Which Imaging Test Is Best for Hernia Diagnosis?

Each year, hundreds of hernia cases are diagnosed in Singapore; however, a significant number likely remain undiagnosed due to subtle symptoms or inconclusive physical findings. The signs can be small and easy to miss, and sometimes even doctors have a hard time identifying them just by looking or feeling.

Therefore, it is important to understand when imaging becomes essential for hernia diagnosis and which tests work best for different situations.

When Is Imaging Needed for Hernia Diagnosis?

Most hernias do not require imaging for diagnosis. An experienced hernia surgeon can often identify hernias through careful physical examination, particularly when patients present with classic symptoms and visible bulging. However, clinical examination has limitations and may need advanced technology for diagnosis.

These types of hernias make imaging necessary:

• Occult Hernias: This type causes symptoms without visible signs. Athletes frequently develop these "hidden" hernias, experiencing persistent groin pain that limits performance.
• Recurrent Hernias: After having surgery to fix a hernia, some people may need detailed scans to check the area again. Sometimes a new hernia can form, or there could be issues where the repair was done.

What Are the Different Types of Imaging Tests?

There are three primary imaging tests for hernia diagnosis: ultrasound, CT scan, and MRI. Each technique offers unique advantages and limitations, and understanding how these technologies work helps patients to feel more secure about the decision and during their diagnosis process.

Ultrasound

Ultrasound uses high-frequency sound waves to make a real-time image of what is happening inside the body. The procedure typically takes 15 to 30 minutes.

Pros:

• This procedure makes ultrasound the safest option for pregnant women, children, and patients requiring repeated studies.
• Patients may be able to use MediSave for ultrasound scans at approved centres.
• There is a real-time interpretation during the examination.

Cons:

• Accuracy can vary depending on hernia complexity and the quality of imaging.
• Limited penetration in obese patients can obscure deep structures, reducing diagnostic confidence in larger individuals.
• Interference from bowel loops can block visualisation of abdominal wall defects, particularly in patients with bloating or recent meals.

CT Scan (Computed Tomography)

CT scans combine X-ray technology with computer processing to generate more comprehensive cross-sectional images. The examination usually takes 10 to 20 minutes, during which patients lie on a table that moves through a scanner. In many cases, an injection of contrast dye is used to highlight certain areas and improve visibility.

Pros:

• Can identify small hernias, assess hernia contents, and evaluate surrounding structures simultaneously.
• Widely available in both public and private hospitals, enabling immediate evaluation of suspected complications.
• Follows standardised imaging protocols, which help provide consistent and reliable results across different healthcare settings.

Cons:

• Uses ionising radiation, which may pose a risk with repeated exposure
• Often more expensive than ultrasounds.
• Contrast reactions can occur in susceptible patients, ranging from mild nausea to severe allergic responses.

MRI (Magnetic Resonance Imaging)

MRI uses strong magnetic fields and radio waves to produce detailed images of internal structures. It is especially useful for soft tissue diagnosis, such as a hernia. The procedure typically lasts for about 30 to 60 minutes.

Pros:

• Offers a comprehensive three-dimensional view of the hernia anatomy.
• Uses magnetic fields instead of radiation, making it a safer choice for frequent imaging.
• Excels at differentiating tissue types and identifying subtle anatomical variations.

Cons:

• The most expensive imaging option.
• Patients with metallic implants may not be suitable for MRI scans.
• Lengthier examination times.

What Are the Factors to Consider Before Choosing the Right Imaging Test?

Selecting the optimal imaging study requires careful consideration of multiple factors. Smart diagnostic strategies balance accuracy, safety, cost, and practical considerations.

Based on Hernia Type

The best imaging technique for diagnosing a hernia often depends on its type and location:

• Groin Hernias (Inguinal, Femoral): These often begin with an ultrasound. If the diagnosis remains unclear, an MRI or CT scan may follow.
• Abdominal Wall Hernias (Umbilical, Ventral, Incisional, Lumbar): Ultrasound may be sufficient for simple cases, but CT scans are often preferred for a more detailed view of the abdominal wall and surrounding tissues.
• Deep Pelvic Hernias (Obturator, Sciatic, Perineal): These rare hernias are located deep within the pelvis and often present with vague symptoms. MRI or CT scans are typically needed for accurate diagnosis.
• Hiatal Hernias: Depending on the patient’s symptoms and clinical suspicion, imaging options may include a CT scan, MRI, or a barium swallow to assess the stomach and oesophagus.

Based on Patient Factors

The choice of imaging for a hernia can also be tailored to individual patient factors:

• Pregnancy: For pregnant patients, ultrasound is often the only safe and effective imaging option due to its lack of radiation exposure.
• Body Weight: Obese patients may require CT or MRI imaging due to the extra layers of soft tissue.
• Urgency (Emergency vs. Elective): In emergencies, CT scanning is often used in A&E departments for rapid evaluation due to its speed and availability.

Consult a Trusted Clinic for Your Hernia Imaging Test

Imaging effectively complements a careful clinical evaluation. The combination of a thorough medical history, physical examination, and appropriately selected imaging studies forms the foundation for accurate hernia diagnosis and optimal treatment planning. Always consult a qualified hernia surgeon, who can determine whether imaging is appropriate and help guide the most suitable next steps.

If you are considering an imaging test for your hernia, call us at 6262 1226 to schedule a consultation.