Surgery that treats disorders of brain and nerve function, movement disorders,
epilepsy, severe psychiatric illness, and chronic pain, by precisely modulating or
interrupting the circuits responsible. A patient education overview for patients and
referring clinicians.
Overview
What functional neurosurgery is
Most neurosurgery treats a structural problem, a tumor, a bleed, a compressed nerve.
Functional neurosurgery is different: it treats disorders of how the nervous
system works. The anatomy may look normal, but a circuit is misfiring, producing
a tremor, a seizure, an obsession, or relentless pain. The goal is to correct that activity
while preserving everything else.
The work is stereotactic: targets deep in the brain are reached with
millimeter precision using image-guided planning, often through a small opening or, increasingly,
with no incision at all. Two strategies run through the whole field, modulating
a circuit with an adjustable, reversible implanted device, or interrupting it
with a small, precise lesion. The same toolbox, deep brain stimulation, focused ultrasound,
radiosurgery, and connectivity-guided targeting, is applied across four broad areas.
This site is a patient-education overview. Each area links to a dedicated, in-depth guide.
Areas of care
Four areas, one approach
Functional neurosurgery is organized around the kind of problem being treated. Each area below
has its own detailed guide, the conditions it covers, how candidates are evaluated, and
the specific procedures available.
Movement Disorders
When medication can no longer control tremor, stiffness, slowness, or involuntary movements, deep brain stimulation and focused ultrasound can restore function.
For drug-resistant focal epilepsy, surgery can remove, disconnect, ablate, or modulate the network that generates seizures, guided by modern intracranial mapping.
For severe, treatment-resistant illness, neuromodulation and precise lesioning can modulate the circuits whose dysregulation drives disabling symptoms.
Covers: treatment-resistant OCD · depression · PTSD (research stage, not yet widely applied in clinical practice)
For pain that no longer responds to other care, neuromodulation, targeted treatment of trigeminal neuralgia, and precise procedures can offer durable relief.
Movement disorders, epilepsy, severe psychiatric illness, and chronic pain look like entirely
different problems, but they share a logic. Each is, at its core, a disorder of a
circuit: a network of brain regions and the pathways between them, firing in a
pattern that produces symptoms. Functional neurosurgery intervenes at a precise node of that
circuit.
Increasingly, the target is chosen not from anatomy alone but from each patient's own
structural connectivity, tractography that maps the white-matter pathways
a given target engages, so an intervention reaches the intended network and spares the rest. This
connectivity-guided approach is a focus of the research program at the Neuronium Neuroscience
Institute, and it runs through all four areas of care.
Map the circuit
High-resolution imaging and tractography reconstruct the network involved and the precise target within it.
Modulate or interrupt
An adjustable, reversible device stimulates the circuit, or, where preferred, a precise lesion interrupts it.
Preserve function
Throughout, the aim is to relieve symptoms while protecting movement, language, memory, and personality.
Technology
A shared toolbox
The same core technologies appear across movement, epilepsy, psychiatric, and pain surgery
, applied to different targets for different conditions.
Deep Brain Stimulation (DBS)
Thin electrodes deliver adjustable, reversible stimulation to a precise deep target. The workhorse of movement-disorder and psychiatric surgery.
MR-Guided Focused Ultrasound
Hundreds of ultrasound beams converge to make a precise lesion deep in the brain, with no incision and no implant, under real-time MRI thermometry.
Stereotactic Radiosurgery
Focused radiation treats a target without opening the skull, used for tremor, trigeminal neuralgia, and selected lesions.
Radiofrequency Lesioning
A stereotactically placed probe makes a controlled, precise lesion, for tremor, pain pathways, and seizure foci.
Implanted Neuromodulation
Responsive and scheduled stimulation systems, from spinal cord and nerve stimulators to closed-loop brain devices.
Connectivity-Guided Targeting
Each patient's tractography refines the target so stimulation or lesioning engages the intended network and limits side effects.
About the author
Who wrote this site
AFA
Ahmet Fatih Atik, MD
Neurosurgeon · stereotactic and functional neurosurgery
Dr. Atik is a neurosurgeon whose practice focuses on stereotactic and functional
neurosurgery across its full range, deep brain stimulation and focused ultrasound
for movement disorders, surgery for drug-resistant epilepsy, neuromodulation and
lesioning for treatment-resistant psychiatric illness, and procedures for chronic pain.
Alongside clinical work, he conducts research on network-level analysis of brain
circuits and on integrating each patient's structural connectivity into surgical
targeting. This research program is housed at the Neuronium Neuroscience Institute,
an independent research entity.
This site is a patient-education resource written by Dr. Atik. It is maintained by him personally and does not, by itself, constitute medical advice.