Seizure patient selection for emergency computed tomography

doi:10.1016/S0196-0644(05)80111-8

Annals of Emergency Medicine

Volume 22, Issue 8, August 1993, Pages 1298-1303

https://doi.org/10.1016/S0196-0644(05)80111-8 Get rights and content

Study purpose:

We evaluated the need for emergency non-contrast cranial computed tomography (CT) among patients presenting to an emergency department with a complaint of seizure.

Methods:

We retrospectively evaluated the medical records of 115 consecutive patients who presented to a trauma Level I ED with a complaint of seizure and underwent a noncontrast cranial CT.

Results:

Sixty patients had a known seizure disorder, 38 had new-onset seizure, and 17 had possible seizure. The results of the neurologic examination and CT could be compared in 105 of the patients. An abnormal neurologic examination predicted 19 of 20 positive CT scans (95%) and demonstrated a strong association with CT results (P < .00004). Only a history of malignancy correlated to CT findings (P < .008). No other catalogued variable showed a statistical relationship with CT findings.

Conclusion:

Our data suggest that patients with either a history of malignancy or an abnormal neurologic examination at the time of examination in the ED will derive the greatest benefit from emergency CT.

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Cited by (34)

First-Time Seizure Patients have High Rate of Abnormalities on Emergency Department Performed Brain Computed Tomography: A Prospective Study
2023, Journal of Emergency Medicine
First-time seizures comprise 15% to 35% of all seizure-related complaints in the emergency department (ED). Emergent neuroimaging of first-time seizure patients is recommended by both the American Academy of Neurology and American College of Emergency Physicians. However, most of these studies are over 10 years old and included both adults and children.
The goal of this investigation is to determine the rate of abnormal neuroimaging in adults with first-time seizures presenting to the ED during the current era.
This was a prospective observational study of patients presenting to three urban EDs with a chief complaint of seizure over 18 months. Abnormal neuroimaging findings were defined a priori and were dichotomized into acute and subacute/chronic categories.
Of the 2505 patients who presented with a seizure, 242 patients (9.7%) presented with a first-time seizure. The most common etiologies for first-time seizures were drug intoxication and drug withdrawal. Of those 242 patients, 29 (11.9%) patients had abnormal findings on brain computed tomography (CT). Brain CT demonstrated an acute finding in 13 (45%) patients and a subacute/chronic finding in 16 (55%) patients. The most common abnormality overall and the most common chronic finding was ischemic changes. The most common acute findings were traumatic intracranial hemorrhage and intracranial metastases.
This study demonstrated that 11.9% of first-time seizure patients presenting to the ED had abnormal findings on neuroimaging. Our findings support current recommendations to obtain emergent neuroimaging for adult patients with first-time seizures.
ACR Appropriateness Criteria® Seizures-Child
2021, Journal of the American College of Radiology
Citation Excerpt :
It is important to note that distinction between generalized and partial seizures can be difficult to make and can evolve in the same patient over time. Reinus et al [43] demonstrated that 100% of patients with seizures and positive CT results had either an abnormal neurologic examination, an abnormal EEG, or a known malignancy. Although Hart et al [34] reported that 83% of patients younger than 16 years of age at the time of initial seizure experienced seizure recurrence, seizures that were associated with a neurologic deficit recurred in 100% of patients.
In children, seizures represent an extremely heterogeneous group of medical conditions ranging from benign cases, such as a simple febrile seizure, to life-threatening situations, such as status epilepticus. Underlying causes of seizures also represent a wide range of pathologies from idiopathic cases, usually genetic, to a variety of acute and chronic intracranial or systemic abnormalities. This document discusses appropriate utilization of neuroimaging tests in a child with seizures. The clinical scenarios in this document take into consideration different circumstances at the time of a child’s presentation including the patient’s age, precipitating event (if any), and clinical and electroencephalogram findings and include neonatal seizures, simple and complex febrile seizures, post-traumatic seizures, focal seizures, primary generalized seizures in a neurologically normal child, and generalized seizures in neurologically abnormal child. This practical approach aims to guide clinicians in clinical decision-making and to help identify efficient and appropriate imaging workup.
The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
Derivation of a clinical decision instrument to identify patients with status epilepticus who require emergent brain CT
2020, American Journal of Emergency Medicine
Citation Excerpt :
High risk criteria for acute intracranial findings were derived from both author consensus and prior literature (Fig. 1). Several studies have shown that malignancy is a risk factor for metastatic intracranial lesions leading to a seizure disorder [10,11]. Immunosuppression (AIDS, chronic steroids) could lead to intracranial abscess or infection while head trauma could lead to intracranial hemorrhage.
Studies have shown the value of CT brain imaging in adults with first-time seizures, but there are no recommendations regarding emergent brain CTs in persons with an established seizure disorders. Our study aimed to derive a clinical decision instrument (CDI) to determine which patients with status epilepticus (SE) require emergent brain imaging.
This was a retrospective chart review of patients who presented to our emergency department with SE between 2010 and 2018. Patients with first-time seizures were excluded. A priori, we defined high risk criteria for emergent imaging as well as positive findings on brain CT. High risk criteria included known malignancy, trauma, and immunosuppression. Positive CT scans included findings such as intracranial hemorrhage (ICH) and mass.
We identified 214 patients who met inclusion criteria Of the 181 patients without high risk criteria, 3% had positive CT scans. Of the 33 patients with high risk criteria, 10% had positive CT scans. The sensitivity, specificity, PPV, and NPV for our initial CDI were 38%, 85%, 9%, and 97%. Adding the criterion of prior ICH would have lowered our miss rate to 0.6%. Modifying our CDI to 1) History of ICH, 2) Malignancy, 3) Immunosuppression, and 4) Trauma would result in a CDI with sensitivity, specificity, PPV, and NPV of 87.5%, 87.4%, 21.2%, and 99.5%.
By using four criteria to identify high risk patients, we can defer CT scanning in the vast majority of patients with SE and known seizure disorders. This CDI should be prospectively validated before adoption.
The Emergency Department Evaluation of the Adult Patient Who Presents with a First-Time Seizure
2011, Emergency Medicine Clinics of North America
Citation Excerpt :
The necessity and timing of neuroimaging for patients with new-onset seizure remain controversial for emergency physicians. Noncontrast head CT scans reveal abnormalities ranging from 3% to 40% in patients with first-time seizure, which includes two-thirds with focal lesions and one-third with diffuse cerebral atrophy.7,8,16 The incidence of finding an abnormality is increased if the patient has a focal neurologic finding, focal onset of the seizure, history of malignancy, or HIV.17
Evidence-based medicine: Neuroimaging of seizures
2003, Neuroimaging Clinics of North America
ED utilization of computed tomography in a poisoned population
2002, American Journal of Emergency Medicine
The objective of this prospective, analytic study was to identify predictors and describe the demographic and clinical correlates of head computed tomography (CT) evaluation in patients with poisoning or drug overdose and altered mental status. Forty-three patients that were evaluated by head CT and 109 that were not evaluated by head CT were entered into the study at a poison control center. None of the 43 scanned patients had any acute findings on head CT. A logistic regression model yielded 4 predictors that were statistically associated with the ordering of a head CT scan: Glasgow Coma Scale (GCS) ≤8 (odds ratio [OR]: 2.3; 95% confidence interval [CI] 1.03-5.7); age ≥41 years (OR 5.3; 95% CI 2.2-13); use of drugs or abuse by history (OR 2.8; 95% CI 1.04-7.6); and witnessed seizure activity (OR 4.8; 95% CI 1.3-17.9). We also tested 2 additional models to identify predictors of hospital admission, 1 with and 1 without CT scan included as a covariate. In the first model, only GCS ≤8 was a significant predictor of admission (OR 10.7; 95% CI 2.4-47.2). When the use of head CT was added to the second model, it also emerged as an independent explanatory predictor of admission (OR 4.8; CI 95% 1.2-20.4) in addition to GCS (OR 10.1; 95% CI 2.2-45.4). In this pilot study, patients presenting to the emergency department (ED) with suspected poisoning or drug overdose were found to have a low likelihood of abnormal findings on head CT scan. Those among whom CT scans were obtained were more likely to be admitted to the hospital from the ED, despite negative findings. (Am J Emerg Med 2002;20:212-217. Copyright 2002, Elsevier Science (USA). All rights reserved.)

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Original contributionSeizure patient selection for emergency computed tomography

Study purpose:

Methods:

Results:

Conclusion:

Ann Emerg Med

Ann Emerg Med

Lancet

Lancet

Comput Radiol

Value of contrast enhanced CT scanning in the non-trauma emergency room patient

Neuroradiology

Emergency CT of the head: Indications and utilization

Md Med J

The diagnostic assessment of single seizures. Is cranial computed tomography necessary?

Arch Neurol

Value of computed tomographic scan in the evaluation of adult patients after their first seizure

Ann Neurol

Original contribution
Seizure patient selection for emergency computed tomography