Case report of an alleviation of pain symptoms in hypnic headache via greater occipital nerve block

Role of Greater Occipital Nerve Block in Headache Disorders: A Narrative Review

Background

The proximity of sensory neurons in the upper cervical spinal cord to the trigeminal nucleus caudalis (TNC) neurons and the convergence of sensory input to TNC neurons from both cervical and trigeminal fibers underscore the rationale of using greater occipital nerve block (GON-block) for acute and preventive treatment in various headache disorders.

Objective

The aim of this study was to critically review the existing literature regarding the safety and efficacy of GON-block in various headache disorders.

Methods

We searched the eligible studies in English by searching in PubMed till December 31, 2020 for randomized controlled trials (RCTs), observational studies, open-label studies, case series, and case reports on the efficacy and the safety of GON-block for the treatment of headache disorders using the keywords "greater occipital nerve block", "headache" and "treatment". Studies using combination of GON-block and other peripheral nerve blocks (PNBs) and C2/C3 blocks were excluded.

Results

Seventy-two eligible studies were reviewed. Based on RCTs and open-label studies, good evidence of the efficacy of GON-block was found for migraine, cluster headache (CH), post-dural puncture headache (PDPH), cervicogenic headache (CGH), and occipital neuralgia (ON). The analgesic effect of GON-block outlasted its anesthetic effect by days to weeks. Evidence for acute and short-term (transitional) treatment was more robust than for long-term prevention. GON-block was found to be safe and the treatment-emergent adverse effects (TEAEs) were generally mild and transient.

Conclusion

GON-block is a useful modality of treatment in various headache disorders because of many attractive features such as its early effect in reducing the severity of pain, sustained effect following a single injection, easy technique, minimum invasiveness, minimum TEAE, no drug-to-drug interactions, and negligible cost.

Case report of hypnic headache: a rare headache disorder with nocturnal symptoms

Background

Headache is one of the commonest complaints reported to physicians worldwide. Yet, arriving at the proper diagnosis can be a challenge in many patients. Although most headaches belong to common categories of migraine and tension-type headache, which are diagnosed and managed relatively easily, several uncommon headache disorders can lead to delays in diagnosis. Certain medications are more efficacious than others in managing these headache disorders, hence establishing the correct diagnosis is of paramount importance.

Case presentation

An 86-year-old female presented with chronic daily headache of 1 year duration. Her headaches were exclusively nocturnal and woke her up daily around midnight. Clinical examination was unremarkable. All basic investigations were normal. Subsequent gadolinium enhanced Magnetic Resonance Imaging (MRI) brain did not show any significant pathology. There was no satisfactory response to paracetamol, diclofenac sodium, mefenamic acid, tramadol, flunarizine and sodium valproate. Indomethacin was started with the provisional diagnosis of hypnic headache. There was absolute response by day 3 of indomethacin. She remains headache free on low dose indomethacin maintenance at 1 year after the diagnosis.

Conclusion

Better understanding of uncommon headache syndromes can help in early diagnosis and appropriate treatment. Hypnic headache should be considered in the differential diagnosis of chronic daily headaches, especially when nocturnal and occurs during sleep.