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101.
本文报道纤维胆道镜治疗手术后残余结石42例,总有效率达到95.2%,结石取净率85.7%。评价了内镜取石的临床价值,认为是目前清除胆管残余结石最有效的方法,结果证明疗效良好。并分别介绍了肝外、肝内胆管结石、嵌顿性结石等的取石技术操作要领及难点,以及预防并发症的措施。  相似文献   
102.
Ureteroscopy offers an extension of endoscopic diagnosis and treatment to upper urinary tract malignancy. Combination of ureteroscopy and the Nd:YAG laser permits accurate and effective treatment of ureteral neoplasms. Nine highly selected patients, six males and three females, were treated with low grade papillary transitional cell carcinomas of the ureter with at least 24 months follow-up. Follow-up cytology and IVP have indicated no evidence for disease recurrence between the follow-up periods and minimal morbidity to the ureteroscopy and laser treatment. © 1993 Wiley-Liss, Inc.  相似文献   
103.
Limiting the number of oocytes transferred at gamete intra-Fallopiantransfer (GIFT) has limited the incidence of high-order pregnancybut at the same time compromised the fertility potential ofsome patients. A review of 300 patients who have undergone GIFTusing a flexible approach as to the number of oocytes transferredidentifies the patients at risk of high-order pregnancy as thoseaged under 30 years hi whom more than six oocytes are returnedand whose partner's spermatozoa have high progressive motUity.  相似文献   
104.
PURPOSE: Loss of active deflection with insertion of a holmium laser fiber can significantly decrease the efficacy of intrarenal flexible ureteroscopy. We evaluated the impact of inserting a novel, temperature activated, deflectable laser sheath on active deflection and flow rates. METHODS AND MATERIALS: Active deflection of 5 flexible ureteroscopes was measured with an empty channel and following separate insertions of 2, 272 mum holmium fibers. Insertion of the same fibers was then repeated through a proprietary, temperature activated, coiling nitinol sheath. Active deflection of the sheath following insertion into the working channel was achieved by a rapid flush of 10 cc hot water (60C) through the irrigation side port. Release of active deflection was obtained by repeating this maneuver with cold water (15C). Degrees of deflection were measured in triplicate. Flow rates were measured at 100 cm H2O pressure. RESULTS: Active deflection with an empty working channel decreased significantly with insertion of the 2 laser fibers (12 to 32 degrees). Insertion of the laser fiber through the nitinol sheath followed by temperature activation of the sheath maximized active deflection beyond baseline measures with the laser fibers by up to 60 degrees. Flow rates in all ureteroscopes decreased significantly with the use of the Powerflex sheath (Optical Integrity, Panama City, Florida) but it remained above 12 ml per minute in all ureteroscopes. CONCLUSIONS: A temperature activated, deflectable nitinol sheath facilitates active deflection with a 272 mum holmium laser fiber in the working channel of the flexible ureteroscope, suggesting strong potential for clinical evaluation.  相似文献   
105.
OBJECTIVE: To present early experience in managing complex renal calculi using a combined ureteroscopic and percutaneous approach, as complex and branched renal calculi often require multiple access tracts during percutaneous nephrolithotomy (PNL), and the combined use of flexible ureteroscopy and PNL has the potential to reduce the inherent morbidity of several tracts. PATIENTS AND METHODS: The study included seven patients (mean age 54 years) with multiple, branched, large-volume renal calculi suitable for management with PNL. Preoperative data, including patient demographics, stone location and stone surface area, were recorded. After informed consent, the patients underwent combined PNL and ureteroscopy in one session. Intraoperative data, including the location of PNL puncture sites, operative duration and complications, were analysed. Stone-free rates were determined by follow-up imaging at 3 months. RESULTS: All patients had either two or more stones in separate locations in the collecting system, or staghorn stones involving multiple calyces. The mean stone burden was 666 mm(2). All patients had only one percutaneous access tract. The mean operative duration was 142 min and the mean blood loss 79 mL. Two patients had small residual stones (< 3 mm), that required ureteroscopic intervention as they failed to pass spontaneously by 3 months after the initial combined procedure. The convalescence was similar to that in our current PNL practice; imaging showed that five of the patients were stone-free. CONCLUSIONS: Combined PNL and ureteroscopic management can effectively reduce the number of percutaneous access tracts which would otherwise be required for managing complex and branched renal calculi, as stones in an unfavourable location relative to the access tract can be relocated and fragmented within easy reach of the single nephrostomy tract. This manoeuvre reduces potential patient morbidity and blood loss but with no significant effect on stone-free rates and operative durations.  相似文献   
106.

OBJECTIVE

To highlight the current status of ureteroscopic endoureterotomy (UE) by reporting extensive experience with the endoscopic management of ureteric strictures, with special emphasis on factors determining success, and by reviewing publications on the minimally invasive management of ureteric strictures.

PATIENTS AND METHODS

The study comprised 50 patients (mean age 53 years, range 18–85, equal sex distribution) with ureteric strictures of varying causes; all had their stricture treated endoscopically. The follow‐up was 0.5–9 years; 10 patients with recurrent strictures had two ipsilateral stents placed to try to improve the outcome, and eight patients with completely obliterating strictures were treated by ureteroscopic re‐canalization.

RESULTS

The site of stricture had no bearing on the eventual outcome. Patients with uretero‐enteric and malignant strictures did not fare so well. The most important predictor of failure was the length of the stricture, with failure in all seven patients with strictures of > 2 cm. In the 10 patients treated with two ipsilateral stents, eight were successful, which was very promising considering that these patients had recalcitrant strictures and placing one stent had previously failed. The overall success rate was 74%.

CONCLUSION

UE has become the procedure of choice for the initial management of ureteric strictures. Simple balloon dilatation is also effective in certain situations. The characteristics of the stricture often govern the eventual outcome. In properly selected cases success rates of ≈ 75% can be expected.
  相似文献   
107.
Fiberoptic intubation of the spontaneously breathing patient is the gold standard and technique of choice for the elective management of a difficult airway. In the hands of the properly trained and experienced user, it is also an excellent 'plan B' alternative when direct laryngoscopy unexpectedly fails. Fiberscope-assisted intubation through an endoscopy face mask, laryngeal mask airway or intubating laryngeal mask airway secures ventilation and oxygenation, and permits endotracheal intubation in airway emergency situations. Portable fiberscopes can be used in remote settings, increasing patient safety. This review discusses current fiberoptic intubation techniques and their applications in the management of both the anticipated and unanticipated difficult airway.  相似文献   
108.
PURPOSE: Percutaneous nephrolithotripsy is standard treatment for renal calculi greater than 2 cm. Modern flexible ureteroscopes using the complementary effects of electrohydraulic (EHL) and Ho:YAG laser lithotrites can treat 2 to 4 cm renal calculi in minimally invasive fashion with similar or superior results. We evaluated the safety and efficacy of ureteroscopic nephrolithotripsy for the management of 2 to 4 cm renal calculi in a community setting. MATERIALS AND METHODS: Between January 2001 and November 2002 all 15 patients presenting with renal calculi 22 to 42 mm long (mean 33) and 275 to 650 mm in area (mean 396), of whom 40% had infection, underwent flexible ureteroscopic nephrolithotripsy. A total of 13 patients had 3-month followup data. Hard stone components, namely calcium oxalate monohydrate and/or apatite, were present in 13 cases (87%). Treatment principles were the aggressive treatment of infection, EHL stone debulking, Ho:YAG laser lithotripsy to weaken hard stones structurally, manual piston irrigation to maintain visibility, bladder drainage to maintain low intrarenal pressures, minimum 6-hour postoperative observation and physiological passage of stone fragments. RESULTS: In the 13 patients with 3-month followup data the stone clearance rate was 92% for complete stone free status and 100% for fragments less than 4 mm. This result was achieved at 1 stage in 10 cases 13 (77%) and at 2 to 4 stages in 1 each. Mean procedure time per stage was 47 minutes (range 25 to 90) and total procedure time per patient was 66 minutes (range 25 to 240). There was no significant change in mean preoperative and postoperative hemoglobin (p = 0.87) and creatinine (p = 0.85) in the 16 of 21 procedures for which data were available. Procedures were done on an outpatient basis except in 1 patient, who was hospitalized overnight for the management of preexisting pulmonary problems. One rehospitalization for colic management but no other unplanned emergency department or clinic visits occurred. All patients were rendered infection-free and symptom-free. CONCLUSIONS: Combined EHL and Ho:YAG laser flexible ureteroscopic lithotripsy can be an effective treatment with low morbidity. As such, it provides an attractive, minimally invasive alternative to percutaneous nephrolithotripsy or open surgery in patients with 2 to 4 cm renal calculi.  相似文献   
109.
Introduction Problems associated with common treatment modalities of bone cysts located in the proximal femur include a high blood loss, infection, lack of stability, donor-site morbidity, restriction to normal activity, and high recurrence rate.Materials and methods Twelve patients with a simple bone cyst of the proximal femur were treated with retrograde flexible nailing. Six showed a pathological fracture. Mean age at surgery was 10.4 years, mean follow-up was 57 months. Radiographs were classified as healed, healed with residuals, recurred, or no response.Results The mean healing period was 38.8 months. Two cysts healed completely, nine healed with residuals. There was no recurrence or non-responder. In a fractured cyst a perforation of a nail through the cyst occurred 4 months after nailing.Conclusion The method is less invasive and offers early stability to the bone without the need for cast immobilization.None of the authors received financial support for this study.This study was conducted at the Department of Paediatric Orthopaedic Surgery, Medical University, Graz, Austria.A. Roposch is the recipient of the Research Training Competition Award, Population Health Sciences Program, Hospital for Sick Children, Toronto, Canada.  相似文献   
110.
Summary: We describe the synthesis and characterization of a soluble photoreactive polyimide. The precursor of the polyimide was prepared from 2,2′‐bis{4‐(3,4‐dicarboxyphenoxy)phenyl}hexafluoropropane dianhydride and 3,3′‐hydroxy‐4,4′‐diaminobiphenyl; the photoreactive polyimide was then prepared by the polymer reaction of the hydroxyl groups in the precursor polymer with 2‐{2‐[4‐(6‐hydroxyhexyloxy)phenyl]ethenyl}pyridine as a photoreactive 2‐styrylpyridine derivative. The photoreactive polymer and its precursor polymer were soluble in various polar organic solvents, and their thin flexible films were easily formed by solution casting. The initial decomposition temperatures of the former and latter polymers were 350 and 470 °C, respectively. The extent of the photochemical reaction of the photoreactive polymer film was measured to be 65.8% at an exposure energy of 1.5 J/cm2. The transmittance of the film was found to be approximately 92% at room temperature and approximately 85% at 200 °C. These results suggest that the polyimide is a photosensitive polymer with good photosensitivity and high optical transparency. The dichroic ratios of the film were between 0.023 and 0.025 when exposed to linearly polarized UV light (LPUVL). The liquid crystal in the film cell was perpendicularly oriented to the electric vector of LPUVL.

Polar diagrams of LC cells fabricated from polyimide 6FBPA‐HAB‐SP6 film after irradiation with LPUVL.  相似文献   

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