The Potential Roles of Cervical Plexus Abnormalities in Occipital Neuralgia: An Anatomic Variant Explored

Occipital neuralgia (ON) is a condition defined as a headache characterized by paroxysmal burning and stabbing pain located in the distribution of the greater occipital nerve (GON), lesser occipital nerve (LON), or third occipital nerves (TON). This condition can be severely impairing in symptomatic patients and is known to have numerous etiologies deriving from various origins such as trauma, anatomical abnormalities, tumors, infections, and degenerative changes. This study reports four cases of a previously undescribed anatomical variant in which the (spinal) accessory nerve (SAN) fuses with the LON before piercing the sternocleidomastoid (SCM). The fusion of these two nerves and their route through the SCM points to a potential location for nerve compression within the SCM and, in turn, another potential source of ON. This anatomical presentation has clinical significance as it provides clinicians with another possible cause of ON to consider when diagnosing patients who present with complaints of a headache. Additionally, this study explores the prevalence of piercing anatomy of the LON and GAN and discusses their clinical implications.

Decompression of the Greater Occipital Nerve for Occipital Neuralgia and Chronic Occipital Headache Caused by Entrapment of the Greater Occipital Nerve

Background Chronic entrapment of the greater occipital nerve (GON) can not only manifest in typical stabbing pain of occipital neuralgia (ON) but also lead to continuous ache and pressure-like pain in the occipital and temporal areas. However, the effect of GON decompression on these symptoms has yet to be established. We report the follow-up results of GON decompression in typical cases of ON and chronic occipital headache due to GON entrapment (COHGONE). Methods A 1-year follow-up study of GON decompression was conducted on 11 patients with typical ON and 39 COHGONE patients with GON entrapment. The degree of pain reduction was analyzed using the numerical rating scale-11 (NRS-11) score and percent pain relief before and 1 year after surgery. A success was defined by at least a 50% reduction in pain measured via NRS-11 during the 12-month follow-up. To assess the degree of subjective satisfaction, a 10-point Likert scale was used. Postoperative outcome was also evaluated using the Barrow Neurological Institute (BNI) pain intensity score. The difference in GON decompression between the patients with typical ON and those with COHGONE was studied. Results GON decompression was successful in 43 of 50 patients (86.0%) and percent pain relief was 72.99 ± 25.53. Subjective improvement based on a 10-point Likert scale was 7.9 ± 2.42 and the BNI grade was 2.06 ± 1.04. It was effective in both the ON and COHGONE groups, but the success rate was higher in the ON group (90.9%) than in the COHGONE group (84.6%), showing statistically significant differences in the results based on average NRS-11 score, percent pain relief, subjective improvement, and BNI grades (p < 0.05, independent t-test). Conclusion GON decompression is effective in chronic occipital headache and in ON symptoms induced by GON entrapment.

Bilateral Occipital Neuralgia in a Patient with Neurofibromatosis Type 1: A Case Report

Plexiform neurofibromas (PNFs) represent an uncommon variant (30%) of neurofibromatosis type 1 (NF-1), in which neurofibromas arise from multiple nerves as bulging and deforming masses involving connective tissue and skin folds. We report the case of a 17-year-old man with known NF-1 presenting with bilateral occipital neuralgia that began in his late adolescence. His chief complaint was radiating pain in the occiput induced by protective helmet wear when riding alpine skiing. Craniofacial magnetic resonance imaging (MRI) confirmed the presence of fusiform masses arising from the bilateral greater occipital nerves. Histopathological examination of the biopsy samples showed PNFs. After surgical treatment, the patient's symptoms completely improved. Unlike cutaneous neurofibromas, PNFs have different clinical characteristics and have the risk of malignant mutations. Correct diagnosis and adequate surgical treatment are necessary for PNFs.

A.5 Identification of predictors of response to Erenumab in episodic and chronic migraine in a cohort of patients: a preliminary analysis

Background: Erenumab is an antibody anti-calcitonin gene related peptide (CGRP) receptor approved for the treatment of episodic (EM) and chronic migraine (CM). In this study, we aimed to identify the predictors of response to the treatment. Methods: This is an ongoing retrospective cohort study of 120 patients (49 with cervicalgia) with EM or CM treated with Erenumab. The first endpoint was to identify the success rate of this treatment (at least 50% reduction in monthly migraine days during the third month of the treatment). The second endpoint was to identify the predictors of response to Erenumab treatment. Results: Seventy one percent of patients achieved a favorable response (P-value<0.001) to Erenumab. Patients with cervicalgia showed a lower treatment success rate (21.1% with vs 40.8% without cervicalgia) while patients without cervicalgia showed a higher treatment success rate (78. 9% without vs 59.2% with cervicalgia) with a P-value of 0.025 and an odd ratio of 0.388 (95% CI 0.174-0.869, P-value=0.021). A similar trend was observed in patients with occipital neuralgia and obesity (P-value<0.08). Conclusions: The preliminary analysis of this study demonstrates that cervicalgia (and to a lesser extend occipital neuralgia and obesity) is a negative predictor of response to Erenumab in patients with migraine.

An osteopathic approach to occipital neuralgia and tinnitus

Eye pain and ringing in the ear are non-specific symptoms commonly evaluated by primary care physicians and specialists alike. The differential diagnosis for these symptoms is broad and includes musculoskeletal, ophthalmologic and neurologic considerations. Careful consideration of the differential diagnosis should include acute, potentially life-threatening pathologies such as glaucoma or intracranial masses, as well as common pathologies, including cervicalgia, headache variants (migraine, tension) and acoustic neuroma. This report describes a patient with eye pain caused by occipital neuralgia and tinnitus. Correcting the somatic dysfunctions found in the head, cervical, thoracic and rib regions with osteopathic manipulative treatment resolved the occipital neuralgia and the tinnitus for this patient. Thus, osteopathic manipulative treatment should be considered for conservative management of occipital neuralgia and tinnitus.

Could a Simple Nerve Block be Considered as a Treatment Option for Occipital Neuralgia with Both Short-Term and Long-Term Effects?

Objective: The study aims to show both the short- and long-term treatment outcome of occipital nerve block (ONB) patients with occipital neuralgia (ON).Methods: Patients who visited our hospital between 2013 and 2020 were reviewed retrospectively. Patients were excluded if the medical records were incomplete, if they had received a cervical operation, if they had a traumatic event prior to the symptom onset, or if the follow-up period was less than 3 months. ONB targeted the greater occipital nerve, the lesser occipital nerve or both. Short term follow-up period was defined as 3 months and long term was defined as 12 months. Injection consisted of a mixture of triamcinolone acetonide, lidocaine, and normal saline. Visual analogue scale (VAS) was recorded and compared before and during the follow-up to period to assess treatment outcome.Results: Clinical charts of 309 candidates were reviewed and 72 patients were excluded, making it 237 patients. VAS scores significantly decreased in both 3-month follow-up (from 7.20±0.94 to 3.48 ±1.66, p<0.05) and after 1 year follow-up (from 7.20±0.94 to 2.71±1.07, p<0.05). Only 8 patients (3.3%) were refractory to ONB and the procedure was found to be relatively safe since only 2 patients (0.8%) showed transient side effects.Conclusion: There are many treatment options for ON. However, from the results of our study, conservative treatment via ONB may have sufficient effect in controlling symptoms of ON in both short and long term.