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There are three treatment options available to a patient. These options are observation, microsurgical removal and radiation (radiosurgery or radiotherapy). Determining which treatment to choose involves consideration of many factors including the size of the tumor, its location, the patient's age, physical health and current symptoms. About 25% of all acoustic neuromas are treated with medical management consisting of a periodic monitoring of the patient's neurological status, serial imaging studies, and the use of hearing aids when appropriate.
One of the last great obstacles in the management of acoustic neuromas is hearing preservation and/or rehabilitation after hearing loss. Hearing loss is both a symptom and concommitant risk, regardless of the treatment option chosen.
Treatment does not restore hearing already lost, though there are a few rare cases of hearing recovery reported.
A diagnosis of NF2 related bilateral acoustic neuromas creates the possibility of complete deafness if the tumors are left to grow unchecked. Preventing or treating the complete deafness that may befall individuals with NF2 requires complex decision making. The trend at most academic U.S. medical centers is to recommend treatment for the smallest tumor which has the best chance of preserving hearing. If this goal is successful, then treatment can also be offered for the remaining tumor. If hearing is not preserved at the initial treatment, then usually the second tumor, in the only-hearing ear, is just observed. If it shows continued growth and becomes life-threatening, or if the hearing is lost over time as the tumor grows, then treatment is undertaken. This strategy has the highest chance of preserving hearing for the longest time possible.
Since acoustic neuromas tend to be slow-growing and are benign tumors, careful observation over a period of time may be appropriate for some patients. When a small tumor is discovered in an older patient, observation to determine the growth rate of the tumor may be indicated if serious symptoms are not present. There is now good evidence from large observational studies that suggest many small tumors in older individuals do not grow, thus allowing tumors with no growth to be observed successfully. If the tumor grows, treatment may become necessary.
Another example of a group of patients for whom observation may be indicated includes patients with a tumor in their only hearing or better hearing ear, particularly when the tumor is of a size that hearing preservation with treatment would be unlikely. In this group of patients, MRI is used to follow the growth pattern. Treatment is recommended if either the hearing is lost or the tumor size becomes life-threatening, thus allowing the patient to retain hearing for as long as possible.
Current studies suggest surgeons should observe small acoustic neuromas (those 1.5 cm or less).
Over a period of 10 years of observation with no treatment, 45% of patients with small tumors (and therefore minimal symptoms) lose functional hearing on the affected side; this percentage is considerably higher than that for patients actively treated with hearing-preserving microsurgery or radiosurgery.
The objective of irradiation is to halt the growth of the acoustic neuroma tumour, it does not excise it from the body, as the term 'radiosurgery' or 'gammaknife' implies. Radiosurgery is only suitable for small to medum size tumors.
There are three modalities of surgical treatment (excision) depending on where the anatomical location of the incision to access the tumor is made: retrosigmoid (a variant of what was formerly called suboccipital), translabyrinthine, and middle fossa.
The goals of surgery are to control the tumor, and preserve hearing as well as facial nerves. Especially in the case of larger tumors, there may be a tradeoff between tumor removal and preservation of nerve functionality.
There are different defined degrees of surgical excision, termed 'subtotal resection', 'radical subtotal resection', 'near-total resection', and 'total resection' in order or increasing proportion of tumor removed. Lesser amount of tumor removal may increase likelihood of preservation of nerve function (hence better post-operative hearing), but also likelihood of tumor regrowth, necessitating additional treatment.
there were no medications effective for tinnitus. There is not enough evidence to determine if antidepressants or acamprosate are useful. While there is tentative evidence for benzodiazepines, it is insufficient to support usage. Anticonvulsants have not been found to be useful. Steroid injections into the middle ear also do not seem to be effective.
Botulinum toxin injection has been tried with some success in some of the rare cases of objective tinnitus from a palatal tremor.
"Ginkgo biloba" does not appear to be effective. The American Academy of Otolaryngology recommends against taking melatonin or zinc supplements to relieve symptoms of tinnitus. In addition, a 2016 Cochrane Review concluded that evidence is not sufficient to support taking zinc supplements to reduce symptoms associated with tinnitus.
There are several different surgical techniques for the removal of acoustic neuroma. The choice of approach is determined by size of the tumour, hearing capability, and general clinical condition of the patient.
- The retrosigmoid approach offers some opportunity for the retention of hearing.
- The translabyrinthine approach will sacrifice hearing on that side, but will usually spare the facial nerve. Post-operative cerebrospinal fluid leaks are more common.
- The middle fossa approach is preferred for small tumours, and offers the highest probability of retention of hearing and vestibular function.
- Less invasive endoscopic techniques have been done outside of the United States for some time. Recovery times are reported to be faster. However, this technique is not yet mainstream among surgeons in the US.
Larger tumors can be treated by either the translabyrinthine approach or the retrosigmoid approach, depending upon the experience of the surgical team. With large tumors, the chance of hearing preservation is small with any approach. When hearing is already poor, the translabyrinthine approach may be used for even small tumors. Small, lateralized tumours in patients with good hearing should have the middle fossa approach. When the location of the tumour is more medial a retrosigmoid approach may be better.
Auditory canal decompression is another surgical technique that can prolong usable hearing when a vestibular schwannoma has grown too large to remove without damage to the cochlear nerve. In the IAC (internal auditory canal) decompression, a middle fossa approach is employed to expose the bony roof of the IAC without any attempt to remove the tumor. The bone overlying the acoustic nerve is removed, allowing the tumour to expand upward into the middle cranial fossa. In this way, pressure on the cochlear nerve is relieved, reducing the risk of further hearing loss from direct compression or obstruction of vascular supply to the nerve.
Radiosurgery is a conservative alternative to cranial base or other intracranial surgery. With conformal radiosurgical techniques, therapeutic radiation focused on the tumour, sparing exposure to surrounding normal tissues. Although radiosurgery can seldom completely destroy a tumor, it can often arrest its growth or reduce its size. While radiation is less immediately damaging than conventional surgery, it incurs a higher risk of subsequent malignant change in the irradiated tissues, and this risk in higher in NF2 than in sporadic (non-NF2) lesions.
Early diagnosis allows better planning of therapy in young patients with NF II. In many cases, the hearing loss is present for 10 years before the correct diagnosis is established. Early in the condition, surgery for an acoustic neurinoma can protect facial nerve function in many patients. In selected cases of patients with very small tumors and good bilateral hearing, surgery may offer the possibility of long-term hearing preservation.
Patients with the Wishard phenotype suffer multiple recurrences of the tumour after surgical treatment. In the case of facial nerve palsy, the muscles of the eyelids can lose their mobility, leading to conjunctivitis and corneal injury. "Lidloading" (implantation of small magnets, gold weights, or springs in the lid) can help prevent these complications. Other means of preserving corneal health include tarsorrhaphy, where the eyelids are partially sewn together to narrow the opening of the eye, or the use of punctal plugs, which block the duct that drains tears from the conjunctival sac. All these techniques conserve moisture from the lacrymal glands, which lubricates the cornea and prevents injury. Most patients with NF II develop cataracts, which often require replacement of the lens. Children of affected parents should have a specialist examination every year to detect developing tumors. Learning of sign language is one means of preparation for those that will most probably suffer complete hearing loss.
Definitive treatment depends on the underlying cause of vertigo. Ménière's disease patients have a variety of treatment options to consider when receiving treatment for vertigo and tinnitus including: a low-salt diet and intratympanic injections of the antibiotic gentamicin or surgical measures such as a shunt or ablation of the labyrinth in refractory cases.
Common drug treatment options for vertigo may include the following:
- Anticholinergics such as hyoscine hydrobromide (scopolamine)
- Anticonvulsants such as topiramate or valproic acid for vestibular migraines
- Antihistamines such as betahistine, dimenhydrinate, or meclizine, which may have antiemetic properties
- Beta blockers such as metoprolol for vestibular migraine
- Corticosteroids such as methylprednisolone for inflammatory conditions such as vestibular neuritis or dexamethasone as a second-line agent for Ménière's disease
All cases of decompression sickness should be treated initially with 100% oxygen until hyperbaric oxygen therapy (100% oxygen delivered in a high-pressure chamber) can be provided. Several treatments may be necessary, and treatment will generally be repeated until either all symptoms resolve, or no further improvement is apparent.
Earlier workers suggested the use of calcium fluoride; now sodium fluoride is the preferred compound. Fluoride ions inhibit the rapid progression of disease. In the otosclerotic ear, there occurs formation of hydroxylapatite crystals which lead to stapes (or other) fixation. The administration of fluoride replaces the hydroxyl radical with fluoride leading to the formation of fluorapatite crystals. Hence, the progression of disease is considerably slowed down and active disease process is arrested.
This treatment cannot reverse conductive hearing loss, but may slow the progression of both the conductive and sensorineural components of the disease process. Otofluor, containing sodium fluoride, is one treatment. Recently, some success has been claimed with a second such treatment, bisphosphonate medications that inhibit bone destruction. However, these early reports are based on non-randomized case studies that do not meet standards of clinical trials. There are numerous side-effects to both pharmaceutical treatments, including occasional stomach upset, allergic itching, and increased joint pains which can lead to arthritis. In the worst case, bisphosphonates may lead to osteonecrosis of the auditory canal itself. Finally, neither approach has been proven to be beneficial after the commonly preferred method of surgery has been undertaken.
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.
Treatment options that offer “cures” for NIHL are under research and development. Currently there are no commonly used cures, but rather assistive devices and therapies to try and manage the symptoms of NIHL.
Sedative drugs are often prescribed for vertigo and dizziness, but these usually treat the symptoms rather than the underlying cause. Lorazepam (Ativan) is often used and is a sedative which has no effect on the disease process, but rather helps patients cope with the sensation.
Anti-nauseants, like those prescribed for motion sickness, are also often prescribed but do not affect the prognosis of the disorder.
Specifically for Meniere's disease a medication called Serc (Beta-histine) is available. There is some evidence to support its effectiveness in reducing the frequency of attacks. Also Diuretics, like Diazide (HCTZ/triamterene), are effective in many patients. Finally, ototoxic medications delivered either systemically or through the eardrum can eliminate the vertigo associated with Meniere's in many cases, although there is about a 10% risk of further hearing loss when using ototoxic medications.
Treatment is specific for underlying disorder of balance disorder:
- anticholinergics
- antihistamines
- benzodiazepines
- calcium channel antagonists, specifically Verapamil and Nimodipine
- GABA modulators, specifically gabapentin and baclofen
- Neurotransmitter reuptake inhibitors such as SSRIs, SNRIs and Tricyclics
Several clinical trials have been conducted to treat temporary NIHL occurring after a traumatic noise event, such as a gunshot or firework. In 2007, individuals with acute acoustic trauma after firecracker exposure were injected intratympanically with a cell permeable ligand, AM-111. The trial found AM-111 to have a therapeutic effect on at least 2 cases of those with acute trauma. Treatment with a combination of prednisolone and piracetam appeared to rescue patients with acute trauma after exposure to gunshots. However, those who received the treatment within an hour of exposure had higher rates of recovery and significantly lower threshold shifts compared to those who received treatment after 1 hour.
Additionally, clinical trials using antioxidants after a traumatic noise event to reduce reactive oxygen species have displayed promising results. Antibiotic injections with allopurinol, lazaroids, α-D-tocopherol, and mannitol were found to reduce the threshold shift after noise exposure. Another antioxidant, Ebselen, has been shown to have promising results for both TTS and PTS. Ebselen mimics gluthathione peroxide, an enzyme that has many functions, including scavenging hydrogen peroxide and reactive oxygen species. After noise exposure, gluthathione peroxide decreases in the ear. An oral administration of ebselen in both preclinical tests on guinea pigs and human trials indicate that noise induced TTS and PTS was reduced.
One possible treatment for hyperacusis is retraining therapy which uses broadband noise. Tinnitus retraining therapy, a treatment originally used to treat tinnitus, uses broadband noise to treat hyperacusis. Pink noise can also be used to treat hyperacusis. By listening to broadband noise at soft levels for a disciplined period of time each day, patients can rebuild (i.e., re-establish) their tolerances to sound.
Another possible treatment is cognitive behavioral therapy (CBT), which may also be combined with retraining therapy.
Although hearing aids cannot prevent, cure or inhibit the progression of otosclerosis, they can help treat the largest symptom, hearing loss. Hearing aids can be tuned to specific frequency losses. However, due to the progressive nature of this condition, use of a hearing aid is palliative at best. Without eventual surgery, deafness is likely to result.
Dysequilibrium arising from bilateral loss of vestibular function – such as can occur from ototoxic drugs such as gentamicin – can also be treated with balance retraining exercises (vestibular rehabilitation) although the improvement is not likely to be full recovery.
Surgical removal of tumors is an option, however the risks involved should be assessed first. With regard to OPG (optic pathway gliomas), the preferred treatment is chemotherapy. However, radiotherapy isn't recommended in children who present with this disorder. It is recommended that children diagnosed with NF1 at an early age have an examination each year, which allows any potential growths or changes related to the disorder to be monitored.
Treatment modalities fall into three categories: pharmacological, surgical, and management. As SNHL is a physiologic degradation and considered permanent, there are as of this time, no approved or recommended treatments.
There have been significant advances in identification of human deafness genes and elucidation of their cellular mechanisms as well as their physiological function in mice. Nevertheless, pharmacological treatment options are very limited and clinically unproven. Such pharmaceutical treatments as are employed are palliative rather than curative, and addressed to the underlying cause if one can be identified, in order to avert progressive damage.
Profound or total hearing loss may be amenable to management by cochlear implants, which stimulate cochlear nerve endings directly. A cochlear implant is surgical implantation of a battery powered electronic medical device in the inner ear. Unlike hearing aids, which make sounds louder, cochlear implants do the work of damaged parts of the inner ear (cochlea) to provide sound signals to the brain. These consist of both internal implanted electrodes and magnets and external components. The quality of sound is different than natural hearing but may enable the recipient to better recognize speech and environmental sounds.
Because of risk and expense, such surgery is reserved for cases of severe and disabling hearing impairment
Management of sensorineural hearing loss involves employing strategies to support existing hearing such as lip-reading, enhanced communication etc. and amplification using hearing aids. Hearing aids are specifically tuned to the individual hearing loss to give maximum benefit.
About half of people with SSNHL will recover some or all of their hearing spontaneously, usually within one to two weeks from onset. Eighty-five percent of those who receive treatment from an otolaryngologist (sometimes called an ENT) will recover some of their hearing.
- vitamins and antioxidants
- vasodilators
- betahistine (Betaserc), an anti-vertigo drug
- hyperbaric oxygen
- anti-inflammatory agents, primarily oral corticosteroids such as prednisone, methylprednisone
- Intratympanic administration - Gel formulations are under investigation to provide more consistent drug delivery to the inner ear. Local drug delivery can be accomplished through intratympanic administration, a minimally invasive procedure where the ear drum is anesthetized and a drug is administered into the middle ear. From the middle ear, a drug can diffuse across the round window membrane into the inner ear. Intratympanic administration of steroids may be effective for sudden sensorineural hearing loss for some patients, but high quality clinical data has not been generated. Intratympanic administration of an anti-apoptotic peptide (JNK inhibitor) is currently being evaluated in late-stage clinical development.
As of 2012 there has only been one small-scale study comparing CROS systems.
One study of the BAHA system showed a benefit depending on the patient's transcranial attenuation. Another study showed that sound localisation was not improved, but the effect of the head shadow was reduced.
Medical and surgical treatments have been recommended to treat organic dysphonias. An effective treatment for spasmodic dysphonia (hoarseness resulting from periodic breaks in phonation due to hyperadduction of the vocal folds) is botulinum toxin injection. The toxin acts by blocking acetylcholine release at the thyro-arytenoid muscle. Although the use of botlinum toxin injections is considered relatively safe, patients' responses to treatment differ in the initial stages; some have reported experiencing swallowing problems and breathy voice quality as a side-effect to the injections. Breathiness may last for a longer period of time for males than females.
Surgeries involve myoectomies of the laryngeal muscles to reduce voice breaks, and laryngoplasties, in which laryngeal cartilage is altered to reduce tension.
Indirect therapies take into account external factors that may influence vocal production. This incorporates maintenance of vocal hygiene practices, as well as the prevention of harmful vocal behaviours. Vocal hygiene includes adequate hydration of the vocal folds, monitoring the amount of voice use and rest, avoidance of vocal abuse (e.g., shouting, clearing of the throat), and taking into consideration lifestyle choices that may affect vocal health (e.g., smoking, sleeping habits). Vocal warm-ups and cool-downs may be employed to improve muscle tension and decrease risk of injury before strenuous vocal activities. It should be taken into account that vocal hygiene practices alone are minimally effective in treating dysphonia, and thus should be paired with other therapies.
Uterine fibroids can be treated with the same methods like sporadic uterine fibroids including antihormonal treatment, surgery or embolisation. Substantially elevated risk of progression to or independent development of uterine leiomyosarcoma has been reported which may influence treatment methods.
The predisposition to renal cell cancer calls for screening and, if necessary, urological management.
The skin lesions may be difficult to treat as they tend to recur after excision or destructive treatment. Drugs which affect smooth muscle contraction, such as doxazosin, nitroglycerine, nifedipine and phenoxybenzamine, may provide pain relief.
Topical lidocaine patches have been reported to decrease in severity and frequency of pain cutaneous leiomyomas.
There are many methods of attempting to reduce the risk of AS. Several devices attempt to remove potentially harmful sound signals by digital signal processing. None has yet been shown to be fully effective. Devices which solely limit noise levels to about 85 dB have been shown in field trials to be ineffective (data from these trials has not been released into the public domain). Limiting background noise and office stress may also reduce the chance of an Acoustic Shock. Proper use of the headset and preventing mobile phones from being used in call centers reduces the chance of feedback.