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This is most commonly achieved through the use of fresnel prisms. These slim flexible plastic prisms can be attached to the patient's glasses, or to plano glasses if the patient has no refractive error, and serve to compensate for the inward misalignment of the affected eye. Unfortunately, the prism only correct for a fixed degree of misalignment and, because the affected individual's degree of misalignment will vary depending upon their direction of gaze, they may still experience diplopia when looking to the affected side. The prisms are available in different strengths and the most appropriate one can be selected for each patient. However, in patients with large deviations, the thickness of the prism required may reduce vision so much that binocularity is not achievable. In such cases it may be more appropriate simply to occlude one eye temporarily. Occlusion would never be used in infants though both because of the risk of inducing stimulus deprivation amblyopia and because they do not experience diplopia.
Other management options at this initial stage include the use of botulinum toxin, which is injected into the ipsilateral medial rectus (botulinum toxin therapy of strabismus). The use of BT serves a number of purposes. Firstly, it helps to prevent the contracture of the medial rectus which might result from its acting unopposed for a long period. Secondly, by reducing the size of the deviation temporarily it might allow prismatic correction to be used where this was not previously possible, and, thirdly, by removing the pull of the medial rectus it may serve to reveal whether the palsy is partial or complete by allowing any residual movement capability of the lateral rectus to operate. Thus, the toxin works both therapeutically, by helping to reduce symptoms and enhancing the prospects for fuller ocular movements post-operatively, and diagnostically, by helping to determine the type of operation most appropriate for each patient.
The first aims of management should be to identify and treat the cause of the condition, where this is possible, and to relieve the patient's symptoms, where present. In children, who rarely appreciate diplopia, the aim will be to maintain binocular vision and, thus, promote proper visual development.
Thereafter, a period of observation of around 9 to 12 months is appropriate before any further intervention, as some palsies will recover without the need for surgery.
Congenital fourth cranial nerve palsy can be treated with strabismus surgery, where muscle attachment sites on the globe are modified to realign the eyes. Some eye doctors prefer conservative or no management of congenital fourth nerve palsy.
Other eye doctors recommend surgery early in a patient's life to prevent the compensatory torticollis and facial asymmetry that develop with age.
Prism lenses set to make minor optical changes in the vertical alignment may be prescribed instead of or after surgery to fine-tune the correction. Prism lenses do not address torsional misalignment and this may limit their use in certain cases. An additional consideration of prism lenses is that they must be worn at all times. Prism lenses reduce vertical fusional demands by allowing the eyes to rest in their vertically misaligned state. When they are removed the patient may experience vertical diplopia they find hard to resolve due to the rested state of their eyes.
Cases of congenital fourth nerve palsy vary in magnitude and way they affect the motion of the superior oblique muscle. Therefore different surgeries are available dependent upon the type of misalignment. Sometimes surgery on more than one eye muscle is required. In some simpler, unilateral cases a single surgery may suffice. In these cases the main problem is that the inferior oblique muscle of the same eye acts unopposed by the weakened superior oblique muscle, pulling the eye up. An example of a safe and effective procedure is a disinsertion of the inferior oblique muscle to allow it to reattach itself further down the globe of the eye. This acts to 'weaken' its action and allow the eye to move back into a more neutral alignment.
In all cases of congenital fourth nerve palsy, it is important to see an experienced strabismologist about management/treatment options. A strabismologist is an ophthalmologist (eye doctor) specialising in eye movement disorders.
There is no treatment of conjugate gaze palsy itself, so the disease or condition causing the gaze palsy must be treated, likely by surgery. As stated in the causes section, the gaze palsy may be due to a lesion caused by stroke or a condition. Some of the conditions such as Progressive supra nuclear palsy are not curable, and treatment only includes therapy to regain some tasks, not including gaze control. Other conditions such as Niemann-Pick disease type C have limited drug therapeutic options. Stroke victims with conjugate gaze palsies may be treated with intravenous therapy if the patent presents early enough, or with a surgical procedure for other cases.
Initially, the condition is treated with physical therapies, such as stretching to release tightness, strengthening exercises to improve muscular balance, and handling to stimulate symmetry. A TOT collar is sometimes applied. Early initiation of treatment is very important for full recovery and to decrease chance of relapse.
In many cases recovery happens spontaneously and no treatment is needed. This spontaneous recovery can occur because distance between the injury location and the deltoid muscle is small. Spontaneous recovery may take as long as 12 months.
In order to combat pain and inflammation of nerves, medication may be prescribed.
Surgery is an option, but it has mixed results within the literature and is usually avoided because only about half of people who undergo surgery see any positive results from it. Some suggest that surgical exploration should be considered if no recovery occurs after 3 to 6 months. Some surgical options include nerve grafting, neurolysis, or nerve reconstruction. Surgery results are typically better for younger patients (under 25) and for nerve grafts less than six centimeters.
For some, recovery does not occur and surgery is not possible. In these cases, most patients’ surrounding muscles can compensate, allowing them to gain a satisfactory range of motion back. Physical therapy or Occupational therapy will help retrain and gain muscle tone back.
Practical surgical procedures used for treating synkinesis are neurolysis and selective myectomy. Neurolysis has been shown to be effective in relieving synkinesis but only temporarily and unfortunately symptoms return much worse than originally. Selective myectomy, in which a synkinetic muscle is selectively resected, is a much more effective technique that can provide permanent relief and results in a low recurrence rate; unfortunately, it also has many post-operative complications that can accompany including edema, hematoma, and ecchymosis. Therefore, surgical procedures are very minimally used by doctors and are used only as last-resort options for patients who do not respond well to non-invasive treatments.
Botox (botulinum toxin) is a new and versatile tool for the treatment of synkinesis. Initially used for reducing hyperkinesis after facial palsy, Botox was later attempted on patients with post-facial palsy synkinesis to reduce unwanted movements. The effects of Botox have shown to be remarkable, with synkinetic symptoms disappearing within 2 or 3 days. The most common treatment targets are the orbicularis oculi, depressor anguli oris (DAO), mentalis, platysma and the contralateral depressor labii inferioris muscles. Due to the short span of Botox effects though, patients must come back to the doctor for re-injection approximately every 3 months. More notable is that in a majority of patients, various synkinetic movements completely disappeared after 2-3 sessions of trimonthly Botox injections.
A more specific synkinesis, crocodile tears syndrome (hyperlacrimation upon eating), has been shown to respond exceedingly well to Botox injection. Botox is injected directly into the lacrimal gland and has shown to reduce hyperlacrimation within 24–48 hours. The procedure was shown to be simple and safe with very little chance of side-effects (although on rare occasions ptosis can occur due to botulinum toxin diffusion). Furthermore, reduction in hyper-lacrimation was shown to last longer than the expected 3 months (about 12 months).
Since Botox can mimic facial paralysis, an optimized dose has been determined that reduces involuntary synkinesis of the muscle while not affecting muscle tone.
Corticosteroids such as prednisone improve recovery at 6 months and are thus recommended. Early treatment (within 3 days after the onset) is necessary for benefit with a 14% greater probability of recovery.
Physiotherapy can be beneficial to some individuals with Bell’s palsy as it helps to maintain muscle tone of the affected facial muscles and stimulate the facial nerve. It is important that muscle re-education exercises and soft tissue techniques be implemented prior to recovery in order to help prevent permanent contractures of the paralyzed facial muscles. To reduce pain, heat can be applied to the affected side of the face. There is no high quality evidence to support the role of electrical stimulation for Bell's palsy.
The majority of patients remain symptom free and able to maintain binocularity with only a slight face turn. Amblyopia is uncommon and, where present, rarely dense. This can be treated with occlusion, and any refractive error can also be corrected.
Duane syndrome cannot be cured, as the "missing" cranial nerve cannot be replaced, and traditionally there has been no expectation that surgery will result in any increase in the range of eye movement. Surgical intervention, therefore, has only been recommended where the patient is unable to maintain binocularity, where they are experiencing symptoms, or where they are forced to adopt a cosmetically unsightly or uncomfortable head posture in order to maintain binocularity. The aims of surgery are to place the eye in a more central position and, thus, place the field of binocularity more centrally also, and to overcome or reduce the need for the adoption of an abnormal head posture. Occasionally, surgery is not needed during childhood, but becomes appropriate later in life, as head position changes (presumably due to progressive muscle contracture).
Surgical approaches include:
- Medial rectus recession in the involved eye or both eyes. By weakening the medial rectus muscles this procedure improves the crossed-eye appearance but does not improve outward eye movements (abductions).
- Morad et al. showed improved abduction after modest unilateral medial rectus recession and lateral rectus resection in a subgroup of patients with mild eye retraction and good adduction before surgery.
- Lateral transposition of the vertical muscles described by Rosenbaum has been shown to improve range of movement of the eye. The surgical procedure produces 40-65 degrees of binocular field. Orbital wall fixation of the lateral rectus muscle (muscle is disinserted and reattached to lateral orbital wall) is recommended an effective method to inactivate a lateral rectus muscle in cases of marked anomalous innervation and severe cocontraction.
Surgical release involves the two heads of the sternocleidomastoid muscle being dissected free. This surgery can be minimally invasive and done laparoscopically. Usually surgery is performed on those who are over 12 months old. The surgery is for those who do not respond to physical therapy or botulinum toxin injection or have a very fibrotic sternocleidomastoid muscle. After surgery the child will be required to wear a soft neck collar (also called as Callot's cast). There will be an intense physiotherapy program for 3–4 months as well as strengthening exercises for the neck muscles.
Other treatments include:
- Rest and analgesics for acute cases
- Diazepam or other muscle relaxants
- Botulinum toxin
- Encouraging active movements for children 6–8 months of age
- Ultrasound diathermy
It is essential that a child with strabismus is presented to the ophthalmologist as early as possible for diagnosis and treatment in order to allow best possible monocular and binocular vision to develop. Initially, the patient will have a full eye examination to identify any associated pathology, and any glasses required to optimise acuity will be prescribed – although infantile esotropia is not typically associated with refractive error. Studies have found that approximately 15% of infantile esotropia patients have accommodative esotropia. For these patients, antiaccommodative therapy (with spectacles) is indicated before any surgery as antiaccommodative therapy fully corrects their esotropia in many cases and significantly decreases their deviation angle in others.
Amblyopia will be treated via occlusion treatment (using patching or atropine drops) of the non-squinting eye with the aim of achieving full alternation of fixation. Management thereafter will be surgical. As alternative to surgery, also botulinum toxin therapy has been used in children with infantile esotropia. Furthermore, as accompaniment to ophtalmologic treatment, craniosacral therapy may be performed in order to relieve tension ("see also:" Management of strabismus).
The eye findings of Parinaud's Syndrome generally improve slowly over months, especially with resolution of the causative factor; continued resolution after the first 3–6 months of onset is uncommon. However, rapid resolution after normalization of intracranial pressure following placement of a ventriculoperitoneal shunt has been reported.
Treatment is primarily directed towards etiology of the dorsal midbrain syndrome. A thorough workup, including neuroimaging is essential to rule out anatomic lesions or other causes of this syndrome. Visually significant upgaze palsy can be relieved with bilateral inferior rectus recessions. Retraction nystagmus and convergence movement are usually improved with this procedure as well.
Mild cases of hemifacial spasm may be managed with sedation or carbamazepine (an anticonvulsant drug). Microsurgical decompression and botulinum toxin injections are the current main treatments used for hemifacial spasm.
According to a Cochrane review of 2012, controversies remain regarding type of surgery, non-surgical intervention and age of intervention.
The aims of treatment are as follows:
The elimination of any amblyopia
A cosmetically acceptable ocular alignment
long term stability of eye position
binocular cooperation.
The prognosis of a lesion in the visual neural pathways that causes a conjugate gaze palsy varies greatly. Depending on the nature of the lesion, recovery may happen rapidly or recovery may never progress. For example, optic neuritis, which is caused by inflammation, may heal in just weeks, while patients with an ischemic optic neuropathy may never recover.
There are several options of treatment when iatrogenic (i.e., caused by the surgeon) spinal accessory nerve damage is noted during surgery. For example, during a functional neck dissection that injures the spinal accessory nerve, injury prompts the surgeon to cautiously preserve branches of C2, C3, and C4 spinal nerves that provide supplemental innervation to the trapezius muscle. Alternatively, or in addition to intraoperative procedures, postoperative procedures can also help in recovering the function of a damaged spinal accessory nerve. For example, the Eden-Lange procedure, in which remaining functional shoulder muscles are surgically repositioned, may be useful for treating trapezius muscle palsy.
Botulinum toxin is highly effective in the treatment of hemifacial spasm. It has a success rate equal to that of surgery, but repeated injections may be required every 3 to 6 months. The injections are administered as an outpatient or office procedure. Whilst side effects occur, these are never permanent. Repeated injections over the years remain highly effective. Whilst the toxin is expensive, the cost of even prolonged courses of injections compares favourably with the cost of surgery. Patients with HFS should be offered a number of treatment options. Very mild cases or those who are reluctant to have surgery or Botulinum toxin injections can be offered medical treatment, sometimes as a temporary measure. In young and fit patients microsurgical decompression and Botulinum injections should be discussed as alternative procedures. In the majority of cases, and especially in the elderly and the unfit, Botulinum toxin injection is the treatment of first choice. Imaging procedures should be done in all unusual cases of hemifacial spasm and when surgery is contemplated. Patients with hemifacial spasm were shown to have decreased sweating after botulinum toxin injections. This was first observed in 1993 by Khalaf Bushara and David Park. This was the first demonstration of nonmuscular use of BTX-A. Bushara further showed the efficacy of botulinum toxin in treating hyperhidrosis (excessive sweating). BTX-A was later approved for the treatment of excessive underarm sweating. This is technically known as severe primary axillary hyperhidrosis – excessive underarm sweating with an unknown cause which cannot be managed by topical agents (see focal hyperhidrosis).
Aponeurotic and congenital ptosis may require surgical correction if severe enough to interfere with vision or if cosmetics is a concern.
Treatment depends on the type of ptosis and is usually performed by an ophthalmic plastic and reconstructive surgeon, specializing in diseases and problems of the eyelid.
Surgical procedures include:
- Levator resection
- Müller muscle resection
- Frontalis sling operation (preferred option for oculopharyngeal muscular dystrophy)
Non-surgical modalities like the use of "crutch" glasses or Ptosis crutches or special scleral contact lenses to support the eyelid may also be used.
Ptosis that is caused by a disease may improve if the disease is treated successfully, although some related diseases, such as oculopharyngeal muscular dystrophy currently have no treatments or cures.
Medication is used for strabismus in certain circumstances. In 1989, the US FDA approved Botulinum toxin therapy for strabismus in patients over 12 years old. Most commonly used in adults, the technique is also used for treating children, in particular children affected by infantile esotropia. The toxin is injected in the stronger muscle, causing temporary and partial paralysis. The treatment may need to be repeated three to four months later once the paralysis wears off. Common side effects are double vision, droopy eyelid, overcorrection, and no effect. The side effects typically resolve also within three to four months. Botulinum toxin therapy has been reported to be similarly successful as strabismus surgery for people with binocular vision and less successful than surgery for those who have no binocular vision.
The best-studied medical treatment for intracranial hypertension is acetazolamide (Diamox), which acts by inhibiting the enzyme carbonic anhydrase, and it reduces CSF production by six to 57 percent. It can cause the symptoms of hypokalemia (low blood potassium levels), which include muscle weakness and tingling in the fingers. Acetazolamide cannot be used in pregnancy, since it has been shown to cause embryonic abnormalities in animal studies. Also, in human beings it has been shown to cause metabolic acidosis as well as disruptions in the blood electrolyte levels of newborn babies. The diuretic furosemide is sometimes used for a treatment if acetazolamide is not tolerated, but this drug sometimes has little effect on the ICP.
Various analgesics (painkillers) may be used in controlling the headaches of intracranial hypertension. In addition to conventional agents such as paracetamol, a low dose of the antidepressant amitriptyline or the anticonvulsant topiramate have shown some additional benefit for pain relief.
The use of steroids in the attempt to reduce the ICP is controversial. These may be used in severe papilledema, but otherwise their use is discouraged.
Treatment of THS includes immunosuppressives such as corticosteroids (often prednisolone) or steroid-sparing agents (such as methotrexate or azathioprine).
Radiotherapy has also been proposed.
The treatment and management of radial neuropathy can be achieved via the following methods:
- Physical therapy or occupational therapy
- Surgery(depending on the specific area and extent of damage)
- Splinting
The first step in symptom control is drainage of cerebrospinal fluid by lumbar puncture. If necessary, this may be performed at the same time as a diagnostic LP (such as done in search of a CSF infection). In some cases, this is sufficient to control the symptoms, and no further treatment is needed.
The procedure can be repeated if necessary, but this is generally taken as a clue that additional treatments may be required to control the symptoms and preserve vision. Repeated lumbar punctures are regarded as unpleasant by patients, and they present a danger of introducing spinal infections if done too often. Repeated lumbar punctures are sometimes needed to control the ICP urgently if the patient's vision deteriorates rapidly.