From the Research
To optimize peripheral nerve imaging in patients with morbid obesity, use high-frequency ultrasound (12-18 MHz) with lower frequency probes (5-10 MHz) for deeper structures, and increase the depth setting to 4-6 cm, as this approach has been shown to be effective in overcoming the challenges posed by increased subcutaneous tissue 1. When imaging peripheral nerves in patients with morbid obesity, several challenges arise, including greater signal attenuation and depth-related artifacts, making it more difficult to visualize the nerves 2. Some key considerations for optimizing peripheral nerve imaging in this patient population include:
- Using high-frequency ultrasound probes for superficial structures and lower frequency probes for deeper structures
- Increasing the depth setting to 4-6 cm to accommodate the increased subcutaneous tissue
- Positioning patients carefully to minimize tissue compression
- Using liberal acoustic coupling gel to improve contact between the probe and the skin
- Adapting MRI protocols to use larger coils, increase the field of view, and adjust for higher signal-to-noise ratio, as well as utilizing fat suppression techniques like STIR or Dixon methods 3, 4. It is also important to consider patient preparation, including instructing patients to remain still during imaging, considering mild sedation if necessary, and using positioning aids like wedges and supports for comfort 5. By using these techniques, clinicians can help overcome the challenges related to increased subcutaneous tissue and improve the visualization of peripheral nerves in patients with morbid obesity. Some of the key challenges in imaging obese patients include the physical limitations of ultrasound technology, which can make it difficult to visualize very low-lying nerves 4. However, with the right approach and techniques, clinicians can optimize peripheral nerve imaging in patients with morbid obesity and improve patient outcomes. The use of open permanent magnets or other specialized equipment may also be necessary in some cases to accommodate patients with extreme obesity 5. Overall, a careful and tailored approach is necessary to optimize peripheral nerve imaging in patients with morbid obesity.