At Cleveland Clinic's Epilepsy Center we strongly believe that the burden of epilepsy extends beyond a "seizure count”. Stopping your seizures and that the impact of the care we provide -- either medical or surgical -- should be long-lasting and should extend beyond simply "treating seizures."
During every outpatient clinic visit we measure seizure freedom or frequency (how often are seizures happening) in order to determine whether treatment is controlling, or reducing, the occurrence of seizures and the extent of such an improvement.
The large number of epilepsy surgeries performed at Cleveland Clinic and the long duration of follow-up available on our patients, allow us to accurately analyze our results and determine how well patients respond to surgery.
The Epilepsy Center used modern statistical methods of analysis to determine that in a group of patients evaluated, 78% were completely seizure-free two years following temporal lobectomy, 66% were seizure-free five years following surgery and more than 50% remained seizure-free more than a decade later.
Overall Seizure Treatment Outcomes
This chart shows the overall curve of seizure outcome showing similar long-term chances of seizure-freedom in adult and pediatric patients who underwent epilepsy surgery in our center: (plot represents data gathered from 1,418 patients operated on between 1996 and 2009). More than a decade following surgery, approximately half of the patients, of all ages, remain seizure-free.
|Time from Surgery ||1 Year ||2 Years ||5 Years ||10 Years ||12 Years |
|% Seizure-free (overall group) ||76% ||71% ||62% ||50% ||44% |
|% Seizure-free (adult epilepsy) ||72% ||66% ||56% ||48% ||43% |
|% Seizure-free (pediatric epilepsy) ||80% ||76% ||67% ||50% ||44% |
Below find treatment outcomes for specific surgeries
Temporal Lobe Surgery Treatment Outcomes
Temporal lobe resection is the most common type of epilepsy surgery. This curve illustrates the percent of patients who are seizure-free up to 15 years following a temporal lobe resection (N= 750 ). Our results are consistently more favorable than published averaged National data from the other epilepsy surgery centers.
|Time from Surgery ||1 Year ||2 Years ||5 Years ||10 Years ||15 Years |
|% Seizure-free (Cleveland Clinic) ||77% ||72% ||63% ||57% ||40% |
|% Seizure-free (national average) ||72% ||54% ||59% ||51% ||none available |
Frontal Lobe Surgery Treatment Outcomes
The following curve reflects seizure outcome on 304 patients with medically refractory frontal lobe epilepsy operated on between 1997 and 2009. Frontal lobe surgery is the second most common type of epilepsy surgery and has traditionally been considered a more challenging epilepsy population, where surgery is often more complicated.
|Time from Surgery ||1 Year ||2 Years ||5 Years ||10 Years |
|% Seizure-free ||77% ||72% ||63% ||57% |
Posterior Quadrant Resection Treatment Outcomes
The following curve reflects the seizure outcome of 96 posterior quadrant resections performed between 1997 and 2009. This is the least common type of epilepsy surgery. Our long-term results show very favorable seizure outcomes with up to 75% of the patients still seizure-free a decade after their resection.
|Time from Surgery ||1 Year ||2 Years ||5 Years ||8 Years |
|% Seizure-free ||81% ||79% ||75% ||75% |
Hemispherectomy Treatment Outcomes
Hemispherectomy is an aggressive epilepsy surgery treatment usually reserved for children with catastrophic epilepsies. At Cleveland Clinic Epilepsy Center, we perform the largest number of hemispherectomies in the country. As a result, a large amount of information is available relating to patients who have undergone this procedure. The following curve reflects the percent of patients who continue to be completely seizure-free up to 8 years following a hemispherectomy (N= 190).
|Time from Surgery ||1 Year ||2 Years ||5 Years ||8 Years |
|% Seizure-free ||88% ||83% ||75% ||69% |
We measure seizure severity (how strong are the seizures) in order to determine if our treatment is at least making seizures milder (less harmful) while we continue to work on eliminating them. This is done both in the small group of patients with drug-resistant seizures who need brain surgery to eliminate seizures (surgical group), and in the larger group treated mainly with anti-seizure medications (medical group).
Seizure severity is an important aspect of epilepsy. Cleveland Clinic Epilepsy Center uses the Liverpool Seizure Severity Scale (LSSS) b, a validated patient-completed questionnaire developed to quantify the patient’s own perception of change in seizures. Higher scores reflect more severe seizures. The graphs below indicate how seizure severity improved in both the medical and surgical adult patients treated in our Epilepsy Center.
Long-term chances of achieving and maintaining seizure freedom following different types of epilepsy surgery are shown in the graphs below. Whenever possible, our data was compared with national published data. We used the widely accepted Engel classification of seizure freedom to classify our seizure outcomes (seizure free = Engel class 1).
Seizure Severity in Medical Patients
Medical group: N=238 adult patients with >6 months of follow-up
Mean LSSS score was improved from 42.6 (± 25.1 s.d.) at initial visit to 25 (± 29.1 s.d.) at last visit (p<0.0001), with 46% of patients being completely seizure-free at last follow-up.
Seizure Severity in Surgery Patients
Surgical group. N=151 adult patients with >6 months of follow-up
The LSSS score improved from a mean of 31.3 (± 27.6 s.d.) before epilepsy surgery to 16.6 (± 25.9 s.d.) after surgery, with 65% of patients being completely seizure-free at the last follow-up.
For patients with epilepsy, quality of life is not only controlled by seizure frequency, but it is also determined by medication side effects, social functioning, employment, and many other important contributing factors. A successful epilepsy treatment should be translated into a “good” quality of life and not simply by “less seizures”. At Cleveland Clinic Epilepsy Center, we assess a patient's quality of life in every outpatient clinic visit using the Quality of Life in Epilepsy questionnaire (QOLIE-10). The questionnaire is a 10-item validated patient-completed questionnaire covering general to epilepsy-specific domains: epilepsy effects (memory, physical effects and mental effects of medication), mental health (energy, depression, overall quality of life) and role functioning (seizure worry, work, driving, social limits). Lower scores reflect a better quality of life.
QOLIE-10 scores improved in both the medical group and in the surgical group.
Quality of Life for Medical Patients
Medical group: N=362 adult patients with >6 months of follow-up
In the medical group, the improvement is reflected by a drop in the QOLIE-10 score from a mean of 23.6 (± 9.1 s.d.) at initial visit to a mean of 21.2 (± 8.8 s.d.) at last visit (p= 0.0003).
Quality of Life for Surgical Patients
Surgical group. N=154 adult patients with >6 months of follow-up
In the surgical group, the mean QOLIE-10 score improved from 25.4 (± 9.4 s.d.) to 21.5 (± 8.0 s.d.) (p- value=0.0001).
Mood disorders, especially depression, are very common in patients with epilepsy. We routinely screen for depressive symptoms in order to identify and address any depression as soon as possible. This is assessed using the Patient Health Questionnaire (PHQ-9)c. The questionnaire represents a patient-completed validated measure screening for depressive symptoms in the 2 weeks preceding the assessment. Mood improved in both the medical and surgical groups.
Mood Disorders in Medical Patients
Medical group: N=556 adult patients at last follow-up (follow-up range 1.1 to 14.3 months, mean = 5.4 months)
The mean PHQ-9 score at the initial outpatient visit was 8.3 (±6.8 s.d.) versus 6.9 (±6.7 s.d.) at the last follow-up visit, reflecting a 17% reduction in score severity (p=0.0006). The main improvement was observed in patients with moderate to severe depression at their initial visit.
Mood Disorders in Surgical Patients
Surgical group: N=68 adult patients at last follow-up (follow-up range 0.2-13.8 months, mean = 6.9 months)
The mean PHQ-9 score improved from 9.9 (±7.7 s.d.) to 6.7 (±7.2 s.d.) (p=0.02).
Multiple social limitations affect epilepsy patients as a result of their seizures. A major problem for adults with epilepsy is their inability to drive due to their uncontrolled seizures. Studies have shown after initiating treatment within our Epilepsy Center, more patients are able to resume driving. The graphs below indicate the change in the proportion of adult patients driving after a six-month, follow-up period.
Change in Driving Status in Medical Group
Medical group. N=454 adult patients with >6 months follow-up
There was a significant increase in the proportion of adult patients driving after a 6 month follow-up period from 40% at the initial visit to 46% at last follow-up (p=0.05).
Change in Driving Status in Surgical Group
Surgical group. N=112 adult patients with >6 months follow-up after surgery
There was a significant increase in the proportion of adult patients driving after epilepsy surgery, from 17 percent to 43 percent, based on at least six-months of follow-up.