Transurethral Balloon Laser Prostatectomy in the Canine: Medium-Term,Follow-Up Results

Background and Objective: To demonstrate surgical complications in transurethral balloon laser prostatectomy by medium-term, follow-up observation. Study Design/Materials and Methods: Three dogs were treated with transurethral laser irradiation using 15 watts for 20 minutes at 60°C at a 5 mm depth of the prostate, one dog was for 5 minutes with same parameters, and one dog was with only laser balloon probe as a control. All animals were followed for 24 weeks. Results: A large cavity in the prostatic urethra was formed in laser-treated animals 4 weeks later, whereas the cavity in the balloon-treated animals was not shown. Cavity volume did not significantly change for 6 months, and there was no bladder neck stricture or urethral stenosis observed in any case. An increase in collagen fibers in the periurethral tissue was barely observed by Mallory staining. Conclusion: The risk of bladder neck stricture and urethral stenosis was estimated to be low for transurethral balloon laser prostatectomy. © 1995 Wiley-Liss, Inc.     

TRANSURETHRAL BALLOON LASER HYPERTHERMIA FOR CHRONIC NON-BACTERIAL PROSTATITIS: A CLINICAL TRIAL

Transurethral balloon laser hyperthermia (TUBAL-H) was performed on five patients with chronic non-bacterial prostatitis who failed to respond to conventional treatment administered for more than two years. The prostatic interstitial temperature during treatment was measured and the safety and efficacy of this treatment was assessed. TUBAL-H was performed at a target temperature of 43°C (5 mm depth) and at a laser power of 30 watts with urethral cooling for 20 min in the first three patients and for 30 min in the remaining two patients. The prostatic interstitial temperature at a depth of about 5 mm from the urethral surface ranged from 40.5 to 43.0°C during treatment. The temperature of the urethra ranged from 31.5 to 39°C and that of the rectum remained below 39.5°C. After treatment, no abnormal findings were noted in any of the hematological and biological tests carried out, including prostatic specific antigen. The leukocyte count in expressed prostatic secretions fell to less than five cells per high-power field in four of the five patients after three months. A complete improvement in symptoms was observed in one patient, partial improvement in three, and no improvement in one. Based on these results, TUBAL-H was considered to be safe and a suitable treatment for patients with chronic prostatitis.     

犬尿道狭窄动物模型的建立

目的制作犬尿道狭窄动物模型。方法健康雄性成年犬15只，10g／L戊巴比妥钠（30mg／kg）静脉麻醉后，切开阴茎腹侧包皮，逆行尿道造影，随机抽取3只犬设为对照组，同步观察，余12只犬为试验组，以好克公司F10小儿电切镜直视下行前尿道电切术。术后第15和30天时分别麻醉动物，做尿道镜及尿道造影检查，评价模型制作效果。结果1只（8．3％）犬死于术后尿道感染，3只（25％）犬术后当天发生尿潴留，术后第15天，4只（36．3％）犬在尿道损伤部位发生瘢痕性狭窄，术后30d，存活的11只（91．7％）犬全部出现尿道狭窄，对照组犬尿道正常。结论采用小儿电切镜制造犬前尿道损伤能成功制作出尿道狭窄动物模型，为瘢痕性尿道狭窄的发生机理和分子生物学研究提供实验对象。     

The risk of intra-urethral Foley catheter balloon inflation in spinal cord-injured patients: Lessons learned from a retrospective case series

Background

Inflating the balloon of Foley catheter in urethra is a complication of urethral catheterisation. We report five patients in whom this complication occurred because of unskilled catheterisation. Due to lack of awareness, the problem was not recognised promptly and patients came to harm.

Case series

1. 1.
   A tetraplegic patient developed pain in lower abdomen and became unwell after transurethral catheterisation. CT pelvis revealed full bladder with balloon of Foley catheter in dilated urethra.
    
2. 2.
   Routine ultrasound examination in an asymptomatic tetraplegic patient with urethral catheter drainage, revealed Foley balloon in the urethra. He was advised to get catheterisations done by senior health professionals.
    
3. 3.
   A paraplegic patient developed bleeding and bypassing after transurethral catheterisation. X-ray revealed Foley balloon in urethra; urethral catheter was changed ensuring its correct placement in urinary bladder. Subsequently, balloon of Foley catheter was inflated in urethra several times by community nurses, which resulted in erosion of bulbous urethra and urinary fistula. Suprapubic cystostomy was performed.
    
4. 4.
   A tetraplegic patient developed sweating and increased spasms following urethral catheterisations. CT of abdomen revealed distended bladder with the balloon of Foley catheter located in urethra. Flexible cystoscopy and transurethral catheterisation over a guide-wire were performed. Patient noticed decrease in sweating and spasms.
    
5. 5.
   A paraplegic patient developed lower abdominal pain and nausea following catheterisation. CT abdomen revealed bilateral hydronephrosis and hydroureter and Foley balloon located in urethra. Urehral catheterisation was performed over a guide-wire after cystoscopy. Subsequently suprapubic cystostomy was done.
    

Conclusion

Spinal cord injury patients are at increased risk for intra-urethral Foley catheter balloon inflation because of lack of sensation in urethra, urethral sphincter spasm, and false passage due to previous urethral trauma. Education and training of doctors and nurses in proper technique of catheterisation in spinal cord injury patients is vital to prevent intra-urethral inflation of Foley catheter balloon. If a spinal cord injury patient develops bypassing or symptoms of autonomic dysreflexia following catheterisation, incorrect placement of urethral catheter should be suspected.

     

Transurethral Balloon Laser Thermotherapy: Effects of a Directionally Shielded Balloon in Canine Prostates

Background : Transurethral balloon laser thermotherapy (TUBAL-T) improves objective, but not subjective, symptoms of benign prostatic hyperplasia (BPH). We studied whether or not an Nd:YAG laser beam with a shielded balloon could successfully irradiate the prostate during TUBAL-T in a selective manner, to improve the subjective symptoms. Methods : TUBAL-T was performed on canine prostates using the balloon with a laser probe, which was shielded anteriorly at 90 degrees (from the center of the balloon) and posteriorly at 90 degrees. Results : At 20 watts laser power, the relative power density in the bilateral non-shielded areas was 17.4 and 17.8, and in the shielded area it was 1.0. Observation by thermography revealed that the temperature after laser radiation in a non-shielded area of a fish cake phantom was higher than in a shielded area. Following transurethral thermotherapy using a shielded balloon in dogs, a cavity was formed bilaterally around the urethra, and the tissues at the anteroposterior sides and the urethra were preserved. Conclusions : TUBAL-T, which has been performed in clinical cases of benign prostatic hyperplasia, might be useful in selective irradiation of adenoma if a shielded balloon is used.     

In vitro effects of pulsed holmium laser energy on canine uroliths and porcine cadaveric urethra

BACKGROUND AND OBJECTIVES: To assess the effect of holmium laser energy on canine uroliths and porcine urethra. STUDY DESIGN/MATERIALS AND METHODS: Uroliths of known composition and fresh cadaveric urethra were exposed to holmium laser energy. Urolith fragmentation times and depth of urethral lesions were determined. RESULTS: Overall mean fragmentation time was 11.8 +/- 8.01 seconds. Magnesium ammonium phosphate (MAP) and urate uroliths had significantly shorter fragmentation times compared to other uroliths. Fragmentation time of MAP uroliths irradiated with 1.2 J/pulse was significantly longer than the fragmentation time of MAP uroliths irradiated with 0.3 J/pulse. Overall mean lesion depth for urethral specimens treated with 90 degrees contact mode irradiation was significantly greater than overall mean lesion depth for specimens treated with 30 degrees non-contact mode. CONCLUSIONS: Holmium laser energy effectively fragmented canine uroliths and caused minimal urethral damage in vitro. Dogs with urolithiasis may represent a useful animal model for developing human lithotripsy procedures.     

犬尿道瘢痕组织中TGF—β1和MMP-1表达的研究

目的探讨犬尿道瘢痕组织中转化生长困子β1（TGF-β）和基质金属蛋白酶-1（MMP1）的表达及其意义。方法选取12只健康雄性成年犬,采用小儿电切镜制作犬尿道狭窄动物模型,应用免疫组织化学方法检测犬尿道狭窄段瘢痕组织中TGF-β1和MMP-1的表达,以实验组犬尿道狭窄远端2cm处正常尿道组织作为对照组。结果TGF-β1在实验组犬尿道瘢痕组织与对照组的阳性表达率分别为100．00％与18．18％,两者差异具有统计学意义（P〈0．05）;MMP-1在实验组犬尿道瘢痕组织与对照组的阳性表达率分别为63．64％与9．09％,两者差异具有统计学意义（P〈0．05）。结论TGF-β1和MMP-1与犬尿道瘢痕形成关系密切。     

Tissue-engineered buccal mucosa using silk fibroin matrices for urethral reconstruction in a canine model

Background

To investigate the feasibility of urethral reconstruction using tissue-engineered buccal mucosa (TEBM) with silk fibroin (SF) matrices in a canine model.

Materials and methods

Autologous oral keratinocytes and autologous fibroblasts were isolated, expanded, and seeded onto SF matrices to obtain TEBM. The TEBM was assessed using hematoxylin and eosin staining and scanning electron microscopy. A 5-cm urethral mucosal defect was created in 10 female canines. Urethroplasty was performed using TEBM in five canines in the experimental group and with SF matrices without cells in the five canines in the comparison group. Retrograde urethrography was performed after 6 mo of grafting. The urethral grafts were analyzed grossly and histologically.

Results

The oral keratinocytes and fibroblasts exhibited good biocompatibility with the SF matrices. TEBM could be constructed using SF matrices. The canines implanted with the tissue-engineered mucosa voided without difficulty. The retrograde urethrography revealed no sign of stricture. The histologic staining showed that epithelial cells developed gradually and exhibited stratified epithelial layers at 6 mo. In the comparison group, the canines had difficulty voiding, and the retrograde urethrography showed urethra stricture. The histologic staining showed that one to two layers of epithelial cells developed.

Conclusions

The TEBM using SF matrices could be a potential material for urethra reconstruction.     

New device for visual neodymium:YAG laser prostate ablation: Acute and chronic canine evaluation

This canine study (n = 6) evaluated the acute and chronic effects of Nd:YAG laser prostatectomy using a Prolase II fiber. The Prolase II device consists of a 1,000 μm quartz fiber which directs a cone of Nd:YAG laser energy, at 45° to the axis of the fiber, into the prostatic urethra under direct visual guidance [visual laser ablation of prostate, (VLAP)]. Under visual guidance and saline irrigation, 60 seconds of 60 watts of laser power was delivered at 3, 6, 9, and 12 o'clock positions (14,400 J). One canine was instrumented but received no laser energy (control). One prostate was harvested acutely. The remaining four laser-treated dogs were evaluated at 6 to 16 weeks. The histopathology of acute laser effects shows areas of necrosis with loss of glandular structures and stromal edema. Surrounding this area was a zone of degenerative glandular structures extending up to 12.6 mm into the prostate. Two of the four dogs developed urinary retention at 6.5 and 9 weeks. On examination, both were found to have fibrotic strictures at the distal prostatic urethra with markedly dilated proximal prostatic urethral lumens (1.98 and 2.8 cm). Two other dogs showed no signs of urinary retention at sacrifice. Histopathology, both the 6 and 16 week laser-treated animals without urinary retention demonstrated dilated prostatic urethras with maximum cross-sectional diameters of 1.52 and 1.50 cm, respectively. However, the 16 week dog demonstrated mild distal urethral narrowing by urethrogram. The control dog demonstrated normal histology of the prostate at 16 weeks. This study demonstrates the safety and initial results of a delivery device for trans-urethral laser prostate ablation in a canine model. Further studies are needed to evaluate the cause of the fibrotic urethral strictures in this model and determine its clinical relevance. © 1994 Wiley-Liss, Inc.     

腔内钬激光联合等离子治疗尿道狭窄的临床分析（附128例分析）

目的：探讨联合使用输尿管镜腔内钬激光及等离子双极电切治疗尿道狭窄的临床疗效及安全性。方法：对128例尿道狭窄患者（其中合并膀胱结石88例）采用输尿管镜行钬激光尿道狭窄内切开联合等离子双极电切,并在等离子电切镜鞘下使用钬激光碎石治疗,术后查B超、X线片及最大尿流率（Qmax）观察疗效。结果：128例患者均一次手术成功,无结石残留,手术时间15～92min,平均42min,留置尿管4～6周,拔除尿管后排尿通畅并定期尿道扩张。术后3个月Qmax较术前明显改善。结论：采用腔内钬激光联合等离子双极电切治疗尿道狭窄具有创伤小、并发症少优点,并能同时治疗膀胱结石,是安全有效的治疗方法。     

Incidence of urethral stricture after transurethral resection of prostate Effects of urinary infection, urethral flora, and catheter material and size

Urethral stricture is the most common complication of transurethral resection of prostate, occurring in up to 29 per cent of cases. A prospective trial was initiated to ascertain if the presence of positive urine and urethral bacterial cultures made any significant difference in urethral stricture incidence. One hundred patients were entered in the trial, 50 receiving latex catheters and 50 receiving Teflon catheters. There was no significant difference between the two groups in incidence of urethral stricture, and there was no correlation between positive urine and urethral bacterial cultures and stricture formation. It is suggested, therefore, that urethral catheter material and size and the presence of organisms in the urine and in the urethra do not contribute significantly to the formation of urethral stricture following transurethral resection of the prostate.     

Radical surgery with pubectomy for primary male posterior urethral cancer--a case report]

A 38-year-old male patient with the past history of polioencephalopathy was admitted with urinary retention and high grade fever. Although he was able to walk he had the intelligence of a 3-year-old child and his spine, thorax, fingers were deformed remarkably. Immediately after the admission, cystostomy was carried out and 600 ml of stinky and cloudy urine was noted. Although intensive antibiotic therapy was performed, high grade fever with leucocytosis (greater than 15,000/mm2) persisted for more than 10 days. Retrograde urethrogram showed stricture in the anterior urethra as well as irregular filling defect in the bulbomembranous urethra. After urethral dilation using urethral dilators, 18Fr nephrostomy balloon catheter was indwelled and the patient was discharged. However, the urethral irregular filling defect was unchanged and cytological examination of urine and urethral secretions revealed class V. After the readmission, endoscopic examination revealed papillary tumor lesions occupying the whole posterior urethra were found. With the diagnosis of invasive posterior urethral cancer, anterior exenteration by en bloc pubectomy, pelvic lymphadenectomy and ileal conduit urinary diversion were carried out. On the surgical specimen, the tumor occupied the bulbomembranous and prostatic urethra. Histopathological diagnosis was TCC G3 greater than SCC, stage B. Since the tumor invaded the serosa of the membranous urethra, we thought it could not be removed completely without the pubctomy.     

Photodynamic therapy: response of normal canine urethra using a cylindrical fiber

Normal urethral response to photodynamic therapy (PDT) utilizing a cylindrical fiber was assessed in ten study and two control NIH fox-hounds. The canine urethras were treated 48 hours after intravenous injection of 3 mg/kg dihematoporphyrin ether (Photofrin II). A 1-mm fused silica optical fiber, with the distal 2-3 cm modified for cylindrical light distribution (660-microns diameter), was placed in the pendulous urethra. An argon-pumped dye laser delivered 100 mW of 630-nm light for 7 minutes (42 J) to the treatment area. Urethroscopy using either a 2.5-mm or a 2.8-mm flexible pediatric bronchoscope with video recording capability was performed immediately after PDT (12 animals) and 6 weeks later (nine animals); intravenous urography was performed 3 days and 6 weeks after PDT. There was no evidence of either urethral damage or stricture formation in any animal. Histopathology of the first three study specimens, obtained at 6 weeks, confirmed the absence of any pathology. Flexible instrumentation facilitates post-treatment assessment. This study demonstrates for the first time that, when a cylindrical fiber is used, photodynamic therapy may be applied to the urethra without damage to the normal urethral mucosa. This result has implications for potential treatment of initial or recurrent carcinoma in situ of the urethra using PDT.     

Healing response of the canine prostate to Nd:YAG laser radiation

The objective of the study was to characterize the healing response of the canine prostate to laser thermal injury. The study included 20 canine prostates that underwent transurethral laser radiation. The prostates were retrieved 1 hr after laser radiation in 7 dogs (acute group), and from 3 days to 9 weeks in 13 dogs (chronic group). Two distinct features were observed. First, reepithelialization of the prostatic urethra resulted from mobilization of proliferating epithelial cells from acinar and ductal prostatic epithelium into the cavity surface, and not from the edges of the wound at the bladder neck. Squamous cell metaplasia was a prominent feature of reepithelialization. Second, the healing process in the canine prostate was relatively unimpeded. The large glandular component provided abundant germinal epithelial growth, and the absence of stromal elements allowed for complete sloughing of necrotic tissue without residual eschars. Further, the lesions in the chronic group had a tendency to be larger that those in the acute group, suggesting that extended delayed necrosis may occur at deep prostatic tissue layers. © 1996 Wiley-Liss, Inc.     

Endourological re-establishment by transluminal puncture for a complete obliteration of traumatic urethral disruption

We performed transluminal re-canalization by needle puncture under fluoro-endoscopic control on a total of ten patients (membranous urethra, 8; bulbous urethra, 2) with complete obliteration after traumatic urethral disruption. The re-canalized tract was created by balloon dilation, internal urethrotomy or endoscopic resection of the scar tissue. The patient age ranged from 10 to 57 years (mean age; 37.9 +/- 15.3 years). A transluminal puncture was attempted in three patients by transperineal-transurethral approach and in seven by transurethral approach. In one of them, who sustained a complete membranous disruption 5 weeks ago, transluminal puncture failed because of the movable proximal urethra. The remaining nine patients voided without difficulty for the mean follow-up period of 18.1 +/- 14.3 months (range: 2-46). Three patients had mild stress urinary incontinence. A transluminal puncture is less invasive, safe and reliable for re-establishment of the true proximal part of the disrupted urethra. It can be recommended as a useful technique for endo-urological re-establishment for a completely obliterated urethra. Although this endoscopic re-establishment requires urethral sounding or internal urethrotomy for 6 months postoperatively, it may be an alternative to conventional surgical repair.     

Antegrade cystoscopic light source guided laser urethrotomy for the treatment of completely obliterated urethra

ObjectiveA urethral stricture is the narrowing of the urethra caused by scar formation. The etiologies include infection, trauma with total urethral disruption, and iatrogenic procedures. The impact of urethral stricture diseases is very high. Several kinds of endoscopic procedures have become available for managing the disease. Among them, complete obliteration of the urethra during endoscopic procedures remains a challenge for surgeons. We describe a modified procedure in which laser urethrotomy was guided under the light source from an antegrade flexible cystoscope for treating a short completely obliterated urethra. This procedure is indicated if the obliterated segment is less than 10 mm because longer strictures may increase the chance of extra false lumen formation and bleeding.Materials and MethodsForty-three male patients who underwent optical urethrotomy for urethral strictures at Kaohsiung Municipal Ta-Tung Hospital (Kaohsiung, Taiwan) between March 2013 and January 2015 were induced in the study. Five of these patients were diagnosed as having complete urethral obliteration.ResultsIn all five patients with a completely obliterated urethra, retrograde laser incision was performed successfully. Three patients had total bulbar urethral obstruction and two had penile obstruction. All patients experienced improved urination after the procedure.ConclusionOur preliminary data showed that our modified method for treating a completely obliterated urethra yielded satisfactory results. Long-term follow-up and large-scale studies should be conducted to better examine technique efficacy; however, our current results regarding the simple modification of endoscopic urethrotomy seem promising.     

经会阴四维超声在女性压力性尿失禁诊断中的初步应用

目的探讨经会阴四维超声在女性压力性尿失禁（SUI）患者中的应用价值。方法应用经会阴四维超声技术,观察22例女性压力性尿失禁患者在静息和Valsalva动作（屏气并向下用力至最大腹压）两种状态下四维超声图像的变化,并分析平静呼吸状态下的尿道长度、膀胱逼尿肌厚度（DWT）;最大Valsalva动作后的膀胱颈移动度（BND）、尿道内口漏斗有无形成等指标。以26例正常女性作为对照。结果静息时,SUI组与对照组尿道长度及DWT比较,无统计学差异（P〉0．05）;最大Valsalva动作时,SUI组的膀胱颈移动度明显大于对照组,尿道内口漏斗形成率也明显高于对照组（P〈0．05）。结论经会阴四维超声可用于评估女性压力性尿失禁患者的盆底解剖和功能,值得临床推广应用。     

经尿道前列腺切除术后再手术原因分析

目的 探讨经尿道前列腺切除术后再手术的原因.方法 回顾分析202例经尿道前列腺切除术的临床资料,其中再手术16例中,继发出血7例、尿道狭窄6例和前列腺癌3例,分析原因及处理对策.结果 术后出血可能有腺体残留、切面不光整、前列腺创面感染、膀胱痉挛、电凝创造面焦痂脱落等引起.尿道狭窄和膀胱颈挛缩可能与术中切断膀胱颈口环形肌肉、电凝时功率过大、气囊管牵拉过度或时间过长有关.导尿管过粗,留置时间过长,拉力过大,对尿道产生压迫作用,引起尿道黏膜缺血坏死致尿道狭窄.术前常规行血清PSA检查,排除前列腺癌,术后应即行薄层病理切片检查,以尽早发现隐藏的前列腺癌.16例再手术与腺体残留、感染、膀胱颈部挛缩和导尿管压迫留置时间过长等因素有关,再次手术治愈.结论 围手术期处理和熟练掌握手术操作技术是防止经尿道前列腺切除术后再手术的关键.     

Changes in bladder neck geometry and closure pressure after midurethral anchoring suggest a musculoelastic mechanism activates closure.

AIMS: The aim of this study was to investigate the anatomical origins and clinical significance of cough pressure transmission ratio (CTR) by using virtual-operation (VO) techniques. METHODS: Thirty-four patients underwent perineal ultrasound examination, standard urethral pressure cough testing both with and without unilateral midurethral anchoring (VO), all tests being performed without urethral elevation. In eight patients where there was no change in CTR, a one-sided fold of suburethral vagina (VO) was taken (pinch test) and the CTR repeated. RESULTS: After midurethral anchoring, maximal urethral pressure increased from a mean of 33.25 cm H2O to a mean of 58.06 cm H2O (P < 0.0001) and restoration of anatomy was noted in all 11 patients who had obvious funneling on straining. Conversion of a <100% CTR to >100% CTR in the proximal urethra was observed in 14 of 22 patients (P < 0.005), with no significant change noted in the distal urethra. Further conversion of CTR was noted in six of the remaining eight patients with unilateral plication of suburethral vagina (pinch test). CONCLUSIONS: A musculoelastic closure mechanism most likely activates urethral closure. CTR is most likely an index of changed intraurethral area, not necessarily closure, and may be a more sensitive objective test than perineal ultrasound for diagnosing urethral narrowing, especially when used with virtual-operation techniques.     

Colour Doppler ultrasonographic location of the bulbourethral artery, and its impact on surgical outcome

OBJECTIVE: To assess the location of bulbourethral arteries in men with a 'normal' urethra and to study anatomical alterations in men with urethral stricture. PATIENTS AND METHODS: A linear-array transducer was used on the ventral surface of the penis to study the urethra. Fifteen men with a normal urethra and 15 with a stricture of the bulbar urethra were assessed. After conventional grey-scale imaging to evaluate the extent of disease, the urethral artery in the bulbar urethra was located by colour Doppler ultrasonography. RESULTS: The site of the urethral arteries in 'normal' men varied among individuals; they were at the 10-2 o'clock position in six men, 8-10 o'clock and 2-4 o'clock in six, and at the 4-8 o'clock position in three. In normal men the symmetry of arteries was maintained and the mean distance from the lumen was 2.67 mm. In men with urethral stricture, there was a loss of symmetry in all cases. In a dense stricture the urethral arteries could not be detected on either side in three of cases, while only a single artery was seen in three. In two men, both the arteries were on one side. The mean distance of the urethral artery from the lumen of urethra was 1.88 mm. CONCLUSIONS: Contrary to the popular belief that the urethral arteries are located at the 3 and 9 o'clock position, we found that there was no predictable pattern for their anatomy. These observations might have implications for treating urethral stricture disease with visual internal urethrotomy, as they could help to avoid injury to the bulbourethral artery.