Monday, 1 October 2012

Facial Pain

A 64 year old woman presented with a history of "2 years (yes years) of heaviness in her chest (worse over the past 2 weeks), 2 weeks of nausea, intermittent subjective "numbness and tingling" in both hands and feet, and "severe pressure" behind her left ear which felt like someone was "sticking a knitting needle" into her ear. The ear pain radiated into the left side of her jaw. There was no hearing deficit and no tinnitus. There was a background of dysthymia and fatigue. She had seen an ENT specialist who was not able to provide an explanation or any treatment for her pain and she was distressed that he had "taken her money and didn't want to see her again. She had previously been diagnosed as having eustachian tube dysfunction but did not find this diagnosis very satisfactory. Overall she seemed dysthymic with a flavour of "learned helplessness". A bit of a "heart sink" presentation but doesn't mean that she shouldn't have a comprehensive and rational assessment of her presenting complaint (s)

There were no recent bloods to identify cardiac risk factors such as cholesterol or diabetes.
BP was 160/90.
ECG was "normal"
Troponin was negative and other bloods were noncontributory. Auto-immune serology is still pending.
The patients usual GP had arranged an MRI for the following week of her neck and I added a request for brain and left ear imaging/ report.

I can't recall medications etc but here are the questions I particularly wanted to look up:

  1. What are the causes of unilateral facial/ ear pain?
  2. What is somatisation and what are other similar syndromes?
  3. What are the diagnostic criteria of chronic fatigue?
I have taken most of the information below from Up To Date

What are the causes of unilateral facial pain?

"The causes are myriad, and misdiagnosis and mismanagement are common." Up To Date

CENTRAL CAUSES OF FACIAL PAIN

            Anasthesia dolorosa

Persistent, painful anaesthesia in the distribution of the trigeminal or occipital nerve. The patient has sensory loss (decreased sensation to pin-prick testing) but can feel pain. This may be a complication of thermocoagulation used to treat trigeminal neuralgia.

            Central Post Stroke Pain

Pain and altered sensation in any area of the face following a stroke.

            Facial pain cased by Multiple Sclerosis

Can occur unilaterlly or bilaterally

            Persistent idiopathic facial pain

This basically means the patient has facial pain but no one can find a cause.

            Burning Mouth Syndrome

Sensation of burning mouth for which no medical or dental cause can be found. There are a number of Internet sites for patients who have this syndrome. Generally there is a lot of associated distress and fear of not being taken seriously.

NEURALGIAS

Pain is usually severe at onset and is described as lancinating, "electric shocks," or as "jabbing." The pain can last a fraction of a second, or for several seconds. Some neuralgic conditions have trigger zones--areas that when stimulated provoke an attack.

            Glosso-pharyngeal neuralgia

Neuralgic-type pain in the region of the glossopharyngeal nerve (CN IX and X)

Glossopharyngeal nerve (IX)

Causes spasms of severe, stabbing pain of the ear, tonsillar fossa, base of the tongue, or beneath the angle of the jaw. Triggers include chewing, swallowing, coughing, speaking and yawning.
The pain spreads upward from the oropharynx toward the ear. The severe spasms last for seconds to minutes, but there may also be a mild constant background pain. The spasms may awaken the patients from sleep.

There are "idiopathic" and "secondary" forms of glossopharyngeal neuralgia. Secondary causes include demyelinating lesions, cerebellopontine angle tumor, peritonsillar abscess and carotid aneurysm.

The evaluation of a patient suspected of suffering from glossopharyngeal neuralgia includes a careful history, especially enquiring about the presence of trigger factors and nocturnal awakening.

MRA are indicated in virtually all patients to rule out a mass lesion or vascular pathology.

            Nervus intermedius neuralgia

A rare disorder characterized by brief paroxysms of pain felt deeply in the auditory canal. Also called geniculate neuralgia or Hunt neuralgia.

Nervus intermedius anatomy
 

This is a very RARE disorder.
The International Classification of Headache Disorders requires that all three of the following are present:
  • Pain (otalgia) not due to another cause such as glossopharyngeal neuralgia.
  • Pain paroxysms of intermittent occurrence, lasting for seconds or minutes, in the depth of the ear
  • Presence of a trigger area in the posterior wall of the auditory canal
            Occipital neuralgia


Occipital nerve from Brown: Atlas of Regional Anesthesia, 3rd ed., Copyright © 2006 Saunders
 
Cutaneous fields of the head and neck (from Up To Date)

The cause is unknown but may result from occipital nerves getting squashed a bit by neck and scalp muscles.

Occipital neuralgia causes jabs of electric-shock like pain in the back of the head (usually on one side). the pain starts in the back of the neck (around C3) and spreads to the front of the head. There may be sensitivity/ tenderness over the branches of the nerve.

Occipital neuralgia
Pain starts in the neck and spreads forwards

Other causes of occipital neck pain include:
  • Muscular problems (trapezius or sternocleidomastoid)
  • C2 and C3 disc pathology (eg cervical discogenic pain from degeneration)
  • C2 and C3 facet joint problems (often chronic following "whip-lash" like injury)
  • Vertebral artery problems

An occipital nerve block is almost diagnostic. If the pain doesn't go away then there is most likely another diagnosis for the pain.

            Postherpetic neuralgia

Neuropathic pain following an episode of herpes zoster (shingles).

            Trigeminal Neuralgia (Tic douloureux)

A VERY COMMON cause of facial pain characterised by spasms of electric-shock like pain in the trigeminal distribution (V1 or V2 or V3). It is more common in women and is probably caused by the trigeminal nerve getting squashed by an artery. The nerve may also be compressed by an acoustic neuroma (or other tumor) or by an epidermoid cyst.

Secondary causes (such as tumor) are unlikely but may be present even if the neurological examination is normal (one studied found this to be the case 15% of the time).

Carbemazepine is the standard treatment

Baclofen may be useful. the starting dose is 5mg TDS with gradual titration to 50mg a day.
Sedation, dizziness, and dyspepsia can occur with treatment, and the drug should be discontinued slowly.
 
Adjunct therapy with lamotrigine (400 mg daily) may be helpful.
 
Surgical therapy is a possibility in refractory cases.
 

Other casues of unilateral facial pain

  • Temporal arteritis (50% have claudication; pain may be in the temporal or occipital region; visual loss is a feared complication)
  • Dental pain
  • Cancer pain
 

What is somatisation?

The DSMV-IV-TR and ICD 10 both discuss somatisation/ somatiform disorder.
Essentially the patient presents with one or more medically unexplainable symptoms. The symptoms usually lead to significant impairment in functioning. Patients are often preoccupied with their symptoms. It is very common in women, especially those who are poorly educated and marginalised. There is often a history of childhood sexual abuse or violence.

What are the diagnostic criteria of chronic fatigue?

Everyone seems to present differently but there are some commonalities:

  • Onset of fatigue is sudden and may follow a mild infection (such as "the flu" or EBV)
  • Following the infection the patient is overwhelmingly fatigued and suffers from disordered sleep and cognition ("cotton wool brain")
  • Physical activity makes things worse
  • Usually these patients have been very high functioning and not the "heart sink" malingering type with chronic back pain etc. Having said this, there may be a history of psychiatric problems in the past.
CFS is defined by the CDC as unexplained, persistent or relapsing fatigue that is of new or definite onset; is not the result of ongoing exertion; is not alleviated by rest; and results in substantial reduction in previous levels of occupational, educational, social, or personal activities
and
Four or more of the following symptoms that persist or recur during six or more consecutive months of illness and that do not predate the fatigue:
  • Self-reported impairment in short term memory or concentration
  • Sore throat
  • Tender cervical or axillary nodes
  • Muscle pain
  • Multijoint pain without redness or swelling
  • Headaches of a new pattern or severity
  • Unrefreshing sleep
  • Post-exertional malaise lasting ≥24 hours