输尿管镜联合钬激光治疗输尿管上段结石:附205例报告

目的 探讨输尿管镜联合钬激光治疗输尿管上段结石的效果和安全性.方法 回顾性分析205例输尿管上段结石患者行输尿管硬镜钬激光碎石治疗的临床资料,其中男91例,女114例,结石位于单侧188例,双侧17例,炎性息肉引起输尿管腔明显狭窄者12例.结石长径0.8～1.4 cm.结果 192例一次性碎石成功,单次碎石成功率为93.7%(192/205).9例有较大结石碎片(4～6 mm)残留于肾或输尿管内,4例在碎石过程中结石冲入肾内,其中1例较大结石(1.4 cm)移位至肾盂后改行PCNL,其余3例留置双J管改行ESWL,均治愈.19例合并炎性息肉同期行激光烧灼.手术时间15~90min,平均30 min.住院时间2~9 d,平均3.5 d.198例患者在门诊获得随访,随访时间3～24个月,平均6个月,结石均排尽.结论 输尿管镜联合钬激光治疗输尿管上段结石的一种比较理想的腔内碎石技术,其碎石成功率高,并发症发生率低,创伤小,患者术后恢复快,而且可同期处理结石合并炎性息肉和狭窄.     

输尿管镜钬激光治疗输尿管纤维上皮息肉14例报告

目的：探讨输尿管镜钬激光治疗输尿管纤维上皮息肉的有效性和安全性。方法：应用输尿管镜钬激光技术治疗输尿管纤维上皮息肉患者14例，其中上段息肉10例，中、下段息肉各2例，并发输尿管结石9例。结果：术后随访3个月，12例疗效满意，肾积水明显改善．保护了肾功能；1例发生输尿管狭窄．1例残留结石。结论：输尿管镜钬激光技术是治疗输尿管纤维上皮息肉安全、有效的方法，但远期疗效尚需进一步研究。     

输尿管镜钬激光治疗小儿尿路结石19例报告

目的：探讨输尿管镜钬激光治疗小儿尿路结石的效果及并发症。方法：对19例小儿尿路结石（输尿管结石16例,膀胱结石3例）患者进行输尿管镜钬激光碎石治疗。结果：18例患儿均成功碎石并排出结石,1例将结石推入肾盂行ESWL术。19例患儿均无输尿管损伤和穿孔。结论：在明确掌握适应证和操作熟练的情况下,输尿管镜钬激光碎石是治疗小儿尿路结石的理想方法。     

输尿管镜钬激光内切开术治疗输尿管狭窄疗效分析

目的:探讨输尿管镜下钬激光内切开术治疗输尿管狭窄的临床疗效.方法:采用经输尿管镜钬激光内切开术治疗输尿管狭窄患者31例,术中留置F8双J管,术后2～3个月拔取双J管.结果:术后共随访28例,时间3～28个月.23例治愈,治愈率为82.1%(23/28).结论:输尿管镜钬激光内切开术治疗输尿管狭窄是一种疗效确切、安全微创的手术方法.     

Efficacy of percutaneous treatment of biliary tract calculi using the holmium:YAG laser

Background 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. Methods 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-μm 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. Results 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 requiring admission, and no deaths. Conclusions The use of PTHC with holmium:YAG laser ablation is safe and efficacious, but requires prolonged biliary access and often multiple procedures to ensure clearance of all calculi.     

输尿管肾镜钬激光碎石术治疗输尿管结石

目的　探讨输尿管肾镜钬激光碎石术治疗输尿管结石的有效性和安全性。　方法　回顾性分析 186例应用半硬性输尿管肾镜和钬激光碎石术治疗的输尿管结石患者资料。男 12 3例 ,女 6 3例 ;平均年龄 5 1岁。上段结石 5 1例 ,中段 6 4例 ,下段 71例。结石直径 0 .6～ 2 .5cm ,平均 1.3cm。　结果　单次碎石成功率为 96 % (179/ 186 ) ,其中上段结石单次碎石成功率为 90 % (46 / 5 1) ,中、下段为99 % (133/ 135 )。平均手术时间 2 8min ,术中无输尿管穿孔等并发症发生。 179例术后平均住院 1.2d。术后随访 2周～ 3个月 ,结石排净率 99% (177/ 179) ,肾盂积水由术前 (3.6± 0 .7)cm降至 (1.5± 0 .4 )cm(P <0 .0 1) ,无输尿管狭窄发生。　结论　输尿管肾镜钬激光碎石术治疗输尿管结石高效、安全 ,可作为输尿管结石特别是中下段结石首选的治疗方法。     

电刀和钬激光腔内切开对小猪肾盂输尿管连接部的形态学影响

目的探讨电刀和钬激光腔内切开小猪肾盂输尿管连接部(UPJ)后形态学的变化。方法采取大体、光学及电镜观察比较二种方式内切开后的愈合效果。结果大体观可见所有小猪UPJ处均未见尿性囊肿形成,与周围组织粘连轻微。电镜下均可见肌丝排列,大部分肌层已恢复连续性。光镜下见黏膜已恢复连续性,肌层的连续性的恢复主要限于内1／2～2／3区域。左右两侧评分分别为4．23±1．18和3．78±0．46,差异无统计学意义(P>0．05)。结论采用电刀和钬激光切割小猪UPJ后其形态学改变大致相同,在组织学愈合上差异无统计学意义(P>0．05)。     

Use of Nd:YAG laser in pancreatic resections with duodenal preservation in the dog

The trend in recent years for treatment of pancreatic carcinoma and occasionally for pancreatitis has been towards total pancreatectomy. The pancreas is also now being harvested for transplantation. Any operative technique that can reduce operating time, blood loss, and associated morbidity and mortality would be of tremendous advantage. The aim of this study was to undertake a total pancreatectomy using the Nd:YAG laser (wavelength 1,060 nm) with a helium neon laser (wavelength 628 nm) incorporated to provide a marker beam. The laser beam was passed into a 400 micron flexible glass fiber enclosed in a 2.5 mm polyethylene cannula, which also served as a conduit for coaxial CO2. The laser was operated in a continuous wave mode, and the fiber exit beam had a divergence of 10 degrees. For photocoagulation and tissue vaporization, peak powers of 50 W were used with 0.5-1 sec pulses. The total pancreatectomy using the Nd:YAG laser was performed in eight dogs, and ten dogs undergoing the conventional operative procedure served as controls. The findings indicate that the Nd:YAG laser could be used effectively and safely. The operating time was considerably diminished (P less than 0.01); the number of ligatures used was smaller; blood loss, graft survival, and duodenal viability were similar. The Nd:YAG laser offers a new therapeutic modality in the performance of tedious and often difficult pancreatic surgery.     

Nd:YAG laser hyperthermia treatment of rat mammary adenocarcinoma in conjunction with surface cooling

Electromagnetic radiation ranging from radiofrequency to microwave has classically been used to induce hyperthermia for treatment of cancer. This paper presents a new technique using near infrared radiation from an Nd:YAG laser in conjunction with surface cooling to induce hyperthermia in a rat tumor model. A CW Nd:YAG laser hyperthermia system was used to induce hyperthermic temperatures in chemically (DMBA) induced rat mammary adenocarcinomas. The laser was interfaced to a computer and a thermometry unit that provided feedback to control the tumor temperature between 43.2-43.5 degrees C. A thermocouple was placed at the base of the tumor and its temperature was used to control laser exposure. All tumors were 10 to 20 mm in diameter. Surface cooling methods investigated included forced air flow from a fan, forced oxygen flow plus an IV drip, and forced moist oxygen flow from a nebulizer. Twelve rat mammary adenocarcinomas have been treated with Nd:YAG laser hyperthermia. In 4 treatments, no surface cooling was employed. In one treatment the surface was cooled using oxygen flow plus IV drip. In 7 treatments the skin was cooled using the nebulizer technique. The nebulization provided the most effective and reproducible surface cooling. Nd:YAG laser hyperthermia delivered in conjunction with nebulizer surface cooling produced efficient heating of rat mammary adenocarcinomas. A mean temperature of 42.1 degrees C was obtained at the base of the tumors while the mean surface temperature was 37.0 degrees C.     

Treatment of ureteric lithiasis with retrograde ureteroscopy and holmium:YAG laser lithotripsy vs extracorporeal lithotripsy

OBJECTIVE

To analyse the efficiency of extracorporeal shockwave lithotripsy (ESWL) vs retrograde ureteroscopy and holmium:YAG laser lithotripsy, as ESWL is successful in 67–90% of cases but endoscopic lithotripsy with pneumatic lithotrites or lasers is successful in 90–96% of distal ureteric calculi, and holmium:YAG lithotripsy is effective in proximal ureteric calculi.

PATIENTS AND METHODS

From April 2006 to April 2008 we assessed 164 patients undergoing ureteric lithiasis in two homogeneous groups: group A included 83 treated with retrograde ureteroscopy and holmium:YAG endoscopic lithotripsy, and group B, 81 treated by ESWL. For laser lithotripsy we used 2071 mJ pulses at 3–6 Hz, with a mean of 1105 pulses and 2.5 kJ of total energy. ESWL was carried out using 37.5–87.5 mJ shock waves, a mean of 3650 shock waves and 187.6 J, with a radioscopy time of 1–4 min. The results were assessed after 3 weeks with plain films and ultrasonography, or urography. The efficiency of each procedure was assessed by calculating the relative risk, and results compared using the chi‐square or Student’s t‐test. The efficiency quotient (EQ) was determined for both procedures, and the focal applied energy quotient (FAEQ) used to assess ESWL.

RESULTS

The overall success rate for retrograde ureteroscopy and laser lithotripsy was 96.4% (80/83 patients), with an EQ of 0.52; a JJ catheter was placed in 67 patients. The success rate for the first ESWL session was 48%, and after repeat ESWL was 64% (52/81 patients), giving an EQ of 0.39. For successful treatments the FAEQ was 9.22, vs 6.47 for the failures (P < 0.005). There was a significant difference (P < 0.001) favouring laser lithotripsy, with an absolute benefit of 46% (95% confidence interval 33.8–57.9%), and number needed to treat of 2 (2–3), but no significant differences for lumbar ureteric calculi.

CONCLUSIONS

Endoscopic lithotripsy with the holmium laser is more effective than ESWL, but for lumbar ureteric calculi ESWL is therapeutically recommended as it is less invasive.     

输尿管镜下钬激光治疗梗阻性急性肾功能衰竭

目的:探讨输尿管镜下钬激光治疗上尿路结石梗阻并发急性肾功能衰竭的有效性和安全性。方法:应用输尿管镜直视下钬激光碎石术治疗输尿管结石梗阻并发急性肾功能衰竭患者12例。结果:术后患者血清尿素氮(BUN)、肌酐(Cr)均恢复正常或接近正常,尿量恢复正常,结石排净率92%(11/12)。结论:输尿管镜下钬激光治疗上尿路结石性梗阻并发急性肾功能衰竭具有安全、疗效可靠、损伤小、能同时处理双侧输尿管病变的优点,是急性梗阻性肾功能衰竭的有效治疗方法。     

Comparison of germanium oxide fibers with silica and sapphire fiber tips for transmission of erbium: YAG laser radiation

BACKGROUND AND OBJECTIVES: Endoscopic applications of the Erbium:YAG laser have been limited due to the lack of a suitable optical fiber delivery system. The purpose of this study was to compare the transmission of Er:YAG laser radiation through germanium oxide trunk fibers with silica and sapphire fiber tips for potential use in contact tissue ablation during endoscopy. STUDY DESIGN/MATERIALS AND METHODS: Er:YAG laser radiation with a wavelength of 2.94 microm, pulse length of 300 microseconds, pulse energies from 5 to 1,360 mJ, coupled into pulse repetition rates of 3-10 Hz, was through 1-m-long germanium oxide fibers with either 1-cm-long, 550-microm-diameter silica or sapphire tips. RESULTS: Transmission through the germanium oxide/sapphire fibers measured 65+/-5% compared with 55+/-4% for the germanium oxide/silica fibers (P<0.05). The damage threshold for the hybrid fibers averaged 309+/- 44 mJ and 126+/-43 mJ, respectively (n = 7 fibers each) (P<0.05). The highest pulse energies transmitted through the fibers were 700 mJ and 220 mJ, respectively. CONCLUSIONS: Improved index-matching of the trunk fiber and fiber tip at 2.94 microm resulted in higher transmission and damage thresholds for the germanium oxide/sapphire fibers. The germanium oxide/sapphire fiber may represent a promising mid-infrared optical fiber delivery system for use in endoscopic applications of the Er:YAG laser requiring a flexible, biocompatible, and robust fiber delivery system for contact tissue ablation.     

Nd:YAG laser induces long-term remission in transfusion-dependent patients with watermelon stomach

Watermelon stomach (gastric antral vascular ectasia) is a rare cause of gastric bleeding which can render patients transfusion-dependent. Laser therapy can be used to stop bleeding but the long-term success of this approach is not well described. We present a retrospective analysis of 24 consecutive transfusion-dependent patients who were treated in a national referral centre with Nd:YAG laser over an 18 year period. Laser therapy stopped all bleeding in 20 patients (83%) after a median of two sessions. Median follow up was 55 months (range 9–127). Patients remained transfusion free for a median of 16 months and a second course of treatment succeeded in all those who re-bled. One gastric perforation occurred early in the series and two patients developed pyloric stenosis which was successfully treated with balloon pyloric dilatation. Oestrogens were not used in these patients. Our experience shows that long-term remission from blood transfusion is seen in most patients treated with Nd:YAG laser. If bleeding recurs, further laser treatment is usually successful.     

Eye-safety requirements for Nd:YAG laser application in gastroenterology, urology, and neurosurgery

The preconditions relating to radiation safety for application of the Nd:YAG laser in the various fields of open and endoscopic surgery are studied. Potential eye hazards of clinical personnel using a Nd:YAG laser photocoagulator in surgical procedures are investigated and methods of eye protection are discussed. The amount of exposure of the eye to radiation back-scattered from stomach and bladder tissue, as can occur in clinical practice, has been determined for several commercially available rigid cystoscopes and flexible gastroscopes. In addition, the amount of back-scatter from brain and liver tissue has been established under the usual surgical working conditions. The International Electrotechnical Commission (IEC) and the American National Standard Institute (ANSI) provisions relating to laser safety are briefly explained in relation to the use of the Nd:YAG laser. The results of experimental investigations are compared with the maximum permissible exposure (MPE) limiting values as per the IEC and ANSI drafts. The precautions necessary for safe application of the Nd:YAG laser in the various medical spheres are described.     

输尿管镜钬激光碎石治疗肉芽包裹输尿管结石(附358例报告)

目的:探讨输尿管镜钬激光碎石治疗肉芽包裹输尿管结石的有效性和安全性.方法:分析2002年4月～2007年5月输尿管镜下钬激光碎石治疗肉芽包裹输尿管结石358例患者临床资料,对碎石率、排石率和并发症等进行统计分析.结果:共行367例次输尿管镜钬激光碎石,一次碎石成功率为93.2%(342/367),输尿管上段与中、下段结石一次碎石成功率分别为87%(94/108)、95.7%(248/259);平均手术时间36 min,平均碎石时间14 min;结石移位改行ESWL 8例,输尿管镜未窥见结石改行微创经皮肾镜取石6例,改开放手术取石6例;碎石过程中黏膜撕裂4例、黏膜下假道形成6例,输尿管穿孔6例;24例术后发热(体温＞38.5℃,持续2天以上),3例出现感染性休克;术后住院2～4天;1个月后拔除双J管,复查B超、KUB、IVP,结石排净率96.4%(354/367),肾盂积水由(3.8±0.6)cm降至(1.4±0.4)cm(P＜0.01);4例出现输尿管狭窄.结论:输尿管镜钬激光碎石治疗肉芽包裹输尿管结石疗效确切、安全,是治疗肉芽包裹输尿管结石,尤其是中、下段肉芽包裹输尿管结石的有效微创手段.     

Q开关Nd：YAG激光治疗太田痣1496例疗效分析

目的：回顾性分析Q开关Nd：YAG激光治疗仪治疗太田痣的疗效和安全性。方法：分析2006年3月～2011年3月笔者科室运用Q开关激光仪治疗1496例太田痣患者的临床疗效,根据治疗前后照片进行对比分析。结果：1496例太田痣经4～10次治疗,痊愈1311例,显效132例,有效53例,总有效率为100%。12例出现一过性色素沉着,所有患者均未出现严重不良反应。结论：Q开关Nd：YAG激光治疗太田痣安全、有效,治疗次数与疗效成正比相关,治疗次数越多,效果越好。     

A novel method of drug delivery for fibrinolysis with Ho:YAG laser-induced liquid jet

. Two of the problems inherent in the treatment of cerebral emboli are the narrow therapeutic time window and the severe side effects of fibrinolytic drugs. Thus, it is necessary to develop a new method of removing a cerebral thrombus more rapidly and with smaller quantities of fibrinolytics. The behaviour of a bubble formed by holmium (Ho):YAG laser irradiation in a capillary tube filled with pure water was observed at various stand-off distances (L; distance between the end of optical fibre and the capillary exit). Subsequently, a liquid-jet generator was created by insertion of an optical fibre (core diameter: 0.6 mm) into a catheter (6 Fr) filled with pure water, and a pulsed Ho:YAG laser (pulse duration time=350 μs, laser energy=230 mJ/pulse) was used to irradiate the optical fibre. The maximum penetration depth, into a gelatin artificial thrombus, of a liquid jet generated with this device was measured for various stand-off distances. Additionally, the phenomenon and the pressure around the catheter exit were captured via shadowgraph and PVDF needle hydrophone, respectively. The laser-induced bubble in the capillary tube grew rapidly in the direction of propagation and generated a liquid jet. The maximum penetration depth of this liquid jet into an artificial thrombus increased in proportion to L and reached a maximum value (9 mm) when L was around 13 mm. A shock wave whose overpressure at a point 4 mm away from the catheter exit exceeded 12 MPa was captured by shadowgraph. It was concluded that Ho:YAG laser irradiation within a water-filled catheter caused liquid jet formation, which could penetrate straight into an artificial thrombus. Hence, this jet is expected to promote fibrinolysis by means of injecting fibrinolytics deeply into the thrombus. After resolving some problems, this system will be applied to an endovascular therapy for cerebral embolisms in the near future. Paper received 6 August 2001; accepted after revision 14 December 2001.