Varicocele: Accurate Diagnosis with Scrotal Doppler Ultrasound

Dr. Segnini
Dec 30, 2025
3 min read

Dr. Segnini Scrotal varicocele ultrasound

The Venous Problem in the Scrotum Scrotal varicocele ultrasound

A varicocele is an abnormal dilation of the veins of the pampiniform plexus , the group of veins that drains blood from the testicles. It is similar to varicose veins in the legs, but occurs in the spermatic cord. It is the most common treatable cause of male infertility and can cause scrotal pain or a feeling of heaviness. Although it is sometimes palpable ("bag of worms"), scrotal Doppler ultrasound is the gold standard technique for confirming the diagnosis, quantifying its severity, assessing its impact on the testicle, and ruling out other pathologies.

Why is Doppler Ultrasound the Gold Standard?

This study combines the high resolution of ultrasound to visualize anatomy with the sensitivity of Doppler to assess blood flow, offering key advantages:

Objective Confirmation: Diagnoses non-palpable (subclinical) varicoceles, which may be relevant in fertility studies.
Precise Quantification: Allows measuring the diameter of the veins and evaluating reflux, establishing the severity.
Associated Testicular Evaluation: Detects atrophy (decrease in size) or changes in the echogenicity of the affected testicle.
Differential Diagnosis: Rule out other causes of scrotal mass or pain, such as tumors, cysts, or hernias.
Guided for Treatment: Can be used to guide percutaneous embolization procedures .

Key Ultrasound Findings: Structure and Flow

1. B-Mode Findings (Anatomical Imaging):

Dilated Veins: Visualization of anechoic (dark) and serpentine tubular structures in the spermatic cord, above and behind the testicle. They are most evident with the Valsalva maneuver .
Venous Diameter: The diameter of the largest veins is measured at rest and during Valsalva maneuver . A diameter > 2-3 mm is considered diagnostic.
Changes in the Ipsilateral Testicle : In chronic and severe cases, a decrease in size (atrophy) or a change in the echogenicity of the affected testicle may be observed.

2. Findings with Color and Spectral Doppler (Functional Evaluation):

This is the most important component to confirm pathological reflux.

Venous reflux with Valsalva maneuver : The definitive diagnostic finding. When the patient is asked to perform the Valsalva maneuver (straining), color Doppler shows retrograde flow (color inversion) filling the dilated veins. Spectral Doppler quantifies this, showing an increase in the duration and speed of the reflux .
Reflux Classification (According to Sarteschi / Dubin & Amelar):
- Grade 1: Reflux only during Valsalva .
- Grade 2: Spontaneous reflux that increases with Valsalva .
- Grade 3: Continuous spontaneous reflux, even at rest.

Exploration and Classification Protocol

The exam is systematic and comparative:

Resting Examination: Both testes, epididymides and spermatic cords are examined in B mode. The testes (volume) and the basal diameter of the veins are measured.
Dynamic Doppler Evaluation (Critical Point): The transducer is placed over the upper spermatic cord. The patient is asked to perform a sustained Valsalva maneuver while being observed with Color and Spectral Doppler . The duration and maximum speed of reflux are measured.
Classification: Anatomical (diameter) and functional (degree of reflux) findings are integrated to make a complete diagnosis (e.g., "Left varicocele grade 2, with veins of 3.8 mm and spontaneous reflux that increases with Valsalva . Ipsilateral testicle of normal volume").

Differential Diagnosis

Ultrasound allows us to distinguish a varicocele from other conditions:

Hydrocele: Accumulation of fluid around the testicle, not vascular structures.
Epididymal cyst: Anechoic rounded lesion , without internal flow or communication with the cord.
Testicular Tumor: Solid mass within the testicular parenchyma, usually with vascularization on Doppler .
Inguinoscrotal Hernia : Loops of intestine or fat descending into the scrotum, with visible peristalsis.

Conclusion: More than an Image, a Functional Study

Doppler ultrasound for varicocele goes beyond simple visualization. It is a dynamic hemodynamic study that answers crucial clinical questions: Is it present? Is it clinically significant? Is it damaging the testicle? It provides objective data (diameter, degree of reflux, testicular volume) that guide treatment decisions, especially in the context of infertility or pain. For the urologist or andrologist, it is an indispensable report for deciding between observation, embolization , or surgery ( varicocelectomy ), with the goal of preserving fertility and alleviating symptoms.