In the past few decades, ambulatory EEG has evolved from its inception as a novelty of clinical neurophysiology engineering to its current mature form as a routine clinical test ordered at local laboratories by neurologists worldwide. The rapid pace at which the technology, availability, and clinical utility of ambulatory EEG have advanced during this time has required electroencephalographers to keep up with the capabilities of this recording technique at an impressive rate.
Over this same time period the clinical neurophysiology world, of which ambulatory EEG is just one part, has been transformed. The development of specialized epilepsy centers has revolutionized the diagnosis and management of seizure disorders and brought focus to the need for prolonged EEG recording of high quality. In particular, the advent of epilepsy surgery as a major treatment option for some patients with medically refractory seizures has propelled the field of EEG monitoring forward. In addition, the increasing recognition of disorders that mimic epilepsy, including both psychogenic nonepileptic seizures (PNES) and physiological paroxysmal episodes that are nonepileptic, has also widened the spectrum of patients for whom EEG monitoring is appropriate.
However, financial and other constraints have affected the clinical use of neurophysiological studies to a significant degree. Physicians who are planning long hospitalizations for inpatient EEG recording must face the pressures of decreasing reimbursement, hospital space constraints, and patient dissatisfaction with in-hospital care. As the acuity of most hospitalized patients rises, so does the disparity between the typical neurology inpatient and the elective EEG-monitoring patient who has infrequent spells that may or may not be epileptic seizures.
Ambulatory EEG thus occupies an important niche in the clinical neurophysiology laboratory. Many patients who require prolonged EEG recording with event detection algorithms need not be admitted to the hospital; in fact both doctor and patient may prefer recording at home for convenience, the ability to capture events in the patient’s natural environment, and the avoidance of inpatient nosocomial infection risk, among many other factors. The assumed sacrifice in recording quality that accompanied ambulatory EEG in its early days is now generally minimal or nonexistent, and the full extent of video recording and associated physiological parameter monitoring is now available on an ambulatory basis at many centers.
In this context, the clinical utility of an atlas of ambulatory EEG is clear. Although the principles of EEG interpretation remain unchanged regardless of recording environment, we believe that the ability of an electroencephalographer to review instructive examples of both normal and abnormal EEG activity recorded on an ambulatory basis will be significantly beneficial. Reference examples of common artifacts seen on ambulatory EEG and ictal events recorded using ambulatory systems may be particularly useful.
The three chapters in this book help to set the stage for the collection of ambulatory EEG excerpts and annotations presented later.
- In Chapter 1, John Ives and Don Schomer relate a brief history of ambulatory EEG technology from its inception to the present.
- Chapter 2, by K. Babu Krishnamurthy, describes the event-detection algorithms — both spike and seizure detection — that have facilitated the widespread use and interpretation of ambulatory EEG.
- Finally, in Chapter 3, Frank Drislane discusses the clinical role of ambulatory EEG in modern day epilepsy practice.
This book will serve as a useful reference for a wide range of clinical neurophysiology practitioners, from trainees to experienced EEG readers, as well as for EEG technologists and others involved in the development and application of EEG recording software and hardware. After 30 years, countless innovations, and thousands of patient studies, ambulatory EEG now has its own atlas.
Contents
- Introduction
Chapter 1 A Brief History of Ambulatory EEG
- Introduction
- The Rationale for Ambulatory Monitoring
- Continuous versus Event/Intermittent Recording
- Clinical Application
- Summary
Chapter 2 Automated Spike and Seizure Detection Algorithms
- Introduction
- Automatic Spike Detection
- Seizure Detection
- Conclusion
Chapter 3 The Clinical Use of Ambulatory EEG
- Purposes of EEG Monitoring
- Event Monitoring
- Ambulatory EEG Monitoring
- Practical and Technical Considerations
The Atlas
Technical Aspects
- Technical 1. A Typical Screen or Printed Page of Ambulatory EEG Recording
- Technical 2. Left Temporal Seizure: No Filter Used
- Technical 3. Left Temporal Seizure: 60-Hz Notch Filter
- Technical 4. Left Temporal Seizure: High Frequency 35-Hz Filter
- Technical 5. Left Temporal Seizure: High Frequency 15-Hz Filter
- Technical 6. Generalized Spike-Wave Activity: Paper Speed 30 Seconds Per Page
- Technical 7. Generalized Spike-Wave Activity: Paper Speed 15 Seconds Per Page
- Technical 8. Generalized Spike-Wave Activity: Gain = 2
- Technical 9. Generalized Spike-Wave Activity: Gain = 1
Normal Sleep Morphologies
- Normal Sleep 1. Sleep Spindles
- Normal Sleep 2. K-Complexes and Sleep Spindles Recorded by Spike Detection Algorithm
- Normal Sleep 3. Rapid Eye Movement of Sleep
Ambulatory Artifacts
- Artifacts 1. Horizontal Eye Movement and Blink Artifacts
- Artifacts 2. Eye-Blink Artifact
- Artifacts 3. Eye Flutter Artifact Recorded by Seizure Detection Algorithm
- Artifacts 4. Electrode Tapping Artifact
- Artifacts 5. Jaw-Clenching Artifact
- Artifacts 6. Chewing Artifact
- Artifacts 7. Chewing Artifact Recorded by Spike Detection Algorithm
- Artifacts 8. Dry Electrode Artifact
- Artifacts 9. Forehead Rubbing Artifact
- Artifacts 10. Pulse Artifact
Abnormal Epileptiform Activity
- Epileptiform 1. Focal Mesial Temporal Spikes Recorded by Spike Detection Algorithm
- Epileptiform 2. Focal Anterior Temporal Spikes Recorded by Spike Detection Algorithm
- Epileptiform 3. Bifrontal Spike-Wave Complexes Recorded by Spike Detection Algorithm
- Epileptiform 4. Rolandic Spikes
- Epileptiform 5. Three-Per-Second Spike-and-Wave Activity Recorded by Spike Detection Algorithm 86
- Epileptiform 6. Generalized Spike-and-Wave Activity Recorded by Seizure Detection Algorithm
- Epileptiform 7. Brief Generalized Spike-and-Wave Activity Recorded by Seizure Detection Algorithm
- Epileptiform 8. Left Frontotemporal Seizure Recorded by Pushbutton Activation
- Epileptiform 9. Frontal Onset Epileptiform Activity Recorded by Seizure Detection Algorithm
- Epileptiform 10. Right Mesial Temporal Seizure Recorded by Pushbutton Activation
- Epileptiform 11. Frontal Seizure Recorded by Pushbutton Activation 104
Index
Book Details
- Paperback: 120 pages
- Publisher: Academic Press (August 1, 2005)
- Language: English
- ISBN-10: 0126213453
- ISBN-13: 978-0126213454
- Product Dimensions: 11.3 x 8.4 x 0.5 inches
List Price: $94.95