Tinnitus is a phantom sound people start to hear when hearing loss develops. Once it starts, it does not go completely away, but things can be done to make it manageable, other things can make tinnitus worse.
There are different forms of tinnitus that if not managed can cause different additional issues. Included are reasons for tinnitus, and means of tinnitus management.
Unfortunately, tinnitus remains after an ear can no longer hear.
There are multiple forms of Tinnitus, each caused by different issues and might result in different sound or sounds.
All forms of Tinnitus get worse with stress.
Schwannoma tumor damage of both the Vestibular Nerve (balance) and Cochlear Nerve (hearing), called Vestibular Schwannoma (VS), the hallmark tumor of individuals with Neurofibromatosis Type 2 (NF2), slowly starts as Subjective Tinnitus before the development of Deafness.
When Tinnitus starts, it is important to see an Otolaryngologist also known as ENT (Ear Nose and Throat Doctor) immediately and Neurologist for an MRI.
Subjective tinnitus is a common hearing disorder with a potentially devastating impact on the Quality of Life, characterized by sound perception in the absence of an acoustic stimulus. 
Unfortunately completely severing the Cochlear Nerve will not be the end of the Tinnitus. Subjective Tinnitus is a sound that has no external source. Sounds might include:
Gaze-modulated Tinnitus (GET); can be a result of single sided Vestibular Schwannoma removal and does not need to be bilaterally occurring to happen. It is similar to Phantom Limb Syndrome (Deprivation of sensory input) where eye movement results in different sounds that only the individual with GET can hear. Eye movement in different directions can change volume and tone of the sound.
There are additional forms of Tinnitus unlikely to result from NF2 issues that are a result of either other conditions, loud noises or medications. Objective Tinnitus is a health related form, also unlikely for NF2, Vestibular Schwannoma damage.
Objective Tinnitus (Pulsatile Tinnitus) is an internal sound that usually has the same rate as the heart. This is easily checked by feeling the pulse at the same time as listening to the tinnitus.
Pulsatile tinnitus is due to a change in blood flow in the vessels near the ear or to a change in awareness of that blood flow. The involved vessels include the large arteries and veins in the neck and base of the skull and smaller ones in the ear itself.
Tests for hearing loss include volume and pitch of sound but also include word recognition since there is no other way to determine the actual volume of Tinnitus sounds.
Fear of loud sound. The volume of what is considered loud would change as hearing loss or level of Tinnitus gets worse.
Fear of a certain range of sound.
Hatred of sound of a certain type. Not limited to volume or pitch.
Focusing on Tinnitus results in an endless cycle of stress, headaches, and louder seeming Tinnitus levels.
It has been debatable for some time if this is or is not a problem. But, a study at the Deafness Institute in the UK concluded it is not a Tinnitus trigger.
However, Tinnitus can be worse at nighttime when trying to sleep, so avoiding caffeine a few hours before bedtime can help.
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