What is the recommended management for a patient with chronic small vessel ischemic changes, generalized volume loss, and a slight interval enlargement of an infratentorial subdural hygroma, presenting with symptoms of dizziness, headache, and tinnitus?

Management of Infratentorial Subdural Hygroma with Chronic Small Vessel Ischemic Changes

Conservative management with close monitoring is recommended for this patient with an infratentorial subdural hygroma showing slight interval enlargement, given the absence of acute intracranial abnormality or significant mass effect.

Clinical Assessment of the MRI Findings

The MRI findings in this patient reveal several key issues:

1. Infratentorial subdural hygroma:

   • Located along the left cerebellar hemisphere
   • Increased from 9mm to 13mm since 2016
   • Causing slight medial deviation of the left cerebellar hemisphere
   • No pathologic enhancement

2. Chronic small vessel ischemic changes:

   • Partially confluent foci of T2 signal hyperintensities in white matter
   • Increased compared to prior imaging
   • Consistent with chronic small vessel disease

3. Generalized volume loss:

   • Mild proportional enlargement of ventricles and CSF spaces
   • Commensurate with age

Management Approach

For the Infratentorial Subdural Hygroma

1. Observation is appropriate since:

   • The hygroma shows only slight interval enlargement
   • There is minimal mass effect (only slight medial deviation of cerebellum)
   • No pathologic enhancement is present
   • No acute intracranial abnormality is identified

2. Follow-up imaging:

   • Repeat MRI in 3-6 months to assess stability or progression
   • Earlier imaging if symptoms worsen

3. Surgical intervention is not indicated at this time as:

   • The European Stroke Organisation guidelines note insufficient evidence from RCTs for surgical evacuation of infratentorial hemorrhage/fluid collections without significant mass effect 1
   • Current guidelines do not support surgical intervention for asymptomatic or minimally symptomatic hygromas without significant mass effect 1

For Chronic Small Vessel Ischemic Changes

1. Vascular risk factor management:

   • Optimize blood pressure control
   • Manage diabetes if present
   • Lipid management
   • Smoking cessation if applicable
   • Regular physical activity

2. Consider cognitive assessment:

   • Patients with small vessel disease have increased risk of cognitive impairment 2
   • More than half of patients with small vessel disease may fulfill criteria for mild cognitive impairment 2

Symptom Management

For the patient's presenting symptoms of dizziness, headache, and tinnitus:

1. Headache management:

   • First-line: acetaminophen and/or NSAIDs 1
   • Avoid opioids for long-term management
   • Consider if symptoms are positional (worse when upright, better when lying down), which could suggest intracranial hypotension

2. Dizziness management:

   • Vestibular rehabilitation exercises if vertigo is present
   • Rule out orthostatic hypotension
   • Consider vestibular suppressants for symptomatic relief

3. Tinnitus management:

   • Consider audiology evaluation
   • Sound therapy or masking devices
   • Cognitive behavioral therapy if significantly bothersome

Monitoring and Follow-up

1. Clinical monitoring:

   • Regular neurological examinations
   • Monitor for new or worsening symptoms:
     • Headache pattern changes
     • Balance difficulties
     • Visual changes
     • Cognitive changes
     • Focal neurological deficits

2. Warning signs requiring urgent evaluation:

   • Sudden severe headache
   • Rapid neurological deterioration
   • New focal deficits
   • Altered level of consciousness

3. Imaging follow-up:

   • MRI with contrast in 3-6 months
   • Include blood-sensitive sequences to detect potential superficial siderosis 1

Special Considerations

1. Intracranial hypotension:

   • Consider this diagnosis if headaches are orthostatic
   • The subdural hygroma may be related to CSF volume depletion
   • If suspected, dedicated spine imaging may be warranted to identify CSF leak 1

2. Cerebral venous thrombosis:

   • Consider CT or MR venography if there is sudden change in headache pattern 1
   • Ipsilateral dural thickening can sometimes be associated with cortical vein thrombosis 1

3. Transformation risk:

   • Subdural hygromas can potentially transform into chronic subdural hematomas 3, 4
   • This risk underscores the importance of follow-up imaging

Conclusion

This patient's imaging findings of a slightly enlarged infratentorial subdural hygroma with chronic small vessel ischemic changes warrant conservative management with close clinical and radiological monitoring. The absence of acute abnormalities, significant mass effect, or pathologic enhancement supports this approach. Management should focus on symptom control, vascular risk factor optimization, and vigilant monitoring for any clinical deterioration or imaging changes that might necessitate intervention.