What is Tolosa-Hunt Syndrome?

Tolosa-Hunt syndrome (THS) is a condition affecting the eyes. It causes severe headaches and pain around the eye. It usually happens due to swelling in areas behind the eye, this affects the nerves that control eye movement. As a result, these headaches are also linked to reduced eye movement.¹

What Causes Tolosa-Hunt Syndrome?

The exact cause of THS is not fully known but it is an autoimmune response where the immune system attacks healthy tissues causing inflammation.² Two areas are typically affected - these are the cavernous sinus and the superior orbital fissure. The immune system forms small deposits of immune cells (Referred to as granulomas). These granulomas are formed in response to something the immune system sees as danger. This can cause irritation and discomfort around the nerve, causing pain around the eyes and headaches. This type of inflammation is known as granulomatous inflammation. THS is an autoimmune response where the immune system attacks healthy tissues. 

Symptoms of Tolosa-Hunt Syndrome

There are several symptoms associated with THS, the majority causing pain around the eyes and face/head. These can come on suddenly or build up over time. Symptoms include:³

• Severe pain near the eye - sharp/intense pain around one eye, only one side of the face is affected. This pain can last a few days or weeks
• Difficulties with moving the eye - may be unable to move the affected eye in particular direction 
• Double vision - can see an object twice as the eye can move properly 
• Drooping eyelids - eyelids can droop and make your seem partially closed
• Changes to vision - this is a rare symptom where people may blurred vision or some blindness in the affected eye
• Numbness near the forehead, cheek or jaw
• Swelling around the eyes

Diagnostic Criteria

The International Classification of Headache Disorders (ICHD-3 guidelines) sets out the criteria needed to diagnose Tolosa Hunt syndrome. Diagnoses are usually made by ruling out other possible causes and illnesses. Some requirements are made of the following symptoms:⁴

• Severe, one sided pain near the eye which can last a couple weeks if left untreated
• Symptoms usually improve with a few days when treated with medication like corticosteroids 
• The muscles of the eye that controls movement becomes weaker which restricts movement and can cause double vision 
• There is no other suggestions of another cause of the pain after tests have been run 

The Role of Imaging in Forming a Diagnosis 

To confirm a diagnosis, different forms of imaging are used to assess if there is any inflammation and to rule out any other possible causes such as tumours. Magnetic resonance imaging (MRI) is used to find any inflammation near the eye and surrounding tissues. This is the main diagnostic imaging used to find a diagnosis. CT scans can also be done to look for any structural abnormalities that may show signs of THS or it can lead to alternative diagnoses like a fracture. 

Laboratory Tests Role in Making a Diagnosis

Laboratory tests are also done to help rule out other disorders that have similar symptoms to THS.⁵ These can be infections, cancer or autoimmune illnesses. The following can be done:

• Blood tests can be done to test for inflammatory markers that can cause inflammation typically seen in THS
• Blood tests can also be used to test for autoimmune disorders that have similar symptoms to THS 
• Infections like tuberculosis and fungal/bacterial infections can impact the brain and eyes causing symptoms that are commonly seen in THS
• A lumbar puncture can be done which involves taking fluid from the spine or brain to test for any infections or inflammation, for example meningitis can be present
• Different cancers are checked for as they can cause pain around the eyes and restrict movement. To do this a biopsy can be taken or bloods can be drawn

Corticosteroids as a Treatment for THS

The standard treatment for THS are corticosteroids. They work by decreasing the inflammation around the sinus which generally relieves most symptoms. Taking this can help provide relief within a couple of days. 

There is inflammation around the cavernous sinus in THS, this adds stress and pressure onto the nerves that helps the eye to move. This causes pain and double vision. Corticosteroids help to decrease the swelling present and help the nerves to move normally by controlling the immune system.⁶ This also stops more damage from occurring by stopping further inflammation. 

Side Effects of Using Corticosteroids

Common side effects of taking corticosteroids long-term include:

• High blood pressure
• Changes in mood, becoming more anxious
• Difficulty in sleeping 
• Weight gain 
• Weaker immune system
• Weaker bones 

To manage these symptoms, it is encouraged to use corticosteroids as a short-term treatment, and gradually decrease the dose to prevent withdrawal symptoms. Whilst taking this medication, your healthcare team may decide it is best to take vitamin D and C to help stop any damage to the bones. It is important to regularly check blood pressure and blood sugar levels so that any changes can be detected early. 

Alternative Treatments for Tolosa Hunt Syndrome

Although corticosteroids are the go to treatment option, they are not always the most effective. Sometimes there are too many side effects of THS returns frequently. When this is the case, alternative treatment options are considered.

Immunosuppressive Agents

Immunosuppressive agents work by stopping the immune system from working properly, it shuts it down to reduce inflammation and the heightened immune response seen in THS ⁷. They are used when corticosteroids don’t work, when symptoms flare up again, when the doses start to reduce and if the side effects of these steroids are too severe. The most common immunosuppressants are:

• Methotrexate - helps to decrease inflammation gradually over time
• Cyclophosphamide - stronger type used for THS that continually reoccurs
• Azathioprine - used when there are relapses

Biologics 

These drugs target specific areas of the immune system to decrease inflammation. This is much more targeted and precise compared to the normal immunosuppressants. They are used when both corticosteroids and immunosuppressants do not work and when an autoimmune disorder is suspected. Most common biologic treatments used are:⁸

• Anti-TNF agents - they block tumor necrosis factor (TNF) which causes the immune system to overreact 
• Rituximab - focuses on B cells (type of immune cell) which helps to control inflammation

Radiotherapy

Radiotherapy is not a common option and only used when usual treatments fail and when imaging shows a lesion in the cavernous sinus.⁹ It may also be used if there is a suspected tumor that could be causing the symptoms. There are some risks and benefits to radiotherapy as outlined below:

• Can help reduce inflammation when other treatments fail
• May be effective in recurrent THS
• Potential nerve damage – radiation can affect surrounding healthy nerves
• Tissue scarring, which may cause long-term issues

Long-term Management of Tolosa Hunt Syndrome

Tolosa-Hunt Syndrome (THS) is a rare but treatable condition that causes severe eye pain and problems with eye movement.¹⁰ The good news is that most people recover well with treatment, usually within a few weeks. However, some may experience relapses, meaning symptoms can return over time.

Typical Course of the Disease and Expected Outcomes

• Rapid improvement: Once treatment with corticosteroids begins, most people feel better within a few days
• Full recovery: Eye movement usually returns to normal within a few weeks
• Long-term outlook: Some patients recover completely and never have another episode. Others may experience flare-ups over the years

How Often Do Relapses Happen?

• About 30–50% of people with THS may have another episode at some point
• There is no clear pattern—some people have only one episode, while others may have multiple recurrences
• Relapses may happen months or even years later

What Can You Do to Help?

• Follow treatment plans carefully – Always take medications as prescribed and never stop suddenly
• Report symptoms early – If pain or vision problems return, seek medical advice right away
• Manage stress – Stress may not cause THS, but it can weaken the immune system and make symptoms worse
• Maintain a healthy lifestyle – Eating well, staying active, and avoiding smoking can support overall immune health

Summary 

Tolosa-Hunt Syndrome (THS) is a rare but treatable condition that causes severe eye pain and movement difficulties due to inflammation near the eye. Corticosteroids are the first-line treatment, providing rapid relief, but some patients may require alternative therapies like immunosuppressants or biologics if relapses occur. In rare cases, radiotherapy or surgery may be considered.

Long-term management focuses on monitoring for relapses, adjusting treatments as needed, and maintaining a healthy lifestyle to reduce flare-ups. With early diagnosis and proper treatment, most people recover well and can lead normal lives.