MR imaging findings of medulla oblongata involvement in posterior reversible encephalopathy syndrome secondary to hypertension

Posterior reversible encephalopathy syndrome coexists with acute cerebral infarction: challenges of blood pressure management

Hypertension is the most common cause of posterior reversible encephalopathy syndrome (PRES) and acute cerebral infarction. Due to the lack of randomized controlled clinical trials (RCTs), early antihypertensive methods are diverse, even contradictory. So far, there is no consensus on the method of blood pressure (BP) management when the 2 diseases coexist. Generally, antihypertensive therapy should be initiated quickly in the acute phase of PRES, as most patients have elevated BP. However, various factors must be considered before the administration of early antihypertensive therapy in acute cerebral infarction. The coexistence of PRES and acute cerebral infarction is uncommon clinically, and more complicated subsequent BP management. This article reports a case of PRES coexisting with acute lacunar cerebral infarction, which was caused by hypertension. We have analyzed and summarized the antihypertensive principles in PRES and different phases of acute cerebral ischemic injury. We assert that when PRES and acute cerebral infarction coexist, the antihypertensive treatment should be individualized, and careful consideration should be given to the various influencing factors.

Detecting the Uncommon Imaging Manifestations of Posterior Reversible Encephalopathy Syndrome (PRES) in Adults: a Comprehensive Illustrated Guide for the Trainee Radiologist

Posterior reversible encephalopathy syndrome (PRES) has traditionally been described as a reversible leukoencephalopathy with a distinct pattern of posteriorly distributed vasogenic oedema involving the subcortical regions of parietal and occipital lobes. PRES commonly occurs in the setting of hypertensive emergencies, pre-eclampsia/eclampsia, impaired renal function, and immunosuppressive therapy. The various clinical presentations of PRES include encephalopathy, seizures, headache, visual, and focal neurological deficits. As knowledge of this entity grows, the range of clinical, and radiological features is seen to be much broader than originally described. The brain oedema may not always be posteriorly distributed and the syndrome may not be uniformly reversible. Of special note are some uncommon imaging features (unilateral cerebral involvement, and isolated posterior fossa involvement) and also some uncommon complications (haemorrhage, cytotoxic oedema, and vasoconstriction). These red herrings may lead to potential diagnostic challenges and pitfalls especially for trainee radiologists, who often read these scans in an emergency setting. Early and accurate diagnosis is crucial for prompt optimum management, thereby avoiding residual morbidity. This review article focusses on the atypical radiological features of PRES in adults with extensive case-based imaging examples. A brief description of the pathophysiology, clinical, and classic radiological features of PRES has also been included. A tabulated summary of potential mimics with diagnostic pearls is provided to highlight pertinent take home points and to serve as an easy guide for day-to-day clinical practice.

[Clinical and imaging course of posterior reversible encephalopathy syndrome in a patient with endocarditis and arterial hypertension]

Posterior reversible encephalopathy (PRES) is a clinical syndrome characterized by headaches, seizures, cortical blindness, and altered mental status up to coma and by a radiological syndrome defined by edematous alteration on Magnetic Resonance Imaging (MRI)-Scans of the white matter. In the following, we present the case of a 73 years old post-operative patient with PRES in the context of hypertension and endocarditis with E. coli. The initial presentation included a series of seizures, sopor, and cortical blindness. In MRI-Scans a marked cerebral edema could be identified. After successful treatment of underlying conditions, the patient has made a good recovery. However, homonymous hemianopsia towards right due to laminar necrosis in the left occipital lobe remained as a residuum.

Clinical features, outcomes and risk factors for posterior reversible encephalopathy syndrome in systemic lupus erythematosus: a case-control study

OBJECTIVE

The objective of this paper is to investigate the clinical features, outcomes, and risk factors for posterior reversible encephalopathy syndrome (PRES) in systemic lupus erythematosus (SLE).

METHODS

From 2011 to October 2017, SLE patients with PRES were identified from the First Affiliated Hospital of Zhengzhou University, China. Patients presenting with neuropsychiatric lupus hospitalized in the same period were included as controls. Additionally, survival status was acquired via telephone follow-up in March 2018.

RESULTS

Thirty episodes of PRES were identified in 29 SLE patients from a total of 7059 SLE patients (prevalence 0.43%). Patients with PRES had a younger age at onset than controls, with seizures more commonly the initial clinical manifestation (80.00% vs 42.37%, p = 0.001). Multiple logistic regression yet again confirmed several known risk factors, including younger age (odds ratio (OR) 1.15 (95% confidence interval (CI) 1.13-1.16)), nephritis (OR 20.74 (18.10-23.75)), history of hypertension (OR 1.17 (1.05-1.31)), SLE Disease Activity Index without neurologic symptoms (SLEDAI-N) score >12 (OR 1.14 (1.11-1.18)) and eclampsia (OR 9.38 (7.84-11.23)). Furthermore, we identified two novel independent risk factors for PRES in SLE: white blood cells >9 × 10⁹/l (OR 2.33 (2.05-2.64)) and heart failure (OR 2.10 (1.18-2.42)). At follow-up, SLE patients with PRES had higher mortality than controls (30.77% vs 8.33%, respectively, p = 0.012).

CONCLUSIONS

PRES may be a reversible neurological deficit in patients with SLE other than neuropsychiatric lupus. Our results indicate two new risk factors for PRES and that PRES is associated with a higher mortality rate.

Isolated brainstem involvement in posterior reversible encephalopathy syndrome: a case report and review of the literature

Posterior reversible encephalopathy syndrome (PRES) is a clinical-radiological syndrome, reversible vasogenic edema predominantly within parieto-occipital regions. However, isolated brainstem involvement in PRES has been rarely reported, little is known about its clinical manifestations, radiological features and outcomes. We reported a case with PRES with only brainstem involvement and performed a systematic review of published cases. Twenty-four cases, together with our case, were included in the analysis. Mean age was 43 years and 63% were males. Hypertension (50%), nephropathy (25%) and chemotherapy (21%) were the major risk factors. All patients except two had acute hypertension and 50% of patients had renal dysfunction at onset. The most common symptoms were altered consciousness (46%) and headache (46%), Seizure was only presented in 21% of patients. All patients except two were treated with antihypertension. Most patients recovered to their neurological baseline. Clinicians should recognize this unique variant finding in PRES. which always affects males with severe hypertension, especially combined with renal dysfunction. Antihypertensive treatment is the most widely used therapy. Outcome is usually well.

Influential factors and clinical significance of an atypical presentation of posterior reversible encephalopathy syndrome in patients with eclampsia

BACKGROUND AND PURPOSE

Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiologic entity for which eclampsia is one of the most common predisposing conditions. Despite the imaging changes typically reported, the predisposing factors and clinical implications of atypical presentations have yet to be fully clarified.

METHODS

A total of 56 patients with PRES were selected for study. Demographic, clinical, and laboratory data were analyzed, focusing on atypical presentations of PRES. Multiple logistic regression was applied to identify factors impacting such atypical presentations, and functional outcomes were assessed upon patient discharge.

RESULTS

Overall, 22 of the 56 patients (39.3%) displayed features of atypical PRES. By multiple logistic regression, headache (OR = 5.39; 95% CI, 1.24-23.51; p = 0.025) and frequent convulsions (OR = 4.41; 95% CI, 1.09-17.91; p = 0.038) proved to be independent factors associated with atypical PRES. Ultimately, outcomes of 18 patients were gauged as poor, based on the modified Rankin Scale (mRS). Logistic regression indicated that visual disturbances (OR = 9.02; 95% CI, 1.37-59.35; p = 0.02), frequent convulsions (OR = 9.47; 95% CI, 1.67-53.63; p = 0.01), and restricted diffusion on imaging (OR = 11.96; 95% CI, 1.76-81.11; p = 0.01) were independently associated with poor outcomes in patients with eclampsia-related PRES.

CONCLUSION

Headache and frequent convulsions are independently associated with atypical presentations of PRES. If present, restricted diffusion may help in predicting poor outcomes of such patients upon discharge.

Posterior Reversible Encephalopathy Syndrome With Isolated Involving Infratentorial Structures

Typical neuroimaging findings of posterior reversible encephalopathy syndrome include symmetrical white matter edema in subcortical white matter of bilateral occipital and parietal lobes, although variations do occur and more and more attention is being focused upon disease of infratentorial-isolated involved posterior reversible encephalopathy syndrome. In this article, we described 1 case of posterior reversible encephalopathy syndrome with isolated infratentorial brain involvement and reviewed the literature to identify an additional 36 cases in the PubMed database. We used various search terms, such as "brainstem/cerebella/spinal posterior reversible encephalopathy syndrome," "brainstem/cerebella/spinal reversible posterior leukoencephalopathy syndrome," "brainstem/cerebella/spinal hypertensive encephalopathy," "infratentorial posterior reversible encephalopathy syndrome," and "posterior reversible encephalopathy syndrome variant." Then, we systematically analyzed the clinical and imaging characteristics of the 37 cases and found that posterior reversible encephalopathy syndrome with isolated involving infratentorial structures predominantly affect male patients compared with typical posterior reversible encephalopathy syndrome. The presence of extremely high blood pressure at onset is essential to the development of infratentorial-isolated involved posterior reversible encephalopathy syndrome. A relatively high rate of hydrocephalus and spinal cord involvement can be a distinctive feature of this kind of variant. Symptoms and outcomes are basically similar to typical posterior reversible encephalopathy syndrome.

Reversible brain lesion following growth hormone replacement therapy in an adolescent

A 12.6-year-old girl presented with a 2-month history of headache, recurrent vomiting and 5 kg weight loss. She had been receiving recombinant human growth hormone (rhGH) replacement therapy at a dose of 0.035 mg/kg for the past 10 months, due to short stature. Investigations before initiating rhGH, including brain MRI, had been normal. Physical examination revealed a nystagmus and a mildly elevated arterial blood pressure. Brain MRI revealed a lesion in the posterior aspect of the medulla oblongata, adjacent to the foramen of Magendie. rhGH therapy was discontinued, followed by a gradual resolution of the symptoms. At follow-up 3 months later, she was asymptomatic and physical examination was unremarkable. A subsequent repeat brain MRI showed complete resolution of the lesion, supporting the diagnosis of a variant of reversible posterior leucoencephalopathy syndrome. This is the first case report of a reversible brain lesion linked to rhGH replacement therapy.

Magnetic Resonance Imaging of Cerebral Malaria Patients Reveals Distinct Pathogenetic Processes in Different Parts of the Brain

The pathophysiology and molecular mechanisms underlying cerebral malaria (CM) are still poorly understood. Recent neuroimaging studies demonstrated that brain swelling is a common feature in CM and a major contributor to death in pediatric patients. Consequently, determining the precise mechanisms responsible for this swelling could open new adjunct therapeutic avenues in CM patients. Using an MRI scanner with a higher resolution than the ones used in previous reports, we identified two distinct origins of brain swelling in both adult and pediatric patients from India, occurring in distinct parts of the brain. Our results support the hypothesis that both endothelial dysfunction and microvascular obstruction by Plasmodium falciparum-infected erythrocytes make independent contributions to the pathogenesis of CM, providing opportunities for novel therapeutic interventions.

The mechanisms underlying the rapidly reversible brain swelling described in patients with cerebral malaria (CM) are unknown. Using a 1.5-Tesla (T) magnetic resonance imaging (MRI) scanner, we undertook an observational study in Rourkela, India, of 11 Indian patients hospitalized with CM and increased brain volume. Among the 11 cases, there were 5 adults and 6 children. All patients had reduced consciousness and various degrees of cortical swelling at baseline. The latter was predominately posterior in distribution. The findings on diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps were consistent with vasogenic edema in all cases. Reversibility after 48 to 72 h was observed in >90% of cases. DWI/ADC mismatch suggested the additional presence of cytotoxic edema in the basal nuclei of 5 patients; all of these had perfusion parameters consistent with vascular engorgement and not with ischemic infarcts. Our results suggest that an impairment of the blood-brain barrier is responsible for the brain swelling in CM. In 5 cases, vasogenic edema occurred in conjunction with changes in the basal nuclei consistent with venous congestion, likely to be caused by the sequestration of Plasmodium falciparum-infected erythrocytes. While both mechanisms have been individually postulated to play an important role in the development of CM, this is the first demonstration of their concurrent involvement in different parts of the brain. The clinical and radiological characteristics observed in the majority of our patients are consistent with posterior reversible encephalopathy syndrome (PRES), and we show for the first time a high frequency of PRES in the context of CM.

IMPORTANCE The pathophysiology and molecular mechanisms underlying cerebral malaria (CM) are still poorly understood. Recent neuroimaging studies demonstrated that brain swelling is a common feature in CM and a major contributor to death in pediatric patients. Consequently, determining the precise mechanisms responsible for this swelling could open new adjunct therapeutic avenues in CM patients. Using an MRI scanner with a higher resolution than the ones used in previous reports, we identified two distinct origins of brain swelling in both adult and pediatric patients from India, occurring in distinct parts of the brain. Our results support the hypothesis that both endothelial dysfunction and microvascular obstruction by Plasmodium falciparum-infected erythrocytes make independent contributions to the pathogenesis of CM, providing opportunities for novel therapeutic interventions.

Posterior Reversible Encephalopathy Syndrome With Spinal Cord Involvement in Children

We characterized a cohort of patients with posterior reversible encephalopathy syndrome with spinal cord involvement. We encountered 2 children and identified an additional 19 patients from the internet databases. Of the 21 patients analyzed, 8 were children. The mean peak systolic blood pressure in adults was significantly higher than in children (221.8 ± 14.3 vs 191.4 ± 31.3 mm Hg; P < .01). Regardless of age, the most common clinical symptom was headache (90%) and the least common clinical symptom was seizures (28%). Atypical neuroimaging was more common in children (63%) than in adults (8%). Abnormal cerebrospinal fluid results were frequently found in children (83%). All children recovered uneventfully, but 3 adults had sequelae. A broader clinicoradiologic spectrum makes the diagnosis of children more complex than in adults. Awareness of the atypical features with a meticulous management of hypertension is imperative to avoid unnecessary invasive workups and to achieve an uneventful recovery.

Posterior reversible encephalopathy syndrome with involvement of the cervical cord and medulla: a case report

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state, which is associated with symmetrical subcortical areas of vasogenic oedema that are preferentially parieto-occipital, and it typically resolves within a few weeks after appropriate treatment, We hereby report a case of a female with adrenal tumour presenting with PRES, who was featured by a very rare neuroimaging manifestation, the involvement of cervical cord and medulla.

Risk of subsequent dementia in patients with hypertensive encephalopathy: a nationwide population-based study in Taiwan

BACKGROUND/AIMS

We investigated the association of hypertensive encephalopathy (HE) with subsequent dementia.

METHODS

Using universal insurance claims data, we identified a study cohort of 5,504 participants with HE newly diagnosed between 1997 and 2010 and a comparison cohort of 22,016 healthy participants. Incidence and risks of dementia were estimated for both cohorts until the end of 2010.

RESULTS

The dementia incidence was 1.45-fold [95% confidence interval (CI) = 1.27-1.66] higher in the study cohort than in the comparison cohort, with an adjusted hazard ratio (HR) of 1.38 (95% CI = 1.19-1.59) for the study cohort. The risk was higher for males than for females and elderly patients. With an incidence of 13.4 per 1,000 person-years, the HR of dementia increased to 2.09 (95% CI = 1.18-3.71) for the HE patients with the comorbidities of head injury and diabetes compared to those without HE and comorbidities. The risk of developing dementia declined with the follow-up time.

CONCLUSION

Hypertensive patients with HE displayed a significantly higher risk for dementia than those without HE. The risk increased further in those with the comorbidities of head injury and diabetes. Physicians should be aware of the link between HE and dementia when assessing patients with HE.

Central-variant posterior reversible encephalopathy syndrome: brainstem or basal ganglia involvement lacking cortical or subcortical cerebral edema

OBJECTIVE

Although posterior reversible encephalopathy syndrome (PRES) typically involves cortical or subcortical edema of the cerebrum, only individual cases have been described of a variant involving the central brainstem and basal ganglia and lacking cortical and subcortical edema. We evaluated FLAIR and T2-weighted images of 124 patients with confirmed PRES to determine the incidence of this uncommon variant, which we refer to as the "central variant"; to determine which structures are involved in this variant; and to determine the associated causes.

CONCLUSION

We found that five of the 124 patients (4%) with PRES had MR findings consistent with the central variant-that is, either brainstem or basal ganglia involvement and a lack of cortical or subcortical edema of the cerebrum. The thalami were involved in all five PRES patients with MR findings consistent with the central variant, but there was variable involvement of the posterior limb of the internal capsule (4/5), cerebellum (3/5), and periventricular white matter (3/5); in each patient, there was improvement both clinically and on MRI. The causes of PRES in these five patients were hypertension (n=2), cyclosporine (n=2), and eclampsia (n=1). The incidence of the central variant may be increasing because of an improving awareness of the diverse imaging patterns of PRES.

Can clinical and MRI findings predict the prognosis of variant and classical type of posterior reversible encephalopathy syndrome (PRES)?

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is characterized by clinical symptoms that are associated with bilateral and symmetric vasogenic edema in the parietal and occipital lobes. However, this is rarely present with predominant involvement of the brain stem and cerebellum (variant).

PURPOSE

To evaluate which clinical or magnetic resonance imaging (MRI) findings can help to predict the prognosis of variant and classical type of PRES and whether or not there is difference between two types of PRES.

MATERIAL AND METHODS

We retrospectively evaluated MRI and clinical findings from 49 patients with PRES. These patients were divided into two groups. In group I, patients had atypical distribution of lesions. In group II, patients had typical distribution of lesions. Follow-up MRI was performed on 26 patients. We assessed the MRI features, clinical data, and the patients' outcomes.

RESULTS

The mean blood pressure (BP) was significantly higher in group I (195.52/121.09 mmHg and 156.78/99.53 mmHg for groups I and II, respectively). The other factors assessed were not significantly different between the two groups. Lesions in 24 of 26 patients reversed upon follow-up. Sequelae were observed in 11 patients (group I, 7; group II, 4). However, there were no significant differences between the two groups. Except for those patients who died, seven of the nine patients with sequelae upon follow-up imaging had hemorrhage or irreversibility of lesions.

CONCLUSION

Even though BP influences the involvement of the brain stem, involvement of the brain stem is not influential on the prognosis. It seems that the influential factor to prognosis is the reversibility of lesions and hemorrhage.

Hypertensive encephalopathy with reversible brainstem edema

Presented here is a 36-year-old male with arterial hypertension who developed brainstem edema and intracranial hemorrhage. Magnetic resonance scan revealed diffuse brainstem hyperintensity in T2-weighted and fluid-attenuated inversion-recovery images, with an increase in apparent diffusion coefficient values. After a reduction in blood pressure, rapid resolution of the brainstem edema was observed on follow-up. The patient's condition was thus interpreted as hypertensive brainstem encephalopathy. While many consider this a vasogenic phenomenon, induced by sudden, severe hypertension, the precise mechanism remains unclear. Prompt recognition and aggressive antihypertensive treatment in such patients are essential to prevent permanent or life-threatening neurologic injury.

Posterior Reversible Encephalopathy Syndrome and Anti-Angiogenic Agents: A Case Report

Posterior reversible encephalopathy syndrome is an increasingly recognised clinico-radiological entity, associated with several medical conditions (such as systemic arterial hypertension) and characterised by seizures, altered mental status, headaches, and visual symptoms. Magnetic resonance imaging is a key component in this diagnosis, with hyperintense foci in T₂-weighted images, corresponding to vasogenic oedema. The pathophysiology is not fully understood but probably involves loss of auto-regulation of cerebral vasculature or endothelial dysfunction or both. A 56-year-old male, suffering from a gastro-intestinal stromal tumour with hepatic metastasis resistant to imatinib, on therapy with sunitinib, came to the Emergency Department because of headaches, hallucinations, and loss of vision. There was no previous history of high blood pressure. A hypertensive crisis was diagnosed; ophthalmological examination on admission showed no light perception bilaterally. Brain imaging displayed bilateral parieto-occipital and frontal vasogenic oedema, consistent with the clinical diagnosis of posterior reversible encephalopathy syndrome. After treatment of hypertension and suspension of sunitinib, the patient recovered from his symptoms. Control imaging showed no oedema. Angiogenesis inhibitors, such as sunitinib and bevacizumab, can cause hypertension, one of the many medical conditions associated with the posterior reversible encephalopathy syndrome. This syndrome should be considered in cases of acute visual loss, particularly in view of its reversible nature when diagnosed and treated promptly.

Involvement of the cervical cord and medulla in posterior reversible encephalopathy syndrome

The posterior reversible encephalopathy syndrome (PRES) is characterized by patchy cortical and subcortical lesions in the distribution of the posterior circulation. The lesions are classically reversible. This syndrome has multiple etiologies, most of which cause acute hypertension. We present a case of PRES with involvement of the medulla and cervical cord (apart from the typical parieto-occipital lesions)--an extremely rare imaging manifestation of PRES. It is important to recognize the imaging findings of PRES in spinal cord, and avoid misdiagnosis as myelitis by proper clinical correlation. Typically patients with myelitis have a profound neurodeficit, while patients with spinal manifestations of PRES are asymptomatic. Involvement of the cord in PRES has probably been an underrecognized entity as spinal imaging is not routinely performed in posterior reversible encephalopathy syndrome.