High-Resolution Ultrasound for Diagnostic Assessment of the Great Auricular Nerve – Normal and First Pathologic Findings

Abstract

Purpose: The great auricular nerve (GAN) is a sensory branch of the superficial cervical plexus. While its blockade is an established procedure, little is known about the ultrasound appearance of pathologic conditions of the GAN itself. We, therefore, aimed to evaluate the possibility of the visualization and diagnostic assessment of the GAN along its entire course by means of high-resolution ultrasound (HRUS).

Materials and Methods: To assess the feasibility of visualization, we performed HRUS with an 18 MHz probe, HRUS-guided, fine-needle ink markings and consecutive dissection in six anatomical specimens. Then, we measured the diameter of the GAN in healthy volunteers and finally performed a retrospective review of patients referred for HRUS examinations because of pain within GAN territory between August 1, 2012 and August 1, 2013.

Results: The GAN was clearly visible with HRUS from its formation to the final branches, and was marked successfully on both sides in all anatomical specimens (n = 12). The mean average in-vivo was 0.14 cm ± 0.03 (range 0.08 – 0.2). Seven cases of patients with GAN pathologies of various origins (idiopathic, traumatic, tumorous and iatrogenic) were identified, of which 6 were visible on HRUS and all of which could be confirmed by complete resolution of symptoms after selective HRUS-guided GAN block.

Conclusion: This study confirms the reliable ability to visualize the GAN with HRUS throughout its course, both in anatomical specimens and in vivo. The provided cases show that pathologies of the GAN seem to have a variety of causes and may not be rare. We, therefore, encourage the use of HRUS in patients with unclear pain in the auricular, periauricular and posterior-lateral head.

Zusammenfassung

Ziel: Der Nervus auricularis magnus (GAN) ist ein sensibler Ast des Plexus cervicalis superficialis. Während seine Blockade eine etablierte Methode ist, ist wenig bekannt über die sonografische Darstellung pathologischer Zustände des GAN selbst. Ziel dieser Studie war es, Visualisierbarkeit und diagnostisches Potential des hochauflösenden Ultraschalls (HRUS) im gesamten Verlauf des GAN zu evaluieren.

Material und Methoden: Zur Klärung der Visualisierbarkeit wurde eine HRUS-gezielte Markierung der GAN und anschließende Sektion in sechs anatomischen Präparaten durchgeführt. Danach wurde der Durchmesser des GANs bei 10 gesunden ProbandInnen vermessen. Zusätzlich erfolgte eine retrospektive Analyse der PatientInnen, die zwischen 1. August 2012 und 1. August 2013 aufgrund von Schmerzen im Bereich des GAN untersucht wurden.

Ergebnisse: Der GAN konnte von seiner Formierung bis in die Endäste verfolgt werden und wurde in allen anatomischen Präparaten erfolgreich markiert (n = 12). Der mittlere Durchmesser in-vivo war 0,14 cm ± 0,03 (0,08 – 0,2 cm). Sieben PatientInnen mit GAN-Pathologien unterschiedlicher Genese wurden identifiziert (idiopathisch, traumatisch, tumor-assoziiert und iatrogen), von denen 6 mittels HRUS visualisiert werden konnten und alle durch vollständige Remission der Schmerzen nach HRUS-gezielter, selektiver Blockade des GAN bestätigt werden konnten.

Schlussfolgerungen: Diese Studie bestätigt die Visualisierbarkeit des GAN sowohl im anatomischen Präparat als auch in vivo. Die präsentierten Fälle zeigen, dass das breite Spektrum möglicher Pathologien des GAN wesentlich häufiger sein könnte als angenommen. Wir empfehlen eine HRUS-Abklärung bei PatientInnen mit Schmerzen im Bereich des Ohres, periaurikulär und poster-lateralen Kopfes.

Key words

head/neck - ear - great auricular nerve - neuroma - neuropathic pain

• References

• 1 Becser N, Bovim G, Sjaastad O. Extracranial nerves in the posterior part of the head. Anatomic variations and their possible clinical significance. Spine (Phila Pa 1976) 1998; 23: 1435-1441
• 2 Standring S. Gray´s Anatomy. 40th ed. Churchill Livingstone Elsevier; 2008
• 3 Sand T, Becser N. Neurophysiological and anatomical variability of the greater auricular nerve. Acta Neurol Scand 1998; 98: 333-339
• 4 George M, Karkos PD, Dwivedi RC et al. Preservation of greater auricular nerve during parotidectomy: Sensation, quality of life, and morbidity issues. A Systematic Review. Head Neck 2013; DOI: 10.1002/hed.23292.
• 5 Li Y, Zhang J, Yang K. Evaluation of the efficacy of a novel radical neck dissection preserving the external jugular vein, greater auricular nerve, and deep branches of the cervical nerve. Onco Targets Ther 2013; 6: 361-367 DOI: 10.2147/OTT.S43073.
• 6 Herring AA, Stone MB, Frenkel O et al. The ultrasound-guided superficial cervical plexus block for anesthesia and analgesia in emergency care settings. Am J Emerg Med 2012; 30: 1263-1267 DOI: 10.1016/j.ajem.2011.06.023.
• 7 Selekler M, Kutlu A, Ucar S et al. Immediate response to greater auricular nerve blockade in red ear syndrome. Cephalalgia 2009; 29: 478-479 DOI: 10.1111/j.1468-2982.2008.01756.x.
• 8 Suresh S, Bellig G. Regional anesthesia in a very low-birth-weight neonate for a neurosurgical procedure. Reg Anesth Pain Med 2004; 29: 58-59
• 9 Neopane A, Upadhyaya B, Dungana S et al. Study of patients presenting with symptoms of peripheral neuropathy and thickened greater auricular nerve. Kathmandu Univ Med J (KUMJ) 2003; 1: 3-7
• 10 Lynch P. Greater auricular nerve in diagnosis of leprosy. Br Med J 1978; 2: 1340
• 11 Ramesh V, Jain RK, Avninder S. Great auricular nerve involvement in leprosy: scope for misdiagnosis. J Postgrad Med 2007; 53: 253-254
• 12 Ng AK, Page RS. Greater auricular nerve neuropraxia with beach chair positioning during shoulder surgery. Int J Shoulder Surg 2010; 4: 48-50 DOI: 10.4103/0973-6042.70824.
• 13 Park TS, Kim YS. Neuropraxia of the cutaneous nerve of the cervical plexus after shoulder arthroscopy. Arthroscopy 2005; 21: 631 DOI: 10.1016/j.arthro.2005.02.003.
• 14 Vorobeichik L, Fallucco MA, Hagan RR. Chronic daily headaches secondary to greater auricular and lesser occipital neuromas following endolymphatic shunt surgery. BMJ Case Rep 2012; DOI: 10.1136/bcr-2012-007189.
• 15 Tubbs RS, Salter EG, Wellons JC et al. Landmarks for the identification of the cutaneous nerves of the occiput and nuchal regions. Clin Anat 2007; 20: 235-238 DOI: 10.1002/ca.20297.
• 16 Christ S, Kaviani R, Rindfleisch F et al. Brief report: identification of the great auricular nerve by ultrasound imaging and transcutaneous nerve stimulation. Anesth Analg 2012; 114: 1128-1130 DOI: 10.1213/ANE.0b013e3182468cc1.
• 17 Thallaj A, Marhofer P, Moriggl B et al. Great auricular nerve blockade using high resolution ultrasound: a volunteer study. Anaesthesia 2010; 65: 836-840 DOI: 10.1111/j.1365-2044.2010.06443.x.
• 18 Cho JC, Haun DW, Kettner NW. Sonographic evaluation of the greater occipital nerve in unilateral occipital neuralgia. J Ultrasound Med 2012; 31: 37-42
• 19 Bodner G, Harpf C, Gardetto A et al. Ultrasonography of the accessory nerve: normal and pathologic findings in cadavers and patients with iatrogenic accessory nerve palsy. J Ultrasound Med 2002; 21: 1159-1163
• 20 Bodner G, Bernathova M, Galiano K et al. Ultrasound of the lateral femoral cutaneous nerve: normal findings in a cadaver and in volunteers. Reg Anesth Pain Med 2009; 34: 265-268 DOI: 10.1097/AAP.0b013e31819a4fc6.
• 21 Iida S, Shirasuna K, Kogo M et al. Amputation neuroma following radical neck dissection--report of 3 cases. J Osaka Univ Dent Sch 1995; 35: 1-4
• 22 Ha EJ, Baek JH, Lee JH et al. Characteristic ultrasound feature of traumatic neuromas after neck dissection: direct continuity with the cervical plexus. Thyroid 2012; 22: 820-826 DOI: 10.1089/thy.2012.0092.
• 23 Janis JE, Hatef DA, Ducic I et al. The anatomy of the greater occipital nerve: Part II. Compression point topography. Plast Reconstr Surg 2010; 126: 1563-1572 DOI: 10.1097/PRS.0b013e3181ef7f0c.
• 24 Busch V, Frese A, Bartsch T. The trigemino-cervical complex. Integration of peripheral and central pain mechanisms in primary headache syndromes. Schmerz 2004; 18: 404-410 DOI: 10.1007/s00482-004-0347-x.