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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.
In cases of accommodative esotropia, the eyes turn inward due to the effort of focusing far-sighted eyes, and the treatment of this type of strabismus necessarily involves refractive correction, which is usually done via corrective glasses or contact lenses, and in these cases surgical alignment is considered only if such correction does not resolve the eye turn.
In case of strong anisometropia, contact lenses may be preferable to spectacles because they avoid the problem of visual disparities due to size differences (aniseikonia) which is otherwise caused by spectacles in which the refractive power is very different for the two eyes. In a few cases of strabismic children with anisometropic amblyopia, a balancing of the refractive error eyes via refractive surgery has been performed before strabismus surgery was undertaken.
Early treatment of strabismus when the person is a baby may reduce the chance of developing amblyopia and depth perception problems. However, a review of randomized controlled trials concluded that the use of corrective glasses to prevent strabismus is not supported by existing research. Most children eventually recover from amblyopia if they have had the benefit of patches and corrective glasses. Amblyopia has long been considered to remain permanent if not treated within a critical period, namely before the age of about seven years; however, recent discoveries give reason to challenge this view and to adapt the earlier notion of a critical period to account for stereopsis recovery in adults.
Eyes that remain misaligned can still develop visual problems. Although not a cure for strabismus, prism lenses can also be used to provide some temporary comfort and to prevent double vision from occurring.
The prognosis for each patient with esotropia will depend upon the origin and classification of their condition. However, in general, management will take the following course:
1. Identify and treat any underlying systemic condition.
2. Prescribe any glasses required and allow the patient time to 'settle into' them.
3. Use occlusion to treat any amblyopia present and encourage alternation.
4. Where appropriate, orthoptic exercises can be used to attempt to restore binocularity.
5. Where appropriate, prismatic correction can be used, either temporarily or permanently, to relieve symptoms of double vision.
6. In specific cases, and primarily in adult patients, botulinum toxin can be used either as a permanent therapeutic approach, or as a temporary measure to prevent contracture of muscles prior to surgery
7. Where necessary, extra-ocular muscle surgery can be undertaken to improve cosmesis and, on occasion, restore binocularity.
A comprehensive eye examination including an ocular motility (i.e., eye movement) evaluation and an evaluation of the internal ocular structures will allow an eye doctor to accurately diagnose the exotropia. Although glasses and/or patching therapy, exercises, or prisms may reduce or help control the outward-turning eye in some children, surgery is often required.
There is a common form of exotropia known as "convergence insufficiency" that responds well to orthoptic vision therapy including exercises. This disorder is characterized by an inability of the eyes to work together when used for near viewing, such as reading. Instead of the eyes focusing together on the near object, one deviates outward.
"Consecutive exotropia" is an exotropia that arises after an initial esotropia. Most often it results from surgical overcorrection of the initial esotropia. It can be addressed with further surgery or with vision therapy; vision therapy has shown promising results if the consecutive exotropia is intermittent, alternating and of small magnitude. (Consecutive exotropia may however also spontaneously develop from esotropia, without surgery or botulinum toxin treatment.)
Because of the risks of surgery, and because about 35% of people require at least one more surgery, many people try vision therapy first. This consists of visual exercises. Although vision therapy is generally not covered by American health insurance companies, many large insurers such as Aetna have recently begun offering full or partial coverage in response to recent studies.
Strabismus surgery is sometimes recommended if the exotropia is present for more than half of each day or if the frequency is increasing over time. It is also indicated if a child has significant exotropia when reading or viewing near objects or if there is evidence that the eyes are losing their ability to work as a single unit (binocular vision). If none of these criteria are met, surgery may be postponed pending simple observation with or without some form of eyeglass and/or patching therapy. In very mild cases, there is a chance that the exotropia will diminish with time. The long-term success of surgical treatment for conditions such as intermittent exotropia is not well proven, and surgery can often result in a worsening of symptoms due to overcorrection. Evidence from the available literature suggests that unilateral surgery was more effective than bilateral surgery for individuals affected with intermittent exotropia.
The surgical procedure for the correction of exotropia involves making a small incision in the tissue covering the eye in order to reach the eye muscles. The appropriate muscles are then repositioned in order to allow the eye to move properly. The procedure is usually done under general anesthesia. Recovery time is rapid, and most people are able to resume normal activities within a few days. Following surgery, corrective eyeglasses may be needed and, in many cases, further surgery is required later to keep the eyes straight.
When a child requires surgery, the procedure is usually performed before the child attains school age. This is easier for the child and gives the eyes a better chance to work together. As with all surgery, there are some risks. However, strabismus surgery is usually a safe and effective treatment.
"Congenital esotropia," or "infantile esotropia," is a specific sub-type of primary concomitant esotropia. It is a constant esotropia of large and consistent size with onset between birth and six months of age. It is not associated with hyperopia, so the exertion of accommodative effort will not significantly affect the angle of deviation. It is, however, associated with other ocular dysfunctions including oblique muscle over-actions, Dissociated Vertical Deviation (DVD,) Manifest Latent Nystagmus, and defective abduction, which develops as a consequence of the tendency of those with infantile esotropia to 'cross fixate.' Cross fixation involves the use of the right eye to look to the left and the left eye to look to the right; a visual pattern that will be 'natural' for the person with the large angle esotropia whose eye is already deviated towards the opposing side.
The origin of the condition is unknown, and its early onset means that the affected individual's potential for developing binocular vision is limited. The appropriate treatment approach remains a matter of some debate. Some ophthalmologists favour an early surgical approach as offering the best prospect of binocularity whilst others remain unconvinced that the prospects of achieving this result are good enough to justify the increased complexity and risk associated with operating on those under the age of one year.
When the fusional vergence system can no longer hold back heterophoria, the phoria manifests. In this condition, the eyes deviate from the fixating position.
In order to understand how heterophoria occurs, we must understand of how the eye can maintain proper fixation with non aligned visual axis. Heterophoria is actually the misalignment of the visual axis of both eyes. In other words, one or both eyes are not properly fixated to an object of interest. However, we must know that the eyes have a fusional vergence system which corrects this misalignment.
Exotropia is a form of strabismus where the eyes are deviated outward. It is the opposite of esotropia and usually involves more severe axis deviation than exophoria. People with exotropia often experience crossed diplopia. Intermittent exotropia is a fairly common condition. "Sensory exotropia" occurs in the presence of poor vision. Infantile exotropia (sometimes called "congenital exotropia") is seen during the first year of life, and is less common than "essential exotropia" which usually becomes apparent several years later.
The brain's ability to see three-dimensional objects depends on proper alignment of the eyes. When both eyes are properly aligned and aimed at the same target, the visual portion of the brain fuses the forms into a single image. When one eye turns inward, outward, upward, or downward, two different pictures are sent to the brain. This causes loss of depth perception and binocular vision. There have also been some reports of people that can "control" their afflicted eye. The term is from Greek "exo" meaning "outward" and "trope" meaning "a turning".
Pseudomyopia refers to an intermittent and temporary shift in refractive error of the eye towards myopia, in which the focusing of light in front of the retina is due to a transient spasm of the ciliary muscle causing an increase in the refractive power of the eye. It may be either organic, through stimulation of the parasympathetic nervous system, or functional in origin, through eye strain or fatigue of ocular systems. It is common in young adults who have active accommodation, and classically occurs after a change in visual requirements, such as students preparing for an exam, or a change in occupation.
The major symptom is intermittent blurring of distance vision particularly noticeable after prolonged periods of near work, and symptoms of asthenopia. The vision may clear temporarily using concave (minus) lenses. The diagnosis is done by cycloplegic refraction using a strong cycloplegic like atropine or homatropine eye drops. Accommodative amplitude and facility may be reduced as a result of the ciliary muscle spasm.
Treatment is dependent on the underlying aetiology. Organic causes may include systemic or ocular medications, brain stem injury, or active ocular inflammation such as uveitis. Functional pseudomyopia is managed though modification of working conditions, an updated refraction, typically involving a reduction of a myopic prescription to some lower myopic prescription, or through appropriate ocular exercises.
ONSM does not improve without treatment. In many cases, there is gradual progression until vision is lost in the affected eye. However, this takes at least several months to occur, and a minority of patients remain stable for a number of years.
Most ophthalmologists will not advocate any treatment unless visual loss is present and ongoing. Reports of patients with ONSM having no change in their vision for multiple years are not uncommon. If loss of vision occurs, radiation therapy will improve vision in about ⅓ of cases, and preserve vision in about ⅓ of cases. Surgery has traditionally been associated with rapid deteroriation of vision. However, newer surgical techniques may prove better for the treatment of ONSM.
Currently there is no specific treatment for this condition. Management is supportive.
Several drugs are used to treat DES, including nitroglycerin, hyoscine butylbromide, calcium channel blockers, hydralazine, and anti-anxiety medications. Acid suppression therapy, such as proton pump inhibitors, are often the first line therapy. Botulinum toxin, which inhibits acetylcholine release from nerve endings, injected above the lower esophageal sphincter may also be used in the treatment of DES. Small studies have suggested benefit from endoscopic balloon dilation in certain patients, but all of the above have a low percentage of success in treating the condition; whilst the treatments work in some sufferers, it does not work for everyone. In extremely rare cases, surgery may be considered.
It is diagnosed and treated endoscopically; however, endoscopic ultrasound or angiography can be of benefit.
Endoscopic techniques used in the treatment include epinephrine injection followed by bipolar or monopolar electrocoagulation, injection sclerotherapy, heater probe, laser photocoagulation, hemoclipping or banding. Alternatively, in patients with refractory bleeding Interventional Radiology may be consulted for an angiogram with subselective embolization.
A trial of the anticonvulsant drug carbamazepine is common for patients diagnosed with GN. For patients who do not tolerate or respond to carbamazepine, alternative drugs include oxcarbazepine, gabapentin, phenytoin, lamotrigine, and baclofen. In addition, tricyclics (e.g., amitriptyline) and pregabalin are useful in other types of neuropathic pain.
The mortality rate for Dieulafoy's was much higher before the era of endoscopy, where open surgery was the only treatment option.
The trigger needs to be identified before prescribing anti-epileptics. The most commonly prescribed drugs for reflex epilepsy are valproate, carbamazepine and clonazepam, though lamotrigine, levetiracetam are promising.
Catheterization methods range from intermittent catheterization, which involves no surgery or permanently attached appliances, to the creation of a stoma, which bypasses the urethra to empty the bladder directly.
Intermittent catheterization is the use, several times a day, of straight catheters (which are usually disposable or single-use products) to empty the bladder. This can be done independently by the patient, or with help, in the case that the patient lacks the dexterity to manage the catheter. For patients who are unable to tolerate disposable straight catheters, a Foley catheter allows continuous drainage of urine into a sterile drainage bag that is worn by the patient.
Other treatments involve creation of a stoma that is continent and readily accepts a catheter. These are known as Mitrofanoff mechanisms. An example of this treatment is the creation of an Indiana pouch. Additionally, a muscarinic agonist like Bethanechol may also be used, particularly in the postpartum or postoperative period. Function of the stoma may be augmented by periodic injections of botulinum toxin to relax one of the two sphincters involved in normal urination. The effect is longer-lasting with botulinum toxin type A than with type B. This use of botulinum toxin is discussed at length in the French medical literature.
When in acute urinary retention, treatment of the urethral stricture or diversion is an emergency. Options include:
- Urethral dilatation and catheter placement. This can be performed in the Emergency Department, a practitioner's office or an operating room. The advantage of this approach is that the urethra may remain patent for a period of time after the dilation, though long-term success rates are low.
- Insertion of a suprapubic catheter with catheter drainage system. This procedure is performed in an Operating Room, Emergency Department or practitioner's office. The advantage of this approach is that it does not disrupt the scar and interfere with future definitive surgery.
These hernias should be repaired because of the high risk of strangulation; fortunately, surgery is straightforward, with only larger defects requiring a mesh prosthesis. Varied Spigelian hernia mesh repair techniques have been described, although evidence suggests laparoscopy results in less morbidity and shorter hospitalization compared with open procedures. Mesh-free laparoscopic suture repair is feasible and safe. This novel uncomplicated approach to small Spigelian hernias combines the benefits of laparoscopic localization, reduction, and closure without the morbidity and cost associated with foreign material.
In general, there are two broad classes of treatment, and the two may be combined: psychological (cognitive-behavioral) and pharmacological. In situations of acute distress such as a grief reaction, pharmacologic measures may be most appropriate. With primary insomnia, however, initial efforts should be psychologically based, including discussion of good sleep hygiene. Other specific treatments are appropriate for some of the disorders, such as ingestion of the hormone melatonin, correctly timed bright light therapy and correctly timed dark therapy or light restriction for the circadian rhythm sleep disorders. Specialists in sleep medicine are trained to diagnose and treat these disorders, though many specialize in just some of them.
A permanent urethral stent was approved for use in men with bulbar urethral strictures in 1996, but was recently removed from the market.
A temporary thermoexpandable urethral stent (Memotherm) is available in Europe, but is not currently approved for use in the United States.
In GRA, the hypersecretion of aldosterone and the accompanying hypertension are remedied when ACTH secretion is suppressed by administering glucocorticoids.
Dexamethasone, spironolactone and eplerenone have been used in treatment.
A variety of surgeries have been performed including microvascular decompression (MVD) of the fifth, ninth, and tenth nerves; as well as partial cutting of the nervus intermedius, geniculate ganglion, chorda tympani and/or the ninth and tenth cranial nerves.
Exercise can improve symptoms, as can revascularization. Both together may be better than one intervention of its own.
Pharmacological options exist, as well. Medicines that control lipid profile, diabetes, and hypertension may increase blood flow to the affected muscles and allow for increased activity levels. Angiotensin converting enzyme inhibitors, beta-blockers, antiplatelet agents (aspirin and clopidogrel), naftidrofuryl, pentoxifylline, and cilostazol (selective PDE3 inhibitor) are used for the treatment of intermittent claudication. However, medications will not remove the blockages from the body. Instead, they simply improve blood flow to the affected area.
Catheter-based intervention is also an option. Atherectomy, stenting, and angioplasty to remove or push aside the arterial blockages are the most common procedures for catheter-based intervention. These procedures can be performed by interventional radiologists, interventional cardiologists, vascular surgeons, and thoracic surgeons, among others.
Surgery is the last resort; vascular surgeons can perform either endarterectomies on arterial blockages or perform an arterial bypass. However, open surgery poses a host of risks not present with catheter-based interventions.