Neurological Aspects of Arachnoiditis


IMPORTANT NOTE:

The information in this article is for general purposes only and is NOT a substitute for medical consultation. You should NEVER attempt to self-diagnose.

 

DIZZINESS:

In my 1999 survey(*) 44% of respondents had dizziness/vertigo.

So it is quite a common problem.

Dizziness is a rather vague term which can encompass a range of sensations, but usually refers to:

  • Lightheadedness
  • Feeling faint
  • Feeling a loss of balance
  • Feeling unsteady
  • Giddiness

Vertigo, on the other hand, refers to a sensation of spinning or falling. Sitting up or moving around may make it worse, and it may be bad enough to cause sickness. 

Motion sickness is nausea and lightheadedness when moving (usually in a vehicle); it includes sea sickness.

Common causes of dizziness/vertigo or unsteadiness related to arachnoiditis include:

  • Medication: including salicylates (aspirin); caffeine; alcohol; anti-seizure drugs (given for pain) sedatives etc.
  • Multiple sensory deficits: nerve damage in arms and legs in arachnoiditis may cause a loss of balance
  • Weakness in legs may cause loss of balance
  • Migraine: especially vestibular
  • Benign paroxysmal positional vertigo (BPPV)
  • Labyrinthitis (usually viral)
  • Meniere’s disease
  • Low blood pressure, abnormal heart rhythm: may cause faintness: a drop in blood pressure on standing (orthostatic hypotension) is a relatively common problem (contributed to by autonomic neuropathy
  • Autonomic neuropathy : e.g. in diabetes
  • Metabolic disturbance: including low glucose, hypothyroidism
  • Allergy
  • (Severe anaemia)

NOTE: If you have developed sudden weakness or tingling/numbness down one side of your body, in association with dizziness, you should seek immediate medical attention to exclude a stroke.

Tests:

  • Positional test: simple test during clinical examination; manoeuvre to trigger vertigo from a change from sitting to lying down rapidly with head turned to one side and then other. This may trigger transient dizziness (lasting a minute or so) and should not make your dizziness worse after that. The eyes must be kept open for your doctor to check for nystagmus (flickering of the eyes) which will tell the doctor what kind of dizziness you have.
  • ECG: to check heart rhythm; possibly echocardiogram and exercise tests
  • Blood tests: electrolytes, blood count, ESR (detects inflammation) glucose metabolism
  • MRI scan
  • Hearing tests
  • Balance tests : ENG (electronystagmography)
  • Caloric testing
  • Angiography (note: not every patient will need every test)

Methods of reducing dizziness:

  • Avoid rapid changes of position, especially from lying down to standing up or turning around.
  • Avoid extremes of head movement, especially looking up, or turning
  • Eliminate products which impair circulation: caffeine, nicotine, salt.
  • Minimise exposure to precipitating factors
  • Avoid hazardous activities when you are dizzy (including driving)
  • Don’t become totally immobile; moving around may help you to develop central compensation which will reduce the problems.

Travel sickness:

  • Always ride where your eyes will see the same motion your body and inner ears feel.
  • Don’t read while travelling
  • Don’t sit in a seat facing backward
  • Avoid strong odours and spicy/greasy foods

Treatment:

The goal is to treat the underlying problem(s). If that is not feasible, then reducing the symptoms should be the prime target. Drugs such as promethazine (Phenergan) or Cyclizine may be helpful in reducing symptoms such as nausea.

BPPV can be managed quite successfully by techniques such as CRP, (canalith repositioning procedure), in which the patient’s head is moved through a series of positions which move the crystals through the inner ear into a position in which they no longer cause symptoms. The technique is quick (takes minutes) and highly successful, although it may need repeating occasionally. Self-guided positional exercises (e.g. Brandt-Daroff exercises) may be undertaken by the patient if BPPV recurs. They involve sitting on a bed with the head turned 45 degrees to one side, then quickly lying down to the opposite side with the head still turned so that the area behind the ear touches the bed. This position and all subsequent ones need to be maintained for 30 seconds: 5 more should be repeated. At least 3 sessions a day should be completed. The eyes may be kept closed to reduce vertigo.

For Meniere’s disease, diuretics and salt reduction may be prescribed. Patients with mild infrequent attacks tend to prefer not to take maintenance treatments such as prochlorperazine and cinnarizine which may have unpleasant side effects. (Meniere’s Disease Society 1999)

For orthostatic hypotension, salt or fludrocortisone may be indicated.

Surgery is rarely indicated. Ablative treatment given locally into the inner ear may reduce vertigo in some patients. Endolymphatic sac surgery and vestibular nerve section/neurectomy are not destructive to hearing, whereas labyrinthectomy does affect hearing.

Vestibular rehabilitation may be needed if dizziness persists for weeks or months: this balance training is taught by trained health professionals. It aims to correct the imbalance between the functioning of the right and left vestibular organs in the inner ear; this is achieved by processes called ‘vestibular compensation’, and this is possible even with permanent damage to the inner ear. In much the same way as astronauts are taught to compensate for loss of gravity and positional sense in space, patients can be taught to re-programme their brain to counteract the abnormal signals it receives. Vestibular exercises involving movements of the eyes, head, trunk and finally the whole body under different visual circumstances (e.g. with eyes open or closed) can help develop vestibular compensation. It is important to note that in order to achieve this, the brain must be aware of imbalance or dizziness; this means that anti-vertigo medication may need to be stopped. Dizziness experienced during the exercises should not be regarded as a ‘stop’ sign, but as an inherent part of the process of compensation. However, extremes of dizziness which render you sick or exhausted are not to be induced. These exercises are also known as Cawthorne Cooksey or balance exercises. 

EYE PROBLEMS

In the 1999 survey, 45% of respondents said they had some sort of visual problems. Further investigation revealed that common problems included:

  • Photoaversion: intolerance of bright light: a very common problem, most often after myelograms or epidural injections; it may be due to hypersensitivity of the nervous system. Specific ocular (eye) causes include: conjunctivitis, uveitis, dry eye;
  • Dry eyes: A gritty feeling or just sore eyes seems to be a common problem with arachnoiditis. In a few people, a condition called Sjogren’s syndrome may be diagnosed: this involves dry eyes and mouth and joint pains. Dry eye syndrome is usually due to reduced aqueous tear production (keratoconjunctivitis sicca), reduced quality of the tear film, disorder of the corneal surface or a lid dysfunction. Other disorders that can cause dry eyes include rheumatoid arthritis and SLE, connective tissue disorders (sarcoidosis, amyloidosis) and Stevens-Johnson syndrome. Drugs that may cause reduced tear flow include: diuretics, antihistamines, tricyclic antidepressants (e.g. amitriptyline), oral contraceptive pill, atropine derivatives, and beta-blockers (this list is not comprehensive). Symptoms include transient blurred vision and aversion to bright lights. Schirmer’s test may be performed to assess the possibility of Sjogren’s syndrome. Artificial tear solutions such as Hypromellose 0.3% can be used at up to 30 minute intervals if severe (a preservative–free preparation is best); at night, simple ointment (or Lacrilube/Lubritears) provides more sustained lubrication. Topical steroids should be avoided. (Acetylcysteine eye drops can be useful if there is a problem with sticky, viscous mucous in the eye). 
  • Blurred vision: this is probably most commonly a result of medication such as morphine and related drugs. Other causes require full ophthalmic assessment. Anticholinergic drugs such as the antidepressant amitriptyline, may affect the ability to focus, as may morphine and related drugs.
  • Pain around the eye: these can be sharp, lightning pains, which can feel as if they go right through the eye. They can be related to neuralgia (see below)
  • Eye symptoms in migraine: these may include seeing an ‘aura’ before onset of the headache.
  • Conjunctivitis: infective inflammation of the conjunctiva; chronic illness may generally debilitate and therefore predispose to infection.

Less commonly:

  • Uveitis: inflammation of the eye: if the front of the eye is involved, the eye will be red, and there will be light sensitivity, and some reduction in vision; often it occurs in one eye and there is rapid onset of symptoms; if the back of the eye is affected, these symptoms may not occur, except for reduced vision which can range from mild to severe; both eyes may be affected.
  • Floaters: these are tiny clumps of cells in the fluid behind the pupil (vitreous humour) at the back of the eye, which appear, however, to ‘float’ in front of the eye. They cast shadows on the retina, the nerve layer at the back of the eye. Floaters may appear as a variety of shapes including dots, lines, cobwebs, circles, clouds. Generally, they are harmless, but can be a nuisance if they interfere with activities such as reading. Occasionally, new floaters can arise due to posterior vitreous detachment which is when the vitreous gel shrinks away from the retina. This is more common in older middle-aged people who are nearsighted, have undergone cataract surgery, have had previous laser treatment, have had inflammation in the eye or have had head trauma.  Most people learn to live with their floaters. Some specialists recommend laser treatment, whereas others suggest that this is likely only to ‘rearrange’ the floaters. The other surgical option, vitrectomy, carries risks of accelerated cataract formation, infection and retinal detachment.
  • Horner’s syndrome: often an acute condition which can occur after epidural injection: all the symptoms are on one side of the face. They comprise: drooping eyelid, skin feels warm and dry (no sweating) and pupil constricted. Horner’s may also occur if spinal nerve roots in the neck are damaged.
  • Raeder’s syndrome: a combination of pain, drooping eyelid and constricted pupil; there may be a preceding history of episodic pain in or around the eye and cluster headaches. This is a benign condition that may arise during a cluster of headaches and resolving spontaneously once the headaches have ceased.
  • Adie’s Pupil: a ‘tonic’ (poorly responsive) dilated pupil, which may be associated with a generalised dysautonomia, that is, abnormal autonomic functioning (involuntary nervous system regulating blood pressure, sweating, gut function, sphincter tone etc. : see below) which is occasionally seen in patients with arachnoiditis.
  • Thyroid eye disease: some arachnoiditis patients who have a history of a myelogram (oil or water-based contrast agent) may develop thyroid disorders. This could be related to the iodine content of the myelogram dye. Hyperthyroid disease may present with eye problems: this is termed Grave’s disease. Common symptoms include: eyelid retraction, irritation in the eye, watery eyes(or dry eyes if the eyelid retracts considerably), redness, double vision, pain and reduction in vision. The eyes may appear to ‘bulge’ because the fat and muscles around the eye may be infiltrated with antibodies; this may put pressure on the optic nerve, and cause problems with vision. There may be difficulty in moving the gaze around, because the muscles around the eye are not working properly. The most important aspect of treatment is to normalise the thyroid hormone levels. Steroids (given orally) may also be needed to reduce the pressure on the optic nerve. Dry eyes can be treated with topical lubricants.

ITCHING (PRURITUS)

Itching is defined as an unpleasant sensation which elicits the desire to scratch. It can be extremely distressing and debilitating.

CAUSES:

A.      External causes

B.       Skin diseases

C.       Systemic causes

Localised:

  • Scalp: seborrhoeic eczema, neurodermatitis, psoriasis; head lice
  • Eyelid: airborne irritants or allergens; allergic reactions to cosmetics/nail varnish
  • Fingers: eczema, scabies, contact dermatitis
  • Legs: gravitational and discoid eczema
  • Anus (pruritus ani): anal fissure, haemorrhoids
  • Vulva: candidal infection (especially after antibiotics or in diabetic patients)

Generalised:

External causes:

  • Climatic: low humidity (e.g. cold weather or central heating) renders skin brittle and allows minor irritants such as soap to penetrate, causing mild irritation. Dry skin in elderly causes common itchiness. Dry skin associated with atopic eczema also prone to itching. High humidity may also cause itching secondary to sweat retention.
  • Particulate matter: foreign body e.g. glass fibre, hair, etc.
  • Chemical : detergents (optical brighteners)
  • Parasite infestation : scabies, mites
  • Aquagenic pruritus: on contact with water: due to underlying systemic disease
  • Excessive bathing
  • Radiotherapy   

Skin diseases:

  • Urticaria
  • Lichen planus
  • Contact dermatitis
  • Atopic eczema
  • Insect bites
  • Psoriasis
  • Fungal infection
  • Dry skin
  • Sunburn
  • Pemphigoid

Systemic causes:

B = Blood disease including iron deficiency

L = Liver disease including drug-induced liver damage

I = Immunological, Autoimmune,Infection

N = Neurological disease, Neoplastic disease(cancer)

K =Kidney disease: including chronic renal failure

E = Endocrine disease: diabetes*; thyroid disease  (*usually localised itching due to candidiasis)


In dealing with arachnoiditis, we are likely to be looking mostly at N, D (and possibly I).

Neurological  causes include MS. Paroxysmal unilateral (one sided) pruritus has been recorded with central nervous system disease.

Neurogenic pruritus: may occur after strokes or with spinal tumours or MS. Hence it is feasible to suggest that itching might be a feature of arachnoiditis.

Bearing in mind the possible link between arachnoiditis and autoimmune diseases, it is important to bear in mind that itching can be a feature in conditions such as Systemic Lupus Erythematosus, and Sicca syndrome (Sjogren’s).

Drug-induced itching: commonly seen with:

  • Opiates
  • CNS stimulants/depressants
  • Allergies: sensitivity to a variety of drugs seems to occur in some arachnoiditis patients
  • Cimetidine
  • aspirin
  • monoclonal antibodies
  • vitamin B complex
  • erythromycin
  • oestrogen, progesterone, testosterone
  • tolbutamide
  • phenothiazines
  • chemotherapy
  • quinidine   (note: this is not an exhaustive list)

Treatment:

  1.  treatment of the underlying cause if possible
  2. general symptomatic treatment: reduce/avoid precipitating factors: e.g. dryness of environment, wearing irritating fabric, overheating, hot, spicy food, stress.  Also: application of topical treatment such as emollient, antihistamine cream or calamine lotion.
  3. Oral medication: antihistamine tablets (histamine is a known itch mediator); tricyclic antidepressants (such as amitriptyline) may help, and are useful in combating the neuropathic pain commonly experienced by arachnoiditis patients.
  4. Other measures include: TENS and Odansetron.