Dynamics of endolymphatic hydrops according to magnetic resonance imaging of the inner ear after drainage of the endolymphatic sac

Background. Ménière's disease is a multifactorial disease characterized by recurrent dizziness, fluctuating hearing changes, congestion and noise in the ear. Despite the fact that spontaneous remission was registered in 71% of patients 8 years after the onset of the disease, a number of patients have a progressive course of the disease, in 10% of cases with bilateral lesions, debilitating episodes of dizziness, and hearing loss. Visualization of endolymphatic hydrops (EH) is performed using gadolinium-enhanced inner ear magnetic resonance imaging (MRI), by intravenous or intratympanic administration. Surgical treatment is recommended in case of ineffectiveness of drug therapy for 6–12 months; drainage of the endolymphatic sac (DEM) has been considered as an option in world practice since 1927.

Aim. To evaluate the change in EH after drainage of the DEM using intratympanic gadolinium-enhanced MRI of the inner ear.

Materials and methods. The study included 26 patients with Ménière's disease: 18 women and 8 men aged 20 to 71 years, with an average disease duration of 8.15 years (±7.04). The average duration and frequency of seizures before surgery were 4.29 hours (±3.29) and 6.08 times (±5.81) per month, respectively. All patients underwent DEM drainage, and the follow-up period was 1 year. An Intratympanic gadolinium-enhanced MRI of the inner ear was performed before and 6 months after surgery and evaluated in accordance with the criteria of Barani (2015).

Results. After EM drainage, a positive result of vertigo control was achieved in 17 (65.39%) patients. MRI examination at the preoperative stage revealed: pronounced vestibular hydrops, moderate cochlear EH – 14 (53.84%) patients, pronounced vestibular EH, pronounced cochlear EH – 8 (30.77%) patients, pronounced cochlear EH – 2 (7.69%) patients, moderate vestibular EH – 1 (3.85%) patient, severe vestibular EH – 1 (3.85%) patient. Six months after the operation, a control MRI examination with intratympanic gadolinium showed the following: without EH – 3 (11.54%) patients, decrease EH – 16 (61.54%) patients, no dynamics – 7 (26.92%) patients. The study showed a decrease in the degree of EH after DEM in 61.54% of cases according to intratympanic gadolinium-enhanced MRI of the inner ear.

Conclusion. Gadolinium-enhanced MRI data on endolymphatic hydrops changes in Ménière's disease patients, obtained before and after endolymphatic sac drainage, clearly demonstrate the effectiveness of this surgical treatment approach.