Abdominal Wall Hernias: Ultrasound Confirmation and Differential Diagnosis
- Dr. Segnini
- Jan 12
- 2 min read
Beyond Physical Exploration
Abdominal wall hernias are protrusions of abdominal contents through a defect or area of weakness in the abdominal wall. Although many are clinically evident, dynamic ultrasound has become the preferred initial imaging technique for doubtful, complex, or atypically painful cases. Its main advantage is the ability to assess in real time and during exertion maneuvers.
The Added Value of Dynamic Ultrasound:
Confirmation of Diagnosis: Directly visualize the wall defect (hernial orifice), the hernial sac and its contents ( preperitoneal fat or omentum, intestinal loops).
Dynamic Characterization: Allows for the evaluation of changes during Valsalva maneuvers (coughing, straining) and with relaxation. This is crucial for reducible or intermittent hernias.
Differential Diagnosis: Distinguishes a hernia from other abdominal wall masses such as lipomas, hematomas, seromas , tumors ( desmoid ) or eventrations.
Evaluation of Complications: Identify signs of incarceration (non-reducible contents) or strangulation (vascular compromise: thickening of the intestinal wall, free fluid, absence of peristalsis ).
Intraoperative Guide : In laparoscopic repair techniques, it can help to pre-mark hernia defects.
Protocol and Key Ultrasound Findings by Hernia Type:
The examination is performed with a high-frequency linear transducer (7-12 MHz or more), in supine and standing positions, and always including stress maneuvers.
A) Findings Common to All Hernias:
Wall Defect: Interruption of the continuity of the aponeurotic/muscular layers.
Hernial sac: A structure that protrudes through the defect. On Doppler ultrasound , it may show vascularization.
Contents: Preperitoneal fat ( hyperechoic ) or intestinal loop (tubular structure with peristalsis and a "target" pattern in cross-section). The greater omentum is usually echogenic and non-peristaltic.
B) Characteristics by Location:
Inguinal Hernia (Indirect and Direct):
Indirect: The sac emerges through the internal inguinal ring, lateral to the inferior epigastric vessels, and may descend into the scrotum. Its path is followed towards the spermatic cord.
Direct: It protrudes through the posterior wall of the inguinal canal, medial to the inferior epigastric vessels. The sac is usually wider and shorter.
Femoral Hernia: The sac is visible below the inguinal ligament, medial to the femoral vein. More common in women.
Umbilical and Paraumbilical Hernia : A midline defect at or adjacent to the navel. Very common.
Linea Alba (Epigastric) Hernia: Small defect in the midline, between the umbilicus and the xiphoid process, usually containing only preperitoneal fat .
Incisional Hernia : Located in a previous surgical scar. They are usually complex, with multiple defects and adhesions.
Limitations and Considerations:
Operator-dependent and patient-dependent in performing the Valsalva maneuver .
Visualization can be difficult in obese patients or those with a lot of gas in the hernia contents.
For deep, complex hernias or advanced surgical planning, it can be complemented with Computed Tomography (CT).
Conclusion:
Dynamic ultrasound is an accurate, rapid, and cost-effective extension of the physical examination for the diagnosis of abdominal wall hernias. Its ability to confirm the presence of a hernia, characterize its contents, assess its reducibility , and rule out acute complications makes it an indispensable tool in general surgery, digestive surgery, and emergency departments, optimizing therapeutic decision-making.
Abdominal hernia ultrasound
Dr. Jose Segnini, Radiologist / Diagnostic Medical Sonographer
MD Radiologist (Venezuela – Chile)
Board Certified Diagnostic Medical Sonographer (ARDMS, USA)
Mobile Ultrasound & Medical Supplies – Orlando, Florida
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