Imaging of Neurologic Conditions During Pregnancy and the Perinatal Period

Posterior reversible encephalopathy syndrome induced by intracranial hypotension in a postpartum patient

Objective: A number of hormonal, physiologic, immunologic, and hemodynamic changes can cause a series of central nervous system-related problems in pregnant and postpartum women. Posterior reversible encephalopathy syndrome (PRES) is commonly seen in these conditions. However, PRES during pregnancy and the postpartum period are not always due to pregnancy.Methods: We describe a patient who presented with headache followed by an epileptic seizure after cesarean section and whose computed tomography (CT) showed bilateral low-density lesions in the frontal lobe. To explore the pathogenesis, we further examined the patient with brain magnetic resonance imaging (MRI) and lumbar puncture.Results: Brain MRI revealed vasogenic edema in the frontal lobe and temporal-occipital regions of both hemispheres. MRI of the brain with contrast showed diffuse enhancement of the supratentorial dura mater and decreased of bilateral lateral ventricles. There was no abnormality in brain magnetic resonance angiography and magnetic resonance venography. Bloody cerebrospinal fluid flowed very slowly during lumbar puncture.Conclusion: These findings suggest that, although rare, intracranial hypotension in postpartum patients may be a cause of PRES.

Imaging of neurovascular emergencies in pregnancy and puerperium

Acute neurovascular events, though rare, can complicate pregnancy and postpartum period. It is important to be aware of these clinical conditions for reducing maternal and fetal morbidity and mortality. In this review, we present a few important neurovascular emergencies and their imaging manifestations by various imaging modalities-computed tomography (CT), magnetic resonance imaging (MRI), and digital subtraction angiography (DSA)-which presented at our institution in the peripartum period.

Microcirculation Approach in HELLP Syndrome Complicated by Posterior Reversible Encephalopathy Syndrome and Massive Hepatic Infarction

HELLP syndrome is a complication of severe forms of preeclampsia and occurs mainly in the third trimester of pregnancy. In extreme cases, it may evolve unfavorably and substantially increase maternal mortality. We present the case of an 18-year-old pregnant woman who was admitted to our emergency service in her 31st week, presenting with headache, visual disturbances, and epigastralgia, with progression to a severe condition of HELLP syndrome followed by posterior reversible encephalopathy syndrome (PRES) and hepatic infarction. We highlight the approach taken towards this patient and the case management, in which, in addition to the imaging examinations routinely available, we also used the sidestream dark field (SDF) technique to evaluate the systemic microcirculation.

Imaging in the evaluation of headache

When deciding to perform imaging for headache, it is important to consider many factors including the pretest probability, prevalence of diseases, sensitivity of imaging, and implications for treatment. For the first presentation of a headache or a change in headache pattern, if the characteristics do not perfectly fit a primary headache type, imaging may be indicated according to the ICHD-2 criteria to exclude a secondary cause before a primary headache is diagnosed. The value of negative imaging should not be underestimated in the cost-benefit analysis, which often only takes into account number needed to treat or likelihood of finding a significant treatable abnormality. One study has shown that some groups of patients are less likely to overuse other parts of the health care system after negative neuroimaging. Further studies with stronger methodologies, finer differentiation of acute and chronic headache presentations, more advanced imaging technology, among other factors, can improve decision making on when to use imaging and assess the impact of imaging on patient satisfaction and quality of life. In addition, functional MRI, MRS, and voxel-based morphometry MRI are only some of the neuroimaging techniques currently used in research to further understand the pathophysiology and mechanisms of headache. In conclusion, although most headaches are a primary headache disorder with a benign course, imaging is an important part of the diagnostic evaluation to exclude the presence of a secondary cause of headache that could cause fatal results or severe neurologic morbidity. In headache patients without focal neurologic examination abnormalities, the yield of neuroimaging for significant intracranial findings is generally low. However, specific subgroups of headache patients and headache presentations can have much higher rates of significant intracranial abnormalities.