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

Abstract

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.

Shunt Overdrainage: Reappraisal of the Syndrome and Proposal for an Integrative Model

“…Overdrainage of CSF may appear in an acute manner. Postoperative extradural hematoma [42] and the development of posterior reversible encephalopathy [43] have been described, caused by intraoperative overdrainage of CSF with rapid reduction in ICP as a result of a craniotomy or CSF diversion procedure. Regarding chronic overdrainage, we should always consider a silent period of asymptomatic (radiological) overdrainage of variable duration.…”

Posterior Reversible Encephalopathy Syndrome After Epilepsy Surgery Alerted by Low-Processed Electroencephalography Levels: A Case Report

“…Brain surgery has been shown to initiate a neuroinflammatory response. 6 Niwa et al 7 proposed that a sudden drop in intracranial pressure may lead to mechanical stress on the blood vessels, causing mechanical vasoconstriction and edema. We found another case that described PRES as having developed after a transnasal endoscopic resection of a pituitary tumor.…”

Chronic Pediatric Headache as a Manifestation of Shunt Over-Drainage and Slit Ventricle Syndrome in patients harboring a Cerebrospinal Fluid Diversion System: A Systematic Literature Review

“…Overdrainage of CSF may appear in an acute manner, but this complication is not intimately related with the development of chronic refractory headaches [36,37]. Whenever chronic overdrainage is been evaluated and suspected, we should always take into consideration the possibility that a silent period of asymptomatic overdrainage of variable, and unknown, duration pre-exists.…”

“…These variations in the measurements of ICP could be used as a guidance when we attempt to increase the reservoir height. There are reports that have proposed that the spontaneous ICP fluctuations, along with the ICP variations to progressive changes of reservoir height could be considered as the basis for planning of the ongoing treatment options [37]. Several relevant studies [72][73][74][75] have adopted a treatment protocol which is based upon the ICP values.…”