What causes hearing loss in an healthy male?

Hello doctor,

My husband has had hearing loss for the past six years which has gotten worse with time. A few years back we took an MRI with and without contrast which showed nothing abnormal. A CT scan of the internal auditory canal also showed nothing abnormal. This week we took an MRI again and I have listed the report below.

1. Technique- Multiplanar MR imaging of the brain at 1.5 tesla.
2. Dedicated thin-section imaging through CP angles.
3. The IAC region is included.
4. Imaging was performed before and after contrast injection.
5. IV contrast - 20 ml injected, 0 ml discarded.
6. Contrast agent - Clariscan.

Findings:

1. Brain parenchyma: There are no significant parenchymal lesions. There is no evidence of acute intracranial hemorrhage, mass, or acute territorial infarction. There is no mass effect, midline shift, or extra-axial collection. The major intracranial flow voids are preserved.
2. IAC/CPA: There is no evident lesion associated with the CP angles or IACs. A note is made of sub-centimeter elongated focus of left cochlear enhancement, grossly stable from the prior study.
3. Ventricles and cisterns: The ventricles and cisterns are age appropriate in appearance. There is no hydrocephalus.
4. Skull, sinuses, and soft tissues: There is trace mucosal thickening within the bilateral ethmoid sinuses. There is no mastoid effusion.
5. Conclusion: Left cochlear enhancement which may reflect a small underlying schwannoma versus inflammation.

My husband has an appointment with his ENT specialist next week to discuss this result. I am concerned and confused. Could you shed some light on these results? Does he have an acoustic neuroma or is it just an inflammation?

Thank you.