Spontaneous intracerebral hemorrhage MRI
Although CT remains important in the acute setting, MR imaging has proved invaluable for diagnosis and characterization of intracranial hemorrhage diagnosis.
Usually not the procedure of choice for initial study. Disadvantages compared to CT scan:
1. does not show blood well within the first few hours (gradient echo and SWI are the best sequences)
2. difficult to ventilate or access patient during the study
3. slower and more expensive, not available in as many E/Rs
4. contraindications e.g. claustrophobia in awake patients, as well as others that may not be known at the time of initial evaluation (e.g. shrapnel in the eye, non-MRI compatible pacemaker or spi- nal cord stimulator…)
May be useful later, e.g. to help diagnose cerebral amyloid angiopathy (CAA).
The appearance of ICH on MRI is very complicated. It is highly dependent on the age of the clot
MRI and MRA studies are routinely obtained to identify the etiology of intracerebral hemorrhage (ICH). The diagnostic yield of MRI/MRA in the setting of an acute ICH, however, remains unclear.
Chalouhi et al. goal was to determine the utility of early MRI/MRA in detecting underlying structural lesions in ICH and to identify patients in whom additional imaging during hospitalization could safely be foregone.
The authors reviewed data obtained in 400 patients with spontaneous ICH diagnosed on noncontrast head CT scans who underwent MRI/MRA between 2015 and 2017 at their institution. MRI/MRA studies were reviewed to identify underlying lesions, such as arteriovenous malformations, aneurysms, cavernous malformations, arteriovenous fistulas, tumors, sinus thrombosis, moyamoya disease, and abscesses.RESULTSThe median patient age was 65 ± 15.8 years. Hypertension was the most common (72%) comorbidity. Structural abnormalities were detected on MRI/MRA in 12.5% of patients. Structural lesions were seen in 5.7% of patients with basal ganglia/thalamic ICH, 14.1% of those with lobar ICH, 20.4% of those with cerebellar ICH, and 27.8% of those with brainstem ICH. Notably, the diagnostic yield of MRI/MRA was 0% in patients > 65 years with a basal ganglia/thalamic hemorrhage and 0% in those > 85 years with any ICH location, whereas it was 37% in patients < 50 years and 23% in those < 65 years. Multivariate analysis showed that decreasing age, absence of hypertension, and non-basal ganglia/thalamic location were predictors of finding an underlying lesion.
The yield of MRI/MRA in ICH is highly variable, depending on patient age and hemorrhage location. The findings of this study do not support obtaining early MRI/MRA studies in patients ≥ 65 years with basal ganglia/thalamic ICH or in any ICH patients ≥ 85 years. In all other situations, early MRI/MRA remains valuable in ruling out underlying lesions 1).