Question:
Where will be the placement location for an Auditory Brainstem Implant (ABI)?
Where will be the placement location for an Auditory Brainstem Implant (ABI)?
Show Hint
The ABI skips the cochlear nerve and stimulates the cochlear nucleus, whose surface lies in the lateral recess of the 4th ventricle.
Updated On: Jun 23, 2026
- Scala tympani
- Recess of 4th ventricle
- Internal auditory canal (IAC)
- Back of ear
Show Solution
Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: An Auditory Brainstem Implant (ABI) bypasses the cochlea and the cochlear nerve entirely and stimulates the cochlear nucleus directly within the brainstem. It is mainly used in patients with neurofibromatosis type 2 (NF2) in whom tumour resection has damaged or destroyed the cochlear nerve, and in children with cochlear or cochlear-nerve malformations.
Step 2: Because the target is the cochlear nucleus complex, the electrode array must rest against the surface marking of that nucleus. The cochlear nucleus lies in the lateral recess of the fourth ventricle, so the implant is placed in the lateral recess of the 4th ventricle, usually during the same operation in which the vestibular schwannoma is removed. This makes option (b) correct.
Step 3: The distractors are sites for a cochlear implant or for nerve access, not for an ABI. The scala tympani (a) is where a cochlear implant electrode is threaded, which needs an intact cochlear nerve. The IAC (c) carries the cochlear nerve but is not the stimulation target for an ABI. The back of the ear (d) is only where the external receiver-stimulator hardware sits, not the active electrode.
Step 2: Because the target is the cochlear nucleus complex, the electrode array must rest against the surface marking of that nucleus. The cochlear nucleus lies in the lateral recess of the fourth ventricle, so the implant is placed in the lateral recess of the 4th ventricle, usually during the same operation in which the vestibular schwannoma is removed. This makes option (b) correct.
Step 3: The distractors are sites for a cochlear implant or for nerve access, not for an ABI. The scala tympani (a) is where a cochlear implant electrode is threaded, which needs an intact cochlear nerve. The IAC (c) carries the cochlear nerve but is not the stimulation target for an ABI. The back of the ear (d) is only where the external receiver-stimulator hardware sits, not the active electrode.
Was this answer helpful?
0
0
Top NEET PG ENT Questions
- A 30-year-old male presents with nonaxial proptosis of the left eye. The patient gives a history of a road traffic accident 15 years back. The CT image is given below. What is the most likely diagnosis?
- A 55-year-old patient comes with hoarseness of voice and difficulty swallowing. The patient was diagnosed with laryngeal carcinoma, and surgical management was done. The post-operative image of the patient is given below. Which of the following surgery was done on this patient?
- A female patient with hearing loss is examined and is found to be Rinne negative at 256 Hzand 512 Hz, while Rinne positive at 1024 Hz. What is the expected air conduction and bone conduction gap?
- Identify the structure marked in the image.
- The instrument shown in the image is not used for which of the following?
View More Questions
Top NEET PG Questions
- A patient hailing from Delhi presents with fever, arthralgia, and extensive petechial rash for 3 days. Lab investigations revealed a hemoglobin of 9 g/ dL, a white blood cell count of 9000 cells/mm3, a platelet count of 20000 cells/mm3, and a prolonged bleeding time. The clotting time was normal. What is the most likely diagnosis?
- Which of the following statements is true about Trichomonas vaginalis?
- A lady from West Rajasthan presented with an ulcer surrounded by erythema on the right leg. Microscopy of the biopsy from the edge of the ulcer showed organisms with dark staining nuclei and kinetoplast. What is the most likely causative agent?
- A child presents with a fever and a rash. Urine examination showed cells with owl's eye appearance. What is the most likely diagnosis?
- Infection with Clonorchis sinensis is associated with an increased risk of__?
View More Questions