ULTRASOUND OF THE SCROTUM - Normal
The main components when assessing the scrotum with ultrasound are the Epididymis, testis ,pampiniform plexus , spermatic cord and groin. The spermatic cord also contains the testicular, cremasteric, and deferential arteries, pampiniform plexus, nerves, and lymphatics.
Probe position longitudinal Testis.
Normal Sagittal Image Testis.
Normal Sagittal image head of epididymis
PROTOCOL FOR ULTRASOUND OF THE SCROTUM
ROLE OF ULTRASOUND
Ultrasound is essentially used to investigate causes for:
- Which side?
- Dull or sharp?
- Constant or intermittent?
- Acute or chronic?
- Does it travel higher?
- Undescended testis
- H/O Trauma ,surgery or infection?
- Reduced Sperm count
- Infections (orchitis,prostatitis)
- Polycystic kidney disease
EQUIPMENT SELECTION AND TECHNIQUE
- Use of a high resolution probe (7-15MHZ) is essential when
assessing the internal structures of the scrotum.
- Low PRF and high gain colour / power / Doppler capabilities when
assessing vessels of a testis.
- Be prepared to change frequency output of probe (or probes) to
obtain accurate length measurements, an overview of pathology and anatomy
to each other and adequately assess deeper structures in the abdomen if
- Must make sure the patient as comfortable
- Not only is this to put the patient at ease but you will get more information out of him which will give you better clues as to what the diagnosis will be.
- Using a towel or the patients gown, tuck the penis up over the symphysis to help elevate and immobilise the scrotum.
- Use warm gel.
- Begin with a survey scan transversely down the scrotum to compare echogenicity of the testes.
- Scan each side independantly in both longitudinal and transverse planes.
- You may need to apply slight pressure to immobilise the testis as you scan. However, it is important to scan with minimal pressure to visualize fluid overlying the testis.
- Locate the epididymal head and follow in transverse down the body and tail.
- Assess both intra and extratesticular structures with power doppler.
- The Valsalva manoeuver or scanning in the upright position should be performed when evaluating for varicoceles or hernias.
- If a varicocele is identified, the scan should be extended to assess the testicular veins for the point of origin. Such as extratesticular masses that could be compressing the vein (eg pelviclymphadenopathy)
- If a hernia is suspected, click here for hernia scanning protocol
Extratesticular Lump or swelling
- Epididymitis, Orchitis or Epididymo-orchitis
- Epididymal Cysts
- Varicocele in the Pampiniform plexus
- Cryptorchidism or Maldescent
- Scrotal "Pearl"
- Microlithiasis (intratesticular)
Scrotal swelling with pain - 4 main causes:
- Torsion (20%)
- Infection/inflammation (75-80%)
- Strangulated Hernia
Torsion results in acute testicular infarction and eventually an atrophic testicle and constitutes a medical emergency. Quite often these patients will bypass the imaging department and go straight to theatre.
- epididymitis:torsion = 3:2 <20years
- epididymitis:torsion = 9:1 >20years
- Germ Cell Tumours
||For normal anatomy and scanning protocol
BASIC HARD COPY IMAGING
A scrotal series should include the following minimum images;
- Transverse image showing both testes for comparitive echogenicity
- Transverse images of each testis
- Maximum transverse measurement of each testis
- Longitudinal images of each testis
- Maximum longitudinal measurement of each testis
- Epididymis to include the head , body and tail (bilaterally)
- Vascularity of each testis with spectral trace
- Spermatic cord
- Document the normal anatomy. Any pathology found in 2 planes,
including measurements and any vascularity
- Groin for lymphadenopathy