What is the purpose of this study? This observational study is being done to understand how cerebral small vessel disease (SVD) affects walking and balance. SVD is a common brain condition in older adults that damages small blood vessels. It can lead to problems with movement, thinking, and memory. The researchers want to find out how changes in brain activity and connectivity contribute to walking difficulties in people with SVD.

Why is this study important? Walking and balance problems increase the risk of falls and loss of independence. By studying brain activity during walking-related tasks, researchers hope to identify patterns that explain why these problems happen. This knowledge could help develop better rehabilitation methods in the future.

Who can participate? Adults over 50 years old with cerebral small vessel disease and gradual gait problems may be eligible. Healthy adults of similar age without neurological problems may also take part as control participants.

What will happen in this study?

Participants will:

Complete walking, balance, and cognitive tests such as the Timed Up and Go, Berg Balance Scale, and Montreal Cognitive Assessment.

Undergo brain imaging (MRI) to confirm the diagnosis and study brain structure and function.

Have an EEG recording while resting and while watching short videos showing walking and turning movements.

A smaller group will also undergo functional MRI (fMRI) while watching the same videos.

The MRI and EEG results will be analyzed to see how brain networks involved in movement and balance differ between patients and healthy adults.

How long will the study take? The study will take about two years to complete. Each participant's visit will last approximately two to three hours in total.

What are the possible benefits? There may be no direct benefit to participants. However, this study may help researchers understand how small vessel disease affects brain function related to walking, which may improve care for future patients.

Cerebral small vessel disease (SVD) is a common cause of walking and balance problems in older adults. These problems are often not explained by muscle weakness alone. They are believed to result from changes in how different parts of the brain communicate and coordinate movement.

This study will explore how brain network function is affected in people with SVD who experience gait difficulties. To do this, two safe and non-invasive techniques will be used:

Functional MRI (fMRI): to identify which brain areas become active when participants watch videos that simulate walking and turning.

Electroencephalography (EEG): to measure brain waves and the timing of brain activity while watching the same gait-related videos.

Participants will include 20 patients diagnosed with cerebral small vessel disease and gait problems, and 20 healthy adults of similar age without such problems.

All participants will undergo:

1. Clinical evaluation including walking, balance, and cognitive tests (Timed Up and Go, Berg Balance Scale, and Montreal Cognitive Assessment).
2. Brain MRI to confirm the diagnosis and exclude other causes.
3. Resting and task-based EEG recordings to assess brain connectivity.
4. Functional MRI for a subset of participants to study brain activity patterns related to gait imagery.

Researchers will compare the brain activation and connectivity between patients and healthy participants. They will also look for relationships between imaging findings and clinical test results.

By combining fMRI and EEG findings, this research aims to identify brain networks that are disrupted in people with SVD-related gait problems. Understanding these patterns may lead to better tools for early detection and more targeted rehabilitation approaches to improve walking and prevent falls.

All study procedures will be conducted at the Neurology Department, Ain Shams University Hospitals, Cairo, Egypt.

Inclusion Criteria:

• Age 50 years or older.

• Clinical and radiological diagnosis of cerebral small vessel disease (SVD), confirmed by MRI findings such as white matter hyperintensities, lacunes, or microbleeds.

• Fazekas score 2 or 3 on MRI.

• Presence of slowly progressive gait disturbance (e.g., slowness, imbalance, freezing) rather than acute stroke presentation.

  • Ability to give informed consent and cooperate with testing procedures.

Exclusion Criteria:

• Presence of other neurodegenerative disorders (e.g., Parkinson's disease, Alzheimer's disease).
• History of large vessel stroke or intracerebral hemorrhage.
• Contraindications to MRI (e.g., pacemaker, metallic implants, severe claustrophobia).
• Severe cognitive impairment that prevents participation (MoCA <10).
• Musculoskeletal or orthopedic causes of gait disturbance not related to neurological dysfunction.

Adults aged 50 years or older attending the Neurology outpatient clinics at Ain Shams University Hospitals, including patients with small vessel disease and gait impairment, and healthy controls.

The research team will decide after study completion whether de-identified participant data may be shared.

Time Frame To be determined after publication. Access Criteria Requests may be directed to the principal investigator and will require approval by the Faculty of Medicine, Ain Shams University.