Medical Isotopes Used in SPECT and PET Imaging

**Chapter 1**

**Abstract**

Single-Photon Emission

Radiopharmaceuticals

Computed Tomography (SPECT)

Nuclear medicine techniques have a great deal of advantage of using gamma radiation emitter radiolabeled compounds to diagnose the long list of infectious and malignant disorders in human systems. The gamma emitter radionuclide-labeled compounds are associated with single photon emission computed tomography (SPECT) camera. SPECT camera mainly offers the detection and analysis of gamma rays origin to furnish the imaging of defective organs in the body. There are about 85% radiopharmaceuticals in clinical practice which are being detected by SPECT camera. The following chapter is an update about the SPECT radiopharmaceuticals

Nuclear medicine technique (NMT) is a detection process that helps in obtaining diagnostic results at molecular level of a disease. The technique is carried out by administrating target-specific radioisotope-labeled organic/biomolecule to patient and collecting the gamma signals through scintillating camera to diagnose the infected organ/tissues. In contrast to advanced instrumental procedures such as magnetic resonance imaging (MRI) and computed tomography (CT) scan, NMT offers a wide range of detection limit. For example, NMT starts working from molecular level when no morphological changes appear; however MRI and CT do

NMT works by administration of radiolabeled molecules (commonly known as radiopharmaceuticals) to patients and acquisition of radiation collected through scintillation camera. There are two main components of radiopharmaceuticals: the organic/biomolecule and the radioisotope. The former approaches diseased cells/ tissues and accumulate there at diseased cells and the latter part emits radiation to

Diagnosis through NMT means the image of internal body organs like heart, kidney, lungs, breast, brain, bones, tissues, or whole body using γ-emitting radiopharmaceuticals; for example, indium-111 (111In) and technetium-99m (99mTc) labeled molecules. These radionuclides are labeled with a variety of compounds including drugs, organic species, peptides, proteins, and antibodies and then

*Syed Ali Raza Naqvi and Muhammad Babar Imran*

that were developed and tried for infection and cancer diagnosis.

nuclear medicines, infection imaging

indicate the position of diseased area.

**1. Introduction**

**3**

**Keywords:** 99mTc-antibiotics, SPECT imaging, radiopharmaceuticals,

this job at the appearance of morphological changes in diseased tissues.
