ABSTRACT
Two percent of patients with traumatic brain injury (TBI) experience early seizures, de ned as occurring while the patient is still experiencing the direct effects of the head injury, usually within the rst 24 hours of injury, although up to 2 weeks later in those with severe head trauma.1 There is a 3.6-fold increase in late seizures (after the acute effects of head trauma have resolved). The majority of these late-occurring seizures take place during the rst year following TBI, although some increased risk continues for 4 years after the trauma. By de nition, the occurrence of multiple seizures (two or more) is de ned as epilepsy. Although epilepsy (i.e., late-occurring seizures) has long been recognized as a common sequel to brain injury, progress in understanding the pathophysiology and treatment of posttraumatic epilepsy has been limited. Therefore, clinicians have little information regarding appropriate therapy of posttraumatic epilepsy, and as a result, therapy of posttraumatic epilepsy has remained empirical and arbitrary. The decision to initiate or withhold antiepileptic drug (AED) therapy has far-reaching implications for rehabilitation of the traumatic brain-injured patient. Inappropriate use of anticonvulsants may cause unnecessary cognitive impairment in those persons not requiring medication. At the same time, experimental data suggest that certain types of seizures may retard functional improvement during recovery from brain injury, whereas other types have no deleterious
CONTENTS
2.1 Introduction ........................................................................................................................ 29 2.2 Evaluation of Episodic Behavioral Changes ..................................................................30 2.3 Clinical Evaluation of Seizures ........................................................................................ 31 2.4 Etiologic Considerations ...................................................................................................33 2.5 Diagnostic Investigations of Posttraumatic Seizures ...................................................35 2.6 Potential Epileptogenesis Associated with Psychotropic Medications ......................36 2.7 Therapy for Posttraumatic Epilepsy ................................................................................ 37 2.8 Mechanisms and Models of Posttraumatic Epilepsy ...................................................42 2.9 Posttraumatic Seizures, Epilepsy, and Anticonvulsant Prophylaxis:
Implications for Neurobehavioral Recovery ..................................................................46 2.10 Conclusions ......................................................................................................................... 51 References ....................................................................................................................................... 52
consequences. Thus, it is crucial to differentiate patients who will require and bene t from AED therapy from those who will not.
