Gamma Knife Radiosurgery in Obsessive Compulsive Disorder (OCD)

A chronic and frequently severe mental illness, obsessive-compulsive disorder (OCD) affects millions of people globally. Repetitive behaviours (compulsions) and intrusive thoughts (obsessions) are symptoms of OCD, which may severely limit a person’s capacity to go about their everyday life. Although psychiatric and psychological therapies are the main methods of managing OCD, new developments in neurosurgery, especially Gamma Knife Radiosurgery, give hope to those who are unable to respond to treatment.

This article examines OCD’s characteristics, causes, symptoms, available treatments, and the function of Gamma Knife Radiosurgery in current neuropsychiatric care.

Knowing OCD and the Brain

Neuroimaging research has repeatedly demonstrated that OCD is associated with disruption in the cortico-striato-thalamo-cortical (CSTC) circuit, namely in the orbitofrontal and anterior cingulate cortex. These regions play a role in behaviour control, emotional regulation, and decision-making—all of which are affected in OCD.

By making precise lesions or altering activity in specific areas, surgical or radiosurgical intervention aims to control these malfunctioning neuronal circuits in cases that are not responding to treatment.

Obsessive-Compulsive Disorder (OCD): What is it?

OCD is a neuropsychiatric condition characterised by recurrent obsessions and compulsive behaviours.

Unwanted, intrusive thoughts, desires, or visions that significantly increase worry or distress are referred to as obsessions. Common obsessions include obsessive sexual ideas, a demand for symmetry or exactness, fear of contamination, and fear of hurting oneself or others.

Repetitive actions or thoughts carried out in reaction to obsessions are known as compulsions. Over-washing hands, checking, counting, praying, and putting things in a certain manner are a few examples.

The frequency

About 1% to 2% of people worldwide suffer from OCD, which usually first manifests in late adolescence or early adulthood. Men and women are equally affected.

Reasons and Risks

Although the precise cause and effect of OCD is unknown, it is thought to be caused by an association of:

• Genetic Factors: The risk is increased if OCD runs in the family.
• Neurobiological Factors: The orbitofrontal cortex, anterior cingulate cortex, and basal ganglia in particular the caudate nucleus are among the brain circuits that are abnormal.
• Neurochemical Imbalances: One of the main causes is serotonin system dysfunction.
• Environmental Triggers: Stress, infections, or trauma can all serve as triggers. Examples of these include Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS).

Diagnosis

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria are used in clinical evaluations to identify OCD. The intensity of symptoms is evaluated using instruments like the Yale-Brown Obsessive Compulsive Scale (Y-BOCS).

Methods of Treatment

1. CBT, or cognitive behavioural therapy

• In particular, the most effective psychological treatment is Exposure and Response Prevention (ERP).
• Aids people in facing their anxieties and avoiding compulsive behaviours.

2. Drugs

• Sertraline, fluvoxamine, and fluoxetine are examples of selective serotonin reuptake inhibitors (SSRIs) that are frequently administered.
• Compared to depression treatment, higher dosages and longer duration of treatment could be required.

3. DBS, or deep brain stimulation

• DBS might be taken into consideration for severe, treatment-resistant patients.
• To modify malfunctioning circuits, electrodes are implanted in particular parts of the brain, such as the anterior limb of the internal capsule or the subthalamic nucleus.

4. GKR, or Gamma Knife Radiosurgery

Gamma Knife Radiosurgery: What is it?

Gamma Knife Radiosurgery is a non-invasive neurosurgery procedure that targets particular brain regions without making any incisions by using intensely concentrated radiation beams. It doesn’t actually include a knife, despite its name.

 The Process of Gamma Knife Radiosurgery for OCD

One of two brain areas is usually the focus of GKRS for OCD:

• The internal capsule’s anterior limb (ALIC)
• Cingulotomy of the cingulate gyrus

The most common radiosurgical procedure for OCD is stereotactic capsulotomy, which involves passing radiation to the ALIC. It is believed that pathological circuits that generate obsessive-compulsive symptoms are disrupted when this area, which connects the thalamus and frontal cortex, is damaged.

Key Steps:

1. Preoperative Assessment: A multidisciplinary team consisting of a neurosurgeon, neurologist, and psychiatrist evaluates the patient to rule out other diagnoses and confirm treatment-resistant OCD.
2. Imaging and Planning: MRI and CT images are used to precisely map the brain and plan the radiation dose and trajectory.
3. Radiosurgery Session: The procedure is often completed in a single session and causes no pain. Since they are conscious, patients can return home that same day.
4. Follow-up: Symptoms often don’t completely go away for three to twelve months.

Gamma Knife Benefits for OCD

• Non-invasive: No hospitalisation or incisions
• Very little chance of bleeding or infection
• Extremely focused: Little harm to the brain’s surrounding tissue
• General anaesthesia is not required.
• Quick recovery from an outpatient procedure

Results and Effectiveness

Research has demonstrated that GKRS can significantly reduce OCD symptoms in patients who are not responding to conventional treatments. Although response rates vary, studies indicate that up to 60–70% of properly chosen patients have clinically significant decreases in the severity of their symptoms as assessed by the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS).

Studies conducted over an extended period of time have likewise shown consistent advantages with few side effects. When adverse effects do happen, they are usually minor and can include headaches, temporary exhaustion, and in rare instances, emotional or cognitive abnormalities.

In conclusion

For those with severe, treatment-resistant OCD, Gamma Knife Radiosurgery is an advanced, evidence-based option. With the promise of better quality of life and functional recovery, it provides a lifeline to those for whom traditional treatments have failed, even if it is not a first-line therapy.

We encourage you to speak with our team of skilled neurosurgical and psychiatric professionals if you or a loved one is experiencing OCD and are thinking about advanced treatment options. They can decide together if Gamma Knife Radiosurgery is the best course of action.

Sources:

1. https://www.nimh.nih.gov/health/topics/obsessive-compulsive-disorder-ocd
2. https://iocdf.org/about-ocd/
3. https://iocdf.org/about-ocd/treatment/gamma-knife/#:~:text=What%20is%20Gamma%20Knife%3F,no%20danger%20to%20brain%20tissue.
4. https://pmc.ncbi.nlm.nih.gov/articles/PMC8803525/
5. https://pubmed.ncbi.nlm.nih.gov/35110917/
6. https://pmc.ncbi.nlm.nih.gov/articles/PMC8803525/