Dramatic improvement of drug-resistant epilepsy following cerebral infarction: a case report

Abstract

Background

An estimated 30% of patients with epilepsy experience drug-resistant epilepsy, which is the failure to control seizures despite the use of two or more antiseizure medications. Although other treatment options are considered, these alternatives often prove ineffective.

Case presentation

A 60-year-old East Asian male patient diagnosed with drug-resistant epilepsy experienced several seizures daily despite being on eight different antiseizure medications. Seizures began at age 15. He underwent epilepsy surgery at age 34, yet the seizures persisted. An electroencephalogram revealed multifocal sharp waves in the left hemisphere. Cerebral hemorrhages at ages 47, 50, and 56 were caused by head trauma during seizures. The patient became wheelchair-bound and now resides in a nursing home. At age 58, after suffering an acute cerebral infarction due to occlusion of the left internal carotid artery, his daily seizures ceased entirely. Despite remaining wheelchair-bound, he did not experience a significant decline in his quality of life. The cessation of seizures has reduced his risk of further trauma, and he has remained seizure-free for 3 years on just one antiseizure medication.

Conclusion

Surgical treatments for epilepsy often fail, with insufficient resection being a leading cause of these failures. In some cases, extensive destruction from an ischemic stroke may be beneficial. Furthermore, this case suggests that infarction therapy could be a potential treatment for patients with drug-resistant epilepsy.

Background

Drug-resistant epilepsy is defined as the failure to control seizures despite the use of two or more appropriate antiseizure medications. An estimated 30% of all patients with epilepsy have drug-resistant epilepsy. Epilepsy can develop secondary to various mechanisms after a stroke, and one study found that 6.4% of stroke patients developed epilepsy [1]. We report a case of a patient with drug-resistant epilepsy who achieved seizure freedom after a cerebral infarction.

Case presentation

A 60-year-old East Asian male patient is being followed up in our neurology outpatient department for drug-resistant epilepsy. He has a history of status epilepticus following a fall while riding a bicycle at age 15, after which he started antiseizure medication. Due to poor seizure control, he underwent epilepsy surgery at another hospital when he was 34 years old, though the specific type of surgery performed remains unclear. The patient exhibited two types of seizure semiology: focal myoclonic seizures in his right arm and focal to bilateral tonic–clonic seizures. Despite surgery, his seizures remained uncontrolled and occurred several times a day, even with antiseizure medication polytherapy, including levetiracetam (1000 mg twice daily), valproate (500 mg twice daily), oxcarbazepine (450 mg twice daily), zonisamide (200 mg twice daily), topiramate (100 mg twice daily), lacosamide (50 mg twice daily), clobazam (5 mg twice daily), and clonazepam (0.5 mg once daily). Routine electroencephalography revealed frequent multifocal sharp waves in the left hemisphere, along with consistently observed theta slow waves throughout the left hemisphere (Fig. 1). At ages 47, 50, and 56, he suffered acute cerebral hemorrhages due to seizure-related trauma, which led to him becoming wheelchair-bound and reside in a nursing home. After the third cerebral hemorrhage, he began tapering off his antiseizure medications due to a very poor response. Interestingly, no increase in seizure frequency was observed during the tapering process. He was subsequently maintained on three medications: levetiracetam (1500 mg twice daily), topiramate (100 mg twice daily), and lacosamide (100 mg twice daily). At age 58, he experienced an acute cerebral infarction due to occlusion of the left internal carotid artery. Encephalomalacic changes in the left parieto-occipital area expanded to encompass the entire left cerebral hemisphere after the ischemic cerebral infarction (Fig. 2). After the ischemic stroke, his daily recurrent seizures completely ceased, and he was able to maintain a wheelchair-bound lifestyle. Before the stroke, frequent seizures had caused difficulty with speaking, which made it challenging to assess how much his speech impairment after the stroke affected his daily life. However, seizure freedom has reduced his risk of repeated trauma and improved his overall quality of life. He has remained seizure-free for more than 3 years while taking only one medication: lacosamide (100 mg twice daily).

Fig. 1.

Longitudinal bipolar electroencephalogram showing frequent multifocal sharp waves and consistent theta slow waves in the left hemisphere (asterisk indicates maximum negativity at electrodes F3, C3, P3, or T7, with independent occurrence)

Fig. 2.

Encephalomalacic changes observed in brain imaging. A Brain computed tomography image before cerebral infarction showing changes primarily in the left parieto-occipital area. B Brain magnetic resonance imaging image after cerebral infarction showing changes throughout the entire left cerebral hemisphere

Discussion and conclusions

This case describes a patient with drug-resistant epilepsy whose seizures persisted despite polytherapy and surgical intervention, but who achieved complete seizure freedom following an incidental cerebral infarction. Several reports have documented spontaneous improvement in tremor among patients with Parkinson’s disease following a stroke. These reports suggest that damage to anatomical areas associated with the symptoms may contribute to this improvement [2–4]. However, to our knowledge, there are no reports of intractable seizures disappearing following a cerebral infarction.

The patient’s brain lesion likely originated from a fall while riding a bike at age 15. Over time, the epileptogenic circuitry may have developed into a robust and complex network, involving a wide range of brain areas. Previously, it was believed that epileptogenesis was complete after the latent period—the interval between brain injury and the onset of the first clinical seizure—and that the probability of seizures would remain constant thereafter. However, observations suggest that the frequency and severity of seizures may gradually increase over time after a brain injury. This suggests that the process of epileptogenesis may continue beyond the latent period [5, 6]. Given that the surgery was performed 20 years after the initial brain insult, it is possible that not all of the patient’s epileptogenic lesions were removed. This could be due to the unclear delineation of epileptogenic lesions and the technical limitations of surgical techniques available in the mid-1990s.

After a stroke, secondary epilepsy can develop due to factors such as neural inflammation, glial scar formation, and alterations in neural connectivity [7]. The sudden cessation of habitual seizures following the cerebral infarction is likely due to the extensive destruction of the epileptogenic zone, including residual epileptogenic lesions. The maintenance of seizure-free status for more than 3 years after the infarction may be attributed to the concurrent destruction of normal brain tissue surrounding the epileptogenic lesion, which could have prevented the development of new seizure foci. Unlike surgery, where brain tissue is resected along macroscopic boundaries, cerebral infarction affects areas along the vasculature that are difficult to physically delineate. Paradoxically, this suggests that the lesions were effectively “removed” by the infarction process. Infarction therapy, which aims to remove tumors by occluding their blood supply and cutting off nutrients and oxygen, has shown promise in certain cancer treatments [8–10]. The complete resolution of our patient’s daily recurrent seizures following an accidental cerebral infarction prompts us to envision potential paradigm shifts in the treatment of drug-resistant epilepsy. This case raises the possibility that carefully planned induced cerebral infarction could serve as an alternative treatment option for drug-resistant epilepsy. However, since cerebral infarction can be a risk factor for developing epilepsy, it is crucial to carefully select appropriate patients.

Author contributions

JMK contributed to the conception and WL wrote the manuscript. DK and EYK revised the manuscript for intellectual content. All authors agreed on the final manuscript.

Funding

None.

Availability of data and materials

Not applicable.

Declarations

Ethics approval and consent to participate

This case report was approved by the Institutional Review Board (IRB) of Chungnam National University Hospital (IRB no. 2024–03-005). The requirement for informed consent was waived by the IRB, and all patient information was thoroughly anonymized.

Consent for publication

Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.

Competing interests

The authors declare that there are no competing interests.