Florbetaben F18 is a18F-labeled stilbene derivative used as a tracer for PET imaging of beta-amyloid deposits in the human brain. The F 18 isotope produces a positron signal that is detected by a PET scanner. 3H-florbetaben in vitro binding experiments reveal two binding sites (Kd of 16 nM and 135 nM) in frontal cortex homogenates from patients with AD. Binding of florbetaben F18 to beta-amyloid plaques in post-mortem brain sections from patients with AD using autoradiography correlates with both immunohistochemical and Bielschowsky silver stains. Florbetaben F 18 does not bind to tau or alpha-synuclein in tissue from patients with AD. Neither Neuraceq nor non-radioactive florbetaben F 19 bind to AT8 positive tau deposits in brain tissue from patients with frontotemporal dementia (FTD), using autoradiography and immunohistochemistry, respectively.

Flutemetamol F 18 is a radioactive molecular agent that is intended for use with PET imaging of the brain in adults being evaluated for Alzheimer's disease (AD) and dementia. Flutemetamol F 18 consists of flutemetamol, a thioflavin derivative of Pittsburgh compound B (PiB) labeled with the radioisotope fluorine F18 and it selectively binds to cerebral fibrillar beta-amyloid, a peptide involved in Alzheimer's disease.

Florbetapir (18F) (trade name AMYViD; also known as florbetapir-fluorine-18 or 18F-AV-45) is a PET scanning radiopharmaceutical compound containing the radionuclide fluorine-18, recently FDA approved as a diagnostic tool for Alzheimer's disease. Florbetapir, like Pittsburgh compound B (PiB), binds to beta-amyloid, however fluorine-18 has a half-life of 110 minutes, in contrast to PiB's radioactive half life of 20 minutes. Wong et al. found that the longer life allowed the tracer to accumulate significantly more in the brains of people with AD, particularly in the regions known to be associated with beta-amyloid deposits. A negative Amyvid scan indicates sparse to no neuritic plaques, and is inconsistent with a neuropathological diagnosis of AD at the time of image acquisition; a negative scan result reduces the likelihood that a patient’s cognitive impairment is due to AD. A positive Amyvid scan indicates moderate to frequent amyloid neuritic plaques; neuropathological examination has shown this amount of amyloid neuritic plaque is present in patients with AD, but may also be present in patients with other types of neurologic conditions as well as older people with normal cognition. Amyvidis an adjunct to other diagnostic evaluations

Ioflupane I-123 (trade name DaTscan) is a radioiodinated cocaine analogue synthesized from a key starting material Sn FP-CT via oxidative iododestannylation with sodium (123I)-iodide. Ioflupane I-123 binds reversibly with high affinity to the dopamine transporter (DaT) protein, a marker for presynaptic terminals in dopaminergic nigrostriatal neurons. It has been developed as a dopamine transporter imaging agent for single photon emission computed tomography (SPECT) which is claimed to be sensitive enough to differentiate changes in the nigrostriatal dopaminergic system in patients with Parkinsonism and healthy controls. DaTSCAN is unable to discriminate between Parkinson's Disease, Multiple System Atrophy and Progressive Supranuclear Palsy. DaTscan is an adjunct to other diagnostic evaluations. Headache, nausea, vertigo, dry mouth, or dizziness of mild to moderate severity as well as hypersensitivity reactions and injection-site pain have been reported. The DaTscan injection may contain up to 6% of free iodide (iodine 123 or I-123). To decrease thyroid accumulation of I-123, the thyroid gland has to be blocked at least one hour before administration of DaTscan because of the long-term risk for thyroid neoplasia. DaTscan was first approved in the European Union (EU) on July 27, 2000. It is also approved in Israel, Switzerland and in the United States (a total of 33 countries).

Technetium Tc 99m Bicisate is a Radioactive Diagnostic Agent indicated as an adjunct to conventional computed tomography (CT) or magnetic resonance imaging (MRI) in the localization of stroke in patients in whom stroke has already been diagnosed. Technetium Tc 99m Bicisate is a lipophilic complex with high first-pass extraction fraction and deposition and retention in the brain in proportion to cerebral blood flow. Its radionuclide emissions permit external imaging of the cerebral distribution of the agent, thus allowing the detection of altered regional cerebral perfusion. The retention in the brain of technetium Tc 99m Bicisate results from in vivo metabolism (de-esterification) of the primary complex to polar, less diffusable compounds Technetium Tc-99m Bicisate is metabolized by endogenous enzymes to the mono- and di-acids of Technetium Tc-99m Bicisate that can be detected in blood and urine. Technetium Tc-99m Bicisate is excreted primarily through the kidneys. Within two hours, 50% of the injected dose is excreted and by 24 hours, 74% is found in urine.

Iofetamine hydrochloride I-123 is a radiopharmaceutical for cerebral perfusion imaging. lofetamine is the N-isopropyl derivative of amphetamine with iodine 123(1123) at the para position to serve as the tracer. This configuration was systematically derived by Winchell et al. to provide sufficient brain uptake and retention for brain imaging, which typically requires an acquisition time of 25-40 minutes. After experimental intraarterial injection the drug has a high extraction ratio (> 90 percent) in the brain. Iofetamine hydrochloride I-123 permits cerebral blood perfusion imaging with single photon emission computed tomography (SPECT). Iofetamine is an amphetamine analog that is rapidly taken up by the lungs, then redistributed principally to the liver and brain. The precise mechanism of localization has not been determined, but is believed to result from nonspecific receptor binding. Brain uptake peaks at 30 minutes postinjection and remains relatively constant through 60 minutes. The drug is metabolized and excreted in the urine, with negligible activity remaining at 48 hours. When compared with CT in stroke patients, visualization may be performed sooner after symptom onset and a larger zone of involvement may be evident with iofetamine. Localization of seizure foci and diagnosis of Alzheimer's disease may also be possible. As CT has revolutionized noninvasive imaging of brain anatomy, SPECT with iofetamine permits routine cerebral blood flow imaging. Iofetamine hydrochloride I-123 under the brand name Spectamine was approved for use in the United States as a diagnostic aid in determining the localization of and in the evaluation of non-lacunar stroke and complex partial seizures, as well as in the early diagnosis of Alzheimer's disease in 1987. However it was discontinued in USA.

Iometopane (RTI-55, beta-CIT) is a cocaine congener, binding to the neuronal dopamine and serotonin reuptake transporters affinity of Kd = 0.3 nM. Radiopharmaceutical forms of RTI-55 are used in single-photon emission computer tomography. Radioisotops 123I and 125I are favored, but 124I also used as a positron emitter to diagnose Parkinson's Disease.

IOLOPRIDE I-123 (also known as I-123 iodobenzamide), a radioactive drug that can be seen by Single-photon emission computed tomography. This drug binds to the some dopamine receptors and can be used in the neonatal period. It shows the biochemical maturation of D2 receptors and also manifests the deleterious effect of perinatal hypoxic-ischemic events on D2 receptors.

Indium In-111 pentetate disodium is a radioactive diagnostic indicated for use in radionuclide cisternography. Decay of In-111 by electron capture allows for detection with a gamma camera for visualization of the brain and spinal column. Indium In 111 pentetate ( 111In-DTPA) is indicated as an imaging agent in cisternography to study the flow of cerebrospinal fluid (CSF) in the brain, to diagnose abnormalities in CSF circulation, to assess and help localize the site of CSF leakage, and to test the patency of or localize blocks in CSF shunts.

Molybdenum-99 (99Mo, half-life = 66 h) is a parent radionuclide of a diagnostic nuclear isotope. It decays in technetium-99 m (half-life = 6 h), which is used in over 30 million procedures per year around the world. Between 95 and 98 percent of Mo-99 is currently being produced using highly enriched uranium (HEU) targets. Other medical isotopes such as iodine-131 (I-131) and xenon-133 (Xe-133) are by-products of the Mo-99 production process and will be sufficiently available if Mo-99 is available.