1. Female urethral diverticulae with calculi

2. Introduction :  Diverticula of the female urethra are rare lesions occurring predominantly in the distal two thirds of the urethra.  They are thought to be derived from the periurethral glands as a result of recurrent infections. Urethral diverticula (UD) have historically been described with the classic triad of three D's e.g. Dysuria, Dysparunia, and Dribbling, which are present only in about one third of cases.  They can be asymptomatic and incidentally detected or may present with symptoms like painful vaginal mass, chronic pelvic pain, refractory lower urinary tract symptoms, and recurrent urinary tract infections (UTI).

3.  Because of the varied symptomatology, they pose a challenge to the treating clinician. They predominantly affect females in third to fifth decade of life with overall incidence of 1-6%.  Complications of urethral diverticulum include recurrent infection, urinary incontinence, calculus formation, and development of intradiverticular neoplasms (3).  Urinary stasis causes recurrent UTIs and this is a frequent presenting feature occurring in about one-third of patients (6).  Stagnant urine, salt deposition and urothelial mucus also predispose to calculus formation in 1.5–10% of urethral diverticula(5).  Inflammation and chronic irritation within the urethraldiverticulum may lead to malignant transformation including adenocarcinoma (1– 4), transitional cell carcinoma or squamous cell carcinoma.

4. Case report:  A 35-year-old female presented to emergency with abdominal pain and urinary retention since 8 h.  She complained of repeated abdominal pain since 6 months and stress incontinence since 15 days.  She had history of similar episode 2 months back for which she was catheterized for 1 week. She also complained of frequency, poor stream, straining, incomplete voiding, and dysuria for 6 months.  There was no history of hematuria, flank pain, and menstrual disturbances.  Urinary bladder was palpable on abdominal examination. She was catheterized and drained about 400 ml of urine.

5.  Routine blood picture and serum chemistries were within normal limits.  On abdominal ultrasonography no abnormality was detected, whereas on transvaginal sonography performed with high frequency 5- to 9- MHz tightly curved array probe revealed a hypoechoic cystic structure posterior to urinary bladder and urethra with enhanced through- transmission and multiple echogenic structure within it, possibly a stone.  Communication with the urethra could not be delineated.  A magnetic resonance imaging (MRI) of pelvis was done which showed a well-defined cystic structure posterior to urinary bladder measuring 1.6 x 1.2 cm, displacing the uterus superiorly and vagina and cervix posteriorly and seen communicating with urethral lumen.

6.  Trans-vaginal excision of diverticulum was done through an inverted U-shaped incision over the anterior vaginal wall.  Vaginal flaps were raised with careful preservation of the periurethral fascia and meticulous dissection of the diverticulum up to the neck.  Diverticulum was excised and repair was done over 14F catheter in four layers, e.g. urethra, periurethral fascia, Martius flap, and vaginal tissue.  The urethral catheter was removed at 3 weeks, after voiding cystourethrogram (VCUG) revealed no extravasation. She is presently asymptomatic four months after surgery

7. Pelvis radiograph shows radiopaque calculi inferior to pubic rami.

8. Transvaginal sonography shows cystic structure with calculi.

9. Transvaginal sonography shows cystic lesion in periurethral region.

10. Transvaginal sonogram shows multiple echogenic foci in the cystic lesion – multiple calculi calculi

11. T2 weighted coronal image (T Repitition 4340, T Echo 117) shows hyperintense lesion with hypointense rim seen in right parasaggital region(arrow) adjacent to urethra, showing communication with urethre.

12. T2 weighted axial view shows horizontal hypointense rim(arrow) seen in posterior part of lesion suggestive of calculi.

13. Intraoperative image shows diverticulum in periurethral region diverticulum

14. Discussion:  Appropriate investigations play a vital role in the diagnosis of urethral diverticula and these investigations should provide the surgeon with information in relation to the location, number, size, configuration and communication of the urethral diverticulum.  The investigations should also be able to identify any associated malignancy or calculi.  Corresponding to the location of the periurethral glands, about 90% of UDs open posterolaterally in the middle or distal urethra.  Although usually single, globular, and small, UDs may be multiple, may attain various shapes and grow to large sizes.  In our patient, it was seen in periurethral region in anterior urethra.

15.  Strong clinical suspicion based on history, with focussed physical examination and appropriate radiological investigations is vital for the diagnosis of UD. It should be differentiated from vaginal leiomyoma, Skene's gland cysts, and abscesses, Gartner's duct cysts. Investigations  Magnetic resonance imaging (MRI) is felt to be the most sensitive mode of imaging for the diagnosis of urethral diverticulum (1).  MRI offers higher resolution, providing detailed information regarding number, location, size, configuration, complications, and communication with the urethra of diverticula.  In addition it has the ability to differentiate urethral pathology from anatomical variants and identify the presence of stones or neoplasms (2). This modality of imaging therefore provides useful information for surgical planning.

16.  Voiding-Computed-Tomography (CT) urethrography and virtual urethroscopy are further-imaging techniques, that provide high diagnostic accuracy.  However, they may not always be available (3), (4). If such imaging is not available, ultrasound is an alternative choice. (2)  The entire length of the urethra and surrounding tissues can be visualised in the absence of ionizing radiation, it can provide detailed information regarding the diverticulum and identify differential diagnoses.  Voiding cystourethrogram and retrograde positive pressure urethrography rely on contrast medium entering the lumen of the diverticulum therefore they are only effective if the opening is sufficiently patent. Hence they have a low sensitivity.

17. Management  Patients with mild symptoms can be managed conservatively. This usually involves prophylactic antibiotics and monitoring. Digital decompression post voiding, periodic needle aspiration and urethral dilation has also been suggested.  Surgery is the mainstay of treatment for UD and surgical excision and urethral reconstruction remains the most popular modality.  The common surgical treatment for urethral diverticulum is transvaginal diverticulectomy though selected patients may be managed by transurethral or open marsupialisation.  Total excision of the diverticulum, preservation of periurethral fascia, and watertight and tension-free closure with non-overlapping suture lines are vital for optimal surgical outcome.  Simultaneous anti-incontinence surgery may be done in patients with symptomatic stress urinary incontinence

18. Conclussion:  Urethral diverticula are more common than is currently being diagnosed. This delay in diagnosis can have a significant impact on a patient’s outcome.  Risk factors for the development of postoperative complications are delayed diagnosis (>12 months), size (>4 cm) and complex configuration (e.g. horseshoe) (4).  Large and complex diverticula increase the difficulty of the dissection and subsequent reconstruction.  Patients with a delayed diagnosis (over 12 months) have been found to be at high risk of developing postoperative complications.

19.  More worryingly, high recurrence rate after surgery and early metastases is the unfortunate outcome of delayed diagnosis of diverticular neoplasms (6), (7).  Therefore, by being more aware of urethral diverticulum as a differential diagnosis, clinicians may be able to reduce this delay and the complications that can occur with the condition.  Because female urethral diverticulum is becoming more prevalent, radiologists should be aware of its imaging features and the various imaging techniques that are optimal for its evaluation.  Modern imaging techniques, including US, MR imaging, voiding CT urethrography, and virtualurethroscopy, can help precisely identify a female urethral diverticulum, locate its orifice, and differentiate it from other paraurethral pathologic conditions.

20. References: 1. Antosh D D, Gutman R E. Diagnosis and management of female urethral diverticulum. Female Pelvis Med Reconstr Surg. 2011; 17(6): 264 – 27. 2. Dwarkasing R S, Dinkelaar W, Hop W C, Steensma A B, Dohle G R, Krestin G P. MRI evaluation of urethral divercula and differential diagnosis in symptomatic women. AJR Am J Roentgenol. 2011; 197(3): 676 – 682. 3. Smith N A. Treatment approach to female urethral diverticulu m. Rev Col Bras Cir.2011; 38(6): 440 – 443. 4. Rovner ES. Urethral Diverticula. In: Raz S, Rodriguez L, editors. Female Urology.3red. Philadelphia:Saunders; 2008. p. 815-34. 5. Ljungquist L, Peeker R, Fall M. Female urethral diverticulum: 26- year follow-up of a large series. J Urol. 2007; 177(1): 219 – 224. 6. Lee J W, Fynes M M. Female urethral diverticula. Best Pract Res Clin Obstet Gynaecol. 2005; 19(6): 875 – 893. 7. Bradley C S, Rovner E S. Urodynamically defined stress incontinence and bladder outlet obstruction coexist in women. J Urol 2004; 171: 757 – 760.