The primary problem is chronically elevated intracranial pressure icp, and the most important neurologic manifestation is papilledema see the image below, which may lead to secondary progressive optic atrophy. Jan 02, 2019 idiopathic intracranial hypertension iih is a disorder of unknown etiology that predominantly affects obese women of childbearing age. Spaceflightinduced intracranial hypertension and visual. Commentary by kathleen digre, md, and judith warner, md idiopathic intracranial hypertension.
Cerebral ischemia is the result of decreased brain perfusion secondary to increased icp. Rises in intracranial pressure icp can occur after any brain injury, mild to severe maintaining adequate cerebral perfusion is the goal serial neurological assessments with documentation of the neurological trending can detect the rising icp transfer may be necessary for higher level of care and neurosurgical interventions 35. They found that elevated csf but not serum retinol concentration was associated with iih. There are multiple causes of iht and bh, and a pathophysiological. The intracranial hypertension syndrome corresponds to the stage at which the increased intracranial pressure can be compensated and the acute form of intracranial hypertension is equivalent to a. Idiopathic intracranial hypertension iih is a disease of unknown etiology typically affecting young, obese women, producing a syndrome of increased intracranial pressure without identifiable cause. Idiopathic intracranial hypertension iih is a disorder of unknown aetiology, primarily affecting women of childbearing age with raised body mass index bmi, characterised by signs and symptoms of raised intracranial pressure icp. Ce is a leading cause of inhospital mortality, occurring in 60% of patients with mass lesions, and.
Causes of secondary ih idiopathic intracranial hypertension. Other findings on funduscopic examination may include macular exudates and macular edema, choroidal folds across the macula usually resulting from flattening of the globes from increased intracranial pressure. Review update on the pathophysiology and management of. Prognosis and treatment, section on treatment goals and monitoring. Idiopathic intracranial hypertension iih is a disorder related to high pressure in the brain. Exploring the current management idiopathic intracranial. Intracranial pressure icp critical care services ontario. Dec 12, 2019 idiopathic intracranial hypertension iih, previously referred to as pseudotumor cerebri, is a disorder of increased intracranial pressure. How i manage intracranial hypertension critical care full text. Incidence is 1100,000 in normalweight women but 20100,000 in obese women. The natural course of this condition inevitably leads to brain death. Modern revisions in the terminology and diagnostic criteria for iih help guide clinicians in investigations and researchers in standardising recruitment criteria for clinical trials. Traumatic brain injury tbi is the most common cause of intracranial hypertension 1.
The primary problem is chronically elevated intracranial pressure icp, and the most important neurologic manifestation is papilledema see the image below, which may lead to secondary progressive optic atrophy, visual loss, and possible blindness. Increased systemic vascular resistance, increased vascular stiffness, and increased vascular responsiveness to stimuli are central to the pathophysiology of hypertension. Management of increased intracranial pressure stephan a. Review of english language scientific and clinical literature using brs colleague search. Idiopathic intracranial hypertension iih is a disorder of unknown etiology that predominantly affects obese women of childbearing age. Pseudotumor cerebri, more commonly referred to as idiopathic intracranial hypertension iih, is characterized by increased intracranial pressure icp with no explanatory findings on imaging studies or in cerebrospinal fluid csf analysis, and may be accompanied by symptoms of chronic headache, tinnitus, papilledema and progressive vision. Benign intracranial hypertension etiology, clinical and therapeutic aspects alexandra tzoukeva, nadezhda deleva, ara kaprelyan, ivan dimitrov ist clinic of neurology, department of neurology, prof. The most common symptoms of intracranial hypertension are headaches and. In the latter process, increased cbf and cbv due to vessel dilation with bbb disruption may lead to aggravated vascular engorgement and brain edema.
Acute hypertension in intracerebral hemorrhage pathophysiology and management. Find out who is at risk for iih, how it is diagnosed and. Diagnosis and management of benign intracranial hypertension. Review evolving evidence in adult idiopathic intracranial.
Intensive care management and the treatment of refractory increases in icp are also outlined. An elevation in intracranial pressure can be a medical or surgical. Tbi has an annual incidence of about 200 cases per 100,000 population 2. The diverse etiologic factors associated with bih include lateral or superior longitudinal sinus thrombosis, menstrual irregularities with obesity, a heterogenous. Identify the components of intracranial pressure icp. The pathophysiology and causes of raised intracranial. Pathophysiology of raised intracranial pressure springerlink. By definition, the term iih describes patients with isolated raised icp that is not related to an intracranial disorder, a meningeal process, or cerebral venous thrombosis. Idiopathic intracranial hypertension pseudotumor cerebri. Idiopathic intracranial hypertension typically occurs in women of childbearing age.
Intracranial hemorrhage ie, the pathological accumulation of blood within the cranial vault may occur within brain parenchyma or the surrounding meningeal spaces. Idiopathic intracranial hypertension iih is a syndrome of increased intracranial pressure without evident cause. The pathophysiology of hypertension is an area which attempts to explain mechanistically the causes of hypertension, which is a chronic disease characterized by elevation of blood pressure. Stoyanov medical university of varna journal of imab annual proceeding scientific papers 2007, vol.
As for many other treatment options in intensive care, a single threshold is debatable. There is an expected rise in prevalence in line with the escalating global burden of obesity. Idiopathic intracranial hypertension iih is a disease defined by elevated intracranial pressure without established etiology. The harmful effects of intracranial hypertension are primarily due to brain injury caused by cerebral ischemia. Hemorrhage within the meninges or the associated potential spaces, including epidural hematoma, subdural hematoma, and subarachnoid hemorrhage, is covered in detail in other. More sih causes are thought to exist, but research is needed to confirm whether there are true relationships. Pathophysiology and management of intracranial hypertension and. Idiopathic intracranial hypertension iih is a syndrome characterized by increased intracranial pressure icp of unknown cause table 1. Many brain processes that cause death are mediated by intracranial hypertension ich. Pathophysiology and countermeasures lifan zhang and alan r. Idiopathic intracranial hypertension iih, previously referred to as pseudotumor cerebri, is a disorder of increased intracranial pressure.
Intracranial hypertension after traumatic brain injury. Clinical features include headaches, pulsesynchronous tinnitus, transient visual obscurations, visual loss, neck and back pain, and diplopia. Pathophysiology and treatment of cerebral edema in traumatic. Sep 25, 2017 idiopathic intracranial hypertension iih. Update on the pathophysiology and management of idiopathic. Pdf pathophysiology of severe traumatic brain injury and. The exact pathogenesis of iih remains elusive but it is also plausible that the syndrome represents the common final pathway of several. Modern revisions in the terminology and diagnostic criteria for iih help guide clinicians in investigations and researchers in.
If hyperemia combines with bbb disruption, capillary leakage in the dilated vascular bed may cause a brain edema to occur 32. Increased intracranial pressure statpearls ncbi bookshelf. The purpose of the article is to provide the anesthetist with a working. Pathophysiology of severe traumatic brain injury and management of intracranial hypertension. The pathophysiology and causes of raised intracranial pressure. Hargens department of aerospace physiology, fourth military medical university, xian, china.
Intracranial pressure intracranial hypertension acute brain injury cerebral perfusion. The pressure in the cranial vault is measured in millimeters of mercury mm hg and is normally less than 20 mm hg. Pdf on dec 9, 2016, jinheon jeong and others published the pathophysiology of brain edema and intracranial hypertension find, read and cite all the research you need on researchgate. Although there is now consensus on the definition of the disorder, its complex pathophysiology remains elusive. Cerebral edema ce and resultant intracranial hypertension are associated with unfavorable prognosis in traumatic brain injury tbi. Chronic intracranial hypertension can be caused by many conditions including certain drugs such as tetracycline, a blood clot in the brain, excessive intake of vitamin a, or brain tumor. In chronic intracranial hypertension, the increased csf pressure can cause swelling and damage to the optic nervea condition called papilledema. The most common clinical symptoms of iih include headache and visual complaints. Iih primarily affects women of childbearing age who are overweight. Jul 05, 2019 intracranial hypertension is a condition due to high pressure within the spaces that surround the brain and spinal cord. Physiology, pathophysiology and management barbara shwiry, crna joseph p. Intracranial hypertension, is a neurological disorder characterized by increased intracranial pressure resulting in temporary or permanent loss of vision. The most popular hypothesis is that idiopathic intracranial hypertension iih is a syndrome of reduced cerebrospinal fluid absorption. This disorder presents more commonly in obese, young women, presenting commonly as headaches and papilledema.
I diopathic intracranial hypertension iih, formerly known as pseudotumor cerebri, is a disorder characterized by elevated intracranial pressure icp and remains a diagnosis of exclusion. Idiopathic intracranial hypertension etiology bmj best. Normal intracranial pressure icp reflects the integration of pressures from the cerebral veins and cerebrospinal fluid. Idiopathic intracranial hypertension in a 24yearold woman. Intracranial hypertension statpearls ncbi bookshelf. It has been a longstanding challenge to clinicians and investigators to explain the pathophysiology of the diverse syndromes collectively termed benign intracranial pressure bih, or pseudotumor cerebri. Intracranial hypertension causes, risk factors, symptoms.
It is also sometimes called pseudotumor cerebri or benign intracranial hypertension. Emergency management of increased intracranial pressure. Pathophysiology is a branch of medicine which explains the function of the body as it relates to diseases and conditions. These spaces are filled with cerebrospinal fluid csf, which cushions the brain from mechanical injury, provides nourishment, and carries away waste. Vitamin a levels in idiopathic intracranial hypertension. Hypertension can be classified by cause as either essential also. Idiopathic intracranial hypertension iih is a rare but important disease associated with signi. Pathophysiology and treatment of cerebral edema in. Hypertension is a cause of morbidity and mortality. Brain injury, cerebral perfusion, decompressive craniectomy, head injury, intracranial pressure.
The diverse etiologic factors associated with bih include lateral or superior longitudinal. Basic concepts about brain pathophysiology and intracranial. The most common symptoms are headaches and vision loss. Idiopathic intracranial hypertension iih is a rare but important disease associated with significant morbidity. Intracranial hypertension ih is a clinical condition that is associated with an elevation of the pressures within the cranium. Injury severe enough to warrant icp therapy, known as severe tbi, occurs in only 10% of cases. In fact, recent evidence suggests that not a single value but. However, patients who develop a syndrome of raised icp secondary to. Update on the pathophysiology and management of idiopathic intracranial hypertension vale.
Idiopathic intracranial hypertension national eye institute. Pdf the pathophysiology of brain edema and intracranial. It discusses the nursing care, treatment and management required in order to minimize the risk of further increases in icp. Currently, microgravityinduced headward blood and fluid shifts are considered the primary etiological factors causing chronic and mildly elevated intracranial hypertension as compared with variable icps on earth 8, 85, 157, 163, 182, 192, 204, 217, but the exact degree of intracranial fluid shift and the relevant mechanisms remain. Benign intracranial hypertension bih is a headache syndrome characterised by 1 raised cerebrospinal fluid csf pressure in the absence of an intracranial mass lesion or ventricular dilatation. The pathophysiology of the intracranial hypertension in pseudotumor cerebri is still an unsolved puzzle. Pathophysiology of severe traumatic brain injury and. The fluid that surrounds the spinal cord and brain is called cerebrospinal fluid or csf. Idiopathic intracranial hypertension iih is caused by high pressure in the spaces that surround the brain and spinal cord.
Pdf idiopathic intracranial hypertension iih is a disease defined by elevated intracranial pressure without established etiology. Despite a large number of hypotheses and publications over the past decade, the etiology is still unknown. Understanding the complex pathophysiology of idiopathic. Idiopathic intracranial hypertension iih predominantly occurs in young obese women,14 but about 9% of cases occur in men. Increased resistance to csf outflow leading to an increased csf volume interstitial brain edema johnston and paterson 1975, gjerris et al. The deleterious effects of raised intracranial pres sure are a. Evolving evidence in adult idiopathic intracranial. Several men in his expedition developed secondary intracranial hypertension sih and nearly died after consuming polar bear liver. Anytime there is an elevation in icp, there is the risk of subsequent injury from direct brainstem.