Can magnetic resonance imaging differentiate among transurethral bulking agent, urethral diverticulum, and periurethral cyst?

Evaluation and management of urethral and periurethral masses in women

PURPOSE OF REVIEW

Female periurethral masses are an uncommon occurrence. The purpose of this review is to describe etiologies of female urethral and periurethral masses and to provide an update on diagnosis and management.

RECENT FINDINGS

The most common causes of periurethral and urethral masses in women are urethral caruncles, urethral diverticula, and Skene's gland cysts. Urethral meatal lesions such as urethral caruncles and prolapse can be managed conservatively with topical estrogen therapy and close follow-up or should be excised in the setting of thrombosis, significant or recurrent bleeding, acute urinary retention, or persistent pain. Benign periurethral gland masses, such as Skene's gland cysts, Gartner's duct cysts, and Mullerian duct cysts, remain rare. Recent case series reveal a high rate of surgical management of these lesions with few complications. Urethral malignancy or malignant transformation of benign etiologies are even rarer but can be aggressive in nature and should be treated promptly.

SUMMARY

Nonspecific urinary and vaginal symptoms as well as similar physical presentations make diagnosis of urethral and periurethral lesions in females difficult. Magnetic resonance imaging is useful for differentiation of periurethral masses. The decision for conservative or surgical management is typically guided by patient symptom bother, as well as concern for urethral malignancy.

A diagnostic conundrum: Is it a periurethral diverticulum/cyst or a bulking agent (Bulkamid)?

INTRODUCTION

Urethral bulking agents are commonly used to manage female stress urinary incontinence (SUI) as they have been suggested to be safe, efficacious, and a minimally invasive surgical option. Bulkamid is a newer bulking agent that has been introduced and promoted in the market for use. It is non-particulate in nature with high tissue biocompatibility, and consequently, it is difficult to differentiate between Bulkamid and a periurethral cyst on magnetic resonance imaging (MRI). This, therefore, presents a diagnostic dilemma.

METHODS AND MATERIALS

Here we describe two cases with previous injections of Bulkamid referred to our Centre for management of a presumed periurethral diverticulum based on MRI findings. Both patients were reviewed and examined in outpatient clinics with MRI findings discussed at MDT, further imaging was required.

RESULTS

We found that a limited noncontrast computed tomography (CT) pelvis, followed by a voiding cystometrogram (VCMG), and then a repeat limited noncontrast CT pelvis effectively differentiated between Bulkamid and these presumed periurethral diverticulae. The theory behind this was that during micturition, the contrast would pass through to the urethral diverticulum and appear as high-density (bright) material within the periurethral region (the pre-VCMG was required to prove that any high-density material was due to the contrast and not pre-existing high-contrast material).

CONCLUSION

A CT scan done in conjunction with a VCMG is likely to be more effective in differentiating between Bulkamid and a true periurethral diverticulum than an MRI scan. Appropriate diagnostic evaluation of periurethral lesions can lead to time-saving and cost-effective patient management as this will bypass the need for unnecessary investigations and possible unwarranted surgical intervention.

Foreign body granuloma development after calcium hydroxylapatite injection for stress urinary incontinence: A literature review and case report

Objectives

To present a case of foreign body granuloma (FBG) development after injection of calcium hydroxylapatite as a urethral bulking agent and to review all documented cases of this phenomenon in the literature.

Methods

We analyzed a new case of calcium hydroxylapatite-induced FBG. We also conducted a literature review of the PubMed, Embase, CINAHL, and Web of Science databases through March 2022. Reports were included if they contained stress urinary incontinence patients that developed an FBG after calcium hydroxylapatite injection. The cases were reviewed for presenting symptoms, patient demographics, granuloma details, and surgical treatment.

Results

We screened 250 articles and included six articles between 2006 and 2015 in addition to the present case. The median age of the patients was 65.5 years (range 45-93), and all patients were female. The most common presenting symptoms and the proportion of patients affected were difficulty voiding (4/8), recurrent urinary incontinence (3/8), and dyspareunia (2/8). The median time between the first CaHA injection and discovery of the FBG was 5 months (range 1-50). The median longest dimension of the FBGs was 1.85 cm (range 1.0-3.0). The 8 masses observed were evenly distributed throughout the urethra, with 3 in the bladder neck, 2 in the midurethra, and 3 in the distal urethra. Surgical excision was the predominant management choice, with some variation in technique.

Conclusions

Severe, persistent lower urinary tract symptoms after calcium hydroxylapatite injection may indicate an FBG, which has been successfully managed with surgical excision.

Urethral Masses

Urethral and periurethral masses in women include both benign and malignant entities that can be difficult to clinically differentiate. Primary urethral carcinoma is rare and the optimal treatment modality may vary depending on the stage at presentation. Because cancer-free survival is poor, clinicians shouldhave a high index of suspicion when evaluating a urethral mass. Some benign-appearing urethral masses may be safely observed. Surgical resection is an effective option that should be used based on patient preference and symptoms, and for suspicious lesions.