Lumbar disc disease
In symptomatic cases the diagnosis should be confirmed by an MRI scan. However, in cases with slight symptoms, a faster and cheaper CT scan (although it is inferior to MRI scan) may be recommended. While a CT scan can show the bony structures in more detail, an MRI scan can better portray soft tissue.
Medical ultrasound
Sonography is effective for imaging soft tissues of the body. Superficial structures such as muscle, tendon, testis, breast, thyroid and parathyroid glands, and the neonatal brain are imaged at a higher frequency (7–18 MHz), which provides better linear (axial) and horizontal (lateral) resolution. Deeper structures such as liver and kidney are imaged at a lower frequency 1–6 MHz with lower axial and lateral resolution as a price of deeper tissue penetration.