One hundred years ago, when Alzheimer’s Disease (AD) was even more of a mystery than it is now, amyloid protein aggregates were described as black spots that showed up on brain slices after autopsy. These aggregates, commonly known as plaques, denote the telltale sign that a patient has AD. Until recently, these plaques could only be detected after death, but Dr. Daniel Skovronsky, creator of Avid Radiopharmaceuticals, may have a solution.
On July 11th, Dr. Skovronsky will present his latest findings at the international meeting of the Alzheimer’s Association in Honolulu. He has spent the last five years creating a fluorine radioactive dye to be used in positron emission tomography (PET) scans. The results of these PET scans are engineered to be so accurate that they can compete with brain autopsies, the only method currently available to determine whether a patient has AD.
The Food and Drug Administration (FDA) questioned Dr. Skovronsky about his fluorine-18 dye and whether the results of fluorine-18 PET scans compare to the definitive results of brain autopsies. Dr. Skovronsky recruited thirty-five patients in hospice with ranging levels of memory loss; all of these patients would receive a PET scan and would have their brains autopsied post-mortem. The results of each patient’s PET scan matched his or her autopsy results.
If approved by the FDA, Dr. Skovronsky’s work will lead to an increase in accuracy in the diagnosis of Alzheimer’s disease. Currently, 20% of patients diagnosed with AD are revealed to not have the disease when an autopsy is performed. With fluorine-18, Dr. Skovronsky has fine-tuned a method to detect amyloid plaques in the brain in a living patient, which is a feat within itself. Previously, the only way one could determine whether a patient had the disease or not was through autopsy – a posthumous procedure. Now, patients could have the chance to receive an accurate diagnosis while they are still alive and earlier in their lives.
In addition to simply detecting plaque, fluorine-18 will also aid in understanding the development of the disease, for plaques were found in patients deemed as healthy when they took memory tests. Currently, people who are not diagnosed with AD earlier in life will not receive treatment until the disease has developed more, and they will likely not receive any preventative medicine. With Dr. Skovronsky’s PET scans, doctors could diagnose the development of the disease earlier and administer preventative measures to slow down the development of the disease. Also, patients who are currently misdiagnosed with AD do not receive the correct treatments that they need for the diseases that are actually causing their memory loss or dementia, like depression.
The Vanishing Mind – Promise Seen for Detection of Alzheimer’s – NYTimes
The Alzheimer’s Disease Neuroimaging Initiative positron emission tomography core – Alzheimer’s Dement. 2010
In Vivo Imaging of Amyloid Deposition in Alzheimer Disease Using the Radioligand 18F-AV-45 (Flobetapir F 18) – The Journal of Nuclear Medicine