Post-operative seizures do not mean that the seizures are completely terminated in epileptic patients, and there is still a high incidence of seizures in the post-operative period of about 3 months, mainly due to post-operative cerebral edema, surgical stimulation, electrophysiological disturbance of the brain, and unstable drug concentration;
After surgery, attention should be paid to.
1, reasonable and standardized medication; at least 2 years, under the guidance of a doctor.
2, pay attention to diet, etc., do not drink drinks containing coffee, strong tea, tobacco and alcohol should be abstained.
3, regular life, avoid overwork, avoid stimulation.
4, less watching TV, games, computers, etc., light stimulation is one of the important factors that induce epilepsy, long time watching TV, playing games, playing computers, etc. can induce epilepsy; quit these factors can significantly reduce seizures
Mechanisms of post-surgical seizure recurrence
Epilepsy surgery is the conventional treatment for intractable focal canker sores, and seizure recurrence after resection depends on the type and location of the underlying pathological changes. Although the prognosis is good (60%-90% seizure-free) in temporal lobe epilepsy-independent lesions, epilepsy surgery in other brain tissue regions rarely achieves such a high success rate. Those who fail surgery usually have a seizure reoccurrence 6-12 months after surgery. These post-surgical seizures can be classified into 3 types i.e. habitual, non-habitual and adjacent seizures, with different pathological mechanisms. Understanding these mechanisms will undoubtedly be an important guide for the selection of post-surgical treatment options.
1. Habitual seizures
The seizure symptoms after surgery are the same as those before surgery, and the same clinical seizures are produced because the tissues around the adjacent previously epileptogenic lesions are not completely removed and become new epileptogenic areas or mature lesions. The EEG at the time of seizure may still show the same epileptic origin as before surgery, but the waveform may be altered, possibly because of the postoperative skull defect and partial removal of tissue.
Habitual seizures can occur immediately after surgery, or months or years after surgery, usually within the first year of surgery; however, they rarely occur after a long period of seizure absence (which may last more than 5-10 years). Habitual seizures within the first year after surgery are more likely to become persistent or intractable, while habitual seizures occurring after the first year or even more than 10 years are easily controlled with medication and do not become drug-resistant epilepsy.
In 1983, Rasmussen proposed the phenomenon of “running down” to explain the gradual disappearance of habitual seizures, as the surgical removal of a major part of the epileptogenic region may facilitate the natural evolution of epilepsy. Later, Salanova et al. found that the epileptogenic region was smaller in those without seizures compared to those with “running down” after surgery. These studies suggest that there may be residual epileptogenic regions with a higher threshold of epileptic discharges that are ultimately insufficient to cause persistent clinical seizures, presumably due to maturation of inhibitory loops or disruption of excitatory connections.
2. Non-habitual seizures
In some patients, the seizure symptoms after surgery are different from the preoperative habitual seizures and change to a new clinical type, called non-habitual seizures.
The mechanisms that lead to non-habitual seizures are:
(1) Persistent epileptogenic foci and symptom-producing functional brain areas are removed, changing the symptoms of epileptic seizures. For example, right foot clonic seizures continue to occur in the right upper arm after removal of the primary motor cortex (M1) foot area.
(ii) The epileptogenic focus or epileptic seizure spreading pathway was selectively partially removed, thus altering the clinical presentation of the patient. Epileptic discharges can propagate through different loops, and this mechanism may also explain why post-surgical patients experience aura after discontinuation of medication without a tendency to develop epileptic seizures with motor symptoms or loss of consciousness.
The typical abdominal aura is particularly common after surgery in patients with temporal lobe epilepsy, and it is hypothesized that some of the epileptogenic foci that are not removed still constitute epileptic discharges that cause abdominal aura when they spread to the insula, but that such epileptic discharges do not cause automaticity and loss of consciousness. At the same time, secondary generalized seizures are relatively increased in temporal lobectomized individuals, probably because standard temporal lobectomy does not usually remove selective contact brain regions of the amygdala-hippocampus with the pons-midbrain, such as the insula and septum, and thus epileptic discharges preferentially pass through these structures after temporal lobectomy leading to a relatively higher proportion of secondary generalization.
(iii) Exposure or maturation of other epileptogenic foci after surgery may result in a new type of seizure. Defining the extent of the epileptogenic foci is a difficult problem because, for one, it is more extensive than the actual site of initiation of epileptic discharges; and, for another, maturation of the epileptogenic foci takes time to cause seizures, e.g., MCD, although congenital, can be resting for more than 10 years before the onset of epilepsy. Therefore, it can be assumed that the formation of new epileptogenic foci after surgery may reflect the maturation process of the epileptogenic focus. The surgical scar may also become a new epileptogenic focus and produce new clinical seizure symptoms.
3. Adjacent seizures
Used to indicate focal simple motor seizures immediately after temporal lobe surgery (1-2 weeks), often without loss of consciousness. 20-58% of patients experience such seizures, either due to surgical irritation, edema, bleeding or infection, or due to reduced AED blood levels, which have not been found to be a common factor in seizures in recent studies.
Adjacent seizures must be distinguished from acute postoperative seizures, which are all types of seizures in the first week after surgery, with an incidence of 20%-49% and are associated with a poor prognosis, but do not preclude later conversion to seizure-free, which can still occur in 33%-51% of patients. In general, adjacent seizures are less harmful. Malla et al. reported that 75% of seizures eventually disappeared in patients with focal motor seizure aura and generalized tonic-clonic seizures after surgery.
However, the same acute postoperative seizures as habitual seizures (46%-85%) have a poor prognosis. Most studies concluded that acute postoperative seizures occurring in the first 24 h of week 1 or late in week 1 did not differ significantly in final outcome; only one clinical observation reported that seizures with only 1 seizure or limited to day 1 after surgery were more likely to become seizure-free than multiple seizures or seizures late in week 1.
In conclusion, the majority of patients were seizure-free after surgery or had habitual seizures originating from around the resected cortex, the latter occurring up to 10 years after surgery, and occasionally a gradual decrease in the number of seizures was observed, showing a “tapering” phenomenon. However, most acute postoperative seizures, especially early habitual seizures, are associated with a poor prognosis.
Isolated aura symptoms or secondary generalized seizures are more common after surgery, and nonhabitual seizures may also be observed. Therefore, it is clearly important to collect comprehensive information about the relevance of surgical outcome before surgery, to carefully evaluate and study the risk factors and mechanisms of reoccurrence in each patient after surgery, and to continue and choose to give appropriate AED treatment, both in order to ensure surgical efficacy and to help patients overcome the disease and regain their self-confidence.