Asymmetric Posterior Reversible Encephalopathy Syndrome Complicating Hemodynamic Augmentation for Subarachnoid Hemorrhage-Associated Cerebral Vasospasm

Central Variant Posterior Reversible Encephalopathy Syndrome in a Pregnant Woman With Eclampsia: A Case Report

Posterior Reversible Encephalopathy Syndrome (PRES) is a clinico-radiological diagnosis characterized by acute or subacute neurological symptoms. A 27-year-old woman at 35 weeks of pregnancy, who presented with generalized tonic-clonic seizures had persistently low Glasgow Coma Scale (GCS) score after delivery of the baby. Magnetic Resonance Imaging (MRI) of the brain showed T-2 Fluid Attenuated Inversion Recovery (FLAIR) hyperintensities in the brainstem, bilateral medial cerebellar hemispheres, bilateral medial temporal lobes, bilateral thalami, lentiform and caudate nuclei, and bilateral fronto-parieto-occipital lobes. There was diffusion restriction in bilateral caudate nuclei, left thalamus and right frontal lobe, and microhemorrhages in the left thalamus. These findings were suggestive of central variant PRES. She improved with strict blood pressure control and anti-edema measures. A repeat MRI brain on day 10 showed significant improvement, and she had no residual neurological deficits. The central variant of PRES is a rare entity that has to be considered in a patient presenting with neurological deficits in the setting of uncontrolled blood pressure, eclampsia, immunomodulatory medication use, or renal failure. While most patients with PRES fully recover with timely therapy targeted at reversing the primary cause, some may have residual neurological deficits or rarely, die.

Asymmetric posterior reversible encephalopathy syndrome secondary to epilepsy occurring in the chronic phase of subarachnoid hemorrhage

Background:

Posterior reversible encephalopathy syndrome (PRES) is a rare clinical syndrome that refers to a disorder with reversible subcortical vasogenic brain edema involving the parieto-occipital lobe, temporal lobe, basal ganglia, and its surroundings. Radiologically, it is characterized by symmetrical lesions; however, atypical findings have sometimes been reported.

Case Description:

A 79-year-old woman experienced subarachnoid hemorrhage (SAH) a year and a half previously before this hospitalization. She presented with sudden-onset coma, dacryorrhea, and moderate right hemiparesis and was taken to our hospital. Computed tomography showed no apparent abnormal acute lesions. Electroencephalography confirmed periodic lateralized epileptiform discharges in the left hemisphere. First, based on the findings, she was diagnosed with nonconvulsive status epilepticus and started antiepileptic therapy. Six days after admission, however, multiple asymmetric lesions were confirmed on magnetic resonance imaging. Considering that findings subsequently improved, we finally diagnosed her with asymmetric PRES secondary to epilepsy occurring in the chronic phase of SAH. Aphasia and right hemispatial neglect persisted as sequelae and she was transferred to a rehabilitation hospital with a modified Rankin scale of 3.

Conclusion:

Excessive elevation of blood flow in the hemisphere is inferred to lead to blood–brain barrier collapse and subsequent asymmetric PRES.

Fluid metabolic pathways after subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating cerebrovascular disease with high mortality and morbidity. In recent years, a large number of studies have focused on the mechanism of early brain injury (EBI) and delayed cerebral ischemia (DCI), including vasospasm, neurotoxicity of hematoma and neuroinflammatory storm, after aSAH. Despite considerable efforts, no novel drugs have significantly improved the prognosis of patients in phase III clinical trials, indicating the need to further re-examine the multifactorial pathophysiological process that occurs after aSAH. The complex pathogenesis is reflected by the destruction of the dynamic balance of the energy metabolism in the nervous system after aSAH, which prevents the maintenance of normal neural function. This review focuses on the fluid metabolic pathways of the central nervous system (CNS), starting with ruptured aneurysms, and discusses the dysfunction of blood circulation, cerebrospinal fluid (CSF) circulation and the glymphatic system during disease progression. It also proposes a hypothesis on the metabolic disorder mechanism and potential therapeutic targets for aSAH patients.

Posterior reversible encephalopathy syndrome after induced hypertension therapy for delayed cerebral ischemia after subarachnoid hemorrhage: A case-control study

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is associated with arterial hypertension. Our aim was to investigate whether induced hypertension (IH) as therapy for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is associated with PRES and to identify risk factors for PRES.

MATERIAL AND METHODS

We retrospectively searched our database for patients with SAH and IH in our institution between 2009 and 2018 and identified additional cases of PRES after SAH with IH from the literature. We then analyzed demographic findings and clinical features of these patients.

RESULTS

172 patients with acute SAH received IH. PRES was diagnosed in 3/172 (1.7%) patients. Our literature search revealed 17 additional cases. The pooled PRES group (n = 20) was non-significantly older than the non-PRES group (n = 169) (median, 62.5 years vs. 52 years, p = 0.06). No significant differences were found between both groups with regard to sex (p = 0.73), Hunt & Hess-Score (p = 0.9), aneurysm treatment (p = 0.13), and time from diagnosis of SAH to the start of IH (p = 0.14).

CONCLUSIONS

PRES after IH in SAH patients occurred in 1.7% of our patients. Our results imply that it is important to be aware of a possible development of a PRES in older SAH patients with IH, irrespective of sex, initial clinical status, and treatment modality.

Posterior Reversible Encephalopathy Syndrome Caused by Induced Hypertension to Treat Cerebral Vasospasm Secondary to Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

The aim of the present study was to describe the case of a patient who had presented to a university hospital with induced-hypertension (IH) posterior reversible encephalopathy syndrome (PRES). We also reviewed all other reports of such patients.

METHODS

We have described the clinical course of a patient who had presented to the university hospital neurosurgical department. We also performed a systematic review of studies related to the incidence of PRES caused by the use of IH in the treatment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage.

RESULTS

The patient had presented with an acute-onset headache and found to have a subarachnoid hemorrhage due to anterior communicating artery aneurysm rupture. She underwent coiling the next day. During the subsequent days, she demonstrated fluctuating clinical examination findings, aphasia, and decreased levels of arousal. Digital subtraction angiography was performed, and the findings were concerning for mild vasospasm of the anterior and middle cerebral arteries. The systolic blood pressure goal was increased to 180-220 mm Hg for an IH trial, which had initially resulted in some transient clinical improvements in her level of arousal. However, the improvement was not sustained. During the next 36 hours, the patient worsened, and she developed left middle cerebral artery syndrome. Given the concern for a possible ischemic event, magnetic resonance imaging was performed, which demonstrated interval development of multiple areas of cortical-based fluid-attenuated inversion recovery hyperintensity consistent with PRES. The systolic blood pressure goal was relaxed to normotension, and ~48 hours later, the patient's clinical status had significantly improved.

CONCLUSION

IH-PRES is a rare complication that should be remembered in the differential diagnosis for at-risk patients.

A Case of Posterior Reversible Encephalopathy Syndrome After Surgical Clipping of Unruptured Cerebral Aneurysm

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is characterized by reversible edematous lesions on imaging examinations, along with symptoms of altered consciousness disorder and seizures. Various factors associated with PRES have been reported. However, we encountered a very rare case that developed after clipping surgery for unruptured cerebral aneurysm.

CASE DESCRIPTION

A 74-year-old man with a history of hypertension presented with an unruptured right middle cerebral artery aneurysm and underwent cranial clipping surgery. After surgery, he developed consciousness disorder and epilepsy after delayed awakening from general anesthesia. Radiological examinations revealed multiple edematous lesions, strongly suggesting PRES, and excluding asymmetry consistent with the area of craniotomy. With conservative treatment, symptoms and radiological findings almost disappeared. Symptoms and imaging findings remaining at the area of craniotomy were attributed to the severe difference in cerebral perfusion pressure due to craniotomy.

CONCLUSIONS

Based on the literature, this case was considered to represent PRES caused by rapid blood pressure fluctuations accompanying general anesthesia for clipping surgery. Practitioners must keep PRES in mind as a rare complication after clipping for unruptured cerebral aneurysms. PRES developing after craniotomy shows unilaterality and may become severe in the craniotomy area and leave sequelae.

Protective effect of unilateral vasospasm in the setting of HHH-associated posterior reversible encephalopathy syndrome: case report, review of the literature, and treatment considerations

Background

Hyperdynamic therapy, also called triple-H therapy, is the standard treatment and prophylaxis for aneurysmal-associated vasospasm. In patients who are able to tolerate cardiopulmonary stressors induced by this therapy, it is of benefit as a modality for prevention and treatment of delayed ischemic neurologic deficit. However, it can be a cause of significant cardiopulmonary or neurologic sequelae. In rare cases, it can be associated with posterior reversible encephalopathy syndrome (PRES), secondary to prolonged vasopressor and hypertensive therapies.

Case presentation

We present the case of a patient with right-sided aneurysmal-associated vasospasm who, after 10 days of triple-H therapy, experienced a seizure and was found to have left-sided PRES. Right-sided vasospasm served as a protective mechanism from triple-H therapy-associated PRES. It presented a treatment conundrum due to contradictory perfusion requirements. Hypertensive therapy was curtailed and in efforts to preserve local cerebral perfusion and vasodilation, local therapy with intrathecal nicardipine was initiated. We present our case, a review of the literature, and management considerations.

Conclusions

Therapies that have conventionally functioned as second line treatments for aneurysmal subarachnoid hemorrhage (intra-arterial vasodilators and intrathecal vasodilators) may be beneficial as earlier treatments in the setting of vasospasm given the systemic difficulties and complications associated with HHH therapy in patients with PRES.

Posterior reversible encephalopathy syndrome complicated with subarachnoid hemorrhage in an eclamptic pregnant patient: case report

Background

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic condition which comprises various neurological symptoms. This syndrome could be complicated by intracranial hemorrhage including subarachnoid hemorrhage (SAH). However, SAH is rarely seen in eclamptic patients with PRES.

Case presentation

A 34-weeks-pregnant woman at the age of 33 was admitted to the obstetrics department because of an episode of generalized tonic-clonic seizure. Before the seizure, the patient had a headache and was found to have an abnormal systolic blood pressure of 160 mmHg. On admission, systolic and diastolic blood pressures were up to 182 and 99 mmHg, respectively. Emergent cesarean section was then performed. On hospital day (HD) 2, cranial non-contrast computed tomography (CT) revealed the existence of SAH. Multiple areas of high signals on T2-weighted and fluid attenuated inversion recovery (FLAIR) sequences were shown by cranial magnetic resonance imaging (MRI) performed 2 days later. CT-angiography studies didn’t reveal intracranial aneurysm. After anti-hypertensive treatment, arterial blood pressure of the patient was gradually tapered to normal values. Eventually, the patient was discharged without any residual symptoms.

Conclusions

SAH is a rare complication of PRES in eclamptic patients. In patients with PRES, occurrence of SAH is related to increased morbidity and mortality especially when the hemorrhage is diffuse or massive. Our patient had a minor hemorrhage. The good prognosis might also be due to immediate elimination of the risk factor of PRES by emergent delivery.

Posterior Reversible Encephalopathy Syndrome as a Complication of Induced Hypertension in Subarachnoid Hemorrhage: A Case-Control Study

BACKGROUND

Induced hypertension (IH) remains the mainstay of medical management for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH). However, raising blood pressure above normal levels may be associated with systemic and neurological complications, of which posterior reversible encephalopathy syndrome (PRES) has been increasingly recognized.

OBJECTIVE

To ascertain the frequency and predisposing factors for PRES during IH therapy.

METHODS

We identified 68 patients treated with IH from 345 SAH patients over a 3-yr period. PRES was diagnosed based on clinical suspicion, confirmed by imaging. We extracted additional data on IH, including baseline and highest target mean arterial pressure (MAP), comparing PRES to IH-treated controls.

RESULTS

Five patients were diagnosed with PRES at median 6.6 d (range 1-8 d) from vasopressor initiation. All presented with lethargy, 3 had new focal deficits, and 1 had a seizure. Although baseline MAP (prior to DCI) did not differ between cases and controls, both MAP immediately prior to IH (112 vs 90) and highest MAP targeted were greater (140 vs 120 mm Hg, both P < .01). Magnitude of MAP elevation was greater (54 vs 34 above baseline, P = .004) while degree of IH was not (37 vs 38 above pre-IH MAP). All 4 surviving PRES patients had complete resolution with IH discontinuation.

CONCLUSION

PRES was diagnosed in 7% of SAH patients undergoing IH therapy, most often when MAP was raised well above baseline to levels that exceed traditional autoregulatory thresholds. High suspicion for this reversible disorder appears warranted in the face of unexplained neurological deterioration during aggressive IH.

Rapid intracranial pressure drop as a cause for posterior reversible encephalopathy syndrome: Two case reports

Background:

Posterior reversible encephalopathy syndrome (PRES) is characterized by reversible edematous lesions on radiological examinations as well as symptoms of altered consciousness and seizures. To date, the underlying mechanism remains largely unknown.

Case Descriptions:

Case 1 is a 72-year-old man with a history of hypertension presented with a subarachnoid hemorrhage. Fourteen days after the successful clipping of a ruptured aneurysm; he experienced inadvertent overdrainage via the intraventricular drain. Nine hours later, he started to have seizures followed by disturbances in consciousness. An emergency magnetic resonance imaging showed multiple high-intensity lesions in the frontal, temporal, parietal, and occipital lobes, basal ganglia, brainstem, and cerebellar hemispheres bilaterally, which are compatible with typical magnetic resonance findings in PRES patients. He was treated conservatively and recovered well. Case 2 is a 68-year-old woman with a mild history of hypertension and a ventriculo-peritoneal shunt for obstructive hydrocephalus, who underwent a cysto-peritoneal shunt placement because of an enlarging symptomatic arachnoid cyst. Immediately following surgery, she experienced disturbances in consciousness and developed status epilepticus. Radiological examinations revealed remarkable shrinkage of the arachnoid cyst and multiple edematous lesions, which led us to strongly suspect PRES. With conservative treatment, her symptoms and the radiological abnormalities disappeared.

Conclusion:

Based on the previous literature and our cases, we believe that the association between rapid reduction of intracranial pressure (ICP) and the development of PRES should be recognized because most neurosurgical procedures such as craniotomy or cerebrospinal fluid diversion present a potential risk of rapid reduction of ICP.

Posterior Reversible Encephalopathy Syndrome as an Overlooked Complication of Induced Hypertension for Cerebral Vasospasm

Background and Purpose—

Delayed cerebral ischemia associated with cerebral vasospasm is a common cause of secondary neurological decline after aneurysmal subarachnoid hemorrhage (SAH). Triple-H therapy, induced hypertension, hypervolemia, and hemodilution, is often used to treat cerebral vasospasm. However, hypertensive treatment may carry significant medical morbidity, including cardiopulmonary, renal, and intracranial complications. Posterior reversible encephalopathy syndrome (PRES) is a reversible intracranial complication that has rarely been reported in the setting of induced hypertension.

Methods—

We present an illustrative case of PRES in a patient with induced hypertension for SAH-related cerebral vasospasm and performed a systematic review. Furthermore, the electronic database MEDLINE was searched for additional data in published studies of PRES after induced hypertension.

Results—

Overall, 7 case reports presenting 10 patients who developed PRES secondary to induced hypertension were found. Eighty-two percent of the patients were women. In all cases, the clinical symptoms were attributed to cerebral vasospasm before the diagnosis of PRES. The time from onset of induced hypertension to the development of PRES was 7.8±3.8 days. After the diagnosis of PRES and careful taper down of the blood pressure, the neurological symptoms resolved almost completely within a few days in all patients.

Conclusions—

PRES in the setting of SAH is an overlooked complication of hypertensive therapy for the treatment of vasospasm. However, the diagnosis of this phenomenon is crucial given the necessity to reverse hypertensive therapy, which is contrary to the usual management of patients with vasospasm.

A survey of blood pressure parameters after aneurysmal subarachnoid hemorrhage

Purpose/aim: Blood pressure (BP) regulation is recommended following aneurysmal subarachnoid hemorrhage (aSAH) to prevent re-bleeding and to treat delayed cerebral ischemia. However, optimal BP thresholds are not well established. There is also variation with regard to the BP component (e.g. systolic vs. mean) that is targeted or manipulated.

MATERIALS AND METHODS

An 18-question survey was distributed to physicians and advanced practitioner members of the Neurocritical Care Society. Respondents were asked which BP parameter they manipulated and what their thresholds were in different clinical scenarios. They were also asked whether they were influenced by the presence of incidental aneurysms. Answers were analyzed for differences in training background and treatment setting.

RESULTS

There were 128 responses. The majority were neurointensivists (47 neurology and 37 non-neurology) and treated patients in dedicated neurointensive care units (n = 98). Systolic BP (SBP) was preferred over mean arterial pressure (MAP). Prior to aneurysm treatment, SBP limits ranged from 140 to 180 mm Hg. After aneurysm treatment, SBP limits ranged from 160 to 240 mm Hg. The maximum and minimum MAPs varied by as much as 50%. Nearly two-thirds of the respondents were influenced by the presence of incidental aneurysms. Training background influenced tolerance to BP limits with neurology-trained neurointensivists accepting higher BP limits when treating delayed ischemia ( p = .018). They were also more likely to follow SBP ( p = .018) and have a limit of 140 mm Hg prior to aneurysm treatment ( p = .001).

CONCLUSIONS

There is large practice variability in BP management following aSAH. There is also uncertainty over the importance of incidental aneurysms. Further research could evaluate whether this variability has clinical significance.

Atypical Unilateral Posterior Reversible Encephalopathy Syndrome Mimicking a Middle Cerebral Artery Infarction

Posterior reversible encephalopathy syndrome (PRES) is usually a reversible clinical and radiological entity associated with typical features on brain MR or CT imaging. However, the not-so-uncommon atypical radiological presentations of the condition are also present and they may go unrecognised as they are confused with other conditions. Here, we report a very rare case of atypical, unilateral PRES in a 49-year-old uremic, post-transplant female patient who presented with seizures. Initial MRI showed high-grade occlusion of the left middle cerebral artery (MCA) and lesions suggestive of subacute infarction in the ipsilateral frontotemporoparietal lobe. Patient symptoms had resolved a day after the onset without any specific treatment but early follow-up CT findings suggested hemorrhagic transformation. Follow-up MRI performed 2 years later showed complete disappearence of the lesions and persisting MCA occlusion.

Unilateral reversible posterior leukoencephalopathy syndrome after coiling of an aneurysm

Background

Reversible posterior leukoencephalopathy syndrome (RPLS) is radiologically characterized by symmetrical subcortical areas of vasogenic edema that are preferentially parieto-occipital, and it typically resolves after appropriate treatment.

Case Report

We present a patient with strikingly unilateral RPLS that developed 21 days after coiling of an anterior communicating artery aneurysm and several days of triple-H therapy. Cortical and subcortical vasogenic edema and enhancement developed only in the left hemisphere, with a pattern suggesting RPLS. After 7 months the lesions had nearly completely resolved.

Conclusions

The pathophysiological mechanism underlying RPLS is still not well understood, which makes it difficult to explain the unilateral appearance in this case. Since the imaging findings may be confused with other conditions such as ischemia, recognition of RPLS after coiling is necessary in order to avoid inadequate treatment.

Contrast-induced encephalopathy after coil embolization of an unruptured internal carotid artery aneurysm

A 58-year-old woman developed agraphia and mild right hemiparesis approximately one month after undergoing coil embolization of an unruptured left internal carotid artery aneurysm. MRI performed on day 39 post-coil embolization showed multiple lesions in the white matter with signal hyperintensity on T2-weighted and FLAIR images in the left middle cerebral artery territory. The patient's cerebrospinal fluid exhibited an elevated protein level at 46 mg/dL; however, no other findings suggested another underlying disease. Corticosteroids were administered, and, by day 50 post-coil embolization, the clinical findings and abnormal features on MRI had improved. The patient was therefore diagnosed with contrast-induced encephalopathy after coil embolization.

Hyperperfusion syndrome after stent/coiling of a ruptured carotid bifurcation aneurysm

The authors report a syndrome of regional, symptomatic cerebral hyperperfusion, and edema mimicking infarction in a 54-year-old woman following coiling of a ruptured right carotid bifurcation aneurysm and stenting of the right middle cerebral artery. The patient presented with a Hunt and Hess grade III subarachnoid hemorrhage 7 days after developing thunderclap headache. She underwent successful coiling under general anesthesia of the 1.6 × 1.5 × 1.6 cm aneurysm, but immediately after the coil was placed occlusion of the proximal M1 segment was developed. This occlusion was stented after ~5-min delay, and flow restored without angiographic evidence of distal emboli. Following the procedure, she was extubated and noted to have left hemiparesis, neglect, and mutism without a CT correlate. Cerebral infarction was suspected, but urgent repeat angiography demonstrated patent cerebral vasculature. On the following day, symptoms persisted, and non-contrast head CT now showed cerebral edema localized to the right middle cerebral artery territory mimicking subacute infarction. CT perfusion imaging and angiography showed a widely patent MCA circulation, and suggested a regional hyperperfusion syndrome. The blood pressure was incrementally lowered, with rapid and sustained neurological improvement. Hyperperfusion events following aneurysm repair and related circumstances are reviewed.

[A case of posterior reversible encephalopathy syndrome associated with coil embolization of a basilar apex aneurysm]

About three weeks after successful coil embolization of a basilar apex aneurysm, a 66-year-old woman developed occipital headaches. T2 and FLAIR MRI brain images demonstrated multiple new hyperintense lesions in the posterior circulation territory including cerebellum, right superior cerebellar peduncle, left thalamus and bilateral temporo-occipital lobes and she was subsequently hospitalized. Findings suggestive of other underlying disease were not observed, although an increased protein level was noted in cerebrospinal fluid (69 mg/dl). Headache and clinical findings improved approximately 12 weeks after coil embolization. MRI findings also showed improvement. These clinical and radiological findings made this patient a distinctive case of posterior reversible encephalopathy syndrome (PRES) associated with coil embolization suggesting that clinicians should be aware that PRES can present as comparatively mild symptoms several weeks after coil embolization.