Facial Pain – a Diagnostic Challenge

CLINICAL

Facial pain – A diagnostic challenge

Geoffrey Quail

Background Facial pain Pathological states that Recurrent unilateral headache is a simulate pain of dental Facial pain is one of the most common origin neurological complaints together with common complaint seen in general headache, and back and abdominal practice and is the reason for referrals to Localisation of the site where the pain pain. In most cases, the aetiology can specialists. It may be an early symptom originates is frequently difficult as there is be ascertained from a detailed history of underlying neurological or other considerable variation in, and overlapping and examination. However, the source systemic disturbance, but facial pain of, sensory nerve distribution in the face. of pain may be obscure as oral and facial often results from disorders associated Referred pain is common in the head and structures frequently have multiple with one or more cranial nerves. A neck, especially in the region of the ear.2 innervations, and referred pain to the ear recent study showed that in 87% of Here, pain may arise from the ear itself, is common. The oral cavity, particularly cases, facial pain was due to dental or be referred from an ulcer at the base dental structures, is the most common causes or diseases of the oral mucosa.1 of the tongue (via the auricular temporal source of facial pain; patients should be Causes of facial pain are listed in Box 1. branch of the mandibular nerve)3 or referred for a dental assessment when As with other neurological complaints, from a degenerative lesion of the upper pain is precipitated or aggravated by a complete history and clinical cervical vertebrae (via the greater or lesser thermal change or eating. examination, including of the cranial occipital or great auricular nerves [cervical Objective nerves, will reveal the diagnosis in the nerves C2 and C3]). The lesion must be majority of cases. A history of pain with on the side where the pain is experienced The aim of this article is to provide a thermal change or on biting suggests a if the pain is unilateral4 or, if it is bilateral, framework for assessment of patients dental cause. In these cases, examination it is likely to be due to systemic disease presenting with facial pain. usually reveals an oral lesion. However, a (eg chronic meningitis) or psychogenic in dental opinion should be obtained when origin. Discussion in doubt. Maxillary sinusitis This paper examines the aetiology, diagnosis and management of non- Acute maxillary sinusitis may present dental/oral mucosa causes of facial pain. Box 1. Causes of facial pain as pain in the region of the upper molar teeth, which may also be tender • Dental, oral, pharyngeal: –– Infections to percussion. Chronic sinusitis can –– Trauma result from infection, allergy or airway –– Neoplasm abnormality. It is often characterised by –– Other inflammatory conditions nasal obstruction and discharge, malaise • Facial bone disease and halitosis, the latter due to mouth • Temporomandibular joint dysfunction breathing. Pain in the malar region can • Salivary gland lesions be diffuse and be associated with frontal • Paranasal sinus disease headache and tenderness over the • Neurological disorders sinus and upper molar teeth. It may be • Vascular disorders aggravated by running and bending over. • Psychogenic disorders Sinusitis can be a sequel to dental pulpitis

of an upper molar if periapical infection the superior cerebellar, compressing the is an open microsurgical retro-sigmoid spreads to the floor of the sinus. trigeminal nerve trunk, which causes craniotomy to access the trigeminal nerve demyelination of the nerve at its entry to root. The aberrant loop of the artery, Management the pons. The resultant hyperactivity of most commonly the superior cerebellar, Infection should be treated with a the nerve is transferred to demyelinated is identified, gently moved from the 14-day course of antibiotics. Allergic pain fibres and causes ectopic action nerve root and kept away by use of small sinusitis usually responds to intranasal potentials in these fibres, causing pledgets of teflon felt. This procedure was corticosteroids. Occasionally, when pain paroxysmal severe pain. reported to have a 90–95% success rate, is persisent, at the patient’s insistence, but a moderate relapse rate was seen tooth extraction or costly root canal Imaging long term in follow-up studies.6 therapy is undertaken. Inevitably, this fails Magnetic resonance imaging (MRI) is In other surgical procedures, a needle to relieve the pain. Apart from the dental typically normal although there is a small is placed percutaneously via the foramen implications, these invasive procedures incidence of definable pathology (eg ovale using an image intensifier. These may enhance the pain and establish a intracranial tumours, vascular anomalies). procedures include balloon compression, chronic refractive pain pattern. Frontal Pain simulating trigeminal neuralgia radiofrequency lesioning or glycerol sinus pain is felt above the orbit. It is may occur in young adults with multiple injection partially lesioning the trigeminal a medical emergency requiring urgent sclerosis due to the presence of a ganglion. A similar goal may be achieved decompression if accompanied by peri- demyelinating plaque at the root entry by stereotactic radio-surgery using orbital oedema. of the trigeminal nerve into the pons. focused radiation to create a lesion within High-resolutions T2-CISS (constructive the nerve root. Trigeminal neuralgia interference in steady state) sequences The severe, lightning pain of trigeminal and magnetic resonance angiography Glossopharyngeal neuralgia neuralgia commonly occurs in the (MRA) on 3T MRI scanners may show The glossopharyngeal and fibres of maxillary or mandibular divisions of the the tortuous artery compressing the the vagus nerves supply sensation to trigeminal nerve. Characteristically, the trigeminal nerve at its entry to the pons. the posterior third of the tongue and pain induces a sudden wince, leading to These particular sequences may be oropharynx. Glossopharyngeal neuralgia is the descriptive term tic douloureux. Pain useful in defining surgical treatment an uncommon condition producing severe is typically felt in a small area of the face, options, but are not otherwise indicated. lancing pain in the oropharynx or base but may appear to originate from the teeth of the tongue when swallowing. Rarely, or other oral structures. However, there is Medical management the pain may be felt in the posterior often limited localisation early in the onset. Pharmacological therapy should be mandibular region. The causation and Sometimes there is a continuous dull ache initiated if history and clinical examination quality of pain are similar to those of at the trigger zone, or the patient may be strongly suggest trigeminal neuralgia. trigeminal neuralgia. Glossophayngeal asymptomatic between pain paroxysms. It is common practice to commence neuralgia should be considered if a sharp The pain may be precipitated by eating, with carbamazepine 100 mg twice daily pain occurs when swallowing. However, drinking or by jaw movements, thereby and increase the dose as required.5 pharyngeal disease or an ulcer at the base simulating acute dental pulpitis. Patients should be reviewed frequently of the tongue is a far more common cause Pain may also be triggered by talking, as drug toxicity may occur. Monitoring of this type of pain. It frequently responds air moving across the face (eg being out in serum levels is of little value. Newer to administration of carbamazepine. the wind) or light touch to the skin of the anticonvulsant agents (eg gabapentin, face, sometimes in defined areas. After pregabaline and lamotrigine) are generally Facial migraine stimulation, there may be a refractive effective, well tolerated and have low Uncommonly, migraine may present with period of approximately 60 seconds during toxicity.6 The use of infiltrative local prodromal symptoms followed by pain in which time repeated contact with the anaesthesia or a regional nerve block the peri-orbital region, which may diffuse trigger zone does not produce a response. (bupivacaine plus a corticosteroid) to the cheek and mandible. Management The condition may have a relapsing and close to the trigger zone may provide is as for typical migraine. remitting pattern, particularly early in the short-term pain relief where other drug illness. therapies fail. Postherpetic neuralgia Herpes zoster commonly affects a Aetiology Surgical treatment branch of the trigeminal nerve in the The condition is frequently caused by an The most favoured treatment is elderly and immunocompromised or aberrant loop of an artery, most commonly microvascular decompression, which immunosuppressed patients. In a recent

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study, 25% of participants who were 85 result before commencing treatment can TMJ dysfunction when aural causes are years and older had been affected by the result in permanent ocular damage due to excluded. However, dental treatment is disease.5 Post-herpetic neuralgia occurs concurrent inflammation of the ophthalmic not indicated unless the above clinical in 10% of all patients with Herpes zoster arteries. The presence of tenderness findings are present. TMD is not a infection and 75% of those over the age of and hypersensitivity over the superficial diagnosis of exclusion. 70 years. Burning, aching or, occasionally, temporal artery, together with a raised lightening pain with tenderness over erythrocyte sedimentation rate (ESR), Imaging the affected dermatome may persist for warrants immediate commencement MRI is the ‘gold standard’ as it shows many months after the vesicular lesions of oral prednisolone (commonly 50 mg the articular disc and its attachments of shingles have resolved. In established daily). The dose of prednisolone is titrated graphically. An OPG reveals joint pain, carbamazepine, amitriptyline or depending on ESR and clinical response, morphology and makes for easy gabapentin may minimise this distressing and it is frequently necessary to continue comparison of the two sides. symptom. Tramadol or a regional nerve drug therapy for more than six months. block may be effective where the pain is Management refractive. Multiple sclerosis Initially, myofascial pain and TMD This demyelinating disease may mimic should be treated conservatively by Elongated styloid process trigeminal neuralgia and cause intermittent resting the joint (restricting opening and (Eagle’s syndrome) lancing facial pain. It should always be chewing), application of heat and use This anatomical variant may result from considered, particularly in a younger adult of simple analgesia. The combination of calcification of the stylohyoid ligament.7, 8 who has other neurological deficits. MRI is paracetamol, alternating two-hourly with It produces a sharp, occasionally bilateral, usually diagnostic in this condition. a non-steroidal anti-inflammatory agent, is pain when the process impinges on the frequently effective. Diazepam, 5 mg, at soft tissues of the neck (eg swallowing, Temporomandibular joint night when muscle tenderness is present jaw, head movements). There may be dysfunction may provide relief through its skeletal neck tenderness at the tip of the process. Musculoskeletal causes of orofacial muscle relaxant and anxiolytic effects. The incidence of an elongated styloid pain are common. It is important to The patient should be referred for dental process (>2.5 cm) is 4% and many cases differentiate temporomandibular joint assessment if there is no response to are asymptomatic.7 The diagnosis can be dysfunction (TMD) from myofascial pain, conservative measures. A removable confirmed by an orthopantogram (OPG) which is more frequent. acrylic (occlusal) splint, worn at night, may radiograph or plain skull films. Although The diagnosis of TMD must be made relieve myofascial pain, inflammation10 it is an uncommon cause of pain on from positive findings, which include:9 and, in cases of bruxism, prevent wear swallowing, some patients report multiple • pain with mandibular movements, of the teeth from grinding. However, specialist and dental consultations particularly when eating. Pain in the many authorities are of the opinion that before the correct diagnosis is made. region of the temporomandibular joint these splints are of little value in most Conservative treatment may temporarily (TMJ) on awakening may be due to cases of TMD. Their empirical use when relieve symptoms, but ultrasonic teeth grinding. Clenching may also TMD is suspected should therefore be osteotomy is the treatment of choice produce pain and tenderness in the discouraged. where pain is troublesome. muscles of mastication Some investigators believe TMD may • restricted jaw movements (individuals precipitate migraine, and masticatory Cranial (temporal) arteritis normally have a pain-free opening of muscle hyperactivity often occurs in This inflammatory disease (giant cell 35–45 mm) a migraine attack.11 Some dentists, arteritis) affects the media of medium- • tenderness over the joint therefore, insert an occlusal splint, arguing sized cranial arteries. It may present as • crepitus or clicking during mandibular it may relieve the headache and rest the claudication when chewing, together with movements muscles of mastication. Although this a constant unilateral headache and diffuse In myofascial pain syndrome, there is may occur, splints rarely prevent headache pain around the ear. Pain experienced frequently pain and tenderness over the recurrence. while eating results from involvement masticatory muscles. A trigger point of the media in the masseteric artery. A and muscle fatigue on chewing may be Joint arthrocentesis temporal artery biopsy should be obtained, present. This safe, outpatient procedure is effective but histopathology often fails to identify a Patients presenting with pain around in many cases of TMD where there are no lesion in the presence of disease as ‘skip’ the ear are sometimes referred to a major morphological changes. The joint is lesions may occur. Waiting for a positive dentist, with a provisional diagnosis of lavaged and a steroid solution inserted.

Dilatation of the joint space and removal excess of the duration of the anaesthetic. 9. Fonseca RJ, Marciani RD, Turvey TA, editors. of the fine elements of joint destruction, If no improvement is gained, the pain is Oral and maxillofacial surgery. 2nd edn. Missouri: Elsevier, 2009, p. 815. together with the severing of adhesions, likely to be central in origin. 10. Al-Anim Z, Davies SJ. Stabilisation splint therapy provides symptomatic relief in more than In a recent study, administering an for temporo-mandibular joint dysfunction. Cochrane Database Sys Rev 2004;CD002778. 70% of cases where there is no major occipital nerve block produced pain relief in 11. Hupp JR, Ellis E, Tucker MR. Contemporary oral structural change. However, the duration all patients with occipital neuralgia and in and maxillofacial Surgery. 6th edn. Missouri: of pain relief is variable.12 75% of cases of trigeminal neuralgia. The Elsevier, 2014. 12. Machon V, Sedý J, Klíma K, Hirjak D, Foltán R. mean duration of relief was 27 days. This is Arthroscopic lysis and lavage in patients with Temporomandibular joint surgery a particularly useful and safe technique in temporo-mandibular anterior disc displacement Open joint surgery is reserved for without reduction. Int J Oral Maxillofac Surg elderly patients with occipital neuralgia in 2012;41:109–13. patients who do not respond to the above whom poly-pharmacy increases the risks of 13. Sidebottom AJ. Current thinking in management, or those with marked joint adverse drug interactions.14 temporomandibular joint management. Br J Oral Maxillofac Surg 2009:47:91–94. derangement. Patients are increasingly 14. Jurgens TP, Muller P, Seedorf H. Occipital nerve being managed with pain control and Conclusion block is effective in craniofacial neuralgia but not other non-surgical options. Even when in idiopathic persistent facial pain. J Headache Facial pain is a common presentation Pain 2013;13:199–213. there is restricted, painful jaw opening, in clinical practice. The great majority of the preferred treatment is arthroscopy and cases are due to diseases of the oral arthrocentesis.13 cavity, but the remainder often prove to be Psychological component a diagnostic challenge. However, almost all of facial pain cases can be diagnosed correctly and the pain controlled with a systematic approach A mental health and social history is using investigations judiciously. essential when assessing facial pain, as depression and anxiety may increase Author pain severity and make its management Geoffrey Quail OAM, MBBS, MMed, MDSc, PhD, DDS, FRCP, FRACDS, FRACGP, FACTM, more difficult. Conversely, persistent facial DTM&H, Associate Professor, Monash University pain may amplify a neurosis or psychosis. Department of Surgery, Monash Medical Centre, Clayton, VIC. [email protected] Depression and anxiety are more common Competing interests: None. in elderly women living alone, although Provenance and peer review: Not commissioned, it is seen at all ages. In addition, there externally peer reviewed. is a small number of patients in whom Acknowledgement a diagnosis cannot be made. Low-dose The author would like to thank Frank Vajda AM, tricyclic antidepressants taken before MBBS, MD, FRACP, FRCP, Department of retiring, together with a supportive Neurology, Royal Melbourne Hospital, Parkville, for environment, often lead to significant pain his help with preparation the manuscript. reduction in these patients. References 1. Stovner LJ, Hagen K, Jensen R, et al. The Regional nerve blocks in global burden of headache: A documentation of diagnosis and management headache prevalence and disability worldwide. Cephalgia 2007;27:193–210. In undiagnosed facial pain, nerve block 2. Quail G. Atypical facial pain. Aust Fam Physician may relieve the pain and aid in determining 2005;34:641–45. 3. Quail G. The painful mouth. Aust Fam Physician the site from which it originates. The 2008;32:935–38. source is likely to be local if an injection of 4. Davies DV. Gray’s anatomy. 34th edn. London: a short-acting local anaesthetic (lignocaine) Longmans, 1967, p. 1155. 5. Expert Group for Neurology. Neurology: close to the pain site provides temporary Trigeminal neuralgia. In: eTG complete. relief. A long-acting agent, including Melbourne: Therapeutic Guidelines Ltd, 2013. bupivacaine with adrenaline, should then 6. Longo DL, Fauci DL, Kasper JL, et al. Harrison’s principles of internal medicine. 18th edn. New be administered. This will provided time York, 2012. p. 3361. for the inflamed nerve to recover from 7. Eagle WW. Elongated styloid process. Report of repeated stimulation at the peripheral two cases. Arch Otolaryngol 1937;25:584–87. 8. Har-El G, Weisbord A, Sidi J. Ossified segments nerve endings. Adding a steroid to the of the stylohyoid ligament. A case of radiological anaesthetic solution may provide relief in misdiagnosis J Laryngol Otol 1987;101:516–18.