Cochlear implant Health Dictionary

(1) The placing of a substance such as a drug, or an object such as a pacemaker, in a body tissue.

(2) The surgical replacement of injured or unhealthy tissue or organ with healthy tissue or organ (also known as TRANSPLANTATION).

(3) Attachment of the early EMBRYO to the lining of the UTERUS, which occurs around six days after conception; the site where this happens is where the placenta will develop.... implantation

An artificial structure surgically introduced into the breast to increase its size (see mammoplasty).... breast implant

Any material, either natural or artificial, inserted into the body for medical or cosmetic purposes. For example, artificial joints can replace diseased structures and breast implants can improve appearance. Implants are also used to maintain proper functioning of an internal organ, treat certain disorders, or deliver drugs or hormones.... implant

A plastic prosthesis used to replace the removed opaque lens in cataract surgery.... lens implant

A cochlear implant is an electronic device, inserted under a general anaesthetic, which stimulates the auditory system, restoring partial hearing in profound sensory deafness. Although there are many types of cochlear implant, they all consist of a microphone, a signal processor, a signal coupler (transmitter and receiver), and an array of electrodes. Most are multi-channel implants. The microphone and signal processor are worn outside the body, like a conventional hearing aid: they receive sound and convert it into an electronic signal which is transmitted through the skin to the receiver. Here the signal is transmitted to the array of electrodes which stimulates the cochlear nerve. Although cochlear implants do not provide normal hearing, most profoundly deaf patients who receive a cochlear implant are able to detect a variety of sounds, including environmental sounds and speech. The duration of hearing-loss and age at implantation are among the many factors which in?uence the results (see DEAFNESS).... cochlear implants

A hormonal method of contraception in which longacting contraceptive drugs are inserted under the skin.

An implant consists of a small rod that steadily releases a progestogen drug into the bloodstream.... contraceptive implant

Attachment of a fertilized ovum (egg) to the wall of the uterus.

It occurs about 6 days after fertilization, when the blastocyst (early embryo) comes into contact with the wall of the uterus.

As the cells of the developing embryo continue to divide, the outer cell layer penetrates the lining of the uterus to obtain oxygen and nutrients from the mother’s blood; later, this layer develops into the placenta.

The embryo usually implants in the upper part of the uterus; if it implants low down near the cervix, placenta praevia may develop.

Rarely, implantation occurs outside the uterus, possibly in a fallopian tube, resulting in an ectopic pregnancy.... implantation, egg

A post, surgically embedded in the jaw for the attachment of a dental prosthesis (an artificial tooth). Titanium or synthetic materials may be used. A dental implant is fitted under local anaesthesia. A hole is drilled in the jaw and a post inserted. Several months later, an attachment that protrudes from the gum is screwed into the post; a few weeks after that, the prosthesis is fitted.... implant, dental

A prosthesis inserted into the penis to help a man suffering from permanent impotence to achieve intercourse.

The various types include a silicone splint inserted in the tissues of the upper surface of the penis, and an inflatable prosthesis that is inflated by squeezing a small bulb in the scrotum.... penile implant

See implants, dental.... titanium dental implants

(scala media) see cochlea.... cochlear duct

the electrical potential generated by the cochlea in response to an acoustic stimulus. It can be detected by *auditory brainstem response audiometry or *electrocochleography and is useful in the diagnosis of *auditory neuropathy spectrum disorder.... cochlear microphonic

(acoustic nerve, auditory nerve) the nerve connecting the cochlea to the brain and therefore responsible for transmitting the nerve impulses relating to hearing. It forms part of the *vestibulocochlear nerve (cranial nerve VIII).... cochlear nerve

see implant.... dental implant

(fetal graft) the introduction of an ovum, fertilized in vitro and developed to the *blastocyst stage, into the uterus of a postmenopausal woman in order that she may become pregnant. Before this procedure, the woman’s uterus must be prepared, by hormone therapy, to receive and nurture the blastocyst. Hormone treatment is continued throughout the pregnancy.... fetal implant

(ICD) a self-contained device, similar to a *pacemaker, that monitors heart rhythm and delivers an electric shock to correct life-threatening arrhythmia. See also defibrillator.... implantable cardiovertor defibrillator

a form of hearing aid in which a small electrical vibrator is surgically attached to the auditory *ossicles. An external device with a microphone and an electronic processing unit passes information to the implanted device using radio-frequency waves. The external part is located behind the pinna and is powered by batteries.... implantable hearing aid

a device similar to a *cochlear implant except that the electrode stimulates the auditory parts of the *brainstem rather than the cochlea. It is used to restore hearing of profoundly deaf people who have had damage to both auditory nerves and are hence unsuitable for cochlear implantation. It consists of an electrode that is permanently implanted on the surface of the brainstem. An external device with a microphone and an electronic processing unit pass information to the electrode using radio-frequency waves. The implant is powered by batteries in the external part of the device. It is most commonly used in patients with *neurofibromatosis type II who have had bilateral *vestibular schwannomas.... auditory brainstem implant

(ILR) a device, inserted beneath the skin of the chest, to record the heart rhythm for up to two years. It is usually used for the investigation of patients presenting with infrequent syncope (fainting) in whom arrhythmia is the suspected cause. When syncope occurs, the device can be examined using wireless technology to reveal the heart rhythm at the time of the episode.... implantable loop recorder

a valved device used in the surgical treatment of some types of glaucoma to control intraocular pressure by allowing fluid to drain from the anterior chamber into the subconjunctival space.... molteno implant

(TAVI) replacement of the aortic valve in patients with *aortic stenosis using a catheter-delivered prosthesis rather than open heart surgery. Usually the catheter is passed via the femoral artery, but sometimes it can be passed via the subclavian artery or through the wall of the left ventricle via a localized *thoracotomy.... transcatheter aortic valve implantation