June 16, 2008 - From the top of the head to the soles of the feet, molecular imaging is a vital element of today's medical practice, adding an extra dimension to diagnosis and disease management that can change the way common and devastating diseases are understood and treated.
"Molecular imaging is making major scientific contributions by improving health care through prevention, diagnosis, treatment planning, treatment monitoring and disease recurrence assessment. These are the ‘big five' functions of molecular imaging," said Henry N. Wagner Jr., SNM past president and professor at Johns Hopkins University Bloomberg School of Public Health, who annually selects the SNM Image of the Year from thousands presented at the Annual Meeting.
This year, two images were jointly selected as the 2008 SNM Image of the Year. One image reveals a relapse of neuroendocrine cancer—a malignancy of the interface between the hormonal and nervous systems—including a nodal involvement. The second image illustrates the exact extent and location of an infection in the foot.
These two images were united not only to demonstrate the breadth and depth of molecular imaging but also to show that imaging techniques are increasingly being used in combination to provide precise snapshots of both the molecular function and the anatomy of disease in various parts of the human body.
"Using positron emission tomography and computed tomography (PET/CT), one group of physicians was able to see that a suspicious lesion in the left ear was not confined just to that area, but also involved a lymph node. This helped them plan the subsequent treatment," added Dr. Wagner. "The image of the foot shows that single photon emission computed tomography with magnetic resonance imaging (SPECT/MRI) is being used just as successfully as PET/CT. In this one, the fused image shows clearly that the patient has not only a soft tissue infection but also osteomyelitis—or infection of bone or bone marrow."
The first image comes from a case of a neuroendocrine tumor located in the left middle ear that was referred for restaging. "The patient was a young male treated by surgery a few months before," said Stefano Fanti, professor of nuclear medicine at the Policlinico S. Orsola–Università di Bologna in Italy. "Conventional imaging, including CT and MR, showed a suspect local relapse. PET/CT confirmed the local relapse, but also demonstrated a nodal involvement, leading to an alteration of his treatment. The finding was subsequently confirmed by CT, and the patient was scheduled for systemic treatment."
The second image reveals an abnormal cellular process in the infected foot of a diabetic patient. "MRI provides almost perfect images of anatomy and bony structure changes, but it may exaggerate the extent of infection," said Karin Knesaurek, associate professor in the department of radiology and nuclear medicine at Mount Sinai Medical School. "SPECT imaging is more accurate for infection localization but lacks anatomical reference. By combining these, we were able to determine the exact extent and location of the disease, and the patient underwent selective excision of the second metatarsal head only, preserving the rest of her foot."
Dr. Fanti and Dr. Knesaurek presented their work at the SNM 55th Annual Meeting, "Molecular Imaging: Build on the Past, Define the Future," which was attended by thousands of molecular imaging scientists and technologists. The meeting showcased molecular imaging's ability to provide a portrait of what's going on in a patient's body, providing useful information to help shape treatment plans, often eliminating the need for exploratory surgery and providing a painless and safe alternative for diagnosing and treating patients. It also allows doctors to see how effective a treatment is early in the process, so that it can be immediately adjusted.
"These images represent the present state-of-the-art and show that molecular imaging modalities such as SPECT and PET are here to stay," said Dr. Wagner.
Posters: S. Fanti, P. Castellucci, V. Ambrosini, P. Tomassetti, G. Montini, V. Allegri, D. Rubello, C. Nanni, R. Franchi, Nuclear Medicine, Azienda Ospedialiero-Universitaria di Bologna, Bologna, Italy, "Restaging of Neuroendocrine Tumor Imaged with 68GA-DOTA-NOC PET-CT." K. Knesaurek, J. Machac, M. Muzinic, M. DaCosta, Z. Zhang, B. Mocherla, S. Heiba, Department of Radiology/Nuclear Medicine; D. Kolker, Department of Orthopedics; and S. Vatti, Department of Radiology/MSK all at Mount Sinai Medical School, New York, N.Y. "Fusion of In-111 WBC SPECT/CT and MRI in a Diabetic Patient With an Infected Foot," SNM 55th Annual Meeting, June 14–18, 2008.
For more information: www.snm.org