Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Cholesteatoma is a persistent disease. Once the diagnosis of cholesteatoma is made in a patient who can tolerate a general anesthetic, the standard treatment is to surgically remove the growth.
The challenge of cholesteatoma surgery is to permanently remove the cholesteatoma whilst retaining or reconstructing the normal functions of the structures housed within the temporal bone.
The general objective of cholesteatoma surgery has two parts. It is both directed against the underlying pathology and directed towards maintaining the normal functions of the temporal bone. These aims are conflicting and this makes cholesteatoma surgery extremely challenging.
Sometimes, the situation results in a clash of surgical aims. The need to fully remove a progressive disease like cholesteatoma is the surgeon's first priority. Preservation of hearing is secondary to this primary aim. If the disease can be removed easily so that there is no increased risk of residual disease, then the ossicles may be preserved. If the disease is difficult to remove, so that there is an increased risk of residual disease, then removal of involved ossicles in order to fully clear cholesteatoma has generally been regarded as necessary and reasonable.
In other words, the aims of cholesteatoma treatment form a hierarchy. The paramount objective is the complete removal of cholesteatoma. The remaining objectives, such as hearing preservation, are subordinate to the need for complete removal of cholesteatoma. This hierarchy of aims has led to the development of a wide range of strategies for the treatment of cholesteatoma.
Various strategies may be used to manage tympanic membrane retraction, with the aims of preventing or relieving hearing loss and cholesteatoma formation.
As retraction pockets may remain stable or resolve spontaneously, it may be appropriate to observe them for a period of time before considering any active treatment.
The variation in technique in cholesteatoma surgery results from each surgeon's judgment whether to retain or remove certain structures housed within the temporal bone in order to facilitate the removal of cholesteatoma. This typically involves some form of mastoidectomy which may or may not involve removing the posterior ear canal wall and the ossicles.
Removal of the canal wall facilitates the complete clearance of cholesteatoma from the temporal bone in three ways:
1. it removes a large surface onto which cholesteatoma may be adherent;
2. it removes a barrier behind which the cholesteatoma may be hidden;
3. it removes an impediment to the introduction of instruments used for the removal of cholesteatoma.
Thus removal of the canal wall provides one of the most effective strategies for achieving the primary aim of cholesteatoma surgery, the complete removal of cholesteatoma. However, there is a trade-off, since the functional impact of canal wall removal is also important.
The removal of the ear canal wall results in:
- a space, the "mastoid cavity", which is less likely than the original ear canal to resist infection;
- exposure of the ossicles, which may allow the subsequent formation of a new cholesteatoma deep to the ossicles. To prevent this, these ossicles must be removed, which may diminish the patient's hearing.
The formation of a mastoid cavity by removal of the canal wall is the simplest and most effective procedure for facilitating the removal of cholesteatoma, but may bestow the most lasting infirmity due to loss of ear function upon the patient treated in this way.
The following strategies are employed to mitigate the effects of canal wall removal:
1. careful design and construction of the mastoid cavity. This is essential for the health and integrity of the protective sheet of migrating, keratising epithelium which lines the distorted ear canal. This requires the surgeon to saucerise the cavity. A high facial ridge and an inappropriately small cartilaginous meatus are obstructions to epithelial migration and are particularly high risk factors for failure of the self-cleaning mechanism of the external ear.
2. partial obliteration of the mastoid cavity. This can be performed using a wide range of materials. Many of these resorb in time, which means that the long-term results of such surgery are poorer than the short-term results.
3. reconstruction of the ear canal wall. Canal wall reconstruction has been performed using ear canal skin alone, fascia, cartilage, titanium as well as by replacing the original intact wall. If the reconstruction is poorly performed, it may result in a high rate of recurrent cholesteatoma.
4. preservation of the ear canal wall. If poorly performed, it may result in a high rate of both residual and recurrent cholesteatoma.
5. reconstruction of the chain of hearing bones.
Clearly, preservation and restoration of ear function at the same time as total removal of cholesteatoma requires a high level of surgical expertise.
Patients are advised to treat with bed rest and avoiding activities that increase intracranial pressure (i.e. weightlifting, valsalva, scuba diving, flying in airplanes) with the hopes of the membrane healing on their own. Appropriate Physical therapy / vestibular rehabilitation techniques can be helpful in managing symptoms of movement sensitivity.
Myringosclerosis seems to be more common than tympanosclerosis. Most research has not been conducted upon the general, healthy population, but rather those with otitis media or patients who have had tympanostomy tubes in prior procedures. Of the children studied who had 'glue ear', and who were treated with tympanostomy tubing, 23-40% of cases had tympanosclerosis. One study suggested that people with atherosclerosis were more likely to have tympanosclerosis than otherwise healthy individuals.
When diagnosing, PLF should be differentiated from Ménière's disease. Tympanostomy has been reported to be a way to diagnose and cure PLF.
Hearing aids are a common treatment for hearing loss disorders. A more specific treatment is surgical, involving excision of the sclerotic areas and then further repair of the ossicular chain. There are several techniques, sometimes involving two surgeries; success rates are, however, variable. Damage to the inner ear as a result of surgical procedures is a possible and serious concern, as it can result in forms of sensorineural deafness.
Long-term antibiotics, while they decrease rates of infection during treatment, have an unknown effect on long-term outcomes such as hearing loss. This method of prevention has been associated with emergence of antibiotic-resistant otitic bacteria. They are thus not recommended.
Pneumococcal conjugate vaccines (PCV) in early infancy, decreases the risk of acute otitis media in healthy infants. PCV is recommended for all children, and, if implemented broadly, PCV would have a significant public health benefit. Influenza vaccine is recommended annually for all children. PCV does not appear to decrease the risk of otitis media when given to high-risk infants or for older children who have previously experienced otitis media.
Risk factors such as season, allergy predisposition and presence of older siblings are known to be determinants of recurrent otitis media and persistent middle-ear effusions (MEE). History of recurrence, environmental exposure to tobacco smoke, use of daycare, and lack of breastfeeding have all been associated with increased risk of development, recurrence, and persistent MEE. Thus, cessation of smoking in the home should be encouraged, daycare attendance should be avoided or daycare facilities with the fewest attendees should be recommended, and breastfeeding should be promoted.
There is some evidence that breastfeeding for the first year of life is associated with a reduction in the number and duration of OM infections. Pacifier use, on the other hand, has been associated with more frequent episodes of AOM.
Evidence does not support zinc supplementation as an effort to reduce otitis rates except maybe in those with severe malnutrition such as marasmus.
Oral and topical pain killers are effective to treat the pain caused by otitis media. Oral agents include ibuprofen, paracetamol (acetaminophen), and opiates. Topical agents shown to be effective include antipyrine and benzocaine ear drops. Decongestants and antihistamines, either nasal or oral, are not recommended due to the lack of benefit and concerns regarding side effects. Half of cases of ear pain in children resolve without treatment in three days and 90% resolve in seven or eight days. The use of steroids is not supported by the evidence for acute otitis media.
Management falls into three modalities: surgical treatment, pharmaceutical treatment, and supportive, depending on the nature and location of the specific cause.
In cases of infection, antibiotics or antifungal medications are an option. Some conditions are amenable to surgical intervention such as middle ear fluid, cholesteatoma, otosclerosis. If conductive hearing loss is due to head trauma, surgical repair is an option. If absence or deformation of ear structures cannot be corrected, or if the patient declines surgery, hearing aids which amplify sounds are a possible treatment option. Bone conduction hearing aids are useful as these deliver sound directly, through bone, to the cochlea or organ of hearing bypassing the pathology. These can be on a soft or hard headband or can be inserted surgically, a bone anchored hearing aid, of which there are several types. Conventional air conduction hearing aids can also be used.
If ear infections are treated in a reasonable amount of time, the antibiotics will usually cure the infection and prevent its spread. For this reason, mastoiditis is rare in developed countries. Most ear infections occur in infants as the eustachian tubes are not fully developed and don't drain readily.
In all developed countries with up-to-date modern healthcare the primary treatment for mastoiditis is administration of intravenous antibiotics. Initially, broad-spectrum antibiotics are given, such as ceftriaxone. As culture results become available, treatment can be switched to more specific antibiotics directed at the eradication of the recovered aerobic and anaerobic bacteria. Long-term antibiotics may be necessary to completely eradicate the infection. If the condition does not quickly improve with antibiotics, surgical procedures may be performed (while continuing the medication). The most common procedure is a myringotomy, a small incision in the tympanic membrane (eardrum), or the insertion of a tympanostomy tube into the eardrum. These serve to drain the pus from the middle ear, helping to treat the infection. The tube is extruded spontaneously after a few weeks to months, and the incision heals naturally. If there are complications, or the mastoiditis does not respond to the above treatments, it may be necessary to perform a mastoidectomy: a procedure in which a portion of the bone is removed and the infection drained.
With prompt treatment, it is possible to cure mastoiditis. Seeking medical care early is important. However, it is difficult for antibiotics to penetrate to the interior of the mastoid process and so it may not be easy to cure the infection; it also may recur. Mastoiditis has many possible complications, all connected to the infection spreading to surrounding structures. Hearing loss is likely, or inflammation of the labyrinth of the inner ear (labyrinthitis) may occur, producing vertigo and an ear ringing may develop along with the hearing loss, making it more difficult to communicate. The infection may also spread to the facial nerve (cranial nerve VII), causing facial-nerve palsy, producing weakness or paralysis of some muscles of facial expression, on the same side of the face. Other complications include Bezold's abscess, an abscess (a collection of pus surrounded by inflamed tissue) behind the sternocleidomastoid muscle in the neck, or a subperiosteal abscess, between the periosteum and mastoid bone (resulting in the typical appearance of a protruding ear). Serious complications result if the infection spreads to the brain. These include meningitis (inflammation of the protective membranes surrounding the brain), epidural abscess (abscess between the skull and outer membrane of the brain), dural venous thrombophlebitis (inflammation of the venous structures of the brain), or brain abscess.
Conductive hearing loss occurs when there is a problem conducting sound waves anywhere along the route through the outer ear, tympanic membrane (eardrum), or middle ear (ossicles).
This type of hearing loss may occur in conjunction with sensorineural hearing loss (mixed hearing loss) or alone.
Since this lesion is usually a complication of long standing otitis media, it is important to use an appropriate antibiotic therapy regimen. If the patient fails first line antibiotics, then second-line therapies should be employed, especially after appropriate culture and sensitivity testing. Surgery may be required if there is extension into the mastoid bone, or if a concurrent cholesteatoma is identified during surgery or biopsy. In general, patients have an excellent outcome after appropriate therapy.
This is an uncommon lesion, usually affecting young patients (mean age, 30 years), with a male to female ratio of 2:1. The middle ear is involved, although it may extend to the external auditory canal if there is tympanic membrane perforation.
The tumor must be removed with as complete a surgical excision as possible. In nearly all cases, the ossicular chain must be included if recurrences are to be avoided. Due to the anatomic site of involvement, facial nerve paralysis and/or paresthesias may be seen or develop; this is probably due to mass effect rather than nerve invasion. In a few cases, reconstructive surgery may be required. Since this is a benign tumor, no radiation is required. Patients experience an excellent long term outcome, although recurrences can be seen (up to 15%), especially if the ossicular chain is not removed. Although controversial, metastases are not seen in this tumor. There are reports of disease in the neck lymph nodes, but these patients have also had other diseases or multiple surgeries, such that it may represent iatrogenic disease.
Most individuals come to clinical attention during the 5th decade, although the age range is broad (20 to 80 years). There is an equal gender distribution.
Reactivation of herpes zoster virus, as well as being associated with Bell's palsy, may also be a direct cause of facial nerve palsy. Reactivation of latent virus within the dorsal root ganglion of the facial nerve is associated with vesicles affecting the ear canal, and termed Ramsay Hunt syndrome type II. In addition to facial paralysis, symptoms may include ear pain and vesicles, sensorineural hearing loss, and vertigo. Management includes Antiviral drugs and oral steroids.
Otitis media is an infection in the middle ear, which can spread to the facial nerve and inflame it, causing compression of the nerve in its canal. Antibiotics are used to control the otitis media, and other options include a wide myringotomy (an incision in the tympanic membrane) or decompression if the patient does not improve.
Chronic otitis media usually presents in an ear with chronic discharge (otorrhea), or hearing loss, with or without ear pain (otalgia). Once suspected, there should be immediate surgical exploration to determine if a cholesteatoma has formed as this must be removed if present. Inflammation from the middle ear can spread to the canalis facialis of the temporal bone - through this canal travels the facial nerve together with the steatoacoustisus nerve. In the case of inflammation the nerve is exposed to edema and subsequent high pressure, resulting in a periferic type palsy.
Lyme disease, caused by chronic "Borrelia burgdorferi" infection, is a common cause of facial nerve paralysis in areas.
Bell's palsy is the most common cause of acute facial nerve paralysis. There is no known cause of Bell's palsy, although it has been associated with herpes simplex infection. Bell's palsy may develop over several days, and may last several months, in the majority of cases recovering spontaneously. It is typically diagnosed clinically, in patients with no risk factors for other causes, without vesicles in the ear, and with no other neurological signs. Recovery may be delayed in the elderly, or those with a complete paralysis. Bell's palsy is often treated with corticosteroids.
Microvascular decompression appears to be the most popular surgical treatment at present. Microvascular decompression relieves pressure on the facial nerve, which is the cause of most hemifacial spasm cases. Excellent to good results are reported in 80% or more cases with a 10% recurrence rate. In the present series approximately 10% had previously failed surgery. Serious complications can follow microsurgical decompressive operations, even when performed by experienced surgeons. These include cerebellar haematoma or swelling, brain stem infarction (blood vessel of the brain stem blocked), cerebral infarction (ischemic stroke resulting from a disturbance in the blood vessels supplying blood to the brain), subdural haematoma and intracerebral infarction (blockage of blood flow to the brain). Death or permanent disability (hearing loss) can occur in 2% of patients of hemifacial spasm.
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.
Clonidine is an alpha receptor agonist that helps reduces sympathetic activity leaving the hypothalamus and reduces circulating catecholamines. It is helpful in lowering blood pressure and heart rate, but it does not show much of an effect on other symptoms. It may also increase sympathetic inhibition in the brainstem. Bromocriptine is a dopamine agonist that helps lower blood pressure. Its effects are modest, but they are not well understood. Baclofen is a GABA agonist that helps control muscle spasms, proving to be helpful in treating dystonia. Benzodiazepines bind to GABA receptors and work as muscle relaxants. Benzodiazepines also combat high blood pressure and respiratory rates; however, they are associated with glaucoma, which is a rather serious side effect. Gabapentin inhibits neurotransmitter release in the dorsal horn of the spinal cord and various areas of the central nervous system. It helps treat mild symptoms and can be tolerated for longer periods of time compared to other drug treatments. Dantrolene helps combat dystonia and fever by affecting muscle contraction and relaxation cycles. It hinders the release of calcium from the sarcoplasmic reticulum, inhibiting muscle contraction. It causes decreases in respiration, but it can be very dangerous for the liver. Again, these treatments are seen case by case and treat symptoms well. They do not treat the syndrome as a whole or preventatively. Efficacy varies patient to patient, as symptoms do.
Non-selective beta-blockers are the most effective in reducing the frequency and severity of PSH episodes. They help decrease the effect of circulating catecholamines and lower metabolic rates, which are high in patients during PSH episodes. Beta-blockers also help in reducing fever, diaphoresis, and in some cases dystonia. Propanolol is a common beta-blocker administered due to the fact that it penetrates the blood-brain barrier relatively well. Typically it is administered in doses of twenty milligrams to sixty milligrams every four to six hours in the treatment of PSH.