The document summarizes a study investigating clinical and electroencephalography (EEG) features of patients with nonconvulsive status epilepticus (NCSE). The study reviewed 45 patients over 5 years. The most common etiologies were acute symptomatic (58%) and cerebrovascular disease (49%). EEG patterns were classified using the Salzburg Consensus Criteria, with 25 definite, 30 possible, and 6 no NCSE. In-hospital mortality was high at 33%. Prognostic factors associated with mortality included potentially fatal etiology, refractory NCSE, use of anesthetics, multiple EEG patterns, and nonreactive EEGs. The criteria had high diagnostic accuracy but did not affect prognosis.

1. ELECTROCLINICAL PATTERNS IN PATIENTS WITH
NONCONVULSIVE STATUS EPILEPTICUS :
ETIOLOGY, TREATMENT, AND OUTCOME
Presented by:
dr. Banu Eko Susanto
Supervised by:
dr. Diah Kurnia Mirawati, dr, Sp. S (K)
1

2. 2

3. ABSTRACT
3

4. ABSTRACT
 Introduction: This study investigated the clinical and electroencephalography (EEG)
features and prognostic factors of patients with nonconvulsive status epilepticus (NCSE).
 Materials and methods: retrospectively reviewed the clinical files and EEG data of 45
consecutive patients with NCSE over a five-year period.
 Results: The most common etiology for NCSE was acute symptomatic etiologies (57.8%)
and cerebrovascular disease (48.9%). Twenty-five status patterns on the EEGs were
classified as definite, 30 as possible, and six as no NCSE according to the SCC (Salzburg
Consensus Criteria). The in-hospital mortality rate was high (33.3%)
 Conclusions: The SCC for NCSE have high diagnostic accuracy but do not affect
prognosis.
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5. 1. INTRODUCTION
5

6. INTRODUCTION
 Nonconvulsive status epilepticus (NCSE) is an important cause of reduced or
altered levels of consciousness, which may worsen the prognosis of
neurologic outcomes.
 Electroencephalography (EEG) plays an essential role in identifying the
diagnosis of this condition.
 NCSE is a treatable disorder in most cases and probably underdiagnosed,
especially in critically ill patients.
 This research systematically assessed the demographic features, etiologies,
treatments, ictal EEG patterns, and prognostic findings in our patients
diagnosed as having NCSE
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7. 2. MATERIAL AND METHODS
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8. PATIENTS POPULATION AND DATA
COLLECTION
 Researcher retrospectively reviewed the clinical files and video-EEG recordings of all
consecutive adult and adolescent patients aged over 15 years who were diagnosed and
treated for NCSE at the Department of Neurology of the Trakya University Hospital
between January 2015 and July 2020.
 NCSE was defined as the occurrence of seizures without marked motor manifestations
lasting more than 10 minutes, which was confirmed through EEG recordings in all
patients
 The etiology of NCSE was grouped as stated in the International League Against
Epilepsy (ILAE) classification as acute, remote or progressive symptomatic
8

9. DIAGNOSIS OF NCSE
 Diagnosis of NCSE was made by a certified epileptologist with more than ten years’
experience for the patients who were referred to the EEG department with clinical
suspicion of NCSE.
 All patients referred to the EEG department had either altered consciousness without
major motor symptoms or persistence of altered consciousness after a motor seizure.
 Twenty-one channel EEG recordings with additional anterior temporal electrodes (FT9
and FT10) according to the international 10–20 system for at least a 30-minute duration
were recorded from each patient.
 Continuous EEG monitoring was not available for patients with SE, but routine EEGs
were repeated at different days in patients who were not responsive to antiseizure
treatments.
 Reevaluation of EEGs according to the SCC was performed by a certified clinical
neurophysiologist (LBK) who was trained on theSCC for NCSE.
9

10. DIAGNOSIS OF NCSE
 Status patterns in the EEGs were classified as ‘definite NCSE,’ ‘possible NCSE,’ or ‘no
NCSE’ according to the SCC
10

11. STATISTICAL ANALYSIS
 For categorical variables, Chi-square tests or Fischer’s exact test was used.
 Continuous variables were analyzed using independent Student t-tests or the Mann–
Whitney U test after testing for normal distribution of the data.
 The level of significance was set as p < 0.05. Statistical analysis was performed using
commercially available statistical software (IBM SPSS 22.0).
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12. 3. RESULTS
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13. 13

14. PATIENT DEMOGRAPHICS
 45 patients [28 females, 17 males, mean age 54 ± 22.5 (range, 15–89) years
 The reasons for requesting an EEG:
 altered state of consciousness or behavioral abnormalities: 21 (48.9%) patients
 prolonged impairment of consciousness after convulsive seizures: 14 (31.1%),
 confusional states with minor motor manifestations in 10 (22.2%) patients.
14

15. ETIOLOGIES
 An acute symptomatic etiology was present in 26 (57.8%) patients.
 Cerebrovascular disease in 22 (48.9%) patients
 Multiple etiologies in 15 (33.3%) patients.
 Acute post-anoxic in 1 patient
 Potentially fatal etiologies were determined in 17 (37.8%) patients.
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16. ETIOLOGIES
 Brain magnetic resonance imaging (MRI) was performed in 41 patients; the other four
patients had only brain computed tomography (CT).
 Bilateral tonic-clonic seizures evolved into NCSE in 14 (31.1%) patients, preceded by
NCSE in six (13.3%) patients.
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17. EEG FINDINGS
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18. EEG FINDINGS
Fig. 1. An example of multiple status pattern. The patient was a 56-year-old female with a diagnosis of primary central nervous
system lymphoma. She presented with altered consciousness and minor motor movements in the left arm. The EEG shows
lateralized periodic discharges over the right temporal region with a frequency of 0.4–0.9 Hz, and rhythmic theta frequency
discharges over the left temporal region with fluctuation. The patient was treated with I.V. diazepam, phenytoin, levetiracetam, and
anesthetics, and died during her follow-up in the ICU unit
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19. EEG FINDINGS
Fig. 2. a-b: An example of false-negative diagnosis according to the SCC for NCSE. The patient was a 70-year-old female who was
admitted with fluctuating consciousness and irritability. She was diagnosed as having meningioma in the left parietal region. The
EEG shows lateralized periodic discharges over the left parietal region with a frequency of 0.9–1.2 Hz; there was no fluctuation or
evolution and no significant change after I.V. diazepam administration. The patient regained consciousness after treatment with I.V.
phenytoin. The EEG six days later shows notable improvement with mild slowing on the left parietal region
19

20. EEG FINDINGS
Fig. 2. a-b: An example of false-negative diagnosis according to the SCC for NCSE. The patient was a 70-year-old female who was
admitted with fluctuating consciousness and irritability. She was diagnosed as having meningioma in the left parietal region. The
EEG shows lateralized periodic discharges over the left parietal region with a frequency of 0.9–1.2 Hz; there was no fluctuation or
evolution and no significant change after I.V. diazepam administration. The patient regained consciousness after treatment with I.V.
phenytoin. The EEG six days later shows notable improvement with mild slowing on the left parietal region
20

21. TREATMENT
 NCSE was treated most frequently with I.V. diazepam and/or second-line AEDs including
phenytoin, valproic acid, and levetiracetam in 29 (64.4%) patients.
 Twelve (26.7%) patients were treated with additional I.V. continuous anesthetics as third-
line treatment in the ICU.
 One patient with a history of hepatic encephalopathy, who was not treated with AEDs,
was transferred to the ICU due to coma and died.
 In one patient, treatment was unknown
21

22. OUTCOME
 Fifteen (33.3%) patients died during hospital follow-up. The leading etiologies of SE
among the deceased patients were cerebrovascular disease (35.8%), tumors (28.6%),
and systemic infections (21.4%).
 Only potentially fatal etiology, refractory SE, treatment with continuous I.V.
anesthetics, nonreactive EEGs, and multiple status patterns in the EEGs revealed
significant association with mortality.
 Classification of status patterns according to the SCC as definite or possible NCSE had
no impact on outcome (p > 0.05)
 The mean follow-up time of the patients who were discharged from hospital was 1.7 ±
1.7 (range, 0–5) years.
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23. OUTCOME 23

24. 4. DISCUSSION
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25. DISCUSSION
 The overall prognosis of our patients was poor, with a 33.3% in-hospital mortality rate.
Presumed fatal etiology, refractory SE, use of continuous I.V. anesthetics, multiple status
patterns in the EEGs, and nonreactivity in EEGs were related to mortality.
 NCSE is a heterogeneous group of disorders, provoked most commonly by acute
symptomatic etiologies (57.8%) and cerebrovascular disease (48.9%). In 33.3% of the
patients, the etiology was multifactorial, with metabolic or infectious abnormalities
triggering SE in an already injured brain.
 Only one patient with a previous history of epilepsy died during follow-up, suggesting
that epileptic activity had little impact on mortality
 The diagnosis of NCSE is challenging due to rhythmic and periodic patterns in EEG that
fall on the ictal-interictal continuum, rather than electrographic seizures, which results
in inter-rater discordance
25

26. DISCUSSION
 The SCC had no impact on prognosis. The primary purpose of the SCC was not to
interpret outcomes.
 Multiple status patterns in EEGs were independently associated with mortality, which
has not been reported before.
 Previous studies showed that critically ill patients with LPDs in the EEGs had higher
mortality, whereas patients with lateralized rhythmic activity had superior functional
outcome
 Limitation:
 retrospective collection of clinical data
 relatively small sample size
 did not use continuous EEG
 Classified by one neurophysiologist who was blinded to clinical and outcome data.
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27. 5. CONCLUSION
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28. CONCLUSION
 This study confirms the importance of etiology, the morphology of status patterns
and the reactivity in EEGs, and clinical factors for the prognosis of NCSE.
 The SCC are highly concordant for NCSE diagnosis but have no impact on
prognosis.
 EEG should be mandatory, especially for older patients with alterations of mental
status and acute symptomatic etiologies with comorbidities or after motor seizures
in the event of prolonged alterations of consciousness
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29. THANK YOU
29

30. SALZBURG CRITERIA
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31. 31

32. MODIFIED
SALZBURG CRITERIA
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33. 33

34. 34

35. 35

36. 36

37. KLASIFIKASI STATUS EPILEPTIKUS 37

38. ETIOLOGI NCSE 38

39. TATALAKSANA SE 39

40. TATALAKSANA NCSE 40

41. ALGORITMA DIAGNOSIS NCSE 41

42. PROGNOSIS SE
42

43. STESS (STATUS EPILEPTICUS
SEVERITY SCORE)
43
STESS 4 points predicted
patients with higher mortality risk

44. EMSE(epidemiology
-based mortality
score in status
epilepticus).
44
EMSE 79 points to predicted
patients with higher mortality risk.

45. GELOMBANG EEG 45

46. 46