Functional Neurosurgery Center

Outpatient Clinic

Tuesday am, pm
Wednesday am


山本 一徹

Kazuaki YamamotoDirector of the Center



Areas of Interest

Stereotactic and Functional Neurosurgery

Education and Training

2010 MD, Sapporo Medical University
2010-2016 Residency, Shonan Kamakura General Hospital, Kamakura, Kanagawa, Japan
2019-2020 Fellowship, Stereotactic and Functional Neurosurgery, Tokyo Women’s Medical University, Shinjuku, Tokyo, Japan
2020-2022 Fellowship, Stereotactic and Functional Neurosurgery, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada

At 17 years of age, Dr. Yamamoto was impressed at the tremendous therapeutic effects of the surgery for a patient with Parkinson's disease. In the video that he watched, a man who couldn't even take a sip of water by himself because of his parkinsonian motor symptoms underwent stereotactic functional surgery in the United States. The radiofrequency ablation procedure successfully blocked the abnormal neural circuit of Parkinson's disease in the brain and improved the patient's motor symptoms. His quality of life dramatically improved after the procedure, and he could even play soccer with his grandson. The mystery of the brain attracted Dr. Yamamoto, and this shocking experience led him to stereotactic and functional neurosurgery.

After the training in general neurosurgery, Dr. Yamamoto learned stereotactic and functional neurosurgery under Prof. Takaomi Taira in Tokyo and Prof. Andres Lozano in Toronto, experiencing many cases.

Board Certificates

  • Japan Society for Stereotactic and Functional Neurosurgery Technical
  • Board Certification for Stereotactic and Functional Neurosurgery
  • Board Certified Neurosurgeon of Japan Neurosurgical Society
  • Board Certified Spinal Neurosurgeon of Neurospinal Society of Japan
  • Board Certified Spinal Neurosurgeon of Japanese Society for Spine Surgery and Related Research

Dr. Yamamoto performs stereotactic neurosurgery (DBS: deep brain stimulation, RF: radiofrequency ablation, and FUS: focused ultrasound) as well as spinal cord stimulation and intrathecal baclofen. He also sees patients in the perioperative care and outpatient clinic.

What is Functional Neurosurgery? – surgical treatment of tremors, stiffness, parkinsonian symptoms, etc.

Functional neurosurgery is a specialty field to surgically treat movement disorders, chronic pain, epilepsy, etc., caused by abnormalities in the nervous system. Movement disorders include various involuntary motor symptoms such as tremors of the limbs or the head, stiffness, twists, flexion, or extension of a part or the entire body, etc.

These symptoms often impair patients' daily life, lowering their quality of life. Our center aims to restore neurological function and improve patients' quality of life with functional neurosurgery.

Clinical Indications:

Parkinson's disease, essential tremor, other types of tremors such as poststroke tremor, dystonia (generalized, segmental, focal dystonia such as writer's cramp, musician's cramp, occupation-related dystonia, yips), spasticity, intractable pain, Huntington's disease (chorea), tic (Tourette's syndrome), other types of movement disorders, etc.

Parkinson's disease

Parkinson's disease manifests various symptoms such as tremor in the limbs at rest, rigidity, slowness, balance issues while walking, etc. Some patients have resting tremor as a predominant symptom, and others have various symptoms. Parkinson's disease is a progressive disorder, meaning its symptoms worsen over time.
In addition to parkinsonian symptoms, treatments at our center can potentially reduce patients' medication doses and improve medication-induced side effects such as dyskinesia.

The standard treatment for Parkinson's disease is medical therapy; however, surgical management at our center becomes an option if the disease has progressed and is disabling in patients' daily life.

Treatment options: deep brain stimulation, focused ultrasound, radiofrequency ablation, etc.

Essential tremor

Part of the body shakes without any evidence of disorders in brain images. Most patients have tremor (shakes) when moving their limbs in writing or drinking, but some patients have tremors in the feet or head. Tremors tend to become worse with age. A family history of essential tremor is common for patients with essential tremor.

Treatment for essential tremor usually starts with medications; however, approximately 50% of patients fail medical treatment due to a lack of therapeutic effects or medication-induced side effects.

Treatment options: focused ultrasound, radiofrequency ablation, etc.


Part or the entire body involuntarily becomes stiff or rigid, twists, flexes, or extends. There are various types of dystonia including musician's cramps (dystonia of the fingers, hands, feet, or mouth impairs playing musical instruments such as piano, guitar, drum, flute, trumpet, etc.), writer's cramp (the fingers or wrist flexes or extends while writing), yips (athletes such as golfers or baseball players experience involuntary flexion or extension of the shoulder, elbow, or wrist), barber's cramp (the fingers or wrist flexes or extends and movement of the hand gets stuck when using scissors), cervical dystonia (spastic torticollis: the head and neck involuntarily turns and extends), etc. There are hereditary and non-hereditary types of dystonia; thus, many patients with hereditary dystonia have a family history of dystonia.

In case dystonia does not respond to medications or Botox, surgery at our center becomes an option.

Treatment options: radiofrequency ablation, deep brain stimulation, etc.


The limbs extend and become stiff following cerebral palsy, spinal cord injury, head injury, or stroke. Spasticity often comes with pain, which, not only spasticity itself, affects patients' daily life.

Severe spasticity that does not respond well to medications or Botox is indicated for surgery.

Treatment options: intrathecal baclofen, selective dorsal rhizotomy, selective peripheral neurotomy, etc.

Intractable pain

Intractable pain is a pain refractory to treatments. There are various causes of the pain including phantom pain, complex regional pain syndrome (CRPS), pain secondary to diabetes mellitus, peripheral neuropathic pain such as radiculopathy and plexopathy, pain syndromes secondary to strokes such as cerebral infarction or hemorrhage (e.g., thalamic pain), failed back surgery syndrome (FBSS, back or leg pains sustaining even after spinal surgeries), etc.

Treatment options: radiofrequency ablation, deep brain stimulation, spinal cord stimulation, etc.

Surgical procedures

1.Stereotactic neurosurgery

In stereotactic neurosurgery, special devices are used to precisely target deep brain structures with millimeter- or micrometer-accuracy. Stereotactic neurosurgery includes the following procedures:

1-1. DBS: deep brain stimulation

Electrodes implanted in the brain electrically stimulate deep brain structures to improve patients' symptoms. The electrodes are connected to a stimulator (pulse generator) implanted under the skin through extension wires. During the procedure, therapeutic effects and the absence of side effects are confirmed by a trial stimulation before securing the electrodes.

Pros: Adjustability (stimulation parameters such as voltage, frequency, location, etc.) and reversibility (stimulation can be turned off at any time, and devices can be removed if desired).

Cons: This procedure needs implantation of electrodes, extension wires, and a pulse generator; skin incision; and burr holes in the skull with a diameter of approximately 1 cm (the holes are covered with caps).

1-2. RF: radiofrequency ablation

An electrode is inserted in the brain to make a small burn around the tip and shut the abnormal neural circuit and improve symptoms. During the procedure, therapeutic effects and the absence of side effects are confirmed by a trial stimulation before ablation.
Pros: This procedure does not need the implantation of foreign bodies such as electrodes or a pulse generator.
Cons: A skin incision (2.5-3 cm in length, behind the hairline in most cases) and a burr hole (approximately 1 cm in diameter, covered with a cap at the end of surgery) are necessary.

1-3. FUS: focused ultrasound (HIFU: high-intensity focused ultrasound)

Procedure without a skin incision. Approximately 1,000 ultrasound beams focus at a point in the brain to heat the target and improve symptoms. During the procedure, therapeutic effects and the absence of side effects are confirmed with a moderate temperature increase providing reversible effects.

The tremor stops during MRgFUS.

Pros: Incisionless procedure without burr holes.
Cons: Hair shaving on the day of the procedure. Difficulty in increasing the temperature in the target in some cases (this is predictable by a pre-procedural CT scan).

2. SCS: spinal cord stimulation

This is a treatment to electrically stimulate the spinal cord using electrodes inserted from the back into the epidural space. Indications for this treatment include intractable back or leg pain sustaining even after back surgery (FBSS: failed back surgery syndrome), complex regional pain syndrome (CRPS), pain secondary to diabetes mellitus, etc.

3. ITB: intrathecal baclofen

Baclofen is continuously delivered from an implanted pump into the intrathecal space. Baclofen is highly effective when administered intrathecally, directly acting on the spinal cord. The expected benefits of this treatment include 1) facilitation of patients' mobility, 2) facilitation of patients' care by their families, and 3) improvement of pain secondary to spasticity.

Characteristics of our center

Treatment by an experienced functional neurosurgeon

A functional neurosurgeon who has experienced many cases and treatments treats all patients.

Various treatment options

We offer multiple treatment modalities including deep brain stimulation, radiofrequency ablation, and focused ultrasound. After explaining these options and discussing them with the patients and families, we suggest the best option from an expert viewpoint.

Patients from distant places

We offer our treatments to patients from any country in the world. Even if the patient is from a distant place, we provide the best treatment option accordingly. Please feel free to contact us.

The diseases in the field of functional neurosurgery are often hard to diagnose, and there are many patients who are not correctly diagnosed or do not know they can be treated, thus preventing the patients from appropriate treatments even if they have suffered from symptoms for many years. We offer our treatments to all patients from an expert viewpoint. If you have any symptoms described above, please feel free to contact us.

To patients and their families:

We will consider treatments so we can maximize therapeutic benefits to improve patients' symptoms and quality of life. An experienced functional neurosurgeon treats all patients. We understand that people might feel anxious about brain surgery or failure. Please ask us any questions to relieve your anxiety. We offer treatments only after we explain the details of the procedures and the patients and families agree to our treatments. Please feel free to contact us if you have any symptoms described above.

NOTE: On this website, easy-to-understand words and expressions are used avoiding medical technical terms as much as possible.
Please ask any questions if there are contents hard to understand.

Clinic Appointments

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