Introducton
Repair of urethral diverticulum was first described as early as the 19th century but the modern era in the diagnosis and treatment of female urethral diverticula (UD) began in 1956 with the advent of positive pressure urethrography by Davis and Cian ( , ). The development of ultrasound and MRI has subsequently greatly improved the diagnostic tools for physicians. The true prevalence of female UD is not known; however, it is reported to occur in up to 1%–6% of adult females in some series ( ). It is generally believed that adult UD are formed as a result of infection of obstructed periurethral glands. This infection leads to abscess formation and eventual rupture into the urethral lumen, resulting in an epithelialized cavity in communication with the urethra ( ). Once the diagnosis is confirmed, definitive therapy consists of operative excision and reconstruction.
Diagnosis
Signs and Symptoms
Although presentation is highly variable, the most common symptoms are irritative lower urinary tract symptoms, pain, and infection ( , , ). Urethral diverticula may be found during the evaluation of recurrent UTIs, or lower urinary tract symptoms including those attributed to overactive bladder. The classic presentation of the “3 D’s”: dyspareunia, dysuria, and postvoid dribbling appear to be less common than previously reported ( , , ). Moreover, up to 20% of patients lack symptoms, with the UD being an incidental finding.
Physical Examination
The differentiation between anterior vaginal wall lesions sometimes cannot be made on the basis of a physical examination alone and may require additional radiologic imaging. A particularly hard anterior vaginal wall mass may indicate a calculus or cancer within the UD and mandates further investigation. During physical examination, the urethra may be gently “milked” distally in an attempt to express the contents from the UD cavity.
Radiologic and Cystoscopic Evaluation
Currently available techniques for the evaluation of UD include voiding cystourethrography (VCUG), ultrasound (US), and magnetic resonance imaging (MRI) ( Fig. 86.1 ). Urodynamic studies, especially videourodynamics, are used in patients with urinary incontinence or significant voiding dysfunction in order to more objectively characterize these symptoms, especially if surgery is planned. Videourodynamics may be particularly helpful in differentiating postvoid dribbling from true stress urinary incontinence as well as characterizing associated urinary incontinence in those considering concomitant antiincontinence surgical therapy. The success in identifying adiverticular ostia on cystourethroscopy is highly variable and is reported to be between 15% and 89% ( , , ).
Indications for Surgery
The indications for surgical repair of urethral diverticula include refractory genitourinary symptoms such as recurrent UTI, dyspareunia, dysuria and others attributable to the lesion. Very little is known regarding the natural history of untreated urethral diverticula. Patients who are not surgical candidates or do not desire surgical repair should be counseled that there are reports of carcinomas arising in UD which may not be diagnosed if surgery is not undertaken ( , ). Patients who pursue nonsurgical therapy should thus be counseled to have ongoing monitoring. Those with UD and symptomatic stress urinary incontinence (SUI) can be considered for a concomitant anti-incontinence procedure at the time of UD excision. However, a prophylactic fascial sling for those without preoperative SUI is not recommended ( ). Urodynamics may be helpful in certain situations in clarifying the type of urinary incontinence especially in those with mixed symptoms. Furthermore, videourodynamics may be helpful in distinguishing true SUI from postvoid dribbling due to residual urine in the diverticulum after voiding, which, in some individuals, may be misinterpreted as SUI.
Alternative Therapy
Patients electing nonoperative management can be treated with daily low-dose antibacterial preparations and digital stripping of the anterior vaginal wall following micturition to prevent postvoid dribbling and reduce the risk of UTI due to stasis in the UD.
Marsupialization (Spence-Duckett)
For patients with very distal urethral diverticula who don’t desire surgical reconstruction, a deep incision in the ventral urethra incorporating the anterior vaginal wall proximally into the diverticulum creates a “hypospadiac” meatus. This will marsupialize the urethral diverticulum into the vagina ( Fig. 86.2 ). However, an aggressive incision proximally risks stress urinary incontinence because the sphincteric mechanism may be injured.
In rare cases, when the UD is highly symptomatic, acutely infected, and unresponsive to antibiotic therapy, or in cases when a complete elective excision should be postponed such as during pregnancy, a transvaginal incision (diverticulotomy) can be performed directly into the UD cavity. This will create a temporary urethrovaginal fistula from the UD ostia through the UD cavity into the vagina, thus decompressing the UD. The UD and fistula are subsequently repaired at the time of planned elective excision and reconstruction.
Operative Technique
The principles of the urethral diverticulectomy operation have been well described ( Box 86.1 ) . There are only a few minor differences between surgeons, including the type of vaginal incision (inverted U vs inverted T), whether it is necessary to remove the entire mucosalized portion of the UD, and finally, the optimal type of postoperative catheter drainage (urethra only vs urethra and suprapubic catheter).
Mobilization of a well-vascularized anterior vaginal wall.
Preservation of periurethral fascia.
Identification and excision of the neck of UD or ostia.
Removal of the entire UD wall or sac (mucosa)
Watertight closure of the urethra
Multilayered, nonoverlapping closure with absorbable suture
Closure of dead space
Preservation or creation of continence
The patient is placed in the high lithotomy position with all pressure points well-padded, and standard vaginal antiseptic preparation is applied. The use of a headlight as well as operative magnification (1.5×–2.5× loupes) assists with the dissection and precise reconstruction. A Foley catheter (16F) is placed per urethra.
A weighted vaginal speculum and Scott retractor with hooks are placed to assist with exposure. An inverted U is marked out along the anterior vaginal wall proximal from the urethral meatus with the limbs extending to the bladder neck or beyond. The inverted U incision provides excellent exposure laterally at the level of the midvagina and can be extended proximally as needed for lesions that extend beyond the bladder neck. Normal saline can be injected along the lines of the incision beneath the vaginal wall to facilitate dissection. We prefer injectable saline over vasoconstrictive agents so as to allow for early recognition of bleeding vessels and avoid delayed hemorrhage. A posterolateral episiotomy may be of help in some patients with a narrow introitus.
An anterior vaginal wall flap is created by careful dissection in the potential space between the vaginal wall and the periurethral fascia ( Fig. 86.3 ). The use of sufficient countertraction during this portion of the procedure is important in maintaining the proper plane of dissection. Care should be practiced while dissecting to preserve the periurethral fascia, maintain an adequate blood supply to the anterior vaginal wall flap, and avoid inadvertent entry into the UD. Preservation and later reconstruction of the periruethral fascia is of paramount importance in order to prevent UD recurrence, close dead-space, and avoid urethrovaginal fistula formation postoperatively. Pseudodiverticula have been described where this layer of tissue is considerably attenuated or even absent ( ). In these patients, an interpositional flap, or graft such as an autologous pubovaginal sling, may be used for reconstruction.