Michael C. Johnson – Neuroimaging in Ophthalmology

Автор: Michael C. Johnson
Название книги: Neuroimaging in Ophthalmology
Формат: PDF
Жанр: Нейроофтальмология
Качество: Изначально компьютерное, E-book

Neuroimaging and orbital imaging using computed tomography (CT) and magnetic
resonance imaging (MRI) techniques have revolutionized the evaluation, management,
and treatment of orbital and neuro-ophthalmic disorders. Despite the
increased resolution of these imaging studies, it is critical for the diagnosing clinician/
ordering physician and the interpreting radiologist to communicate with
one another clearly and explicitly about the relevant topographical anatomy, to
confi rm the localizing value of the clinical fi ndings, to generate a compatible differential
diagnosis, and, most important, to correlate the clinical fi ndings with the
radiographic fi ndings (i.e., “clinical correlation required”).
It is our hope that this revision of the original AAO neuroimaging monograph
will assist clinicians in understanding the mechanics of the imaging techniques
(i.e., CT and MRI), the indications and contraindications for specifi c imaging,
and the clinicoradiologic correlation of specifi c neuro-ophthalmic or orbital
presentations.
The authors of the current edition wish to acknowledge and thank the authors
of the fi rst edition (Dr. Eric Berman, Dr. Jonathan Wirtschafter,* and Dr. Carolyn
Johnson) for their work, which served as the basis for this revision. We would also
like to acknowledge Dr. Daniel Thedens, PhD, for his work in reviewing the physics
section of this monograph.
We have tried to update, rather than completely replace, the content of the original
version, especially in the areas of neuroimaging that have not changed signifi –
cantly over time. To update the monograph, a literature review was performed by
the current authors using a systematic English-language MEDLINE search (1994–
2008) limited to articles with relevance to neuro-ophthalmic and orbital imaging
The new information in this monograph includes the following: 1) an update on
the basic mechanics, indications, and contraindications for cranial and orbital CT
and MRI, 2) the indications and contraindications for intravenous contrast (e.g.,
iodinated contrast for CT and gadolinium contrast for MRI), and 3) the basics
of specifi c MR sequences and specifi c techniques (e.g., CT/MR angiography and
venography). Because of space limitations, detailed discussion of the functional
imaging techniques such as functional MRI (fMRI), positron emission tomography
(PET) scanning, and single-photon emission computed tomography (SPECT)
are not included in this monograph.
In the original version of this monograph, Chapter 1 provided a nonmathematical
introduction to the physics of imaging. We have tried to simplify this portion of
the original text and provide a more concise and clinically meaningful context for
the basics of the imaging techniques for the targeted audience of this monograph.
The basic physics for the imaging studies might help the reader better understand
CT and MRI such that studies are ordered and interpreted more precisely and effi –
ciently. Chapters 1 through 3 are intended to provide a basic framework for the
normal and pathologic radiologic fi ndings seen in various disease entities of interest
to the ophthalmologist. Chapter 4, the last section of the monograph, provides
the reader with guidelines for ordering the proper imaging study and provides specifi
c pathologic examples of interest to the ophthalmologist.