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Background

Background

This calculation tool combines two distinct yet complementary approaches derived from the MRC Multicentre Trial for Early Epilepsy and Single Seizures (MESS) to assess the likelihood of seizure recurrence and inform decision-making in clinical and practical scenarios, including driving eligibility and treatment planning.

Part 1: Risk of Recurrence After a First Seizure and Implications for Driving

The Risk of Recurrence After a First Seizure and Implications for Driving tool calculates the likelihood of seizure recurrence after an individual’s first unprovoked seizure.

Variables Used:

  1. Aetiology:
    • Cryptogenic/Idiopathic: No identifiable cause or underlying condition.
    • Symptomatic: Seizure linked to a past condition (e.g., head injury, infection, stroke, or other neurological issues).
  2. Epilepsy in First-Degree Relative:
    • Yes: A history of epilepsy in immediate family members (parents or siblings).
    • No: No family history of epilepsy.
  3. Seizures Only While Asleep:
    • Yes: All seizures occurred exclusively during sleep.
    • No: Seizures occurred during wakefulness or a combination of sleep and wakefulness.
  4. EEG Results:
    • Normal: No epileptiform activity detected.
    • Abnormal: Presence of epileptiform activity (e.g., focal or generalized spikes, spike-and-wave patterns).
    • Not Done: EEG test was not conducted.
  5. CT/MRI Scan Results:
    • Normal: No structural abnormalities detected.
    • Abnormal: Structural abnormalities found (e.g., lesions, scarring, or other brain abnormalities).
    • Not Done: Imaging was not conducted.

Outputs:

  1. Risk of Seizure Recurrence:
    • This calculated risk is based on the variables entered and indicates the probability of a seizure recurrence.
  2. Chance of Seizure in the Next Year (COSY):
    • This tool informs whether an individual may be fit to drive, based on their specific seizure recurrence risk. 

Part 2: MESS Prognostic Index Tool

The MESS Prognostic Index Tool is designed to estimate the likelihood of seizure recurrence and guide treatment decisions after a single seizure or early epilepsy diagnosis. Derived from the MRC Multicentre Trial for Early Epilepsy and Single Seizures (MESS), the tool categorizes patients into six distinct groups based on a combination of risk level (low, medium, high) and treatment timing (immediate or delayed).

Variables Used:

  1. Number of Seizures Before Diagnosis:
    • Single Seizure: Indicates a low baseline risk of recurrence.
    • Two to Three Seizures: Suggests a moderate increase in risk.
    • Four or More Seizures: Associated with a high risk of recurrence.
  2. EEG Results:
    • Normal EEG: Indicates no abnormal epileptiform activity, contributing to a lower risk profile.
    • Abnormal EEG: Includes epileptiform or slow-wave abnormalities, significantly increasing the risk.
  3. Presence of Neurological Disorders:
    • No Neurological Disorder: Suggests a lower risk category.
    • Neurological Disorders (e.g., impairments, learning disabilities): Associated with higher seizure recurrence risks.
  4. Impact of Treatment Timing:
    • Immediate Treatment: Reduces recurrence risk in medium and high-risk groups during the initial years.
    • Delayed Treatment: Allows natural progression, recommended for low-risk patients where benefits of treatment are minimal.

Risk Classifications:

Patients are categorized into three primary risk groups based on the cumulative score from these variables:

  • Low Risk (0 points): Single seizure, normal EEG, and no neurological disorders.
  • Medium Risk (1 point): Two to three seizures, or a single seizure with either an abnormal EEG or neurological disorder.
  • High Risk (2–4 points): Four or more seizures, or a combination of abnormal EEG and neurological disorders.

Outputs:

  1.  
  1. Risk of Seizure Recurrence:
    • This calculated risk is based on the variables entered and indicates the probability of a seizure recurrence.
  2. Chance of an Occurrence of a Seizure in the next Year (COSY):
    • This tool informs whether an individual may be fit to drive, based on their specific seizure recurrence risk.

Disclaimer

  • Most of the models featured on this website were not developed by us. For detailed information about each model or calculator, please refer to the links to the original publications. This website provides an overview of selected prognostic models for epilepsy for demonstration purposes only. If you believe a model should be removed, please contact us, and we will address your request promptly. We do not guarantee the accuracy, reliability, or scientific integrity of these calculators. The implementations may contain errors and could produce unreliable results. These prognostic tools are based on scientific research and are intended for demonstration purposes only. The clinical usefulness and robustness of most of these models have not been adequately tested, and they should not be used to guide medical decisions. All liability is excluded.
  • 2025, SeLECT consortium, [email protected]