Posts Tagged epilepsy surgery
- Approximately 20% of all epilepsy is caused by acute acquired injury such as traumatic brain injury, stroke and CNS infection, with potential to prevent epilepsy
- No treatment to prevent acquired epilepsy exists; and very few clinical studies have been done during the last 15 years to develop such treatment
- We review possible reasons for this, possible ways to rectify the situations and note some of the ways currently under way to do so
- We further review “cures” of epilepsy that occur spontaneously, and after surgical and sometimes medical antiseizure treatments. We note the limited understanding of the mechanisms of such remissions and thus, at present inability to replicate them with targeted therapy
Vagus nerve stimulation (VNS) was the first neuromodulation device approved for treatment of epilepsy. In more than 20 years of study, VNS has consistently demonstrated efficacy in treating epilepsy. After 2 years, approximately 50% of patients experience at least 50% reduced seizure frequency. Adverse events with VNS treatment are rare and include surgical adverse events (including infection, vocal cord paresis, and so forth) and stimulation side effects (hoarseness, voice change, and cough). Future developments in VNS, including closed-loop and noninvasive stimulation, may reduce side effects or increase efficacy of VNS.
Epilepsy Treatment in Israel
Epilepsy is a spectrum of brain disorders which cause the development of abnormal activity of convulsions. Herzliya Medical Center Private Hospital conducts progressive minimally invasive techniques for the treatment of epilepsy.
What Is Epilepsy
Epilepsy is a disease of the central nervous system, characterized by a violation of the physiological activity of the brain cells. The main manifestation of epilepsy are seizures; the severity, frequency and nature of the disease can vary significantly.
Focal seizures are caused by abnormal activity at one part of the brain. The seizures appear in the form of sensory disorders, a brief loss of consciousness or involuntary contractions of the muscles of the upper or lower limbs. The seizures develop in response to pathological activity of the brain and may be accompanied by falling, twitching muscles and involuntary urination. Brain surgery for epilepsy is done to people to reduce or to stop the number of seizures they have. Surgery for epilepsy involves removing the part of the brain which causes the seizures or separating the part of the brain which causes seizures from the rest of the brain.
A single convulsive seizure is not regarded as a sign of epilepsy. An indication for an in-depth diagnosis is a history of two or more seizures not caused by any objective reasons.
- Neurological examination
- Electroencephalography (EEG). EEG is a graphical recording of the electrical activity of different brain regions. EEG can be performed in the waking state, during sleep, alone or under the influence of a trigger – factor, artificially stimulating seizure activity.
- Computed tomography of the brain (CT). Before planning brain surgery in Israel, neurosurgeons recommend carrying out a CT test; it lets the neurosurgeon visualize the structure of the brain, as well as to diagnose tumors, hemorrhage, cystic formation, against which the patient may develop seizures.
- Magnetic resonance imaging (MRI), both standard and functional. Epilepsy surgery usually requires a functional MRI to determine the areas of the brain that regulate the processes of speech, motor skills and other critical functions.
- Positron emission tomography (PET)
- Single photon emission computed tomography (SPECT). Experts in the field of neurosurgery in Israel recommend having a SPECT scan as well.
Epilepsy Surgery and Treatment in Israel
Treatment of epilepsy usually begins with medication. For most patients, the chronic long-term administration of antiepileptic drugs (AEDs) can reliably control the disease and prevent attacks or significantly reduce their frequency. With the ineffectiveness of drug therapy, a possible epilepsy surgery is considered. The indications for surgery are seizures that occur despite medication. Brain surgery in Israel for the treatment of epilepsy is carried out in cases when the source is located outside the areas of the brain responsible for vital functions: speech, motor skills, vision or hearing.
Surgery may be performed to isolate a certain part of the brain. Neurosurgery in Israel widely uses intraoperative MRI capabilities; during surgery, MRI is used for monitoring to ensure that the impact is applied on the selected area of the brain.
Herzliya Medical Center practices innovative methods of surgical treatment for epilepsy, which is a kind of stereotactic surgery. For the destruction of the convulsive center in the brain a laser beam is used, which causes the heating of tissues and their destruction. The laser beam serves as a thin catheter and is conducted into the cavity of the skull. Minimally invasive laser techniques do not require prolonged hospitalization, the patient can return to normal life within a couple of days.
[WEB SITE] Brain Connectivity Study Could Lead to Better Outcomes for Epilepsy Patients – Health News
The areas in purple are the regions of the brain where connectivity is significantly lower in patients with epilepsy, as compared to well patients.
The different images show the brain data from different angles. Image courtesy of Dario Englot
A new study found that patients with epilepsy have significantly weaker connections throughout their brain, particularly in regions important for attention and cognition, compared to individuals without epilepsy.
These weaker brain connections may reflect harmful long-term effects of recurrent seizures, but importantly the connectivity patterns may be used in the future to help locate which part of the brain is causing seizures, and may help doctors plan more effective surgeries.
In the study, 61 epilepsy patients and 31 controls subjects were analyzed using a non-invasive whole-brain imaging technique that detects magnetic fields produced by the electrical signals in the brain. The technique is called magnetoencephalography, and these MEG signals are used to examine the strength of connections in the brain.
Neurosurgery reisident Dario Englot, MD, PhD, sought to learn what the patterns of brain connectivity in epilepsy patients may tell us about the long-term effects of seizures on the brain. The findings suggest these connectivity patterns could help predict which individuals might benefit most from epilepsy surgery.
Intervening Earlier to Protect the Brain
The researchers found that patients who have had epilepsy for a longer period of time or have more frequent seizures had the most abnormal brain connectivity, suggesting that seizures may have progressive negative effects on the brain over time. This might advocate for early aggressive treatment of epilepsy that is not controlled with medication, to prevent these damaging effects of seizures that accumulate over time.
All patients in the study had seizures that were not controlled despite several anti-epileptic medications, and all ultimately underwent brain surgery to remove the part of the brain causing the seizures. After surgery, about two-thirds of patients became seizure-free. The investigators then examined whether brain connectivity patterns could predict which patients stopped having seizures after surgery.
More Precise Surgeries
Interestingly, those patients who became seizure-free were more likely to have an area of increased connectivity in the part of the brain causing seizures. This was not often seen in individuals who continued to have seizures after surgery. This suggests that although the brain is less connected overall in epilepsy patients, the part of the brain causing seizures may actually have increased connectivity.
Knowing this, MEG studies of brain connectivity could help determine which part of the brain is causing seizures, and may help predict a patient’s chance of becoming seizure-free after epilepsy surgery.
The study, published in the journal Brain, is the product off a multidisciplinary effort at the University of California, San Francisco, including biomedical engineer Srikantan Nagarajan, PhD, neurologist Heidi Kirsch, MD, neurosurgeon Edward Chang, M.D., and several other investigators.
University of California