Diagnostic Ultrasound - Abdomen and Pelvis

Groin Hernia
Diagnoses: Abdominal Wall/Peritoneal Cavity
○ Scan medially for superficial ring and look for direct
inguinal hernia
○ At each area, examine at rest and during Valsalva
maneuver for presence of hernia or laxity
○ Examine other side if hernia found, examine sites of
tenderness
○ Cine clips strongly advised
○ Repeat with patient standing, more sensitive for fluid in
hernia
DIFFERENTIAL DIAGNOSIS
Lipoma of Spermatic Cord
• No change with Valsalva maneuver, not reducible
• Usually no deep extension into peritoneal cavity
Encysted Hydrocele Canal of Nück
• Processus vaginalis extends from peritoneal cavity to
scrotum in embryo
○ Normally obliterates in cord while scrotal component
persists as tunica vaginalis
○ Failure of obliteration leads to fluid distension within
cord, known as encysted hydrocele canal of Nück
– Filled with anechoic fluid, no change with Valsalva
maneuver, not reducible
– No deep extension into peritoneal cavity
Inguinal Canal Lesions
• Benign and malignant tumors: Neurofibroma, desmoid,
metastases, lymphadenopathy, lymphoma, sarcomas
• Undescended testis
• Miscellaneous: Varicocele, abscess, hematoma, granuloma,
scar
PATHOLOGY
General Features
• Etiology
○ Multifactorial
– Chronic: Increased intraabdominal pressure from
abdominal distension (ascites)
□ Weak abdominal musculature: Chronic cough,
prostatism, constipation, manual labor, pregnancy,
steroids, collagen abnormality, smoking
– Acute: Sudden severe increase in intraabdominal
pressure
○ Indirect inguinal hernia: Congenital due to persistence of
processus vaginalis in infants and children
Gross Pathologic & Surgical Features
• Sac contents: Commonly omentum, ascites, small bowel, or
mobile colon segments (sigmoid, cecum, appendix), rarely
bladder, ovary
○ Littre hernia: Meckel diverticulum in sac
○ Richter hernia: Only portion of bowel circumference
(antimesenteric portion) in sac
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Groin lump or discomfort with positive cough impulse
(allows clinical diagnosis)
– Continuous or intermittent
• Other signs/symptoms
○ Features of intestinal obstruction
Demographics
• Age
○ Indirect inguinal hernia tend to occur in young to middleaged
individuals
○ Prevalence of direct inguinal hernia increases with
increasing age
○ Femoral hernia is more common in middle-aged to
elderly individuals
• Gender
○ Indirect inguinal hernia is 5-10x more common in males
○ Direct inguinal hernia nearly always occurs in males
○ Femoral hernia is more common in females
– However, indirect inguinal hernia is most common
hernia in females
• Epidemiology
○ Hernia repair is most common surgical procedure in US
○ 5% of males develop groin hernia
○ 75% of all hernias inguinal, indirect to direct 5:1
○ 10-15% femoral
○ Inguinal hernia in children is always result of patent
processus vaginalis and is thus indirect hernia extending
to scrotal sac
Natural History & Prognosis
• Recurrence rate after repair: 1-15%
○ Direct inguinal hernia may develop after repair of
indirect inguinal hernia
• Complications: Obstruction, strangulation
○ Indirect inguinal hernias account for 15% of intestinal
obstruction cases
○ Obstruction or strangulation more common with
femoral hernias due to narrow neck
Treatment
• Laparoscopic or open hernia repair
DIAGNOSTIC CHECKLIST
Consider
• Relation of hernia neck to inferior epigastric artery for
inguinal hernias
• Femoral hernia: Below inguinal ligament
SELECTED REFERENCES
1. Arend CF: Static and dynamic sonography for diagnosis of abdominal wall
hernias. J Ultrasound Med. 32(7):1251-9, 2013
2. Jain N et al: Ultrasound of the abdominal wall: what lies beneath? Clin Radiol.
68(1):85-93, 2013
3. Robinson A et al: Meta-analysis of sonography in the diagnosis of inguinal
hernias. J Ultrasound Med. 32(2):339-46, 2013
4. Stavros AT et al: Dynamic ultrasound of hernias of the groin and anterior
abdominal wall. Ultrasound Q. 26(3):135-69, 2010
5. Bhosale PR et al: The inguinal canal: anatomy and imaging features of
common and uncommon masses. Radiographics. 28(3):819-35; quiz 913,
2008
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