The LIMIT-NI clinical decision instrument reduces neuroimaging compared to unstructured clinician judgement in recurrent seizure patients

Abstract

ObjectiveThe LIMIT clinical decision instrument (CDI) was published in 2021 to safely reduce neuroimaging in patients with recurrent seizures. The LIMIT CDI had a sensitivity of 90%, negative predictive value of >99.9%, and reduced neuroimaging by 13.3%. However, the design of the original LIMIT CDI made it cumbersome to use. The goal of this study was to validate the streamlined LIMIT-NeuroImaging (LIMIT-NI) CDI and compare its performance to the original LIMIT CDI. MethodsThis was an observational study of patients presenting to three emergency departments with recurrent seizures. The LIMIT-NI CDI was applied to all patients. We calculated the test characteristics of the LIMIT-NI CDI and compared it to unstructured clinical judgement. Results3401 patients were screened, and 2125 patients were included in the final analysis. 16 patients (0.75%) had positive CTs; Both the LIMIT-NI CDI and clinician judgement identified all 16 patients with a sensitivity of 100.0% and a negative predictive value of 100.0%. Using unstructured clinical judgement, emergency providers ordered 835 brain CTs, while only 499 brain CTs would have been ordered using the CDI, a reduction of 15.8% (relative reduction 40.2%). ConclusionThe LIMIT-NI CDI demonstrated greater ease of application and improved test characteristics compared to the original LIMIT CDI. Compared to unstructured clinician judgement, the LIMIT-NI CDI reduced neuroimaging by 15.8% (relative reduction 40.2%) in recurrent seizure patients. The LIMIT-NI CDI can be used by physicians along with clinical judgement to reduce neuroimaging in the recurrent seizure patient.