MRI Imaging in Hypertensive Urgency with Unsteadiness
Yes, this patient should undergo MRI brain imaging despite the negative neurological exam, because unsteadiness with walking represents a neurological symptom that significantly increases the likelihood of intracranial pathology requiring immediate identification and management. 1
Clinical Context and Risk Stratification
The distinction between hypertensive urgency and emergency hinges on the presence of acute hypertension-mediated organ damage (HMOD), not the absolute blood pressure value. 1 In this case, the patient's unsteadiness with walking is a critical red flag that warrants further investigation:
Dizziness and unsteadiness are recognized manifestations of impaired cerebral autoregulation in the setting of severe hypertension and may indicate evolving hypertensive encephalopathy or other acute cerebrovascular pathology. 1, 2
Focal neurological symptoms—even subtle ones like unsteadiness—can signal stroke, hypertensive encephalopathy, or posterior reversible encephalopathy syndrome (PRES), all of which require immediate identification. 1, 3
The presence of neurological symptoms (including dizziness, lack of coordination, or unsteadiness) significantly increases the odds of finding an abnormality on neuroimaging, even when the formal neurological examination appears normal. 1
Why MRI is Indicated
MRI with FLAIR imaging is the preferred modality for evaluating suspected hypertensive encephalopathy and PRES, as it demonstrates characteristic white matter lesions in posterior brain regions that may not be visible on CT. 1
Key considerations supporting MRI:
CT may miss clinically significant lesions in hypertensive encephalopathy, particularly early white matter changes and subtle posterior circulation abnormalities. 1
The "negative neurological exam" does not exclude serious pathology when symptoms like unsteadiness are present—this represents a discordance that mandates imaging. 1
Hypertensive encephalopathy can present with subtle findings initially (lethargy, dizziness) before progressing to seizures, cortical blindness, and coma if untreated. 1, 3
Diagnostic Workup Algorithm
Before or concurrent with MRI, complete the following mandatory assessments: 1, 2
- Laboratory analysis: Hemoglobin, platelet count, creatinine, sodium, potassium, LDH, haptoglobin, quantitative urinalysis for protein, urine sediment
- ECG and fundoscopy to assess for other manifestations of acute HMOD
- Consider troponin if any chest symptoms present
Critical Pitfalls to Avoid
Do not dismiss unsteadiness as "benign" dizziness in the setting of hypertensive urgency—this symptom pattern has been specifically identified as increasing the likelihood of intracranial abnormalities. 1
Do not rely solely on the neurological examination—the absence of focal deficits on exam does not exclude hypertensive encephalopathy, PRES, or early stroke. 1
Do not delay imaging while attempting blood pressure reduction—identifying the underlying pathology guides appropriate BP targets and treatment intensity. 1
Management Implications
If MRI confirms hypertensive encephalopathy or PRES: 1
- Immediate blood pressure reduction is required (MAP reduction of 20-25% within 1 hour)
- Intravenous antihypertensive therapy in an intensive care setting
- The lesions are typically reversible with timely recognition and appropriate BP management 1
The combination of hypertensive urgency with neurological symptoms (unsteadiness) elevates this patient's risk profile and mandates neuroimaging to exclude life-threatening complications that would change immediate management. 1, 2