From the Guidelines
Microhemorrhages seen on brain MRI are indicative of small vessel disease and require careful management to prevent further bleeding and cognitive decline, particularly in patients with hypertension, cerebral amyloid angiopathy, or those on anticoagulation therapy. These small bleeding spots in the brain appear as dark, round areas on certain MRI sequences, particularly gradient-echo or susceptibility-weighted imaging 1. The location of microhemorrhages can provide diagnostic clues, with those in deep brain regions suggesting hypertensive vasculopathy, while those in lobar (outer) regions may indicate amyloid angiopathy 1.
When microhemorrhages are detected, it's essential to control risk factors like high blood pressure, diabetes, and high cholesterol. Patients with numerous microhemorrhages may need careful consideration regarding anticoagulation therapy, as these medications could increase bleeding risk 1. Regular follow-up imaging may be recommended to monitor progression, and cognitive assessment might be appropriate as microhemorrhages can sometimes be associated with cognitive decline 1.
Key considerations in managing microhemorrhages include:
- Controlling hypertension and other vascular risk factors
- Careful consideration of anticoagulation therapy
- Regular follow-up imaging to monitor progression
- Cognitive assessment to evaluate for associated cognitive decline
- Interpretation of microhemorrhages in the context of the patient's complete clinical picture, including underlying conditions and medical history.
The clinical significance of microhemorrhages varies depending on number, location, and underlying conditions, emphasizing the need for individualized management and careful consideration of the patient's overall health status 1.
From the Research
Causes of Microhemorrhages
- Cerebral amyloid angiopathy and chronic systemic hypertension are the two most common causes of cerebral microhemorrhages 2
- Less common causes include diffuse axonal injury, cerebral embolism, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, multiple cavernous malformations, vasculitis, hemorrhagic micrometastasis, radiation vasculopathy, and Parry-Romberg syndrome 2
- Microhemorrhages have been associated with older age, hypertension, smoking, white matter disease, lacunar infarcts, previous ischemic stroke, or intracerebral hemorrhage (ICH) 3
Diagnosis and Significance
- Focal areas of signal loss on gradient-echo (GE) MRI imaging pathologically represent focal hemosiderin deposition associated with previous hemorrhagic events 3
- Cerebral microhemorrhages have been noted in healthy elderly, ischemic cerebrovascular disease, intracerebral hemorrhage (ICH), cerebral amyloid angiopathy (CAA), and in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy 3
- The presence of cerebral microbleeds (CMBs) increases the risk for stroke, dementia, and death 4
- The increasing number of CMBs is also associated with a higher risk of hemorrhagic complications with the long-term use of anticoagulants in atrial fibrillation and in patients requiring thrombolysis for acute stroke 4
Management and Treatment
- The presence of CMBs is not a contraindication for anticoagulation or thrombolysis 4
- Integrating cerebral microhemorrhages into patient management at the individual level will be crucial in the future 5
- Treatment decisions should be adjusted for each patient according to various genetic, biological, or imaging data, including the presence, location, and number of cerebral microhemorrhages 5
- Mixed-location cerebral hemorrhage/microbleeds are associated with a higher burden of vascular risk factors and a higher risk of ICH recurrence 6