Surgical and Neuromodulation Options

When medications do not control Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis (MTLE-HS), your care team may suggest procedures to stop or reduce your seizures. These options fall into two main categories: potentially seizure-free treatments, which aim to stop seizures entirely, and seizure-reducing treatments, which aim to reduce the frequency and intensity of seizures ^[1][2].

Potentially Seizure-Free Options: Removing the Source

If your seizures start in one specific, clearly identified spot (unilateral), doctors may recommend removing or destroying that tissue. Both procedures carry risks such as bleeding, infection, and changes to memory or language ^[3].

Anterior Temporal Lobectomy (ATL)

This is the “gold standard” surgery for MTLE-HS and has been performed for decades ^[1]. A surgeon removes a portion of the temporal lobe, including the scarred hippocampus ^[4].

• Success Rate: This offers a high chance of becoming completely seizure-free. Studies show that roughly 60% to 80% of carefully selected patients achieve seizure freedom after ATL ^[1][3].
• The Trade-off: It is an invasive open-brain surgery and requires a longer recovery time. Because it involves removing brain tissue, there is a risk of changes to your verbal memory (especially if the surgery is on your dominant side) and small changes to your peripheral vision ^[3][5].

Laser Interstitial Thermal Therapy (LITT)

This is a newer, minimally invasive alternative to ATL. A surgeon uses a laser probe, guided by a real-time MRI, to ablate the scarred hippocampus through a tiny hole in the skull ^[6].

• Success Rate: Seizure-freedom rates for LITT are often slightly lower than for ATL, typically ranging from 55% to 66% in selected groups ^[6][7].
• The Advantage: Recovery is much faster, often involving only a short hospital stay ^[1]. Because the laser is very precise, it may carry a lower risk for certain types of memory and language decline compared to traditional surgery for some patients ^[8]. However, it is still invasive brain surgery with risks of bleeding or incomplete ablation.

Seizure-Reducing Options: Calming the Network

If your seizures come from both sides of the brain, are poorly localized, or if surgery is too risky, your team may suggest neuromodulation. These devices do not remove tissue; instead, they use electrical pulses to “interrupt” seizure activity ^[2].

Responsive Neurostimulation (RNS)

The RNS System is like a “brain pacemaker.” A device is placed in the skull with wires leading to one or two identified seizure foci. It constantly monitors your brain waves and delivers a small electrical pulse when it detects abnormal activity ^[9].

• Results: Most patients see a significant reduction in seizures (median reduction of about 70% after several years), but it rarely stops all seizures permanently ^[9].
• Benefit: It provides your doctors with years of data on your brain activity, which can help fine-tune your treatment, though it requires programming and battery changes ^[10].

Vagus Nerve Stimulation (VNS)

A VNS device is implanted under the skin of the chest, with a wire wrapped around the vagus nerve in the neck. It sends regular pulses of electricity to the brain to help modulate the seizure network ^[11].

• Results: Similar to RNS, it is designed to reduce seizures over time. About 50% of patients see their seizure frequency cut in half after a year or two of treatment ^[12][11].
• Side Effects: You may notice temporary hoarseness, a “tickle” in the throat, or shortness of breath while the device is actively stimulating the nerve ^[12].

Making the Choice

Choosing between these options requires careful presurgical evaluation to determine your candidacy based on your brain network, not just your preference for a shorter recovery. Your multidisciplinary team will help you weigh the risks and benefits of each option.