What is endolymphatic sac?

The endolymphatic sac is a non-sensory organ of the inner ear. It is connected to the endolymphatic compartment that is filled with endolymph, a potassium-rich fluid that bathes the apical side of inner ear sensory cells.

What causes Eva?

The most well-known cause of EVA and hearing loss is mutations in a gene called SLC26A4 (previously known as the PDS gene). Two mutations in the SLC26A4 gene can result in Pendred syndrome. Scientists believe that other, currently unknown, genetic or environmental factors also may lead to EVA.

What is Eva syndrome?

Enlarged vestibular aqueduct (EVA) syndrome is a common congenital inner ear malformation characterized by a vestibular aqueduct with a diameter larger than 1.5 mm, mixed or sensorineural hearing loss that ranges from mild to profound, and vestibular disorders that may be present with a range from mild imbalance to …

How is Eva diagnosed?

Diagnosis is usually done by positively identifying EVA on a CT scan, or confirming an enlarged endolymphatic duct and sac on high-resolution MRI. Thyroid, renal, and cardiac function may also be analyzed, and genetic screening is sometimes also performed.

How do you drain an endolymphatic sac?

During the procedure, your doctor will make an incision behind the ear and open the mastoid bone. The bone will be removed to reveal the endolymphatic sac. The bone is then removed from the sac and a laser will cut a hole in the outer layer of the sac. A shunt will be inserted into the sac.

Where is the endolymphatic sac?

The vestibular aqueduct (red) houses the endolymphatic duct (ED) and sac. The sac consists of an intraosseous part located inside the temporal bone and an extra-osseous part located on the posterior slope of the petrous pyramid within the dura.

Is enlarged vestibular aqueduct progressive?

Objective: Enlarged vestibular aqueduct is the most common radiographically identified cause of congenital sensorineural hearing loss and is frequently progressive.

How is Eva treated?

Although there is no specific treatment for EVA, care should include rest and, in selected cases, antibiotics, which may decrease the risk of secondary bacterial infection. Adult horses recover completely from the clinical disease.

What is a endolymphatic sac decompression?

Endolymphatic sac decompression is a treatment that is performed to maintain the hydrostatic pressure and endolymph homeostasis in the inner ear for patients with Meniere’s disease. This procedure can reverse the damage to the ear while maintaining the balance of your hearing levels.

What is Endolymphatic sac decompression?

Which fluid is present in ear?

Within the inner ear, there are two types of fluid — endolymph (inner fluid), and perilymph (outer fluid), separated by a membrane.

What is an enlarged endolymphatic duct and SAC?

Large vestibular aqueduct syndrome, or enlarged endolymphatic duct (EED) and sac (EES) syndrome, is an inner ear malformation that manifests as progressive sensorineural hearing loss starting in infancy or childhood (1–3).

How to diagnose an endolymphatic sac tumor?

Endolymphatic sac tumor 1 Epidemiology. Typically endolymphatic sac tumors are encountered in young individuals, with a mean age at onset is 22 years 2. 2 Clinical presentation 3 Pathology 4 Radiographic features. 5 Treatment and prognosis. 6 History and etymology. 7 Differential diagnosis

Are there endolymphatic sac tumors in von Hippel-Lindau disease?

However, in ~60% of patients with von Hippel-Lindau disease and vestibulocochlear symptoms, there is no evidence on imaging of an endolymphatic sac tumor 2. When these tumors are present in the setting of von Hippel-Lindau disease, then 30% of tumors are bilateral 2.

Are there endolymphatic sac tumors in VHL 2?

Endolymphatic tumors are most often associated with von Hippel-Lindau disease (vHL) and are detected in 11-16% patients with vHL 2. However, in ~60% of patients with vHL and vestibulocochlear symptoms, there is no evidence on imaging of an endolymphatic sac tumor 2.