MR imaging of the male and female urethra

A diagnostic approach of various urethral diseases using multimodal imaging findings: comprehensive overview

In clinical practice, urethral diseases are not as frequent as conditions affecting other components of the urinary system. Radiological imaging tests, such as retrograde urethrography, CT, MRI, and PET/CT, along with patient history, are crucial for accurately assessing relatively rare urethral lesions. This article aimed to provide a comprehensive overview of urethral lesions, from traumatic changes to neoplasms, and discuss the multimodal imaging findings of various urethral lesions that radiologists should know. To this end, the normal imaging anatomy of the urethra and a step-by-step approach that can be used in clinical practice have been presented to help in the systematic understanding of urethral lesions.

Urethral length and its relationship with anthropometric parameters in adult male Nigerians

BACKGROUND

The available literature on urethral length in adult males is limited. To the best of our knowledge, such measurement has never been carried out amongst Nigerian and African men. This study aimed to document average urethral length as well as the relationship between urethral length and age, and anthropometric parameters amongst the Nigerian male adult population to add to the database for urethral length.

METHODS

It was a prospective cross-sectional study amongst adult male Nigerians who had an indication for urethral catheterization as part of their regular treatment at the urologic clinics as well as male adult patients who required urethral catheterization in the theatre and the wards for various reasons. All patients had anthropometric parameters measured or calculated. The total usable length (A) of the catheter was measured before catheterization and the unused catheter length (B) was measured after catheterization for each patient. The calculated urethral length (C) was obtained by subtracting B from A. Data were analyzed using SPSS version 26.0. Mean urethral length was determined while the correlation between urethral length and age as well as anthropometric parameters were determined using Pearson Correlation.

RESULTS

A total of 450 adult males were recruited. The mean age of subjects was 63.58 years with a range of 22-91 years. The average total usable and unused catheter lengths were 30.01 and 8.97 cm respectively. The mean urethral length among participants was 21.32 cm (8.4 Inches) with a range of 16.5 to 28 cm (6.5-11.0 Inches). There were no statistically significant correlations between urethral length and age ([r (450) = - 0.029, p = 0.546]) as well as with anthropometric parameters (height: r (450) = - 0.088, p = 0.61; weight: [r (450) = - 0.047, p = 0.324 and BMI: r (450) = - 0.082, p = 0.08) in adult males.

CONCLUSION

This study suggests that there may be racial differences in adult male urethral length but no relationship with age and anthropometric parameters. Further research is needed to explore these findings.

Malignant Neoplasms of the Penis with Radiologic and Pathologic Correlation

Penile malignancy is the third most common male-specific genitourinary malignancy, with squamous cell carcinoma representing the most common histologic type. Squamous cell carcinoma is an epithelial malignancy, frequently developing from the mucosal surfaces of the foreskin, glans, and coronal sulcus and manifesting as a distal infiltrative or ulcerated mass. This typically occurs in men from the 6th to 8th decades of life, and risk factors include human papillomavirus, phimosis, presence of foreskin and poor hygiene, chronic inflammatory conditions such as lichen sclerosus, trauma, and smoking. Primary urethral malignancies including urothelial carcinoma and adenocarcinoma can occur but may lack this distal predilection. Sarcoma, melanoma, leukemia or lymphoma, and metastatic disease are less common sources of penile malignancy. Because of the sensitive nature of penile malignancies, there may be delays in seeking care and in subsequent diagnosis. Recently, the staging guidelines for penile cancer have been updated concurrently with a shift toward more penile-preserving therapies, which have led to a larger role of imaging in diagnosis, staging, and treatment planning for penile malignancies. A variety of imaging modalities may play a role in the identification and staging of penile malignancy, including an increased use of MRI for local staging of tumors, CT and PET/CT for identification of nodal and distant disease, and US for image-guided biopsy. The authors discuss an imaging approach to a spectrum of penile malignancies, with an emphasis on radiologic and pathologic correlation and how knowledge of normal tissue types and anatomic structures can aid in the diagnosis and staging of these tumors. ^©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Urogenital sinus malformation: From development to management

Urogenital sinus (UGS) malformation, also known as persistent urogenital sinus (PUGS), is a rare congenital malformation of the urogenital system. It arises when the urethra and vaginal opening fail to form properly in the vulva and fuse incorrectly. PUGS can occur as an isolated abnormality or as part of a complex syndrome, and is frequently associated with congenital adrenal hyperplasia (CAH). The management of PUGS is not well-established, and there are no standardized guidelines on when to perform surgery or how to follow up with patients over the long term. In this review, we discuss the embryonic development, clinical evaluation, diagnosis, and management of PUGS. We also review case reports and research findings to explore best practices for surgery and follow-up care, in hopes of increasing awareness of PUGS and improving patient outcomes.

MRI Anatomical Investigation of Rabbit Bulbourethral Glands

Anatomical MRI is appropriate for the interpretation of soft tissue findings in the retroperitoneal part of the pelvic cavity. The aim of the current study was to use rabbits as an imaging model to optimize MRI protocols for the investigation of bulbourethral glands. The research was conducted on twelve clinically healthy, sexually mature male rabbits, eight months of age (New Zealand White), weighing 2.8 kg to 3.2 kg. Tunnel MRI equipment was used. The transverse MRI in the T2-weighted sequence obtained detailed images that were of higher anatomical contrast than those in T1-weighted sequences. The hyperintensity of the glandular findings at T2, compared to the adjacent soft tissues, was due to the content of secretory fluids. The quality of the anatomical tissue contrast has not shown much dependence on the choice of the sequence in dorsal MRI. The sagittal visualization of the rabbit bulbourethral glands corresponded to the localization of the research plane toward a median plane. The imaging results could be used as a morphological base for clinical practice and reproduction.

Imaging of the Bulbourethral (Cowper) Gland: Abnormalities and Differential Diagnosis

Normal Cowper glands and ducts are imperceptible at imaging. However, abnormalities of the Cowper glands and ducts are increasingly seen owing to increasing use of cross-sectional imaging. In this article, the authors present a comprehensive review of the normal anatomy of the Cowper glands and ducts and the clinical and imaging findings of conditions that affect them in an effort to help lead to appropriate diagnosis and management. A Cowper duct syringocele is a congenital or acquired dilatation of the Cowper duct in the bulb of the corpus spongiosum. Retrograde urethrography is the standard test to diagnose a communicating (open) Cowper duct syringocele, and MRI is used for further morphologic assessment. Cowperitis refers to inflammation of the gland and/or duct, and recurrent cowperitis is usually associated with an underlying syringocele, a urethral fistulous connection to the Cowper gland, or a perianal fistula. MRI allows detection of the underlying structural abnormality and the superimposed inflammation. Cowper stones are typically radiopaque and are found in both the Cowper gland and duct. A Cowper gland HHhemorrhagic cyst may be incidentally detected at MRI of the prostate, and follow-up MRI may be required to ensure evolution of hemorrhage and exclude an underlying neoplasm. Cowper gland carcinoma is rare and includes adenocarcinoma and adenoid cystic carcinoma subtypes. Transperineal US may be used for initial evaluation and CT and/or MRI are necessary for further characterization and staging. Cowper gland hyperplasia is a rare entity with few previous reports that may be incidentally detected at imaging and may mimic malignancy. ^©RSNA, 2022.

A multimodality review of male urethral imaging: pearls and pitfalls with an update on urethral stricture treatment

Optimum radiological assessment of the male urethra requires knowledge of the normal urethral anatomy and ideal imaging techniques based on the specific clinical scenario. Retrograde urethrography is the workhorse examination for male urethral imaging, usually utilized as the initial, and often solitary, modality of choice not only in the setting of trauma, but also in the pre- and post-operative evaluation of urethral strictures. There is, however, growing interest in utilization of ultrasound and magnetic resonance for evaluation of the male urethra owing to lack of ionizing radiation and improved delineation of the adjacent tissue. We review the various modalities utilized for imaging of the male urethra for a variety of known or suspected disorders, and provide an update on current treatments of urethral strictures. Additionally, we detail the key information needed by urologists to guide management of urethral strictures. We conclude with a brief discussion of neophallus urethral diseases following female-to-male sexual confirmation surgery.

Penile girth augmentation by injectable fillers: a comprehensive review of imaging features and inflammatory complications

Despite the extensive controversy and debate of penile girth augmentation, high demands for such procedures are increasing. Penile inflammation is not common sequel after penile filler augmentation, but when it occurs, it has serious complications that sometimes necessitate emergency surgical intervention. Imaging with a variety of modalities, including ultrasonography, magnetic resonance imaging, and ascending urethrogrphy plays a paramount role in the detection and assessment of these conditions. Inflammatory conditions after penile girth augmentation using injectable fillers are ranging from local granuloma to penile abscess formation or diffuse cellulitis that may extend to the scrotum, perineum or deep pelvic organs. Rapid diagnosis and evaluation of extensions are important to avoid associated morbidity and permanent deformity. Our purpose is to provide a practical review of relevant penile anatomy, imaging appearance and injection technique of different types of subcutaneous fillers used in penile girth augmentation, and inflammatory complications that may occur after these procedures. Brief descriptions of patient clinical information and imaging features of inflammatory complications will be included and correlated in actual cases.

Developments in Mannose-Based Treatments for Uropathogenic Escherichia coli-Induced Urinary Tract Infections

During their lifetime almost half of women will experience a symptomatic urinary tract infection (UTI) with a further half experiencing a relapse within six months. Currently UTIs are treated with antibiotics, but increasing antibiotic resistance rates highlight the need for new treatments. Uropathogenic Escherichia coli (UPEC) is responsible for the majority of symptomatic UTI cases and thus has become a key pathological target. Adhesion of type one pilus subunit FimH at the surface of UPEC strains to mannose-saturated oligosaccharides located on the urothelium is critical to pathogenesis. Since the identification of FimH as a therapeutic target in the late 1980s, a substantial body of research has been generated focusing on the development of FimH-targeting mannose-based anti-adhesion therapies. In this review we will discuss the design of different classes of these mannose-based compounds and their utility and potential as UPEC therapeutics.

MRI in patients with urethral stricture: a systematic review

Magnetic resonance imaging (MRI) is gaining acceptance as a diagnostic tool in urethral stricture disease. Numerous publications emphasize on the advantages of MRI including its ability to determine periurethral spongiofibrosis, thus overcoming the main limitation of retrograde urethrography (RUG). It is also becoming an alternative for sonourethrography (SUG), which is a highly subjective examination. Magnetic resonance urethrography (MRU) has become an increasingly appreciated tool for diagnosing patients with urethral stricture disease. Obtained data provides radiologists and urethral reconstructive surgeons with additional information regarding anatomical relationships and periurethral tissue details, facilitating further treatment planning. Considering the great prevalence of urethral stricture disease and necessity of using accurate, and acceptable diagnostic method, this review was designed to provide radiologists and clinicians with a systematic review of the literature on the use of MRI in the urethral stricture disease.

Ultrasonographic Imaging Features of Female Urethral and Peri-urethral Masses: A Retrospective Study of 95 Patients

The aim of this study was to assess the imaging features of urethral and peri-urethral masses on transvaginal or transperineal ultrasound (US) in a cohort of 95 women. In this retrospective study, medical records of 95 female patients with 98 asymptomatic or symptomatic urethral and peri-urethral masses were retrospectively reviewed. Data regarding patient demographic characteristics, symptoms, signs, imaging features on 2-D and 3-D transvaginal or transperineal US, diagnostic tests and physical and intra-operative findings were extracted. The US imaging features and clinicopathologic characteristics of each urethral or peri-urethral mass were compared. On ultrasound, 39 masses (in 39 patients) were diagnosed as urethral diverticula, which manifested mostly as complex cystic masses (24/39, 61.5%); 35 masses (in 33 patients) were diagnosed as para-urethral cysts, which manifested mostly as simple cystic masses (19/35, 54.3%); 13 hypo-echoic solid masses (in 12 patients) exhibiting blood flow signals on color Doppler imaging were diagnosed as urethral leiomyomas; hypo-echoic or heterogeneous solid masses (in 8 patients) exhibiting blood flow signals on color Doppler imaging were diagnosed as urethral caruncles, including one complicated by malignant transformation; solid masses with mixed echogenicity (in 2 patients) exhibiting blood flow signals on color Doppler imaging were diagnosed as urethral squamous cell carcinoma or adenocarcinoma, and a hypoechoic solid mass (in one patient) with blood-flow signals on color Doppler imaging was diagnosed as urethral condyloma associated with human papillomavirus infection. This study confirmed transvaginal or transperineal 2-D and 3-D ultrasonography to be a valid, non-invasive, cost-effective diagnostic modality for the differential diagnosis of urethral and periurethral masses.

Imaging of the adult male urethra, penile prostheses and artificial urinary sphincters

To discuss the imaging appearances of various pathologies affecting adult male urethra and to review the role of imaging in the assessment of artificial urinary sphincters and penile prostheses. Diagnosis of common male urethral diseases heavily depends on two conventional fluoroscopic techniques namely retrograde urethrography and voiding cystourethrography. These are useful in evaluating common urethral diseases like traumatic injury, infections, and strictures. Cross-sectional imaging can be useful in evaluating periurethral pathologies. Artificial urinary sphincters, slings, and periurethral bulking agents are used in the management of urinary incontinence and imaging can be utilized to detect complications in these devices. Cross-sectional imaging especially MRI plays a significant role in evaluating the different types of penile prostheses and their malfunctioning.

The Male Urethra: Imaging and Surgical Approach for Common Pathologies

Urethral pathology is common in clinical practice and important to recognize. It is essential to recognize urethral pathology on imaging and to understand how to best image the urethra. In this way, the radiologist can provide the urologist with the necessary information prior to intervention. Basic knowledge of commonly performed urethral surgeries can help the radiologist understand the expected appearance of the post-treatment urethra and common postoperative complications.

Isolated urethral metastasis from appendiceal mucinous adenocarcinoma

We are presenting a compelling case of a 61-year-old female with a history of appendiceal mucinous adenocarcinoma (AMA) with a new complaint of irritative lower urinary tract symptoms. Magnetic resonance imaging (MRI) showed a semi-circumferential, T2 hyperintense, rim enhancing, and lacking restricted diffusion lesion involving the urethra and infiltrating the right perineal and internal obturator muscles. The suspected differential diagnosis was urethral malignancy, based on her cancer history and MRI findings. After interdisciplinary consensus, the patient underwent excision of the lesion, and pathology was consistent with metastasis from the primary tumor. The urethra is a rare site of primary malignancy and metastatic disease. In particular, a non-contiguous metastatic disease involving the urethra is exceedingly rare. To the best of our knowledge, this is the first report of an AMA metastasizing to the urethra.

Elucidating vaginal fistulas on CT and MRI

Vaginal fistulas (VF) represent abnormal communications between the vagina and either the distal portion of the digestive system or the lower urinary tract, but lack an accepted classification and standardised terminology. Regardless of the underlying cause, these uncommon disorders result in profound physical, psychological, sexual and social distress to the patients.Since diagnosis of VF is challenging at gynaecologic examination, ano-proctoscopy and urethro-cystoscopy, imaging is crucial to confirm the fistula, to visualise its site, course and involved organ, and to characterise the underlying disease. The traditional conventional radiographic studies provided limited cross-sectional information and are nowadays largely replaced by CT and MRI studies.Aiming to provide radiologists with an increased familiarity with VF, this pictorial paper summarises their clinical features, pathogenesis and therapeutic approach, and presents the appropriate CT and MRI acquisition and interpretation techniques that vary according to the anatomic site and termination of the fistula. The current role of state-of-the art CT and MRI is presented with examples regarding both entero- (involving the colon, rectum and anus) and urinary (connecting the bladder, distal ureter or urethra) VF. The resulting combined anatomic and functional cross-sectional information is crucial to allow a correct therapeutic choice and surgical planning.

Multimodality imaging of the male urethra: trauma, infection, neoplasm, and common surgical repairs

OBJECTIVE

The aim of this article is to describe the indications and proper technique for RUG and MRI, their respective image findings in various disease states, and the common surgical techniques and imaging strategies employed for stricture correction.

RESULTS

Because of its length and passage through numerous anatomic structures, the adult male urethra can undergo a wide array of acquired maladies, including traumatic injury, infection, and neoplasm. For the urologist, imaging plays a crucial role in the diagnosis of these conditions, as well as complications such as stricture and fistula formation. While retrograde urethrography (RUG) and voiding cystourethrography (VCUG) have traditionally been the cornerstone of urethral imaging, MRI has become a useful adjunct particularly for the staging of suspected urethral neoplasm, visualization of complex posterior urethral fistulas, and problem solving for indeterminate findings at RUG.

CONCLUSIONS

Familiarity with common urethral pathology, as well as its appearance on conventional urethrography and MRI, is crucial for the radiologist in order to guide the treating urologist in patient management.

Infectious and Inflammatory Diseases of the Urinary Tract: Role of MR Imaging

Urinary tract infection (UTI) is among the most common of bacterial infections. Imaging studies are only required in cases of complicated UTIs. Ultrasound remains the first-line imaging method; however, CT is the gold standard for evaluation of UTIs. MR imaging's improved contrast resolution and absence of ionizing radiation may recommend its use for assessment of lower UTIs. Furthermore, MR imaging performs with diagnostic accuracy at least similar to CT in complicated UTIs, except for the identification of calculi and emphysematous pyelonephritis. In this article, the role of MR imaging for the evaluation of infectious and inflammatory disease processes of the urinary tract is reviewed.

A rare case of hydrometrocolpos from persistent urogenital sinus in patient affected by adrenogenital syndrome

Persistent urogenital sinus (PUGS) is a congenital pathological condition characterized by an abnormal communication between the urethra and vagina, which has an estimated incidence of 0.6/10,000 female births. It could be the only known malformation or part of a syndrome. PUGS is commonly shown by a pelvic mass, related to a distended bladder, hydrometrocolpos which is due to an obstruction leading to the dilation of the vagina and uterus (i.e., imperforate hymen, transverse vaginal septum or atresia, and PUGS) or both. We present a case of female patient with classical congenital adrenal hyperplasia, diagnosed on the 7th day of life, with ambiguous genitalia, untreated surgically only with hormone therapy by parental decision. The patient, at the age of 5 years and 5 months, came to our observation for a pelvic ultrasound, which revealed retrovesical neoformation with anechoic content and regular walls. We performed the ultrasound examination that showed the dilation of the cervix and the vaginal canal with anechoic finely corpuscolated content in the declining portion, compatible with hydrometrocolpos from probable persistence of the urogenital sinus. The voiding cystourethrography (VCUG) confirmed the ultrasound diagnosis, with evidence of urogenital sinus. In conclusion, ultrasound is the first diagnostic tool, but need to be completed by other technical procedures, which VCUG or magnetic resonance imaging to observe the site of fusion of the urinary and genital tract.

Skene duct adenocarcinoma in a patient with an elevated serum prostate-specific antigen level: a case report

Background

Female urethral carcinoma is a very rare disease that accounts for 0.02% of malignant diseases in female patients.

Case presentation

A 70-year-old Asian Japanese woman with a urethral tumor was referred to our hospital to undergo further examination. Biopsy specimens showed urethral adenocarcinoma that was positive for prostate-specific antigen. Her serum prostate-specific antigen level before surgery was 34.4 ng/ml. Urethral tumor resection with pelvic lymph node resection was performed. Her serum prostate-specific antigen level decreased to < 0.01 ng/ml after surgery.

Conclusions

We report a very rare case of Skene duct adenocarcinoma in a female patient with serum prostate-specific antigen elevation.

The utility of CT and MRI in detecting male urethral recurrence after radical cystectomy

PURPOSE

To evaluate the utility of computed tomography (CT) and magnetic resonance imaging (MRI) in detecting male urethral recurrence (UR).

MATERIALS AND METHODS

Between December 2008 and March 2016, 12 men (age range 61-85 years; median, 74 years) with urethral bloody discharge or pain were histologically confirmed as UR after radical cystectomy due to urothelial carcinoma. Of these patients, eight underwent both CT and MRI. The remaining four patients underwent CT only. CT and MRI were compared regarding UR detection rate. CT and MRI were also evaluated to determine which modality was more accurate for depicting UR. UR detection rate of each MRI sequence were recorded. Standard reference was biopsy or urethrectomy in 11 patients and size change in one patient after treatment.

RESULTS

UR detection rate with CT was 41.7% (5/12), while that with MRI was 100% (8/8) (p = 0.0147). Of the eight patients who were diagnosed UR with MRI, six were detected with MRI alone and two with both MRI and CT (p = 0.0313). UR detection rates of T2-weighted, T1-weighted, diffusion-weighted, and contrast-enhanced MRI were 87.5% (7/8), 62.5% (5/8), 100% (5/5), and 87.5% (7/8), respectively.

CONCLUSION

MRI is superior to CT in detecting male URs in symptomatic patients after radical cystectomy. T2-weighted, diffusion-weighted, and contrast-enhanced MRI sequences are useful for detecting male UR.

Does MRI help in the pre - operative evaluation of pelvic fracture urethral distraction defect? - A pilot study

Objectives

To study the usefulness of MRI in preoperative evaluation of PFUDD. Can MRI provide additional information on urethral distraction defect (UDD) and cause of erectile dysfunction (ED)?

Materials and Methods

In this prospective study, consecutive male patients presenting with PFUDD were included from Feb 2011 till Dec 2012. Those with traumatic spinal cord injury and pre-existing ED were excluded. Patients were assessed using IIEF questionnaire, retrograde urethrogram and micturating cystourethrogram (RGU+MCU) and MRI pelvis. Primary end point was erectile function and secondary end point was surgical outcome.

Results

Twenty patients were included in this study. Fourteen patients (70%) were ≤40years; fifteen patients (75%) had ED, seven patients (35%) had severe ED. MRI findings associated with ED were longer median UDD (23mm vs. 15mm, p=0.07), cavernosal injury (100%, p=0.53), rectal injury (100%, p=0.53), retropubic scarring (60%, p=0.62) and prostatic displacement (60%, p=0.99). Twelve patients (60%) had a good surgical outcome, five (25%) had an acceptable outcome, three (15%) had a poor outcome. Poor surgical outcome was associated with rectal injury (66.7%, p=0.08), cavernosal injury (25%, p=0.19), retropubic scarring (18.1%, p=0.99) and prostatic displacement (16.7%, p=0.99). Five patients with normal erections had good surgical outcome. Three patients with ED had poor outcome (20%, p=0.20).

Conclusions

MRI did not offer significant advantage over MCU in the subgroup of men with normal erections. Cavernosal injury noted on MRI strongly correlated with ED. Role of MRI may be limited to the subgroup with ED or an inconclusive MCU.

Magnetic Resonance Imaging and Pelvic Fracture Urethral Injuries

Pelvic fracture urethral injuries (PFUI) are devastating lesions that lead to fibrosis and urethral disruption, which result in recurrent strictures, urinary incontinence, fistulae, and even erectile dysfunction, representing a management problem for the urologist. Magnetic resonance imaging (MRI) may be a valuable tool in establishing or confirming the diagnosis by providing detailed anatomy and estimating disease extent. We present a comprehensive review of the current literature on the role of MRI on diagnostic evaluation and surgical management of patients with PFUI.

Clinical and Imaging Features of Noncutaneous Melanoma

OBJECTIVE

The purpose of this article is to summarize the epidemiologic characteristics, clinical aspects, and radiologic appearance of as well as the management considerations and differential diagnoses for noncutaneous primary melanomas occurring at specific anatomic sites. Primary ocular, sinonasal, meningeal, biliary, adrenal, alimentary tract, and genitourinary melanomas are highlighted.

CONCLUSION

Noncutaneous primary melanomas are a complex group of malignancies with biologic findings that are unique when compared with findings for cutaneous melanomas. Each noncutaneous primary melanoma has its own specific diagnostic and management challenges, depending on the anatomic location where they arise.

A very large leiomyoma of the urethra: A case report

INTRODUCTION

Leiomyomas are benign mesenchymal tumours of smooth muscle origin. They are the most common uterine masses in women of reproductive age group and may be related to the hormonal status. Urethral leiomyomas are very rare. According to the literature, the mean diameter of the urethral leiomyomas is 3.7 cm.

CASE REPORT

We report a case of a very large leiomyoma of the urethra. A 40-year-old women woman was admitted to our department for a giant vaginal mass. She complained of haematuria, dysuria, recurrent urinary tract infections and dyspareunia. The physical evaluation demonstrated a 6 × 5.5 cm neoformation involving the distal tract of the urethra. The patient underwent an ultrasonography and then a magnetic resonance that suggested the diagnosis of leiomyoma. The neoformation was excised through a suburethral incision.

CONCLUSIONS

The patient was discharged after 3 days and no intraoperative and postoperative complications occurred. The Foley catheter was removed after a week. The patient was continent to urine, and at 6 months follow-up, the patient was symptom free and no recurrences occurred.

Contemporary Management of Primary Distal Urethral Cancer

Primary urethral cancer is one of the rare urologic tumors. Distal urethral tumors are usually less advanced at diagnosis compared with proximal tumors and have a good prognosis if treated appropriately. Low-stage distal tumors can be managed successfully with a surgical approach in men or radiation therapy in women. There are no clear-cut indications for the choice of the most appropriate treatment modality. Organ-preserving modalities have shown effective and should be used whenever they do not compromise the oncological safety to decrease the physical and psychological trauma of dismemberment or loss of sexual/urinary function.

Diagnosing urethral duplication including a novel radiological diagnostic algorithm

Until this 24 -year -old male was sexually active, the small dimple on his penile glans had never required any consideration. However, persistent focal irritation during sexual intercourse compelled him to pursue medical attention. Following urological consultation he was referred for imaging evaluation that demonstrated urethral duplication. After determining the subtype classification, urologic repair was successfully completed without complication. Urethral duplication is an exceedingly rare genitourinary anatomic anomaly with a variety of presentations and symptomatology. The vast majority of urethral duplications are diagnosed within the paediatric and adolescent populations. Although urethral duplication is managed by urologists, imaging identification of the particular subtype is critical for proper management planning. A thorough review of existing literature on the classification strategies and diagnostic criteria is discussed. Owing to the scarcity of clinical experience, a wide variety of diagnostic approaches are described. These often include unnecessary radiation, invasiveness and cost. A strategic and efficient diagnostic algorithm is included to guide future imaging evaluation of suspected urethral duplication. This provides the essential clinical information, while minimis ing radiation, invasiveness and cost.

Simple diagrammatic method to delineate male urethra in prostate cancer radiotherapy: an MRI based approach

Stereotactic body radiotherapy (SBRT) is being increasingly utilized in the treatment of prostate cancer. With the advent of high-precision radiosurgery systems, it is possible to obtain dose distributions akin to high-dose rate brachytherapy with SBRT. However, urethral toxicity has a significant impact on the quality of life in patients with prostate cancer. Contouring the male urethra on a CT scan is difficult in the absence of an indwelling catheter. In this pictorial essay, we have used the MRI obtained for radiotherapy planning to aid in the delineation of the male urethra and have attempted to define guidelines for the same.

Cross-sectional imaging of complicated urinary infections affecting the lower tract and male genital organs

Complicated urinary tract infections (C-UTIs) are those associated with structural or functional genitourinary abnormalities or with conditions that impair the host defence mechanisms, leading to an increased risk of acquiring infection or failing therapy. C-UTIs occur in patients with risk factors such as neurogenic dysfunction, bladder outlet obstruction, obstructive uropathy, bladder catheterisation, urologic instrumentation or indwelling stent, urinary tract post-surgical modifications, chemotherapy- or radiation-induced damage, renal impairment, diabetes and immunodeficiency.

Multidetector CT and MRI allow comprehensive investigation of C-UTIs and systemic infection from an unknown source. Based upon personal experience at a tertiary care hospital focused on the treatment of infectious illnesses, this pictorial essay reviews with examples the clinical features and cross-sectional imaging findings of C-UTIs affecting the lower urinary tract and male genital organs. The disorders presented include acute infectious cystitis, bladder mural abscesses, infections of the prostate and seminal vesicles, acute urethritis and related perineal abscesses, funiculitis, epididymo-orchitis and scrotal abscesses. Emphasis is placed on the possible differential diagnoses of lower C-UTIs.

The aim is to provide radiologists greater familiarity with these potentially severe disorders which frequently require intensive in-hospital antibiotic therapy, percutaneous drainage or surgery.

Teaching Points

• Complicated urinary tract infections occur in patients with structural or functional risk factors.

• CT and MRI comprehensively investigate complicated urinary infections and sepsis from unknown sources.

• Infections of the urinary bladder, prostate, seminal vesicles, urethra and scrotum are presented.

• Emphasis is placed on differential diagnoses of complicated lower urogenital infections.

• Unsuspected urinary infections may be detected on CT performed for other clinical reasons.

Urine Flow Dynamics Through Prostatic Urethra With Tubular Organ Modeling Using Endoscopic Imagery

Voiding dysfunction is common in the aged male population. However, the obstruction mechanism in the lower urinary tract and critical points for obstruction remains uncertain. The aim of this paper was to develop a system to investigate the relationship between voiding dysfunction and alteration of the shape of the prostatic urethra by processing endoscopic video images of the urethra and analyzing the fluid dynamics of the urine stream. A panoramic image of the prostatic urethra was generated from cystourethroscopic video images. A virtual 3-D model of the urethra was constructed using the luminance values in the image. Fluid dynamics using the constructed model was then calculated assuming a static urethra and maximum urine flow rate. Cystourethroscopic videos from 11 patients with benign prostatic hyperplasia were recorded around administration of an alpha-1 adrenoceptor antagonist. The calculated pressure loss through the prostatic urethra in each model corresponded to the prostatic volume, and the improvements of the pressure loss after treatment correlated to the conventional clinical indices. As shown by the proposed method, the shape of the prostatic urethra affects the transporting urine fluid energy, and this paper implies a possible method for detecting critical lesions responsible for voiding dysfunction. The proposed method provides critical information about deformation of the prostatic urethra on voiding function. Detailed differences in the various types of relaxants for the lower urinary tract could be estimated.

Magnetic resonance imaging of solid urethral and peri-urethral lesions

Solid urethral and peri-urethral lesions are rare and encompass benign and malignant aetiologies. A diagnosis without imaging is often challenging secondary to non-specific clinical symptoms and overlapping findings at the time of physical examination. Magnetic resonance (MR) imaging may be helpful in confirming a diagnosis while providing anatomical detail and delineating disease extent. This article reviews the normal MR anatomy of the male and female urethra, the MR appearance of solid primary and secondary urethral lesions, and the MR appearance of solid urethral lesion mimics.

Teaching points

• MRI is an important imaging technique in the evaluation of the spectrum of solid urethral lesions.

• With excellent soft tissue resolution, MR is accurate in staging primary urethral carcinoma.

• Disruption of the zonal anatomy of the female urethral wall indicates peri-urethral extension.

• Be aware of benign urethral lesions, particularly those that may mimic solid urethral masses.

EAU guidelines on primary urethral carcinoma

CONTEXT

The European Association of Urology (EAU) Guidelines Group on Muscle-Invasive and Metastatic Bladder Cancer prepared these guidelines to deliver current evidence-based information on the diagnosis and treatment of patients with primary urethral carcinoma (UC).

OBJECTIVE

To review the current literature on the diagnosis and treatment of patients with primary UC and assess its level of scientific evidence.

EVIDENCE ACQUISITION

A systematic literature search was performed to identify studies reporting urethral malignancies. Medline was searched using the controlled vocabulary of the Medical Subject Headings database, along with a free-text protocol.

EVIDENCE SYNTHESIS

Primary UC is considered a rare cancer, accounting for <1% of all malignancies. Risk factors for survival include age, tumour stage and grade, nodal stage, presence of distant metastasis, histologic type, tumour size, tumour location, and modality of treatment. Pelvic magnetic resonance imaging is the preferred method to assess the local extent of urethral tumour; computed tomography of the thorax and abdomen should be used to assess distant metastasis. In localised anterior UC, urethra-sparing surgery is an alternative to primary urethrectomy in both sexes, provided negative surgical margins can be achieved. Patients with locally advanced UC should be discussed by a multidisciplinary team of urologists, radiation oncologists, and oncologists. Patients with noninvasive UC or carcinoma in situ of the prostatic urethra and prostatic ducts can be treated with a urethra-sparing approach with transurethral resection and bacillus Calmette-Guérin (BCG). Cystoprostatectomy with extended pelvic lymphadenectomy should be reserved for patients not responding to BCG or as a primary treatment option in patients with extensive ductal or stromal involvement.

CONCLUSIONS

The 2013 guidelines document on primary UC is the first publication on this topic by the EAU. It aims to increase awareness in the urologic community and provide scientific transparency to improve outcomes of this rare urogenital malignancy.

Length of urethra in the Indian adult male population

OBJECTIVE

The urethral length has not been measured in the Indian population. Even the international literature in this arena is very sparse. This paper is an attempt to develop a simple anatomical database for urethral length.

MATERIALS AND METHODS

Between January 2010 and April 2011, the urethral lengths of 422 adult male patients who required catheterization as part of regular treatment at our hospital, were recorded after obtaining consent from the patients and from the scientific and ethics review boards of the institution. Patients with history of prostatic or urethral abnormalities were excluded. The balloon of a sterile Foley's catheter was inflated using 10 cc of saline. The length from the junction of the balloon to the 'Y' junction of the Foley was measured. The catheter was then passed into the bladder and re-inflated to same volume. The penis was gently straightened and the length of the catheter outside the penis was measured till the premarked point at the 'Y' junction. Subtracting this from the original length gave the length of the urethra.

RESULTS

The mean length of the urethra was 17.55 + 1.42 cm with a range between 14 and 22.5 cm.

CONCLUSIONS

Literature in which the length of the normal adult male urethra is recorded for a significant sample size is very scarce. Our data adds to basic anatomic information of the male urethra specific to the Indian population.

STATISTICAL METHODS

Descriptive statistical analysis was performed. The non-linear regression analysis was employed to find the normative values of urethral length according to age class.

Imaging of unusual perineal masses

OBJECTIVE

The purpose of this article is to describe the radiologic features of unusual tumors that occur in the perineum.

CONCLUSION

The perineal space is often overlooked because of the infrequency of abnormalities. Accurate image interpretation and visualization of extent of pathology is important for proper management. Trauma and infectious diseases occur in the acute setting, whereas tumors are common in the chronic setting. Cross-sectional imaging plays a crucial role in depicting perineal anatomy and evaluating the extent of disease.

[Malignant degeneration in a urethral diverticulum: an uncommon complication in a common condition]

Acquired urethral diverticula are relatively common in women. They are usually asymptomatic but they can lead to complications; infection and stones are the most common complications. Malignant degeneration with the development of a malignant tumor in the diverticulum is a rare complication that must be taken into account. Few cases of malignant tumors in urethral diverticula have been reported. We present the case of a woman diagnosed with a malignant tumor in a urethral diverticulum. We review the imaging findings for urethral diverticula and the complications that can arise in this condition.

Impact of urinary catheterization on dosimetry after prostate implant brachytherapy with palladium-103 or iodine-125

PURPOSE

Postoperative dosimetry is integral to quality assurance for prostate brachytherapy. Images on Day 0 are typically obtained with a contrast-filled urinary catheter in place for urethral dose calculations. However, expansion of the urethra and perhaps the prostate by the catheter may affect target coverage. We assessed the effect of urinary catheterization on target dosimetry after implantation with palladium-103 ((103)Pd) or iodine-125 ((125)I) seeds.

METHODS AND MATERIALS

Patients were 29 consecutive men with postimplant dosimetry calculated with and without a urinary catheter after brachytherapy seed implantation; 19 patients received (103)Pd seeds and 10 patients received (125)I seeds. In each case, 14-French caude tip urinary catheters were placed before implantation, and axial CT slices of the pelvis were obtained before and after catheter removal for postimplant dosimetry. Dosimetric parameters were measured and compared with paired Student's t tests. Trends were assessed by linear regression with the Pearson correlation coefficient.

RESULTS

Removal of the urinary catheter significantly improved V(100) and D(90) for (103)Pd implants (mean±standard deviation (SD), 2.7%±4.2%; range, -0.4% to 15%; p=0.011 and mean±SD, 4.0%±3.4%; range, -0.1% to 13.8%; p<0.01, respectively). For (125)I implants, catheter removal improved D(90) (mean±SD, 1.5%±1.8%; range, -1.3% to 4.2%; p=0.027). For the (103)Pd group, the magnitude of change in V(100) correlated with prostate size (R(2)=0.16) and source number (R(2)=0.15).

CONCLUSIONS

Urinary catheterization can artificially reduce target coverage after prostate implant brachytherapy. The patients undergoing (103)Pd implantation with smaller (<30cm(3)) prostates and fewer (<90) sources are particularly susceptible to reduced D(90) and V(100) when a urinary catheter is present.

Non-surgical treatment of primary female urethral cancer

Primary carcinomas of the female urethra are extremely rare, with an annual incidence of less than ten in one million. Currently, there is no consensus regarding management of this malignancy. However, there have been several case reports demonstrating the efficacy of chemoradiation in the treatment of female urethral cancer. In this report we present two cases of female primary urethral adenocarcinoma that were treated by concomitant chemotherapy and external beam radiotherapy, followed by interstitial brachytherapy.

Surgery for urethral cancer

Primary urethral cancers represent less than 1% of genitourinary malignancy. Given this is an uncommon disease, there are limited data to guide diagnostic and treatment strategies. Surgical extirpation remains the standard for most patients, with the addition of chemotherapy and radiation therapy in select patients. The surgical approach to urethral cancer depends largely on the location and extent of the tumor.