Cluster headache associated with oculomotor nerve palsy: A case report and review of literature.

Cluster headaches are a series of short, excruciating, and unilateral pain that happens for a short period at a time over days, weeks, or months and may awake people from sleep. It is situated behind, in, or around one eye only with possible radiation to the forehead at the same side. Cluster headache is characterized by many ocular features. However, extraocular muscle involvement is unusual in this type of headache. We present a case of chronic cluster headache associated with diplopia due to oculomotor nerve palsy in a 24-year-old man, which responded successfully to oral steroid. This presentation is rare. Therefore, ophthalmologists and neurologists should consider it in their list of a differential diagnosis. A short course of oral prednisolone has a role in the management of patients in such cases. Copyright:

Introduction

Cluster headache is a rare and debilitating form of headache that predominantly occurs in men.[1] The main feature is severe unilateral pain in or around one eye accompanied by autonomic symptoms like lacrimation. The typical attacks are recurrent, and each can last from minutes to 3 h.[2] The ocular symptoms related to cluster headache include lacrimation, conjunctival injection, ipsilateral rhinorrhea, and Horner's syndrome.[1]

Factors that precipitate cyclic cluster headaches include medications (nitroglycerin and histamine), alcohol, environmental changes, circadian periodicity, shifting of sleep pattern to nonrapid eye movement (non-REM) from REM, and alteration in psychological or physical activities.[1]

Extraocular muscle involvement is unusual in cluster headache.[3] The involvement of the oculomotor nerve during attacks leads to paralysis of the oculomotor muscles resulting in ptosis, outward and downward globe deviation, mydriasis, and relaxation of accommodation.[4]

Case Report

A 24-year-old male patient, medically free, nonsmoker, and social drinker, presented with binocular diplopia and brief episodes of severe headache for 1 week. The patient complained of excruciating and restlessness episodes of pain (about 4–6 times a day with each lasting 30–120 min on average) in, behind, and around the right eye. The pain was stabbing in nature, not responding to painkillers, affected only the right side, and associated with ipsilateral eye redness, excessive tearing, and rhinorrhea. Moreover, the patient complained of episodes of wakening up at night due to severe pain.

Headaches were exaggerated with drinking alcohol and alleviated with extreme pressure on the eye. He denies having an aura, any family history of headaches, or previous history of diplopia. Further, he complained of episodes of periodic, brief, and excruciatingly severe headaches over the last 2 years, separated by pain-free periods lasting for months. He did not visit any neurologists or take any medications apart from painkillers.

Upon examination, his best-corrected visual acuity was 20/20 in both eyes. Ocular motility showed normal abduction and limited adduction, elevation, and depression along with mydriasis and mild ptosis in the right eye, while the left eye was normal [Figure 1]. Anterior and posterior segments and intraocular pressure were within normal limits with no evidence of optic disc swelling in both eyes. Apart from the right third nerve palsy, there were no other ocular or neurological features.

Figure 1

Nine cardinal positions of gaze with normal abduction and limitation of adduction, elevation, and depression in the right eye along with pupillary dilatation (arrow) and ptosis. Ductions in the left eye appear normal

Brain magnetic resonance imaging with contrast, magnetic resonance angiography, and computed tomography angiography were unremarkable. Furthermore, complete blood count, erythrocyte sedimentation rate, C-reactive protein, fasting blood sugar, glycated hemoglobin, thyroid function test, kidney function test, B12 level, and blood pressure were all within normal limits.

After neurological consultation, the patient was diagnosed with cluster headache associated with oculomotor nerve palsy. He was encouraged to close the affected eye and commenced on 70 mg (1 mg/kg) of oral prednisolone for 1 week. He showed a gradual improvement of ocular symptoms besides fewer attacks, shorter periods, and lower intensity of headaches during the 1st week. Later, the dose was reduced by 10 mg per week. During the treatment period with oral steroid, oculomotor nerve palsy resolved without recurrence of cluster headaches [Figure 2]. After completing the treatment with oral prednisolone, the patient was started on verapamil 80 mg three times a day. No episodes of cluster headaches were reported for about 8 months.

Figure 2

Three months following the headache. The nine cardinal positions of gaze with full ocular motility in both eyes and complete resolution of third nerve palsy in the right eye

Discussion

Cluster headache is one of the primary headache disorders called trigeminal autonomic cephalalgias. It is characterized by severe unilateral series of pain lasting between 15 and 180 min along with the distribution of the trigeminal nerve.[2] These attacks occur within a specific time ranges from weeks to months with asymptomatic remission periods.[2] Young age (20–40 years), male gender, smoking, alcohol consumption, and family history are considered risk factors for cluster headache.[1]

The pain is usually severe and described as “boring” or “piercing” with activation of the parasympathetic pathways leading to rhinorrhea, ptosis, miosis, lacrimation, conjunctival injection, and eyelid swelling.[23] The differential diagnosis for cluster headache includes trigeminal neuralgia, migraine, temporal arteritis, chronic paroxysmal hemicrania, and Raeder's paratrigeminal syndrome.[1] In our case, the headache features go with the cluster headache criteria.[2] However, the presence of oculomotor nerve palsy makes it challenging. Cluster headache with ophthalmoplegia is a rare presentation. Nonetheless, few cases have been prescribed with sixth[3] and third cranial nerve palsies.[56]

Like cluster headache, other abnormalities can present with both pain and third nerve palsy such as recurrent ophthalmoplegic neuropathy, Tolosa–Hunt syndrome, vascular lesions, and inflammatory diseases.[2] However, the clinical picture along with the history and normal investigations make cluster headache the most probable diagnosis.

The actual mechanism of cluster headaches is not known definitely and is still under investigation. It is proposed that the vasodilation of the cerebral blood vessels, due to the high blood levels of histamine during the attack, triggers cluster headache. In addition, alcohol, nitroglycerin preparations, and high altitudes trigger cluster headaches as they all cause vasodilation.[1] Oculomotor nerve involvement causes dysfunction of the somatic extraocular muscles or autonomic muscles (pupillary sphincter and ciliary muscle). It may present as complete or partial palsy with variable limitation of supraduction, infraduction, adduction, and variable ptosis. Both pictures can present with or without pupillary dysfunction.[4]

One theory attributes the direct involvement of the oculomotor nerve during the attacks to the swelling of the internal carotid artery in the cavernous sinus. Similarly, Horner syndrome occurs due to the involvement of sympathetic nerves that run alongside the swollen internal carotid artery.[3]

Although abortion of the attack is possible with the application of high-flow oxygen or subcutaneous sumatriptan, this only provides relief of symptoms, and patients still require prophylactic medications to terminate the cycle and prevent future attacks. Verapamil and lithium are useful prophylactic agents.[78] Corticosteroids also have a role in the management of cluster headache.[9] It is proposed that its effect in stimulating endogenous opiate and reduction of histamine levels in plasma in addition to its potent anti-inflammatory effects are behind its ability in relieving headaches.[78]

A recent study found a significant increase in calcitonin gene-related peptide (CGRP) levels along with a decrease in melatonin levels during cluster headache episodes. These findings reflect the possibility of trigeminal activity and hypothalamic dysfunction, respectively.[10] The role of corticosteroids in relieving cluster headache is linked to its ability to lowering the CGRP and elevation of melatonin levels.[10]

Conclusions

Extraocular muscle involvement is an exceptional presentation of cluster headache. Thus, ophthalmologists and neurologists should be aware of this. A short course of oral steroid is effective in managing third nerve palsy correlated with cluster headache. Moreover, it has a role in alleviating pain and preventing further attacks in patients with cluster headache. These observations reflect the possibility of an underlying inflammatory mechanism. Oral prednisolone followed by low-dose verapamil (240 mg/day) is sufficient as a prophylactic treatment for patients with cluster headaches.

Ethics approval and patient consent

Written informed consent was obtained from the patient.

Consent for publication

Written informed consent was obtained from the patient to publish this case report along with his images.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.