MRI patterns of global hypoxic-ischemic injury in adults

BACKGROUND AND PURPOSE

To assess MRI patterns and associated clinical outcome in adults with global hypoxic-ischemic injury.

MATERIALS AND METHODS

In order to identify the patients with evidence of global hypoxic-ischemic injury, we retrospectively searched our radiology information system for reports of brain MRI studies from 01/01/2004 to 12/31/2010, containing the keywords - "hypoxia", "hypoxic", "anoxia" and "anoxic". A board certified neuroradiologist visually inspected the corresponding MR images for the presence, location and extent (focal versus diffuse) of ischemic findings. Clinical data for these patients was collected from the electronic medical records, including mechanism of the hypoxic-ischemic injury, and clinical outcome was measured using modified Rankin Scale (mRS).

RESULTS

Review of radiology reports identified 151 cases, of which 64 patients remained after exclusion of normal studies ("no hypoxia" in the report), pediatric patients and patients with remote perinatal hypoxia. Five patients had relatively favorable clinical outcome (mRS of 1 to 3) and 59 had poor outcome (mRS of 4 to 6). Patterns associated with relatively favorable clinical outcome were: a) watershed pattern and b) basal ganglia without cortical involvement. Patterns associated with poor clinical outcome were: a) diffuse cortical and deep grey matter pattern, with and without perirolandic sparing; (b) medial occipital with perirolandic involvement; c) precentral gyrus involvement; d) diffuse white matter involvement; e) brainstem involvement; f) cerebellar involvement and g) hippocampal involvement.

CONCLUSION

The vast majority of patients with MRI patterns of hypoxic-anoxic injury have a poor clinical outcome, independently of the observed pattern, with the only relative exception being the watershed pattern and the basal ganglia pattern without cortical involvement.

Pituitary apoplexy: a rare cause of cerebral infarction. A case report

Pituitary apoplexy is usually the result of hemorrhagic infarction in pituitary adenoma. The clinical presentation of pituitary apoplexy varies widely and includes asymptomatic hemorrhage, classical pituitary apoplexy and even sudden death. Few cases of cerebral infarction associated with pituitary apoplexy have been reported in the literature. Pituitary apoplexy can cause narrowing of intracranial vessels by mechanical obstruction due to mass effect or by vasospasm resulting in cerebral ischemia. We report a case of pituitary apoplexy associated with cerebral infarction and the putative mechanisms.