Where, as above, C is annuity payment, PV is principal, n is number of payments, starting at end of first period, and i is interest rate per period. Equivalently C is the periodic loan repayment for a loan of PV extending over n periods at interest rate, i.
Refractory epilepsy is a seizure disorder that resists drug treatment. There is some debate among clinicians and researchers about how to define refractory epilepsy. As a result, this term is used in a variety of ways, and when a patient's epilepsy is described as refractory, resistant, or nonresponsive, it can be advisable to ask for more detail about what the diagnosis means.
Types of Epilepsy. There are several types of epilepsy, each with different causes, symptoms and treatments. Learn about idiopathic epilepsy, symptomatic epilepsy, and other types. Types of Seizures. Six types of seizures are most common. Learn the symptoms of myoclonic seizures. Refractory Epilepsy. If your doctor says you have refractory epilepsy, it means that medicine isn't bringing your seizures under control.