Pseudoseizures After Epilepsy Surgery

Pseudoseizures After Epilepsy Surgery E. W.

LOIS FRANK

M.D., TERESA A. RUMMANS, M.D. SHARBROUGH, M.D., SHEILA G. JOWSEY, M.D. GREG D. CASCINO, M.D. KRAHN,

Seizure surgery for medically intractable partial epilepsy in selected patients usually results in dramatically improved seizure control. However, the authors present six patients who, after surgery for refractory complex partial seizures, postoperatively experienced pseudoseizures (also known as nonepileptic seizures), confirmed with EEG monitoring. Three of these patients also had nonepileptic seizures preoperatively that coexisted with their partial epilepsy. Psychiatric assessment revealed that this patient group had several characteristics in common, which suggests that preoperative psychiatric consultation may help identify those patients at risk for developing nonepileptic seizures. Treatment strategies with anticonvulsant medications and behavioral therapy (Psychosomatics 1995; 36:487-493) are reviewed.

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seudoseizures or nonepileptic seizures have been reported to occur in conjunction with documented partial epilepsy.· Distinguishing between the two in some patients is difficult, but patients who develop nonepileptic seizures tend to have several common characteristics, including unusual and often dramatic seizure behavior and a past psychiatric history. 2 Prolonged video electroencephalogram (EEG) has aided in this endeavor. When patients are discovered to have both types of problems, treatment has been primarily aimed at controlling the epileptic seizures. Anticonvulsant medications and in refractory cases seizure surgery are two therapeutic modalities used for epilepsy patients. It is known that anticonvulsant treatment for epileptic seizures has little effect on the pseudoseizures, but no reports exist of the effect of surgery on this phenomenon. Also, nothing is known about the person who develops nonepileptic seizures postoperatively. We describe the diagnosis and management of six patients who had temporal or frontal VOLUME 36. NUMBER 5. SEPTEMBER - OCTOBER 1995

lobectomies for medically intractable partial epilepsy and later developed postoperative nonepileptic seizures. Neurosurgical treatment has become increasingly common for the treatment of medically intractable partial epilepsy. Results vary from institution to institution but on average seizures are eliminated in 50% and significantly improved in an additional 25% of patients. 3 Coexisting epileptic and nonepileptic seizures are not an absolute contraindication for epilepsy surgery; however, the patient must meet several criteria for consideration as a surgical candidate. At our institution, these include focal epileptiform spikes and sharp waves that lateralize to one area in which there is a low risk of operative neurologic morbidity; clinical seizures, based on history and video that correlate Received March 31. 1993; revised May 21, 1993; accepted August 12. 1993. From the Departments of Psychiatry. Psychology and Neurology. Mayo Clinic. Rochester. MN. Address reprint requests to Dr. Rummans. Adult Psychiatry. Mayo Clinic. Rochester. MN 55905. Copyright © 1995 The Academy of Psychosomatic Medicine. 487

Pseudoseizures After Epilepsy Surgery

with electrographic findings; a clinical examination. psychometric testing. magnetic resonance imaging scan. angiogram. and amytal testing consistent. or at least not contradictory. to the EEG findings; and finally patients with adequate motivation. emotional stability. and intelligence. so they can be expected to benefit from the procedure. METHODS Seizure surgery began at our institution in the 1950s and more than 700 patients have had neurosurgery for medically intractable seizure disorders in the last 10 years. Using a database established in 1976. we reviewed the diagnoses of all patients 18 and older who had seizure disorders. neurosurgery. and nonepileptic seizures (which may have also been referred to as pseudoseizures or conversion disorders). We reviewed the medical records of these patients and excluded those patients whose nonepileptic seizures were present only before neurosurgery or whose nonepileptic seizures were not confirmed by EEG monitoring. The data collected include several clinical features: sex; age; duration of epilepsy; fullscale IQ (FSIQ) ; neurosurgical procedure performed; preoperative psychiatric history; preoperative history of seizures. including anticonvulsant medications in use before preoperative epilepsy monitoring; postoperative psychiatric history; epileptic seizure outcome. including anticonvulsant medications at the time of psychiatric intervention; nonepileptic seizure outcome and treatment; and follow-up data. The diagnosis of nonepileptic seizures. whether preoperative or postoperative. was accepted only if the chart indicated that the patient experienced a spell during EEG monitoring. Epileptic seizure outcome was determined based on the neurologists' postoperative assessment usually done 3 months after surgery. FSIQ was measured in the course of routine preoperative psychometric testing. The psychiatric history was obtained by treating psychiatrists who interviewed patients. reviewed outside records. and when possible interviewed family mem488

bers. Psychiatric diagnoses were made in clinical interviews with DSM-III-R criteria. After postoperative nonepileptic seizures were confirmed with EEG monitoring. all six patients were hospitalized on an inpatient psychiatric unit. where the postoperative psychiatric assessment was done and treatment was initiated. Follow-up information was available when the patient returned for a later neurologic or psychiatric visit. RESULTS The patients on average had a long duration of epilepsy. ranging from 18 to 41 years. Table I summarizes preoperative and postoperative seizure history and anticonvulsant use immediately before surgery and at the time they received psychiatric intervention for their nonepileptic seizures. The patients' psychiatric diagnoses and type of psychiatric intervention are also reported. The group was evenly composed of men and women; mean age was 30. The FSIQ was determined during the preoperative evaluation. and the mean was 78. well below average for adults. All of the patients in this series did fairly well as far as remission ofepileptic seizures was concerned. Postoperatively. all patients remained on therapeutic doses of anticonvulsant medications. Three patients (C. D. and E) were believed to experience ongoing but markedly less frequent postoperative epileptic seizures. Epileptic seizures were thought eliminated in the other three patients. Treatment plans for the postoperative nonepileptic seizures included behavioral therapy for all six patients. In addition to their anticonvulsant medications. two patients also received pharmacotherapy for coexisting psychiatric disorders. Follow-up information was available for only one patient. DISCUSSION Distinguishing complex partial seizures from nonepileptic events has always been challenging. Prolonged EEG monitoring has allowed clinicians to monitor patients over an extended PSYCHOSOMATICS

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TABLE 1. Patient data

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Patient! Age (years)1 Gender (MIF)I Age at Onset

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Preop Seizure History and Treatment

Postop Psychiatric Diagnosis and Treatment

Nonepileptlc Seizure Outcome Aller Psychiatric Intervention and Follow-up

Full-Scale IQ

A 261F16

68

LTL

History of adjustment 0/0, treated with INPT supportive psychotherapy

Frequent CPS on Cmand Pb; confirmed NES no treatment

No CPS on Py and Pb, ongoingNES

Somatoform 0/0 NOS,INPT behavioral therapy recommended

Unknown, patient went home for outpatient behavioral therapy, no follow-up

8 211F13

74

LTL

Intermittent explosive 0/0, borderline personality 0/0, no treatment

Frequent CPS on Va and Cz; confirmed NES, no treatment

No CPS on Py, Pb,and Va; ongoing NES

Intermittent explosive 0/0, borderline personality 0/0, ? malingering, treated with INPT behavioral therapy

NoNES, no follow-up

C 21IMI3

84

LTL

History of conversion 0/0 treated with INPT behavioral therapy

Frequent CPS on Cm and Pb; confirmed NES treated with INPT behavioral therapy

No CPS on Py andCm, ongoing NES

Conversion 0/0, INPT behavioral therapy attempted

Ongoing NES, patient refused psychiatric treatment, no follow-up

044003

73

RFL

Alcohol abuse in Frequent CPS on full remission, Va and Cm; confirmed NES, organic mental 0/0 NOS (postictal) no treatment psychosis); treated with multiple brief courses of antipsychotic medications

Rare nocturnal CPS on Py and Cm when levels low, ongoing NES

Organic mental 0/0 NOS, treated with antipsychotic medication and INPT behavioral therapy

No NES, 28 months follow-up after psychiatric treatment

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Preop Psychiatric Diagnosis and Treatment

Neurosurgical Procedure

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Postop Seizure Outcome

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(continued)

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TABLE 1.

PatientJ Ale (years)1 Gender (MIF)I Ale at Onset E361M115

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Patient data (continued)

Full-Scale IQ

Neurosurgical Procedure

94

LTL

76

LTL

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Preop Psychiatric Diagnosis and Treatment

Preop Seizure History and Treatment

Postop Seizure Outcome

Postop Psychiatric Diagnosis and Treatment

Somatofonn pain 0/0, history of depression treated with antidepressant medication and INPT supportive psychotherapy

Frequent CPS on Pi; suspected NES, no treatment

Rare CPS on Cmand Pi, NES

Somatofonn 0/0 NOS,INPT behavioral therapy

None

Frequent CPS on Cm and Cz; no known NES

Note: LTL = left temporallobeetomy; 0/0 = disorder; CPS seizures; Py = phenytoin; NOS = not otherwise specified; INPT lobectomy; Pi = primidone

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Nonepileptic Seizure Outcome After Psychiatric Intervention and Follow-up Ongoing NES no follow-up

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Rare CPS on Py, Anxiety 010 CM and Pb, NES NOS, treated with Czand INPT behavioral therapy

NoNES, no follow-up

= complex partial seizures; Cm = carbamazepine; Pb = phenobarbital; NES = nonepileptic = inpatient psychiatric treatment; Va = valproic acid; Cz = c1onazepam; RFL = right frontal

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Krahn et al.

time period and increase the likelihood of recording a typical event on tape, permitting comparison with a simultaneously recorded EEG. When seizure activity correlates with no epileptiform activity on EEG, the diagnosis of nonepileptic seizures is entertained. This diagnosis should be restricted to patients with objective ictal movements or unresponsiveness, because patients who report only a subjective complaint of impaired consciousness may be experiencing a simple partial seizure, otherwise known as an aura, where no corresponding EEG abnormalities would be present. 4 The absence of scalp-recorded EEG alterations during partial seizures has been reported; however, this phenomenon has usually been described with simple partial seizures. There is no published data about the false negative rate of surface EEG recordings (Sharbrough FW, personal communication, 1993). Only two of our patients (D and E) were monitored preoperatively with depth electrodes, which confirmed the coexistence of seizure foci and nonepileptic seizures. Because of the increased risks of implanting depth electrodes, these are rarely used, and nonepileptic are distinguished from epileptic seizures by using surface electrodes, with the knowledge that a very small percentage of seizures may be missed with this technique. s All monitoring has limitations, because it cannot be used to definitively rule out epileptic or nonepileptic seizures; however, monitoring can help in the diagnosis, because a videotaped clinical seizure with corresponding epileptogenic discharges strongly points to an epileptic event, and likewise an unusual atypical spell without corresponding findings suggests a nonepileptic event. In this report, we described six patients who experienced nonepileptic seizures after seizure surgery. Because of its retrospective nature, we were not able to determine the prevalence of postoperative nonepileptic seizures. Because patients were not assessed in a systematic fashion for postoperative nonepileptic seizures and not every patient with possible nonepileptic seizures underwent postoperative ambulatory EEG monitoring, we expect that the VOLUME 36. NUMBER 5. SEPTEMBER - OCTOBER 1995

prevalence is higher than this study implies. Psychiatric assessment revealed that these six patients shared several characteristics. Most of these patients experienced epilepsy from early childhood and would not remember a time when they were free of frequent seizures. Recent studies have shown that patients with early onset ofepilepsy in conjunction with hippocampal atrophy tolerate surgery.6 However, these same patients face a major adjustment when they experience a reduction in seizures postoperatively. They often have an identity as an "epileptic," which to varying degrees has affected their relationships and activities up to the time of surgery.7 They predictably welcomed a reduction in seizure frequency, but when they had a good outcome, they faced increased expectations of functioning better socially and occupationally. Furthermore, the patients in our series tended to have relatively low IQs, inadequate coping strategies, and poor social skills. Patients could be easily overwhelmed by change and need an outlet, conceivably leading to the emergence of nonepileptic seizures. As seen in Table I, the six patients had a variety of preoperative and postoperative psychiatric diagnoses. According to DSM-III-R, nonepileptic seizures are most frequently part of a conversion disorder, although they may also be associated with other psychiatric disorders. Episodes under conscious control are indicative of factitious disorders or malingering. s At least one of patient B's nonepileptic seizures appears to have been under voluntary control, because during this prolonged episode, she was seated in front of the nursing station, experiencing a typical nonepileptic seizure, and requesting a room change. Apart from this example, these patients appeared not to have conscious control, which classifies these events as conversion symptoms. When schizophrenia, anxiety disorders, affective disorders, and somatization disorders coexist with conversion symptoms, these disorders are the primary diagnosis and require appropriate intervention.9 Patient F was treated for anxiety associated with nonepileptic seizures at one point. When he was reevaluated I year later, 491

Pseudoseizures After Epilepsy Surgery

the nonepileptic seizures appeared to occur in isolation. The primary psychiatric diagnosis of Patient D, who experienced nonepileptic seizures associated with confusion and delusional thinking, remains unclear. His preoperative postictal psychosis is consistent with a history of seizure-related delirium, but postoperatively his symptoms did not appear associated with seizures. Nonepileptic seizures are fairly commonly encountered conversion symptoms, entities that occur when patients cannot directly express distress and instead communicate emotional pain in tenns of physical complaints. IO,1I Preoperatively, three patients in this series (A, B, and D) had a confinned history of nonepileptic seizures, which was strongly suspected but undocumented in a fourth patient (E). Patients with a propensity to experience conversion symptoms like nonepileptic seizures are also prone to develop other somatofonn disorders. 12 Patient E had been preoperatively diagnosed and treated for a somatofonn pain disorder. Postoperatively, in addition to experiencing nonepileptic seizures, three patients (A, C, and E) had other somatic complaints revealing their tendency to somatize. Somatic symptoms serve many potential purposes for patients, including a method of communication, secondary gain, conflict resolution, depressive equivalent, manifestation of anxiety, or expression of hostility.13 Somatic symptoms postoperatively also necessitate ongoing contact with medical professionals, on whom these patients had been dependent in the past. Previously, their intractable epilepsy demanded that their lives revolve around medical appointments, anticonvulsant blood levels, and diagnostic tests. With their seizure disorder in better control, these patients require less medical attention, potentially a difficult adjustment for patients with dependency needs. Little has been written about how to treat patients with coexisting epileptic and nonepileptic seizures. Anticonvulsant medications are necessary to treat the documented seizure disorder. Titrating the medications is more difficult, because seizure frequency as reported by 492

the patient usually reflects both epileptic and nonepileptic seizures. When anticonvulsant medications are increased to reduce overall seizure frequency, the patient is at higher risk for side effects, particularly sedation. Nonepileptic seizures may be aggravated with anticonvulsant toxicity because of disinhibition. 14 Identifying the seizures that are nonepileptic and aiding the patient and family to recognize the frequency of nonepileptic and epileptic seizure frequency separately may avoid excessive use of anticonvulsant medication. Because of their relatively limited intellectual abilities, patients for the most part were not appropriate candidates for insight-oriented therapy. However, the patients did benefit from supportive psychotherapy examining the impact their epilepsy had on their life and how their roles have changed as a result of improved seizure control after surgery.2 In our series, three clearly benefited, and one may have responded positively but was lost to follow-up. These patients were well suited for behavioral therapy which can address learning new and more effective coping styles,lS In particular, social skills training can be beneficial when patients are deficient in this area. Family involvement is crucial, because often patients have received a lot of attention and assistance from family members or caretakers because of their epilepsy, and now these persons must also make appropriate adjustments, Provided that the patient is physically safe, family members must prevent reinforcing nonepileptic seizures by ignoring the event and actively praising the patient's progress and independence. CONCLUSION This study raises two important issues about selection of candidates for seizure surgery. Should preoperative nonepileptic seizures be an absolute contraindication to seizure surgery and must patients with nonepileptic seizures that coexist with their epileptic seizures receive preoperative psychiatric intervention? Our conclusions are limited by a paucity of followup data, but it appeared that at least one patient with PSYCHOSOMATICS

Krahn et al.

pre-operative nonepileptic seizures had an excellent postoperative outcome as far as seizure frequency was concerned. This suggests that preoperative nonepileptic seizures should not be an absolute contraindication for seizure surgery. In response to the second issue, there is also limited data. Because only one patient received preoperative treatment for nonepileptic seizures, recommendations about preoperative psychiatric treatment for nonepileptic seizures cannot be developed based on this case series. However, it seems reasonable to offer behavioral treatment to appropriate motivated patients before surgery, because improved coping skills will likely help them deal with the stress of neurosurgery and could be expected to reduce the likelihood of postoperative nonepileptic seizures. We are reluctant to require successful psychiatric treatment before considering a patient for surgery, because frequent

epileptic seizures and medication side effects may interfere with a person's ability to engage in behavioral therapy. Postoperatively, we believe that all patients with nonepileptic seizures should be offered appropriate treatment. Even if nonepileptic seizures are not entirely eradicated postoperatively, it appears that reduction in frequency of epileptic seizures still can represent improved level of functioning and quality of life. Complex partial seizures and nonepileptic seizures are known to coexist, and their coexistence should not be an absolute contraindication to seizure surgery. Psychiatric evaluation can identify factors that place persons at higher risk of having nonepileptic seizures so that appropriate support and therapy can be made available. In doing so, patients with coexisting epileptic and nonepileptic seizures can experience both a reduction in overall seizure frequency and improved quality of life.

References I. Remick RA, Wada JA: Complex partial and pseudoseizure disorders. Am J Psychiatry 1979; 136:32~323 2. Trimble MR: Pseudoseizures. Neurol Clin 1986; 4:531548 3. Uematsu S: Surgical management of complex partial seizures. JAMA 1990; 264:734-737 4. Meierkord H. Will B. Fish D, et al: The clinical features and prognosis of pseudoseizures diagnosed using videoEEG telemetry. Neurology 1991; 41:1643-1646 5. King DW. Gallagher BB. Murvin AJ. et al: Pseudoseizures: diagnostic evaluation. Neurology 1982; 32: 1821 6. Trenerry MR. Jack CR. Sharbrough FW. et al: Relationship between MRI hippocampal volumes. age-of-onset and verbal memory change following temporal lobectomy (abstract). Epilepsia 1992; 33(suppl 3): 121 7. Hermann BP. Whitman S: Behavioral and personality correlates of epilepsy: a review. methodological critique and conceptual model. Psychol Bull 1984; 95:451~97

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8. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders. 3rd Edition. Washington. DC. American Psychiatric Association. 1980 9. Lazare A: Current concepts in psychiatry: conversion symptoms. N Eng J Med 1978; 305:745-748 10. Ford CV: The somatizing disorders. Psychosomatics 1986; 27:327-337 II. Schofield A. Duane MMA: Neurologic referrals to a consultation-liaison service: a study of 199 patients. Gen Hosp Psychiatry 1987; 9:28~286 12. Folks DO. Ford CV, Regan WM: Conversion symptoms in a general hospital. Psychosomatics 1984; 25:285-295 13. Kellner R: Somatization: theories and research. J Nerv MentDis 1990; 178:15~160 14. Niedermeyer E, Blumer D. Holscher E. et al: Classical hysterical seizures facilitated by anticonvulsant toxicity. Psychiatrica Clinica 1970; 3:71-84 15. Massey EW. Riley TL: Pseudoseizures: recognition and treatment. Psychosomatics 1980; 21 :987-997

493