Ureterovaginal fistulas can be present in up to 12% of patients presenting with vesicovaginal fistulas cheap vytorin cholesterol test pin prick. Partial ureteral obstruction in a patient with a suspected fistula is suggestive of an ureterovaginal fistula until proven otherwise  cheap vytorin 30 mg mastercard cholesterol definition for biology. If ureteral stents cannot be passed beyond the site of obstruction purchase vytorin 30 mg with visa cholesterol hdl ratio low, a percutaneous nephrostomy tube should be placed to maximally drain the urinary system prior to operative repair. An antegrade nephrostogram can be performed to evaluate the remaining upper tract for other injuries, malignancy, and congenital anomalies. As described by Tancer, the uterus is filled with dye, and cystoscopy is performed to evaluate for the presence of dye and identify the fistulous tract, if present . Hysterography and cystography have been used successfully to identify vesicoureterine fistulas . In one series, hysterography was 100% sensitive in patients with suspected vesicouterine fistulas . Upper tract imaging should also be performed in conjunction with these imaging tests to rule out concomitant ureteral involvement (i. In the literature, the use of magnetic resonance imaging, transvaginal Doppler ultrasound, and hysterosalpingography for vesicouterine and vesicofallopian fistulas have been described [76,82]. These imaging modalities provide additional useful information in select patients; however, these tests are not usually necessary . Urodynamics Urodynamics is not considered a routine test in the urogenital fistula workup. Lower urinary tract symptoms, such as urinary frequency and urgency can coexist with urogenital fistulas. Urodynamics can identify the presence of detrusor overactivity and/or concomitant intrinsic sphincter deficiency. Similarly, bladder outlet obstruction can coexist with urethrovaginal fistulas due to scarring, stricture formation, bladder neck disruption, and/or the presence of foreign material (i. Urodynamics can also identify small capacity or poorly compliant bladders in patients with a history of pelvic irradiation and other risk factors for poor compliance , thereby identifying patients that may require a concomitant augmentation cystoplasty procedure  or alternatively require a urinary diversion [63,86]. Bladder capacity should be established in any patient who may require ureteral 1570 reimplantation, in the event a psoas hitch is needed . There are a variety of strategies that can be employed to allow adequate bladder filling during the test. First, vaginal packing can be placed at the beginning of the study, during catheter placement to slow the leakage of fluid per vagina. Second, the patient can be placed in the supine position, rather than sitting or standing. If these maneuvers fail, the clinician can attempt to place an 8 French Foley catheter through the large fistula tract. If the fistula is distal, the urodynamics catheter can be placed alongside a small urethrally placed Foley catheter. The Foley balloon will, in some cases, sufficiently obstruct the fistulous tract to allow bladder filling. Whether iatrogenic or obstetrical in origin, the clinician must maintain a high index of suspicion in any patient with continuous leakage of urine per vagina. A thorough history and physical examination will often identify the location and mechanism of fistula formation. Appropriate imaging and endoscopic evaluation can provide valuable information needed to determine the size, number, and location of the fistulous tract. Urodynamics can help establish baseline capacity, compliance, as well as bladder and urethral function if the fistula is small enough to occlude. A high index of suspicion is needed to ensure that all fistulous communications are identified, including those that communicate with nonuro- genital organs or structures. Epidemiological and surgical aspects of urogenital fistulae: A review of 25 years’ experience in southeast Nigeria. Observations on prevention and management of vesicovaginal fistula after total hysterectomy. Obstructed labor injury complex: Obstetric fistula formation and the multifaceted morbidity of maternal birth trauma in the developing world. Uretero-fallopian fistula after gynecological surgery for endometriosis: A case report. Uretero-fallopian tube fistula secondary to laparoscopic fulguration of pelvic endometriosis. Ten-year experience with transvaginal vesicovaginal fistula repair using tissue interposition. The incidence of urinary tract injury during hysterectomy: A prospective analysis based on universal cystoscopy. Lower urinary tract injury during gynecologic surgery and its detection by intraoperative cystoscopy. Vesicouterine fistulas following cesarean section: Report on a case, review and update of the literature. The risk of vesicovaginal and urethrovaginal fistula after hysterectomy performed in the English National Health Service—A retrospective cohort study examining patterns of care between 2000 and 2008. Impact of dose in outcome of irradiation alone in carcinoma of the uterine cervix: Analysis of two different methods. A quantified approach to the analysis and prevention of urinary complications in radiotherapeutic treatment of cancer of the cervix. Radiation therapy morbidity in carcinoma of the uterine cervix: Dosimetric and clinical correlation. Vesicovaginal fistula and mesh erosion after perigee (transobturator polypropylene mesh anterior repair). Efficacy and safety of using mesh or grafts in surgery for anterior and/or posterior vaginal wall prolapse: Systematic review and meta-analysis. Evaluation and treatment of iatrogenic ureteral injuries during obstetric and gynecologic operations for nonmalignant conditions. Acute renal failure and multiple fistulae formation related to an unusual vaginal foreign 1572 body. Vesicovaginal fistula caused by a vaginal foreign body in a 72-year-old woman: Case report and literature review. Combined vesicovaginal-ureterovaginal fistulas associated with a vaginal foreign body. Urethral injury associated with minimally invasive mid-urethral sling procedures for the treatment of stress urinary incontinence: A case series and systematic literature search. Simultaneous urethral erosion of tension-free vaginal tape and woven polyester pubovaginal sling. An uncommon case of urethrovaginal fistula resulting from tension-free vaginal tape. Delayed presentation of an enterocutaneous fistula after tension-free vaginal tape sling. Congenital vesicovaginal fistula with transverse vaginal septum presenting as menouria—A rare case report and brief review. Ureterouterine and vesicoureterovaginal fistulas as a complication of cesarean section.
Afferent and efferent communication in the bladder is facilitated by gap junction proteins buy vytorin australia cholesterol levels uk 5.3. Intradetrusor Interstitial Cells Interstitial cells are also found in the detrusor layer and shown to be spontaneously active  purchase vytorin pills in toronto cholesterol test healthy range. These cells stain for c-Kit and are located along both boundaries of muscle bundles in the guinea pig bladder 2 [34 generic vytorin 30mg on line low cholesterol foods.com,48,49]. They can increase Ca activity in response to cholinergic stimulation via M3 muscarinic receptor activation and can be spontaneously active. This suggests they could act as pacemakers or intermediaries in transmission of nerve signals to smooth muscle cells [48,50,51]. Hashitani and colleagues  suggested that interstitial cells in the detrusor may be more important for modulating 2 the transmission of Ca transients originating from smooth muscle cells rather than being the pacemaker 2 of spontaneous activity because Ca transients occur independently in smooth muscles and interstitial cells [34,49,52,53]. The accommodation of the bladder to increasing volumes of urine is primarily a passive phenomenon dependent on the viscoelastic characteristics of bladder wall and the quiescence of the parasympathetic efferent pathway [61–63]. Bladder distension–induced afferent activity triggers spinal reflex pathways, which facilitate storage by directly enhancing thoracolumbar sympathetic outflow and somatomotor discharge . Reflex activation of the sympathetic outflow inhibits any neurally mediated contractions of the bladder during filling phase of micturition [63,65,66]. Organization of this reflex response in the lumbosacral spinal cord is confirmed by its persistence even after transection of the spinal cord at the thoracic levels (Figure 23. However, this bladder to sympathetic mechanism to suppress detrusor contractions during urine storage may be weak in humans, given that bilateral retroperitoneal lymph node dissection (involves destruction of sympathetic chains) has no discernible alteration of filling or storage function in humans. During filling, sympathetic and somatic spinal reflexes are responsible for the low intravesical pressure and high urethral pressure maintained by the tonic activity of smooth and striated urethral sphincters, respectively  (Figure 23. The rise in intra-abdominal pressure during filling is also resisted by sympathetic and somatic spinal reflexes. The increased efferent firing in the pudendal nerve and the higher outlet resistance during filling are responsible for the maintenance of urinary continence and the increased activity of sphincter electromyogram during storage (Figure 23. The bladder afferent input during bladder filling activates pudendal motoneurons as a result of somatic spinal reflex (the guarding reflex) , whereas the motoneurons are reciprocally inhibited during voiding . This reflex may represent, in part, a continence mechanism that is activated by proprioceptive afferent input from the urethra or pelvic floor to induce closure of the urethral outlet. During the storage of urine, the distention of the bladder produces low-level bladder afferent firing. These responses occur by spinal reflex pathways and represent “guarding reflexes,” which promote continence. Sympathetic firing also inhibits detrusor muscle and transmission in intramural ganglia. The x-axis in all records represents bladder volume in milliliters, and the y-axis represents bladder pressure in centimeters of water and electrical activity of the electromyographic recording. On the left side of each trace, the arrows indicate the start of a slow infusion of fluid into the bladder (bladder filling). Vertical dashed lines indicate the start of sphincter 340 relaxation that precedes by a few seconds the bladder contraction in (a) and (b). In (b), note that a voluntary cessation of voiding (stop) is associated with an initial increase in sphincter electromyographic activity followed by a reciprocal relaxation of the bladder. A resumption of voiding is again associated with sphincter relaxation and a delayed increase in bladder pressure. The transition from storage phase to voiding phase can occur either involuntarily (reflexively) or voluntarily. The former is readily demonstrated in the human infant or in patients with neuropathic bladder when the bladder wall tension exceeds the micturition threshold due to increased urine volume. Voiding is initiated upon cessation of sympathetic and somatic input to the detrusor and sphincter, which causes sphincters to relax and the bladder neck to assume the shape of a funnel, and the concomitant increased parasympathetic activity causes the detrusor contraction to generate pressure for overcoming resistance generated by the collapsed urethra. At this point, increased afferent firing from tension receptors in the bladder reverses the pattern of efferent outflow, producing firing in the sacral parasympathetic pathways and inhibition of sympathetic and somatic pathways. Reversal in efferent outflow in both sympathetic and somatic innervations to the urethra and sphincter causes a reflex relaxation followed in a few seconds by parasympathetic nerve– mediated detrusor contraction (Figure 23. As a result, the pressure inside bladder rises and the urethral pressure falls, which is a prerequisite for the urine expulsion. Elimination of urine is also facilitated by noncholinergic/nonadrenergic nitric oxide release onto the internal urethral sphincter, resulting in a relaxation of the urethral outlet [69,70] and by removal of excitatory inputs to the urethra. Secondary reflexes elicited by flow of urine through the urethra also facilitate bladder emptying [61,66,71]. These reflexes require the integrative action of neuronal populations at various levels of the neuraxis (Figure 23. Complete bladder emptying is facilitated by urethra to bladder reflex occurring while urine is flowing through urethra as demonstrated in anesthetized cat experiments by Barrington [72,73] (Figure 23. The other component was activated by a visceral afferent pathway in the pelvic nerve to facilitate voiding at the spinal micturition center . Studies  in the anesthetized rat have further confirmed the seminal findings of Barrington . At the initiation of micturition, intense vesical afferent activity activates the brainstem micturition center, which inhibits the spinal guarding reflexes (sympathetic and pudendal outflow to the urethra). Measurements of reflex bladder contractions under isovolumetric conditions during continuous urethral perfusion (0. Desensitization of the urethral afferent with intraurethral capsaicin also dramatically altered the micturition reflex. The existence of this pudendal nerve–mediated reflex has been confirmed as low-frequency electrical stimulation of afferent axons in the human pudendal nerve and the deep perineal nerve, a caudal branch of the pudendal nerve in cats that can initiate reflex bladder contractions and voiding [75,76]. The existence of urethra to bladder reflex may explain why stress incontinence and urge incontinence are comorbidities in women. Women with mixed incontinence may have detrusor overactivity activated by leakage of urine into the urethra due to stress incontinence, which support the theory of stress incontinence inducing urge incontinence . Interestingly, surgical cure of the stress incontinence of women with mixed incontinence has resolved the urge incontinence in up to half of the patients. Inputs from supraspinal, spinal, and peripheral nervous system are necessary to maintain “switch-like” patterns of filling and voiding activity (Figures 23. The principal reflex components of these switching circuits are listed in Figures 23. Parasympathetic preganglionic axons that originate in the sacral spinal cord pass in the pelvic nerve to ganglion cells in the pelvic plexus and to distal ganglia in the organs. The pudendal and pelvic nerves also receive postganglionic axons from the caudal sympathetic chain ganglia. It is also possible that individual reflexes might be linked together in a serial manner to create complex feedback mechanisms. Thus, a bladder to sphincter to bladder reflex pathway could in theory contribute to the suppression of bladder activity during urine storage. Alterations in these primitive reflex mechanisms may contribute to neurogenic bladder dysfunction.
C. Grobock. Mount Olive College.