Imaging of the acute scrotum: keys to a rapid diagnosis of acute scrotal disorders

ACR Appropriateness Criteria® Acute Onset of Scrotal Pain-Without Trauma, Without Antecedent Mass: 2024 Update

Acute scrotum is a medical emergency that requires prompt accurate diagnosis to appropriately triage potentially surgical conditions. Numerous differential diagnoses with overlapping clinical presentations make this a diagnostic challenge. Ultrasound is the established first-line imaging modality for acute scrotal disease and can be used to diagnose most scrotal disorders promptly and with high accuracy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Decoding Acute Scrotum: Diagnostic Accuracy of Ultrasound in Urgent Clinical Settings

Background Acute scrotum is a medical emergency commonly encountered in clinical practice, particularly in pediatric and adolescent populations. It is characterized by sudden onset of scrotal pain and may involve swelling, redness, or tenderness. The most common etiologies include testicular torsion, epididymo-orchitis, trauma, and, less frequently, tumors. Early and accurate diagnosis is critical, especially in cases of testicular torsion, where timely surgical intervention is required to preserve testicular viability. Ultrasound (US), particularly high-resolution gray-scale imaging combined with color Doppler (CD), has emerged as the primary imaging modality for evaluating acute scrotal conditions due to its accessibility, non-invasiveness, and high diagnostic accuracy. Aims and objectives This study aims to assess the diagnostic accuracy of US in differentiating the causes of acute scrotum, specifically focusing on testicular torsion, epididymo-orchitis, and varicocele. We also evaluate its role in reducing unnecessary surgical explorations and improving clinical decision-making in urgent settings. Materials and methods This retrospective observational study was conducted in a tertiary care center in Puducherry, India. A total of 250 male patients, ranging in age from 10 to 70 years, presented with acute scrotal pain over the 12-month study period. Inclusion criteria included all patients with sudden scrotal pain, regardless of clinical suspicion of underlying pathology. US scans were performed using a 7.5- to 12-MHz linear transducer. Gray-scale imaging was used to evaluate the testes, epididymis, spermatic cord, scrotal wall, and inguinal region, while CD was used to assess vascular flow. Statistical analysis was conducted using SPSS Version 18 (IBM Corp., Armonk, NY). Diagnostic accuracy was calculated based on sensitivity, specificity, positive predictive value, and negative predictive value. Results The most common cause of acute scrotum was inflammatory pathology, including epididymo-orchitis, accounting for 56.4% of cases (141 patients). Varicocele was the second most common cause, diagnosed in 11.6% of patients (29 cases), while hernias and epididymal cysts were found in 8% and 7.6% of cases, respectively. Testicular torsion was diagnosed in 2% of cases (five patients). US demonstrated high diagnostic accuracy for inflammatory pathologies, with sensitivity and specificity reaching 97% and 96%, respectively. The sensitivity for testicular torsion was 62%, reflecting the challenges in diagnosing partial or intermittent torsion, while specificity was high at 99%. US's performance in identifying varicocele was excellent, with a sensitivity of 93% and specificity of 98%. Conclusion US, especially when combined with CD, is an indispensable tool in the emergency evaluation of acute scrotum. It provides high diagnostic accuracy for inflammatory pathologies and varicocele while serving as an effective screening modality for testicular torsion. This study reinforces the role of US in reducing unnecessary surgical explorations, guiding clinical management, and improving patient outcomes in urgent clinical settings.

Acute Idiopathic Scrotal Edema, an Underrecognized Cause of Scrotal Pain in Children: A Case Report and Literature Review

Acute idiopathic scrotal edema is a clinical entity predominant in children under 10 years whose true incidence is unknown in our setting. Diagnosis is challenging and avoids unnecessary surgeries. We present the case of an idiopathic acute scrotal edema with ultrasound findings highly suggestive of the diagnosis, which was managed conservatively with complete signs and symptoms resolution after discharge. We aim to review the ultrasound characteristics and differential diagnosis of this disorder.

Imaging findings in inflammatory disease of the genital organs

This review focuses on inflammatory diseases of female and male genital organs and discusses their epidemiology, pathogenesis, clinical presentation, and imaging findings. The female section covers pelvic inflammatory disease (PID) primarily caused by sexually transmitted infections (STIs) that affect the uterus, fallopian tubes, and ovaries. Unusual causes such as actinomycosis and tuberculosis have also been explored. The male section delves into infections affecting the vas deferens, epididymis, testes, prostate, and seminal vesicles. Uncommon causes such as tuberculosis, and Zinner syndrome have also been discussed. In addition, this review highlights other conditions that mimic male genital tract infections such as vasculitis, IgG4-related diseases, and sarcoidosis. Accurate diagnosis and appropriate management of these inflammatory diseases are essential for preventing serious complications and infertility. Imaging modalities such as ultrasound, magnetic resonance imaging, and computed tomography play a crucial role in diagnosis. Understanding the diverse etiologies and imaging findings is vital for the effective management of inflammatory diseases of the genital organs.

Point-of-care ultrasonography for the diagnosis and manual detorsion of testicular torsion

Testicular torsion is a urological emergency caused by the loss of testicular tissue due to ischemic damage. Rapid diagnosis and urgent treatment play a crucial role in the management of testicular torsion. Manual detorsion can be performed at the bedside, thereby reducing the duration of ischemia. Recent studies have reported the use of point-of-care ultrasonography for diagnosing testicular torsion; however, no review article has focused on the ultrasonographic findings pertaining to manual detorsion. This review describes the diagnosis of testicular torsion and the ultrasonographic indications for manual detorsion. Spermatic cord twisting or the whirlpool sign, absence of or decreased blood flow within the affected testis, abnormal testicular axis, abnormal echogenicity, and enlargement of the affected testis and epididymis due to ischemia are the sonographic findings associated with testicular torsion. The following findings are considered indications for manual detorsion: direction of testicular torsion, i.e., inner or outer direction (ultrasonographic accuracy of 70%), and the degree of spermatic cord twist. The following sonographic findings are used to determine whether the treatment was successful: presence of the whirlpool sign and the degree and extent of perfusion of the affected testis. Misdiagnosis of the direction of manual detorsion, a high degree of spermatic cord twisting and insufficient detorsion, testicular compartment syndrome, and testicular necrosis were found to result in treatment failure. The success of manual detorsion is determined based on the symptoms and sonographic findings. Subsequent surgical exploration is recommended in all cases, regardless of the success of manual detorsion.

Multiparametric Ultrasound for Diagnosing Testicular Lesions: Everything You Need to Know in Daily Clinical Practice

BACKGROUND

Ultrasonography (US) represents the gold standard imaging method for the assessment of testicular lesions (TL). The gray-scale (GSUS) and color-Doppler (CDUS) ultrasound examination allow sonographers to investigate the size, margins, echotexture, and vascular features of TLs with the aim to differentiate benign from malignant lesions. Recently, the use of contrast-enhanced US (CEUS) and sonoelastography (SE) has led to further improvements in the differential diagnosis of TL. Although GSUS and CDUS are often sufficient to suggest the benign or malignant nature of the TL, CEUS can be decisive in the differential diagnosis of unclear findings, while SE can help to strengthen the diagnosis. The contemporary combination of GSUS, CDUS, CEUS, and SE has led to a new diagnostic paradigm named multiparametric US (mp-US), which is able to provide a more detailed characterization of TLs than single techniques alone. This narrative and pictorial review aimed to describe the mp-US appearance of several TLs.

METHODS

An extensive Medline search was performed to identify studies in the English language focusing on the mp-US evaluation of TLs.

RESULTS

A practical mp-US "identity card" and iconographic characterization of several benign and malignant TLs is provided herein.

CONCLUSIONS

The mp-US characterization of TL reported herein can be useful in daily clinical practice.

Pneumatosis: Appearances on CT Imaging

BACKGROUND

Pneumatosis is a general term used to designate the presence of spontaneous air or gas leaks into the body's compartments.

PURPOSE

In this paper, we provide an overview of gas originating from different sites and present the most common routes by which air may escape free to surrounding or distant tissues.

METHODS

On the basis of 45 interesting clinical cases, we discuss the CT imaging characteristics of thoracic and spinal pneumatosis, better known as pneumomediastinum and pneumorrhachis. In addition, we present craniocervical pneumatosis manifesting as subcutaneous emphysema.

RESULTS

Isolated pneumatosis was diagnosed in 12 (27%) of the 45 patients, manifesting as craniocervical free air or pneumoperitoneum. In 28 (62%) patients with pneumomediastinum, 12 (43%) had concomitant pneumothorax. Soft tissue emphysema was seen in 24 (52%) patients. One of the patients with generalized pneumatosis had craniocervical and extensive soft tissue emphysema, in conjunction with pneumomediastinum, pneumothorax, and pneumoperitoneum. Intraspinal pneumatosis was always coupled with pneumomediastinum.

CONCLUSION

Pneumatosis may not be as uncommon as it seems, and indeed, this condition may need to be recognized early as it can be an alarming sign of serious pathology.

Visualizing the early-stage testicular torsion by dual-modal photoacoustic and ultrasound imaging

Delayed treatment of testicular torsion (TT) can lead to permanent loss of reproductive capacity. Photoacoustic imaging (PAI) and ultrasound imaging (USI) was tested for detecting TT at early stage in mice based on PAI-obtained oxygen saturation (sO2), and USI-collected color pixel density (CPD), peak systolic velocity (PSV) and resistance index (RI). For complete TT, both CPD (9.08 % ± 3.084 to almost zero) and sO2 data (70.09 % ± 1.656-59.84 % ± 1.427) showed an significant change 2 h post-torsion. For incomplete TT, sO2 data exhibited a strong time relationship (Mean values: 6 h, 64.83 % ± 1.898; 12 h, 60.67 % ± 3.555; 24 h, 57.85 % ± 3.575; P < 0.05). However, USI-collected CPD, PSV or IR data from the same TT models showed no significant difference. This study indicated that USI and PAI could identify complete TT. Meanwhile, PAI has shown great potential in the diagnosis of incomplete TT within 24 h based on time-related sO2 map.

Progress in Multidisciplinary Treatment of Fournier's Gangrene

Fournier's gangrene (FG) is a life-threatening and special form of necrotizing fasciitis, characterized by occult onset, rapid progress and high mortality, occurring mainly in men over 50 years of age. Risk factors of FG include diabetes, HIV infection, chronic alcoholism and other immunosuppressive state. FG was previously considered as an idiopathic disease, but in fact, three quarters of the infections originated from the skin, urethra and gastrointestinal tract. Initial symptoms of FG are often inconsistent with severity and can progress promptly to fatal infection. Although the treatment measures of FG have been improved in recent years, the mortality does not seem to have decreased significantly and remains at 20% - 30%. The time to identify FG and the waiting period before surgical debridement are directly related to the prognosis. Therefore, in addition to the combination of intensive fluid resuscitation and broad-spectrum antibiotics, treatment of FG should particularly emphasize the importance of early surgical debridement assisted with fecal diversion and skin reconstruction when necessary. This paper is to briefly summarize the progress in the definition, epidemiology, clinical manifestations, diagnosis, treatment and prognosis of Fournier's gangrene in recent years, more importantly, illustrates the importance of multidisciplinary cooperation in the management of FG.

External Male Genitalia in Henoch-Schönlein Syndrome: A Systematic Review

The external genitalia are notoriously implicated in every fifth male with Henoch−Schönlein syndrome. Nonetheless, the underlying conditions are poorly categorized. To characterize the involvement of the external male genitalia in this vasculitis, we performed a systematic review of the literature. For the final analysis, we selected 85 reports published between 1972 and 2022, which reported on 114 Henoch−Schönlein cases (≤ 18 years, N = 104) with a penile (N = 18), a scrotal (N = 77), or both a penile and a scrotal (N = 19) involvement. The genital involvement mostly appeared concurrently with or after the cutaneous features of Henoch−Schönlein syndrome, while it preceded the presentation of Henoch−Schönlein syndrome in 10 cases. Patients with penile involvement (N = 37) presented with swelling (N = 26), erythema (N = 23), and purpuric rash (N = 15). Most patients were otherwise asymptomatic except for transient micturition disorders (N = 2) or priapism (N = 2). Patients with scrotal involvement (N = 96) presented with pain (N = 85), swelling (N = 79), erythema (N = 42), or scrotal purpura (N = 22). The following scrotal structures were often involved: scrotal skin (N = 83), epididymis (N = 49), and testes (N = 39). An ischemic testicular damage was noted in nine patients (four with torsion and five without). The scrotal skin involvement was mostly bilateral, while that of the epididymis and testis were mostly (p < 0.0001) unilateral (with a significant predilection for the left side). In conclusion, this analysis allows for better categorization of the involvement of external male genitalia in Henoch−Schönlein vasculitis. Scrotal involvement can result from skin inflammation, epididymitis, orchitis, or testicular ischemia.

Do Not Get It Twisted: Common and Uncommon Manifestations of Testicular Torsion

Color flow and spectral Doppler ultrasound are the backbone of scrotal imaging when evaluating acute scrotal pain. Testicular Torsion is one of the most common causes of acute scrotal pain but can be a challenging diagnosis both clinically and sonographically. This article will review the pertinent Doppler ultrasound findings that can help make the diagnosis of both complete and partial torsion. A review of other causes of testicular ischemia will also be included as these pathologies can mimic Testicular Torsion.

Sonography Findings Predict Testicular Viability in Pediatric Patients With Testicular Torsion

Background: Testicular torsion poses a pediatric surgical emergency that necessitates rapid diagnosis and surgery to prevent testicular loss. We sought to determine whether any particular findings on Doppler ultrasound (US) were predictive of testicular viability in pediatric patients with testicular torsion.

Materials and methods: We identified males between ages one and 18 years who experienced testicular torsion over a six-year period (January 1, 2015-December 31, 2020). All patients were evaluated at our institution’s emergency department by a pediatric urologist and underwent a Doppler scrotal US.

Results: Of the 140 patients with testicular torsion, 56 (40%) had a non-viable testis and underwent an orchiectomy, while 84 (60%) had a viable testis and orchiopexy. Testicular heterogeneity (47 [84%] vs 48 [57%], p = 0.001), epididymis heterogeneity (23 [41%] vs 21 [25%], p = 0.063), and scrotal wall thickening (25 [45%] vs 5 [6%], p < 0.001) were significantly associated with a non-viable testis. Epididymis heterogeneity (adj. odds ratio [OR] = 0.33 [0.13, 0.79], p = 0.013) and scrotal wall thickening (adj. OR = 0.08 [0.03, 0.24], p < 0.001) exhibited significantly lower odds for viability. Testicular heterogeneity and scrotal wall thickening were more likely to develop with a longer duration of symptoms (both p < 0.001).

Conclusion: Our study determined that certain Doppler scrotal US findings, specifically, testicular and epididymal heterogeneity as well as a thickened scrotal wall, are associated with testicular demise in patients with testicular torsion. As testicular heterogeneity and scrotal wall thickening are more likely to arise with a longer symptom duration, an urgent diagnosis and prompt surgical intervention are imperative to avert testicular loss.

Scrotal Pain Caused by a Segmental Testicular Infarct

Case Presentation

A 44-year-old Black male presented to the emergency department with left scrotal pain. His initial workup did not identify an etiology of his symptoms; however, he returned the following day with worsening pain and a radiology-performed ultrasound then revealed a segmental testicular infarct.

Discussion

Segmental testicular infarcts are a rare, often idiopathic, source of scrotal pain. Diagnosis is made by ultrasound, and repeat imaging may be required if not apparent on initial evaluation. Management is typically conservative although some require surgical intervention.

Fournier's gangrene mimicking an acute epididymitis

Fournier's gangrene is a urologic emergency secondary to a necrotizing soft tissue infection. Fournier's gangrene is characterized by severe pain and features of Fournier's gangrene may include edema, blisters and bullae, crepitus, subcutaneous gas, and systemic symptoms. Risk factors include male gender, alcohol abuse, immunocompromised state, uncontrolled diabetes mellitus, obesity, and malignancy. The diagnosis is made clinically but is often supported by radiography, ultrasound, computed tomography, and magnetic resonance imaging. Treatment consists of emergent hospitalization and surgery to debride the necrotic tissues. Morbidity and mortality for Fournier's gangrene are very high if left untreated. Early surgical intervention is key to the successful treatment of Fournier's gangrene. This case report presents a case of Fournier's gangrene mimicking acute epididymitis and highlights the importance of a thorough physical examination with high clinical suspicion for Fournier's gangrene.

When to ask for an MRI of the scrotum

Background

Multiparametric MRI (mpMRI) of the scrotum has been established as a useful second‐line diagnostic tool for the investigation of scrotal diseases. Recently, recommendations on clinical indications for scrotal MRI were issued by the Scrotal and Penile Imaging Working Group of the European Society of Urogenital Radiology.

Objective

To update current research on when to ask for an MRI of the scrotum.

Methods

PubMed database was searched for original articles and reviews published during 2010–2021.

Results

Eighty‐three articles fulfilled the search criteria. Scrotal MRI is mainly recommended after inconclusive US findings or inconsistent with the clinical examination and should be asked in the following cases: differentiation between intratesticular and paratesticular lesions (in rare cases of uncertain US findings), characterization of paratesticular and intratesticular lesions (when US findings are indeterminate), discrimination between germ cell and sex cord‐stromal testicular tumors, local staging of testicular malignancies (in patients planned for testis‐sparing surgery), differentiation between seminomas and non‐seminomatous tumors (when immediate chemotherapy is planned and orchiectomy is delayed), assessment of acute scrotum and scrotal trauma (rarely needed, in cases of non‐diagnostic US findings) and detection and localization of undescended testes (in cases of inconlusive US findings). Although preliminary data show promising results in the evaluation of male infertility, no established role for mpMRI still exists.

Conclusion

Multiparametric MRI of the scrotum, by assessing morphologic and functional data represents a valuable problem‐solving tool, helping to improve our understanding on the nature of scrotal pathology and the process of spermatogenesis. The technique may improve patient care and reduce the number of unnecessary surgical procedures.