Is dehydration test using isosorbide useful in Meniere's disease?

Area of Science:

• Otolaryngology
• Neuroscience
• Diagnostic Medicine

Background:

• Meniere's disease (MD) is characterized by endolymphatic hydrops.
• Accurate diagnosis of MD is crucial for effective management.
• Current diagnostic methods may have limitations in sensitivity.

Purpose of the Study:

• To evaluate the diagnostic utility of an oral isosorbide dehydration test in patients with Meniere's disease.
• To assess the safety and tolerability of the isosorbide dehydration test.
• To determine if the dehydration test improves the sensitivity of electrocochleography (ECoG).

Main Methods:

• A prospective study involving 32 patients diagnosed with definite Meniere's disease.
• Administration of 120 mL oral isosorbide followed by repeat audiometric testing after 3 hours.
• Electrocochleography (ECoG) with a summating potential/action potential (SP/AP) ratio threshold of ≥0.4 for abnormality.

Main Results:

• The isosorbide dehydration test was positive in 31.3% of patients and well-tolerated without serious side effects.
• Abnormal ECoG findings were observed in 43.8% of patients.
• Combined ECoG and dehydration test detected endolymphatic hydrops in 65.6% of patients, with a higher positive rate in those with low-frequency hearing loss.

Conclusions:

• The isosorbide dehydration test is a safe and effective tool for detecting endolymphatic hydrops in Meniere's disease.
• The test enhances the diagnostic sensitivity of ECoG, especially in patients with significant low-frequency hearing loss.
• Isosorbide dehydration testing offers a valuable adjunct for diagnosing Meniere's disease.