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A urethrotomy is an operation which involves incision of the urethra, especially for relief of a stricture. It is most often performed in the outpatient setting, with the patient (usually) being discharged from the hospital or surgery center within six hours from the procedure's inception. Urethrotomy (often referred to as DVIU, or Direct Visual Internal Urethrotomy) is a popular treatment for male urethral strictures. However, the performance characteristics are poor. Success is less than 9% for the first or subsequent urethrotomies. Most patients will be expected to experience failure with longer followup and the expected long-term success rate from any urethrotomy approach is 0%. Beginning in 2003, several urology residency programs in the northeastern section of the United States began advocating the use of urethrotomy as initial treatment in the young stricture patient, versus urethral dilatation. It is theorized that the one-to-two years of relief from stricture disease will allow the practitioner and the patient to plan the most effective treatment regimen without having the concern that undergoing multiple dilitations cloud the judgment of the patient. Furthermore, should urethroplasty be selected by the patient, minimal scar tissue will have developed at the site of the stricture in the urethrotomy patient, as opposed to the patient who had undergone the more conventional (dilitation) route. ==The procedure== Now the diagnosis has been confirmed by either cystoscopy or a prior urethrography, the patient is placed in the lithotomy position, and the urinary meatus is cleansed with an appropriate surgical cleansing agent (scrub), usually containing Povidone-iodine, then surgically draped. An IV antibiotic or other anti-infective medication is administered in conjunction with intravenous normal saline, and allowed to run until administration of the prescribed dose is completed. Most often, procedural sedation will be the chosen adjunct to patient comfort, and the patient will have received intravenous anxiolytic medication at sometime prior to, or during the surgical preparation. This medication is usually a benzodiazepine, often, diazepam or midazolam is employed. The urological surgeon or anesthesia practitioner may also choose to administer a narcotic analgesic such as fentanyl citrate, depending on the level of discomfort anticipated by the surgeon. In some cases, usually where longer strictures are present, a rapidly metabolized hypnotic agent such as propofol may be selected, as this allows for the immediate induction of short-term general anesthesia (note:endotracheal intubation will also be necessary if general anesthesia is administered). Constant monitoring of vital signs including pulse oximetry, cardiac monitoring (ECG), body temperature and blood pressure are carried out by the anesthesia practitioner until the patient is discharged post-operatively to the post-surgical recovery unit. A topical anesthetic, usually viscous lidocaine is instilled into the urethra, and a penile (crown) clamp is applied for at least five minutes, then removed immediately prior to the insertion of a cystoscope equipped with a transurethral injection system containing a local anesthetic (most often 2% (plain) lidocaine, or 0.5% (plain) bupivicaine). The urological surgeon will inject the anesthetic at the twelve o'clock, four o'clock, and eight o'clock positions at the face of the stricture using infiltrative technique, and ensuring that the entire length of the stricture has been medicated. The cystoscope (and injection system) will be withdrawn, and sufficient time will be allowed for the local anesthetic to take effect (usually five-to-ten minutes).〔 At this time a rigid urethrotome or a flexible cystoscope/urethrotome combination will be inserted and guided to the face of the stricture and a small blade towards the tip of the instrument will be deployed using a trigger mechanism to cut the stricture at locations determined by the surgeon. Upon completion of the internal incision(s), the instrument is withdrawn and an appropriately sized Foley catheter will be inserted through the repair and into the urinary bladder, and locked into place by filling its balloon (positioned inside of the bladder near the urethral junction) with sterile water. The Foley catheter serves two purposes, first, it provides drainage of the urine produced in the kidneys, and secondly, it secures the incised areas, holding them open for three to seven days to permit thorough healing of the urethra. The catheter is then attached to a urinary catheter drainage system (large bag or leg bag) via clear polypropylene tubing.〔(【引用サイトリンク】 publisher =PMPH - USA )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「urethrotomy」の詳細全文を読む スポンサード リンク
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