Quantitative Computed Tomography (QCT)

CT of the lumbar spine used for measuring the density of the bone with a calibration phantom underneath the patient.

Drs. Aenor Sawyer and Thomas Link

Scout radiograph showing sections through the vertebral bodies which are used to measure the bone density. Radiograph also shows that all vertebral bodies are intact without fracture.

Thomas Lang, PhD

Thomas Link, MD, PhD

CT of the hip with a calibration phantom underneath the patient. From this image bone density of the hip is measured.

Pioneered at UCSF, quantitative computed tomography (QCT) is a test to measure bone mineral density (BMD). It is performed using a computed tomography (CT) scanner and results in a 3D image. Hip and lumbar spine are the most common choices for evaluation with QCT.

QCT is recommended for:

• Those at risk of osteopenia (low bone mass)
• People who are being treated for osteoporosis and need to be monitored
• Those receiving, or who will receive, steroid therapy
• People with hyperparathyroidism
• Those with vertebral abnormalities
• People who are either small or tall
• Patients with large body habitus
• Those that have degenerative spine disease – in particular men

Contraindications:

• Anyone who recently had a test that involved barium, iodine, or other contrast materials
• Women who are or may be pregnant

What are the advantages of QCT?

Many people who cannot undergo DXA testing for various reasons can safely have a QCT scan. QCT scans are safe and offer reliable BMD measurements for patients who have:

• Arthritis
• Scoliosis
• Disc space narrowing
• Spinal degenerative diseases
• Aortic calcification
• Osteophytes
• Obesity

QCT protocols are within the low-dose range, comparable to that of mammograms.

Advantages of QCT at UCSF

• Rigorous protocols ensure safety
• Results read by world-class physicians who are subspecialty experts
• High-quality, advanced equipment and techniques

Who performs QCT at UCSF?