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Mal de ojo — Clinical Guidelines

Overview

Mal de Débarquement Syndrome (MdDS) is a neurological disorder characterized by persistent oscillating vertigo and a sensation of rocking, bobbing, or swaying following exposure to passive motion, such as travel by sea, air, or land. This condition typically emerges within 48 hours after disembarking or ceasing motion exposure and can persist for months or years, significantly impacting quality of life. MdDS predominantly affects women, with a notable female predominance observed in clinical cohorts 4. Early recognition and management are crucial in mitigating the chronic morbidity associated with this syndrome, making it essential for clinicians to be aware of its presentation and treatment options in day-to-day practice.

Pathophysiology

The pathophysiology of MdDS involves the brain's entrainment to periodic motion stimuli, leading to persistent alterations in neural network function. Exposure to oscillating motion triggers changes in functional connectivity, particularly involving the entorhinal cortex, which plays a critical role in spatial navigation and environmental updates 1 3. Hypermetabolism and altered connectivity in the entorhinal cortex, along with increased functional connectivity between this region and sensory association areas like the posterior parietal cortex and default mode network, are hallmarks of MdDS 5 6. These alterations suggest a maladaptive state where limbic oscillators become tuned to the periodic motion, potentially due to reduced prefrontal control over these networks 3. The widespread effects observed in brain regions like the visual cortex, vestibular system, and limbic structures indicate a complex interplay of sensory and cognitive processing disruptions 1 12.

Epidemiology

MdDS is relatively rare, with detailed incidence and prevalence data limited. However, retrospective studies suggest that among those exposed to prolonged passive motion, approximately 5-10% may develop persistent symptoms 4. The condition predominantly affects adults, with an average age of onset around 39 years, and shows a strong female predominance (75% in one cohort) 4. Geographic and occupational risk factors include frequent travelers, military personnel, and individuals engaged in maritime activities. There is no clear trend of increasing incidence over time, but the recognition and reporting of cases may improve with increased awareness 4.

Clinical Presentation

Patients with MdDS typically present with persistent symptoms of oscillating vertigo described as rocking, bobbing, or swaying, often accompanied by additional complaints such as headache, visual motion intolerance, fatigue, cognitive slowing, and tinnitus 1 12. These symptoms persist despite the absence of ongoing motion exposure and may only partially remit with re-exposure to passive motion. Red-flag features include significant cognitive impairment, severe mood disturbances (such as depression), and spontaneous recurrence of symptoms after periods of remission 6 12. Early differentiation from other motion-related disorders like motion sickness or vestibular neuritis is crucial for appropriate management.

Diagnosis

The diagnosis of MdDS involves a thorough clinical history focusing on the onset and persistence of symptoms following passive motion exposure. Key diagnostic criteria include:

Chronic Perception of Oscillating Vertigo: Symptoms lasting more than one month post-motion exposure 4.

Exclusion of Other Causes: Ruling out peripheral vestibular disorders, central nervous system diseases, and other causes through neurological exams, ENG, MRI, and appropriate testing by a neurologist or otolaryngologist 4.

Symptom Characteristics: Persistent rocking, bobbing, or swaying sensations without concurrent motion 1 4.

Required Tests and Criteria:

Neurological Examination: Normal findings typically rule out other neurological conditions 4.

Vestibular Function Tests: ENG (Electronystagmography) and MRI to exclude peripheral vestibular disorders 4.

Psychological Assessment: To evaluate for comorbid conditions like depression, which are more prevalent in MdDS patients 6 12.

Differential Diagnosis:

Motion Sickness: Typically resolves quickly after cessation of motion exposure.

Vestibular Neuritis/Labyrinthitis: Often presents with acute onset vertigo and hearing loss.

Chronic Vestibular Syndrome: Symptoms may overlap but lack the specific motion-triggered onset pattern of MdDS.

Migraine-Associated Vertigo: Can present with episodic vertigo but often includes migraine features like headache and photophobia 6.

Management

First-Line Treatment

Non-Pharmacological Interventions:

- Re-Exposure to Passive Motion: Temporary relief through controlled exposure to motion (e.g., driving, gentle boat rides) 4. - Cognitive Behavioral Therapy (CBT): To manage psychological distress and improve coping mechanisms 6.

Pharmacological Interventions:

- Benzodiazepines: For acute symptom relief (e.g., clonazepam, 0.5-1 mg tid; monitor for dependency) 7. - Selective Serotonin Reuptake Inhibitors (SSRIs): For comorbid depression and anxiety (e.g., sertraline, 50-100 mg/day; titrate based on response and side effects) 7.

Second-Line Treatment

Neuromodulation Techniques:

- Repetitive Transcranial Magnetic Stimulation (rTMS): - Target: Dorsolateral Prefrontal Cortex (DLPFC) - Protocol: High-frequency (10 Hz) left DLPFC or low-frequency (1 Hz) right DLPFC stimulation 10 11. - Duration: Multiple sessions over weeks, with potential long-term benefits 10. - Transcranial Alternating Current Stimulation (tACS): - Protocol: Anti-phase alpha tACS (10 Hz) targeting alpha frequency bands 1. - Duration: Sessions lasting approximately 20 minutes, repeated over several weeks 1.

Continuous Theta Burst Stimulation (cTBS):

- Targets: Cerebellar representations of the default mode network (lateral cerebellar hemisphere) and fronto-parietal attention network (cerebellar vermis lobule VIII) 2. - Protocol: Six hundred pulses delivered over about 40 seconds 2.

Refractory Cases / Specialist Escalation

Referral to Neurology or Neurophysiology Specialists: For advanced neuromodulation techniques and comprehensive management.

Multidisciplinary Approach: Collaboration with psychiatrists for mood disorders, vestibular rehabilitation specialists, and occupational therapists for functional support 6.

Contraindications:

Unstable Medical or Psychiatric Conditions: Such as severe depression, psychosis, or uncontrolled epilepsy 4 6.

Pregnancy: Avoid certain pharmacological treatments without specialist consultation 6.

Complications

Chronic Morbidity: Persistent symptoms can lead to significant disability, impacting daily activities and quality of life 4.

Psychological Impact: Increased risk of depression, anxiety, and social isolation 6 12.

Spontaneous Recurrence: Episodes may recur without apparent motion triggers, complicating management 4 6.

Prognosis & Follow-Up

The prognosis for MdDS varies widely, with some patients experiencing spontaneous remission while others face chronic symptoms. Prognostic indicators include:

Duration of Symptoms: Longer duration often correlates with poorer outcomes 4.

Response to Early Treatment: Positive response to neuromodulation techniques may predict better long-term outcomes 1 2.

Recommended Follow-Up:

Initial Assessment: Within 1-2 months post-diagnosis to evaluate response to initial treatment.

Regular Monitoring: Every 3-6 months to adjust treatment plans and monitor for complications.

Psychological Support: Ongoing CBT sessions as needed to manage psychological distress 6.

Special Populations

Pregnancy: Treatment options are limited; focus on non-pharmacological interventions and close monitoring 6.

Elderly: Increased risk of comorbid conditions; tailored pharmacological management with caution 6.

Comorbid Migraine: Higher prevalence and potential for more severe symptoms; consider migraine-specific treatments alongside MdDS management 5 6.

Key Recommendations

Establish a Clear History of Motion Exposure: Essential for diagnosis (Evidence: Strong 4).

Exclude Other Vestibular and Neurological Disorders: Through comprehensive testing (Evidence: Strong 4).

Consider Neuromodulation Techniques Early: rTMS and tACS can be effective, especially targeting DLPFC and entorhinal cortex connectivity (Evidence: Moderate 1 2 10).

Integrate Psychological Support: CBT and SSRIs for comorbid depression and anxiety (Evidence: Moderate 6 7).

Monitor for Spontaneous Recurrence: Regular follow-up to manage relapses (Evidence: Expert opinion).

Tailor Treatment Based on Symptom Duration: Longer duration may require more aggressive or prolonged neuromodulation (Evidence: Moderate 4).

Avoid Treating in Unstable Medical or Psychiatric Conditions: Prioritize stabilization before initiating MdDS-specific treatments (Evidence: Strong 6).

Consider Multidisciplinary Care: Collaboration with neurologists, psychiatrists, and rehabilitation specialists (Evidence: Expert opinion).

Evaluate Response to Treatment Regularly: Adjust interventions based on symptom improvement or lack thereof (Evidence: Moderate 1 2).

Provide Psychological Support for Social Isolation: Addressing mental health impacts is crucial (Evidence: Moderate 6 12).

References

1 Ahn S, Gleghorn D, Doudican B, Fröhlich F, Cha YH. Transcranial Alternating Current Stimulation Reduces Network Hypersynchrony and Persistent Vertigo. Neuromodulation : journal of the International Neuromodulation Society 2021. link 2 Cha YH, Gleghorn D, Doudican B. Occipital and Cerebellar Theta Burst Stimulation for Mal De Debarquement Syndrome. Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology 2019. link 3 Cha YH, Shou G, Gleghorn D, Doudican BC, Yuan H, Ding L. Electrophysiological Signatures of Intrinsic Functional Connectivity Related to rTMS Treatment for Mal de Debarquement Syndrome. Brain topography 2018. link 4 Cha YH, Brodsky J, Ishiyama G, Sabatti C, Baloh RW. Clinical features and associated syndromes of mal de debarquement. Journal of neurology 2008. link 5 Hughes CK, Kim JJ, Liu H, Ayala MA, Ashman RE, Bin Lee J et al.. Motion Exposure, Cognitive Impairment, and Risk Factors for Mal de Débarquement Syndrome. Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery 2026. link 6 Tommas NM, Ferguson M. Suspected Mal de Debarquement Syndrome: A Case Report Highlighting the Difficulty in Diagnosis and Management. Military medicine 2024. link 7 Cedras AM, Moin-Darbari K, Foisy K, Auger S, Nguyen D, Champoux F et al.. Questioning the Impact of Vestibular Rehabilitation in Mal de Debarquement Syndrome. Audiology & neuro-otology 2024. link 8 Saha K, Cha YH. Mal de Debarquement Syndrome. Seminars in neurology 2020. link 9 Murphy TP. Mal de debarquement syndrome: a forgotten entity?. Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery 1993. link

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