the incidence of hypertension following extracorporeal shockwave lithotripsy (ESWL) may be as high as 8%. In this study, changes in blood pressure and the incidence of hypertension have been observed in 733 patients 12 to 44 months after renal ESWL on the Dornier HM3. The incidence of hypertension following ESWL was 8.1%. In patients with a pre-ESWL diastolic pressure less than 90 mmHg, the incidence of those with a diastolic greater than or equal to 100 mm Hg post-operatively was significantly greater than that predicted by historical data. There was no overall change in the mean blood pressure of the group. The hypertensive risk of ESWL remains unclear. However, blood pressure surveillance should be performed following ESWL and a prospective study is required.

  20. Holmium:YAG surgical lasers.

    PubMed

    1995-03-01

    "Holmium:YAG (Ho:YAG)" is the shorthand name for a family of solid-state lasers that use the doping element holmium in a laser crystal (e.g., YAG [yttrium-aluminum-garnet]) and that emit energy at approximately 2.1 microns. This wavelength is relatively new to medicine and has been used in laser surgery for only about the last six years. Like the carbon dioxide (CO2) laser when it was first used clinically, the Ho:YAG laser is poised for rapid and wide-spread use. Ho:YAG lasers, like CO2 lasers, offer precise cutting with minimal damage to adjacent tissue; however, unlike CO2 lasers, they also offer fiberoptic delivery (which is ideal for endoscopic use) and the ability to treat tissue in a liquid-filled environment (e.g., saline, blood). The initial specialty for which the Ho:YAG laser was used was arthroscopic surgery, especially diskectomy. Today, it is effectively used in many surgical specialties, including general surgery, urology, laparoscopy, neurosurgery, lithotripsy, angioplasty, orthopedic surgery (which includes procedures such as meniscectomy, bone sculpting [may also be performed in plastic surgery], and some experimental surgery, such as cartilage shrinking to tighten loose joints), and dentistry. Because of its broad range of potential applications, it has been called the "Swiss Army Knife" of lasers. High-powered Ho:YAG lasers, which enable surgeons to work more quickly and cut more smoothly, have been made available only within the last three years (units offering > 20 W) to 18 months (units offering > 60 W). Because of this rapid increase, high-powered units are still relatively expensive, and it is not yet clear whether maximum power outputs will continue to increase or whether the cost of higher-power units will begin to come down. Although low-power and high-power Ho:YAG lasers can be used for the same procedures, their different ranges of possible clinical techniques make them better suited to different applications: low-power units are

  1. [Lithotripsy of gallbladder calculi with extracorporeal shockwaves].

    PubMed

    Nogueira, C E; Martins, F P; Dani, R

    1991-01-01

    Two hundred and sixty two patients with gallbladder stones were prospectively evaluated at the Biliary Lithiasis Treatment Unit of the Mater Dei Hospital, Belo Horizonte, MG., and 45 (17.5%) were selected for extracorporal shock wave lithotripsy (ECSWL). From these, 32 were submitted to the procedure. One stone was present in 30 patients, 2 stones in another and 1 patient had 3 stones. The mean diameter was 14.7 mm ranging from 8 to 28 mm. ECSWL was preceded by 1 week course of ursodeoxycholic acid (8 to 10 mg/dk/day) and this medication was continued after the procedure. ECSWL was done with the Lithosthar-Plus apparatus (Siemens). Meperidine (up to 100 mg) IM and pirazolene IV was given when necessary. The intensity of the shock waves was gradually increased to a maximum (9 bar) whenever tolerated. The treatment was well succeeded in 22 cases (71%) with pulverization in 12 (38.7%). In 9 patients (29%) remaining fragments were greater than 4 mm. From these, 3 were submitted to a second session of ECSWL. In 1 patient the stone could not be properly positioned for lithotripsy. The mean number of shock waves was 2,591, ranging from 801 to 4,411. The mean duration of the sessions was 80 min, ranging from 45 to 150 min. In 3 patients, a complete disappearance of fragments was observed in intervals of 1 to 6 months after the procedure. One patient had severe pain during ECSWL and developed acute cholecystitis. One patient had sinus bradycardia. One patient with total stone pulverization, become jaundiced 1 month after ECSWL and a gallbladder carcinoma was found at surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Endoscopic calcaneoplasty.

    PubMed

    Jerosch, Joerg

    2015-03-01

    Opinions differ regarding the surgical treatment of posterior calcaneal exostosis. After failure of conservative treatment, open surgical bursectomy and resection of the calcaneal prominence is indicated by many investigators. Clinical studies have shown high rates of unsatisfactory results and complications. Endoscopic calcaneoplasty (ECP) is a minimally invasive surgical option that can avoid some of these obstacles. ECP is an effective procedure for the treatment of patients with posterior calcaneal exostosis. The endoscopic exposure is superior to the open technique and has less morbidity, less operating time, fewer complications, and the disorders can be better differentiated.

  3. Update on lasers in urology 2014: current assessment on holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripter settings and laser fibers.

    PubMed

    Kronenberg, Peter; Traxer, Olivier

    2015-04-01

    The purpose of the study was to review the existing literature on holmium:yttrium-aluminum-garnet laser lithotripsy regarding lithotripter settings and laser fibers. An online search of current and past peer-reviewed literature on holmium laser lithotripsy was performed on several databases, including PubMed, SciElo, and Google Scholar. Relevant studies and original articles about lithotripter settings and laser fibers were examined, and the most important information is summarized and presented here. We examine how the choice of lithotripter settings and laser fibers influences the performance of holmium laser lithotripsy. Traditional laser lithotripter settings are analyzed, including pulse energy, pulse frequency, and power levels, as well as newly developed long-pulse modes. The impact of these settings on ablation volume, fragment size, and retropulsion is also examined. Advantages of small- and large-diameter laser fibers are discussed, and controversies are highlighted. Additionally, the influence of the laser fiber is examined, specifically the fiber tip preparation and the lithotripter settings' influence on tip degradation. Many technical factors influence the performance of holmium laser lithotripsy. Knowing and understanding these controllable parameters allows the urologist to perform a laser lithotripsy procedure safely, efficiently, and with few complications.

  4. In vivo visualization of epidermal growth factor receptor and survivin expression in porcine pancreas using endoscopic ultrasound guided fine needle imaging with confocal laser-induced endomicroscopy.

    PubMed

    Nakai, Y; Shinoura, S; Ahluwalia, A; Tarnawski, A S; Chang, K J

    2012-12-01

    The aims of this pilot study were to establish a principle of molecular imaging of the pancreas and determine in vivo expression of epidermal growth factor receptor (EGF-R) and survivin using a novel endoscopic ultrasound-guided fine needle imaging (EUS-FNI) technique, which incorporates needle based confocal laser-induced endomicroscopy (nCLE) after intrapancreatic injection of FTIC-labeled antibodies. Studies were performed in anesthetized pigs. FITC-labeled specific antibodies against EGF-R and survivin were injected into the tail and neck of the pancreas using a 19 gauge needle introduced under EUS guidance. Thirty minutes later, nCLE was performed using a prototype needle-based confocal laser-induced endomicroscopy probe (Cellvizio AQ-Flex-19, Mauna Kea Technologies, Paris, France) to determine cellular and tissue localization of EGF-R and survivin in the pancreas. Then pigs were euthanized and specimens of pancreas from areas injected with antibodies were obtained for histologic examination under epifluorescence microscope. EUS-guided nCLE enabled visualization of EGF-R and survivin in pancreatic tissue. Expression of EGF-R and survivin in pancreas was confirmed by histology. EGF-R immunoreactivity was localized to majority of duct-lining cells and to the surface and cytoplasm of many acinar cells. Survivin was localized mainly to the acinar cells. This study demonstrated the feasibility of in vivo, real time visualization of EGF-R and survivin in the pancreas by local injection of FITC-labeled antibodies via EUS-guided fine needle injection, followed by EUS-guided needle based confocal laser-induced endomicroscopy.

  5. Retained bile duct stones in a patient with Billroth II gastrectomy: extracorporeal shock wave lithotripsy and papillary dilatation via T tube.

    PubMed Central

    Nitsche, R; Fölsch, U R

    1991-01-01

    A postoperative T tube cholangiogram after cholecystectomy in a 62 year old patient showed two retained calculi of 14 mm diameter each. Endoscopic sphincterotomy was not possible because of previous Billroth II gastrectomy. The stones were disintegrated by electromagnetically generated extracorporeal shock waves. The T tube was replaced by a balloon catheter and the papilla of Vater was dilatated allowing passage of stone fragments. We conclude that retained bile duct stones can be removed without sphincterotomy or percutaneous extraction by extracorporeal shock wave lithotripsy and papillary dilatation. This method should be considered especially in patients with Billroth II gastrectomy. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:2013432

  6. Thulium fiber laser for the use in low-invasive endoscopic and robotic surgery of soft biological tissues

    NASA Astrophysics Data System (ADS)

    Michalska, M.; Brojek, W.; Rybak, Z.; Sznelewski, P.; Mamajek, M.; Gogler, S.; Swiderski, J.

    2016-12-01

    An all-fiber, diode-pumped, continuous-wave Tm3+-doped fiber laser operated at a wavelength of 1.94 μm was developed. 37.4 W of output power with a slope efficiency as high as 57% with respect to absorbed pump power at 790 nm was demonstrated. The laser output beam quality factor M2 was measured to be 1.2. The output beam was very stable with power fluctuations <1% measured over 1 hour. The laser system is to be implemented as a scalpel for surgery of soft biological tissues.

  7. Combined percutaneous and transurethral lithotripsy for forgotten ureteral stents with giant encrustation.

    PubMed

    Rabani, Seyed Mohammadreza

    2012-01-01

    Ureteral stents are widely used in many urologic practices. However, stents can cause significant complications including migration, fragmentation, and encrustation and it may possibly be forgotten. Successful management of a retained, encrusted stent requires combined endourological approaches. To present our experience with the approaches for treating forgotten ureteral stents associated with giant stone formation. Seventy four patients with forgotten ureteral stents were managed by different open (nephrolithotomy and/or cystolithotomy), or endoscopic procedures in our center. Among these, 11 patients had severe encrustation (stones larger than 35 mm within the bladder or kidney) and seven patients of this group, presented at our department between July 2007 and December 2010. Combined endourological procedures percutaneous nephrolithotripsy (PCNL), cystolithotripsy (CLT), transurethral lithotripsy (TUL) were performed in one or 2 separate sessions. In these 7 patients the whole of the stents, especially both ends were encrusted. Initially, cystolithotripsy, retrograde ureteroscopy and TUL were performed in the dorsal lithotomy position. Following this, a gentle attempt was made to retrieve the stent with the help of an ureteroscopic grasper. In some cases the stent was grasped by a hemostat clamp out of the urethral meatus with a gentle traction to facilitate lithotripsy in the ureter and even in the kidney. Finally, a ureteric catheter was placed adjacent to the stent for injection of radio-contrast material to delineate the renal pelvis and the calyces. Then in the same session or later in another session the patient was placed in the prone position and PCNL of the upper coil of the encrusted stent along with calculus was done and the stent was removed. In 5 out of seven patients, the initial indication for stent placement was for urinary stone disease after open nephrolithotomy and pyeloplasty in other centers and in two patients after TUL. All patients

  8. Combined Percutaneous and Transurethral Lithotripsy for Forgotten Ureteral Stents With Giant Encrustation

    PubMed Central

    Rabani, Seyed Mohammadreza

    2012-01-01

    Background Ureteral stents are widely used in many urologic practices. However, stents can cause significant complications including migration, fragmentation, and encrustation and it may possibly be forgotten. Successful management of a retained, encrusted stent requires combined endourological approaches. Objectives To present our experience with the approaches for treating forgotten ureteral stents associated with giant stone formation. Patients and Methods Seventy four patients with forgotten ureteral stents were managed by different open (nephrolithotomy and/or cystolithotomy), or endoscopic procedures in our center. Among these, 11 patients had severe encrustation (stones larger than 35 mm within the bladder or kidney) and seven patients of this group, presented at our department between July 2007 and December 2010. Combined endourological procedures percutaneous nephrolithotripsy (PCNL), cystolithotripsy (CLT), transurethral lithotripsy (TUL) were performed in one or 2 separate sessions. In these 7 patients the whole of the stents, especially both ends were encrusted. Initially, cystolithotripsy, retrograde ureteroscopy and TUL were performed in the dorsal lithotomy position. Following this, a gentle attempt was made to retrieve the stent with the help of an ureteroscopic grasper. In some cases the stent was grasped by a hemostat clamp out of the urethral meatus with a gentle traction to facilitate lithotripsy in the ureter and even in the kidney. Finally, a ureteric catheter was placed adjacent to the stent for injection of radio-contrast material to delineate the renal pelvis and the calyces. Then in the same session or later in another session the patient was placed in the prone position and PCNL of the upper coil of the encrusted stent along with calculus was done and the stent was removed. Results In 5 out of seven patients, the initial indication for stent placement was for urinary stone disease after open nephrolithotomy and pyeloplasty in other

  9. Extracorporeal Shock Wave Lithotripsy for Management of Residual Stones after Ureterolithotripsy versus Mini-Percutaneous Nephrolithotomy: A Retrospective Study

    PubMed Central

    Huang, Zhichao; Zhao, Xiaokun; Zhang, Lei; Zhong, Zhaohui; Xu, Ran; Zhang, Lianping

    2013-01-01

    Purpose To compare the efficacy of extracorporeal shock wave lithotripsy in managing residual stones after ureterolithotripsy and mini-percutaneous nephrolithotomy. Materials and Methods A retrospective study was carried out of 71 patients with proximal urinary tract stones (greater than 10 mm) who underwent ureterolithotripsy or mini-percutaneous nephrolithotomy at a single institution from 2009 to 2011. The 71 patients were divided into two groups: group I (n = 37) comprised patients who underwent ureterolithotripsy, and group II (n = 34) comprised patients who underwent mini-percutaneous nephrolithotomy. Clinical characteristics, stone-free rates, stone demographics, and complications were evaluated. Results The overall stone-free rate was 90.1%. The stone-free rates in groups I and II were 97.3% and 82.4%, respectively. There was a statistically significant difference in the stone-free rates between groups I and II (P = 0.035). Neither serious intraoperative nor postoperative complications were observed. No significant difference in complications was observed between the two groups (P = 0.472). Conclusions The results of our study suggest that extracorporeal shock wave lithotripsy is an effective and safe auxiliary procedure for managing residual stones after primary endoscopic surgery. This procedure is associated with a satisfactory stone-free rate and a low complication rate, particularly for residual stones after ureteroscopic procedures. PMID:23785516

  10. Instrumentation: endoscopes and equipment.

    PubMed

    Gaab, Michael R

    2013-02-01

    The technology and instrumentation for neuroendoscopy are described: endoscopes (principles, designs, applications), light sources, instruments, accessories, holders, and navigation. Procedures for cleaning, sterilizing, and storing are included. The description is based on the author's own technical development and neuroendoscopic experience, published technology and devices, and publications on endoscopic surgery. The main work horses in neuroendoscopy are rigid glass rod endoscopes (Hopkins optics) due to the optical quality, which allows full high-definition video imaging, different angles of view, and autoclavability, which is especially important in neuroendoscopy due to the risk of Creutzfeldt-Jakob disease infection. Applications are endoscopy assistance to microsurgery, stand-alone endoscopy controlled approaches such as transnasal skull base, ventriculoscopy, and cystoscopy in the cranium. Rigid glass rod optics are also applicable in spinal endoscopy and peripheral nerve decompression using special tubes and cannulas. Rigid minifiberoptics with less resolution may be used in less complex procedures (ventriculoscopy, cystoscopy, endoscopy assistance with pen-designs) and have the advantages of smaller diameters and disposable designs. Flexible fiberoptics are usually used in combination with rigid scopes and can be steered, e.g. through the ventricles, in spinal procedures for indications including syringomyelia and multicystic hydrocephalus. Upcoming flexible chip endoscopes ("chip-in-the-tip") may replace flexible fiberoptics in the future, offering higher resolution and cold LED-illumination, and may provide for stereoscopic neuroendoscopy. Various instruments (mechanical, coagulation, laser guides, ultrasonic aspirators) and holders are available. Certified methods for cleaning and sterilization, with special requirements in neuroapplications, are important. Neuroendoscopic instrumentation is now an established technique in neurosurgical practice and

  11. [Endoscopic surgery].

    PubMed

    Rushfeldt, Christian; Pham, Khanh Do-Cong; Aabakken, Lars

    2016-05-01

    Endoscopic surgery of the stomach/gastrointestinal tract was developed in the 1990s in Japan as a minimally invasive method of removing early-stage tumours, using a gastro-/coloscope instead of open or laparoscopic surgery. Its advantages are obvious, in that the patient is spared more major surgery, the hospital saves on resources as well as admission to a ward, and society is spared the costs of days of sickness absence. Endoscopic submucosal dissection is considered the most difficult technique, but it allows for the accurate dissection of large tumours. In 1999, Japanese surgeon Takuji Gotoda and his team were the first to perform these types of dissections of early cancers in the rectum using a diathermic needle and a flexible scope.

  12. Massive Pulmonary Calculi Embolism: A Novel Complication of Pneumatic Lithotripsy

    PubMed Central

    Zhang, Lin; Zhou, Yiwu

    2015-01-01

    Abstract Pneumatic lithotripsy is a minimally invasive technique mainly for the treatment of urinary staghorn stones. Previous literatures have reported some therapeutic complications during or after this procedure, but calculi embolism has not been mentioned before. We report here a fatal case of calculi-induced pulmonary embolism in an adult woman who underwent pneumatic lithotripsy. An autopsy did not reveal any evidence of pulmonary embolism. However, light microscopy revealed noticeable presence of calculi in pulmonary arterioles and capillaries, as evidenced by environmental scanning electron microscope and energy dispersive X-ray analysis. The primary determinants of calculi embolism include intrarenal pressure, and volume and viscosity of the calculi fragments formation. Vascular intravasation of smashed calculi might increase pulmonary vascular resistance and hypoxemia and decrease cardiac output. This case report intends to provide information for clinicians to consider the probability of intraoperative calculi embolism during lithotripsies when patients develop typical symptoms of acute pulmonary embolism. PMID:26222867

  13. Does extracorporeal shock wave lithotripsy cause hearing impairment in children?

    PubMed

    Tuncer, Murat; Sahin, Cahit; Yazici, Ozgur; Kafkasli, Alper; Turk, Akif; Erdogan, Banu A; Faydaci, Gokhan; Sarica, Kemal

    2015-03-01

    We evaluated the possible effects of noise created by high energy shock waves on the hearing function of children treated with extracorporeal shock wave lithotripsy. A total of 65 children with normal hearing function were included in the study. Patients were divided into 3 groups, ie those becoming stone-free after 1 session of shock wave lithotripsy (group 1, 22 children), those requiring 3 sessions to achieve stone-free status (group 2, 21) and healthy children/controls (group 3, 22). Extracorporeal shock wave lithotripsy was applied with patients in the supine position with a 90-minute frequency and a total of 2,000 shock waves in each session (Compact Sigma, Dornier MedTech, Wessling, Germany). Second energy level was used with a maximum energy value of 58 joules per session in all patients. Hearing function and possible cochlear impairment were evaluated by transient evoked otoacoustic emissions test at 1.0, 1.4, 2.0, 2.8 and 4.0 kHz frequencies before the procedure, 2 hours later, and 1 month after completion of the first shock wave lithotripsy session in groups 1 and 2. In controls the same evaluation procedures were performed at the beginning of the study and 7 weeks later. Regarding transient evoked otoacoustic emissions data, in groups 1 and 2 there was no significant alteration in values obtained after shock wave lithotripsy compared to values obtained at the beginning of the study, similar to controls. A well planned shock wave lithotripsy procedure is a safe and effective treatment in children with urinary stones and causes no detectable harmful effect on hearing function. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  14. Efficacy of the lithotripsy in treating lower pole renal stones.

    PubMed

    Cui, Helen; Thomee, Eeke; Noble, Jeremy G; Reynard, John M; Turney, Benjamin W

    2013-06-01

    Use of extracorporeal lithotripsy is declining in North America and many European countries despite international guidelines advocating it as a first-line therapy. Traditionally, lithotripsy is thought to have poor efficacy at treating lower pole renal stones. We evaluated the success rates of lithotripsy for lower pole renal stones in our unit. 50 patients with lower pole kidney stones ≤15 mm treated between 3/5/11 and 19/4/12 were included in the study. Patients received lithotripsy on a fixed-site Storz Modulith SLX F2 lithotripter according to a standard protocol. Clinical success was defined as stone-free status or asymptomatic clinically insignificant residual fragments (CIRFs) ≤3 mm at radiological follow-up. The mean stone size was 7.8 mm. The majority of stones (66 %) were between 5 and 10 mm. 28 % of stones were between 10 and 15 mm. For solitary lower pole stones complete stone clearance was achieved in 63 %. Total stone clearance including those with CIRFs was achieved in 81 % of patients. As expected, for those with multiple lower pole stones the success rates were lower: complete clearance was observed in 39 % and combined clearance including those with CIRFs was 56 %. Overall, complete stone clearance was observed in 54 % of patients and clearance with CIRFs was achieved in 72 % of patients. Success rate could not be attributed to age, stone size or gender. Our outcome data for the treatment of lower pole renal stones (≤15 mm) compare favourably with the literature. With this level of stone clearance, a non-invasive, outpatient-based treatment like lithotripsy should remain the first-line treatment option for lower pole stones. Ureteroscopy must prove that it is significantly better either in terms of clinical outcome or patient satisfaction to justify replacing lithotripsy.

  15. Limitations of extracorporeal shock wave lithotripsy.

    PubMed

    Madaan, Sanjeev; Joyce, Adrian D

    2007-03-01

    Extracorporeal shock wave lithotripsy (ESWL) is the preferred modality for the treatment of renal and upper ureteric calculi. The present review focuses on the limitations of ESWL, where recent developments have tried to identify patients who are unlikely to succeed with ESWL and where improvements in shock wave delivery may increase successful stone fragmentation. Evaluation of patients prior to ESWL is especially important, and the use of imaging in the decision process, with the use of computed tomography attenuation values and skin-to-stone distance, can help improve our ability to identify suitable patients for shock wave treatment. Continued research into the methods of shock wave delivery techniques and lithotripter designs will help achieve better stone fragmentation rates with reduced side effects. The importance of traditional factors in predicting ESWL success, such as stone size, location, composition and renal anatomy, are well known. More recently, authors have created nomograms to predict stone-free outcome after ESWL. Others have used the information obtained from computed tomography to predict stone comminution. In addition, modifications in shock wave delivery by altering shock rate and voltage have been researched in an effort to improve shock wave efficacy.

  16. Innovations in shock wave lithotripsy technology

    NASA Astrophysics Data System (ADS)

    Zhong, Pei; Zhou, Yufeng; Zhu, Songlin; Cocks, Franklin; Preminger, Glenn

    2003-10-01

    Since its introduction in early 1980s, shock wave lithotripsy (SWL) has been used widely in clinic for the treatment of kidney and upper urinary stones. Although a variety of methods have been developed for shock wave generation, coupling, and focusing, the core of SWL technology has not changed significantly. In this talk, we will present a summary of our research efforts, aiming to provide innovations in SWL technology. Our strategy is to first better understand the mechanisms by which stone comminution and tissue injury are produced in SWL using various experimental and theoretical techniques. Based on this knowledge, we then developed novel techniques that can optimize the effect of cavitation in SWL via modification of the waveform profile, pressure distribution, and pulse sequence of lithotripter-generated shock waves. These new techniques were upgraded on a Dornier HM-3 lithotripter, the gold standard in SWL. Both in vitro phantom and in vivo animal experiments were carried out which demonstrated that the performance and safety of the upgraded HM-3 lithotripter is superior to the original HM-3 lithotripter. Finally, strategies to improve stone comminution efficiency while reducing tissue injury in SWL will be presented. [Work supported by NIH DK52985 and DK58266.

  17. Observation of cavitation during shock wave lithotripsy

    NASA Astrophysics Data System (ADS)

    Bailey, Michael R.; Crum, Lawrence A.; Pishchalnikov, Yuri A.; McAteer, James A.; Pishchalnikova, Irina V.; Evan, Andrew P.; Sapozhnikov, Oleg A.; Cleveland, Robin O.

    2005-04-01

    A system was built to detect cavitation in pig kidney during shock wave lithotripsy (SWL) with a Dornier HM3 lithotripter. Active detection, using echo on B-mode ultrasound, and passive cavitation detection (PCD), using coincident signals on confocal, orthogonal receivers, were equally sensitive and were used to interrogate the renal collecting system (urine) and the kidney parenchyma (tissue). Cavitation was detected in urine immediately upon SW administration in urine or urine plus X-ray contrast agent, but in tissue, cavitation required hundreds of SWs to initiate. Localization of cavitation was confirmed by fluoroscopy, sonography, and by thermally marking the kidney using the PCD receivers as high intensity focused ultrasound sources. Cavitation collapse times in tissue and native urine were about the same but less than in urine after injection of X-ray contrast agent. Cavitation, especially in the urine space, was observed to evolve from a sparse field to a dense field with strong acoustic collapse emissions to a very dense field that no longer produced detectable collapse. The finding that cavitation occurs in kidney tissue is a critical step toward determining the mechanisms of tissue injury in SWL. [Work sup ported by NIH (DK43881, DK55674, FIRCA), ONRIFO, CRDF and NSBRI SMS00203.

  18. Cloud cavitation effects in shockwave lithotripsy

    NASA Astrophysics Data System (ADS)

    Colonius, Tim; Tanguay, Michel

    2003-10-01

    Cavitation has already been identified as an important damage mechanism in the comminution of kidney stones in shockwave lithotripsy (SWL). However, the precise conditions that maximize the damage caused by the collapsing bubbles are still unknown. Numerical simulations are used to investigate shock propagation and the consequent growth and collapse of a bubble cloud in the focal region of a lithotripter. In the simulations, a continuum two-phase flow model for the ensemble-averaged macroscale is coupled to a Gilmore model for individual spherical bubble dynamics at the microscale. The simulations show agreement with experimental pressure measurements and high-speed photography of the bubble cloud. At void fractions commensurate with experiments, it is found that the collective collapse of the bubble cloud provides a significant increase to the energy available for comminution (beyond what a single bubble would produce). Relatively small increases in the pressure at the center of the cloud in advance of collapse (two orders of magnitude smaller than the initial shock) can more than double the energy of the collapsing bubble.

  19. Experience of curing serious obstruction of advanced-stage upper digestive tract tumor using laser under endoscope

    NASA Astrophysics Data System (ADS)

    Mu, Hai-Bin; Zhang, Man-Ling; Zhang, Xiao-Qiang; Zhang, Feng-Qiu; Kong, De-Jia; Tang, Li-Bin

    1998-11-01

    The patients who suffer from upper digestive tract tumor, such as cancer of esophagus, cancer of cardia, all have serious obstruction and fail to get nutrition and can not bear the strike of the radiotherapy and chemotherapy. In order to reduce the obstruction symptom and suffering of the patients and to prolong their life time, since 1989, our hospital used the laser to cure the upper digestive tract tumor 11 cases with serious obstruction and got remarkable curative effect.

  20. Endoscopic Removal of a Nitinol Mesh Stent from the Ureteropelvic Junction after 15 Years

    PubMed Central

    Smrkolj, Tomaž; Šalinović, Domagoj

    2015-01-01

    We report a rare case of a patient with a large stone encrusted on a nitinol mesh stent in the ureteropelvic junction. The stent was inserted in the year 2000 after failure of two pyeloplasty procedures performed due to symptomatic ureteropelvic junction stenosis. By combining minimally invasive urinary stone therapies—extracorporeal shock wave lithotripsy, semirigid ureterorenoscopy with laser lithotripsy, and percutaneous nephrolithotomy—it was possible to completely remove the encrusted stone and nitinol mesh stent that was implanted for 15 years, rendering the patient symptom and obstruction free. PMID:26697258

  1. Endoscopic Ultrasound-Guided Needle-Based Probe Confocal Laser Endomicroscopy (nCLE) of Intrapancreatic Ectopic Spleen

    PubMed Central

    Bastidas, Amanda B.; Holloman, David; Lankarani, Ali

    2016-01-01

    Accessory spleens and splenosis represent the congenital and acquired type of ectopic splenic tissue. Generally, they are asymptomatic entities posing as solid hypervascular masses at the splenic hilum or in other organs, such as the pancreas. Intrapancreatic ectopic spleen mimics pancreatic neoplasms on imaging studies, and due to the lack of radiological diagnostic criteria, patients undergo unnecessary distal pancreatectomy. We present the first case of intrapancreatic ectopic spleen in which the concomitant use of needle-based probe confocal laser endomicroscopy and fine-needle aspiration supported the final diagnosis. PMID:27144203

  2. Percutaneous endoscopic treatment for urinary stones in pediatric patients: where we are now

    PubMed Central

    Collura, Giuseppe; Innocenzi, Michele; De Dominicis, Mauro; Gerocarni Nappo, Simona; Capozza, Nicola

    2016-01-01

    Background Percutaneous nephrolithotomy (PCNL) has been adopted for pyelo-calyceal stones treatment in pediatric patients, starting from the 90’s. Very recently, miniaturization of endoscopic instruments allowed less invasive procedures with low complication rate. We reviewed our experience on upper tract stone treatment utilizing two different percutaneous accesses, focusing on the recent new miniaturized devices offered for pediatric renal stones. Methods Patients presenting upper tract urinary stones observed from January 2011 to December 2015 and treated by percutaneous renal access were prospectively evaluated: age, sex, metabolic issues, associated abnormalities, treatment modalities, hospital stay and complication rate were recorded in a specific database. Two different endourological percutaneous modalities were adopted, depending to the stone size and position. PCNL was performed through a direct calyceal puncture under ultrasonographic and fluoroscopic guidance and Amplatz access dilatation till 24 Fr. Ballistic energy was used for fragmentation. Micropercutaneous (Microperc) procedure was recently offered utilizing a 4.85 Fr metallic needle and Holmium:YAG laser lithotripsy under direct vision through a 0.9 mm high resolution optic flexible wire connected with a telescope. Results Thirty-eight percutaneous access to pyelo-calyceal renal stones were performed on a total of 108 children treated for upper tract stones, aged 4 to 18 years (mean age 7.5 years). The overall number of procedures was 144 (36 repeated procedures). Cystinuria was diagnosed in 5 patients. PCNL was adopted in 28 patients, Microperc was utilized in 8 patients. Hemoglobin dropdown was limited to 1.20±0.80 mg% in PCNL and was not significant in Microperc. No blood transfusion was needed. No significant complications were observed. Stone free rate or minimal not significant residuals were achieved in 82% of PCNL and in 87.5% of Microperc, after a single procedure. Conclusions

  3. Management of surgical margins after endoscopic laser surgery for early glottic cancers: a multicentric evaluation in French-speaking European countries.

    PubMed

    Fakhry, Nicolas; Vergez, Sébastien; Babin, Emmanuel; Baumstarck, Karine; Santini, Laure; Dessi, Patrick; Giovanni, Antoine

    2015-06-01

    The aim of this study was to evaluate the practices of ENT surgeons for the management of surgical margins after endoscopic laser surgery for early glottic cancers. A questionnaire was sent to different surgeons managing cancers of the larynx in France, Belgium and Switzerland. A descriptive and comparative analysis of practices across centers was performed. Sixty-nine surgeons completed the questionnaire (58 in France, 10 in Belgium and 1 in Switzerland). In case of very close or equivocal resection margins after definitive histological examination, 67 % of surgeons perform close follow-up, 28 % further treatment and 5 % had no opinion. Factors resulting in a significant change in the management of equivocal or very close margins were: the country of origin (p = 0.011), the specialty of the multidisciplinary team leader (p = 0.001), the fact that radiation equipment is located in the same center (p = 0.027) and the access to IMRT technique (p = 0.027). In case of positive resection margins, 80 % of surgeons perform further treatment, 15 % surveillance, and 5 % had no opinion. The only factor resulting in a significant change in the management of positive margins was the number of cancers of the larynx treated per year (p = 0.011). It is important to spare, on one hand equivocal or very close margins and on the other hand, positive margins. Postoperative management should be discussed depending on intraoperative findings, patient, practices of multidisciplinary team, and surgeon experience. This management remains non-consensual and writing a good practice guideline could be useful.

  4. Treatment of Renal Calculi with Extracorporeal Shock Wave Lithotripsy

    PubMed Central

    Eberwein, P. M.; Denstedt, J. D.

    1992-01-01

    In 12 years, extracorporeal shock wave lithotripsy has replaced other treatment techniques for most surgical calculi in the upper urinary tract. Worldwide clinical series have documented its efficacy. Technological advances and modifications have significantly expanded the clinical applications of this technique. Imagesp1673-aFigure 3 PMID:21221368

  5. Control of Acoustic Cavitation with Application to Lithotripsy.

    DTIC Science & Technology

    2007-11-02

    cavitation contributes to kidney stone comminution and tissue damage. An electrical spark at the near focus of an underwater ellipsoidal reflector was the...Control of acoustic cavitation (sound-induced bubble activity) is the subject of this dissertation. Application is to clinical lithotripsy where

  6. Treatment protocols to reduce renal injury during shock wave lithotripsy

    PubMed Central

    McAteer, James A.; Evan, Andrew P.; Williams, James C.; Lingeman, James E.

    2010-01-01

    Purpose of review Growing concern over the acute and long-term adverse effects associated with shock wave lithotripsy calls for treatment strategies to reduce renal injury and improve the efficiency of stone breakage in shock wave lithotripsy. Recent findings Experimental studies in the pig model show that lithotripter settings for power and shock wave rate and the sequence of shock wave delivery can be used to reduce trauma to the kidney. Step-wise power ramping as is often used to acclimate the patient to shock waves causes less tissue trauma when the initial dose is followed by a brief (3–4 min) pause in shock wave delivery. Slowing the firing rate of the lithotripter to 60 shock waves/min or slower is also effective in reducing renal injury and has the added benefit of improving stone breakage outcomes. Neither strategy to reduce renal injury – not power ramping with ‘pause-protection’ nor delivering shock waves at reduced shock wave rate – have been tested in clinical trials. Summary Technique in lithotripsy is critically important, and it is encouraging that simple, practical steps can be taken to improve the safety and efficacy of shock wave lithotripsy. PMID:19195131

  7. Audiovisual distraction reduces pain perception during shockwave lithotripsy.

    PubMed

    Marsdin, Emma; Noble, Jeremy G; Reynard, John M; Turney, Benjamin W

    2012-05-01

    Lithotripsy is an established method to fragment kidney stones that can be performed without general anesthesia in the outpatient setting. Discomfort and/or noise, however, may deter some patients. It has been demonstrated that audiovisual distraction (AV) can reduce sedoanalgesic requirements and improve patient satisfaction in nonurologic settings, but to our knowledge, this has not been investigated with lithotripsy. This randomized controlled trial was designed to test the hypothesis that AV distraction can reduce perceived pain during lithotripsy. All patients in the study received identical analgesia before a complete session of lithotripsy on a fixed-site Storz Modulith SLX F2 lithotripter. Patients were randomized to two groups: One group (n=61) received AV distraction via a wall-mounted 32″ (82 cm) television with wireless headphones; the other group (n=57) received no AV distraction. The mean intensity of treatment was comparable in both groups. Patients used a visual analogue scale (0-10) to record independent pain and distress scores and a nonverbal pain score was documented by the radiographer during the procedure (0-4). In the group that received AV distraction, all measures of pain perception were statistically lower. The patient-reported pain score was reduced from a mean of 6.1 to 2.4 (P<0.0001), and the distress score was reduced from a mean of 4.4 to 1.0 (P=0.0001). The mean nonverbal score recorded by the radiographer was reduced from 1.5 to 0.5 (<0.0001). AV distraction significantly lowered patients' reported pain and distress scores. This correlated with the nonverbal scores reported by the radiographer. We conclude that AV distraction is a simple method of improving acceptance of lithotripsy and optimizing treatment.

  8. [Stone Cone® in ureteroscopic ballistic lithotripsy of proximal ureteral stones].

    PubMed

    Arancio, M; Guglielmetti, S; Delsignore, A; Landi, A; Marchetti, C; Mina, A; Marcato, M; Martinengo, C

    2008-01-01

    Stone Cone® (Microvasive-Boston Scientific Corp, USA) is a device which prevents retrograde calculus migration during endoscopic ureterolithotripsy. We have studied the safety and efficacy of this device in endoscopic ureterolithotripsy with ballistic energy in proximal ureteral stones. MATERIALS AND METHODS. From 01/02/2006 to 01/02/2008 we carried out 36 ureterorenoscopies (URS) for proximal ureteral stones (average age: 46, range: 15-73). A ballistic energy was used for stones fragmentation. In 18 patients (Group A) we carried out URS with the aid of Stone Cone®, which was not used in the other 18 patients (Group B). Semirigid 8 Ch or 10 Ch Storz ureteroscope and ballistic lithotriptor Swiss Lithoclast Master EMS® were used. In cases of migration, edema, and ureteral damage, a ureteral stent was used. RESULTS. In Group B patients (URS performed without Stone Cone®) the migration of the whole stone, or of clinically significant fragments, occurred 8 times (45%). All of these patients underwent external shockwave lithotripsy (ESWL) at a center equipped with a lithotriptor. A ureteral stent was placed in 14 cases (78%). In Group A, the migration of a stone requiring ESWL treatment occurred only once (5%). The ureteral stent was placed 8 times (45%). We had no significant complications during the procedure. CONCLUSIONS. The Stone Cone® is a safe and easy-to-use device. The cost of this device can be balanced by the reduction of postoperative ESWL treatments for lithiasic fragments pushing up into the kidneys (p<0.01), and of ureteral stent applications at the end of the procedure (p<0.05).

  9. A meta-analysis of the efficacy of ureteroscopic lithotripsy and extracorporeal shock wave lithotripsy on ureteral calculi.

    PubMed

    Xu, Yahong; Lu, Yi; Li, Jian; Luo, Shunwen; Liu, Yang; Jia, Zhigang; Chen, Ping; Guo, Yu; Zhao, Qihua; Ma, Xiaoping; Jia, Shufang

    2014-05-01

    To re-evaluated the clinic efficacy of ureteroscopic lithotripsy (URS) and extracorporeal shock wave lithotripsy (ESWL) on ureteral calculi with Cochrane systematic reviews in this paper. We searched clinical randomized controlled trials and prospective controlled trials in databases such as Cochrane library, Medline, Springer, Elsevier Science Direct, PubMed. Pooled estimate of risk ratios (RRs), standard mean difference (SMD) with 95% confidence intervals (CIs) were used as measure of effect sizes. Summary effect estimates were also stratified by sample size, study design and study region. The overall effect sizes were derived using a random-effects model or fixed-effects model when appreciated, and meta-analysis were conducted with software RewMan 5.0. The meta-analysis suggested that there were significant differences of post-treatment stone free rate, repeat treatment rate, patients' satisfaction, incidence of postoperative complications, operation time and hospital stays between ESWL treatment cases and URS treatment cases. But in the sample sizes analysis, there were no significant differences of the post-treatment stone free rate and repeat treatment rate when the sample sizes were less than 100. Compared to the ureteroscopic lithotripsy treatment, extracorporeal shock wave lithotripsy treatment provided a significantly lower post-treatment stone free rate, but it also obviously brought out less postoperative complications, shorter operation time and hospital stays.

  10. Endoscopic simple prostatectomy

    PubMed Central

    Borkowski, Tomasz; Chłosta, Piotr; Dobruch, Jakub; Fiutowski, Marek; Jaskulski, Jarosław; Słojewski, Marcin; Szydełko, Tomasz; Szymański, Michał; Demkow, Tomasz

    2014-01-01

    Introduction Many options exist for the surgical treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH), including transurethral resection of the prostate (TURP), laser surgery, and open adenomectomy. Recently, endoscopic techniques have been used in the treatment of BPH. Material and methods We reviewed clinical studies in PubMed describing minimally invasive endoscopic procedures for the treatment of BPH. Results Laparoscopic adenomectomy (LA) and robotic–assisted simple prostatectomy (RASP) were introduced in the early 2000s. These operative techniques have been standardized and reproducible, with some individual modifications. Studies analyzing the outcomes of LA and RASP have reported significant improvements in urinary flow and decreases in patient International Prostate Symptom Score (IPSS). These minimally invasive approaches have resulted in a lower rate of complications, shorter hospital stays, smaller scars, faster recoveries, and an earlier return to work. Conclusions Minimally invasive techniques such as LA and RASP for the treatment BPH are safe, efficacious, and allow faster recovery. These procedures have a short learning curve and offer new options for the surgeon treating BPH. PMID:25667758

  11. Damage mechanisms in shock wave lithotripsy (SWL)

    NASA Astrophysics Data System (ADS)

    Lokhandwalla, Murtuza

    Shock wave lithotripsy is a 'non-invasive' therapy for treating kidney stones. Focused shock waves fragment stones to a size that can be passed naturally. There is, however, considerable tissue injury, and the mechanisms of stone fragmentation and tissue injury are not well understood. This work investigates potential tissue damage mechanisms, with an aim towards enhancing stone fragmentation and minimizing tissue damage. Lysis of red blood cells (RBC's) due to in vitro exposure to shock waves was investigated. Fluid flow-fields induced by a non-uniform shock wave, as well as radial expansion/implosion of a bubble was hypothesized to cause cell lysis. Both the above flow-fields constitute an unsteady extensional flow, exerting inertial as well as viscous forces on the RBC membrane. The resultant membrane tension and the membrane areal strain due to the above flow-fields were estimated. Both were found to exert a significantly higher inertial force (50--100 mN/m) than the critical membrane tension (10 mN/m). Bubble-induced flow-field was estimated to last for a longer duration (˜1 microsec) compared to the shock-induced flow (˜1 ns) and hence, was predicted to be lytically more effective, in typical in vitro experimental conditions. However, in vivo conditions severely constrain bubble growth, and cell lysis due to shock-induced shear could be dominant. Hemolysis due to shock-induced shear, in absence of cavitation, was experimentally investigated. The lithotripter-generated shock wave was refocused by a parabolic reflector. This refocused wave-field had a tighter focus (smaller beam-width and a higher amplitude) than the lithotripter wave-field. Cavitation was eliminated by applying overpressure to the fluid. Acoustic emissions due to bubble activity were monitored by a novel passive cavitation detector (HP-PCD). Aluminum foils were also used to differentiate cavitational from non-cavitational mode of damage. RBC's were exposed to the reflected wave-field from

  12. Advances in endoscopic imaging in ulcerative colitis.

    PubMed

    Tontini, Gian Eugenio; Pastorelli, Luca; Ishaq, Sauid; Neumann, Helmut

    2015-01-01

    Modern strategies for the treatment of ulcerative colitis require more accurate tools for gastrointestinal imaging to better assess mucosal disease activity and long-term prognostic clinical outcomes. Recent advances in gastrointestinal luminal endoscopy are radically changing the role of endoscopy in every-day clinical practice and research trials. Advanced endoscopic imaging techniques including high-definition endoscopes, optical magnification endoscopy, and various chromoendoscopy techniques have remarkably improved endoscopic assessment of ulcerative colitis. More recently, optical biopsy techniques with either endocytoscopy or confocal laser endomicroscopy have shown great potential in predicting several histological changes in real time during ongoing endoscopy. Here, we review current applications of advanced endoscopic imaging techniques in ulcerative colitis and present the most promising upcoming headways in this field.

  13. Biliary lithotripsy using pulsed laser: experimental and clinical data

    NASA Astrophysics Data System (ADS)

    Ponchon, Thierry; Barkun, Alan N.; Gagnon, Pierre; Lambert, Rene

    1990-06-01

    In vitro study: 53 calculi were fragmented (Technomed pulsolith, 6OmJ/pulse, 2Hz). Initial visible stone damage and disruption into at least 2 large pieces were rapidly achieved (means of 20 to 1 53 pulses respectively). The disintegration to fragments 5mm or less was obtained after a mean of 780 pulses and required for 26% of stones more than 10 mm to be achieved. Decreasing stone size, stone mass, and an increasing bilirubin with a decreasing cholesterol content correlated significantly with the more rapid achievement of satisfactory fragmentation.

  14. Endoscopic orientation correction.

    PubMed

    Höller, Kurt; Penne, Jochen; Schneider, Armin; Jahn, Jasper; Guttiérrez Boronat, Javier; Wittenberg, Thomas; Feussner, Hubertus; Hornegger, Joachim

    2009-01-01

    An open problem in endoscopic surgery (especially with flexible endoscopes) is the absence of a stable horizon in endoscopic images. With our "Endorientation" approach image rotation correction, even in non-rigid endoscopic surgery (particularly NOTES), can be realized with a tiny MEMS tri-axial inertial sensor placed on the tip of an endoscope. It measures the impact of gravity on each of the three orthogonal accelerometer axes. After an initial calibration and filtering of these three values the rotation angle is estimated directly. Achievable repetition rate is above the usual endoscopic video frame rate of 30 Hz; accuracy is about one degree. The image rotation is performed in real-time by digitally rotating the analog endoscopic video signal. Improvements and benefits have been evaluated in animal studies: Coordination of different instruments and estimation of tissue behavior regarding gravity related deformation and movement was rated to be much more intuitive with a stable horizon on endoscopic images.

  15. [Extracorporeal lithotripsy in Spain in the 20th. Century].

    PubMed

    Arrabal Martín, M

    2000-10-01

    In November of 1998, the Spanish Association of Urology decides to carry out a study on the lithotripsy in Spain, through the Group of Work in Lithiasis Urinary, with the objective of knowing the n(o) and distribution of Units and the real situation of the extracorporeal litotripsy for shock waves, in connection with other complementary methods or therapeutic alternatives. We remit to all the Units of Lithotripsy a record of collection of data: Characteristic of the unit, no. of sick, localization of the calculi, complications, evolution and personal comments. 63 units of lithotripsy have participated in the study, at the moment 3 of them don't work and 23 belong to the Public Sanitary System. The Spanish population belong to 39,848,000 inhabitants, distributed in 17 autonomous communities, there is a lithotripsy unit for each 660,000 Spaniards. 264,875 sick people have been treated, they present synchronous bilateral lithiasis, 18,276 (6.9%) and a new treatment for relapse of calculi has been carried out in 18,592 sick people. The treated calculi are located at renal level in 60% of the cases, ureteral, 39% and vesical, 1%. The expelled, deposited or not expelled lithiasis residue corresponds to 9%, 6.8% and 6% respectively, and to 21.8% in total. After the analysis of these data, it is observed with evidence that in Spain, each million of inhabitants generate 602 cases of lithiasis/year, susceptible of being treated with shock waves. The distribution of resources decreases the complementary expenses: displacements, derivation temporary urinary, prevention infection urinary, analgesic, etc.

  16. [Extracorporeal shockwave biliary lithotripsy. Physical basis and clinical application].

    PubMed

    Méndez-Sánchez, N; Uribe-Esquivel, M; Bosques, F; de la Mora, G; Sánchez, J M; Ponciano, G

    1990-01-01

    Extracorporeal shock waves lithotripsy is a new procedure discovered and applied in the present decade to treat urinary and biliary stones. Shock waves are acoustic waves similar to sonic waves which follow the acoustic laws and therefore the shock waves can be refracted or reflected depending on the medium interface. Due to the high water content, the human body can be crossed by shock waves which eventually may be focused on the target stone. There are several commercially available shock waves generators, i.e. the spark gap emisors which were the first ones, and the piezoceramic and electromagnetic emisors. To focus the shock waves on a biliary stone the machines are provided with fluoroscopic or ultrasound devices or with both in the most advanced machines. Using an electromagnetic emisor (Lithostar plus) our group has treated 78 patients with biliary stones without analgesia or anesthesia. Total stone fragmentation was achieved in 85% of the cases. In patients with cholesterol gallstones who undergo lithotripsy, an adjuvant treatment with oral cholesterol solvent is mandatory. Extracorporeal biliary lithotripsy is free of mortality, and the morbidity is less than 5%.

  17. Pulsed infrared laser ablation and clinical applications

    NASA Astrophysics Data System (ADS)

    Chan, Kin Foong

    Sufficient light energy deposited in tissue can result in ablation and excessive thermal and mechanical damage to adjacent tissues. The goals of this research are to investigate the mechanisms of pulsed infrared laser ablation of tissue, to optimize laser parameters for minimizing unnecessary damage to healthy tissue, and to explore the potential of using pulsed infrared lasers for clinical applications, especially laser lithotripsy. A dual-channel optical low coherence reflectometer was implemented to measure the expansion and collapse velocities of a Q-switched Ho:YAG (λ = 2.12 μm) laser-induced cavitation in water. Cavitation wall velocities up to 11 m/s were measured with this technique, and the results were in fair agreement with those calculated from fast-flash photographic images. The dependence of ablation threshold fluence on calculus absorption was examined. Preliminary results indicated that the product of optical absorption and ablation threshold fluence, which is the heat of ablation, remained constant for a given urinary calculus type and laser pulse duration. An extended study examined the influence of optical absorption on pulsed infrared laser ablation. An analytical photothermal ablation model was applied and compared to experimental ablation results using an infrared free-electron laser at selected wavelengths between 2.12 μm and 6.45 μm Results were in good agreement with the model, and the ablation depths of urinary calculi were highly dependent upon the calculus optical absorption as well as light attenuation within the intrapulse ablation plume. An efficient wavelength for ablation corresponded to the wavelength of the Er:YAG laser (λ = 2.94 μm) suggested this laser should be examined for laser lithotripsy. Schlieren flash photography, acoustic transient measurements with a piezoelectric polyvinylidene-fluoride needle-hydrophone, mass loss measurements, and chemical analyses were employed to study the ablation mechanisms of the free

  18. Evaluation of the learning curve for thulium laser enucleation of the prostate with the aid of a simulator tool but without tutoring: comparison of two surgeons with different levels of endoscopic experience.

    PubMed

    Saredi, Giovanni; Pirola, Giacomo Maria; Pacchetti, Andrea; Lovisolo, Jon Alexander; Borroni, Giacomo; Sembenini, Federico; Marconi, Alberto Mario

    2015-06-09

    The aim of this study was to determine the learning curve for thulium laser enucleation of the prostate (ThuLEP) for two surgeons with different levels of urological endoscopic experience. From June 2012 to August 2013, ThuLEP was performed on 100 patients in our institution. We present the results of a prospective evaluation during which we analyzed data related to the learning curves for two surgeons of different levels of experience. The prostatic adenoma volumes ranged from 30 to 130 mL (average 61.2 mL). Surgeons A and B performed 48 and 52 operations, respectively. Six months after surgery, all patients were evaluated with the International Prostate Symptom Score questionnaire, uroflowmetry, and prostate-specific antigen test. Introduced in 2010, ThuLEP consists of blunt enucleation of the prostatic apex and lobes using the sheath of the resectoscope. This maneuver allows clearer visualization of the enucleation plane and precise identification of the prostatic capsule. These conditions permit total resection of the prostatic adenoma and coagulation of small penetrating vessels, thereby reducing the laser emission time. Most of the complications in this series were encountered during morcellation, which in some cases was performed under poor vision because of venous bleeding due to surgical perforation of the capsule during enucleation. Based on this analysis, we concluded that it is feasible for laser-naive urologists with endoscopic experience to learn to perform ThuLEP without tutoring. Those statements still require further validation in larger multicentric study cohort by several surgeon. The main novelty during the learning process was the use of a simulator that faithfully reproduced all of the surgical steps in prostates of various shapes and volumes.

  19. Retrograde intrarenal surgery monotherapy versus shock wave lithotripsy for stones 10 to 20 mm in preschool children: a prospective, randomized study.

    PubMed

    Mokhless, Ibrahim A; Abdeldaeim, Hussein M; Saad, Ashraf; Zahran, Abdel Rahman

    2014-05-01

    We compared the outcome of retrograde intrarenal surgery monotherapy vs shock wave lithotripsy for stones 10 to 20 mm in preschool children. This prospective study included 60 children with a mean ± SD age of 2.4 ± 1.3 years. Patients were randomly divided into 2 groups. Group 1 underwent shock wave lithotripsy and group 2 underwent retrograde intrarenal surgery as monotherapy. Retrograde intrarenal surgery was started using a 7.5Fr semirigid ureteroscope (Storz®) and the holmium laser, and completed by the Flex X™2 flexible ureterorenoscope. A ureteral access sheath was not used and only hydrodilatation was performed. Patients were evaluated preoperatively by ultrasound and plain abdominopelvic x-ray. Followup was 3 months. The stone-free rate after a single session treatment was 70% and 86.6% in groups 1 and 2, respectively. Mean operative time was 27.9 ± 3.5 and 40 ± 7.8 minutes, mean fluoroscopy exposure time was 60 ± 42 and 50 ± 35 seconds, and mean hospital stay was 6 ± 2 and 12 ± 8 hours, respectively. No major complication occurred in either group and no child in either group received blood transfusion. Nine group 1 patients needed a second shock wave lithotripsy session, of whom 2 required a third session. At 3 months the overall stone-free rate was 93.3% and 96.6% in groups 1 and 2, respectively. Retrograde intrarenal surgery is an option for treating medium sized renal stones in preschool children with results comparable to those of shock wave lithotripsy and a safe short-term outcome. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  20. Clinical comparison of extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy in treating renal calculi.

    PubMed Central

    Mays, N.; Challah, S.; Patel, S.; Palfrey, E.; Creeser, R.; Vadera, P.; Burney, P.

    1988-01-01

    STUDY OBJECTIVE: To compare extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy for efficacy in treating renal calculi. DESIGN: Non-randomised multicentre cohort study with 3 month follow up and 13 month data collection period. SETTING: Lithotripter centre in London, tertiary referral hospital, and urological clinics in several secondary and tertiary care centres. PATIENTS: 933 of 1001 patients treated by lithotripsy at the lithotripter centre were compared with 195 treated by nephrolithotomy. Missing patients were due to incomplete collection of data. Age and sex distributions and characteristics of the stones were similar in the two treatment groups. Two patients died in the lithotripsy group. Three month follow up was achieved in about 84% of both groups (783/933 for lithotripsy; 163/195 for nephrolithotomy). INTERVENTIONS: The nephrolithotomy group had surgical nephrolithotomy alone. In the lithotripsy group 83% (774/933) had lithotripsy alone, 11% (103/933) had combined lithotripsy and nephrolithotomy, and 6% (56/933) had lithotripsy plus ureteroscopy. Single and combined lithotripter treatments were analysed as one group and compared with nephrolithotomy. END POINT: Presence of stones three months after treatment. MEASUREMENTS AND MAIN RESULTS: Presence of residual stones was assessed by plain radiography, ultrasonography, or intravenous urography. After adjustment for age and size and position of stone for patients with single stones the likelihood of being free of stones three months after treatment was significantly greater in the nephrolithotomy group than the lithotripsy group (odds ratio 6.6; 95% confidence interval 3.0 to 14.6) and the response was particularly pronounced with staghorn calculi (62% (8/13) v 15% (141/96) patients free of stones after nephrolithotomy and lithotripsy, respectively). OTHER FINDINGS: 19%(146/775) of patients who had had lithotripsy had to be readmitted within three months after treatment compared with 14

  1. Minimally invasive percutaneous cystostomy with ureteroscopic pneumatic lithotripsy for calculus in bladder diverticula

    PubMed Central

    GU, SI-PING; YOU, ZHI-YUAN; HUANG, YUNTENG; LU, YI-JIN; HE, CAOHUI; CAI, XIAO-DONG; ZHOU, XIAO-MING

    2013-01-01

    The aim of this study was to investigate the effectiveness of minimally invasive percutaneous cystostomy with ureteroscopic pneumatic lithotripsy for treating calculus in bladder diverticula. Percutaneous cystostomy with ureteroscopic pneumatic lithotripsy was performed on six elderly male patients with calculi in bladder diverticula, who could not be treated with transurethral ureteroscopic lithotripsy. The stones were successfully removed from all patients, with no complications such as bladder perforation, rupture, urethritis or cystitis. The surgery time was 15–60 min, with an average time of 32 min. Postoperative ultrasound or X-ray examination showed no stone residues and the bladder stoma healed well. No recurrent stones were detected in the follow-up of 3–24 months (average, 16 months). Minimally invasive percutaneous cystostomy with ureteroscopic pneumatic lithotripsy is a safe, efficient and easy treatment for calculus in bladder diverticula. This method provides a new clinical approach for lithotripsy and we suggest that it is worthy of wider use. PMID:23837044

  2. Orbital endoscopic surgery.

    PubMed

    Prabhakaran, Venkatesh C; Selva, Dinesh

    2008-01-01

    Minimally invasive "keyhole" surgery performed using endoscopic visualization is increasing in popularity and is being used by almost all surgical subspecialties. Within ophthalmology, however, endoscopic surgery is not commonly performed and there is little literature on the use of the endoscope in orbital surgery. Transorbital use of the endoscope can greatly aid in visualizing orbital roof lesions and minimizing the need for bone removal. The endoscope is also useful during decompression procedures and as a teaching aid to train orbital surgeons. In this article, we review the history of endoscopic orbital surgery and provide an overview of the technique and describe situations where the endoscope can act as a useful adjunct to orbital surgery.

  3. Percutaneous papillary large balloon dilation during percutaneous cholangioscopic lithotripsy for the treatment of large bile-duct stones: a feasibility study.

    PubMed

    Han, Jee Young; Jeong, Seok; Lee, Don Haeng

    2015-03-01

    When access to a major duodenal papilla or endoscopic retrograde cholangiopancreatography has failed, percutaneous transhepatic cholangioscopic lithotripsy (PTCS-L) may be useful for removing common bile duct (CBD) stones. However, the feasibility and usefulness of percutaneous transhepatic papillary large-balloon dilation (PPLBD) during PTCS-L for the removal of large CBD stones has not been established. We aimed to determine the safety and efficacy of PPLBD for the treatment of large CBD stones. Eleven patients with large CBD stones in whom the access to the major papilla or bile duct had failed were enrolled prospectively. Papillary dilation was performed using a large (12-20 mm) dilation balloon catheter via the percutaneous transhepatic route. Post-procedure adverse events and efficacy of the stone retrieval were measured. The initial success rate of PPLBD was 100%. No patient required a basket to remove a stone after PPLBD. Electrohydraulic lithotripsy was required in 2 (18.2%) patients. The median time to complete stone removal after PPLBD was 17.8 min and no adverse events occurred after PPLBD. Asymptomatic hyperamylasemia was not encountered in any patients. This study indicates that PPLBD is safe and effective for removal of large CBD stones.

  4. Lasers.

    ERIC Educational Resources Information Center

    Schewe, Phillip F.

    1981-01-01

    Examines the nature of laser light. Topics include: (1) production and characteristics of laser light; (2) nine types of lasers; (3) five laser techniques including holography; (4) laser spectroscopy; and (5) laser fusion and other applications. (SK)

  5. Lasers.

    ERIC Educational Resources Information Center

    Schewe, Phillip F.

    1981-01-01

    Examines the nature of laser light. Topics include: (1) production and characteristics of laser light; (2) nine types of lasers; (3) five laser techniques including holography; (4) laser spectroscopy; and (5) laser fusion and other applications. (SK)

  6. New era of Endoscopic Approach for Sialolithiasis: Sialendoscopy

    PubMed Central

    Al-Abri, Rashid; Marchal, Francis

    2010-01-01

    Sialendoscopy is one of the innovations introduced in the last few years in the field of otolaryngology, head and neck surgery. Sialolithiasis and sialadenitis are two of the most frequently presenting disorders of the salivary glands. The diagnosis is most frequently confirmed by radiology and the treatment of sialolithiasis ranges from the use of surgery, intra-oral extraction or external lithotripsy, to the more frequent external excision of the gland. Sialendoscopy uses minimal invasive surgical techniques which allows for optical exploration of the salivary ductal system and extraction of the stones by a basket under endoscopic view. Sialendoscopy incorporates diagnostic with therapeutic procedures, as dictated by the clinical findings. This technique can be performed in most cases as an ambulatory, outpatient procedure under local anaesthesia. PMID:21509260

  7. New era of Endoscopic Approach for Sialolithiasis: Sialendoscopy.

    PubMed

    Al-Abri, Rashid; Marchal, Francis

    2010-12-01

    Sialendoscopy is one of the innovations introduced in the last few years in the field of otolaryngology, head and neck surgery. Sialolithiasis and sialadenitis are two of the most frequently presenting disorders of the salivary glands. The diagnosis is most frequently confirmed by radiology and the treatment of sialolithiasis ranges from the use of surgery, intra-oral extraction or external lithotripsy, to the more frequent external excision of the gland. Sialendoscopy uses minimal invasive surgical techniques which allows for optical exploration of the salivary ductal system and extraction of the stones by a basket under endoscopic view. Sialendoscopy incorporates diagnostic with therapeutic procedures, as dictated by the clinical findings. This technique can be performed in most cases as an ambulatory, outpatient procedure under local anaesthesia.

  8. Lasers in the management of calcified urinary tract stents

    NASA Astrophysics Data System (ADS)

    Nseyo, Unyime O.; Tunuguntla, Hari S. G. R.; Crone, Michael

    2003-06-01

    Indwelling double J ureteral stents are used for internal urinary diversion for ureteral obstruction and post-surgical drainage of the upper urinary tract. Stent calcification is a serious complication especially in those with forgotten stents. In a retrospective review of 16 patients (10 male and 6 female) we found holmium laser to be highly effective in the management of calcified stents. Encrustations/calcifications were noted on the distal end of the sent in 6 patiens (37.5%), middle and distal portions in 2 patients (12.5%), along the entire length of the stent in 3 patients (18.75%), lower portion of the stent in 4 patients (25%) and at the upper and lower ends of the stent in one patient (6.25%). Cystolitholapaxy, retrograde ureteroscopy (URS) with holmium: YAG (yttrium-aluminum-garnet) laser intracorporeal lithotripsy, percutaneous nephrostolithotomy (PNL) and antegrade URS with holmium: YAG laser intracorporeal lithotripsy were effectively performed without intraoperative complications. Lithotripsy became necessary before stent removal in 11 patients (68.75%). Holmium laser lithotripsy was useful in managing 7 patients (43.75%), and shockwave lithotripsy (SWL) in 6 patients (37.5%). In two patients (12.5%) both holmium and SWL were used before the stent can be removed.

  9. Endoscopic facelift: two years' experience.

    PubMed

    Chajchir, A

    1997-01-01

    In the upcoming Twenty-first Century, we will find many surgical methods and devices that come to fulfill one of the main objectives of the aesthetic plastic surgery: to reduce scars, especially in facial surgery. Endoscopy is one of those methods. In my experience of the last two years, I have used this technique, sometimes combined with CO2 laser to partially remove glabellar muscles and the platysma fibers of the middle part of the neck. This work shows the results from 160 patients undergoing endoscopic forehead lift and neck contouring, using specially designed instruments. The results are highly significant and satisfactory.

  10. Endoscopic palliation of tracheobronchial malignancies.

    PubMed Central

    Hetzel, M R; Smith, S G

    1991-01-01

    The prognosis for tracheobronchial tumours remains poor. Most patients can be offered only palliation. When the main symptom is breathlessness or refractory haemoptysis from a large airway tumour endoscopic treatment may be very effective. Over the last decade most attention has focused on the neodymium YAG laser. This often produces dramatic effects but has some important limitations. In the last few years better techniques for stenting and intrabronchial radiotherapy (brachytherapy) have also been developed. This article discusses the range of techniques now available and aims to help clinicians decide which patients may benefit from referral to centres providing these techniques. Images PMID:1712516

  11. Noninvasive management of obstructing ureteral stones using electromagnetic extracorporeal shock wave lithotripsy.

    PubMed

    Sighinolfi, M C; Chiara, S M; Micali, S; Salvatore, M; De Stefani, S; Stefano, D S; Saredi, G; Mofferdin, A; Grande, M; Bianchi, G; Giampaolo, B

    2008-05-01

    Extracorporeal shock wave lithotripsy (ESWL) represents noninvasive management of urolithiasis. Since the first HM3 model, technological progress has improved the efficacy and safety of this treatment. The current study aimed to evaluate the role of ESWL as a first-line emergency therapy of renal colic due to ureteral stone with impaired renal function. This prospective study enrolled all the patients admitted from the emergency room with acute renal colic meeting the following criteria: serum creatinine level ranging from 1.5 to 2.5 mg/dl, hydronephrosis, ureteral stones 6 to 15 mm in size, body mass index less than 30, normal renal function at baseline, and no evidence of urinary tract infection. The patients were submitted to a single-session emergency treatment using Dornier Litothripter S. Follow-up assessment, performed at 24 and 72 h, included radiologic and ultrasound examinations with renal function serum assessment. The end points were a decrease in creatinine level and a stone-free condition. A total of 40 patients were eligible for the study. The mean creatinine level at admission was 1.93 +/- 0.26 mg/dl. After the treatment, renal function recovery occurred for 34 subjects (85%), with a significant global decrease in creatinine levels (p = 0.00). The global stone-free rate 72 h after SWL was 67.5% (27/40). The patients with residual fragments were managed using re-SWL (n = 7) and endoscopic technique (n = 6). Emergency SWL represents an effective tool in the treatment of ureteral stones with hydronephrosis and slight renal impairment. Although complete stone clearance after one treatment still remains a difficult target, the actual role of SWL in the management of acute obstruction is to obtain ureteral canalization and renal function recovery.

  12. Extracorporeal shock wave lithotripsy for pancreatic and large common bile duct stones

    PubMed Central

    Tandan, Manu; Reddy, D Nageshwar

    2011-01-01

    Extraction of large pancreatic and common bile duct (CBD) calculi has always challenged the therapeutic endoscopist. Extracorporeal shockwave lithotripsy (ESWL) is an excellent tool for patients with large pancreatic and CBD calculi that are not amenable to routine endotherapy. Pancreatic calculi in the head and body are targeted by ESWL, with an aim to fragment them to < 3 mm diameter so that they can be extracted by subsequent endoscopic retrograde cholangiopancreatography (ERCP). In our experience, complete clearance of the pancreatic duct was achieved in 76% and partial clearance in 17% of 1006 patients. Short-term pain relief with reduction in the number of analgesics ingested was seen in 84% of these patients. For large CBD calculi, a nasobiliary tube is placed to help target the calculi, as well as bathe the calculi in saline - a simple maneuver which helps to facilitate fragmentation. The aim is to fragment calculi to < 5 mm size and clear the same during ERCP. Complete clearance of the CBD was achieved in 84.4% of and partial clearance in 12.3% of 283 patients. More than 90% of the patients with pancreatic and biliary calculi needed three or fewer sessions of ESWL with 5000 shocks being delivered at each session. The use of epidural anesthesia helped in reducing patient movement. This, together with the better focus achieved with newer third-generation lithotripters, prevents collateral tissue damage and minimizes the complications. Complications in our experience with nearly 1300 patients were minimal, and no extension of hospital stay was required. Similar rates of clearance of pancreatic and biliary calculi with minimal adverse effects have been reported from the centers where ESWL is performed regularly. In view of its high efficiency, non-invasive nature and low complication rates, ESWL can be offered as the first-line therapy for selected patients with large pancreatic and CBD calculi. PMID:22110261

  13. High-resolution imaging using endoscopic holography

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.

    1990-08-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help to their control. 1.

  14. Holographic high-resolution endoscopic image recording

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.

    1991-03-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help

  15. Interaction of Laser Induced Micro-shockwaves

    NASA Astrophysics Data System (ADS)

    Leela, Ch.; Bagchi, Suman; Tewari, Surya P.; Kiran, P. Prem

    Laser induced Shock Waves (LISWs) characterized by several optical methods provide Equation of State (EOS) for a variety of materials used in high-energy density physics experiments at Mbar pressures [1, 2]. Other applications include laser spark ignition for fuel-air mixtures, internal combustion engines, pulse detonation engines, laser shock peening [3], surface cleaning [4] and biological applications (SW lithotripsy) [5] to name a few.

  16. Clinical factors associated with postoperative hydronephrosis after ureteroscopic lithotripsy

    PubMed Central

    Kim, Sun Woo; Ahn, Ji Hoon; Yim, Sang Un; Cho, Yang Hyun; Shin, Bo Sung; Chung, Ho Seok; Yu, Ho Song; Oh, Kyung Jin; Kim, Sun-Ouck; Jung, Seung Il; Kang, Taek Won; Kwon, Dong Deuk; Park, Kwangsung

    2016-01-01

    Purpose This study aimed to determine the predictors of ipsilateral hydronephrosis after ureteroscopic lithotripsy for ureteral calculi. Materials and Methods From January 2010 to December 2014, a total of 204 patients with ureteral calculi who underwent ureteroscopic lithotripsy were reviewed. Patients with lack of clinical data, presence of ureteral rupture, and who underwent simultaneous percutaneous nephrolithotomy (PNL) were excluded. Postoperative hydronephrosis was determined via computed tomographic scan or renal ultrasonography, at 6 months after ureteroscopic lithotripsy. Multivariable analysis was performed to determine clinical factors associated with ipsilateral hydronephrosis. Results A total of 137 patients were enrolled in this study. The mean age of the patients was 58.8±14.2 years and the mean stone size was 10.0±4.6 mm. The stone-free rate was 85.4%. Overall, 44 of the 137 patients (32.1%) had postoperative hydronephrosis. Significant differences between the hydronephrosis and nonhydronephrosis groups were noted in terms of stone location, preoperative hydronephrosis, impacted stone, operation time, and ureteral stent duration (all, p<0.05). On multivariable analysis, increasing preoperative diameter of the hydronephrotic kidney (adjusted odds ratio [OR], 1.21; 95% confidence interval [CI], 1.12–1.31; p=0.001) and impacted stone (adjusted OR, 3.01; 95% CI, 1.15–7.61; p=0.031) independently predicted the occurrence of postoperative hydronpehrosis. Conclusions Large preoperative diameter of the hydronephrotic kidney and presence of impacted stones were associated with hydronephrosis after ureteroscopic stone removal. Therefore, patients with these predictive factors undergo more intensive imaging follow-up in order to prevent renal deterioration due to postoperative hydronephrosis. PMID:27617316

  17. Failure after shockwave lithotripsy: is outcome machine dependent?

    PubMed

    Argyropoulos, A N; Tolley, D A

    2009-10-01

    To investigate the issue of shockwave lithotripsy failure by studying the effect of machine crossover to the Technomed Sonolith Vision (TSV) lithotriptor in patients with previously unsuccessfully treated renal stones with the Dornier Compact Delta (DCD). Records were examined for the period between 1998 and 2006. Parameters analysed were: size, multiple/single stones, location, treatments/stone. Seventy-six patients fulfilled the inclusion criteria. Following lithotripsy with the TSV, the stone-free rate (SFR) at 3 months was 56.7%, and the success rate (stone-free and fragments < or = 4 mm, SR) 86.7%. Twenty-two patients had multiple stones and the majority of the stones were located in the lower calyx (59.2%). Mean size was 8.9 mm prior to treatment with the TSV machine (10.2 mm for DCD). Further analysis followed in a subgroup of 42 patients of the same stone size (+/-2 mm) before and after DCD sessions. Mean stone size was 7 mm. The SFR was 61.9% (62.9% vs. 40.9% for single and multiple stones), and the SR was 88.1%. No difference in SFR was found for single or multiple stones in any of the two groups. The term 'extracorporeal shockwave lithotripsy (ESWL)-resistant stones' needs to be re-examined, as treatment with a different lithotriptor was successful in a group of stones where another machine had failed. Lithotripters with different shock wave characteristics may result in difference in the results of ESWL. Future research in ESWL should focus on stone characteristics and development of machines with the ability to adapt to specific stone features.

  18. Extracorporeal shockwave lithotripsy for salivary calculi in pediatric patients.

    PubMed

    Ottaviani, F; Marchisio, P; Arisi, E; Capaccio, P

    2001-10-01

    Salivary gland lithiasis is uncommon in pediatric patients. Color Doppler ultrasonography (US) enables an accurate diagnosis of lithiasis to be made without exposure to the radiation of traditional imaging techniques. The development of minimally invasive techniques in the ENT field has made salivary lithotripsy a feasible alternative to traditional invasive surgery. The safety and efficacy of shock wave lithotripsy for salivary calculi were evaluated in pediatric patients. Seven children (5 males; age 4-15 years) with single calculi (mean diameter 4.4 mm) of the submandibular (n = 4) and parotid glands (n = 3) underwent extracorporeal electromagnetic shock wave lithotripsy (EESWL). In four cases the stone was intraductal (two submandibular and two parotideal) and in the remaining three cases it was intraparenchymal (two submandibular and one parotideal). In one case sedative anesthesia was performed. The mean number of therapeutic sessions was five. Patients were followed up clinically and with US for 6-72 months (mean 32 months). Complete disintegration of the calculi was achieved in five cases while in two cases a residual fragment < 2 mm in diameter was observed. None of the patients had recurrence of calculi in the treated gland. Mild self-limited adverse effects (pain, swelling of the gland, self-limiting bleeding from the duct, cutaneous petechiae) were observed in four cases. Our data suggest that EESWL is effective, safe and well tolerated; the minimal invasiveness of the technique suggests that EESWL should be used as the primary approach to salivary calculi in pediatric patients. The continuous US monitoring enables the efficacy of EESWL to be evaluated during both treatment and follow-up, with only slight discomfort for the pediatric patient.

  19. Tracking kidney stones with sound during shock wave lithotripsy

    NASA Astrophysics Data System (ADS)

    Kracht, Jonathan M.

    The prevalence of kidney stones has increased significantly over the past decades. One of the primary treatments for kidney stones is shock wave lithotripsy which focuses acoustic shock waves onto the stone in order to fragment it into pieces that are small enough to pass naturally. This typically requires a few thousand shock waves delivered at a rate of about 2 Hz. Although lithotripsy is the only non-invasive treatment option for kidney stories, both acute and chronic complications have been identified which could be reduced if fewer shock waves were used. One factor that could be used to reduce the number of shock waves is accounting for the motion of the stone which causes a portion of the delivered shock waves to miss the stone, yielding no therapeutic benefit. Therefore identifying when the stone is not in focus would allow tissue to be spared without affecting fragmentation. The goal of this thesis is to investigate acoustic methods to track the stone in real-time during lithotripsy in order to minimize poorly-targeted shock waves. A relatively small number of low frequency ultrasound transducers were used in pulse-echo mode and a novel optimization routine based on time-of-flight triangulation is used to determine stone location. It was shown that the accuracy of the localization may be estimated without knowing the true stone location. This method performed well in preliminary experiments but the inclusion of tissue-like aberrating layers reduced the accuracy of the localization. Therefore a hybrid imaging technique employing DORT (Decomposition of the Time Reversal Operator) and the MUSIC (Multiple Signal Classification) algorithm was developed. This method was able to localize kidney stories to within a few millimeters even in the presence of an aberrating layer. This would be sufficient accuracy for targeting lithotripter shock waves. The conclusion of this work is that tracking kidney stones with low frequency ultrasound should be effective clinically.

  20. Indomethacin as prophylaxis against ureteral colic following extracorporeal shock wave lithotripsy.

    PubMed

    Cole, R S; Palfrey, E L; Smith, S E; Shuttleworth, K E

    1989-01-01

    Ureteral colic occurs in 24 to 34 per cent of all patients following extracorporeal shock wave lithotripsy. Recent research has shown prostaglandin synthetase inhibitors to be effective in relieving the pain associated with ureteral colic. Our prospective, controlled, double-blind, randomized study was designed to test the efficacy of indomethacin in the prophylactic treatment of pain after extracorporeal shock wave lithotripsy. Patients undergoing extracorporeal shock wave lithotripsy were randomized into 2 groups. Group 1 received 100 mg. indomethacin suppositories twice daily and group 2 received placebo suppositories. After extracorporeal shock wave lithotripsy 2 analgesics were available to the patients: oral co-dydramol or intramuscular pethidine was offered in the normal manner by the nursing staff. The pre-extracorporeal shock wave lithotripsy x-ray was used to make a quantitative estimate of the total stone burden in each patient. The post-extracorporeal shock wave lithotripsy analgesic requirement was used to compare the 2 groups. Of 112 patients recruited to the study 55 received indomethacin and 57 received placebo. The request for analgesia in the 2 groups was not different (28 of 55 and 33 of 57, respectively). However, in the indomethacin group only 6 patients required pethidine (10 doses), compared to 18 (41 doses) in the placebo group. This difference is statistically significant (p less than 0.01). There was no difference between the 2 groups in the occurrence of ureteral steinstrasse. Indomethacin has been shown to be effective in the prophylactic treatment of ureteral colic after lithotripsy.

  1. [Extracorporeal shock-wave lithotripsy in horseshoe kidney].

    PubMed

    Blasco Casares, F J; Ibarz Servio, L; Ramón Dalmau, M; Ruiz Marcellán, F J

    1994-05-01

    Presentation of our experience in the use of extracorporeal shock wave lithotripsy (ESWL) for the treatment of lithiasis that occurred in 34 renal units from 28 patients with horseshoe kidneys. All patients but one were placed in supine decubitus with the calculus positioned in F2. A total of 47 sessions were performed for 34 treatments apart from 3 ureteroscopies for ureteral voiding. The results of the follow-up is absence of lithiasis in 13 renal units, debris of less than 3 mm in six, non-removable debris in 13 cases and relapse in two.

  2. Successful extracorporeal shock wave lithotripsy for sibling pancreatic duct stones.

    PubMed

    Kitajima, Y; Ohiwa, T; Yamada, T; Sano, H; Ohara, H; Nakazawa, T; Ando, H; Hashimoto, T; Nakamura, S; Nomura, T; Joh, T; Yokoyama, Y; Itoh, M

    2001-01-01

    We present a case of 2 brothers with idiopathic chronic pancreatitis associated with pancreatic duct stones which could be successfully disintegrated by extracorporeal shock wave lithotripsy (ESWL). An obvious etiology for the pancreatolithiasis, like alcohol or biliary disease, was lacking and point mutations of the cationic trypsinogen gene exons 2 and 3 were not detected in the long arm of the 7th chromosome. However, a hereditary etiology could not be precluded since pancreatolithiasis occurred in the siblings. There has been no recurrence of pancreatic stones during 42 months of follow-up periods, for both. ESWL, the least invasive therapy, appeared applicable and effective for pancreatolithiasis in the present cases.

  3. Direct insertion of an ultra-slim upper endoscope for cholangioscopy in patients undergoing choledochoduodenostomy.

    PubMed

    Choi, Hyun Jong; Moon, Jong Ho; Lee, Yun Nah; Kim, Hyun Su; Ha, Ji Su; Lee, Tae Hoon; Cha, Sang-Woo; Cho, Young Deok; Park, Sang-Heum

    2015-11-01

    Direct peroral cholangioscopy (POC) using an ultra-slim upper endoscope is one modality of POC for intraductal endoscopic evaluation and treatment of the bile duct. Choledochoduodenostomy (CDS) is one modality of biliary bypass surgery that provides a new route to the bile duct. We carried out direct POC using an ultra-slim upper endoscope without the use of accessories in 10 patients (four sump syndromes, three bile duct strictures and three intrahepatic duct stones) previously undergoing surgical CDS. Direct POC was successful in all patients. The use of an intraductal balloon catheter was required in one patient for advancement of the endoscope into the bile duct. Distal bile ducts with sump syndromes were cleared using baskets and water irrigation under direct POC. Cholangiocarcinoma was diagnosed in one patient with hilar bile duct stricture after cholangioscopic evaluation and a targeting forceps biopsy under direct POC. Intrahepatic duct stones were successfully extracted after intraductal fragmentation under direct POC. Oozing bleeding occurred during intraductal lithotripsy but stopped spontaneously. Direct POC using an ultra-slim upper endoscope without the assistance of accessories can easily be carried out in patients undergoing CDS. © 2015 The Authors. Digestive Endoscopy © 2015 Japan Gastroenterological Endoscopy Society.

  4. Laser applications in surgery.

    PubMed

    Azadgoli, Beina; Baker, Regina Y

    2016-12-01

    In modern medicine, lasers are increasingly utilized for treatment of a variety of pathologies as interest in less invasive treatment modalities intensifies. The physics behind lasers allows the same basic principles to be applied to a multitude of tissue types using slight modifications of the system. Multiple laser systems have been studied within each field of medicine. The term "laser" was combined with "surgery," "ablation," "lithotripsy," "cancer treatment," "tumor ablation," "dermatology," "skin rejuvenation," "lipolysis," "cardiology," "atrial fibrillation (AF)," and "epilepsy" during separate searches in the PubMed database. Original articles that studied the application of laser energy for these conditions were reviewed and included. A review of laser therapy is presented. Laser energy can be safely and effectively used for lithotripsy, for the treatment of various types of cancer, for a multitude of cosmetic and reconstructive procedures, and for the ablation of abnormal conductive pathways. For each of these conditions, management with lasers is comparable to, and potentially superior to, management with more traditional methods.

  5. Development of 3D holographic endoscope

    NASA Astrophysics Data System (ADS)

    Özcan, Meriç; Önal Tayyar, Duygu

    2016-03-01

    Here we present the development of a 3D holographic endoscope with an interferometer built around a commercial rigid endoscope. We consider recording the holograms with coherent and incoherent light separately without compromising the white light imaging capacity of the endoscope. In coherent light based recording, reference wave required for the hologram is obtained in two different ways. First, as in the classical holography, splitting the laser beam before the object illumination, and secondly creating the reference beam from the object beam itself. This second method does not require path-length matching between the object wave and the reference wave, and it allows the usage of short coherence length light sources. For incoherent light based holographic recordings various interferometric configurations are considered. Experimental results on both illumination conditions are presented.

  6. In vitro comparison of shock wave lithotripsy machines

    NASA Astrophysics Data System (ADS)

    Teichman, Joel M.; Cecconi, Patricia P.; Pearle, Margaret S.; Clayman, Ralph V.

    2005-04-01

    We tested the hypothesis that shock wave lithotripsy machines vary in the ability to fragment stones to small size. Calcium oxalate monohydrate, calcium phosphate, cystine and struvite calculi were fragmented in vitro with the Dornier HM3, Storz Modulith SLX, Siemens Lithostar C, Medstone STS-T, HealthTronics LithoTron 160, Dornier Doli S and Medispec Econolith lithotriptors. Stones were given 2000 shocks or the FDA limit. Post-lithotripsy fragment size was compared. Struvite calculi were completely fragmented by all devices. The mean incidence of calcium phosphate dihydrate, calcium oxalate monohydrate, and cystine stones rendered into fragments greater than 2 mm was 0% for the HM3, Modulith SLX and Lithostar C, 10% for the STS-T, 3% for the LithoTron 160, 29% for the Doli and 18% for the Econolith (p=0.04); 0% for the HM3, Modulith SLX, Lithostar C, STS-T and LithoTron 160, 4% for the Doli and 9% for the Econolith (p=0.15); 1% for the HM3, 0% for the Modulith SLX, 1% for the Lithostar C, 10% for the STS-T, 14% for the LithoTron 160, 3% for the Doli and 9% for the Econolith (p=0.44), respectively. Shock wave lithotriptors vary in fragmentation ability.

  7. In vivo pressure measurements of lithotripsy shock waves in pigs.

    PubMed

    Cleveland, R O; Lifshitz, D A; Connors, B A; Evan, A P; Willis, L R; Crum, L A

    1998-02-01

    Stone comminution and tissue damage in lithotripsy are sensitive to the acoustic field within the kidney, yet knowledge of shock waves in vivo is limited. We have made measurements of lithotripsy shock waves inside pigs with small hydrophones constructed of a 25-microm PVDF membrane stretched over a 21-mm diameter ring. A thin layer of silicone rubber was used to isolate the membrane electrically from pig fluid. A hydrophone was positioned around the pig kidney following a flank incision. Hydrophones were placed on either the anterior (shock wave entrance) or the posterior (shock wave exit) surface of the left kidney. Fluoroscopic imaging was used to orient the hydrophone perpendicular to the shock wave. For each pig, the voltage settings (12-24 kV) and the position of the shock wave focus within the kidney were varied. Waveforms measured within the pig had a shape very similar to those measured in water, but the peak pressure was about 70% of that in water. The focal region in vivo was 82 mm x 20 mm, larger than that measured in vitro (57 mm x 12 mm). It appeared that a combination of nonlinear effects and inhomogeneities in the tissue broadened the focus of the lithotripter. The shock rise time was on the order of 100 ns, substantially more than the rise time measured in water, and was attributed to higher absorption in tissue.

  8. Brushite Stone Disease as a Consequence of Lithotripsy?

    PubMed Central

    Krambeck, Amy E.; Handa, Shelly E.; Evan, Andrew P.; Lingeman, James E.

    2011-01-01

    The incidence of calcium phosphate (CaP) stone disease has increased over the last three decades; specifically, brushite stones are diagnosed and treated more frequently than in previous years. Brushite is a unique form of CaP, which in certain patients can form into large symptomatic stones. Treatment of brushite stones can be difficult since the stones are resistant to shock wave and ultrasonic lithotripsy, and often require ballistic fragmentation. Patients suffering from brushite stone disease are less likely to be rendered stone-free after surgical intervention and often experience stone recurrence despite maximal medical intervention. Studies have demonstrated an association between brushite stone disease and shock wave lithotripsy (SWL) treatment. Some have theorized that many brushite stone formers started as routine calcium oxalate (CaOx) stone formers who sustained an injury to the nephron (such as SWL). The injury to the nephron leads to failure of urine acidification and eventual brushite stone formation. We explore the association between brushite stone disease and iatrogenic induced transformation of CaOx stone disease to brushite by reviewing the current literature. PMID:20623223

  9. Ultrahigh-resolution endoscopic optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Chen, Yu; Herz, Paul R.; Hsiung, Pei-Lin; Aguirre, Aaron D.; Mashimo, Hiroshi; Desai, Saleem; Pedrosa, Macos; Koski, Amanda; Schmitt, Joseph M.; Fujimoto, James G.

    2005-01-01

    Early detection of gastrointestinal cancer is essential for the patient treatment and medical care. Endoscopically guided biopsy is currently the gold standard for the diagnosis of early esophageal cancer, but can suffer from high false negative rates due to sampling errors. Optical coherence tomography (OCT) is an emerging medical imaging technology which can generate high resolution, cross-sectional images of tissue in situ and in real time, without the removal of tissue specimen. Although endoscopic OCT has been used successfully to identify certain pathologies in the gastrointestinal tract, the resolution of current endoscopic OCT systems has been limited to 10 - 15 m for clinical procedures. In this study, in vivo imaging of the gastrointestinal tract is demonstrated at a three-fold higher resolution (< 5 m), using a portable, broadband, Cr4+:Forsterite laser as the optical light source. Images acquired from the esophagus, gastro-esophageal junction and colon on animal model display tissue microstructures and architectural details at high resolution, and the features observed in the OCT images are well-matched with histology. The clinical feasibility study is conducted through delivering OCT imaging catheter using standard endoscope. OCT images of normal esophagus, Barrett's esophagus, and esophageal cancers are demonstrated with distinct features. The ability of high resolution endoscopic OCT to image tissue morphology at an unprecedented resolution in vivo would facilitate the development of OCT as a potential imaging modality for early detection of neoplastic changes.

  10. Extracorporeal shockwave lithotripsy, endourology and open surgery: the management and follow-up of 200 patients with urinary calculi.

    PubMed Central

    Webb, D. R.; McNicholas, T. A.; Whitfield, H. N.; Wickham, J. E.

    1985-01-01

    The management and follow up of 200 consecutive patients with renal and ureteric calculi are presented. The primary treatment of 185 (92.5%) was by extracorporeal shockwave lithotripsy (ESWL), of whom three (1.6)%) with large calculi underwent percutaneous nephrolithotripsy (PCNL) prior to ESWL as a planned combined procedure. Twelve (6%) were treated by PCNL or ureterorenoscopy (URS) as their definitive treatment and three (1.5%) by conventional open renal and ureteric surgery. The average in-patient stay was 3.8 days and most returned to normal activity within one day of discharge. Of the 185 patients 102 (55%) required no analgesia after treatment by ESWL, 29 (15.6%) required parenteral analgesia and the rest were comfortable with oral non-narcotic medication. Thirty (16%) required auxillary treatment by percutaneous nephrostomy (PCN), PCNL and URS following ESWL for obstructive complications from stone particles. Two required further ESWL and one PCNL at three months for large fragments. Overall, open surgery was required for only 1% of renal calculi and 13% of ureteric stones. These results are consistant with the extensive West German experience confirming that most urinary calculi are now best managed by ESWL and endoscopic techniques. Where these facilities are available open surgery should only be necessary for less than 5% of upper urinary tract stones. PMID:4073760

  11. Risk factors for formation of steinstrasse after extracorporeal shock wave lithotripsy for pediatric renal calculi: a multivariate analysis model.

    PubMed

    El-Assmy, Ahmed; El-Nahas, Ahmed R; Elsaadany, Mohammed M; El-Halwagy, Samer; Sheir, Khaled Z

    2015-04-01

    To define various stone, renal and therapy factors that could affect steinstrasse (SS) formation after extracorporeal shock wave lithotripsy (SWL) for pediatric kidney stones. Thus, SS could be anticipated and prophylactically avoided From January 1999 through December 2012, 317 children underwent SWL with Dornier Lithotripter S for the treatment of renal stones. Univariate and multivariate statistical analyses of patients, stones and therapy characteristics in relation to the incidence of SS were performed to detect the factors that had a significant impact on SS formation. The overall incidence of SS was 8.5%. The steinstrasse was in the pelvic ureter in 74.1% of the cases, lumbar ureter in 18.5% and iliac ureter in 7.4%. Steinstrasse incidence significantly correlated with stone size, site and age of child. Steinstrasse was more common with increasing stone length and stones located in renal pelvis or upper calyx with the age below 4 years. A statistical model was constructed to estimate the risk of steinstrasse formation accurately. The equation for logistic regression is Z = -4.758 + B for age + B for size stone X length in mm + B for stone site. The stone size, site and age are the most important risk factors responsible for SS formation in children. Our regression analysis model can help with prospective identification of children who will be at risk of SS formation. Those children at high risk of SS formation should be closely monitored or treated by endoscopic maneuvers from the start.

  12. Endoscopic papillary large balloon dilation for the management of recurrent difficult bile duct stones after previous endoscopic sphincterotomy.

    PubMed

    Yoon, Hyung Geun; Moon, Jong Ho; Choi, Hyun Jong; Kim, Dong Choon; Kang, Myung Soo; Lee, Tae Hoon; Cha, Sang-Woo; Cho, Young Deok; Park, Sang-Heum; Kim, Sun-Joo

    2014-03-01

    Endoscopic management of recurrent bile duct stones after endoscopic sphincterotomy (EST) is effective and safe. However, repeat EST for extension of a previous EST for recurrent bile duct stones may involve substantial risk. The aim of the present study was to evaluate the safety and efficacy of endoscopic papillary large balloon dilation (EPLBD) without repeat EST for recurrent difficult bile duct stones after previous EST. From January 2006 to October 2010, a total of 52 patients were enrolled; all had undergone EPLBD (balloon diameter: 12-20 mm) to remove recurrent difficult bile duct stones after previous EST. In all patients, stone removal had failed with conventional methods using a basket and/or balloon. The size of the balloon for EPLBD was selected to fit the diameter of the common bile duct or the largest stone. The median interval between initial EST and stone recurrence was 2.2 years (range 1-10). Median diameters of thelargest stone and balloon were 20.1 mm (range 12-40) and 14.7 mm (range 12-20), respectively. Complete stone removal was achieved in all patients (100%). The median number of endoscopic retrograde cholangiopancreatography sessions needed for complete stone removal was 1.6 (range 1-3). Additional lithotripsy was required in 16 patients (30.7%). No procedure-related complications were documented, with the exception of four cases of asymptomatic hyperamylasemia. The recurrence rate of CBD stones after bile duct clearance was 17.3% (9/52) during the follow-up period (mean 27.0 ± 14.1 months). EPLBD without repeat EST is effective and relatively safe for the extraction of recurrent difficult bile duct stones after previous EST. © 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.

  13. Efficacy of percutaneous treatment of biliary tract calculi using the holmium:YAG laser.

    PubMed

    Hazey, J W; McCreary, M; Guy, G; Melvin, W S

    2007-07-01

    Few Western studies have focused on percutaneous techniques using percutaneous transhepatic choledochoscopy (PTHC) and holmium:yttrium-aluminum-garnet (YAG) laser to ablate biliary calculi in patients unable or unwilling to undergo endoscopic or surgical removal of the calculi. The authors report the efficacy of the holmium:YAG laser in clearing complex biliary calculi using percutaneous access techniques. This study retrospectively reviewed 13 non-Asian patients with complex secondary biliary calculi treated percutaneously using holmium:YAG laser. Percutaneous access was accomplished via left, right, or bilateral hepatic ducts and upsized for passage of a 7-Fr video choledochoscope. Lithotripsy was performed under choledochoscopic vision using a holmium:YAG laser with 200- or 365-microm fibers generating 0.6 to 1.0 joules at 8 to 15 Hz. Patients underwent treatment until stone clearance was confirmed by PTHC. Downsizing and subsequent removal of percutaneous catheters completed the treatment course. Seven men and six women with an average age of 69 years underwent treatment. All the patients had their biliary tract stones cleared successfully. Of the 13 patients, 3 were treated solely as outpatients. The average length of percutaneous access was 108 days. At this writing, one patient still has a catheter in place. The average number of holmium:YAG laser treatments required for stone clearance was 1.6, with no patients requiring more than 3 treatments. Of the 13 patients, 8 underwent a single holmium:YAG laser treatment to clear their calculi. Prior unsuccessful attempts at endoscopic removal of the calculi had been experienced by 7 of the 13 patients. Five patients underwent percutaneous access and subsequent stone removal as their sole therapy for biliary stones. Five patients were cleared of their calculi after percutaneous laser ablation of large stones and percutaneous basket retrieval of the remaining stone fragments. There was one complication of pain

  14. Laser applications in surgery

    PubMed Central

    Azadgoli, Beina

    2016-01-01

    In modern medicine, lasers are increasingly utilized for treatment of a variety of pathologies as interest in less invasive treatment modalities intensifies. The physics behind lasers allows the same basic principles to be applied to a multitude of tissue types using slight modifications of the system. Multiple laser systems have been studied within each field of medicine. The term “laser” was combined with “surgery,” “ablation,” “lithotripsy,” “cancer treatment,” “tumor ablation,” “dermatology,” “skin rejuvenation,” “lipolysis,” “cardiology,” “atrial fibrillation (AF),” and “epilepsy” during separate searches in the PubMed database. Original articles that studied the application of laser energy for these conditions were reviewed and included. A review of laser therapy is presented. Laser energy can be safely and effectively used for lithotripsy, for the treatment of various types of cancer, for a multitude of cosmetic and reconstructive procedures, and for the ablation of abnormal conductive pathways. For each of these conditions, management with lasers is comparable to, and potentially superior to, management with more traditional methods. PMID:28090508

  15. Residual Cholesteatoma After Endoscope-guided Surgery in Children.

    PubMed

    James, Adrian L; Cushing, Sharon; Papsin, Blake C

    2016-02-01

    Endoscopes can facilitate surgery within tympanomastoid recesses that are not visible with the operating microscope. This study investigates whether use of endoscopes to guide dissection of cholesteatoma leads to lower rates of residual cholesteatoma than using the endoscope only for inspection after microscope-guided dissection. Comparative cohort study. Tertiary pediatric center. Two hundred thirty-five patients with acquired or congenital cholesteatoma in children <18 years having intact canal wall surgery and follow-up >12 months. Comparison of group (A) microscope surgery followed by endoscopic inspection, with group (B) endoscope-guided dissection. Residual cholesteatoma rates, controlling for site of initial cholesteatoma, detection by second-stage surgery, and length of follow-up. Analysis of all patients showed endoscopic dissection was associated with less residua in the middle ear (risk difference = 0.12; p = 0.026, Kaplan-Meier log rank analysis; number needed to treat = 9) but not at other sites. When restricting analysis to ears that were evaluated with second look surgery, no significant reduction in residual disease was found after endoscopic dissection at any site (e.g., retrotympanic residua: 12% Group A versus 7% Group B (NS, Fisher exact test). Endoscopic dissection allowed more permeatal surgery. No complications were attributable to endoscope use. Wound complications occurred in 4% of open cases. Endoscopes enhance surgical access to tympanomastoid recesses. In conjunction with the availability of the operating microscope, angled instruments, and KTP laser, endoscope-guided dissection provides a small incremental benefit for prevention of residual cholesteatoma, and facilitates a minimally invasive approach.

  16. Endoscopic management of chronic radiation proctitis

    PubMed Central

    Rustagi, Tarun; Mashimo, Hiroshi

    2011-01-01

    Chronic radiation proctopathy occurs in 5%-20% of patients following pelvic radiotherapy. Although many cases resolve spontaneously, some lead to chronic symptoms including diarrhea, tenesmus, urgency and persistent rectal bleeding with iron deficiency anemia requiring blood transfusions. Treatments for chronic radiation proctitis remain unsatisfactory and the basis of evidence for various therapies is generally insufficient. There are very few controlled or prospective trials, and comparisons between therapies are limited because of different evaluation methods. Medical treatments, including formalin, topical sucralfate, 5-amino salicylic acid enemas, and short chain fatty acids have been used with limited success. Surgical management is associated with high morbidity and mortality. Endoscopic therapy using modalities such as the heater probe, neodymium:yttrium-aluminium-garnet laser, potassium titanyl phosphate laser and bipolar electrocoagulation has been reported to be of some benefit, but with frequent complications. Argon plasma coagulation is touted to be the preferred endoscopic therapy due to its efficacy and safety profile. Newer methods of endoscopic ablation such as radiofrequency ablation and cryotherapy have been recently described which may afford broader areas of treatment per application, with lower rate of complications. This review will focus on endoscopic ablation therapies, including such newer modalities, for chronic radiation proctitis. PMID:22147960

  17. Electrohydraulic lithotripsy of gall stones--in vitro and animal studies.

    PubMed Central

    Harrison, J; Morris, D L; Haynes, J; Hitchcock, A; Womack, C; Wherry, D C

    1987-01-01

    Electrohydraulic lithotripsy of human gall stones was investigated in vitro in a bath of saline and in a saline perfused bile duct. The technique was effective--only two stones could not be shattered. Electrohydraulic lithotripsy power requirement correlated with mechanical strength of stones, but not with biochemical composition. A trend toward higher power requirement was recorded with larger stones and stones over 2 cm in diameter could not be fragmented. Safety studies indicated that electrohydraulic lithotripsy was safe, provided the probe tip was not in contact with the bile duct wall. In vivo studies did not show any late effects after 10 days. Electrohydraulic lithotripsy is likely to be useful in the management of biliary calculi. Images Figs 1(a)-1(b) PMID:3570031

  18. Predicting clinical efficacy of photoangiolytic and cutting/ablating lasers using the chick chorioallantoic membrane model: implications for endoscopic voice surgery.

    PubMed

    Burns, James A; Kobler, James B; Heaton, James T; Anderson, R Rox; Zeitels, Steven M

    2008-06-01

    The optimal balance between a laser's clinical efficacy and collateral thermal damage is the major determinant for selection of a particular laser in endolaryngeal surgery. The chick chorioallantoic membrane (CAM) simulates the microvasculature of the human vocal fold and is, therefore, useful for testing effects of laser settings, mode of delivery, active cooling, and wavelength. Such information is essential for optimizing the effectiveness of lasers in treating laryngeal pathology while preserving vocal function. The thermal and coagulative effects of four lasers (585 nm PDL, 532 nm KTP, 2.01ìm Thulium, 10.6ìm CO2) were quantified at selected (and clinically relevant) energy settings before and after tissue cooling using the CAM model. Measures included imaging real-time vascular reactions in the CAM model (i.e., vessel coagulation and/or rupture), and post-procedure histologic analysis of CAM tissue. In each experiment, laser energy was applied to the CAM in a controlled manner. Cooling was done using a dermatological cold-air device, and temperatures were measured with a thermistor. Lasers tested included the photoangiolytic pulsed-dye (PDL) and KTP, as well as the ablative/cutting CO2 and thulium lasers. The vessel rupture/coagulation and thermal effects of various energy-delivery parameters on the CAM, with and without cooling, were assessed. After removal of the CAM, specimens were stained as whole-mounts, photographed at 4X magnification, and evaluated by two independent, blinded surgeon reviewers. The efficacy of increased pulse-width (KTP laser) on treating larger vessels (>0.5 mm) and the effects of extravasated blood on photoangiolysis were also evaluated. Photoangiolytic lasers: Vessel coagulation/rupture rates showed that the PDL caused more frequent vessel rupture than the KTP laser. For both lasers, cooling the CAM by approximately 20 degrees C resulted in 30% - 60% reduction in the thermal-damage zone (P < .05). Cooling reduced the efficacy of

  19. Patient information leaflets for extracorporeal shock wave lithotripsy: questionnaire survey

    PubMed Central

    Askari, A; Shergill, I

    2012-01-01

    Objectives To compare the level of information provided in extracorporeal shock wave lithotripsy (ESWL) patient information leaflets in the London and East of England Deaneries Design All trusts in the London and East of England Deanery who offer an ESWL service were contacted and leaflets were compared Setting London and East of England Deanery Participants Alan Askari, Iqbal Shergill Main outcome measures Examination of key information that was communicated to ESWL patients via leaflets Results 12 trusts responded across the two deaneries. There was significant variation in the amount of information provided in the leaflets with some leaflets not containing an adequate level of instruction or information to patients Conclusions The authors propose that a national standardised information leaflet should be incorporated with the British Association of Urological Surgeons (BAUS) procedure specific information leaflet for ESWL procedures PMID:22666532

  20. Ultrasound guided lithotripsy of salivary calculi using an electromagnetic lithotriptor.

    PubMed

    Eggers, G; Chilla, R

    2005-12-01

    Sialolithiasis is a common disease of the major salivary glands. A supplement to the traditional therapies is extracorporeal shock wave lithotripsy of the calculus. This method has been adopted from the therapy of renal or bladder calculi. Patients with a solitary calculus of parotid or submandibular gland were treated with a specially designed lithotriptor. In a retrospective study the results of this therapy were analysed. The success rate was far better for parotid gland calculi than for submandibular calculi. We could not find better results than those published in literature with other devices. In our therapeutic concept, sialolithotripsy is the therapy of first choice for single parotid gland calculi. For submandibular gland calculus this method is advisable in selected cases only.

  1. [Extracorporeal shockwave lithotripsy in patients with coagulation disorders].

    PubMed

    Ruiz Marcellán, F J; Mauri Cunill, A; Cabré Fabré, P; Argentino Gancedo Rodríguez, V; Güell Oliva, J A; Ibarz Servio, L; Ramón Dalmau, M

    1992-03-01

    During treatment of renal lithiasis with extracorporeal shock wave lithotripsy (ESWL) hemorrhagic events, especially renal hematoma, may present. A coagulation study is warranted in order to institute hemotherapy for blood factor deficiencies. We reviewed the records of 4,000 patients that had undergone ESWL. Of these, 17 (12 males, 5 females) presented coagulation disorders. The bleeding diatheses were due to platelet deficiency in 6 cases, plasma defects in 5, platelet and plasma disorders in 2, and capillary wall defects in 5 cases. The underlying cause was hepatosplenic disease in 12 cases, iatrogenic in 1, connectivopathy and corticoids in 2, and capillary purpura of unknown cause in 2 cases. Due to this protocol, no patient presented hemorrhage or hematoma from shock wave-induced lesions. These results show that a complete coagulation study must be performed in order to institute the necessary measures in patients with disorders of hemostasis due to the high risk of hematoma repeatedly reported in the literature.

  2. Is extracorporeal shockwave lithotripsy suitable treatment for lower ureteric stones?

    PubMed

    Cole, R S; Shuttleworth, K E

    1988-12-01

    Forty patients with lower ureteric calculi for which intervention was considered desirable have been treated by in situ extracorporeal shockwave lithotripsy (ESWL) on the Dornier HM3 Lithotripter using a modified technique. Stone localisation was satisfactory in all patients. Adequate disintegration was achieved in 90% of patients following one treatment; 34 patients have been followed up for at least 3 months and 27 of these are stone-free (79%). Treatment failed in 4 patients and 2 of these had dense lower ureteric stone streets as a result of previous ESWL. The retreatment rate, post-treatment auxiliary procedure rate and complication rate were minimal. It was concluded that in situ ESWL is an effective and safe method for treating certain selected lower ureteric stones and should be considered as a feasible alternative to the more conventional methods of treatment.

  3. Endoscopic Management of Esthesioneuroblastoma.

    PubMed

    Roxbury, Christopher R; Ishii, Masaru; Gallia, Gary L; Reh, Douglas D

    2016-02-01

    Esthesioneuroblastoma is a rare malignant tumor of sinonasal origin. These tumors typically present with unilateral nasal obstruction and epistaxis, and diagnosis is confirmed on biopsy. Over the past 15 years, significant advances have been made in endoscopic technology and techniques that have made this tumor amenable to expanded endonasal resection. There is growing evidence supporting the feasibility of safe and effective resection of esthesioneuroblastoma via an expanded endonasal approach. This article outlines a technique for endoscopic resection of esthesioneuroblastoma and reviews the current literature on esthesioneuroblastoma with emphasis on outcomes after endoscopic resection of these malignant tumors.

  4. Pre-Emptive Tramadol Could Reduce Pain after Ureteroscopic Lithotripsy

    PubMed Central

    Denčić, Nataša; Jovičić, Jelena; Mirković, Jelena; Durutović, Otaš; Milenković-Petronić, Dragica; Lađević, Nebojša

    2014-01-01

    Purpose Optimal analgesia in ambulatory urology patients still remains a challenge. The aim of this study was to examine if the pre-emptive use of intravenous tramadol can reduce pain after ureteroscopic lithotripsy in patients diagnosed with unilateral ureteral stones. Materials and Methods This prospective pilot cohort study included 74 patients diagnosed with unilateral ureteral stones who underwent ureteroscopic lithotripsy under general anesthesia in the Urology Clinic at the Clinical Center of Serbia from March to June 2012. All patients were randomly allocated to two groups: one group (38 patients) received intravenous infusion of tramadol 100 mg in 500 mL 0.9%NaCl one hour before the procedure, while the other group (36 patients) received 500 mL 0.9%NaCl at the same time. Visual analogue scale (VAS) scores were recorded once prior to surgery and two times after the surgery (1 h and 6 h, respectively). The patients were prescribed additional postoperative analgesia (diclofenac 75 mg i.m.) when required. Pre-emptive effects of tramadol were assessed measuring pain scores, VAS1 and VAS2, intraoperative fentanyl consumption, and postoperative analgesic requirement. Results The average VAS1 score in the tramadol group was significantly lower than that in the non-tramadol group. The difference in average VAS2 score values between the two groups was not statistically significant; however, there were more patients who experienced severe pain in the non-tramadol group (p<0.01). The number of patients that required postoperative analgesia was not statistically different between the groups. Conclusion Pre-emptive tramadol did reduce early postoperative pain. The patients who received pre-emptive tramadol were less likely to experience severe post-operative pain. PMID:25048508

  5. Shock wave lithotripsy in patients with renal calculi.

    PubMed

    Tayib, Abdulmalik M; Mosli, Hisham A; Farsi, Hasan M; Atwa, Mahmoud A; Saada, Hisham A

    2008-08-01

    To demonstrate the efficacy of shock wave lithotripsy (SWL) in the primary treatment of 1647 patients with renal calculi using a Dornier Doli U/50 lithotripter. One thousand and six hundred forty-seven patients underwent SWL as day-cases at King Abdulaziz University Hospital in Jeddah, Saudi Arabia between October 2001 and July 2007, using intravenous sedation (Pethidine 1mg/kg and Midazolam 5-10mg) for analgesia in 85.5% of the patients. The treatment outcome of 2241 renal calculi was analyzed and stratified according to the size and the site of the stones. Recorded data included shock waves intensity, number of shocks, treatment time, analgesia, stone related factors such as size, site, number, nature, composition, and any related complications. The stones were grouped into 5 groups according to the largest stone size in the kidney. Patients were followed up for 6-18 months, mean of 13 months. Complete clearance of the stones occurred in 2154 kidneys (89.5%). At 3-months follow up. The overall re-treatment rate was 57.2% and for each group it was 132 (23.5%) for Group I, 254 (36.1%) for Gourp II, 473 (85.5%) for Group III, 278 (100%) for Group IV and 147 100% for Group V. Treatment failed in 87 patients with stone size of 20-29mm in 57 patients, and in 30 patients with stone size of 30-39mm. Fifty-six were solitary pelvic stones treated with ureteroscopy, while 31 were calyceal stones treated by other modalities such as percutaneousnephro-lithotomy. The most common complication was pyelonephritis with or without obstruction. Shock wave lithotripsy treatment was a successful primary management of renal stones of variable sizes in 89.5% of the treated kidneys.

  6. Is endoscopic papillary balloon dilatation really a risk factor for post-ERCP pancreatitis?

    PubMed Central

    Fujisawa, Toshio; Kagawa, Koichi; Hisatomi, Kantaro; Kubota, Kensuke; Nakajima, Atsushi; Matsuhashi, Nobuyuki

    2016-01-01

    Endoscopic papillary balloon dilatation (EPBD) is useful for decreasing early complications of endoscopic retrograde cholangio-pancreatography (ERCP), including bleeding, biliary infection, and perforation, but it is generally avoided in Western countries because of a relatively high reported incidence of post-ERCP pancreatitis (PEP). However, as the efficacy of endoscopic papillary large-balloon dilatation (EPLBD) becomes widely recognized, EPBD is attracting attention. Here we investigate whether EPBD is truly a risk factor for PEP, and seek safer and more effective EPBD procedures by reviewing past studies. We reviewed thirteen randomised control trials comparing EPBD and endoscopic sphincterotomy (EST) and ten studies comparing direct EPLBD and EST. Three randomized controlled trials of EPBD showed significantly higher incidence of PEP than EST, but no study of EPLBD did. Careful analysis of these studies suggested that longer and higher-pressure inflation of balloons might decrease PEP incidence. The paradoxical result that EPBD with small-calibre balloons increases PEP incidence while EPLBD does not may be due to insufficient papillary dilatation in the former. Insufficient dilatation could cause the high incidence of PEP through the use of mechanical lithotripsy and stress on the papilla at the time of stone removal. Sufficient dilation of the papilla may be useful in preventing PEP. PMID:27468185

  7. Endoscopic thoracic sympathectomy

    MedlinePlus

    Endoscopic thoracic sympathectomy (ETS) is surgery to treat sweating that is much heavier than normal. This condition ... hyperhidrosis . Usually the surgery is used to treat sweating in the palms or face. The sympathetic nerves ...

  8. Endoscopic Sinus Surgery

    MedlinePlus

    ... information in the popular media may not reflect reality. Although useful, balloon sinuplasty is not for everyone. In many cases standard endoscopic sinus surgery or medical therapy may be the best treatment. However, in some ...

  9. Endoscopic cubital tunnel release.

    PubMed

    Cobb, Tyson K

    2010-10-01

    A minimally invasive endoscopic approach has been successfully applied to surgical treatment of cubital tunnel syndrome. This procedure allows for smaller incisions with faster recovery time. This article details relevant surgical anatomy, indications, contraindications, surgical technique, complications, and postoperative management.

  10. Endoscopic thoracic sympathectomy.

    PubMed

    Moraites, Eleni; Vaughn, Olushola Akinshemoyin; Hill, Samantha

    2014-10-01

    Endoscopic thoracic sympathectomy is a surgical technique most commonly used in the treatment of severe palmar hyperhidrosis in selected patients. The procedure also has limited use in the treatment axillary and craniofacial hyperhidrosis. Endoscopic thoracic sympathectomy is associated with a high rate of the development of compensatory hyperhidrosis, which may affect patient satisfaction with the procedure and quality of life. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Endoscopic ultrasound hemostasis techniques.

    PubMed

    Artifon, Everson L A; Aparicio, Dayse P S; Otoch, Jose P; Carvalho, Paulo B; Marson, Fernando P; Fernandes, Kaie; Tchekmedyian, Asadur J

    2014-04-01

    Since its development, endoscopic ultrasound (EUS) has evolved from a simple diagnostic technique to an important therapeutic tool for interventional endoscopy. EUS analysis provides real-time imaging of most major thoracic and abdominal vessels, and the possibility to use needle puncture with a curved linear array echoendoscope as a vascular intervention. In this review, we describe the endoscopic ultrasound approach to vascular therapy outside of the gastrointestinal wall.

  12. Extracorporeal shock-wave lithotripsy: a comparative study of electrohydraulic and electromagnetic units.

    PubMed

    Matin, S F; Yost, A; Streem, S B

    2001-12-01

    We determined the results of shock wave lithotripsy with a newer electromagnetic lithotriptor and compared them with those in a contemporary series of cases managed by an electrohydraulic lithotriptor using identical treatment and followup criteria at a single center. Between 1995 and 1999, 356 patients (375 renal units, 483 upper urinary tract stones) meeting study inclusion criteria were treated with an MFL 5000 electrohydraulic shock wave lithotripsy unit (Dornier Medical Systems, Inc., Marietta, Georgia). From 1999 to 2000, 173 patients (175 renal units; 218 upper urinary tract stones) meeting identical study inclusion criteria were treated using an electromagnetic Modulith SLX shock wave lithotripsy unit (Karl Storz Lithotripsy, Atlanta, Georgia). In each group stone-free results were determined by plain abdominal x-ray and renal ultrasound 1 month after lithotripsy and efficiency quotients were developed. Baseline patient and stone characteristics were compared by the Wilcoxon rank sum and Fisher exact tests. All variables significant at p <0.05 were included in subsequent outcome analysis using multivariate logistic regression. Baseline characteristics were equivalent, including patient age, gender, stone number and location, although patients treated with the electrohydraulic unit had a significantly larger median stone burden (103 versus 71 mm.2, p = 0.015). Multivariate regression analysis demonstrated a higher stone-free rate in the electrohydraulic group (77% versus 67%, p = 0.01) but also a higher rate of total adjunctive measures (56% versus 47%, p = 0.04). Consequently the efficiency quotients were comparable for the electrohydraulic and electromagnetic lithotripsy units (0.45 and 0.42, respectively, p = 0.43). Electrohydraulic lithotripsy resulted in a higher stone-free rate at 1 month, although it was associated with a higher rate of auxiliary measures. Ultimately the efficiency quotients were equivalent, implying that these 2 contemporary energy

  13. Endoscopic treatment of tracheal stenosis.

    PubMed

    Freitag, Lutz; Darwiche, Kaid

    2014-02-01

    For all cases of tracheal obstructions surgery should be considered first. Interventional endoscopic procedures can provide immediate relief. Intraluminally growing tumors can be resected with laser, argon-plasma coagulation, an electrosurgical knife or cryo-probe. Photodynamic therapy of smaller tracheal tumors can be curative. Narrowing from intramural tumor growth or wall destruction requires internal splinting with an airway stent. Scar strictures can be dilated with balloons but the biotrauma may stimulate new scarring. In benign strictures and malacias, tracheal stents should only be placed if all other methods are exhausted. Complications including stent migration, mucostasis, halitosis and granulation tissue development must be considered. Most important for a good outcome is a multidisciplinary approach. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Dual-channel spectrally encoded endoscopic probe.

    PubMed

    Engel, Guy; Genish, Hadar; Rosenbluh, Michael; Yelin, Dvir

    2012-08-01

    High quality imaging through sub-millimeter endoscopic probes provides clinicians with valuable diagnostics capabilities in hard to reach locations within the body. Spectrally encoded endoscopy (SEE) has been shown promising for such task; however, challenging probe fabrication and high speckle noise had prevented its testing in in vivo studies. Here we demonstrate a novel miniature SEE probe which incorporates some of the recent progress in spectrally encoded technology into a compact and robust endoscopic system. A high-quality miniature diffraction grating was fabricated using automated femtosecond laser cutting from a large bulk grating. Using one spectrally encoded channel for imaging and a separate channel for incoherent illumination, the new system has large depth of field, negligible back reflections and well controlled speckle noise which depends on the core diameter of the illumination fiber. Moreover, by using a larger imaging channel, higher groove density grating, shorter wavelength and broader spectrum, the new endoscopic system now allow significant improvements in almost all imaging parameter compared to previous systems, through an ultra-miniature endoscopic probe.

  15. Dual-channel spectrally encoded endoscopic probe

    PubMed Central

    Engel, Guy; Genish, Hadar; Rosenbluh, Michael; Yelin, Dvir

    2012-01-01

    High quality imaging through sub-millimeter endoscopic probes provides clinicians with valuable diagnostics capabilities in hard to reach locations within the body. Spectrally encoded endoscopy (SEE) has been shown promising for such task; however, challenging probe fabrication and high speckle noise had prevented its testing in in vivo studies. Here we demonstrate a novel miniature SEE probe which incorporates some of the recent progress in spectrally encoded technology into a compact and robust endoscopic system. A high-quality miniature diffraction grating was fabricated using automated femtosecond laser cutting from a large bulk grating. Using one spectrally encoded channel for imaging and a separate channel for incoherent illumination, the new system has large depth of field, negligible back reflections and well controlled speckle noise which depends on the core diameter of the illumination fiber. Moreover, by using a larger imaging channel, higher groove density grating, shorter wavelength and broader spectrum, the new endoscopic system now allow significant improvements in almost all imaging parameter compared to previous systems, through an ultra-miniature endoscopic probe. PMID:22876349

  16. Enhanced endoscopic detection of early colon cancer

    NASA Astrophysics Data System (ADS)

    Balachandar, Gowra; Trowers, Eugene A.

    1999-06-01

    Enhanced endoscopic detection of small flat adenomas is becoming increasingly important as they have a reported 14 percent incidence of dysplasia when compared with 5% incidence in polypod adenomas of the same size. These lesions even when invasive do not show up against the translucent surrounding mucosa making endoscopic detection difficult. Dye spraying with indigo carmine makes their morphology clear, with well-circumscribed borders. Dye spraying and magnifying endoscopes can be used to observe pit patterns on the surface of the bowel. Combining dye spraying and high-resolution video endoscopy demonstrates well the colorectal epithelial surface. Scanning immersion video endoscopy visualizes the epithelial surface of the colorectal mucosa by high-resolution endoscopy after filling the lumen with water. Endoscopic ultrasound can be used to see if the lesion is intramucosal or not and assess the depth of invasion if malignancy is presented. Laser induced fluorescence spectroscopy has the potential to detect colonic dysplasia in vivo. Combining such technologies with conventional colonoscopy can help in the surveillance of large areas of colonic mucosa for the presence of dysplasia. Guided biopsy can replace random biopsy based on information provided at the time of colonoscopic examination.

  17. Endoscope drying and its pitfalls.

    PubMed

    Kovaleva, J

    2017-07-17

    Inadequate drying of endoscope channels is a possible cause of replication and survival of remaining pathogens during storage. The presence during storage of potentially contaminated water in endoscope channels may promote bacterial proliferation and biofilm formation. An incomplete drying procedure or lack of drying and not storing in a vertical position are the most usual problems identified during drying and endoscope storage. Inadequate drying and storage procedures, together with inadequate cleaning and disinfection, are the most important sources of endoscope contamination and post-endoscopic infection. Flexible endoscopes may be dried in automated endoscope reprocessors (AERs), manually, or in drying/storage cabinets. Flushing of the endoscope channels with 70-90% ethyl or isopropyl alcohol followed by forced air drying is recommended by several guidelines. Current guidelines recommend that flexible endoscopes are stored in a vertical position in a closed, ventilated cupboard. Drying and storage cabinets have a drying system that circulates and forces the dry filtered air through the endoscope channels. Endoscope reprocessing guidelines are inconsistent with one another or give no exact recommendations about drying and storage of flexible endoscopes. There is no conclusive evidence on the length of time endoscopes can be safely stored before requiring re-disinfection and before they pose a contamination risk. To minimize the risk of disease transmission and nosocomial infection, modification and revision of guidelines are recommended as required to be consistent with one another. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  18. Efficacy of pancreatic stenting prior to extracorporeal shock wave lithotripsy for pancreatic stones.

    PubMed

    Kondo, Hiromu; Naitoh, Itaru; Ohara, Hirotaka; Nakazawa, Takahiro; Hayashi, Kazuki; Okumura, Fumihiro; Miyabe, Katsuyuki; Shimizu, Shuya; Nishi, Yuji; Yoshida, Michihiro; Yamashita, Hiroaki; Umemura, Shuichiro; Hori, Yasuki; Kato, Akihisa; Joh, Takashi

    2014-07-01

    Extracorporeal shock wave lithotripsy is the first-line therapy for large pancreatic duct stones; however, it requires a long duration of therapy. To clarify the effect of pancreatic stenting prior to extracorporeal shock wave lithotripsy on shortening the duration of therapy and reducing complications. We retrospectively compared 45 patients who underwent pancreatic stenting prior to extracorporeal shock wave lithotripsy (stenting group) and 35 patients who did not undergo stenting prior to extracorporeal shock wave lithotripsy (non-stenting group) with regard to the cumulative number of shock waves required for stone fragmentation (stone size <3mm) and the rate of complications. The stenting group was associated with a significantly lower cumulative number of shock waves in univariate analysis (log-rank, p=0.046) and multivariate Cox proportional hazard analysis (hazard ratio, 1.88; 95% confidence interval, 1.13-3.14; p=0.015) than the non-stenting group. The frequency of pancreatitis tends to be lower in the stenting group than the non-stenting group (2.2% [1/45] vs 11.4% [4/35]; p=0.162). Pancreatic stenting prior to extracorporeal shock wave lithotripsy reduced the cumulative number of shock waves required for pancreatic stone fragmentation, and could be useful to shorten the duration of therapy. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  19. Present-day potentialities of endoscopic diagnostics and treatment of early cancer in respiratory and digestive tracts

    NASA Astrophysics Data System (ADS)

    Sokolov, Victor V.; Zharkova, Natalia N.; Filonenko, E. V.; Telegina, L. V.; Karpova, E. S.

    1999-12-01

    The paper presents the latest potentialities of the endoscopic fluorescent diagnostics as well as endoscopic electric-, laser surgery and photodynamic therapy (PDT) of the early cancer in the respiratory and digestive tracts. We present in detail indication and factors determining the application of the endoscopic resection of the tumor. The advantages of the combination application of PDT, electro-, Nd:YAG laser surgery and brachitherapy are stressed. The near and remote results of endoscopic treatment of the early cancer in larynx (37), lung (109), esophagus (39) and stomach (58) are shown.

  20. Combined endoscopic surgery in the prone-split leg position for successful single-session removal of an encrusted ureteral stent: a case report

    PubMed Central

    2014-01-01

    Introduction Although encrusted stents may lead to some unwanted complications including urinary tract obstruction, urinary sepsis, and potential loss of kidney function, there is currently no consensus on the most efficient method for managing stents that are intentionally left in situ. This is the first report describing the management of an encrusted stent using combined endoscopic surgery in the prone split-leg position in a single session. Case presentation A 47-year-old Asian man presented with left flank pain and macrohematuria. The patient had undergone left ureteral stenting three years previously for the treatment of left ureteral stones and hydronephrosis; however, he was lost to follow-up before the treatment for the ureter stones was completed. Therefore, the ureteral stent and stones were not removed. An abdominal radiograph and a noncontrast computed tomography scan showed encrustation along the retained stent with stone burdens in the kidney and ureter. The ureteral stent could not be removed by cystoscopy after shock wave lithotripsy of the left ureteral stones. Therefore, endoscopic lithotripsy combined with flexible ureteroscopy and miniature nephroscopy was performed with the patient in the prone split-leg position. All the stones and the encrusted ureteral stent were successfully removed in a single session. Conclusions In this case, percutaneous nephrolithomy in addition to flexible ureteroscopy was preferred because severe encrustation of the proximal stent and ureteral stones complicated the therapeutic strategy. Combined endoscopic techniques in the prone split-leg position can achieve successful and safe management of encrusted stents. PMID:24742133

  1. Matched pair analysis of ureteroscopy vs. shock wave lithotripsy for the treatment of upper ureteric calculi.

    PubMed

    Stewart, G D; Bariol, S V; Moussa, S A; Smith, G; Tolley, D A

    2007-05-01

    There is controversy over whether shock wave lithotripsy (SWL) or ureteroscopy (URS) is the best management of ureteric calculi, especially for stones located in the upper ureter. This study compares URS and SWL management of upper ureteric stones directly for the first time using a different analysis tool, the matched pair analysis study design. This method enables meaningful comparisons to be made on a small number of matched patients, using precise like-for-like matching. Adult patients undergoing primary treatment of solitary radiopaque proximal ureteric stones were identified. Patients with stents, nephrostomies or stones at the pelvi-ureteric junction were excluded. Patients had a minimum of 3 months follow-up. Patients treated by primary URS were matched using four parameters (sex, laterality, stone size and location) to patients treated on a Dornier Compact Delta Lithotriptor. A total of 1479 patients had URS or SWL from which 27 upper ureteric stone matched pairs were identified. Three-month stone free rates were 82% for URS and 89% for SWL (McNemar's test, p=0.625). Re-treatment was required in 11% and 26% following URS and SWL respectively (p=0.219). Forty-one per cent of URS patients required an ancillary treatment, such as stent removal, compared with only 22% of SWL patients (p=0.227). Introduction of a holmium:YAG laser for use with URS improved the stone free rate for URS to 100%. Using a robust like-for-like comparison of similar patients with very similar upper ureteric stones the outcomes following SWL and URS were comparable. Choice of treatment should therefore be based on parameters such as availability of equipment, waiting times and patient preference.

  2. Transient cavitation produced by extracorporeal shock wave lithotripsy

    NASA Astrophysics Data System (ADS)

    Cioanta, Iulian

    1998-12-01

    Two decades ago, a new medical procedure was introduced, allowing the fragmentation of kidney stones from outside the human body (noninvasively) using a shock wave device termed lithotripter ('stone crusher'). Considered as one of the most important medical inventions of this century, lithotripsy is currently used in more than 80% of urolithiasis cases. Experimental studies have shown that transient or inertial cavitation is generated by this procedure near the stones and in renal tissue. To find a correlation between the number of shocks delivered and the treatment efficiency, the acoustic emission (AE) generated by the oscillation of cavitation bubbles, and its relation with stone fragmentation and tissue damage during shock wave lithotripsy were studied. In vitro experiments were carried out to identify the correlation between the AE signals and the expansion and collapse of cavitation bubbles, which were captured by high-speed photography (20,000 frames per second). This correlation has been verified on four different electrohydraulic lithotripters, under multiple experimental conditions. The effects of tissue attenuation on AE and stone fragmentation were also studied. The in vitro results have further allowed the interpretation of AE signals from in vivo experiments with pigs. Although similar in general trend, in vivo AE signals are found to be shorter in expansion and longer in the total ringing times (including the rebound phenomenon) than for in vitro AE signals, indicating a tissue constraining effect on bubble oscillation. Based on this observation a new mechanism for renal vascular and tubular injury is proposed. In addition, changes in AE signals have been observed as the total number of shocks increases, and this dose dependence feature has allowed the determination of a threshold value for extended tissue injury at 20 kV. This result has been confirmed by histological analysis and by results of a theoretical model study of bubble oscillation in a

  3. In vitro comparison of shock wave lithotripsy machines.

    PubMed

    Teichman, J M; Portis, A J; Cecconi, P P; Bub, W L; Endicott, R C; Denes, B; Pearle, M S; Clayman, R V

    2000-10-01

    We tested the hypothesis that shock wave lithotripsy machines vary in the ability to fragment stones to small size. Calcium oxalate monohydrate, calcium hydrogen phosphate dihydrate, cystine and magnesium ammonium phosphate hexahydrate calculi were fragmented in vitro with the 22 kV. Dornier HM3, section sign 20 kV. Storz Modulith SLX, parallel, 15.6 kV. Siemens Lithostar C, paragraph sign 24 kV. Medstone STS-T,** 26 kV. HealthTronics LithoTron 160,daggerdagger 20 kV. Dornier Doli section sign and 22.5 kV. Medispec Econolithdouble daggerdouble dagger lithotriptors. Stones were given 500 or 2,000 shocks, or the Food and Drug Administration limit. Post-lithotripsy fragment size was characterized using sequential sieves and compared. Stone mass was statistically similar in the cohorts (p >0.94). Fragment size decreased as the number of shocks increased when the machine and stone composition were constant. Magnesium ammonium phosphate hexahydrate calculi were completely fragmented by all devices. At Food and Drug Administration treatment limits the mean incidence per device of calcium hydrogen phosphate dihydrate, calcium oxalate monohydrate, cystine and magnesium ammonium phosphate hexahydrate stones rendered into fragments greater than 2 mm. was 0% for the HM3, Modulith SLX and Lithostar C, 10% for the STS-T, 3% for the LithoTron 160, 29% for the Doli and 18% for the Econolith (p = 0. 04); 0% for the HM3, Modulith SLX, Lithostar C, STS-T and LithoTron 160, 4% for the Doli and 9% for the Econolith (p = 0.15); 1% for the HM3, 0% for the Modulith SLX, 1% for the Lithostar C, 10% for the STS-T, 14% for the LithoTron 160, 3% for the Doli and 9% for the Econolith (p = 0.44); and 1% for the HM3, 0% for the Modulith SLX, 1% for the Lithostar C, 10% for the STS-T, 14% for the LithoTron 160, 3% for the Doli and 9% for the Econolith (p = 0.44), respectively. Shock wave lithotriptors vary in fragmentation ability. The HM3, Modulith SLX and Lithostar C machines yield smaller

  4. Comparing the Efficacy and Safety of Ultrasonic Versus Pneumatic Lithotripsy in Percutaneous Nephrolithotomy: A Randomized Clinical Trial.

    PubMed

    Radfar, Mohammad Hadi; Basiri, Abbas; Nouralizadeh, Akbar; Shemshaki, Hamidreza; Sarhangnejad, Reza; Kashi, Amir Hossein; Narouie, Behzad; Soltani, Amir Mohammad; Nasiri, Mahmoudreza; Sotoudeh, Mehdi

    2017-02-01

    Percutaneous nephrolitotomy (PCNL) is the preferred treatment for large renal stones. There is a need for more comparative data for different lithotripters used in PCNL. To evaluate the comparative safety and efficacy of ultrasonic and pneumatic lithotripsy in patients undergoing PCNL. This randomized clinical trial was conducted at Labbafinejad University Hospital, Tehran, Iran. A total of 180 patients were selected and divided randomly into two groups: 88 patients to pneumatic and 92 to ultrasonic lithotripsy. Standard fluoroscopy-guided PCNL was performed using pneumatic or ultrasonic lithotripsy. The primary outcome was the procedure success rate. We also evaluated other outcome measures including operation time, stone fragmentation and removal time (SFRT), length of hospital stay, and postoperative complications. We used SPSS software version 18.0 for data analysis. The two groups were similar in baseline characteristics. There were no significant differences between the groups in stone fragmentation and removal time (p=0.63), stone free rate (p=0.44), and hospital stay (p=0.66). SFRT for hard stones was shorter using pneumatic lithotripsy (p<0.001). By contrast, ultrasonic lithotripsy was associated with a shorter SFRT for soft stones (p<0.001). Postoperative complications were similar in the two groups. A limitation of this study might be the 3-mo follow-up period. In general, there were no significant differences in the success rate and complications between pneumatic and ultrasonic lithotripsy. SFRT was significantly shorter using pneumatic lithotripsy for hard stones, and ultrasonic lithotripsy for soft stones. We found no significant differences in the success rate and complications of percutaneous nephrolitotomy using pneumatic and ultrasonic lithotripsy. Ultrasonic and pneumatic lithotripsy differed in the time for stone fragmentation and removal for hard and soft stones. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All

  5. Sparse aperture endoscope

    DOEpatents

    Fitch, Joseph P.

    1999-07-06

    An endoscope which reduces the volume needed by the imaging part thereof, maintains resolution of a wide diameter optical system, while increasing tool access, and allows stereographic or interferometric processing for depth and perspective information/visualization. Because the endoscope decreases the volume consumed by imaging optics such allows a larger fraction of the volume to be used for non-imaging tools, which allows smaller incisions in surgical and diagnostic medical applications thus produces less trauma to the patient or allows access to smaller volumes than is possible with larger instruments. The endoscope utilizes fiber optic light pipes in an outer layer for illumination, a multi-pupil imaging system in an inner annulus, and an access channel for other tools in the center. The endoscope is amenable to implementation as a flexible scope, and thus increases the utility thereof. Because the endoscope uses a multi-aperture pupil, it can also be utilized as an optical array, allowing stereographic and interferometric processing.

  6. Sparse aperture endoscope

    DOEpatents

    Fitch, J.P.

    1999-07-06

    An endoscope is disclosed which reduces the volume needed by the imaging part, maintains resolution of a wide diameter optical system, while increasing tool access, and allows stereographic or interferometric processing for depth and perspective information/visualization. Because the endoscope decreases the volume consumed by imaging optics such allows a larger fraction of the volume to be used for non-imaging tools, which allows smaller incisions in surgical and diagnostic medical applications thus produces less trauma to the patient or allows access to smaller volumes than is possible with larger instruments. The endoscope utilizes fiber optic light pipes in an outer layer for illumination, a multi-pupil imaging system in an inner annulus, and an access channel for other tools in the center. The endoscope is amenable to implementation as a flexible scope, and thus increases it's utility. Because the endoscope uses a multi-aperture pupil, it can also be utilized as an optical array, allowing stereographic and interferometric processing. 7 figs.

  7. Endoscopic resection of esthesioneuroblastoma.

    PubMed

    Gallia, Gary L; Reh, Douglas D; Lane, Andrew P; Higgins, Thomas S; Koch, Wayne; Ishii, Masaru

    2012-11-01

    Esthesioneuroblastoma, or olfactory neuroblastoma, is an uncommon malignant tumor arising in the upper nasal cavity. Surgical approaches to this and other sinonasal malignancies involving the anterior skull base have traditionally involved craniofacial resections. Over the past 10 years to 15 years, there have been advances in endoscopic approaches to skull base pathologies, including malignant tumors. In this study, we review our experience with purely endoscopic approaches to esthesioneuroblastomas. Between January 2005 and February 2012, 11 patients (seven men and four women, average age 53.3 years) with esthesioneuroblastoma were treated endoscopically. Nine patients presented with newly diagnosed disease and two were treated for tumor recurrence. The modified Kadish staging was: A, two patients (18.2%); B, two patients (18.2%); C, five patients (45.5%); and D, two patients (18.2%). All patients had a complete resection with negative intraoperative margins. Three patients had 2-deoxy-2-((18)F)fluoro-d-glucose avid neck nodes on their preoperative positron emission tomography-CT scan. These patients underwent neck dissections; two had positive neck nodes. Perioperative complications included an intraoperative hypertensive urgency and pneumocephalus in two different patients. Mean follow-up was over 28 months and all patients were free of disease. This series adds to the growing experience of purely endoscopic surgical approaches in the treatment of skull base tumors including esthesioneuroblastoma. Longer follow-up on larger numbers of patients is required to clarify the utility of purely endoscopic approaches in the management of this malignant tumor.

  8. Sterilization of endoscopic instruments.

    PubMed

    Sabnis, Ravindra B; Bhattu, Amit; Vijaykumar, Mohankumar

    2014-03-01

    Sterilization of endoscopic instruments is an important but often ignored topic. The purpose of this article is to review the current literature on the sterilization of endoscopic instruments and elaborate on the appropriate sterilization practices. Autoclaving is an economic and excellent method of sterilizing the instruments that are not heat sensitive. Heat sensitive instruments may get damaged with hot sterilization methods. Several new endoscopic instruments such as flexible ureteroscopes, chip on tip endoscopes, are added in urologists armamentarium. Many of these instruments are heat sensitive and hence alternative efficacious methods of sterilization are necessary. Although ethylene oxide and hydrogen peroxide are excellent methods of sterilization, they have some drawbacks. Gamma irradiation is mainly for disposable items. Various chemical agents are widely used even though they achieve high-level disinfection rather than sterilization. This article reviews various methods of endoscopic instrument sterilization with their advantages and drawbacks. If appropriate sterilization methods are adopted, then it not only will protect patients from procedure-related infections but prevent hypersensitive allergic reactions. It will also protect instruments from damage and increase its longevity.

  9. Novel focused OCT-LIF endoscope

    PubMed Central

    Wall, R. Andrew; Bonnema, Garret T.; Barton, Jennifer K.

    2011-01-01

    Combined optical coherence tomography (OCT) and laser-induced fluorescence (LIF) endoscopy has shown higher sensitivity and specificity for distinguishing normal tissue from adenoma when compared to either modality alone. Endoscope optical design is complicated by the large wavelength difference between the two systems. A new high-resolution endoscope 2 mm in diameter is presented that can create focused beams from the ultraviolet to near-infrared. A reflective design ball lens operates achromatically over a large wavelength range, and employs TIR at two faces and reflection at a third internal mirrored face. The 1:1 imaging system obtains theoretically diffraction-limited spots for both the OCT (1300 nm) and LIF (325 nm) channels. PMID:21412448

  10. [Shock wave lithotripsy, retrograde intrarenal surgery or percutaneous nephrolithotomy for lower pole renal stones?].

    PubMed

    Rojas, Alejandro; Gallegos, Héctor; Salvadó, José A

    2015-09-09

    Among the therapeutic alternatives available for the treatment of lower pole renal calculi are extracorporeal lithotripsy, percutaneous nephrolithotomy and retrograde intrarenal surgery. There is controversy about which of these techniques is more effective, especially for stones smaller than 20 mm. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified four systematic reviews including 11 pertinent randomized controlled trials overall. We combined the evidence and generated a summary of findings following the GRADE approach. We concluded percutaneous nephrolithotomy probably increases success rate, but it is not clear if it decreases the need of retreatment compared to extracorporeal shock wave lithotripsy. In comparison to retrograde intrarenal surgery, it may increase success rate, but it is not clear if it decreases the need of retreatment. Retrograde intrarenal surgery may increase success rate, and probably decreases need of retreatment compared to extracorporeal shock wave lithotripsy.

  11. Percutaneous transhepatic lithotripsy using a choledochoscope: long-term follow-up in 14 patients.

    PubMed

    Hayashi, N; Sakai, T; Yamamoto, T; Inagaki, R; Ishii, Y

    1998-11-01

    The purpose of our study was to estimate the long-term prognosis of patients with bile duct stones who undergo electrohydraulic lithotripsy guided by choledochoscopy. Since 1987, at our institution, 14 patients with bile duct stones have been treated using percutaneous electrohydraulic lithotripsy guided by choledochoscopy. The procedure was performed 5-7 days after biliary drainage using a 5-mm choledochoscope placed through an 18- to 20-French sheath. All patients underwent follow-up CT, sonography, or both every 6-12 months after treatment. No complications occurred in the 14 patients who underwent treatment. During a mean follow-up period of 4.8 years (range, 2-9 years), two (14%) of the 14 patients developed recurrent common bile duct stones, and another two (14%) developed recurrent small intrahepatic stones; all patients remained asymptomatic. Percutaneous electrohydraulic lithotripsy can be safely performed using a 5-mm choledochoscope. Recurrent calculi may be seen in 28% of patients.

  12. Massive Pulmonary Calculi Embolism: A Novel Complication of Pneumatic Lithotripsy: A Case Report.

    PubMed

    Zhang, Lin; Zhou, Yiwu

    2015-07-01

    Pneumatic lithotripsy is a minimally invasive technique mainly for the treatment of urinary staghorn stones. Previous literatures have reported some therapeutic complications during or after this procedure, but calculi embolism has not been mentioned before.We report here a fatal case of calculi-induced pulmonary embolism in an adult woman who underwent pneumatic lithotripsy. An autopsy did not reveal any evidence of pulmonary embolism. However, light microscopy revealed noticeable presence of calculi in pulmonary arterioles and capillaries, as evidenced by environmental scanning electron microscope and energy dispersive X-ray analysis. The primary determinants of calculi embolism include intrarenal pressure, and volume and viscosity of the calculi fragments formation. Vascular intravasation of smashed calculi might increase pulmonary vascular resistance and hypoxemia and decrease cardiac output.This case report intends to provide information for clinicians to consider the probability of intraoperative calculi embolism during lithotripsies when patients develop typical symptoms of acute pulmonary embolism.

  13. Microstructure inspection endoscope design

    NASA Astrophysics Data System (ADS)

    Liu, Na; Jing, Chao; Zhang, Hongxia; Zhang, Yimo; Jing, Wencai; Zhou, Ge

    2005-02-01

    A microstructure inspection endoscope, based on directly imaging, is proposed. It is designed for detecting defects on the surface of optical fiber end. It is matched with FC or SC female fiber connector. The inspection head of the endoscope can be put into a 2.5-millimeter-diameter micro-pore. Its numerical aperture is not restricted by tiny dimension of object lenses. System resolution is increased to 600 line-pairs per millimeter. The endoscope consists of object lenses, scanner slab and kohler illumination system. The design provides possibility of various utilities such as aiming at a smaller subject by micro optical scanner and modeling the surface by tri-dimensional vision. And the optical system includes low-magnification lenses and high-magnification zoom lenses. Rough observation at low-magnification and particularly inspection at high-magnification are provided. The instrument has the advantages of high identification, compact configuration and flexible manipulation.

  14. Physical mechanisms of importance to laser thrombolysis

    SciTech Connect

    Chapyak, E.J.; Godwin, R.P.

    1998-12-31

    Bubble dynamics plays a key role in many medical procedures including Laser Thrombolysis (L-T), acoustic and laser lithotripsy, interocular laser surgery, photoacoustic drug delivery, and perhaps ultrasonic imaging. The authors are investigating the effect that interfaces of different materials, especially biological and biomedical materials, have on the dynamics of nearby bubbles. Collapsing bubbles often become nonspherical, resulting in spectacular directed motion with potentially both beneficial and undesirable consequences. This directed motion may explain L-T mass removal and some types of laser-induced tissue damage.

  15. Slow vs rapid delivery rate shock wave lithotripsy for pediatric renal urolithiasis: a prospective randomized study.

    PubMed

    Salem, Hosni Khairy; Fathy, Hesham; Elfayoumy, Hanny; Aly, Hussein; Ghonium, Ahmed; Mohsen, Mostafa A; Hegazy, Abd El Rahim

    2014-05-01

    We compared slow vs fast shock wave frequency rates in disintegration of pediatric renal stones less than 20 mm. Our study included 60 children with solitary 10 to 20 mm radiopaque renal stones treated with shock wave lithotripsy. Patients were prospectively randomized into 2 groups, ie those undergoing lithotripsy at a rate of 80 shock waves per minute (group 1, 30 patients) and those undergoing lithotripsy at a rate of 120 shock waves per minute (group 2, 30 patients). The 2 groups were compared in terms of treatment success, anesthesia time, secondary procedures and efficiency quotient. Stone clearance rate was significantly higher in group 1 (90%) than in group 2 (73.3%, p = 0.025). A total of 18 patients in group 1 (60%) were rendered stone-free after 1 session, 8 required 2 sessions and 1 needed 3 sessions, while shock wave lithotripsy failed in 3 patients. By comparison, 8 patients (26.6%) in group 2 were rendered stone-free after 1 session, 10 (33.3%) required 2 sessions and 4 (13.3%) needed 3 sessions to become stone-free. Mean general anesthesia time was significantly longer in group 1 (p = 0.041). Postoperatively 2 patients in group 1 and 4 in group 2 suffered low grade fever (Clavien grade II). Significantly more secondary procedures (percutaneous nephrolithotomy, repeat shock wave lithotripsy) were required in group 2 (p = 0.005). The predominant stone analysis was calcium oxalate dihydrate in both groups. Efficiency quotient was 0.5869 and 0.3437 for group 1 and group 2, respectively (p = 0.0247). In children with renal stones slow delivery rates of shock wave lithotripsy have better results regarding stone clearance than fast delivery rates. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  16. A clinical nomogram to predict the successful shock wave lithotripsy of renal and ureteral calculi.

    PubMed

    Wiesenthal, Joshua D; Ghiculete, Daniela; Ray, A Andrew; Honey, R John D'A; Pace, Kenneth T

    2011-08-01

    Although shock wave lithotripsy is dependent on patient and stone related factors, there are few reliable algorithms predictive of its success. In this study we develop a comprehensive nomogram to predict renal and ureteral stone shock wave lithotripsy outcomes. During a 5-year period data from patients treated at our lithotripsy unit were reviewed. Analysis was restricted to patients with a solitary renal or ureteral calculus 20 mm or less. Demographic, stone, patient, treatment and 3-month followup data were collected from a prospective database. All patients were treated using the Philips Lithotron® lithotripter. A total of 422 patients (69.7% male) were analyzed. Mean stone size was 52.3±39.3 mm2 for ureteral stones and 78.9±77.3 mm2 for renal stones, with 95 (43.6%) of the renal stones located in the lower pole. The single treatment success rates for ureteral and renal stones were 60.3% and 70.2%, respectively. On univariate analysis predictors of shock wave lithotripsy success, regardless of stone location, were age (p=0.01), body mass index (p=0.01), stone size (p<0.01), mean stone density (p<0.01) and skin to stone distance (p<0.01). By multivariate logistic regression for renal calculi, age, stone area and skin to stone distance were significant predictors with an AUC of 0.75. For ureteral calculi predictive factors included body mass index and stone size (AUC 0.70). Patient and stone parameters have been identified to create a nomogram that predicts shock wave lithotripsy outcomes using the Lithotron lithotripter, which can facilitate optimal treatment based decisions and provide patients with more accurate single treatment success rates for shock wave lithotripsy tailored to patient specific situations. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  17. High-efficiency shock-wave generator for extracorporeal lithotripsy.

    PubMed

    Broyer, P; Cathignol, D; Theillère, Y; Mestas, J L

    1996-09-01

    In extracorporeal lithotripsy, the electro-acoustic efficiency of electrohydraulic generators is limited by the inductance of the electrical discharge circuit. A new shock-wave generator is described that uses a coaxial discharge line enabling electro-acoustic efficiency to be greatly increased. The line is built using a para-electric ceramic with a relative dielectric constant of 1700, manufactured for use in high-voltage impulse mode. A coaxial spark gap, with minimal inductance, has been developed to obtain the triggered breakdown of the discharge line. Shock waves are created with a coaxial electrode plugged directly into the spark gap and immersed in an electrolyte of degassed saline. Electrode gap and electrolyte resistivity are adjusted to match the resistivity of the electrolyte volume between the underwater electrodes to the characteristic impedance of the line. The discharge line generates in the medium a rectangular current pulse with an amplitude of about 6000 A and a rise time of 50 ns. Compared with conventional generators, measurements of the expansive peak pressure pulse show an increase of 105% at 10 kV, 86.5% at 12 kV and 34.5% at 14 kV charging voltage. Electro-acoustic efficiency is found to be 11% instead of 5.5% for a conventional discharge circuit.

  18. Extracorporeal shock wave lithotripsy: a study of renal stone differences.

    PubMed

    Powers, C J; Tinterow, M M; Burpee, J F

    1989-01-01

    The extracorporeal shock wave lithotriptor (ESWL or lithotriptor) is a new, revolutionary, noninvasive method of treating renal calculi. It offers a safer, cheaper and more effective method of treatment compared to the traditional open surgery. Its history dates back only to 1980--and to 1985 at HCA Wesley Medical Center in Wichita, where research is just beginning. Initial research focused on ESWL versus traditional open surgery, but more recent research is investigating elements within the ESWL treatment. This article presents an investigation of renal stone size in relation to number of ESWL treatments needed per stone, number of shock waves per treatment, length of hospital stay post-lithotripsy, and hospital costs per length of stay during HCA Wesley's first year of operation. The subjects in this study consisted of approximately every third patient who received an ESWL treatment and were grouped according to stone sizes of less than 2 cm and those greater than 2 cm. A questionnaire was used, and after data were collected from the patient's charts and billing, a t-test for independent samples was used for analysis.

  19. Principles and application of extracorporeal shock wave lithotripsy.

    PubMed

    Robinson, S N; Crane, V S; Jones, D G; Cochran, J S; Williams, O B

    1987-04-01

    The physics, instrumentation, and patient-care aspects of extracorporeal shock wave lithotripsy (ESWL) in the treatment of kidney stone disease are described. The kidney stone is located through the use of two integrated roentgenographic imaging systems. The x-ray tubes, fixed on either side of a tub of water in which the patient is partially immersed, are directed upward. The patient is maneuvered until the imaging systems indicate the kidney stone is within the second focus of the reflector and within the 1.5-cu cm target area. Once within this alignment, the stone is ready for shock wave treatment; general or regional anesthesia is used to immobilize the patient so that the position of the stone can be maintained within the focus of the shock wave. When the stone is repeatedly subjected to this high-energy force, it begins to disintegrate until fragments of less than 1 mm are left. ESWL can (1) disintegrate kidney stones of all types, (2) be efficiently transmitted over distances that allow the shock wave source to be outside the body, (3) safely pass through living tissue, and (4) be precisely controlled and focused into a small target area. ESWL is a safe, effective, and cost-saving treatment that can be used for 90% of all kidney stone disease that previously required surgery.

  20. Review on Lithotripsy and Cavitation in Urinary Stone Therapy.

    PubMed

    Ghorbani, Morteza; Oral, Ozlem; Ekici, Sinan; Gozuacik, Devrim; Kosar, Ali

    2016-01-01

    Cavitation is the sudden formation of vapor bubbles or voids in liquid media and occurs after rapid changes in pressure as a consequence of mechanical forces. It is mostly an undesirable phenomenon. Although the elimination of cavitation is a major topic in the study of fluid dynamics, its destructive nature could be exploited for therapeutic applications. Ultrasonic and hydrodynamic sources are two main origins for generating cavitation. The purpose of this review is to give the reader a general idea about the formation of cavitation phenomenon and existing biomedical applications of ultrasonic and hydrodynamic cavitation. Because of the high number of the studies on ultrasound cavitation in the literature, the main focus of this review is placed on the lithotripsy techniques, which have been widely used for the treatment of urinary stones. Accordingly, cavitation phenomenon and its basic concepts are presented in Section II. The significance of the ultrasound cavitation in the urinary stone treatment is discussed in Section III in detail and hydrodynamic cavitation as an important alternative for the ultrasound cavitation is included in Section IV. Finally, side effects of using both ultrasound and hydrodynamic cavitation in biomedical applications are presented in Section V.

  1. A heuristic model of stone comminution in shock wave lithotripsy

    PubMed Central

    Smith, Nathan B.; Zhong, Pei

    2013-01-01

    A heuristic model is presented to describe the overall progression of stone comminution in shock wave lithotripsy (SWL), accounting for the effects of shock wave dose and the average peak pressure, P+(avg), incident on the stone during the treatment. The model is developed through adaptation of the Weibull theory for brittle fracture, incorporating threshold values in dose and P+(avg) that are required to initiate fragmentation. The model is validated against experimental data of stone comminution from two stone types (hard and soft BegoStone) obtained at various positions in lithotripter fields produced by two shock wave sources of different beam width and pulse profile both in water and in 1,3-butanediol (which suppresses cavitation). Subsequently, the model is used to assess the performance of a newly developed acoustic lens for electromagnetic lithotripters in comparison with its original counterpart both under static and simulated respiratory motion. The results have demonstrated the predictive value of this heuristic model in elucidating the physical basis for improved performance of the new lens. The model also provides a rationale for the selection of SWL treatment protocols to achieve effective stone comminution without elevating the risk of tissue injury. PMID:23927195

  2. A heuristic model of stone comminution in shock wave lithotripsy.

    PubMed

    Smith, Nathan B; Zhong, Pei

    2013-08-01

    A heuristic model is presented to describe the overall progression of stone comminution in shock wave lithotripsy (SWL), accounting for the effects of shock wave dose and the average peak pressure, P+(avg), incident on the stone during the treatment. The model is developed through adaptation of the Weibull theory for brittle fracture, incorporating threshold values in dose and P+(avg) that are required to initiate fragmentation. The model is validated against experimental data of stone comminution from two stone types (hard and soft BegoStone) obtained at various positions in lithotripter fields produced by two shock wave sources of different beam width and pulse profile both in water and in 1,3-butanediol (which suppresses cavitation). Subsequently, the model is used to assess the performance of a newly developed acoustic lens for electromagnetic lithotripters in comparison with its original counterpart both under static and simulated respiratory motion. The results have demonstrated the predictive value of this heuristic model in elucidating the physical basis for improved performance of the new lens. The model also provides a rationale for the selection of SWL treatment protocols to achieve effective stone comminution without elevating the risk of tissue injury.

  3. Pediatric extracorporeal shock wave lithotripsy: Predicting successful outcomes

    PubMed Central

    McAdams, Sean; Shukla, Aseem R.

    2010-01-01

    Extracorporeal shock wave lithotripsy (ESWL) is currently a first-line procedure of most upper urinary tract stones <2 cm of size because of established success rates, its minimal invasiveness and long-term safety with minimal complications. Given that alternative surgical and endourological options exist for the management of stone disease and that ESWL failure often results in the need for repeat ESWL or secondary procedures, it is highly desirable to identify variables predicting successful outcomes of ESWL in the pediatric population. Despite numerous reports and growing experience, few prospective studies and guidelines for pediatric ESWL have been completed. Variation in the methods by which study parameters are measured and reported can make it difficult to compare individual studies or make definitive recommendations. There is ongoing work and a need for continuing improvement of imaging protocols in children with renal colic, with a current focus on minimizing exposure to ionizing radiation, perhaps utilizing advancements in ultrasound and magnetic resonance imaging. This report provides a review of the current literature evaluating the patient attributes and stone factors that may be predictive of successful ESWL outcomes along with reviewing the role of pre-operative imaging and considerations for patient safety. PMID:21369388

  4. Elimination of cavitation-related attenuation in shock wave lithotripsy

    NASA Astrophysics Data System (ADS)

    Sankin, G. N.; Lautz, J. M.; Simmons, W. N.; Zhong, P.; Frank, S. T.; Szeri, A. J.

    2017-03-01

    In shock wave lithotripsy (SWL), acoustic pulses with a leading compression wave followed by a tensile wave are delivered into the patient's body using a water-filled coupling cushion. Cavitation-related acoustic energy loss in the coupling unit depends critically on water conditions, e.g. dissolved gas concentration and exchange flow rate. We have systematically investigated the attenuation mechanism in the coupling water via pressure measurements and cavitation characterization. In non-degassed water the bubble cluster became progressively dense (i.e., proliferated because of gas diffusion into bubbles and splitting of bubbles into many daughter bubbles) in shock waves delivered at 1 Hz leading to reduction in the tensile wave duration from a nominal value of 4.6 to 1.8 µs. To reduce cavitation in the coupling water along the beam path, we have used a continuous jet flow to remove residual daughter bubbles between consecutive shocks. As a result, stone fragmentation efficiency was increased from 16±4% to 30±5% (p = 0.002) after 250 shocks. Such a hydrodynamic approach for tensile wave attenuation in the coupling water may be used to provide a flexible means for a novel treatment strategy with tissue protection.

  5. Extracorporeal shock wave lithotripsy: An opinion on its future

    PubMed Central

    Rassweiler, Jens; Rassweiler, Marie-Claire; Frede, Thomas; Alken, Peter

    2014-01-01

    The development of miniaturized nephroscopes which allow one-stage stone clearance with minimal morbidity has brought the role of shock wave lithotripsy (SWL) in stone management into question. Design innovations in SWL machines over the last decade have attempted to address this problem. We reviewed the recent literature on SWL using a MEDLINE/PUBMED research. For commenting on the future of SWL, we took the subjective opinion of two senior urologists, one mid-level expert, and an upcoming junior fellow. There have been a number of recent changes in lithotripter design and techniques. This includes the use of multiple focus machines and improved coupling designs. Additional changes involve better localization real-time monitoring. The main goal of stone treatment today seems to be to get rid of the stone in one session rather than being treated multiple times non-invasively. Stone treatment in the future will be individualized by genetic screening of stone formers, using improved SWL devices for small stones only. However, there is still no consensus about the design of the ideal lithotripter. Innovative concepts such as emergency SWL for ureteric stones may be implemented in clinical routine. PMID:24497687

  6. Pediatric extracorporeal shock wave lithotripsy: Predicting successful outcomes.

    PubMed

    McAdams, Sean; Shukla, Aseem R

    2010-10-01

    Extracorporeal shock wave lithotripsy (ESWL) is currently a first-line procedure of most upper urinary tract stones <2 cm of size because of established success rates, its minimal invasiveness and long-term safety with minimal complications. Given that alternative surgical and endourological options exist for the management of stone disease and that ESWL failure often results in the need for repeat ESWL or secondary procedures, it is highly desirable to identify variables predicting successful outcomes of ESWL in the pediatric population. Despite numerous reports and growing experience, few prospective studies and guidelines for pediatric ESWL have been completed. Variation in the methods by which study parameters are measured and reported can make it difficult to compare individual studies or make definitive recommendations. There is ongoing work and a need for continuing improvement of imaging protocols in children with renal colic, with a current focus on minimizing exposure to ionizing radiation, perhaps utilizing advancements in ultrasound and magnetic resonance imaging. This report provides a review of the current literature evaluating the patient attributes and stone factors that may be predictive of successful ESWL outcomes along with reviewing the role of pre-operative imaging and considerations for patient safety.

  7. Secondary shock wave emissions from cavitation in lithotripsy

    NASA Astrophysics Data System (ADS)

    Chitnis, Parag V.; Cleveland, Robin O.

    2005-04-01

    We investigate the role of secondary shock waves (SSWs) generated by cavitation in lithotripsy. Acoustic pressure was measured with a fiber optic probe hydrophone and cavitation using a dual passive cavitation detector (PCD) consisting of two confocal transducers. An artificial stone (~7 mm diameter and ~9 mm length) was placed at the focus of an electrohydraulic lithotripter. The fiber was inserted through a hole drilled through the stone so that the tip was at the proximal surface. SSWs were identified by matching the time of arrival to that of the inertial collapse signature acquired by the PCD. Measurements of SSWs were obtained for 50% of SWs fired at 20 kV and 1 Hz. The peak positive pressure for the SSW was p+=33.7+/-14.8 MPa, which was comparable to the pressure induced by the incident SW (p+=42.6+/-6 MPa). The peak pressure in water was p+=23.2+/-4.4 MPa. The PCD also recorded acoustic emissions from forced collapse of pre-existing bubbles caused by the incident SW. We propose that both the reflection from the semi-rigid stone boundary and SSW from the forced collapse contribute to the observed increase in the peak pressure of the incident SW in presence of a stone. [Work supported by NIH.

  8. Impact of learning curve on efficacy of shock wave lithotripsy.

    PubMed

    Lee, Courtney; Best, Sara L; Ugarte, Roland; Monga, Manoj

    2008-09-01

    The purpose of this study was to evaluate the impact of a radiographer's learning curve on extracorporeal shock wave lithotripsy (SWL) efficacy. Five registered technologists who were certified to assist in SWL procedures but had no prior lithotripter experience were evaluated during a 4-year period. Stone-free (no residual fragments on plain radiographic imaging), re-treatment and post-SWL procedure rates were evaluated for the first 3 years of radiographer employment. The overall stone-free rate increased from 55% (efficiency quotient [EQ] 45) in the first year to 68% (EQ 50) in the third year. The treatment success rate for the lower calyx increased from 50% (EQ 41) in the first year to 62% (EQ 44) in the third year. There was no difference in re-treatment or post-SWL procedure rates. Efficacy with SWL, as measured by stone-free rates, improved with increasing experience of the radiographer. Ongoing supervision and mentorship might be helpful in the first year of service.

  9. Tandem shock wave cavitation enhancement for extracorporeal lithotripsy

    NASA Astrophysics Data System (ADS)

    Loske, Achim M.; Prieto, Fernando E.; Fernández, Francisco; van Cauwelaert, Javier

    2002-11-01

    Extracorporeal shock wave lithotripsy (ESWL) has been successful for more than twenty years in treating patients with kidney stones. Hundreds of underwater shock waves are generated outside the patient's body and focused on the kidney stone. Stones fracture mainly due to spalling, cavitation and layer separation. Cavitation bubbles are produced in the vicinity of the stone by the tensile phase of each shock wave. Bubbles expand, stabilize and finally collapse violently, creating stone-damaging secondary shock waves and microjets. Bubble collapse can be intensified by sending a second shock wave a few hundred microseconds after the first. A novel method of generating two piezoelectrically generated shock waves with an adjustable time delay between 50 and 950 µs is described and tested. The objective is to enhance cavitation-induced damage to kidney stones during ESWL in order to reduce treatment time. In vitro kidney stone model fragmentation efficiency and pressure measurements were compared with those for a standard ESWL system. Results indicate that fragmentation efficiency was significantly enhanced at a shock wave delay of about 400 and 250 µs using rectangular and spherical stone phantoms, respectively. The system presented here could be installed in clinical devices at relatively low cost, without the need for a second shock wave generator.

  10. Dynamics of concerted bubble cluster collapse in shock wave lithotripsy

    NASA Astrophysics Data System (ADS)

    Pishchalnikov, Yuri A.; McAteer, James A.; Evan, Andrew P.; Sapozhnikov, Oleg A.; Cleveland, Robin O.; Colonius, Tim; Bailey, Michael R.; Crum, Lawrence A.

    2003-10-01

    Cavitation bubble cluster collapse at the surface of artificial kidney stones during shock wave lithotripsy was investigated in vitro by means of multiframe high-speed photography, passive cavitation detection (PCD), and pressure waveform measurements using a fiber-optic probe hydrophone (FOPH). It was observed that after the passage of the lithotripter shock pulse the stone was covered by numerous individual bubbles. During their growth phase the bubbles coalesced into bubble clusters, with the biggest cluster at the proximal face of the stone. High-speed camera images suggested that cluster collapse started at the periphery and ended with a violent collapse in a small region in the center of the surface of the stone. Shadowgraphy resolved numerous secondary shock waves emitted during this focused collapse. Shock wave emission during cluster collapse was confirmed by PCD. Measurement with the FOPH showed that these shock waves were typically of short duration (0.2 μs). The majority of the shock waves emanating from cluster collapse were low amplitude but some shock waves registered amplitudes on the order of the incident shock pulse (tens of MPa). [Work supported by NIH DK43881, DK55674.

  11. The problem of coupling in dry-head lithotripsy

    NASA Astrophysics Data System (ADS)

    Pishchalnikov, Yuri A.; McAteer, James A.; Neucks, Joshua S.; Pishchalnikova, Irina V.; Williams, James C.

    2007-04-01

    Recent in vitro studies have shown that air pockets can get trapped at the coupling interface of the treatment head in dry-head lithotripsy, and this can pose a significant barrier to transmission of shock wave energy to the focal zone. Breakage of model stones is very sensitive to the presence of air pockets at the coupling interface. The quality of routine coupling is highly variable, and it seems quite feasible that the way in which the coupling gel is applied may have a significant effect on the quality of coupling. Therefore, attempts to find the best coupling regime may be valuable to perform, and preliminary results of in vitro tests are presented in this report. Experiments were conducted using gel or castor oil as coupling agents. The test tank was coupled through a transparent Mylar membrane to the water-filled cushion of the treatment head, so that pockets of air trapped between the two coupling surfaces could be observed and photographed. It is shown that the quality of coupling can be improved by applying an excessive amount of gel to just the water cushion of the lithotripter, while applying gel to both the water cushion and the Mylar membrane typically gives poor coupling. Repeat decoupling and re-coupling substantially degraded the quality of coupling, reducing shock wave energy density at the target by ˜80%. It was also observed that using castor oil as a coupling medium does not guarantee air-free coupling.

  12. Drugs for Pain Management in Shock Wave Lithotripsy

    PubMed Central

    Bach, Christian; Zaman, Faruquz; Kachrilas, Stefanos; Kumar, Priyadarshi; Buchholz, Noor; Masood, Junaid

    2011-01-01

    Objective. With this review, we provide a comprehensive overview of the main aspects and currently used drugs for analgesia in shockwave lithotripsy. Evidence Acquisition. We reviewed current literature, concentrating on newer articles and high-quality reviews in international journals. Results. No standardized protocols for pain control in SWL exist, although it is crucial for treatment outcome. General and spinal anaesthesia show excellent pain control but are only recommended for selected cases. The newer opioids and nonsteroidal anti-inflammatory drugs are able to deliver good analgesia. Interest in inhalation anaesthesia with nitrous oxide, local anaesthesia with deep infiltration of the tissue, and dermal anaesthesia with EMLA or DMSO has recently rekindled, showing good results in terms of pain control and a favourable side effect profile. Tamsulosin and paracetamol are further well-known drugs being currently investigated. Conclusion. Apart from classically used drugs like opioids and NSARs, medicaments like nitrous oxide, paracetamol, DMSA, or refined administration techniques for infiltration anaesthesia show a good effectiveness in pain control for SWL. PMID:22135735

  13. Effect of Shock Wave Lithotripsy on Renal Hemodynamics

    NASA Astrophysics Data System (ADS)

    Handa, Rajash K.; Willis, Lynn R.; Evan, Andrew P.; Connors, Bret A.

    2008-09-01

    Extracorporeal shock wave lithotripsy (SWL) can injure tissue and decrease blood flow in the SWL-treated kidney, both tissue and functional effects being largely localized to the region targeted with shock waves (SWs). A novel method of limiting SWL-induced tissue injury is to employ the "protection" protocol, where the kidney is pretreated with low-energy SWs prior to the application of a standard clinical dose of high-energy SWs. Resistive index measurements of renal vascular resistance/impedance to blood flow during SWL treatment protocols revealed that a standard clinical dose of high-energy SWs did not alter RI during SW application. However, there was an interaction between low- and high-energy SWL treatment phases of the "protection" protocol such that an increase in RI (vasoconstriction) was observed during the later half of SW application, a time when tissue damage is occurring during the standard high-energy SWL protocol. We suggest that renal vasoconstriction may be responsible for reducing the degree of tissue damage that normally results from a standard clinical dose of high-energy SWs.

  14. Intraluminal bubble dynamics induced by lithotripsy shock wave

    NASA Astrophysics Data System (ADS)

    Song, Jie; Bai, Jiaming; Zhou, Yufeng

    2016-12-01

    Extracorporeal shock wave lithotripsy (ESWL) has been the first option in the treatment of calculi in the upper urinary tract since its introduction. ESWL-induced renal injury is also found after treatment and is assumed to associate with intraluminal bubble dynamics. To further understand the interaction of bubble expansion and collapse with the vessel wall, the finite element method (FEM) was used to simulate intraluminal bubble dynamics and calculate the distribution of stress in the vessel wall and surrounding soft tissue during cavitation. The effects of peak pressure, vessel size, and stiffness of soft tissue were investigated. Significant dilation on the vessel wall occurs after contacting with rapid and large bubble expansion, and then vessel deformation propagates in the axial direction. During bubble collapse, large shear stress is found to be applied to the vessel wall at a clinical lithotripter setting (i.e. 40 MPa peak pressure), which may be the mechanism of ESWL-induced vessel rupture. The decrease of vessel size and viscosity of soft tissue would enhance vessel deformation and, consequently, increase the generated shear stress and normal stresses. Meanwhile, a significantly asymmetric bubble boundary is also found due to faster axial bubble expansion and shrinkage than in radial direction, and deformation of the vessel wall may result in the formation of microjets in the axial direction. Therefore, this numerical work would illustrate the mechanism of ESWL-induced tissue injury in order to develop appropriate counteractive strategies for reduced adverse effects.

  15. Complementary approaches to decreasing discomfort during shockwave lithotripsy (SWL).

    PubMed

    Ngee-Ming, Goh; Tamsin, Drake; Rai, B P; Somani, B K

    2014-06-01

    Shock wave lithotripsy (SWL) is an established treatment for renal stones. Although non-invasive, it can cause significant pain and anxiety during the procedure. Our purpose was to review the literature to look at the effect of complimentary therapy in patients undergoing SWL and whether it led to a reduction in the requirement of analgesics and anxiolytics. A systematic review was performed on the use of acupuncture, auricular acupressure, transcutaneous electrical nerve stimulation (TENS) and music during SWL. Only prospective randomized controlled trials were selected. Two reviewers independently extracted the data from each study. Outcomes relating to analgesia requirement, anxiety and stone-free rates (SFR) were compared. Seven papers were identified reporting on 591 patients (acupuncture-3, TENS-1 and music-3). Pain control/analgesia requirement was significantly better in four studies (music-2, acupuncture-1, TENS-1). Significantly lower anxiety was noted in one study with music and two using acupuncture. No difference in SFR was noted with the use of complementary therapy. No major or minor side effects were noted. Complementary therapy for SWL can help lower analgesia requirement and the anxiety associated with it. However, it does not have any effect on the SFR.

  16. Advances in balloon endoscopes.

    PubMed

    Araki, Akihiro; Tsuchiya, Kiichiro; Watanabe, Mamoru

    2014-06-01

    In September 2003, a double-balloon endoscope (DBE) composed of balloons attached to a scope and an overtube was released in Japan prior to becoming available in other parts of the world. The DBE was developed by Dr. Yamamoto (1), and 5 different types of scopes with different uses have already been marketed. In April 2007, a single-balloon small intestinal endoscope was released with a balloon attached only to the overtube as a subsequent model. This article presents a detailed account of the development of these scopes up to the present time.

  17. Olecranon extrabursal endoscopic bursectomy.

    PubMed

    Tu, Chen G; McGuire, Duncan T; Morse, Levi P; Bain, Gregory I

    2013-09-01

    Olecranon bursitis is a common clinical problem. It is often managed conservatively because of the high rates of wound complications with the conventional open surgical technique. Conventional olecranon bursoscopy utilizes an arthroscope and an arthroscopic shaver, removing the bursa from inside-out. We describe an extrabursal endoscopic technique where the bursa is not entered but excised in its entirety under endoscopic vision. A satisfactory view is obtained with less morbidity than the open method, while still avoiding a wound over the sensitive point of the olecranon.

  18. Endoscopic Endonasal Odontoidectomy.

    PubMed

    Zoli, Matteo; Mazzatenta, Diego; Valluzzi, Adelaide; Mascari, Carmelo; Pasquini, Ernesto; Frank, Giorgio

    2015-07-01

    Odontoidectomy is the treatment of choice for irr