Sharma, Rishi

ABSTRACT We present the case of a 28‐year‐old right‐handed woman with medically refractory focal epilepsy. Her seizure semiology and electroencephalography (EEG) indicated a seizure onset zone in the right central‐parietal area. However, both MRI and PET scans were unremarkable, showing no focal lesions or areas of altered metabolism. Intracranial monitoring, with extensive evaluation of both hemispheres, confirmed the seizure onset zone in the right central‐parietal region. This area not only served as the site of seizure onset but also encompassed the primary sensory cortex.

Purpose: We present a unique technique applying F-wave latencies to assist in the diagnosis of peripheral neuropathy within the pediatric age group. Methods: We calculated an F-wave estimated deviance adjusted for limb length measurements, distal motor conduction velocity, and distal motor latencies. We compared the F-wave estimated deviance from the normal subjects with those with peripheral neuropathy (both axonal and demyelinating) to establish diagnostic accuracy in pediatric patients. Results: The normal range for the F-wave estimated deviance in the upper limb was −1 to +6 ms and in the lower limb was −8 to +5 ms. When compared with 82 subjects with peripheral neuropathy, there was a significant difference between the normal subjects and those with neuropathy (P values between 0.002 and 0.0005 for each of the individual nerves tested). Conclusions: The F-wave estimated deviance is independent of age and can be accurately applied to the electrodiagnostic testing of pediatric patients with suspected neuropathy.

ABSTRACT Introduction Existing normal value references for pediatric nerve conduction studies (NCS) are based on limited sample sizes with uncertain reliability, suggesting a need for better normative data. Methods Electronic medical records were reviewed for pediatric patients (0 to <18 years) with normal findings on electromyography and NCS during the period from January 1, 1997 through September 20, 2017. Electrodiagnostic and demographic data were collected. Gaussian and descriptive statistics were used to establish normal values by age group. Results In this study we analyzed 1,918 normal NCS on 1,849 unique pediatric patients. Patients were stratified by age: 0 to <1 month; 1 to <6 months; 6 to <12 months; 12 to <24 months; 2 to <3 years; 3 to <4 years; 4 to <5 years; 5 to <10 years; 10 to <15 years; and 15 to <18 years. Normal reference ranges for amplitude, conduction velocity, and distal latency were established for each age group for 4 motor and 4 sensory nerves. Discussion The large sample size of this study provides reliable reference values for interpreting pediatric NCS. Muscle Nerve 60 : 155–160, 2019