Baylor University Medical Center Proceedings July 2017 - 362

Usefulness of positron emission tomography to detect
cerebral amyloid as a means to diagnose
neurodegenerative disease
Jessica Page, MD, Umesh Oza, MD, Kennith Layton, MD, and Claudia Padilla, MD

Alzheimer's disease is characterized
histologically by the accumulation of
a subtype of amyloid protein-beta
amyloid-in the brain parenchyma
in the form of amyloid plaques. In
another neurodegenerative disorder,
cerebral amyloid angiopathy, the accumulation of beta amyloid occurs
within the walls of the cerebral vessels. With recent advances in imaging
technology, we can not only image
amyloid plaques in the brain paren- Figure 1. Several susceptibility-weighted MR images through the brain depict the widespread foci of hemosiderin staining
chyma at an earlier stage of disease, (arrows) from chronic microhemorrhages, characteristic of cerebral amyloid angiopathy.
but can also often correlate the presence of Alzheimer's disease with cerebral amyloid angiopathy. We present
tion found him to have an intermediate probability of having
AD. Brain magnetic resonance imaging (MRI) disclosed many
a case of suspected Alzheimer's disease and discuss the association
punctate foci of signal dropout in a widespread distribution on
in this patient between cerebral amyloid angiopathy and Alzheimer's
susceptibility-weighted images (Figure 1), correlating with the
disease, as well as the benefits of a unique nuclear imaging modality,
presence of many chronic microhemorrhages.
amyloid positron emission tomography, in diagnosing dementia.

ementia is characterized by a progressive deterioration
in multiple neurological functions, including memory, thinking, behavior, and ability to perform daily
tasks. The number of people living with dementia was
estimated at 47.5 million in 2015 and is expected to reach
75.6 million by 2030 (1). Currently, the cost burden related to
dementia is estimated at US $604 billion, and this will likely
increase exponentially over the next few decades (1). If experimental therapies to remove or reduce the production of amyloid
in the brain can be shown to be eﬀective, early detection of Alzheimer's disease (AD) and other dementias could be important
in terms of slowing progression of the disease. In recent years, a
nuclear imaging technique has been developed that utilizes one
of several similar radiotracers, including Amyvid (Florbetapir
F-18), to selectively highlight and image amyloid plaques, which
are abundant in the brains of patients with AD.
CASE REPORT
A 68-year-old man presented for progressive memory loss
over the past 2 years. A detailed neuropsychological evalua362

The patient also participated in the Imaging Dementia-
Evidence for Amyloid Scanning (IDEAS) study, which examines how brain imaging, speciﬁcally amyloid positron emission
tomography (PET) scan, can assist clinicians in diagnosing
and treating AD and other dementias. As opposed to a normal
amyloid scan (Figure 2a, 2b), the patient's scan demonstrated
a widespread abnormal increase in radiotracer accumulation
within the cortical gray matter resulting in loss of gray-white
matter distinction (Figure 2c, 2d).
DISCUSSION
Until recently, imaging had a limited role in the diagnosis
of dementia. The primary means of diagnosing AD is currently
neuropsychological evaluation utilizing a set of clinical criteria,
a method that is neither sensitive nor speciﬁc. Recent advances,
From the Department of Radiology (Page, Oza, Layton) and the Division of
Neurology, Department of Internal Medicine (Padilla), Baylor University Medical
Center, Dallas, Texas.
Corresponding author: Jessica Page, MD, Department of Radiology, Baylor
University Medical Center, 3500 Gaston Avenue, Dallas, TX 75246 (e-mail:
Jessica.Page@bswhealth.org).
Proc (Bayl Univ Med Cent) 2017;30(3):362-364

Table of Contents for the Digital Edition of Baylor University Medical Center Proceedings July 2017