Short-lasting Unilateral Neuralgiform headache attacks with Conjunctival injection and Tearing (SUNCT) is a primary headache syndrome. It is a part of Trigeminal Autonomic Cephalgias along with Cluster Headache and Paroxysmal Hemicranias. The headache has characteristic unilateral pain and associated ipsilateral Autonomic symptoms i.e. Conjunctival Tearing.
- Location of pain
- Character, Duration, and Frequency of pain
- SUNCT Syndrome and SUNA
- When to consult the doctor?
Location of pain
Character, Duration, and Frequency of pain
The headache attacks occur in three forms: single stabs, a group of stabs, and a long duration stab with no pain-free episode in between. In single and grouped stabs, there are pain-free episodes where the pain touches the base-line and then spikes up with stabbing. The frequency of attacks ranges from 2 to around 600 attacks in a day with each attack lasting for about a few seconds to a few minutes.
- Unilateral Headache
- Ipsilateral Autonomic Symptoms in areas supplied by the division of the Trigeminal nerve.
- Conjunctival Tearing
- Migraine like symptoms
- Reduced sensations and Numbness on the Ipsilateral side
- Eyelid edema
- Forehead and facial sweating and flushing
- A sensation of fullness in the ear
There are several times that SUNCT is idiopathic and is included in Trigeminal Autonomic Cephalgias. Some case studies revealed that it was due to:
- Intracranial lesions compressing the nerve roots.
- Pituitary Adenomas
- Lesions in Posterior Cranial Fossa
- Cerebellopontine Arteriovenous Malformation
- Autonomic symptoms may present because of the central disinhibition of the Autonomic reflex of the Trigeminal nerve by the hypothalamus.
It can be triggered by doing normal day to day tasks, such as:
Washing, Brushing, Chewing, Talking, Shaving, Brushing the hair, Exposure to sunlight, and Neck movement. An individual can have spontaneous attacks as well, without any sort of triggers.
SUNCT Syndrome in Females
There is a predisposition of SUNCT syndrome in females.
SUNCT Syndrome and SUNA
SUNA- Short-lasting Unilateral Neuralgiform headache attacks with cranial Autonomic features are known to include SUNCT Syndrome since patients with SUNA have all the symptoms of SUNCT other than Conjunctival Tearing. The frequency and duration of attacks along with the location of pain transpired very much like that of SUNCT Syndrome.
- A Neurological examination does not form a valid diagnosis but some findings can help form a differential diagnosis. Ipsilateral Parasthesia, Loss of sensation to pinprick, numbness, and pins and needles sensation are a few of these.
- Other than that an MRI can be done to rule out any other suspected findings and to see any structure is compressing the Trigeminal nerve root, this can also formulate a diagnosis for Trigeminal Neuralgia. Functional MRI has shown hypothalamic activation during an attack.
- There is no definitive treatment for SUNCT Syndrome but for an acute attack, Intravenous Lidocaine can help decrease the frequency.
- Botulinum Toxin around the symptomatic areas has also proved relief.
- Nerve block using thermocoagulation, gamma knife neurosurgery, alcohol, or microvascular decompression at Gasserian ganglion or first division of Trigeminal nerve can provide temporary or permanent relief.
- Hypothalamic stimulation has also given persistent relief to some patients.
When to consult the doctor?
If you start having frequent attacks and ipsilateral autonomic signs you should consult the doctor as soon as possible. As the frequency of attacks is high in SUNCT Syndrome and forces the patient (in undiagnosed cases) to take painkillers. This can develop another condition, Medication-overuse headache.
Pain is typically felt on one side of head, behind and around the eyes and in temples. Pain feels like stabs mostly and is pinching in character.
There is no proper cause of SUNCT syndrome, some researches have shown hypothalamic hyperactivity during an attack.
It is considered as a subset of SUNA as the symptoms and pattern of attacks in both is similar the only difference is of Conjunctival Injection and tearing that is associated with SUNCT Syndrome.
Hypothalamic stimulation has given complete and permanent relief to some patients.